Showing papers by "University of Leicester published in 1986"
TL;DR: The Kohistan Arc as discussed by the authors is essentially a crustal 'pop-up' with southward-upright and northward-verging structures developed above a thick ductile decoupling zone (the Indus Suture), which can be traced for >100 km beneath Kohistan on large reentrants.
Abstract: West Himalayan tectonics involve the Collision of microplates between the Indian and Asian Plates. The Kohistan Complex consists largely of tightly folded basic volcanics and sediments generated as Late Jurassic to Late Cretaceous island arcs. These were intruded by post-folding Mid-Cretaceous Eocene plutonics produced from continued subduction of the Indian Plate after closure of a suture between Kohistan and the Karakorum. The Himalayan structures show major thrust sheets and the Kohistan Arc is essentially a crustal 'pop-up' with southward-upright and northward-verging structures developed above a thick ductile decoupling zone (the Indus Suture), which can be traced for >100 km beneath Kohistan on large reentrants. This pop-up formed by a two stage process, closure of the Northern Suture followed by closure of the southern Indus Suture. Granitic rocks of the Kohis tan-Ladakh Batholith (dated at = 100-40 Ma) post-date most of the structures related to the Northern Suture but were deformed and carried southwards on shear structures related to the Indus Suture. Postcollisional deformation carried this Kohistan Complex on deep decoupling zones over the Indian Plate on a series of imbricated gneiss sheets, the thrusts climbing up section in the movement direction so that in the far S some override their own molasse debris. Folds above these deep decoupling zones deformed their overlying thrust sheets into large antiforms--i.e. the Nanga Parbat and Hazara Syntaxes. The Nanga Parbat Syntaxis probably formed due to a shear couple near a branch line where one of the main Himalayan thrusts joined the Indus Suture beneath Kohistan. Crustal delamination, to produce the imbricated gneiss sheets, could not account for all the displacement of India into Asia, suggested by palaeomagnetic data. There must also have been lateral displacement as demonstrated by the large oblique-slip shear zone in the Hunza Valley, N of Kohistan.
281 citations
01 Sep 1986
TL;DR: Combined Pb-Sr-Nd isotope and trace element data are presented for eight islands within the Cook-Austral-Samoa island archipelago, southwest Pacific as mentioned in this paper.
Abstract: Combined Pb-Sr-Nd isotope and trace element data are presented for eight islands within the Cook-Austral-Samoa island archipelago, southwest Pacific. These data reveal the presence of two geochemically distinct components within the OIB mantle. The Mangaia component represented by the islands of Mangaia and Tubuai has extremely radiogenic Pb isotopes but low87Sr/86Sr . A Dupal component represented by Samoa has high87Sr/86Sr , with low Pb ratios which are enriched in207Pb and208Pb. Nd isotope ratios of the Dupal component are slightly lower than for Mangaia. The Dupal isotope enrichment is coupled with high LIL/HFS element ratios relative to Mangaia. The Mangaia isotope enrichment is associated with low LIL/HFS element ratios comparable with or lower than MORB and indicates a time-integrated depletion in LIL elements in the source. However, inferred low ThU , and PbNb ratios indicate that Mangaia has been enriched in U but depleted in Pb relative to MORB. It is suggested that Mangaia could be derived from hydrothermally altered, subducted MORB. The Dupal component may include recycled subcontinental lithosphere.
260 citations
TL;DR: 43 term infants with clinical neurological manifestations of intrapartum asphyxia and who survived for more than 2 days were studied sequentially, while in hospital, with doppler ultrasound examination of the anterior cerebral arteries with accuracy and sensitivity, and the prediction of adverse outcome by abnormalDoppler showed a sensitivity and specificity.
181 citations
TL;DR: P-element-mediated transformations involving DNA fragments from the period (per) clock gene of Drosophila melanogaster have shown that several subsegments of the locus restore rhythmicity to per0 or per- mutants.
Abstract: P-element-mediated transformations involving DNA fragments from the period (per) clock gene of Drosophila melanogaster have shown that several subsegments of the locus restore rhythmicity to per0 or per- mutants. Such fragments overlap in a genomic region complementary to one transcript, a 4.5-kb RNA which is probably the per message, in that it is necessary and (in terms of expression from this X-chromosomal locus) sufficient for the fly's circadian rhythms. It is also at least necessary for the high-frequency oscillations normally produced by courting males as they vibrate their wings. The entirety of the 4.5-kb transcript is not necessary for rather strong rhythmicity; nor does it seem to be sufficient, in transformants, for wild-type behavioral phenotypes. A 0.9-kb RNA, homologous to genomic region immediately adjacent to the source of the 4.5-kb species, oscillates in its abundance over the course of a day; but coverage of this transcript source in several transformants carrying a per0 mutation--which eliminates the 0.9-kb RNA's oscillation--does not restore rhythmicity. All of the independently isolated arrhythmic mutations tested were covered by the same array of overlapping per+-derived DNA fragments, implying that the only portion of the locus which has mutated to arrhythmicity is complementary to the 4.5-kb transcript.
172 citations
TL;DR: The trace element and Pb isotopic geochemistry of these lavas is explicable by contamination of the oceanisland basalt source that gave rise to Ascension, Bouvet, St. Helena, Gough and Tristan da Cunha as discussed by the authors.
Abstract: The South Atlantic Ocean islands of Ascension, Bouvet, St. Helena, Gough, and Tristan da Cunha display considerable inter-island (and to a variable extent intra-island) heterogeneity in ratios of highly incompatible trace elements. Basaltic and hawaiitic lavas from Ascension, Bouvet, and St. Helena have consistent trace-lenient ratios (e.g., La/Nb, Ba/Nb, Ba/La, Ba/Th, Rb/Th). In contrast, Tristan da Cunha and Gough (and Walvis Ridge) lavas are depleted in Nb and enriched in Ba relative to other highly incompatible trace elements as compared to the other islands. The trace-element and Pb isotopic geochemistry of these lavas is explicable by contamination of the ocean-island basalt source that gave rise to Ascension, Bouvet, and St. Helena lavas by variable, but small (about 1%), amounts of ancient (1.5–2.0 Ga) pelagic sediment.
165 citations
TL;DR: In this paper, it was shown that the response of trees to the climatic warming at the most recent glacial termination can be explained by the postulated spatial differentiation of raw skeletal soils.
Abstract: In areas such as parts of Britain where many closely spaced sites have been investigated, between-site diversites prevent any simple correlation between vegetation response and climatic variables. These diversities reveal the influence of other factors in modulating this response. Analysis of profiles of allochthonous lake sediments has provided evidence for the importance of soil factors. The otherwise inexplicable spatial variation in the response of trees, in Britain and neighbouring parts of the European mainland, to the climatic warming (inferred from faunal evidence) at the most recent glacial termination, can be explained by the postulated spatial differentiation of raw skeletal soils. Differences in particle-size, composition and drainage, consistent with the spatial differentiation of pre-arboreal vegetation, would affect the water-retaining capacity of immature late-glacial soils and hence the reproductive success of tree birches. The lag in response of these to climatic amelioration appears to have varied from 500 to 1500 yr, and it seems likely that a similar lag may have characterised the early warming period of each interglacial. The coclusion must be that in this situation the degree of success of trees measured by pollen values is not a reliable indicator of palaeotem-peratures. Secondly, it appears from evidence in northern Scotland that at an ecotone between forest types, the relation between vegetation and climate is likely to be obscured except in regions of uniform soils. In areas of differentiated bedrock, the vegetation pattern is likely to have been influenced most by the effects of soil maturation processes in developing a soil mosaic.
156 citations
01 May 1986
TL;DR: In this paper, a self-consistent non-linear theory of radar auroral backscatter is presented, where wave heating is treated as an electron-plasmon collision process.
Abstract: A new self-consistent non-linear theory of radar auroral backscatter is presented. An important feature of this theory is a novel treatment of wave heating as an electron-plasmon collision process. With this formalism electron-plasmon collisions arise in an entirely self-consistent manner in both the perturbation equations and in the electron energy balance equation. The new theory allows the phase speeds of waves which give rise to radar auroral backscatter to be calculated as a function of electron drift speed. The results of the theory are in good quantitative agreement with experimental observations and provide firm theoretical support for recently developed coherent backscatter radar data reduction techniques.
150 citations
TL;DR: The AROM locus of A. nidulans, which governs five consecutive steps in pre-chorismate aromatic amino acid biosynthesis, has been cloned in a bacteriophage vector and reveals a single, open reading-frame of 4,812 base-pairs, apparently without introns.
Abstract: The AROM locus of A. nidulans, which governs five consecutive steps in pre-chorismate aromatic amino acid biosynthesis, has been cloned in a bacteriophage vector. The nucleotide sequence of the locus reveals a single, open reading-frame of 4,812 base-pairs, apparently without introns. An internal segment of the A. nidulans AROM sequence has extensive homology with the E. coli aroA gene that encodes the 5-enolpyruvylshikimate 3-phosphate synthase.
147 citations
TL;DR: In this article, Epictetus states that "the good on its appearance instantly attracts to itself, the bad repels" and "the soul will never reject the worth of something with the manifest appearance of goodness, no more than one would reject Caesar's coin".
Abstract: Epictetus speaks: Just as it is not open to the banker or the greengrocer to reject the value of Caesar's coin, but he is obliged, whether he likes it or not, when you offer it, to hand it over for what he has for sale in exchange for it, so it is with the soul. The good on its appearance instantly attracts to itself, the bad repels. The soul will never reject the worth of something with the manifest appearance of goodness, no more than one would reject Caesar's coin.
140 citations
TL;DR: The E. coli envelope, whose structure has been extensively reviewed, is shown and it is difficult to estimate the precise volume of the periplasmic space under normal growth conditions since it is not structurally defined.
Abstract: Escherichia coli secretes very few proteins into the culture medium and it is presumed that the outer membrane constitutes the major barrier to true secretion. The E. coli envelope, whose structure has been extensively reviewed (Nikaido and Nakae 1979; Osborn and Wu 1980; Hall and Silhavy 1981; Lugtenberg and Van Alphen 1983), is shown in Fig. 1. It is composed of an inner and outer membrane which encloses the peptidoglycan or rigid cell wall. The periplasmic space is also located between the membrane layers. This compartment may contain at least 4% of total cell protein (Nossal and Heppel 1966) and may have a quite viscous or gel-like structure (Hobot et al. 1984). The periplasm contains up to 50 distinct polypeptide species (Copeland et al. 1982), the majority of which are concerned with import mechanisms connecting outer membrane pores (porins) with specific inner membrane permeases. It is difficult to estimate the precise volume of the periplasmic space under normal growth conditions since it is not structurally defined.
136 citations
TL;DR: It is shown that the archetypal consensus sequence is used efficiently, and the cryptic sites of β-globin are characterized: sequences alone can explain why these sites are not normally used.
Abstract: Alternative splicing of eukaryotic messenger RNA precursors is now known to be of widespread importance in generating multiple transcripts from a single gene. This phenomenon has emphasized the problem of the way in which splice sites are selected; recent studies have discussed the role of secondary structure or affinity and spatial relationships in this selection. Splice site sequences vary widely, although a loose consensus has been derived for the 9 bases around the 5' splice site and for a longer region around the 3' splice site. Mutagenesis experiments have defined the sequences essential for a potential 5' splice site, but, except for some experiments with the E1a gene of adenovirus, these experiments have not examined 5' splice site sequences for features responsible for site preference where alternative splicing sites exist. Such tests require a choice of site: an appropriate reference site and a constant position at which test sites are introduced. We have begun a series of experiments designed to show whether splice site sequences can be ranked in a hierarchy of preferential use. Here we show that the archetypal consensus sequence is used efficiently, and characterize the cryptic sites of beta-globin: sequences alone can explain why these sites are not normally used. We also show with the E1a gene of adenovirus, a simple example of alternative splicing, that one of the two 5' splice sites used by this gene is intrinsically stronger. We also demonstrate that tandem repeats and secondary structure influence the choice of sites in vivo. We discuss the mechanism of splice site selection.
TL;DR: It is suggested that magnesium administration reduces the incidence of serious tachyarrhythmias and death after acute myocardial infarction and that this simple regime warrants further study.
TL;DR: In this article, the authors focus on the pattern of fighting between rival groups that has come to be regularly associated with soccer, not only in this country but in a number of others besides.
Abstract: The subject of this paper is 'football hooliganism'. We shall focus centrally in this connection on the pattern of fighting between rival groups that has come to be regularly associated with soccer, not only in this country but in a number of others besides. In fact, although this rarely surfaces in the press, there is scarcely a country where Association football is played where eruptions of crowd violence have not occurred, though English fans are currently the most feared in Europe and the only ones who regularly cause trouble when they are travelling abroad in support of their clubs or the national side.l The research on which the paper is based was funded by the Social Science Research Council (now the ESRC) and the Football Trust. Before we set forth some of our results, we shall sketch in some of the main parameters of football hooliganism as a social phenomenon.
TL;DR: In this article, eight new K-Ar determinations are presented which, together with field relations and previous studies, are used to construct a chronology of the volcanic build-up of Fuerteventura.
Abstract: Eight new K-Ar determinations are presented which, together with field relations and previous studies, are used to construct a chronology of the volcanic build-up of Fuerteventura. The earliest island-building volcanics are late Cretaceous to early Tertiary alkaline basaltic volcaniclastic sediments, and these may be correlated with the early gabbro/pyroxenite intrusions which were probably subvolcanic to the early edifice. This was followed by a carbonatitic subvolcanic complex then by two later high-level gabbro/pyroxenite plutons, the latter being early Miocene or older. The emplacement of a subsequent middle Miocene gabbro/syenite ring complex caused widespread resetting of the Ar contents of the earlier rocks, but nevertheless consideration of the mineralogy of the rocks in conjunction with the field relations enables the long volcanic history ( c . 80 Ma) to be reconstructed.
TL;DR: It was shown that removal of 27 amino acids from the C-terminus of HlyA is sufficient to inhibit secretion drastically, although the residual polypeptide is still haemolytically active, and this results are consistent with a mechanism in which interaction of theC-termini with the secretion machinery, located in the inner membrane, is followed by direct transfer of ha Hemolysin to the medium.
Abstract: As a first step in the detailed analysis of the mechanism of secretion of haemolysin, we sought to identify sequences or domains within haemolysin A (HlyA) that are essential for its secretion. For this purpose we examined the properties of a deletion and Tn5 insertions into the region of theHlyA gene encoding the C-terminal part of the protein, since both of these are relatively simple to generate. We showed that removal of 27 amino acids from the C-terminus of HlyA is sufficient to inhibit secretion drastically, although the residual polypeptide is still haemolytically active. Cellular fractionation studies showed that haemolytic activity does not accumulate in large amounts within the periplasmic space during normal secretion. More significantly, activity does not appear to accumulate within this compartment when the export functionshlyB andhlyD are removed. These results are consistent with a mechanism in which interaction of the C-terminus of HlyA with the secretion machinery, located in the inner membrane, is followed by direct transfer of haemolysin to the medium.
TL;DR: In this paper, a relation periode-luminosite K (2,2 μm) was observed between two amas etudies in the form of P ∞−0,45 M K.
Abstract: Etude de l'utilisation eventuelle de la photometrie dans l'IR proche pour evaluer les distances des amas globulaires On a observe une relation periode-luminosite K (2,2 μm) dans les trois amas etudies; elle est de la forme P ∞−0,45 M K
25 Mar 1986
TL;DR: Despite the fact that the alpha 1(III) collagen gene is located on a chromosome different from thealpha 1(I) and alpha 2 (I) genes, the expression of these three collagen chains appears to be coordinately controlled during periods of rapid and slow fibroblast growth.
Abstract: Type III collagen is one of the major interstitial collagens and, as such, plays an important role in modulating the structure and function of most tissues. To compare the expression of the type III collagen gene to that of the type I collagen alpha 1(I) and alpha 2(I) genes, cDNAs encoding the 3' one-third of the human alpha 1(III) collagen mRNA were obtained by screening a human fetal lung fibroblast cDNA library with a cloned segment of the chicken alpha 1(III) gene. Northern blot analysis of human fetal lung fibroblast RNA demonstrated two alpha 1(III)-specific mRNAs of sizes 6.6 and 5.8 kilobases, sizes clearly different from those of the type I collagen mRNAs. Analyses of populations of dividing and nondividing human lung fibroblasts revealed that, on a per cell basis, the nondividing population contained twice as much alpha 1(III) mRNA than did the dividing population. The same was true for the type I collagen alpha 1(I) and alpha 2(I) mRNA transcripts. Similar results were obtained when alpha 1(III), alpha 1(I), and alpha 2(I) mRNA transcripts were quantified by using dot blot evaluation of total RNA, Northern analysis of total RNA, and dot blot evaluation of cytoplasmic RNA. Thus, despite the fact that the alpha 1(III) collagen gene is located on a chromosome different from the alpha 1(I) and alpha 2(I) genes, the expression of these three collagen chains appears to be coordinately controlled during periods of rapid and slow fibroblast growth.
TL;DR: In this paper, molecular radical models for various muonium-related paramagnetic centres observed in the elemental and compound semiconductors, and for those which are currently being reported in other crystalline solids, notably halides, are presented.
TL;DR: The construction of a plasmid pLG609 is shown which carries the 3'‐end of the haemolysin structural gene, hlyA under tac promoter control, which appears to be all that is required for secretion of the whole toxin, which is so far quite unique in protein export.
TL;DR: In this article, the authors observed medium-scale travelling ionospheric disturbances (MSTIDs) at Leicester, U.K. (52°32′N 1°8′W) by means of the HF Doppler technique.
TL;DR: Results show that MB1 and MT1 are useful markers for B and T cells in routinely fixed paraffin embedded tissue and in conjunction with anti‐Leu M1 they provide a valuable panel of antisera for the examination of lymph nodes and other biopsies when frozen tissue is not available.
Abstract: The monoclonal antibodies MB1 and MT1, which detect B cells and T cells respectively, have been applied to human lymphoid tissues. The distribution of staining within paraffin sections was compared with that observed using frozen sections and was found to be identical. The antibodies were then applied to paraffin sections of 19 B-cell lymphomas and 10 T-cell lesions in which full immunophenotyping had been performed. The B lymphomas all consisted of a large majority of MB1 positive cells with a variable infiltrate of small MT1 positive lymphocytes. The T cell lesions consisted of MT1 positive cells with few MB1 positive cells except in residual B cell areas of lymph nodes. In paraffin sections from cases of Hodgkin's disease anti-Leu M1 identified Reed-Sternberg cells and their variants and MB1 and MT1 showed a similar distribution of B cells and T cells to that demonstrated in previous studies using frozen sections. The results show that MB1 and MT1 are useful markers for B and T cells in routinely fixed paraffin embedded tissue. In conjunction with anti-Leu M1 they provide a valuable panel of antisera for the examination of lymph nodes and other biopsies when frozen tissue is not available.
TL;DR: Assessment of laminin status, together with Dukes' stage is commended as a more precise and objective indicator of prognosis than histological degree of differentiation in colorectal carcinoma.
Abstract: Well-defined basement membrane laminin was seen in 98/158 (62%) rectal adenocarcinomas stained by an immunoperoxidase method. Only 27 (28%) patients with laminin-positive tumours developed distant metastases, compared with 39 (65%) patients with laminin-negative carcinomas. The corrected 5-year survival rates for patients with laminin-positive and laminin-negative tumours were 65% and 23%, respectively. Twenty-five out of 30 (83%) well-differentiated adenocarcinomas and only 3/15 (17%) poorly differentiated tumours contained basement membrane laminin, with moderately differentiated carcinomas showing intermediate laminin status (70/110, 64%, laminin positive). Forty-three of 60 (72%) of laminin-negative tumours had metastasized to regional lymph nodes. These data suggest that laminin may be a marker for differentiation. However, laminin status yields information about tumour behaviour which is not confined to stage and grade, and multivariate analysis shows that it is a better indicator of prognosis than tumour grade as assessed by conventional histology. Although laminin status alone is a less useful predictor of prognosis than Dukes' stage, a patient with a laminin-positive adenocarcinoma of rectum is 2.7 times as likely to survive 5 years than a patient with a laminin-negative tumour. Assessment of laminin status, together with Dukes' stage is, therefore, commended as a more precise and objective indicator of prognosis than histological degree of differentiation in colorectal carcinoma.
TL;DR: Overall poor activity of fluconazole in vitro corresponds badly with its high activity in animal models of mycoses in vivo, and provides more evidence for the unreliability of tests with azole antifungals in vitro as predictors of potential efficacy in vivo.
Abstract: Fluconazole is a novel triazole antifungal intended for oral treatment of superficial and systemic mycoses. In tests done in standard mycological media, the compound had minimal inhibitory concentrations against pathogenic Candida species that were usually in excess of 100 mg/l. By contrast, its 'relative inhibition factors' against Candida species (calculated from areas under the antifungal dose-response curves) were of the same order as those of other imidazole and triazole antifungal agents. Against pathogenic Aspergillus species and dermatophytes, the mean relative inhibition factors were the highest so far recorded for an azole antifungal, indicating a relatively weak inhibitory activity against these fungi. Fluconazole inhibited branching and hyphal development in C. albicans at concentrations as low as 10(-6) M (0.3 mg/l), but miconazole and ketoconazole were still active in these tests at concentrations 100 times lower than this. The new antifungal did not suppress ATP concentrations in C. albicans spheroplasts, in common with other weakly lipophilic azole antifungals. This overall poor activity of fluconazole in vitro corresponds badly with its high activity in animal models of mycoses in vivo, and provides more evidence for the unreliability of tests with azole antifungals in vitro as predictors of potential efficacy in vivo.
TL;DR: It is suggested that satellite DNA may have an impact on cell proliferation through the effect of late-replicating satellite-rich heterochromatin on the duration of S-phase of the cell cycle and even small alterations in cell cycle time may have magnified effects on organismal growth.
Abstract: The functional and evolutionary significance of highly repetitive, simple sequence (satellite) DNA is analysed by examining available information on the patterns of variation of heterochromatin and cloned satellites among newts (family Salamandridae), and particularly species of the European genus Triturus. This information is used to develop a model linking evolutionary changes in satellite DNAs and chromosome structure. In this model, satellites accumulate initially in large tandem blocks around centromeres of some or all of the chromosomes, mainly by repeated chromosomal exchanges in these regions. Centromeric blocks later become broken up and dispersed by small, random chromosome rearrangements in these regions. They are dispersed first to pericentric locations and then gradually more distally into the chromosome arms and telomeres. Dispersal of a particular satellite is accompanied by changes in sequence structure (for example, base substitutions, deletions, etc.) and a corresponding decrease in its detectability at either the molecular or cytological level. On the basis of this model, observed satellites in newt species may be classified as \`old', \`young', or of `intermediate' phylogenetic age. The functions and effects of satellite DNA and heterochromatin at the cellular and organismal levels are also discussed. It is suggested that satellite DNA may have an impact on cell proliferation through the effect of late-replicating satellite-rich heterochromatin on the duration of S-phase of the cell cycle. It is argued that even small alterations in cell cycle time due to changes in heterochromatin amount may have magnified effects on organismal growth that may be of adaptive significance.
TL;DR: In this article, the spin-lattice relaxation rate of the deuterons in 4-n-pentyl-d11-4′-cyanobiphenyld4 (5CB-d15) and 4n-pentyld1-4''-cyclic-cyclopentyl (5 CB-d1) was measured at 30·7 MHz and over the temperature range 257 to 400 K which includes the nematic-isotropic transition, T NI, at 308 K.
Abstract: The spin-lattice relaxation rates R (i) have been measured for the deuterons in 4-n-pentyl-d11-4′-cyanobiphenyl-d4 (5CB-d15) and 4-n-pentyl-d1-4′-cyanobiphenyl (5CB-d1) at 30·7 MHz and over the temperature range 257 to 400 K which includes the nematic-isotropic transition, T NI, at 308 K. Both samples display a small biphasic region because of the presence of a low concentration of an unknown impurity. The variation of both quadrupolar splittings and R (i) values have been carefully measured at 0·1 K intervals close to and in this interesting region. A discontinuity in the relaxation rate of the deuteron at the first position in the alkyl chain has been detected at T NI. The observed discontinuity is in good agreement with the change in R (i) predicted to occur because of the onset of long range orientational order at this temperature. There are regions of temperature in both phases where in R (i) varies linearly with T -1 and from which apparent activation energies can be determined for C-D bond reorient...
TL;DR: The results revealed that 14 out of 19 patients became dry after imipramine and six out of 14 after placebo treatment, which confirmed the great benefit of habit-retraining which all patients received.
Abstract: We compared imipramine with placebo in a double-blind study in Leicester, in elderly incontinent patients. The results revealed that 14 out of 19 patients became dry after imipramine and six out of 14 after placebo treatment. Patients on imipramine also tended to become drier sooner. However, these results must only be taken as preliminary evidence of drug effect since statistical analysis between drug and placebo did not reach significance. The results do, however, confirm the great benefit of habit-retraining which all patients received. It is now our practice to try this alone first, and to reserve drugs for slow or nonresponders, because of their possible adverse effects.
TL;DR: This paper identifies whether or not the slope of the regression line has continued to increase and suggests that for the group of countries as a whole, there is a worsening in the safety situation.
TL;DR: The structural and functional changes that occur at puberty are described, and what is known about the endocrine control of these changes in the human is summarized.
Abstract: The development of the human breast a t puberty involves morphologic and histologic changes which not only are interesting in their own right, but also may have important long-term effects on the breast’s subsequent susceptibility to malignant disease. In this article I shall first describe the structural and functional changes that occur at puberty, and then attempt to summarize what is known about the endocrine control of these changes in the human. Finally, the possible implications of pubertal development in the process of carcinogenesis will be discussed.