Showing papers by "National University of Singapore published in 1979"
TL;DR: Findings support the view that SCC, NKC, and UC of the nasopharynx, as defined in the WHO classification, are variants of a fairly homogeneous group of neoplasms in the Singapore population.
Abstract: A total of 363 cases of nasopharyngeal carcinoma (NPC) in Singapore were classified into squamous cell carcinoma (SCC; 73 cases), non-keratinizing carcinoma (NKC; 178 cases) and undifferentiated carcinoma (UC; 172 cases). Possible biological differences between these histologic types and between tumors with and without lymphocytic infiltration were investigated by correlations with survival rates and with selected epidemiologic, immunovirologic, and immunogenetic data on the disease. The 5-year survival rates following radiotherapy were 25.3% for all cases and 58.8% for tumors restricted to the nasopharynx. The 5-year survival rate for SCC was poorer than for the combined NKC and UC groups (p less than 0.05). The 3-year survival rate was better for tumors with lymphocytic infiltration (p less than 0.05), but there were no differences in the 5-year survivals. The survival rates were better in females (p less than 0.01) and in the younger age groups (p less than 0.01). There were no significant correlations between histopathology of NPC and the distributions of cases by age, sex, HLA antigen profiles, or cell-mediated immune status. Squamous cell carcinoma was associated with lower levels of antibodies to the Epstein-Barr nuclear antigen (p less than 0.05), but there were no differences with respect to antibodies against other EBV related antigens. These findings support the view that SCC, NKC, and UC of the nasopharynx, as defined in the WHO classification, are variants of a fairly homogeneous group of neoplasms in the Singapore population.
213 citations
TL;DR: It has been postulated that two types of this syndrome exist: a chronic form existing during pregnancy, and an acute form occurring only during parturitic pregnancy.
Abstract: bidity and mortality in twin pregnancies. 1-3 The weight difference between twin members presenting with this syndrome may be very marked in some instances; minimal in others. It has therefore been postulated that two types of this syndrome exist: a &dquo;chronic&dquo; form existing during pregnancy, and an &dquo;acute&dquo; form occurring only during parturitic~n.~ The large numbers of deliveries occurring in the Kandang Kerbau Hospital, Singapore, (about 25,000 annually) provided
87 citations
TL;DR: The successful use of inhibitors of prostaglandins to provide symptomatic relief for such reproductive disorders as dysmenorrhea and premature labor is discussed.
Abstract: PIP: Current information and theories about the role of prostaglandins in male and female reproduction are reviewed. Since more is known about prostaglandins in female reproduction, the activities of the substances in ovulation, luteolysis, anterior pituitary gonadotropin secretion, tubal contractility and egg transport, implantation, and uterine contractility are reported. Results of studies in animals and humans are cited in which prostaglandins are used to control reproduction. Finally, the successful use of inhibitors of prostaglandins to provide symptomatic relief for such reproductive disorders as dysmenorrhea and premature labor is discussed.
59 citations
TL;DR: In this paper, a set of useful statistical properties of measured radiation data is presented, showing the expected number of days in a year and in a given month of the year in which daily total radiation falls within a given range of values, and also the frequencies of occurrence of periods of successive days in which radiation is below specified values.
45 citations
TL;DR: In this article, a linear mapping on the space of n× nsymmetric matrices over a field F of characteristic not equal to two is presented. But the structure of the linear mapping is restricted to matrices of rank less than three.
Abstract: Let Tbe a linear mapping on the space of n× nsymmetric matrices over a field Fof characteristic not equal to two. We obtain the structure of Tfor the following cases:(i) Tpreserves matrices of rank less than three; (ii) Tpreserves nonzero matrices of rank less than K + 1 where Kis a fixed positive integer less than nand Fis algebraically closed; (iii) Tpreserves rank Kmatrices where Kis a fixed odd integer and Fis algebraically closed.
38 citations
TL;DR: Streptozotocin administered i.m. was as effective a diabetogenic agent as when administered iV, particularly for the induction of diabetes in small animals.
Abstract: Streptozotocin administered i.m. was as effective a diabetogenic agent as when administered i.v. This is useful, particularly for the induction of diabetes in small animals.
30 citations
TL;DR: A functional role for the ADLC antibodies is suggested by the association of a high ADLC antibody titre with a good prognosis regardless of stage of disease.
Abstract: Antibody titres to EBV-associated antigens in Chinese NPC patients were analysed according to length of survival after diagnosis and to disease stage. Geometric mean titres of ADLC antibody were highest in the long-term survivors, whereas VCA, EA and EBNA antibody titres showed an inverse relationship to survival. High VCA, EA and EBNA titres were less frequent, and high ADLC titres were more frequent in long-term survivors than in intermediate or short-term survivors. The association of geometric mean titres of EBV antibodies with prognosis could not be entirely explained by stage of disease. A functional role for the ADLC antibody is suggested by the association of a high ADLC antibody titre with a good prognosis regardless of stage of disease.
28 citations
Federal University of Bahia1, Siriraj Hospital2, Post Graduate Institute of Medical Education and Research3, University of Western Ontario4, University of Southern California5, University of Zambia6, University of Chile7, Seoul National University8, National University of Singapore9, Karolinska University Hospital10, University of Sydney11
TL;DR: Variations in metabolism of orally administered norethisterone appeared not to be due to variations in body size, and was of the same order as the intra-centre differences.
25 citations
24 citations
TL;DR: It is suggested that the procedure described by Savage and Davey has been a most successful procedure in providing reliable and safe method of closure of gastroschisis, avoiding the complications and morbidity of staged closure using prosthetic material.
Abstract: A review of gastroschisis treated at the Royal Alexandra Hospital for Children, Sydney, in the ten years between 1967 and 1976, was carried out. Early postoperative deaths occurred in those with poor general condition before and immediately after the operation. The presence of a gastrostomy appears to be most effective in the immediate postoperative period to assist in decreasing intraabdominal pressure. The results of three initial operative methods are discussed. The three procedures are the Gross method; prosthetic closure; and the Savage and Davey method of transverse incision and closure. The purpose of this paper is to suggest that the procedure described by Savage and Davey has been a most successful procedure in providing a reliable and safe method of closure of gastroschisis, avoiding the complications and morbidity of staged closure using prosthetic material.
24 citations
TL;DR: The pathology of four types of chondrodysplasias, viz., type II achondrogenesis, thanatophoric dwarfism, Saldino-Noonan syndrome, and chondRodysplasia punctata were studied and cells with features similar to the chief and dark chondrocytes of normal hyaline cartilage were seen to be altered in different ways.
Abstract: The pathology of four types of chondrodysplasias, viz., type II achondrogenesis, thanatophoric dwarfism, Saldino-Noonan syndrome, and chondrodysplasia punctata were studied. In each of these disorders, cells with features similar to the chief and dark chondrocytes of normal hyaline cartilage were seen to be altered in different ways. There was a total absence of chief cells in type II achondrogenesis. All the chondrocytes present were of one variety at different states of maturation, with the fully matured cell having features of dark chondrocytes. The absence of chief cells was associated with marked diminution of interlacunar matrix and failure of growth plate development. The chief chondrocytes in thanatophoric dwarfism appeared diminished in number. They were probably abnormal functionally as evident by their lack of cytoplasmic vacuolation and the formation of thick, occasionally branched collagen in the matrix. The growth plate was stunted and poorly developed. Striking changes involving the dark cells were noted in Saldino-Noonan syndrome, where unusually elongated dark cells were found in groups within abnormal cystic spaces. The chief cells were large and contained abnormal cytoplasmic filaments. There was no formation of a growth plate. In chondrodysplasia punctata, the chief cells were enlarged and abnormally vacuolated. The matrix showed excessive aggregates of coarse granular material. In addition, there were focal accumulations of highly abnormal chief and dark cells with abnormal matrix which contained increased amount of keratan sulphate and culminated in spotty calcification.
TL;DR: 406 women--about one-fifth of those requesting an induced abortion and sterilisation over a thirty-three-month period--volunteered to be allocated randomly to either a concurrent induced-abortion/sterilisation group or a group which was sterilised six weeks after abortion.
TL;DR: The concentration of free choline and cephalin‐N‐methyltransferase activity were determined for the rat maternal and foetal liver and placenta during gestation, and for the maternal and neonatal liver during the early postpartum period.
Abstract: Summary
1. The concentration of free choline and cephalin-N-methyltransferase activity were determined for the rat maternal and foetal liver and placenta during gestation, and for the maternal and neonatal liver during the early postpartum period. Choline was determined by bioassay and the enzyme activity by using S-adenosyl-L-(14C-methyl)-methionine.
2. There was a significant and progressive fall in the choline concentration (nmol/g tissue) of the maternal liver from the control value of 130 (s.e.m. = 9) to 93 (s.e.m. = 9) after about 11 days gestation and to 38 (s.e.m. = 1) from about 17 days gestation to term; however, there was a gradual rise in the corresponding enzyme activity (counts/min) from a mean value of 561, s.e.m. = 7, (control to 618 (s.e.m. = 14) and then to 693 (s.e.m. = 19).
3. At 1 day postpartum both the choline concentration (166, s.e.m. = 9) and the enzyme activity (738, s.e.m. = 45) of the maternal liver increased appreciably and reached a peak before gradually declining to the control value at about 3 and 7 days postpartum, respectively.
4. The hepatic choline concentration of the foetus at 20 to 22 days gestation (135, s.e.m. = 6) was similar to adult (control) levels, although its cephalin-N-methyltransferase activity was very low (about 20% of control).
5. The choline concentration of the neonatal liver increased to 220 (s.e.m. = 21) and then to 272 (s.e.m. = 17) at 1 day and at about 3 days postpartum followed by a decline to the adult (control) value at about 7 days postpartum. The enzyme activity, however, increased continuously to attain adult levels at about 10 days postpartum.
6. The placental choline concentration was about three to four-fold greater than that of the control liver. The values obtained were 370, s.e.m. = 27 (14 to 16 days gestation), 426, s.e.m. = 27 (17 to 19 days gestation) and 442, s.e.m. = 18 at term. However, the cephaline-N-methyltransferase activity was undetectable in the placentae.
7. The choline concentration of the maternal plasma(5.3, s.e.m. = 0.7) remained essentially constant throughout gestation and in the early postpartum period.
8. The results strongly suggest that, during pregnancy, the rat maternal liver supplies free choline to the placenta and foetal liver and that the demand for maternal liver choline probably exceeds the supply available.
TL;DR: It is suggested that flowering in this orchid hybrid is regulated by growth substances, both qualitatively and quantitatively.
Abstract: Summary
The growth habit, axillary bud differentiation and flowering behaviour in a sympodial orchid hybrid, Dendrobium Louisae cv. ‘Dark’ were studied. Flowering occurred only after termination of vegetative growth in the pseudobulb. Intermediate shoots with both vegetative and reproductive growth were produced when plants were placed in the shade. Decapitation did not stimulate floral initiation. In mature pseudobulbs, Cytokinin (benzyladenine) stimulated flowering. Gibberellic acid enhanced the cytokinin effect but was itself not effective. It is suggested that flowering in this orchid hybrid is regulated by growth substances, both qualitatively and quantitatively.
TL;DR: Electron microscope study showed that some of these phagocytic cells carried intracytoplasmic carbon particles, which are believed to be derived from circulating monocytes which have ingested carbon particles in circulation and thereafter invaded the stab wound.
Abstract: Colloidal carbon was introduced intravenously into young rats to label circulating monocytes before the stabbing of the brain. The rats were sacrificed 1 to 14 days after the stab wound. In the rats sacrificed between 3 to 7 days after the stabbing, numerous phagocytic cells were present in the needle wound. Electron microscope study showed that some of these phagocytic cells carried intracytoplasmic carbon particles. These carbon-labelled cells showed features either of a monocyte, full-blown macrophages, or typical microglia. It is believed that they are all derived from circulating monocytes which have ingested carbon particles in circulation and thereafter invaded the stab wound.
TL;DR: In this article, a warehouse construction in Singapore, 3 m to 4.5m depth of peaty clay overlain by 3.5 m to 6 m of medium silty clay posed a problem for the foundation construction.
Abstract: For a warehouse construction in Singapore, 3 m to 4.5 m depth of peaty clay overlain by 3.5 m to 6 m of medium silty clay posed a problem for the foundation construction. In order to avoid excessive settlements for the foundation and the floor slab, the methods available were to drive piles to a good bearing and suspend the flooring or to replace the highly compressible peaty clay with a better soil type which could be compacted to receive the spread footings and flooring slab. For the small column and floor loads involved, both these approaches were found to be expensive and the latter method was also impractical for the site conditions. The method of applying high energy impacts on the top of the silty clay layer overlaying the peaty clay was adopted in order that the improvement in strength and compressibility characteristics could be brought about for the peaty clay to the desired levels.
TL;DR: The results suggest that Clomiphene acts as an anti‐oestrogen in uncastratedmale transsexuals and in castrated male transsexuals who have subphysiological levels of oestradiol it acts as a weak oestrogen.
Abstract: SUMMARY
Clomiphene was administered at a daily dose of 100 mg for 5 consecutive days to two groups of male subjects. There were three uncastrated male transsexuals (Group A) and nine castrated male transsexuals (Group B). In the uncastrated subjects Clomiphene enhanced the secretion of follicle-stimulating hormone (FSH), luteinizing hormone (LH) and testosterone (T) starting from day 3 of treatment. The magnitude of the increment ranged from 150%–250% over the mean basal plasma level for LH, 113%–262% for FSH and 12%–68% for T. In contrast, Clomiphene suppressed both FSH and LH in the castrated subjects. Equal suppression of both the gonadotrophins were observed. The levels of FSH and LH in plasma on day 3 were suppressed to 66.4% and 66.2% of their respective mean basal levels. Two days after the termination of treatment, suppressions were maintained. These results suggest that Clomiphene acts as an anti-oestrogen in uncastrated male transsexuals and in castrated male transsexuals who have subphysiological levels of oestradiol it acts as a weak oestrogen.
TL;DR: In this article, a treatment of the mixed boundary value problem that arises in determining the spreading resistance of an inhomogeneous slab backed by a perfectly conducting substrate is presented, where the inhomogeneity enters into the problem through the weight function of a pair of dual integral equations, and this function is the same as the integration factor that occurs in previous approximate solutions based on assumed source current distributions.
Abstract: This paper presents a treatment of the mixed boundary value problem that arises in determining the spreading resistance of an inhomogeneous slab backed by a perfectly conducting substrate. It is shown that the inhomogeneity enters into the problem through the weight function of a pair of dual integral equations, and that this function is the same as the integration factor that occurs in previous approximate solutions based on assumed source current distributions. Except for the difference in the weight function, the dual integral equations are similar to those for the homogeneous slab. Calculations are performed for structures with exponential resistivity profiles, and the results used to determine the accuracy of three approximate methods currently available for spreading resistance calculations on semiconductor device structures.
TL;DR: In this paper, it was shown that the spaces (L1, Lip(α, p)), (L 1, A, L 1, A, p), (L 2, A, p ), (L 3, p), Lip( α, p) and lip( p) are isometrically isomorphic.
TL;DR: The effect of three different doses (12.5 μg, 25 μg and 50 μg) of 17 phenyl PGF2α on nasal patency in fourteen patients with vasomotor rhinitis was studied.
TL;DR: In this paper, a few types of commercially available grinding fluids and the introduction of certain types of elements which may enhance wheel performance were examined. And the authors found that by introducing colloidal graphite into the grinding fluid, wheel efficiency was improved in terms of higher G -ratios.
TL;DR: The results suggest that some of the inter-m-phenylene analogues of PGE1 may be bronchodilators in asthmatics.
TL;DR: In this article, the authors present experimental results at X-band for a short backfire antenna with corrugated rim, which is excited by a rectangular waveguide, and show that the use of the waveguide feed can lead to a compact antenna having a directive gain of 20dB, sidelobe levels of - 17 dB and v.w.r.
Abstract: The letter presents experimental results at X-band for a short backfire antenna with corrugated rim, which is excited by a rectangular waveguide. It is shown that the use of the waveguide feed can lead to a compact antenna having a directive gain of 20dB, sidelobe levels of - 17 dB and v.s.w.r. in the range 1.1-2.
TL;DR: In this paper, an experimental study at X-band of a dipole-excited short backfire antenna having corrugations on the main reflector rim was conducted. The results obtained show that the presence of the corrugation can lead to improved antenna gain and sidelobe levels.
Abstract: This letter reports results of an experimental study at X-band of a dipole-excited short backfire antenna having corrugations on the main reflector rim. The results obtained show that the presence of the corrugations can lead to improved antenna gain and sidelobe levels.
TL;DR: The present paper is concerned with the cytohistological changes within the apex resulting from flower induction by the use of acetylene, NAA, and ethephon.
Abstract: The vegetative apex of the Masmerah cultivar of pineapple, Ananas comosus (L.) Merr., is domeshaped and has the typical tunica-corpus organization. Treating the plant with acetylene, NAA or ethephon transforms the vegetative apex to a reproductive one. As early as two days after treatment the apical height and width increase, attaining maximum dimensions in 8-14 days, after which they progressively decrease. During 4-6 weeks, when the full complement of florets has been initiated, the dimensions of the apex are again increased and leaves that form the fruit crown are initiated. A cambium-like zone at the base of the corpus is noticed 2-4 days after the application of acetylene and ethephon. Acetylene and NAA result in a more pointed apex initially, while ethephon results in a more broadened apex. The largest increase in apical height and width is seen when NAA is used. The development of the inflorescence from the time the full complement of florets is formed to fruit maturity is described. Cell multiplication is the main cause of peduncle elongation and inflorescence head enlargement, although towards the later stages of growth, cell enlargement contributes more to the increase in size of the organs. THE USE of wood smoke to induce premature flowering in pineapple plants originated in the Azores Islands during the late eighteenth century (Collins, 1960). Research by Rodriguez (1932) led to the identification of the unsaturated hydrocarbon gases in the smoke as the active ingredients. In subsequent experimentation, acetylene (Kerns, 1936) and calcium carbide were used (Wendt, 1936). The effectiveness of plant growth hormones was later investigated and among those found beneficial were NAA, 1-naphthaleneacetamide, 1-naphthalenethioacetamide (Clark and Kerns, 1942), and 2,4-D (Van Overbeek, 1946). Subsequent research led to the identification of more than 100 chemicals effective in inducing flowering (Gonzalez, 1956; Gowing, 1956, 1958; Gowing and Leeper, 1955, 1960a,b, 1961a,b). A new growth regulator in the form of 2-chloroethanephosphonic acid (ethephon) was discovered (Cooke and Randall, 1968) and it was found to induce early and uniform flowering as well as fruiting (Py and Guyot, 1970; Wee and Ng, 1971). Currently the more popular chemicals used to induce flowers in pineapple are acetylene and NAA. Ethephon is slowly gaining popularity, for although it is as effective, if not more so than the other two chemicals, it is relatively more expen1 Received for publication 4 April 1978; revision accepted 1 November 1978. We wish to express our appreciation to Miss Tay Guat Meng, Miss Phua Kui Phoon, Mrs. M. Goh and Mr. D. Teow for their technical help and to Mr. Chew Key Szu for statistical computations. sive. In West Malaysia, acetylene is more effective than NAA although the use of the latter results in heavier fruits (Wee and Rao, in press). Despite this, NAA is widely used among the small growers as it is convenient to apply and store, while in larger farms acetylene is favored. Earlier workers have studied the development of the inflorescence (Kerns, Collins, and Kim, 1936), anatomy and histology of the inflorescence and fruit (Okimoto, 1948), vegetative shoot apex and the cytological changes after treatment with acetylene (Gifford, 1969); recently Bartholomew (1977) described the vegetative apex by use of electron microscopy after treatment with ethephon. The present paper is concerned with the cytohistological changes within the apex resulting from flower induction by the use of acetylene, NAA, and ethephon and the subsequent development of the apex to fruit maturity. This is partially in response to Gifford's (1969) suggestion that comparisons between plants flowering under natural conditions and as a result of acetylene, or ethylene and auxin treatments might prove interesting. MATERIALS AND METHODS-Vegetative apices of seedlings, crowns (shoot-like growths developing from the top of fruits), and slips (shoots arising from peduncles) of Ananas comosus (L.) Merr. cv. Masmerah were collected during the morning and immediately fixed in FAA. In the case of crowns and slips, apices were taken at the time of fruit harvest when the plants were
TL;DR: A partially purified toxin obtained from the coral reef crab, Lophozozymus pictor was found to be a potent inhibitor of Na+-dependent [14C]-GABA uptake by rat brain synaptosomes.
TL;DR: A simple, inexpensive and sensitive method of detecting alpha-fetoprotein by supplementation CIE assay is described, detecting AFP at concentrations in the region of 20 ng/ml.