Showing papers by "University of Kansas published in 1974"

Total Hip Replacement

Abstract: Objective. —To provide physicians with a current consensus on total hip replacement. Participants. —A nonfederal, nonadvocate, 13-member consensus panel representing the fields of orthopedic surgery, rehabilitation and physical medicine, biomechanics and biomaterials, internal medicine, public health, geriatrics, biostatistics, and a public representative. In addition, 27 experts in orthopedic surgery, rehabilitation and physical medicine, biomechanics and biomaterials, rheumatology, geriatrics, and epidemiology presented data to the consensus panel and a conference audience of 425. Evidence. —The literature was searched through MEDLINE and an extensive bibliography of references was provided to the panel and the conference audience. Experts prepared abstracts with relevant citations from the literature. Scientific evidence was given precedence over clinical anecdotal experience. Consensus. —The panel, answering predefined consensus questions, developed their conclusions based on the scientific evidence presented in open forum and the scientific literature. Consensus Statement. —The panel composed a draft statement that was read in its entirety and circulated to the experts and the audience for comment. Thereafter, the panel resolved conflicting recommendations and released a revised statement at the end of the conference. The panel finalized the revisions within a few weeks after the conference. Conclusions. —Total hip replacement is an option for nearly all patients with diseases of the hip that cause chronic discomfort and significant functional impairment. Most patients have an excellent prognosis for long-term improvement in symptoms and physical function. At this time, a cemented femoral component using modern cementing techniques, paired with a porous-coated acetabular component, can give excellent long-term results. Revision of a total hip replacement is indicated when mechanical failure occurs. Continued periodic follow-up is necessary to identify early evidence of impending failure so as to permit remedial action before a catastrophic event. (JAMA. 1995;273:1950-1956)

Two entities in angiolipoma(A study of 459 cases of lipoma with review of literature on infiltrating angiolipoma)

Abstract: A study of lipomas collected over the past 20 years in a university hospital indicated that there are two types of angiolipoma, namely noninfiltrating and infiltrating Noninfiltrating angiolipoma is seen in young individuals and presents as painful, soft, cutaneous nodules Occasional compression of nerve fibers that accompany the vascular channels could be demonstrated Treatment is merely enucleation Infiltrating angiolipoma is rather rare Only 23 cases have been reported in the English literature Though histologically benign, the tumor can infiltrate bony, muscular, neural, and fibrocollagenous tissues to cause unusual symptoms and signs and can clinically simulate malignant neoplasms Wide excision to include the normal tissue surrounding the tumor is mandatory Radiotherapy should be rendered to cases with recurrence

Separation of parathyroid hormone and calcitonin-sensitive cells from non-responsive bone cells

Abstract: BONE growth and remodelling depend on resorption and deposition at the local level. The balance between these two processes seems to be modulated by the peptide hormones PTH and calcitonin. Parathyroid hormone (PTH) has been shown to induce bone resorption both in vivo1 and in vitro2, whereas calcitonin (CT) inhibits this process3. Recent studies suggest that both agents act on cellular mechanisms through a second messenger. Thus, it has been demonstrated that exposure of mouse calvaria to PTH or CT can lead to an increase in cyclic AMP content4,5. In addition, dibutyryl cyclic AMP can by itself induce bone resorption2.

Serum profiles of follicle-stimulating hormone, luteinizing hormone and prolactin during the estrous cycle of the hamster.

Abstract: Follicle-stimulating hormone (FSH), luteinizing hormone (LH) and prolactin concentrations were determined by radioimmunoassay (NIAMD-Rat RIA) of sera from intact hamsters, which were decapitated at selected times during the 4-day estrous cycle. Serum FSH concentrations on Day 1 of the cycle (day of ovulation) were 2- to 6-fold greater than the levels on Day 2 and 5 to 12-fold greater than the mean, “basal,” level of FSH (53 ± 2 ng/ml; 80 hamsters) found during Day 3 and until 1200 hr, Day 4. There was a biphasic serum FSH pattern on Day 4 (proestrus) which was demarcated by the initiation of the preovulatory surge at 1400 hr, the peak level at 1600 hr, the decay of the surge by 2100 hr, and the subsequent elevation to the high levels present on Day 1. In marked contrast to these changes in serum levels of FSH, LH levels were virtually constant throughout the estrous cycle, except for the preovulatory surge between 1300 hr and 1900 hr on Day 4 with a peak level at 1600 hr. Prolactin concentrations varied a...

Were workers of eusocial hymenoptera initially altruistic or oppressed

Abstract: Studies of a primitively eusocial halictid bee, Lasioglossum zephyrum, strongly suggest that a major factor in originating a worker caste is selection at the individual level for queens that control associated adult females. Even in this scarcely social form, the queen inhibits other adult females from becoming queens, perhaps by her high level of activity and frequent nudging in the nest. Queens are behaviorally less varied than workers and show specialization, particularly in frequency of nudging (which is concentrated on the worker with largest ovaries) and of backing. Backing draws workers, especially those with slender ovaries, down to lower parts of the burrows where the stimuli for cell construction and provisioning probably operate. Eating of worker-laid eggs by queens was also noted. In spite of the suggestion that queens have evolved to control their workers rather than that workers have evolved to help their queens, both may well have occurred, for these processes are not mutually exclusive; moreover, social attributes mutually beneficial to both castes no doubt have arisen.

Complete problems for deterministic polynomial time

Abstract: The results of Cook and Karp ([K], [C]) aroused considerable interest for at least two reasons. First, the answer to a long-standing open question which had seemed peculiar to automata theory—whether deterministic and nondeterministic polynomial-time-bounded Turing machines are equivalent in power—was seen to be exactly equivalent to determining whether any of several familiar combinatorial problems can be solved by polynomial-time algorithms. Second, the existence of complete problems for NP1 made it possible to replace an entire class of questions by a question about a single representative.Thus all of these combinatorial and automata-theoretic problems were essentially restatements of a single problem, such as: can satisfiability of a propositional formula be decided in polynomial time.The main purpose of this paper is to introduce several problems which are complete for P, the class of languages recognizable in deterministic polynomial time. Any such language has the property that if it is recognizable in space logk(•), then every language in P is so recognizable. Thus a problem complete for P will serve to differentiate those sets in P which are not recognizable in logarithmic space from those which are, providing such differentiation is possible. A problem of this type was first presented by Cook in [C2], concerning solvable path systems.

A Quasi-Vortex-Lattice Method in Thin Wing Theory

Abstract: A quasi-continuous method is developed for solving thin-wing problems. For the purpose of satisfying the wing boundary conditions, the spanwise vortex distribution is assumed to be stepwise-constant, while the chordwise vortex integral is reduced to a finite sum through a modified trapezoidal rule and the theory of Chebyshev polynomials. Wing-edge and Cauchy singularities are acounted for. The total aerodynamic characteristics are obtained by an appropriate quadrature integration. The two-dimensional results for airfoils without flap deflection reproduce the exact solutions in lift and pitching moment coefficients, the leading edge suction, and the pressure difference at a finite number of points. For a flapped airfoil, the present results are more accurate than those given by the vortex-lattice method. The three-dimensional results also show an improvement over the results of the vortex-lattice method. Extension to nonplanar applications is discussed.

Using preschool materials to modify the language of disadvantaged children.

Abstract: Although language remediation programs have generally been conducted with the use of special materials in structured group settings, traditional preschool practice emphasizes “incidental teaching” incorporated into children's free play. To determine if incidental teaching practices could be effective in improving children's speech, this study investigated the spontaneous speech of 12 disadvantaged children during free-play periods over eight months of a preschool program. Whenever the children selected a preschool play material, they were prompted and required to ask for it, first by name (noun), then by name plus a word that described the material (adjective-noun combination), then by use of a color adjuctive-noun combination, and finally by requesting the material and describing how they were going to use it (compound sentence). As each requirement was made, the children's general use of that aspect of language markedly increased, but little change was noted in the amount or nature of the children's interactions with teachers or their use of a set of materials to which they had free access. This study demonstrates that preschool free-play periods can be powerful “incidental teaching” periods by capitalizing on moments when children seek new play materials.

Pharmacokinetics of tolbutamide: Prediction by concentration in saliva

Abstract: The excretion of tolbutamide in saliva of diabetic patients receiving single intravenous doses of 1 gm tolbutamide is described. Gas chromatography with electron capture was used for analysis. Pharmacokinetic parameters could be obtained from either salivary or plasma tolbutamide levels. There was a good linear relationship between tolbutamide concentration in saliva and in plasma; salivary levels were 1.2% of plasma levels. Equations are presented that account for the excretion in saliva based on extent of protein binding and degree of ionization of tolbutamide in plasma and saliva. Correlation of the saliva to plasma concentration ratio was extended to data in the literature on two other drugs.

Periodicity in generations of automata

Abstract: A class of automata which build other automata is defined. These automata are called Turing machine automata because each one contains a Turing machine which acts as its computer-brain and which completely determines what its offspring, if any, will be. We show that for the descendants of an arbitrary progenitor Turing machine automaton there are exactly three possibilities: (1) there is a sterile descendant after an arbitrary number of generations, (2) after a delay of an arbitrary number of generations, the descendants repeat in generations with an arbitrary period, or (3) the descendants are aperiodic. We also show what sort of computing ability may be realized by the descendants in each of the possibilities. Furthermore, it is determined whether there are effective procedures for distinguishing between the various possibilities, and the exact degree of unsolvability is computed for those decision problems for which there is no effective procedure. Lastly, we discuss the relevance of the results to biology and pose several questions.

Radar measurement of soil moisture content

Abstract: The effect of soil moisture on the radar backscattering coefficient was investigated by measuring the 4-8 GHz spectral response from two types of bare-soil fields: slightly rough and very rough, in terms of the wavelength. An FM-CW radar system mounted atop a 75-ft truck-mounted boom was used to measure the return at 10 frequency points across the 4-8 GHz band, at 8 different look angles ( 0\deg through 70\deg ), and for all polarization combinations. A total of 17 sets of data were collected covering the range 4-36 percent soil moisture content by weight. The results indicate that the radar response to soil moisture content is highly dependent on the surface roughness, microwave frequency, and look angle. The response seems to be linear, however, over the range 15-30 percent moisture content for all angles, frequencies, polarizations, and surface conditions.

Localization of APP, a postulated new hormone, to a pancreatic endocrine cell type.

Abstract: APP is a polypeptide which has been isolated from avian pancreas and shown to exert pronounced biological effects. Immunofluorescence revealed APP to be present in the cytoplasm of numerous cells disseminated in the exocrine parenchyma of the chicken pancreas. The APP cells were polygonal or spindle-shaped and often had elongated processes in between the exocrine cells. The APP cells were particularly numerous at about hatching. They did not stain with methods demonstrating the three well-known islet cell types (A, B and D). The cells had the capacity to take up and decarboxylate l-dopa, a property shared with many polypeptide hormone-producing cell systems. Ultrastructurally, the APP cells had the appearance of polypeptide hormone-producing cells in that they contained numerous cytoplasmic granules Their granular morphology showed some resemblance but was not identical to that of the D cells.

A Measure for Circularity of Digital Figures

Abstract: It is demonstrated that ?R/?R, where R is a random variable of the distance between the center of the figure to any part of its perimeter, is a good measure for the circularity of a digital figure.

Cell death in the embryonic chick spinal cord.

Abstract: The events which occur in the death of visceromotor neurons of the cervical region of the chick embryo's spinal cord have been analyzed by electron microscopy. These normal degenerative events are compared with those in the lumbosacral cord where nerve cell death was induced by removal of peripheral organs. The initial set of degenerative changes include a decrease in nuclear size, the clumping of chromatin beneath the nuclear envelope, an increase in electron opacity of the cells, the disappearance of Golgi bodies, and the disaggregation of polysomes. These events are followed by the loss of the nuclear envelope and most of the endoplasmic reticulum, the appearance of bundles of filaments, and the formation of many ribosome crystals. Ribosome crystals are seen only in the dying cells. Their abundance may indicate a drastic reduction in RNA synthesis as one of the initial events which lead to the death of these neurons. The neurons are finally subdivided and engulfed by cells of the normal glial population, and further breakdown of the cell fragments occurs in large phagocytic vesicles of the gliocytes.

Immunity to feline toxoplasmosis: modification by administration of corticosteroids.

Abstract: Forty-nine cats were infected orally or parenterally with Toxoplasma gondii. The duration of oocyst shedding after primary infection was similar after single or multiple infection. After 2–32 weeks...

Training predelinquent youths and their parents to negotiate conflict situations.

Abstract: In response to parental requests for assistance in dealing with adolescent problem children, three parent-child pairs were taught negotiation responses to hypothetical conflict situations using behavior rehearsal and social reinforcement. The negotiation process was separated into component behaviors that were practised during simulations by each youth and his parent under the direction of trainers. Results indicated that (a) the procedures were successful in training youths and their parents in negotiation behaviors that produced agreements to conflict situations, and (b) these behaviors generalized to actual conflict situations in subjects' homes.

Nafenopin-induced hepatic microbody (peroxisome) proliferation and catalase synthesis in rats and mice. Absence of sex difference in response.

Abstract: Nafenopin (2-methyl-2[p-(1,2,3,4-tetrahydro-1-naphthyl)phenoxy]-propionic acid; Su-13437), a potent hypolipidemic compound, was administered in varying concentrations in ground Purina Chow to male and female rats, wild type (Csa strain) mice and acatalasemic (Csb strain) mice to determine the hepatic microbody proliferative and catalase-inducing effects. In all groups of animals, administration of nafenopin at dietary levels of 0.125% and 0.25% produced a significant and sustained increase in the number of peroxisomes. The hepatic microbody proliferation in both male and female rats and wild type Csa strain mice treated with nafenopin was of the same magnitude and was associated with a two-fold increase in catalase activity and in the concentration of catalase protein. The increase in microbody population in acatalasemic mice, although not accompanied by increase in catalase activity, was associated with a twofold increase in the amount of catalase protein. The absence of sex difference in microbody proliferative response in nafenopin-treated rats and wild type mice is of particular significance, since ethyl-α-p-chlorophenoxyisobutyrate (CPIB)-induced microbody proliferation and increase in catalase activity occurred only in males. Nafenopin can, therefore, be used as an inducer of microbody proliferation and of catalase synthesis in both sexes of rats and mice. The serum glycerol-glycerides were markedly lowered in all the animals given nafenopin, which paralleled the increase in liver catalase. All the above effects of nafenopin were fully reversed when the drug was withdrawn from the diet of male rats. During reversal, several microbody nucleoids were seen free in the hyaloplasm or in the dilated endoplasmic reticulum channels resulting from a rapid reduction in microbody matrix proteins after the withdrawal of nafenopin from the diet. Because of microbody proliferation and catalase induction with increasing number of hypolipidemic compounds, additional studies are necessary to determine the interrelationships of microbody proliferation, catalase induction, and hypolipidemia.

Male behaviour and territoriality in the Yellow-bellied marmot

Abstract: (With 1 plate and 8 figures in the text) Five populations of marmots were studied in Colorado from 1962 through 1972. Males are classified by age as yearlings, two-year olds, and adults. Socially, marmots are colonial, peripheral, or transient. Each population was divided into four age-sex classes, male yearlings, female yearlings, male adults, female adults, for analysis of social behaviour. Social behaviour was amicable or agonistic. Both types of behaviour occurred between male yearlings and each of the other age-sex classes. Play-fighting characterized social behaviour among male yearlings. Agonistic behaviour characterized social interactions between male yearlings and male adults. Male yearlings avoided male adults and usually dispersed from the locality. Adult male aggression enhanced but was not necessary for dispersal of yearling males. Agonistic behaviour between males and the four age-sex classes was not related to population density. Territorial males are conspicuous and advertise their presence by tail flagging. Many colonial males patrol their territory. Adult male social behaviour is predominantly agonistic. Mean rates of amicable and of agonistic behaviour between adult males and adult females were greater for years of male turnover than for years of male returns. Territoriality is characterized by exclusive use of the area by the colonial male, vigorous defence against transient or peripheral males, and by a relatively fixed area. A decrease in the number of males in an area causes an increase in the size of territories. Additional males in an area causes a decrease in the size of territories. The mean size of 24 typical territories is 0.67 ha. Reduction in the number of territories in an area was associated with increased agonistic behaviour among adult males. Fights were rare and occurred when the territorial system was unstable. The major functions of the territorial system are enhanced reproduction in a limited environment, enhanced outbreeding and enhanced fitness of colonial males.

Selection for blood pressure levels in mice

Abstract: Response to two-way selection for systolic blood pressure was immediate and continuous for about eight generations. In the twelfth generation, the High males differed from the Low males by 38 mmHG; the females differed by 39 mmHg. There was little overlap between the two lines and they were statistically significant from each other and from the Random control line. There appeared to be no more additive genetic variance in the eleventh and twelfth generations. Causes for the cessation of response are explored. This is probably due to a combination of natural selection acting to reduce litter sizes in the Low line, a higher incidence of sudden deaths in the High line, and loss of favorable alleles as both selection lines went through a population bottleneck in the ninth generation.—In the eleventh generation, the selected lines were used to produce F1, F2, and backcross generations. A genetic analysis yielded significant additive and dominance components in the inheritance of systolic blood pressure.