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Biomedical subjects

L Williams

Publications and source records attributed to L Williams.

At least 343 records · Page 19Linked to original sources
PubMed1981

Human antithrombin III heterogeneity.

Crossed immunoelectrophoretic patterns were obtained on three patients with a congenital deficiency of anti-thrombin III (AT-III), and on normal single donor and "pooled" plasma controls. In the presence of heparin (incorporated into the agarose gel matrix), the AT-III of normal human plasma was separated into four components: two major, faster-moving components, and two minor, slower-moving components. The three patients with congenital deficiency of AT-III (levels approximately 50% of normal) appeared to possess only one of the faster-moving components, and one of the slower-moving components.

Antithrombin III↗
PubMed1980

Growth cones in differentiated neuroblastoma: a time-lapse cinematographic and electron microscopic study.

Growth cones of 'differentiating' neuroblastoma cells in monolayer culture were studied by time-lapse cinematography and electron microscopy. Morphological differentiation, and thus growth cone formation, was induced by the glucocorticoid dexamethasone. Growth cones lengthened gradually at an average rate of 30 microns/h, advancing in stages that involved alternating extensions and retractions of the filopodia and lamellar sheets. During neurite growth the cell body usually remained stationary. The ultrastructure of growth cones was typified by several filopodia, each containing a bundle of microfilaments, agranular endoplasmic reticulum, aggregates of large agranular vesicles lying adjacent to filopodia (previously termed vesicle-filled mounds), many dense-cored vesicles, 100-140 nm in diameter, microtubules, bizarre and distorted mitochondria, and scattered from ribosomes. Comparing the findings with previous ultrastructural accounts of growth cones of cultured ganglion cells, similarities outnumbered differences. The organization of the microfilament bundles and the abundance of free ribosomes were remarkable in the neuroblastoma cell as was the profusion of dense-cored vesicles which were most numerous in the proximal portion of the growth cone.

Animals↗
PubMed1980

A controlled study of the results of femoral osteotomy in severe Perthes' disease.

We compared 63 hips (Catterall Groups 3 and 4) contained by femoral osteotomy with 85 untreated hips and found that 50.7 per cent of treated patients developed congruous spherical femoral heads in contrast to 14.1 per cent of those untreated. We have also considered certain other features relevant to the outcome. We suggest that the indications should not be modified on the grounds of early age of onset. Relief from weight-bearing does not appear to improve the results of containment. We have assessed the shortening which follows femoral osteotomy and conclude that this is only significant when there is growth disturbance at the capital epiphysis. These changes are at least as frequent in untreated patients.

Adolescent↗
PubMed1980

The inhibition of high and low molecular weight urokinase in plasma.

The rates of inhibition of high molecular weight (HMW) and low molecular weight (LMW) urokinase (UK) incubated in plasma or with purified antithrombin III (AT-III) were compared. Using a fibrinolytic assay system to determine residual biologic activity, polyacrylamide gel electrophoresis to demonstrate the formation of complexes, and selective immunoprecipitation techniques to identify the plasma inhibitors participating in the neutralization process, it was established that: (A) HMW-UK is inhibited more rapidly than LMW-UK, both in plasma and with purified AT-III; (B) heparin (3--10 U/ml accelerates the neutralization process in both systems, but only slightly; and (C) in plasma, several inhibitors, alpha 2-macroglobulin, alpha 1-antitrypsin, and antithrombin III, neutralize the activity of HMW-UK and LMW-UK.

Animals↗
PubMed1979

Characteristics of intraluminal pressure sensing balloons of different materials.

The physical properties of the balloons made of some polymeric substances were studied. The polyurethanes provided high frequency characteristics but air-leaking disqualified except ECD-651 which was most satisfactory: low permeability and ease of fabrication. Saran was proper but troublesome in making the balloon. Polypropylene and polyethylene, available in film, required heat sealing, which resulted in deformity and low frequency characteristics.

Intestines↗
PubMed1979

Histochemical demonstration of alkaline phosphatase in human large intestine, normal and diseased.

Alkaline phosphatase activity has been investigated by histochemical methods in normal and diseased human large intestine. The tissues were constantly maintained at 4 degrees C or below. Specimens were either frozen in liquid nitrogen, freeze-dried and embedded in glycol methacrylate for sectioning at 2 mu, or, fixed in ice-cold formol-calcium for frozen sectioning at 10 mu. The simultaneous coupling azo dye method using the substrates sodium alpha-naphthyl phosphate and Naphthol AS-BI phosphate, resulted in the demonstration of alkaline phosphatase activity in the surface epithelial cells, and the middle and upper crypts, of normal and transitional mucosa.

Alkaline Phosphatase↗
PubMed1979

Infant behavioral state and speech sound discrimination.

In order to investigate the interaction between infant state and speech sound discrimination, records of state were obtained from infants participating in 3 speech sound discrimination experiments which employed the high amplitude sucking procedure. A total of 94 individual records were rated for state by 2 independent scorers. When treated as an independent variable, state interacted with responsivity to sound change as measured by sucking rate increases. Infants in the more alert states demonstrated significantly higher rates of sucking following sound change. Treating state as a dependent variable revealed that state was not significantly affected by a change in stimulus conditions.

Arousal↗
PubMed1979

An analysis of the components of the pulmonary shunt equation: significance of the alveolar-arterial oxygen gradient, arterio-venous oxygen content difference, and mixed venous oxygen pressure.

Pulmonary shunt calculated by the Berggren method is commonly used as an indicator of pulmonary function. Although there is usually a good correlation between the shunt and the A-aDO2, other physiologic parameters involved in the shunt equation may significantly alter pulmonary function. The purpose of this study is to show the contribution of the PVO2 and a--v diff to the shunt equation. Data from eight selected patients with A--aDo2 values ranging from 300 to 395 torr and calculated shunts ranging from 6 to 35% were selected for this purpose. In patients with significant changes in PVO2 and a--v diff, the A--aDO2 is more reliable as an indicator of pulmonary function than is the calculated shunt.

Humans↗
PubMed1978

Phosphorus-nitrogen compounds. 21. Murine oncolytic and antifertility effect of adamantylaziridine compounds.

P,P-Bis(1-aziridinyl)-N-adamantylphosphinic amide and N,N'-bis(ethylene)-P-(1-adamantyl)phosphonic diamide were synthesized as potential anticancer and male antifertility agents. Log P values (octanol-water) of the agents were determined and compared to calculated values. Both derivatives displayed intraperitoneal murine antileukemic activity and antifertility effects when given intraperitoneally and orally.

Adamantane↗