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51.
Lightbody James J. Peterson Ward D. Poulik M. D. 《In vitro cellular & developmental biology. Plant》1978,14(5):465-468
Summary The DAUDI lymphoblast cell line derived from a patient with Burkitt lymphoma was obtained from two different sources. One
of these (DAUDI-I) produced a factor that inhibited lymphocyte proliferation in both human and mouse regardless of the stimulator,
i.e. allogeneic lymphocytes or mitogens. Glutaraldehyde treatment eliminated production of the factor and demonstrated that
DAUDI-I was capable of stimulating normal lymphocytes in MLR. A second DAUDI cell line (DAUDI-S) did not produce the inhibitory
factor and was capable of MLR stimulation.
Supported by the Children's Leukemia Foundation of Michigan, NIH Grants AI 11013 and AI 11335, and the Kidney Foundation of
Michigan. 相似文献
52.
Association with sludge solids did not allow poliovirus to enter cells other than through the normal receptor-mediated route. This implies that the infectivities of sludge-encapsulated virions are masked until their exposure permits binding to cell surface receptors. 相似文献
53.
C M Ward 《Plastic and reconstructive surgery》1979,64(1):68-75
A system for subjective and objective clinical analysis of the lower third of the nose before and after lengthening the columella was devised, and used the study of photographs of 77 patients who had had lengthening done by one of 4 approaches. It was found that each method was equally effective in lengthening the columella and in restoring a normal relationship between the structures in the tip of triangle (the basal view of the nose). However, there were certain peculiar advantages and disadvantages of each surgical technique, and these are discussed. 相似文献
54.
Composition, stability and electrolyte permeability of Golgi membranes from lactating-rat mammary gland. 总被引:1,自引:1,他引:0 下载免费PDF全文
1. Golgi membrane vesicles, isolated from lactating-rat mammary gland and greatly enriched in galactosyltransferase (EC 2.4.1.22), contained over 40 separate bands of protein, including some periodic acid)(Schiff-staining material and free thiol groups, when analysed by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis. 2. The membrane lipids were enriched in phosphatidylcholine, phosphatidylethanolamine and unesterified cholesterol. 3. Membrane fluidity, as monitored by the fluorescence polarization of 1,6-diphenylhexa-1,3,5-triene, increased linearly over 5-37 degrees C. 4. The vesicle membranes were impermeable to lactose over a wide pH range, but admitted electrolytes of molecular weight below about 300. 5. These properties are discussed with respect to other cellular membranes and the secretion of milk products. 相似文献
55.
Evolution of the Hong Kong influenza A sub-type. Structural relationships between the haemagglutinin from A/duck/Ukraine/1/63 (Hav 7) and the Hong Kong (H3) haemagglutinins. 总被引:3,自引:0,他引:3 下载免费PDF全文
The relationship between the haemagglutinin from the influenza virus A/duck/Ukraine/1/63 (Hav 7) and the human Hong Kong variants (H3) has been investigated. Amino-acid-sequence analysis shows that the Hav 7 haemagglutinin closely resembles the 1968 human H3 haemagglutinin in structure. However, the number of amino-acid-sequence differences (23) suggest that the Hong Kong haemagglutinin gene did not come directly from A/duck/Ukraine/1/63 but from a virus derived from it by antigenic drift during the period 1963-1968. 相似文献
56.
Richard L. Rapport II George A. Ojemann Allen R. Wyler Arthur A. Ward Jr. 《The Western journal of medicine》1977,127(3):185-189
Therapy with anticonvulsant drugs reduces the frequency and severity of seizures in many but not all epileptic patients. Unfortunately, in a significant number control remains poor even when maximal doses of multiple anticonvulsant drugs are given. Some of these patients are candidates for surgical treatment of epilepsy. The operative management of convulsive disorders is a well-established technique and is available in some centers. In selected cases, such operations are both safe and effective, with good longterm improvement or complete control in 76 percent of patients. We have summarized the 24-year experience with surgical operation for epilepsy at the University of Washington Medical Center. 相似文献
57.
The origin of protein and fatty yolk in Rana pipiens. III. Intramitochondrial and primary vesicular yolk formation in frog oocytes. 总被引:1,自引:0,他引:1
R T Ward 《Tissue & cell》1978,10(3):515-524
The precise origin of the primary yolk precursor complex or primary vesicular yolk is obscure but in its earliest recognizable stage it is a typical multivesicular body which first acquires a moderately electron-dark matrix. Following this, an extremely electron-dark amorphous material, the yolk protein, appears within the precursor. This yolk protein increases in amount as the yolk vesicle grows and by the time the precursors are about 1 micrometer in diameter this protein is partly to almost completely crystalline. Yolk originating within mitochondrial cristae unlike that in the yolk precursor complexes is crystalline from its earliest appearance. Intracristae mitochondrial yolk crystals have a spacing of 70--85 A. Their molecular organization appears in some sections as electron-dark lamellae and in others as light cylinders surrounded by an electron-dark matrix. 相似文献
58.
59.
D M Ward 《Applied and environmental microbiology》1978,35(6):1019-1026
Algal-bacterial mats which grow in the effluent channels of alkaline hot springs provided an environment suitable for studying natural thermophilic methane producing bacteria. Methane was rapidly produced in cores taken from the meat and appeared to be an end product of decomposition of the algal-bacterial organic matter. Formaldehyde prevented production of methane. Initial methanogenic rate was lower and methanogenesis became exponential when samples were permitted to cool before laboratory incubation. Methanogenesis occurred and methanogenic bacteria were present over a range of 68 to 30 degrees C, with optimum methanogenesis near 45 degrees C. The temperature distribution of methanogenesis in the mat is discussed relative to published results on standing crop, primary production, and decomposition in the thermal gradient. The depth distribution of methanogenesis was similar to that of freshwater sediments, with a zone of intense methanogenesis near the mat surface. Methanogenesis in deeper mat layers was very low or undetectable despite large numbers of viable methanogenic bacteria and could not be stimulated by addition of anoxic source water, sulfide, or a macronutrient solution. 相似文献
60.
Aggressive interactions of male Sarotherodon melanotheron were studied to determine the communicative value of chin spot size in relation to dominance. In addition, the effects of residency and size on the aggressiveness of this fish were determined. Two-factor analysis of variance was used for frequencies of each modal action pattern for residency and size. Results show that residency played a major role in the outcome of an aggressive interaction, whereas size had little effect. Dominance of each experimental fish was calculated using Barlow & Ballin's (1976) dominance index. A chin spot ratio was obtained by dividing the chin spot area by the total surface area of the individual fish. Simple linear regression was conducted to determine if dominance and chin spot size were correlated and a positive linear relationship was found to exist between the two variables. 相似文献