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This report that (1) cells mediating NK activity in different inbred mouse strains selectively express one of two allelic products specified by theLy-5 locus (or a locus tightly linked to it) and (2) this surface structure may directly contribute to NK-mediated cytolysis, since Ly 5 antiserum specifically inhibits NK activity in vitro in the absence of complement. 相似文献
145.
Summary
Allolobophora rosea (Savigny) was found to be common in mull type soils beneath bramble (Rubus fruticosus L.). Burrow construction in this soil type in the laboratory at 4.4, 10.0 and 14.8°C ranged between 133 and 516 mm g-1 fresh wt of worm day-1. Burrowing was affected by both body size and temperature. Rates of soil displacement during burrowing were estimated from burrowing rates, burrow dimensions and soil density; depending on body size and temperature they were in the range 809–1,928 mg dry wt of soil g-1 fresh wt of worm day-1. These values were in reasonable agreement with measured egestion rates (range: 1,000–2,000 mg dry wt of egesta g-1 fresh wt of worm day-1). It was concluded that A. rosea eats its way through the soil and is adapted to its rapid turnover. Gut turnover times were calculated to be between 1 and 2.5 h.Direct observation indicated that feeding was by a grazing procedure and it was shown that A. rosea preferentially selects the more organic fractions of the soil for ingestion.The evaluation of energy budgets for individual small immature, large immature and adult worms at 10°C revealed respiration to production ratios (R/P) of 1.0, 1.8 and 4.1, respectively. Assimilation efficiencies (A/C) were always less than 2.5%. 相似文献
146.
Twenty-two patients with cutaneous vascular malformations were treated with an argon laser. Promising results were obtained in patients with port-wine stains, hemangiomas, telangiectasia and varicose veins. The argon laser shows promise as an effective clinical tool in the treatment of all such cutaneous vascular abnormalities. However, further study of clinical as well as laboratory data is necessary over a long period of time before this modality can be definitely recommended as the treatment of choice for vascular deformities of the skin. 相似文献
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Purified Photosystem I particles from spinach when reduced with 10 mM dithionite at pH 9 exhibited a 50% light reversible-ESR Signal 1 (P-700+) at about 10 K. It was possible to show by signal-averaging techniques that a light-reversible ESR spectrum concomitant with the reversible Signal 1 can be observed with approximate principal g factors at g = 2.07, g = 1.86 and g = 1.75. 相似文献
149.
Recovery of Yersinia enterocolitica from streams and lakes of California. 总被引:19,自引:10,他引:9 下载免费PDF全文
Stream and lake water from the Mammoth Lakes region of California was sampled for Yersinia enterocolitica. From 10 of the 34 sites examined, organisms were isolated that were biochemically identified as Y. enterocolitica. Only one of the ten strains could be serologically confirmed. This strain was identified as Y. enterocolitica serotype 16. Although an outbreak of enteritis in the area prompted this study, no correlation with gastrointestinal disease could be established since the majority of the strains were untypeable. 相似文献
150.
When 1,N6-ethenoadenosine triphosphate (epsilon-ATP) is free in solution, its fluorescence is collisionally quenched by iodide ion, by methionine, by tryptophan, and by cysteine. None of these quenches the fluorescence of epsilon-ATP bound to G-actin. Thus, the ethenoadenine base is bound in a region of the protein which is inaccessible to collisions with these reagents. Since we have previously shown that the fluorescence of epsilon-ATP is quenched by water, the long lifetime of epsilon-ATP bound to G-actin (36 nsec, vs 27 nsec for epsilon-ATP in water) indicates that the bound nucleotide base is inaccessible to collisional quenching by water molecules. 相似文献