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51.
Experimental clostridial myonecrosis closely resembling gas gangrene was produced in goats by the intramuscular injection of washed clostridia suspended in adrenalin. The preparation provides a model for the study of clostridial myonecrosis that is relatively isolated from preceding trauma. A new test for the demonstration of clostridial exotoxins, the hemolysin indicator plate test, was described. This test gave reliable results within 6 hr, and only minute quantities of test material were required. Application of this test to would exudates of goats with experimental clostridial myonecrosis demonstrated the presence of the gamma toxin of Clostridium novyi, alpha toxin of C. septicum, and the alpha toxin of C. perfringens in exudates from animals injected with washed Clostridium bacilli suspended in adrenalin. Exudates from goats injected with C. perfringens were lethal for mice and produced necrosis of guinea pig skin typical of C. perfringens. The convincing demonstration of clostridial exotoxins formed in vivo in this experimental model could be the basis for definition of clostridial exotoxin actions which have evaded study in the past. 相似文献
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Three oligodeoxynucleotides have been chemically synthesized and used as hybridization probes to detect gastrin-specific mRNA within an heterogeneous population of RNA molecules. Using these oligonucleotides whose nucleotide sequences were deduced from the amino acid sequence of the hormone, 0.2 fmol of gastrin mRNA can be detected/microgram of poly(A)-RNA from hog antrums. The 32P-labeled oligonucleotides hybridize specifically to RNA covalently coupled to DBM-paper (Alwine, J.C., Kemp, D.J., and Stark, G.R. (1977) Proc. Natl. Acad. Sci. U.S.A. 74, 5350-5354). Labeled oligonucleotides also hybridize specifically to RNA separated by gel electrophoresis in the presence of CH3HgOH and covalently coupled to DBM-paper. Using this procedure, we have found that the mRNA coding for gastrin contains about 620 nucleotides, which is in agreement with results obtained using gastrin cDNA to determine mRNA size. 相似文献
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John Donahoe Inge Noyes George E. Milo Steven E. Weisbrode 《In vitro cellular & developmental biology. Plant》1982,18(5):429-434
Summary Human foreskin fibroblasts transformed by representative chemicals from five different classes of chemical carcinogens, some
requiring enzymatic activation and direct acting carcinogens, produced cell populations that exhibited anchorage-independent
growth and expression of neoplastic potential in either nude mice or chick-embryonic skin (CES). There is a high degree of
correlation between tumor incidence and invasiveness of CES. The unique feature of CES is the rapidity of expression of cellular
neoplasia and interpretation of the simulated tumor in 4 d as a simulated fibrosarcoma. This method represents a system that
can be used to evaluate human carcinogens in vitro in 6 to 10 wk.
This work was supported in part by AFSOR, F49620-80 and the National Cancer Institute, Bethesda, MD, R01-CA-25907. 相似文献
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Gal Eyal J?rg Wiedenmann Mila Grinblat Cecilia D’Angelo Esti Kramarsky-Winter Tali Treibitz Or Ben-Zvi Yonathan Shaked Tyler B. Smith Saki Harii Vianney Denis Tim Noyes Raz Tamir Yossi Loya 《PloS one》2015,10(6)
The phenomenon of coral fluorescence in mesophotic reefs, although well described for shallow waters, remains largely unstudied. We found that representatives of many scleractinian species are brightly fluorescent at depths of 50–60 m at the Interuniversity Institute for Marine Sciences (IUI) reef in Eilat, Israel. Some of these fluorescent species have distribution maxima at mesophotic depths (40–100 m). Several individuals from these depths displayed yellow or orange-red fluorescence, the latter being essentially absent in corals from the shallowest parts of this reef. We demonstrate experimentally that in some cases the production of fluorescent pigments is independent of the exposure to light; while in others, the fluorescence signature is altered or lost when the animals are kept in darkness. Furthermore, we show that green-to-red photoconversion of fluorescent pigments mediated by short-wavelength light can occur also at depths where ultraviolet wavelengths are absent from the underwater light field. Intraspecific colour polymorphisms regarding the colour of the tissue fluorescence, common among shallow water corals, were also observed for mesophotic species. Our results suggest that fluorescent pigments in mesophotic reefs fulfil a distinct biological function and offer promising application potential for coral-reef monitoring and biomedical imaging. 相似文献
56.
Noyes FR Barber-Westin SD Smith ST Campbell T 《Journal of strength and conditioning research / National Strength & Conditioning Association》2011,25(8):2151-2160
The purpose of this study was to determine if a sports-specific training program could improve neuromuscular indices in female high school volleyball players. We combined components from a previously published knee ligament injury prevention intervention program for jump and strength training with additional exercises and drills to improve speed, agility, overall strength, and aerobic conditioning. We hypothesized that this sports-specific training program would lead to significant improvements in neuromuscular indices in high school female volleyball players. Thirty-four athletes (age 14.5 years ± 1.0) participated in the supervised 6-week program, 3 d·wk(-1) for approximately 90-120 minutes per session. The program was conducted on the school's volleyball court and weight room facilities. The athletes underwent a video drop-jump test, multistage fitness test, vertical jump test, and sit-up test before and after training. A significant increase was found in the mean VO2max score (p < 0.001), where 73% of the athletes improved this score. A significant improvement was found in the sit-up test (p = 0.03) and in the vertical jump test (p = 0.05), where 68% of the athletes increased their scores. In the drop-jump video test, significant increases were found in both the mean absolute knee separation distance (p = 0.002) and in the mean normalized knee separation distance (p = 0.04), indicating improved lower limb alignment on landing. No athlete sustained an injury or developed an overuse syndrome during training. This program significantly improved lower limb alignment on a drop-jump test, abdominal strength, estimated maximal aerobic power, and vertical jump height and may be implemented in high school female volleyball programs. 相似文献
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Abstract. One invalid lectotype designation proposed in a recent revision of European species of Copidosoma is validated ( Encyrtus geniculatus Dalman) and four incorrectly cited designations are corrected ( C. peninsulare Mercet, E. filicornis Dalman, E. flagellaris Dalman, E. machaeras Walker). One species, C. tremblayi , is described as new. 相似文献