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91.
92.
E B de Melo U F Rocha G C Maugê M S de Campos A Dell'Porto 《Arquivos do Instituto Biológico》1977,44(1-2):85-87
The A. A. studied the distribution of nematodes of the genus Ancylostoma (Dubini, 1843) along the digestive tube of 45 dogs. For the collection of the worms they used the method developed by Mello and Campos. The distribution found was: 97,5% in the jejunum, 1,2% in the ileon, 0,7% in the duodenum, 0,3% in the colon, 0,2% in the cecum and 0,1% in the stomach. 相似文献
93.
Pony mares were observed from January to August for incidence of oestrus, duration of oestrus, length of the oestrous cycle and for ovulation and fertility after injection of HCG. From January to 15 May most mares showed oestrus but the duration of oestrus was quite variable and few mares ovulated in response to HCG. From 15 May to 17 August oestrous cycles were more regular and ovulation was induced within 40-50 h by an intramuscular injection of 1500-5000 i.u. HCG. Pregnancy was established by one mating at a fixed time after HCG in 20 of 69 mares. Degenerate eggs were recovered from the oviducts of anoestrous recently ovulated, mated, unmated and pregnant mares. The first polar body was formed before ovulation in 2 eggs and had not formed in 2 recently ovulated eggs flushed from the oviduct. The second polar body formed after sperm penetration 10-12 h after ovulation. After formation of pronuclei, the first cleavage division occurred at 20 h and the second at 32 h after ovulation. Oestrus was inhibited by progesterone administered by vaginal devices but occurred within 1-3 days in 12 of the 20 mares after withdrawal of the devices. 相似文献
94.
Odile Gateau Maria Rocha de Morillo Pierre Louisot Renée Morelis 《生物化学与生物物理学报:生物膜》1980,595(1):157-160
A sialyl transferase activity is found in purified mitochondria. It is not due to residual contamination and this enzymatic system is located in the outer mitochondrial membrane. This proves mitochondrial autonomy in regard to glycoconjugate sialylation. 相似文献
95.
Chi's are genetic elements that stimulate generalized recombination in their locale in phage λ. All Chi's, wherever located on λ's chromosome, act asymmetrically in crosses blocked in DNA replication: (1) They stimulate exchange primarily to their left on the conventional λ map, and (2) the stimulated exchange is frequently nonreciprocal, the recombinant carrying the Chi element being produced less often than the complementary product. 相似文献
96.
The detection of starvation is a major problem in fish husbandry. Too often the discovery of starving animals is not made until pathogenic organisms are about to overcome the weakened animals. A simple test, using a commercial plastic strip with a reagent area that changes colour in the presence of starvation-induced ketones, was applied to this problem in the mullet, Mugil cephalus. The strip identified ketones in the fish skin mucus, and demonstrated its value in detecting starvation in fishes. 相似文献
97.
The results of this study suggest that many malignant tumors contain low levels of fibrinolytic activator activity. Evidence is presented to suggest that this low activity may be due to the presence of an inhibitor of fibrinolysis. The presence or absence of measurable fibrinolytic activator activity, and/or inhibitor in neoplastic growths may enable one to predict the probability of viable metastases to a distant site. 相似文献
98.
This report reviews the management of five pediatric patients with anterior mediastinal teratomas, and presents a discussion of symptoms, signs, and operative management of these lesions. Surgical resection was accomplished in all cases, with three of the five patients surviving. The two who died had malignant teratomas that were treated with adjunctive chemotherapy and X-ray therapy. Age at onset appears to be a significant factor in the prognosis of the disease. 相似文献
99.
Correlations Between Predominant Heterotrophic Bacteria and Physicochemical Water Quality Parameters in Two Canadian Rivers 总被引:2,自引:2,他引:0
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The heterotrophic bacterial populations in two contrasting rivers have been examined over a period of 1 year. The populations were analyzed (i) as total heterotrophic counts, (ii) as species numbers, using numerical taxonomy, (iii) by diversity indices, and (iv) by factor analysis. Isolates were obtained by plating directly from water samples and by chemostat enrichment. Four factors emerged which profiled the bacterial community and were common to both rivers. They were, in order of decreasing importance, fermentative metabolism, inorganic nitrogen metabolism, fluorescence-oxidative metabolism, and lack of starch hydrolysis. Several factors produced significant correlations with a range of physicochemical parameters, which were also measured. The correlations suggested an intricate algal-bacterial interaction. The oxidative metabolism factor correlated with rainfall in one river, suggesting that the oxidative bacteria may be washed in from the surrounding land. In the other river, the oxidative-fermentative factor correlated negatively with sunshine. Factor analysis was the most effective method for revealing correlations between bacterial characteristics and the environmental parameters; however, the use of a variety of methods provided more insight into the ecological aspects. 相似文献
100.
A simple double-isotope procedure has been developed for making simultaneous measurements of bound Ca2+ and relative force in glycerinated rabbit psoas bundles containing two fibers. With this preparation it is possible to study Ca2+-troponin interactions coincident with MgATP-induced force development. Over the free [Ca2+] range 6 · 10?8–1.2 · 10?5 M the bound Ca2+ varied from 0.25 to 1.65 μmol/g protein. The free [Ca2+] at half-maximal Ca2+ saturation was 2 · 10?7 M while that a half-maximal force was 5 · 10?7 M. Half-maximal Ca2+ saturation was associated with 20% maximal force. The force-[Ca2+] saturation curve showed a steep rise in slope at greater than half saturation. The observed relationship was consistent with a model in which multiple occupancy of troponin Ca2+-binding sites is essential for initiation of cross-bridge cycling. 相似文献