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The aim of the present investigation was to study the effect of calcium ionophore activation on blastocyst production following intracytoplasmic sperm injection (ICSI) in in vitro‐matured Caprine oocytes. A total of 470 in vitro‐matured oocytes were selected and randomly divided in to three groups. Cumulus oocyte complexes (COCs) recovered by slicing the Caprine ovaries were matured in TCM199 supplemented with 10% foetal bovine serum (FBS) + 10% follicular fluid + FSH (5 μg/ml) + LH (10 μg/ml) + estradiol (1 μg/ml) + EGF (10 ng/ml) + BSA (3 mg/ml) for 27 h in humidified atmosphere at 38.5°C with 5% CO2 in CO2 incubator. After 27 h of culture, selected COCs (n = 470) were separated from cumulus cells by treating with 0.1% hyaluronidase enzyme and passing repeatedly through a fine pipette and randomly divided into three groups. In group 1, (n = 168) matured oocytes were injected with injection micropipette without sperm as control. In group 2, (n = 152) capacitated spermatozoa were injected into cytoplasm of in vitro‐matured oocytes through injection micropipette. In group 3, (n = 150) capacitated spermatozoa were injected into cytoplasm of in vitro‐matured oocytes through injection micropipette and then activated with 5 μm Ca ionophore for 5 min. The oocytes of all groups were then culture in RVCL media for embryo development. The cleavage rate was observed after 48–72 h of injection. The cleavage rate and blastocyst production in group 1, 2 and 3 were 0.00 and 0.00, 18.42 and 3.57 and 61.33% and 16.30%, respectively. The result indicated that mechanical activation failed to induce cleavage in in vitro‐matured Caprine oocytes, whereas chemical activation of intracytoplasmic sperm‐injected in vitro‐matured Caprine oocytes showed significantly higher cleavage rate and blastocyst production as compare to non‐activated oocytes.  相似文献   
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Thioglycolic acid neutralized with sodium carbonate, sodium thioglycolate (Eastman), ethyl mercaptan, cysteine hydrochloride and certain sulfur-containing reducing agents (sodium bisulfite and sodium hydrosulfite) antagonize the antibacterial action of 2-methyl-1,4-naphthoquinone on Escherichia coli in a synthetic medium. Other reducing agents such as stannous chloride, potassium formate and sodium thiosulfate, show no such antagonism. The antibacterial activities of 2-methyl-3-chloro-1,4-naphthoquinone and 2,6-dimethyl-1,4-naphthoquinone are also abolished by excess thioglycolate and cysteine, while that of 2-methyl-3-methoxy-1,4-naphthoquinone with -OCH(3) instead of -Cl or -H in the 3 position on the quinone ring, is not. These findings suggest that the mode of antibacterial action of 2-methyl-1,4-naphthoquinone is by blocking essential enzymes through combination with sulfhydryl groups, or through combination with sulfhydryl groups of essential bacterial metabolites. This combination may take place in the 3-position on the quinone ring. This mode of action is similar to that suggested by other investigators for several antibiotic agents including penicillin. The antibacterial activity of the methoxy quinone, however, even in the presence of sulfhydryl groups, suggests that the foregoing explanation may not be the complete one.  相似文献   
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The aim of this study was to evaluate the viability in the effect of open pulled straw (OPS) vitrification procedure of sheep embryos after direct transference. Embryos were produced in vivo and cryopreserved in slow freezing or OPS vitrification. The survival rates of cryopreserved embryos were compared to non-frozen standard pattern. In a first set of experiments, embryos at morula and blastocyst stages were dived in ethylene glycol (1.5 M) and frozen in an automatic freezer. After being thawed, they were directly or indirectly transferred to ewes recipient. A second group of embryos were drawn into OPS and plunged into liquid nitrogen after being exposed at room temperature for 1 min and 45 s in 10% EG plus 10% dimethyl sulphoxide (DMSO), then again for 30 s in 20% EG + 20% DMSO + 0.5 M sucrose. After being warmed, embryos were also directly transferred using a French mini straw as the catheter for the transplantation process or after in vitro dilution of cryoprotectants (two-step-process). No significant difference was observed among fresh, frozen or vitrified embryos on pregnancy rate (50.0%, 38.6% and 55.8%). However, when we evaluated only the direct transference, the pregnancy rate of OPS vitrified embryos was higher than that of frozen embryos (57.1% vs 34.8%) (p = 0.07). In addition, vitrified morulae had a higher pregnancy rate than the one with frozen embryos (64.0% vs 38.9%) (p = 0.07). Finally, our results indicate that OPS vitrification technique in association with direct transference improves the viability of sheep embryos with potential applications to field conditions.  相似文献   
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In vitro assays for allergen specific immunoglobulin E (IgE) are a convenient and reproducible alternative to intradermal skin testing in dogs. Such tests may be used to support a diagnosis of atopic dermatitis and to define appropriate allergens for immunotherapy. Current in vitro assays rely upon monoclonal or polyclonal antibodies as IgE detection reagents. However, in sera where allergen-specific IgG occurs in great excess, any IgE:IgG cross-reactivity of the detection reagent may result in lowered assay specificity. Therefore, we have developed an assay for canine IgE which uses a recombinant form of the extracellular part of the alpha chain of the human high affinity IgE receptor (FcvarepsilonRIalpha). Biotinylated FcvarepsilonRIalpha shows no significant binding to purified canine IgG, and recognizes a heat labile antibody in serum, with a detection limit of 73-146pg/ml. Comparison of assay signals using the labeled FcvarepsilonRIalpha and a highly specific anti-canine IgE monoclonal antibody (MAb) shows good agreement. The FcvarepsilonRIalpha is therefore a sensitive and specific alternative to polyclonal or monoclonal antibodies for canine serum IgE measurement.  相似文献   
108.
IQ's between 3 and 18 years of age were used to predict attained education and occupational status after 26 years of age. By the second grade these predictive correlations approached those that have been obtained with contemporaneous adult IQ's, especially for occupational status. However, they were not high enough for practical purposes requiring long-term prediction for individual normal children.  相似文献   
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Collateral pulmonary circulation was evaluated angiographically 11 months after experimental infection of dogs with either 25 or 100 infective larvae of Dirofilaria immitis. In both groups, collateral pulmonary circulation developed from bronchial arteries and esophageal branches of the left gastric artery. Of the four dogs receiving 25 larvae, one had no detectable collateral circulation, one developed collateral pulmonary circulation from the bronchial arteries only, and two had collateral pulmonary circulation from the bronchial arteries and esophageal branches of the left gastric artery. Of the three dogs receiving 100 larvae, all had collateral pulmonary circulation from the bronchial arteries and the esophageal branches of the left gastric artery. Bronchial artery collateral pulmonary circulation was more extensive in the 100-larvae dogs than in the 25-larvae dogs. Collateral pulmonary circulation from the left gastric artery esophageal branches was similar in both dog groups. Angiographically detectable collateral pulmonary circulation developed within the first year of heaertworm infection. In some respects, the extent of collateral pulmonary circulation development was related to the severity of heartworm infection.  相似文献   
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