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Background: In this study, we evaluated the incidence of apoptosis at the ultrastructural levels and expression of some apoptosis-related genes in vitrified human ovarian tissue just after warming. Methods: Human ovarian tissue biopsies from 23 women after caesarean section were transported to the laboratory within 2 hours, and then they were cut into small pieces. Some pieces were vitrified and warmed and the other samples were considered as control. Apoptosis was assessed by a transmission electron microscope and also by molecular analysis of pro-apoptotic (Fas, FasL, Bax, p53, caspase8, and caspase3) and antiapoptotic (Bcl-2 and BIRC5) genem RNA levels using real-time RT-PCR before and after vitrification. Results: No sign of apoptosis was shown ultrastructurally in vitrified samples. The level of FasL, Bcl-2, Bax, p53, and caspase3 mRNA and Bax:Bcl-2 ratio were similar in non-vitrified and vitrified groups; however, the expression of Fas and caspase8 genes was higher and BIRC5 was lower in vitrified samples compared to non-vitrified group (P<0.05). Conclusion: The fine structure of human vitrified ovarian tissue was well preserved; moreover, vitrification was shown to affect the expression of some apoptosis-related genes. However, additional study is needed to confirm this observation.Key Words: Vitrification, Apoptosis, Gene expression, Ovary, Humans  相似文献   
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The plasma desorption mass spectrometry method is used to determine the molecular weights of larger molecules than before, to determine the molecular weights of proteins and peptides in mixtures, and to monitor protein modification reactions. Proteins up to molecular weight 25,000 can now be studied with a mass spectrometric technique. Protein-peptide mixtures that could not be resolved with conventional techniques were successfully analyzed by this technique. The precision of the method is good enough to permit one to follow the different steps in the conversion of porcine insulin to human insulin.  相似文献   
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Simulation of crop yield allows better planning and efficient management under different environmental inputs such as water and nitrogen application. However, most of the models are complicated and difficult to understand. Furthermore, input data are not readily available. The objectives of this investigation were to use logistic equation to quantify the influence of seasonal water and nitrogen application on maize biomass accumulation and grain yield and to develop empirical models for prediction of maize biomass and grain yield. Logistic equations were fitted to dray matter (DM) yield at different times in the growing season at different irrigation water and nitrogen levels. The parameters of the logistic equations were then fitted to irrigation water and nitrogen as empirical functions. Further, the harvest index (HI) was related to the applied water and nitrogen as another empirical model. The empirical logistic models were used to estimate the DM and grain yield based on data from another experiment in the same area. Results indicated that the empirical models predicted the DM yield during the growing season with an acceptable accuracy, but dry matter (DM) prediction at harvest was very good. The grain yield also was predicted with a very good accuracy. It is concluded that logistic equation along with the presented empirical models for prediction of constants in logistic equation and HI are appropriate for accurate prediction of DM and grain yield of maize at the study region.  相似文献   
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The study was conducted using a completely randomized design with five treatments each with three replicates. In each treatment, 30 fish (10 per replicate) with an average body weight of 30 ± 0.6 g were randomly allocated to 60‐L tanks. Treatments consisted of a control (a diet without rutin and oxytetracycline (OTC)), an OTC treatment (a diet free from rutin and containing 75 mg kg?1 body weight OTC) and the (OTC + rutin) treatments including diets with different levels of rutin, 500 (R‐500 + OTC), 1000 (R‐1000 + OTC) and 2000 (R‐2000 + OTC) ppm and 75 mg kg?1 body weight per day OTC which were fed to fish for 28 days. The aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities in the blood serum after the OTC treatment were significantly (P < 0.05) higher than in the control. After the three (OTC+rutin) treatments, the AST and ALT activities were not significantly different from the control. The level of glucose in the blood serum was significantly lower (P < 0.05) in all treatments as compared to the OTC treatment. Superoxide dismutase (SOD) and catalase (CAT) activities in red erythrocyte lysates were significantly (P < 0.05) reduced after OTC treatment in comparison with the control. After the three (OTC+rutin) treatments, the values of these indices were significantly (P < 0.05) higher than the OTC treatment, in particular for the R‐1000 + OTC treatment. It seems that rutin, as a non‐enzymatic inhibitor, is capable of preventing damage to the liver tissue and reducing oxidative stress.  相似文献   
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Background: Tay-Sachs disease (TSD), or GM2 gangliosidosis, is a lethal autosomal recessive neurodegenerative disorder, which is caused by a deficiency of beta-hexosaminidase A (HEXA), resulting in lysosomal accumulation of GM2 ganglioside. The aim of this study was to identify the TSD-causing mutations in an Iranian population. Methods: In this study, we examined 31 patients for TSD-causing mutations using PCR, followed by restriction enzyme digestion. Results: Molecular genetics analysis of DNA from 23 patients of TSD revealed mutations that has been previously reported, including four-base duplications c.1274_1277dupTATC in exon 11 and IVS2+1G>A, deletion TTAGGCAAGGGC in exon 10 as well as a few novel mutations, including C331G, which altered Gln>Glu in HEXB, A>G, T>C, and p.R510X in exon 14, which predicted a termination codon or nonsense mutation. Conclusion: In conclusion, with the discovery of these novel mutations, the genotypic spectrum of Iranian patients with TSD disease has been extended and could facilitate definition of disease-related mutations. Key Words: Tay-Sachs disease, β- hexosaminidase A, β- hexosaminidase B  相似文献   
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