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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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Agriculture is the major consumer of water and it is possible to decrease water consumption in this sector by proper irrigation scheduling. Irrigation scheduling is based on crop water requirements. Saffron is an important crop in Iran. The main purpose of this study was to determine the potential evapotranspiration and crop coefficient for saffron using single and dual crop coefficients, in Badjgah region, College of Agriculture, Shiraz University, Shiraz, Iran. Three water-balance lysimeters were used for this experiment in a two-year study. Total saffron potential evapotranspiration values were 523 and 640 mm in the first and second growing seasons, respectively. The maximum evapotranspiration rates for saffron were 4.5 and 6.1 mm d?1 in the first and second growing seasons, respectively. Based on the results of this study, different saffron growing stages for evapotranspiration were 30, 40, 70 and 60 days. Crop coefficient (K c) values for the initial, mid- and late-season growth stages were 0.41–0.45, 0.93–1.05 and 0.29–0.31 in both years, respectively. Basal crop coefficient (K cb) values for the initial, mid- and late-season growth stages were 0.15–0.16, 0.41–0.65 and 0.15–0.17 in both years, respectively.  相似文献   
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Better irrigation and nitrogen (N) scheduling and more efficient management of crop production require modeling of plant growth and crop yield. Models become more applicable if they are simple and require less and accessible inputs. The objective of this study was to use simple equations of soil water budget, evapotranspiration (ET), leaf area index (LAI), yield, and harvest index (HI)–transpiration function to develop a model for the prediction of growth and yield of maize under various water and N rates. The model was calibrated based on given data under sprinkler irrigation and verified based on independent data under furrow irrigation. The comparison between predicted and measured values of different crop parameters did not show any significant difference and the model was able to estimate LAI, ET, soil water content, HI, dry matter, and grain yield properly. Furthermore, an equation was presented to predict daily dry matter accumulation by a logistic curve for different water and N applications. It was concluded that the presented simple model was able to predict crop yield quite well and hence could be used for farm irrigation and N scheduling and management of both. Furthermore, the relationship between LAI and ET may be different in various environmental conditions that should be considered in using the model.  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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Improved evapotranspiration estimation is instrumental in annual potential recharge (Re) evaluations of semi-arid regions, in the context of the water balance approach. Complementary relationship areal evapotranspiration (CRAE) and advection–aridity (AA) and a general combination equation proposed by Granger and Gray (GG) were evaluated for the estimation of actual evaporation (Ea) from bare soil under occurrence of Re. Model capability was evaluated by utilizing data from lysimeter measurements during the hydrological years [(2011–2012) and (2012–2013)]. Measured parameters included soil moisture (SM), rainfall and related meteorological data and Re (lysimeter output). All models with original parameters performed poorly during 2011–2012 and 2012–2013, underestimating annual Re values. The 2011–2012 data were used for model calibration, considering annual Ea [criterion (I)] and cumulative Ea during the occurrence period of Re [criterion(II)]. The calibrated CRAE model [criterion (II)] produced the best simulation for Ea (NRMSE < 30%). The 2012–2013 data were used to validate the models, and the calibrated CRAE model produced acceptable results (NRMSE < 10%) in SM simulation (both criteria). But calibrated CRAE under criterion (II) provided the best estimation of annual Re (ΔQ < 6%). According to the results, CR models can produce acceptable estimation of annual Re, if initially calibrated utilizing criterion (II).  相似文献   
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