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71.

The objectives of this study are to determine the spatial and temporal land use/cover changes in a semi-arid agricultural basin (Develi Basin) after the implementation of an irrigation project and to understand how these changes affected the wetlands (Sultan Marshes) located in the basin. The changes were determined using multitemporal Landsat Thematic Mapper and Landsat 8 Operational Land Imager imagery taken in 1987, 1998, 2007, and 2013. The images were classified into six information classes (grasslands/shrublands, croplands, permanent wetlands, water bodies, barren, and urban/built-up) using a hybrid classification method. Post-classification change detection was applied to determine the changes between different years. Overall, the accuracy of the classified images ranged from 85 to 94%. Grasslands/shrublands covered the largest area in the basin (63% in 2013), followed by croplands (32% in 2013). The area covered by water bodies, permanent wetlands, barren, and urban/built-up was 5% (in 2013). From 1987 to 2013, croplands expanded by 56%, while grasslands/shrublands declined by 15%. The areas occupied by water bodies decreased by 88% and permanent wetlands decreased by 4%. Urban/built-up areas expanded by 140%. The hydrologic regime of the Sultan Marshes wetland changed, which resulted in declines in water volumes by 85% and in water inflows by 55% from 2000 to 2015. Climatic variations during the 1987–2013 period were low and there was no apparent trend in precipitation and air temperature, which ruled out climatic conditions as one of the drivers of wetland changes. Economic and institutional factors supported the expansion of irrigated agriculture and animal husbandry in the basin and accelerated the expansion of croplands and conversion to industrial and fodder crops and orchards from traditional non-irrigated crops. Expansion of croplands and irrigated agriculture were the major drivers of the changes in the Sultan Marshes.

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72.
Cardiovascular diseases are the main reason of high mortality among hemodialysis patients. Decreased serum selenium levels may have a role in accelerated atherosclerosis in this patient group. The hypothesis of this study was to show a correlation between decreased serum selenium levels and coronary flow reserve as an indicator of endothelial dysfunction and atherosclerosis in HD patients. Seventy-one chronic hemodialysis patients and age 65 and sex-matched healthy controls were included in the study. Plasma selenium levels were measured by spectrophotometry, and coronary flow reserve was assessed by transthoracic Doppler echocardiography. Serum selenium levels (34.16?±?6.15 ng/ml vs. 52.4?±?5.51 ng/ml, P?<?0.001) and coronary flow reserve values (1.73?±?0.11 vs. 2.32?±?0.28, P?<?0.001) were significantly lower in hemodialysis patients compared with controls, respectively. There was a significant positive correlation between coronary flow reserve and serum levels of selenium (r?=?0.676, P?<?0.001). A linear regression analysis showed that serum levels of selenium were independently and positively correlated with coronary flow reserve (regression coefficient?=?0.650, P?<?0.05). This study was the first to show a positive and independent correlation between decreased selenium levels and diminished coronary flow reserve as an indicator of endothelial dysfunction and atherosclerosis in hemodialysis patients. Our data suggest that decreased serum selenium levels may facilitate the development of endothelial dysfunction and disruption of coronary flow reserve which occur before the development of overt atherosclerosis.  相似文献   
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74.
B cells were first discovered as antibody producing cells, as B-1 B cells and finally as effector cells. In recent years their capacity to serve as antigen presenting cells is increasingly appreciated, and better tools are needed to study their function. We have previously described a new mouse model, the iDTR mice, that allow for the Cre-mediated expression of the diphtheria toxin receptor, thus rendering cells that express the Cre-recombinase sensitivity to diphtheria toxin. Herein we describe a new mouse line, the B-DTR mice, where the CD19-Cre was crossed to the iDTR mice. B-DTR allows for the efficient and cost-effective depletion of different B cell subpopulations, but only partially plasma cells. These mice can therefore be used to study the importance of B cells versus plasma cells in different immune responses and autoimmune diseases.  相似文献   
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An artificial neural network (ANN) model was developed for simulating water levels at the Sultan Marshes in Turkey. Sultan Marshes is a closed basin wetland located in the semi-arid Central Anatolia region of Turkey. It is one of the thirteen Ramsar sites of Turkey and a national park. Water levels at the Sultan Marshes showed strong fluctuations in recent decades due to the changes in climatic and hydrologic conditions. In this study, monthly average water levels were simulated using a multi-layer perceptron type ANN model. The model inputs consisted of climatic data (precipitation, air temperature, evapotranspiration) and hydrologic data (ground water levels, spring flow rates, and previous month water levels) available from 1993 to 2002. 70 % of the data were used for model training and remaining 30 % were used for model testing. Model training was accomplished by using a scaled conjugate gradient backpropagation algorithm. The performance of the model was evaluated by calculating the root mean square error (RMSE) and the coefficient of determination (R 2) between observed and simulated water levels. The sensitivity of the model to input parameters was determined by evaluating the model performance when a single input variable was excluded. It was found that the ANN model can successfully be used for simulating water levels at the Sultan Marshes. The model developed using all input variables provided the best results with two neurons in the hidden layer. The RMSE and R 2 of the simulated water levels were 4.0 cm and 96 %, respectively. The sensitivity analysis showed that the model was most sensitive to previous month water levels and ground water levels.  相似文献   
77.
Tuna  Esin  Ersoy  Yeliz Emine  Bulut  Pelin  Ozdemir  Filiz  Buyru  Nur 《Molecular biology reports》2020,47(3):1605-1612
Molecular Biology Reports - Breast cancer, which is the most common type of cancer among women, is a heterogenous disease. It results from progressive accumulation of genetic and epigenetic...  相似文献   
78.
In this study, seed germination percentages, effects on phases of mitosis and α-amylase enzyme activity of lentil seeds treated with four different concentrations (0.25, 0.5, 1 and 1.5%) of Fusilade (Fluazifop-p-butyl) were determined. Median EC (effective concentration) values were calculated according to seed germination percentages after treatment for 72 h. Germination percentages of primary lentil roots decreased with increasing Fusilade concentrations. Cytological observations showed that the mitotic frequency in root meristematic cells were decreased parallel to the increase in concentrations and all Fusilade concentrations applied decreased the activity of α-amylase enzyme in lentil seeds. The obtained results indicate that the herbicide Fusilade had the ability to cause reduction in seed germination, mitotic frequency and also α-amylase activity of lentil seeds.  相似文献   
79.
This study was designed to examine the effects of vitamin E on the levels of Zn, Mn, Cu, Fe, and carbonic anhydrase in rats with bleomycin-induced pulmonary fibrosis. Twenty-one male Wistar albino rats were randomly divided into three groups: bleomycin alone, bleomycin+vitamin E, and saline alone (control group). The bleomycin group was given 7.5 mg/kg body weight (single dose) bleomycin hydrochloride intratracheally. The bleomycin+vitamin E group was also instilled with bleomycin hydrochloride but received injections of α-tocopherol twice a week. The control group was treated with saline alone. Animals were sacrified 14 d after intratracheal instillation of bleomycin. Tissue Zn, Mn, Cu, Fe, and carbonic anhydrase activities were measured in the lung and liver. Lung Cu, Fe, and carbonic anhydrase activity increase in both experimental groups. Zn and Mn levels decreased, except for the Mn level in the bleomycin group. Liver Zn, Mn, and Cu levels decreased in both experimental groups compared to the control group, whereas Fe and carbonic anhydrase activity increased in comparison to the control group. However, the liver tissue Fe level decreased compared to the control group. In the histopathologic assesment of lung sections in the bleomycin+vitamin E group, partial fibrotic lesions were observed, but the histopathologic changes were much less severe compared to the bleomycin-treated group.  相似文献   
80.
The present study was designed to see if acute local inhibition of Ras-GTPase before or after ischemia (during perfusion) would produce protection against ischemia and reperfusion (I/R)-induced cardiac dysfunction. The effect of glibenclamide, an inhibitor of cardiac mitochondrial ATP-sensitive potassium (mitoK(ATP)) channels, on Ras-GTPase-mediated cardioprotection was also studied. A 40 min episode of global ischemia followed by a 30 min reperfusion in perfused rat hearts produced significantly impaired cardiac function, measured as left ventricular developed pressure (P(max)) and left ventricular end-diastolic pressure (LVEDP). Perfusion with Ras-GTPase inhibitor FPT III before I/R [FPT(pre)], significantly enhanced cardiac recovery in terms of left ventricular contractility. P(max) was significantly higher at the end of 30 min reperfusion in FPT(pre)-treated hearts compared to pre-conditioned hearts. However, the degree of improvement in left ventricular contractility was significantly less when FPT III was given only after ischemia during reperfusion [FPT(post)]. Combination treatment with FPT III and glibenclamide before I/R resulted in significant reduction of FPT III-mediated cardioprotection. These data suggest that activation of Ras-GTPase signaling pathways during ischemia are critical in the development of left ventricular dysfunction and that opening of mitoK(ATP) channels, at least in part, contributes to cardioprotection produced by Ras-GTPase inhibition.  相似文献   
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