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11.
Plant and Soil - Soil organic matter (SOM) supports multiple soil ecosystem functions, underpinned by processes such as C sequestration, N mineralization, aggregation, promotion of plant health and...  相似文献   
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Over the last two decades, football (soccer) has become a major institution within the popular culture of the Arab-Palestinian citizens of Israel. The centrality of football has given different identity agents opportunities to impose different meanings on the sport, depending on the agents' definitions of collective identity. This article utilizes ethnographic observation in the football stadium and coverage by Arab and Hebrew sports media to illustrate and analyse this battle over meaning. The Hebrew sports media, the Arab sports press, and the Arab audience are three different agents that attach divergent meanings to the notable presence of Arab players in the Israeli football leagues. The article argues that the overlapping interests of the Hebrew sports media on the one hand and the Arab football fans, players, and bureaucrats on the other lead to the construction of the football sphere as an integrative enclave in the general Israeli public sphere. The article considers the relevance of Gramsci's theory of hegemony to explain the production of the integrative meaning of football, and it suggests integrating this explanation with other recent theories regarding the tensions between different discourses of citizenship.  相似文献   
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A study was performed to investigate the effect of weaning at 4 weeks of age on the activity of digestive enzymes in the stomach and pancreatic tissue and in digesta from 3 days prior to weaning to 9 days postweaning in 64 piglets. In stomach tissue the activity of pepsin and gastric lipase was determined. Pepsin activity declined abruptly after weaning but 5 days postweaning the weaning level was regained and in the gastric contents no change in pepsin activity was observed. Weaning did not influence the activity of gastric lipase. The activity of eight enzymes and a cofactor was measured in pancreatic tissue. The effect of weaning on the enzyme activity was highly significant for all enzymes except elastase. The activity of all enzymes remained at the weaning level during day 1–2 postweaning followed by a reduction of the activity. The activity of trypsin, carboxypeptidase A, amylase and lipase exhibited minimum activity 5 days postweaning. Trypsin activity increased to the preweaning level on day 7–9 whereas the activity of the others increased but did not reach the preweaning level. The activity of chymotrypsin, carboxypeptidase B and carboxyl ester hydrolase decreased during the entire experimental period. In digesta no effect of weaning was observed on the activity of amylase and trypsin. The activity of chymotrypsin was reduced after weaning in the proximal third of the small intestine and lipase and carboxyl ester hydrolase activity was reduced in the middle and distal parts of the small intestine after weaning. The present study shows that the activities of the digestive enzymes in the pancreatic tissue are affected by weaning. Even though the pancreatic secretion cannot be judged from these results they show that the enzymes respond differently to weaning. In general the activity of the digestive enzymes in pancreatic tissue is low on day 5 postweaning which in interaction with other factors may increase the risk of developing postweaning diarrhoea.  相似文献   
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Ecosystems - Drought will increasingly threaten forest ecosystems worldwide. Understanding how competition influences tree growth response to drought is essential for forest management aiming at...  相似文献   
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Pre-mRNA processing is an essential mechanism for the generation of mature mRNA and the regulation of gene expression in eukaryotic cells. While defects in pre-mRNA processing have been implicated in a number of diseases their involvement in metabolic pathologies is still unclear. Here, we show that both alternative splicing and alternative polyadenylation, two major steps in pre-mRNA processing, are significantly altered in non-alcoholic fatty liver disease (NAFLD). Moreover, we find that Serine and Arginine Rich Splicing Factor 10 (SRSF10) binding is enriched adjacent to consensus polyadenylation motifs and its expression is significantly decreased in NAFLD, suggesting a role mediating pre-mRNA dysregulation in this condition. Consistently, inactivation of SRSF10 in mouse and human hepatocytes in vitro, and in mouse liver in vivo, was found to dysregulate polyadenylation of key metabolic genes such as peroxisome proliferator-activated receptor alpha (PPARA) and exacerbate diet-induced metabolic dysfunction. Collectively our work implicates dysregulated pre-mRNA polyadenylation in obesity-induced liver disease and uncovers a novel role for SRSF10 in this process.  相似文献   
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To define the link between the early activation defects and the impaired proliferation response of cells from old mice, we characterized the influence of age on expression and activity of proteins that participate in cell-cycle regulation. We found that aging led to significant declines in the ability of mouse CD4(+) T cells to respond to CD3 and CD28 stimuli by induction of the cyclin-dependent kinases CDK2, CDK4, and CDK6, whether the defect was assessed by protein level or functional activity. Induction of CDK2 activity was also impaired in cells from old mice that were activated with PMA plus ionomycin, stimuli that bypass the TCR/CD3 complex, or by CD3/CD28 in the presence of IL-2, indicating that the age-related changes lie, at least in part, downstream of the enzymes activated by these stimuli. We also noted an impairment in the ability of CD4(+) cells from old mice to down-regulate the CDK inhibitor p27 after activation, but we found no change in induction of p21, an inhibitor of CDK that may also play other roles in cell-cycle control. Altered CDK activation is likely to mediate the age-related decline in T cell proliferation to polyclonal stimulation.  相似文献   
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Early systemic treatment of nonobese diabetic mice with high doses of recombinant adeno-associated virus (rAAV) vector expressing murine IL-10 prevents type 1 diabetes. To determine the therapeutic parameters and immunological mechanisms underlying this observation, female nonobese diabetic mice at 4, 8, and 12 wk of age were given a single i.m. injection of rAAV-murine IL-10 (10(4), 10(6), 10(8), and 10(9) infectious units (IU)), rAAV-vector expressing truncated murine IL-10 fragment (10(9) IU), or saline. Transduction with rAAV-IL-10 at 10(9) IU completely prevented diabetes in all animals injected at all time points, including, surprisingly, 12-wk-old animals. Treatment with 10(8) IU provided no protection in the 12-wk-old injected mice, partial prevention in 8-wk-old mice, and full protection in all animals injected at 4 wk of age. All other treatment groups developed diabetes at a similar rate. The rAAV-IL-10 therapy attenuated pancreatic insulitis, decreased MHC II expression on CD11b+ cells, increased the population of CD11b+ cells, and modulated insulin autoantibody production. Interestingly, rAAV-IL-10 therapy dramatically increased the percentage of CD4+CD25+ regulatory T cells. Adoptive transfer studies suggest that rAAV-IL-10 treatment alters the capacity of splenocytes to impart type 1 diabetes in recipient animals. This study indicates the potential for immunomodulatory gene therapy to prevent autoimmune diseases, including type 1 diabetes, and implicates IL-10 as a molecule capable of increasing the percentages of regulatory cells in vivo.  相似文献   
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