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991.
New therapy strategies for the treatment of cancer are rapidly emerging because of recent technology advances in genetics and molecular biology. Although newer targeted therapies can improve survival without measurable changes in tumor size, clinical trial conduct has remained nearly unchanged. When potentially efficacious therapies are tested, current clinical trial design and analysis methods may not be suitable for detecting therapeutic effects. We propose an exact method with respect to testing cytostatic cancer treatment using correlated bivariate binomial random variables to simultaneously assess two primary outcomes. The method is easy to implement. It does not increase the sample size over that of the univariate exact test and in most cases reduces the sample size required. Sample size calculations are provided for selected designs.  相似文献   
992.
Sensitivities to recombinant human tumor necrosis factor- (TNF-) and chemotherapeutic agents (cisplatin, peplomycin, methotrexate) were evaluated in 20 tumor cells of head and neck squamous cell carcinomas, using a dye uptake method. Also, numbers of TNF receptors of these tumor cells were measured by Scatchard plot analysis. There was no relationship between the number of TNF- receptors and the sensitivity to TNF-. Furthermore, there was no correlation between the sensitivity to TNF- and that to chemotherapeutic drugs, nor between the sensitivity to TNF- and the clinical response to chemotherapy including of cisplatin and peplomycin. The sensitivity to TNF- was higher in poorly differentiated carcinomas than in well differentiated ones.Abbreviations BSA Bovine serum albumin - CDDP Cisplatin - 5-Fu 5-fluorouracil - IC50 Inhibition concentration 50 - MTX Methotrexate - PLM Peplomycin - TNF- Tumor necrosis factor-  相似文献   
993.
994.
In the present study, we have described and compared both the number and the types of the mistakes that were made during reading of the Ishihara plates by 3,926 students attending the secondary schools in the province of Cosenza (Calabria, Southern Italy) and by 546 Calabrian university students all without colour-blindness. There were no qualitative differences in the types of mistakes made by the two groups of subjects during their reading of the Ishihara plates. Moreover, we have reported both the mean frequencies and types of colour-blindness in only the province of Cosenza. During this study, it was shown that the ishihara test is reliable during screenings for the diagnosis of colour vision deficiencies, as shown by some previous investigations.  相似文献   
995.
The cross-pollinated crop Brassica oleracea var. capitata L. shows good heterotic heterosis at high output; better standing of the plants; early maturity; larger and more homogeneous heads; consistency of head compactness; and disease-tolerance in F1 hybrids. There is very limited information documented on the epistasis of essential cabbage characters. We expand the research in this study to include an upgraded test to cross-design for enrolling and estimating epistasis and other genetic variance components controlling head yield and component traits in cabbage. The data was obtained from 45 families produced by crossing 15 lines with three testers; SC 2008–09, E-1-3-1&2, and their single cross F1, was subjected to triple test cross analysis. The current study results confirmed “j + 1” form of epistasis which is a major component for all traits. The plant spread, non-wrapper leaves, nethead/grossweight, polar/equatorial diameter, marketable head yield per plot, iron content and dry matter lugged both “j + 1” and 'i' type with the predominance of the 'i' type of interaction. Except for head shape index, equatorial diameter, head compactness was more noticeable when observed in dominance component. The degree of dominance is in the partial range, but both the head shape index/compactness and equatorial diameter showed over dominance. For maximum part, superiority was shown in both the directions. Appropriate breeding procedures are proposed to exploit the different forms of gene effects discovered for genetic improvement of head yield and quality traits.  相似文献   
996.
We present a survey of sample size formulas derived in other papers for pairwise comparisons of k treatments and for comparisons of k treatments with a control. We consider the calculation of sample sizes with preassigned per‐pair, any‐pair and all‐pairs power for tests that control either the comparisonwise or the experimentwise type I error rate. A comparison exhibits interesting similarities between the parametric, nonparametric and binomial case.  相似文献   
997.
The efficiency index (Effindex) combines internal and external loads, and it has been considered a promising tool to evaluate physical fitness status. However, its real applicability and limitations have not been elucidated yet. To examine and discuss the findings from studies that used Effindex as a tool for the evaluation of physical fitness status in team sports. A systematic search was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The databases conferred were PubMed, Scopus, Web of Science, SPORTDiscus, MEDLINE and CINAHL. The articles selected were published up to March 2021. Fourteen articles were included after meeting the inclusion criteria. A wide variety of combinations of external and internal loading parameters to calculate Effindex were found. The pooled sample included 349 male participants (23 ± 3 years). Fifty-nine percent of the sample were soccer players, 20% rugby players, 10% Australian football players, 7% hurling players, and 4% basketball players. Most Effindex calculations used total distance (TD) divided by heart rate derived parameters. However, recent studies have suggested the use of accelerations as the external load parameter. Effindex is a simple and powerful tool for the evaluation of physical fitness status in team sports athletes. The disparity of external and internal loading parameters used to calculate Effindex may affect its sensitivity to detect changes in fitness status in different team sport settings. More studies with indoor team sports and female athletes are warranted.  相似文献   
998.
目的 研究金诺芬对表皮葡萄球菌及其生物膜的作用。方法 利用微量稀释法药敏试验检测金诺芬对表皮葡萄球菌浮游菌生长的影响,并利用结晶紫染色和激光共聚焦显微镜观察金诺芬对表皮葡萄球菌生物膜形成的影响。结果 金诺芬对表皮葡萄球菌的MIC和MBC分别为0.125~0.250 μg/mL和2.000~4.000 μg/mL。同时,4 μg/mL金诺芬还能显著抑制表皮葡萄球菌标准菌株和临床菌株生物膜的形成(P<0.05)。通过激光共聚焦显微镜观察发现金诺芬能有效抑制生物膜的形成,降低生物膜的聚集,并增加死亡细菌的比例。结论 金诺芬能显著抑制表皮葡萄球菌浮游菌的增殖和生物膜的形成。  相似文献   
999.
The identification of population bottlenecks is critical in conservation because populations that have experienced significant reductions in abundance are subject to a variety of genetic and demographic processes that can hasten extinction. Genetic bottleneck tests constitute an appealing and popular approach for determining if a population decline has occurred because they only require sampling at a single point in time, yet reflect demographic history over multiple generations. However, a review of the published literature indicates that, as typically applied, microsatellite-based bottleneck tests often do not detect bottlenecks in vertebrate populations known to have experienced declines. This observation was supported by simulations that revealed that bottleneck tests can have limited statistical power to detect bottlenecks largely as a result of limited sample sizes typically used in published studies. Moreover, commonly assumed values for mutation model parameters do not appear to encompass variation in microsatellite evolution observed in vertebrates and, on average, the proportion of multi-step mutations is underestimated by a factor of approximately two. As a result, bottleneck tests can have a higher probability of 'detecting' bottlenecks in stable populations than expected based on the nominal significance level. We provide recommendations that could add rigor to inferences drawn from future bottleneck tests and highlight new directions for the characterization of demographic history.  相似文献   
1000.
大多数国家对转基因生物研究与产业化日趋积极,把发展生物技术作为支撑发展、引领未来的战略选择,力求抢占新一轮经济和科技革命的先机与制高点。随之而来的是公众对转基因产品安全性的关注。转基因生物成分分析作为安全性评价的重要内容,发挥着举足轻重的作用,而基于PCR技术的转基因产品核酸成分分析是最经典、最广泛使用的方法。虽然此方法已普遍应用,但国内外鲜有较为全面的阐述此类分析测试要素的报道。为此,本综述对国内外相关方法的文献资料进行了梳理、比对和研究,结合已有的分析测试实验室的经验,提出了PCR测试体系的关键要素主要是标准和指南、方法的确认、标准物质及能力验证等四个方面,且在文中简明扼要的论述了各个部分的要点,供转基因核酸成分分析及相关领域工作者参考。  相似文献   
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