首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2704篇
  免费   209篇
  国内免费   11篇
耳鼻咽喉   27篇
儿科学   108篇
妇产科学   52篇
基础医学   379篇
口腔科学   32篇
临床医学   177篇
内科学   646篇
皮肤病学   87篇
神经病学   155篇
特种医学   72篇
外科学   257篇
综合类   216篇
预防医学   338篇
眼科学   36篇
药学   201篇
中国医学   12篇
肿瘤学   129篇
  2023年   25篇
  2022年   43篇
  2021年   84篇
  2020年   45篇
  2019年   63篇
  2018年   66篇
  2017年   50篇
  2016年   68篇
  2015年   90篇
  2014年   110篇
  2013年   145篇
  2012年   179篇
  2011年   164篇
  2010年   103篇
  2009年   63篇
  2008年   139篇
  2007年   121篇
  2006年   118篇
  2005年   113篇
  2004年   100篇
  2003年   99篇
  2002年   104篇
  2001年   74篇
  2000年   78篇
  1999年   68篇
  1998年   21篇
  1997年   30篇
  1996年   23篇
  1995年   19篇
  1994年   16篇
  1993年   17篇
  1992年   39篇
  1991年   37篇
  1990年   28篇
  1989年   27篇
  1988年   26篇
  1987年   18篇
  1986年   27篇
  1985年   23篇
  1984年   19篇
  1979年   15篇
  1976年   14篇
  1975年   12篇
  1974年   18篇
  1973年   31篇
  1972年   11篇
  1970年   11篇
  1969年   11篇
  1968年   11篇
  1967年   11篇
排序方式: 共有2924条查询结果,搜索用时 15 毫秒
111.
112.

Objective

In developing countries like Bangladesh, delayed presentation for disorders of sex development (DSD) is common, and provides some special problems for management. There remains significant controversy about appropriate sex assignment in this group. We aimed, therefore, to assess gender identity (GI) in 50 consecutive patients with DSD presenting to a referral centre in Chittagong, Bangladesh, and correlate it with Prader score, to see if the latter could be used to predict GI.

Methods

A cross-sectional, case–control study of 50 consecutive children with DSD and 50 children with vascular anomalies was conducted in the Pediatric Surgical Clinic, Chittagong Medical College and Hospital. After informed consent, patients and controls provided oral answers to a GI questionnaire and had a detailed history and physical examination. Sex-typed activities were assessed by observations of a structured toy play and the child’s selection of a toy to keep. Both patients and parents then completed the Child Game Participation Questionnaire.

Results

There were no differences in age (2–16 years, mean 8.74) between controls and DSD patients (11 46, XX DSD, 32 46, XY DSD, 4 MGD, 3 ovo-testicular DSD). Fifteen of the DSD patients (30 %) came from consanguineous marriages and only 2 of the control patients had consanguinity of their parents. For the 13-question GI interview, there was no overall difference between DSD cases and controls. For the 46, XX DSD subgroup, there was a significantly higher score (11.1 ± 7.1) compared with control girls (4.5 ± 4.7) (p < 0.05), while for DSD and control boys, there was a positive correlation with age and GI (p < 0.01). Prader score correlated with GI score in both control (r = 0.91) and DSD patients (r = 0.75) (p < 0.01), DSD girls played significantly less with girls’ toys than controls (p < 0.01), but there was no differences for the boys. Composite scores on GI and gender-related behaviour correlated with Prader score for DSD patients (r = 0.61) (p < 0.01).

Conclusion

This study supports the view that GI and gender-role behaviour should be assessed routinely in DSD patients presenting after the neonatal period, so that sex assignment is in accordance with behaviour. Prader scores showed a good correlation with GI and gender role behaviour.  相似文献   
113.
114.
Coronavirus disease-19 (COVID-19) caused by SARS-CoV-2 has already killed more than one million people worldwide. Since novel coronavirus is a new virus, mining its genome sequence is of crucial importance for drug/vaccine(s) development. Whole genome sequencing is a helpful tool in identifying genetic changes that occur in a virus when it spreads through the population. In this study, we performed complete genome sequencing of SARS-CoV-2 to unveil the genomic variation and indel, if present. We discovered thirteen (13) mutations in Orf1ab, S and N gene where seven (7) of them turned out to be novel mutations from our sequenced isolate. Besides, we found one (1) insertion and seven (7) deletions from the indel analysis among the 323 Bangladeshi isolates. However, the indel did not show any effect on proteins. Our energy minimization analysis showed both stabilizing and destabilizing impact on viral proteins depending on the mutation. Interestingly, all the variants were located in the binding site of the proteins. Furthermore, drug binding analysis revealed marked difference in interacting residues in mutants when compared to the wild type. Our analysis also suggested that eleven (11) mutations could exert damaging effects on their corresponding protein structures.

SARS-CoV-2 mutational impact analysis.  相似文献   
115.
116.
117.
118.
119.
Averrhoa carambola L. (Oxalidaceae), Ficus hispida L.f. (Moraceae), and Syzygium samarangense (Blume) Merr. & L.M. Perry (Myrtaceae) are three common plants in Bangladesh, the fruits of which are edible. The leaves and fruits of A. carambola and F. hispida are used by folk medicinal practitioners for treatment of diabetes, while the leaves of S. samarangense are used for treatment of cold, itches, and waist pain. Since scientific studies are absent on the antihyperglycemic effects of the leaves of the three plants, it was the objective of the present study to evaluate the antihyperglycemic potential of methanolic extract of leaves of the plants in oral glucose tolerance tests carried out with glucose-loaded mice. The extracts at different doses were administered one hour prior to glucose administration and blood glucose level was measured after two hours of glucose administration (p.o.) using glucose oxidase method. Significant oral hypoglycemic activity was found with the extracts of leaves of all three plants tested. The fall in serum glucose levels were dose-dependent for every individual plant, being highest at the highest dose tested of 400 mg extract per kg body weight. At this dose, the extracts of A. carambola, F. hispida, and S. samarangense caused, respectively, 34.1, 22.7, and 59.3% reductions in serum glucose levels when compared to control animals. The standard antihyperglycemic drug, glibenclamide, caused a 57.3% reduction in serum glucose levels versus control. Among the three plants evaluated, the methanolic extract of leaves of S. samarangense proved to be the most potent in demonstrating antihyperglycemic effects. The result validates the folk medicinal uses of A. carambola and F. hispida in the treatment of diabetes, and indicates that the leaves of S. samarangense can also possibly be used for amelioration of diabetes-induced hyperglycemia.  相似文献   
120.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号