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   1629096篇
  免费   136370篇
  国内免费   4923篇
耳鼻咽喉   21865篇
儿科学   53165篇
妇产科学   46544篇
基础医学   231304篇
口腔科学   47668篇
临床医学   145274篇
内科学   318701篇
皮肤病学   34326篇
神经病学   131653篇
特种医学   65752篇
外国民族医学   495篇
外科学   246497篇
综合类   45052篇
现状与发展   8篇
一般理论   546篇
预防医学   124470篇
眼科学   37606篇
药学   124653篇
  28篇
中国医学   4849篇
肿瘤学   89933篇
  2018年   15844篇
  2016年   13865篇
  2015年   16571篇
  2014年   22452篇
  2013年   32827篇
  2012年   44762篇
  2011年   47210篇
  2010年   27798篇
  2009年   26426篇
  2008年   44513篇
  2007年   46732篇
  2006年   47599篇
  2005年   46426篇
  2004年   45035篇
  2003年   43000篇
  2002年   42049篇
  2001年   76296篇
  2000年   78928篇
  1999年   67104篇
  1998年   18242篇
  1997年   16822篇
  1996年   16694篇
  1995年   16376篇
  1994年   15368篇
  1993年   14424篇
  1992年   55631篇
  1991年   53968篇
  1990年   52744篇
  1989年   50970篇
  1988年   47356篇
  1987年   46656篇
  1986年   44371篇
  1985年   42903篇
  1984年   32058篇
  1983年   27589篇
  1982年   16154篇
  1981年   14454篇
  1980年   13572篇
  1979年   30468篇
  1978年   21064篇
  1977年   17764篇
  1976年   16694篇
  1975年   17574篇
  1974年   21486篇
  1973年   20672篇
  1972年   18853篇
  1971年   17770篇
  1970年   16289篇
  1969年   15268篇
  1968年   13949篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
81.
Background Immune checkpoint blockers (ICBs) activate CD8+ T cells, eliciting both anti-cancer activity and immune-related adverse events (irAEs). The relationship of irAEs with baseline parameters and clinical outcome is unclear.Methods Retrospective evaluation of irAEs on survival was performed across primary (N = 144) and secondary (N = 211) independent cohorts of patients with metastatic melanoma receiving single agent (pembrolizumab/nivolumab—sICB) or combination (nivolumab and ipilimumab—cICB) checkpoint blockade. RNA from pre-treatment and post-treatment CD8+ T cells was sequenced and differential gene expression according to irAE development assessed.Results 58.3% of patients developed early irAEs and this was associated with longer progression-free (PFS) and overall survival (OS) across both cohorts (log-rank test, OS: P < 0.0001). Median survival for patients without irAEs was 16.6 months (95% CI: 10.9–33.4) versus not-reached (P = 2.8 × 10−6). Pre-treatment monocyte and neutrophil counts, but not BMI, were additional predictors of clinical outcome. Differential expression of numerous gene pathway members was observed in CD8+ T cells according to irAE development, and patients not developing irAEs demonstrating upregulated CXCR1 pre- and post-treatment.Conclusions Early irAE development post-ICB is associated with favourable survival in MM. Development of irAEs is coupled to expression of numerous gene pathways, suggesting irAE development in-part reflects baseline immune activation.Subject terms: Immunotherapy, Melanoma  相似文献   
82.
83.
Objective: To evaluate the effectiveness of a modified behavioral activation treatment (MBAT) intervention on reducing depressive symptoms in rural left-behind elderly.

Method: This is a randomized study registered in Chinese Clinical Trial Registry (ChiCTR-IOR-17011289). Eighty rural left-behind elderly people who had a Geriatric Depression Scale (GDS) score between 11 and 25 were randomly assigned to the intervention (n?=?40) and control group (n?=?40). The intervention group received both MBAT and regular treatment for 8 weeks while the control group received regular treatment. Both groups were assessed with the GDS, Beck Anxiety Inventory (BAI), and Oxford Happiness Questionnaire (OHQ) at baseline, immediately post-intervention, and at 3 months post-intervention.

Results: There were a total of 73 participants that completed the intervention. The scores of GDS and BAI decreased significantly, but the scores of OHQ increased significantly in the intervention group after 8 sessions of MBAT (P?<?.01). The reduction in depression symptoms after the intervention was maintained at the 3-month follow-up. Significant differences in GDS, BAI, and OHQ scores were observed between the intervention group and the control group (P?<?.01).

Conclusion: MBAT produced a significantly greater reduction in depressive symptoms than regular care in rural left-behind elderly.

Clinical or methodological significance of this article: A modified behavioral activation (BA) psychotherapy can significantly reduce the recurrence and seriousness of depression symptoms in the left-behind elderly with mild to moderate depression. This study also suggests that further study of the MBAT as an intervention will provide a direction for the management of mental health in rural left-behind elders.  相似文献   

84.
85.
86.
87.
88.
89.
90.
The aim of the present study was to evaluate the antimicrobial activity of two synbiotic combinations, Lactobacillus fermentum with short-chain fructooligosaccharides (FOS-LF) and Bifidobacterium longum with isomaltooligosaccharides (IMO-BL), against enterohaemorrhagic Escherichia coli O157:H7 and enteropathogenic E. coli O86. Antimicrobial activity was determined (1) by co-culturing the synbiotics and pathogens in batch cultures, and (2) with the three-stage continuous culture system (gut model), inoculated with faecal slurry from an elderly donor. In the co-culture experiments, IMO-BL was significantly inhibitory to both E. coli strains, while FOS-LF was slightly inhibitory or not inhibitory. Factors other than acid production appeared to play a role in the inhibition. In the gut models, both synbiotics effectively inhibited E. coli O157 in the first vessel, but not in vessels 2 and 3. E. coli O86 was not significantly inhibited.  相似文献   
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