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   933654篇
  免费   67690篇
  国内免费   1348篇
耳鼻咽喉   12985篇
儿科学   24421篇
妇产科学   23288篇
基础医学   133362篇
口腔科学   28313篇
临床医学   80741篇
内科学   184016篇
皮肤病学   19254篇
神经病学   72409篇
特种医学   36924篇
外国民族医学   79篇
外科学   152437篇
综合类   18068篇
现状与发展   1篇
一般理论   234篇
预防医学   61852篇
眼科学   21380篇
药学   72843篇
  3篇
中国医学   2164篇
肿瘤学   57918篇
  2018年   9012篇
  2017年   7072篇
  2016年   7822篇
  2015年   8908篇
  2014年   12055篇
  2013年   17584篇
  2012年   24230篇
  2011年   25205篇
  2010年   14914篇
  2009年   14366篇
  2008年   24787篇
  2007年   25910篇
  2006年   26682篇
  2005年   25605篇
  2004年   24760篇
  2003年   23750篇
  2002年   23320篇
  2001年   54795篇
  2000年   56605篇
  1999年   47021篇
  1998年   10770篇
  1997年   9503篇
  1996年   9616篇
  1995年   8952篇
  1994年   8302篇
  1993年   7604篇
  1992年   35527篇
  1991年   33953篇
  1990年   32759篇
  1989年   31912篇
  1988年   29026篇
  1987年   28270篇
  1986年   26310篇
  1985年   25167篇
  1984年   17843篇
  1983年   15154篇
  1982年   7808篇
  1981年   6778篇
  1979年   15791篇
  1978年   10608篇
  1977年   9061篇
  1976年   7880篇
  1975年   8642篇
  1974年   10481篇
  1973年   9870篇
  1972年   9370篇
  1971年   8864篇
  1970年   8447篇
  1969年   7931篇
  1968年   7207篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
41.
42.
Abstract

Objective: To understand the origin of extremely high gonadotropin levels in a perimenopausal woman.

Methods: A 52-year-old woman with a 2?months of amenorrhea followed spontaneous menstrual cycles recovery was referred to our outpatient clinic with elevated follicle-stimulating hormone (FSH, 483 mUI/ml), luteinizing hormone (LH, 475 mUI/ml) and prolactin (PRL, 173?ng/ml). She was known to take levosulpiride. The gonadotropin levels did not fit with the clinical features.

Results: A gonadotroph tumor was ruled out. Further analysis confirmed constantly high FSH, LH and PRL levels. The measurements were repeated using different analytical platforms with different results. After serial dilutions, nonlinearity was present suggesting an immunoassay interference. After post-polyethylene glycol recovery, hormone levels appeared in the normal range. Anti-goat antibodies were recognized in the serum of the patient.

Conclusions: This case report shows a case of falsely abnormal high gonadotropin and PRL levels in a woman during menopause transition. In the clinical practice the evaluation of gonadotropin profile is not recommended at this age, but the abnormal levels stimulated further evaluation. An interference in the assay due to anti-goat antibodies resulted in abnormally high level of FSH and LH. A strict collaboration between clinicians and the laboratory is needed, when laboratory findings do not correspond to clinical findings.  相似文献   
43.
44.
45.
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   
46.
47.
48.
49.
Two cultivars of Japanese parsley were harvested in different seasons; their antioxidant capacities were evaluated by oxygen radical absorbance capacity (ORAC) methods, and the contents of hydrophilic and lipophilic antioxidants were compared. Japanese parsley possessed potent antioxidant capacities both in hydrophilic and lipophilic extracts when evaluated by ORAC methods. LC/MS/MS analyses revealed that chlorogenic acid and four kinds of quercetin glycosides were major antioxidants in the hydrophilic extract. Lutein was the main contributor to the antioxidant capacity of the lipophilic extract. Antioxidant capacities of the hydrophilic extracts of both cultivars tended to be higher in winter because of the increase in the contents of chlorogenic acid and quercetin glycosides. An obvious trend in the lipophilic antioxidant capacities or lutein contents was not observed irrespective of the cultivar.  相似文献   
50.
Journal of Thrombosis and Thrombolysis - Amniotic fluid embolism (AFE) is a catastrophic condition in the peripartum period and still remains as a leading cause of maternal death. Although over 80%...  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