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   1762261篇
  免费   136738篇
  国内免费   2999篇
耳鼻咽喉   23998篇
儿科学   59038篇
妇产科学   51151篇
基础医学   249005篇
口腔科学   52185篇
临床医学   153651篇
内科学   342743篇
皮肤病学   38069篇
神经病学   139592篇
特种医学   73685篇
外国民族医学   566篇
外科学   268755篇
综合类   40697篇
现状与发展   3篇
一般理论   546篇
预防医学   136881篇
眼科学   40277篇
药学   132491篇
  4篇
中国医学   3089篇
肿瘤学   95572篇
  2018年   17936篇
  2017年   15203篇
  2016年   15730篇
  2015年   19367篇
  2014年   24410篇
  2013年   34289篇
  2012年   51161篇
  2011年   48744篇
  2010年   28190篇
  2009年   28609篇
  2008年   44700篇
  2007年   47595篇
  2006年   48604篇
  2005年   54729篇
  2004年   55611篇
  2003年   49482篇
  2002年   44198篇
  2001年   78864篇
  2000年   79541篇
  1999年   70584篇
  1998年   18133篇
  1997年   16542篇
  1996年   16564篇
  1995年   16300篇
  1994年   15312篇
  1992年   60662篇
  1991年   59279篇
  1990年   58333篇
  1989年   56298篇
  1988年   52349篇
  1987年   51594篇
  1986年   49133篇
  1985年   47103篇
  1984年   34961篇
  1983年   29947篇
  1982年   16943篇
  1981年   15063篇
  1979年   33636篇
  1978年   23044篇
  1977年   19227篇
  1976年   18013篇
  1975年   19661篇
  1974年   24130篇
  1973年   23006篇
  1972年   21248篇
  1971年   20165篇
  1970年   18533篇
  1969年   17434篇
  1968年   15912篇
  1967年   14545篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
71.
Background A high Mandard score implies a non-response to chemotherapy in oesophageal adenocarcinoma. However, some patients exhibit tumour volume reduction and a nodal response despite a high score. This study examines survival and recurrence patterns in these patients.Methods Clinicopathological factors were analysed using multivariable Cox regression assessing time to death and recurrence. Computed tomography-estimated tumour volume change was examined in a subgroup of consecutive patients.Results Five hundred and fifty-five patients were included. Median survival was 55 months (Mandard 1–3) and 21 months (Mandard 4 and 5). In the Mandard 4 and 5 group (332 patients), comparison between complete nodal responders and persistent nodal disease showed improved survival (90 vs 18 months), recurrence rates (locoregional 14.75 vs 28.74%, systemic 24.59 vs 48.42%) and circumferential resection margin positivity (22.95 vs 68.11%). Complete nodal response independently predicted improved survival (hazard ratio 0.34 (0.16–0.74). Post-chemotherapy tumour volume reduction was greater in patients with a complete nodal response (−16.3 vs −7.7 cm3, p = 0.033) with no significant difference between Mandard groups.Conclusion Patients with a complete nodal response to chemotherapy have significantly improved outcomes despite a poor Mandard score. High Mandard score does not correspond with a non-response to chemotherapy in all cases and patients with nodal downstaging may still benefit from adjuvant chemotherapy.Subject terms: Oesophageal cancer, Surgical oncology  相似文献   
72.
73.
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   
74.
75.
76.
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   
77.
78.
79.
80.
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