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   2112619篇
  免费   171467篇
  国内免费   7615篇
耳鼻咽喉   27453篇
儿科学   70448篇
妇产科学   58645篇
基础医学   297954篇
口腔科学   58950篇
临床医学   192428篇
内科学   422891篇
皮肤病学   49427篇
神经病学   171811篇
特种医学   84667篇
外国民族医学   568篇
外科学   324208篇
综合类   50632篇
现状与发展   2篇
一般理论   761篇
预防医学   169061篇
眼科学   46839篇
药学   150415篇
  7篇
中国医学   3862篇
肿瘤学   110672篇
  2018年   21691篇
  2016年   19926篇
  2015年   22286篇
  2014年   31095篇
  2013年   47129篇
  2012年   59638篇
  2011年   63692篇
  2010年   39120篇
  2009年   37557篇
  2008年   59533篇
  2007年   63434篇
  2006年   64671篇
  2005年   62493篇
  2004年   60154篇
  2003年   58256篇
  2002年   55644篇
  2001年   99674篇
  2000年   102354篇
  1999年   85731篇
  1998年   25373篇
  1997年   22757篇
  1996年   23546篇
  1995年   23408篇
  1994年   21756篇
  1993年   20329篇
  1992年   70564篇
  1991年   68848篇
  1990年   66690篇
  1989年   64037篇
  1988年   58984篇
  1987年   58417篇
  1986年   54916篇
  1985年   53093篇
  1984年   40332篇
  1983年   33941篇
  1982年   21010篇
  1981年   18946篇
  1980年   17768篇
  1979年   36757篇
  1978年   26698篇
  1977年   22420篇
  1976年   20972篇
  1975年   21844篇
  1974年   25990篇
  1973年   25040篇
  1972年   23097篇
  1971年   21364篇
  1970年   19708篇
  1969年   18491篇
  1968年   17132篇
排序方式: 共有10000条查询结果,搜索用时 140 毫秒
71.
Obesity Surgery - Laparoscopic sleeve gastrectomy (LSG) is increasingly playing a key role in obesity management. Such operations, however, carry complications sometimes including leaks. The...  相似文献   
72.
Lasers in Medical Science - Studies reported the harmful effects of 2,4-D on body tissues, provoking changes in the anatomy and physiology of the kidneys, liver, and testicles. Thus, the objective...  相似文献   
73.
Background: Poor anger regulation is considered a risk factor of aggression in individuals with mild or borderline intellectual disabilities. Psychomotor therapy (PMT) targets anger regulation through body- and movement-oriented interventions. This study aims to inform practitioners on efficacy and research-base of PMT in this population.

Method: This systematic review evaluated nine studies which met inclusion criteria in terms of participants, intervention procedures, outcomes and certainty of evidence.

Results: Seven studies revealed a substantial reduction of aggressive behaviour or anger. Certainty of evidence was rated inconclusive in most cases due to absence of experimental control.

Conclusions: We can conclude that body-oriented PMT, involving progressive relaxation and meditation procedure “Soles of the Feet”, is a promising approach. However, the paucity of studies and methodological limitations preclude classifying it as an evidence-based practice. This suggests stronger methodological research and research aimed at PMT’s mechanisms of action (e.g., improved interoceptive awareness) is warranted.  相似文献   

74.
75.
76.

Background

Resistin is an immunometabolic mediator that is elevated in several inflammatory disorders. A ligand for Toll-like receptor 4, resistin modulates the recruitment and activation of myeloid cells, notably neutrophils. Neutrophils are major drivers of cystic fibrosis (CF) lung disease, in part due to the release of human neutrophil elastase- and myeloperoxidase-rich primary granules, leading to tissue damage. Here we assessed the relationship of resistin to CF lung disease.

Methods

Resistin levels were measured in plasma and sputum from three retrospective CF cohorts spanning a wide range of disease. We also assessed the ability of neutrophils to secrete resistin upon activation in vitro. Finally, we constructed a multivariate model assessing the relationship between resistin levels and lung function.

Results

Plasma resistin levels were only marginally higher in CF than in healthy control subjects. By contrast, sputum resistin levels were very high in CF, reaching 50–100 fold higher levels than in plasma. Among CF patients, higher plasma resistin levels were associated with allergic bronchopulmonary aspergillosis, and higher sputum resistin levels were associated with CF-related diabetes. Mechanistically, in vitro release of neutrophil primary granules was concomitant with resistin secretion. Overall, sputum resistin levels were negatively correlated with CF lung function, independently of other variables (age, sex, and genotype).

Conclusions

Our data establish relationships between resistin levels in the plasma and sputum of CF patients that correlate with disease status, and identify resistin as a novel mechanistic link between neutrophilic inflammation and lung disease in CF.  相似文献   
77.
Background Anti-EGFR-based therapies have limited success in HNSCC patients. Predictive biomarkers are greatly needed to identify the patients likely to be benefited from these targeted therapies. Here, we present the prognostic and predictive association of biomarkers in HPV-negative locally advanced (LA) HNSCC patients.Methods Treatment-naive tumour tissue samples of 404 patients, a subset of randomised Phase 3 trial comparing cisplatin radiation (CRT) versus nimotuzumab plus cisplatin radiation (NCRT) were analysed to evaluate the expression of HIF1α, EGFR and pEGFR by immunohistochemistry and EGFR gene copy change by FISH. Progression-free survival (PFS), locoregional control (LRC) and overall survival (OS) were estimated by Kaplan–Meier method. Hazard ratios were estimated by Cox proportional hazard models.Results Baseline characteristics of the patients were balanced between two treatment groups (CRT vs NCRT) and were representative of the trial cohort. The median follow-up was of 39.13 months. Low HIF1α was associated with better PFS [HR (95% CI) = 0.62 (0.42–0.93)], LRC [HR (95% CI) = 0.56 (0.37–0.86)] and OS [HR (95% CI) = 0.63 (0.43–0.93)] in the CRT group. Multivariable analysis revealed HIF1α as an independent negative prognostic biomarker. For patients with high HIF1α, NCRT significantly improved the outcomes [PFS:HR (95% CI) = 0.55 (0.37–0.82), LRC:HR (95% CI) = 0.55 (0.36–0.85) and OS:HR (95% CI) = 0.54 (0.36–0.81)] compared to CRT. While in patients with low HIF1α, no difference in the clinical outcomes was observed between treatments. Interaction test suggested a predictive value of HIF1α for OS (P = 0.008).Conclusions High HIF1α expression is a predictor of poor clinical response to CRT in HPV-negative LA-HNSCC patients. These patients with high HIF1α significantly benefited with the addition of nimotuzumab to CRT.Clinical trial registration Registered with the Clinical Trial Registry of India (Trial registration identifier—CTRI/2014/09/004980).Subject terms: Tumour biomarkers, Head and neck cancer, Tumour biomarkers, Head and neck cancer, Predictive markers  相似文献   
78.
Behçet disease is a complex, multisystem disease characterized by recurrent oral and genital ulcerations. It rarely occurs in infants or children. Neonatal Behçet disease has been reported in infants whose ulcers resolve at or before 9 weeks of age. Few cases of neonatal Behçet disease persisting into childhood have previously been reported. We report the case of a 1‐month‐old infant who presented with severe recurrent genital ulcerations and at 6 months developed recurrent oral ulcerations. Her orogenital ulcerations continue to recur. Human leukocyte antigen testing revealed HLA‐B51 and B44 positivity. This is a case of pediatric Behçet disease in the neonatal period. Behçet disease should be considered in the differential diagnosis of recurrent genital and oral ulcerations in infants and children.  相似文献   
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