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   15279篇
  免费   1324篇
  国内免费   460篇
耳鼻咽喉   168篇
儿科学   279篇
妇产科学   376篇
基础医学   1988篇
口腔科学   319篇
临床医学   1758篇
内科学   2699篇
皮肤病学   308篇
神经病学   1052篇
特种医学   625篇
外国民族医学   3篇
外科学   1901篇
综合类   1129篇
一般理论   2篇
预防医学   977篇
眼科学   436篇
药学   1375篇
  4篇
中国医学   335篇
肿瘤学   1329篇
  2023年   153篇
  2022年   179篇
  2021年   482篇
  2020年   318篇
  2019年   413篇
  2018年   403篇
  2017年   371篇
  2016年   356篇
  2015年   518篇
  2014年   620篇
  2013年   682篇
  2012年   1116篇
  2011年   1186篇
  2010年   711篇
  2009年   596篇
  2008年   870篇
  2007年   846篇
  2006年   816篇
  2005年   764篇
  2004年   693篇
  2003年   595篇
  2002年   519篇
  2001年   462篇
  2000年   391篇
  1999年   386篇
  1998年   141篇
  1997年   137篇
  1996年   167篇
  1995年   145篇
  1994年   106篇
  1993年   85篇
  1992年   194篇
  1991年   182篇
  1990年   156篇
  1989年   134篇
  1988年   127篇
  1987年   106篇
  1986年   105篇
  1985年   103篇
  1984年   76篇
  1983年   70篇
  1982年   56篇
  1981年   55篇
  1980年   45篇
  1979年   60篇
  1978年   50篇
  1977年   33篇
  1975年   27篇
  1974年   43篇
  1968年   25篇
排序方式: 共有10000条查询结果,搜索用时 265 毫秒
1.
2.
帕金森病是以多巴胺能神经元减少导致的以静止性震颤、肌强直、运动迟缓和姿势步态障碍为主要临床症状的疾病。此病是蒙医白脉病的一种,又称彻彻热乎病。蒙医将人体的脉络分为白脉和黑脉。白脉病是白脉系统遭受致病因素的影响后所致的一系列疾病的总称,临床上很多疾病归属于“白脉病”。为更好的实现对蒙医优势单病种的规范化研究,本文基于白脉理论,探析蒙医对帕金森病的认识,以期为未来的研究提供理论支持。  相似文献   
3.
Network meta-analyses (NMAs) simultaneously estimate the effects of multiple possible treatment options for a given clinical presentation. For allergists to benefit optimally from NMAs, they must understand the process and be able to interpret the results. Through a worked example published in Pediatric Allergy and Immunology, we summarize how to identify credible NMAs and interpret them with a focus on recent innovations in the GRADE approach (Grading of Recommendations Assessment, Development, and Evaluation). NMAs build on traditional systematic reviews and meta-analyses that consider only direct paired comparisons by including indirect evidence, thus allowing the simultaneous assessment of the relative effect of all pairs of competing alternatives. Our framework informs clinicians of how to identify credible NMAs and address the certainty of the evidence. Trustworthy NMAs fill a critical gap in providing key inferences using direct and indirect evidence to inform clinical decision making when faced with more than two competing courses of treatment options. This document will help allergists to identify trustworthy NMAs to enhance patient care.  相似文献   
4.
5.
IntroductionHyperprogressive disease (HPD), characterized by accelerated tumor progression, has been proposed as a new pattern of progression after immune checkpoint inhibitor (ICI) treatment. The aim of this study was to describe the characteristics of HPD and investigate its predictive markers.MethodsClinical and radiological findings of 335 patients with advanced NSCLC treated with ICI monotherapy were retrospectively analyzed. Radiological data were quantitatively and longitudinally analyzed for tumor size and volume by comparing baseline and follow-up computerized tomography results. The findings were matched with individual genomic profiles generated by deep sequencing of 380 genes.ResultsAmong 135 patients with progressive disease (PD), as assessed by the Response Evaluation Criteria in Solid Tumors version 1.1 criteria, 48 (14.3% of all patients and 35.6% of those with PD) and 44 (13.1% of all patients and 32.6% among those with PD) were found to have HPD by volumetry (HPDV) and assessed by RECIST 1.1 (HPDR), respectively. Patients with HPDV were associated with significantly inferior overall survival (OS) versus that of patients without HPDV with PD (median OS = 4.7 months [95% confidence interval: 3.5–11.9)] versus 7.9 months [95% confidence interval: 6.0–13.5] [p = 0.004]); OS did not differ between patients without and without HPDR. HPDV status was an independent factor in OS. A derived neutrophil-to-lymphocyte ratio greater than 4 and lactate dehydrogenase level greater than the upper limit of normal were significantly associated with HPDV. Moreover, we identified coinciding KRAS and serine/threonine kinase 11 gene (STK11) mutations in the cohort of patients with HPDV (three of 16), whereas none were found in the cohort of patients without HPDV (zero of 28).ConclusionsDefining HPD treated with ICI on the basis of volumetric measurement is more precise than is defining it on the basis of one-dimensional analysis. Pre-ICI derived neutrophil-to-lymphocyte ratio, lactate dehydrogenase level, and concurrence of STK11 and KRAS mutations could thus be used as potential biomarkers for HPD prediction.  相似文献   
6.
目的:探讨对携带BRCA1/2突变的中国健康女性实施乳腺预防性切除及I期重建的可行性。方法:选择2018年1月至2019年2月3例于北京大学国际医院就诊的携带BRCA1/2突变的中国健康女性,其中2例携带BRCA1突变、1例携带BRCA2突变,均有乳腺癌家族史,年龄为34~36岁,实施预防性保留乳头-乳晕的双侧乳腺切除和Ⅰ期假体重建术。结果:3例患者术后无并发症发生,术后中位随访时间为18个月,均无乳腺癌发生,对重建乳房外形满意,且焦虑和恐惧情绪显著下降,取得良好的疗效。结论:对携带BRCA1/2突变且有乳腺癌家族史的中国健康女性,在严格筛选的基础上,可慎重开展乳腺预防性切除及Ⅰ期重建术。  相似文献   
7.
IntroductionThe relationships between morbid obesity, changes in body mass index (BMI) before cancer diagnosis, and lung cancer outcomes by histology (SCLC and NSCLC) have not been well studied.MethodsIndividual level data analysis was performed on 25,430 patients with NSCLC and 2787 patients with SCLC from 16 studies of the International Lung Cancer Consortium evaluating the association between various BMI variables and lung cancer overall survival, reported as adjusted hazard ratios (aHRs) from Cox proportional hazards models and adjusted penalized smoothing spline plots.ResultsOverall survival of NSCLC had putative U-shaped hazard ratio relationships with BMI based on spline plots: being underweight (BMI < 18.5 kg/m2; aHR = 1.56; 95% confidence interval [CI]:1.43–1.70) or morbidly overweight (BMI > 40 kg/m2; aHR = 1.09; 95% CI: 0.95–1.26) at the time of diagnosis was associated with worse stage-specific prognosis, whereas being overweight (25 kg/m2 ≤ BMI < 30 kg/m2; aHR = 0.89; 95% CI: 0.85–0.95) or obese (30 kg/m2 ≤ BMI ≤ 40 kg/m2; aHR = 0.86; 95% CI: 0.82–0.91) was associated with improved survival. Although not significant, a similar pattern was seen with SCLC. Compared with an increased or stable BMI from the period between young adulthood until date of diagnosis, a decreased BMI was associated with worse outcomes in NSCLC (aHR = 1.24; 95% CI: 1.2–1.3) and SCLC patients (aHR=1.26 (95% CI: 1.0–1.6). Decreased BMI was consistently associated with worse outcome, across clinicodemographic subsets.ConclusionsBoth being underweight or morbidly obese at time of diagnosis is associated with lower stage-specific survival in independent assessments of NSCLC and SCLC patients. In addition, a decrease in BMI at lung cancer diagnosis relative to early adulthood is a consistent marker of poor survival.  相似文献   
8.
9.
10.
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