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   65800篇
  免费   5028篇
  国内免费   1737篇
耳鼻咽喉   710篇
儿科学   1483篇
妇产科学   1331篇
基础医学   7255篇
口腔科学   1413篇
临床医学   6914篇
内科学   13531篇
皮肤病学   1411篇
神经病学   3914篇
特种医学   1441篇
外国民族医学   7篇
外科学   7797篇
综合类   6285篇
现状与发展   2篇
一般理论   13篇
预防医学   5560篇
眼科学   1572篇
药学   5773篇
  53篇
中国医学   2342篇
肿瘤学   3758篇
  2024年   175篇
  2023年   771篇
  2022年   1801篇
  2021年   2979篇
  2020年   2060篇
  2019年   2103篇
  2018年   2396篇
  2017年   2005篇
  2016年   1740篇
  2015年   2436篇
  2014年   3242篇
  2013年   3842篇
  2012年   5747篇
  2011年   5909篇
  2010年   3816篇
  2009年   3284篇
  2008年   4281篇
  2007年   4204篇
  2006年   3761篇
  2005年   3426篇
  2004年   2743篇
  2003年   2564篇
  2002年   2145篇
  2001年   640篇
  2000年   565篇
  1999年   504篇
  1998年   340篇
  1997年   302篇
  1996年   278篇
  1995年   229篇
  1994年   185篇
  1993年   140篇
  1992年   172篇
  1991年   131篇
  1990年   134篇
  1989年   122篇
  1988年   106篇
  1987年   112篇
  1986年   105篇
  1985年   94篇
  1984年   83篇
  1983年   85篇
  1982年   89篇
  1981年   92篇
  1980年   56篇
  1979年   71篇
  1978年   43篇
  1977年   51篇
  1976年   41篇
  1974年   46篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
91.
外刊速览     
中国私立医院风头正劲——华尔街日报作为一家大律师事务所的高级合伙人,庄先生说,他可以很轻松地花7万美元买一辆进口宝马(BMW)车,或1.2 万美元买块Jaeger-LeCoultre金表。但去年,当这位律师患上偏头痛时,他却不得不排着长队,忍受着粗暴的服务,到固营医院去看病。而费用仅仅是6美元。因为是有钱人,庄先生没有透露他的全名。他说宁愿多花点钱,也希望享受到方便舒适的医疗服务。去年底,他  相似文献   
92.
During PTCA immediate decisions often must be made on the basis of a less than optimum data set. We present a combination of factors which produce an incorrect perception of a coronary artery dissection. This potential must be understood by the interventionalist to avoid misdiagnosis and inappropriate therapeutic maneuvers. © 1993 Wiley-Liss, Inc.  相似文献   
93.
Interobserver variability in neonatal cranial ultrasonography   总被引:1,自引:0,他引:1  
The reliability of cranial ultrasound diagnosis in the premature neonate was examined using data from an ongoing multicentre study of the epidemiology and long-term consequences of neonatal brain haemorrhage. First week ultrasound films (obtained at 4 hours, 24 hours and 7 days) from 60 study subjects were randomly selected for independent review by two groups of experienced interpreters, and results were recorded separately for observations (i.e. presence or absence of an abnormal echodense area on a film) and interpretations (i.e. presence or absence of haemorrhage or ventricular dilatation) in each hemisphere. Because of deaths in the first week of life, the total number of films examined was 138. Concordance on the presence or absence of an abnormal echodensity was examined for each individual film for three areas of interest: the germinal matrix, the ventricles and the parenchyma. Concordance on the presence or absence of haemorrhage or ventricular dilatation was examined only for the seventh-day film, or the final film prior to death. Finally, concordance was analysed with the diagnostic interpretations grouped into categories thought to differ prognostically for long-term outcome. In general, concordance was poorest for germinal matrix lesions and best for parenchymal lesions. Concordance was lower for observations made on each individual film than it was for interpretation of the final film in each case. Fifty-five of 60 cases (92%) were assigned to the same major prognostic category by both readers. Ultrasound review conferences were held periodically and there was evidence that concordance in ultrasound reading and interpretation improved during the course of the study.  相似文献   
94.
儿童感觉统合失调及其影响因素的调查分析   总被引:17,自引:1,他引:16  
目的 研究儿童感觉统合失调与学习障碍及环境因素的关系。方法 采用感觉统合评定量表和学习障碍(PRS)筛查量表,分别对755名学龄儿童进行检测、分析。结果 感觉统合严重失调率为13.25%;感觉统合正常与失调儿童的学习障碍有统计学差异(P<0.005);其中在LD儿童中感觉统合失调率占63.51%;感觉统合失调与母孕期的情绪、是否足月顺产、出生后的喂养方式、居住环境、孩子1岁内有无高热、家长对孩子的态度及期待等因素有关(P<0.05)。结论 儿童感觉统合失调与环境因素、学习障碍有一定的关系。  相似文献   
95.
BACKGROUND: Immunosuppression therapy with bolus glucocorticoids causes regional osteoporosis in the axial skeleton of heart transplant recipients (HTR). No preventive strategy is generally accepted for steroid-induced bone loss. METHODS: To determine the efficacy of an anti-osteoporosis regimen that combined a bisphosphonate agent (alendronate sodium) with the osteogenic stimulus of mechanical loading, 25 HTRs were randomly assigned either to a group that received alendronate (10 mg/day) for 6 months (ALEN; n = 8), a group that received alendronate (10 mg/day) and performed specific resistance exercises for 6 months (ALEN + TRN; n = 8) or to a non-intervention control group (CONTR; n = 9). Alendronate was initiated at 2 months after transplantation. Bone mineral density (BMD) of the total body, femur neck and lumbar spine (L-2 and L-3) was measured by dual-energy X-ray absorptiometry before and 2, 5 and 8 months after transplantation. Resistance training consisted of lumbar extension exercise (MedX) performed 1 day/week and 8 variable resistance exercises (MedX) performed 2 days/week. RESULTS: Pre-transplantation BMD values did not differ among the 3 groups. BMD of the total body, femur neck and lumbar vertebra were significantly decreased below baseline at 2 months after transplantation in CONTR (-2.6 +/- 0.9%, -5.1 +/- 1.8%, -12.5 +/- 4.2%, respectively), ALEN (-2.8 +/- 0.8%, -5.3 +/- 1.6%, -12.0 +/- 3.9%) and ALEN + TRN groups (-2.7 +/- 1.0%, -5.6 +/- 2.1%, -11.2 +/- 3.7%). CONTR had further significant losses of BMD after 3 and 6 months. ALEN had no further regional BMD losses after initiation of alendronate therapy. ALEN + TRN restored BMD of the whole body, femur neck and lumbar vertebra to within 0.9%, 2.1%, and 3.4% of pre-transplantation levels, respectively. CONCLUSIONS: Resistance exercise plus alendronate was more efficacious than alendronate alone in restoring BMD in HTRs. Our results indicate that anti-osteoporosis therapy in this population should include both an anti-resorptive agent as well as an osteogenic stimulus, such as mechanical loading.  相似文献   
96.
双频谱指数在心脏瓣膜置换术中的观察   总被引:2,自引:0,他引:2  
目的应用脑电双频谱指数(BIS)监测常规经验麻醉下瓣膜置换术病人的麻醉深度(意识水平),观察BIS在伤害性刺激时的变化.方法选择30例瓣膜置换术病人,采用芬太尼、咪唑安定、哌库溴铵及心血管活性药物对病人实施麻醉;术中监测并有专人分别记录入室(基础值)、诱导后、插管后、切皮后、锯胸骨时、缝胸骨时及术毕BIS和MAP,HR各参数值,观察不同阶段各参数的变化.结果诱导后各参数均明显降低,虽然切皮后、锯胸骨及缝胸骨等强刺激后MAP和HR未见统计学意义的显著改变,但BIS却显著增高(P<0.01);全部病人锯胸骨时BIS均在60(67.28±8.97)以上,缝胸骨时63(68.46±8.70)以上,而无1例低于50者.结论该组瓣膜置换术病人麻醉偏浅,尤以锯胸骨、缝胸骨及术毕等时段为甚,表现为BIS值偏高,有知晓发生;知晓可发生在临床认为满意的麻醉中;应用BIS监测,可更加合理地评价麻醉深度.  相似文献   
97.
Older age is not considered a contraindication for liver transplantation, but age-related morbidity may be a cause of mortality. Survival and the incidence of the main post-transplant complications were assessed in 111 adult liver transplant recipients. They were divided in two groups according to their age (patients younger than 60 years, n=54; patients older than 60 years, n=57) and both groups were compared. Older patients were more frequently transplanted for hepatitis C (p= 0.03) and hepatocellular carcinoma (p= 0.05) and their liver disease was less advanced (Child-Pugh and MELD scores were significantly lower; p=0.004 and p=0.05, respectively). After transplantation, older patients had a significantly lower survival (p=0.02). Higher age was independently associated with mortality (hazard ratio for each 10-year increase: 2.1; 95% confidence interval: 1.1- 4.0; p=0.02). The incidence of de novo neoplasia and nonskin neoplasia were higher in older patients (p=0.02 and p =0.007, respectively). Malignancy was the cause of death in one patient younger than 60 years and in 12 patients older than 60 years (p =0.002). In multivariate analysis, a higher age and smoking were independently associated with a higher risk of dying of de novo neoplasia. In conclusion, older liver transplant recipients have a significantly lower survival than younger patients. Malignancy is responsible for this decreased survival.  相似文献   
98.
99.
目的探讨高血压合并脑梗死患者急性期血浆C-反应蛋白(CRP)、纤维蛋白原(Fib)水平、白细胞(WBC)及分类计数的变化与高血压合并脑梗死的关系。方法将患者分为两组,高血压合并脑梗死组(68例)和单纯高血压组(65例),检测两组患者急性期血浆CRP、Fib和WBC水平。结果高血压合并脑梗死患者急性期CRP、Fib水平、WBC总数、中性粒细胞数均比单纯高血压患者明显增高(P<0.01)。结论C-反应蛋白、纤维蛋白原和白细胞升高可能与脑梗死的发生和进展相关,抗炎治疗可能是脑梗死治疗的一个选择。  相似文献   
100.

Background  

Official guidelines that promote evidence-based and cost-effective prescribing are of main relevance for obvious reasons. However, to what extent these guidelines are followed and their conditioning factors at different levels of the health care system are still insufficiently known.  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