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   81776篇
  免费   7284篇
  国内免费   4561篇
耳鼻咽喉   952篇
儿科学   1037篇
妇产科学   858篇
基础医学   10283篇
口腔科学   1421篇
临床医学   8924篇
内科学   12149篇
皮肤病学   1456篇
神经病学   4082篇
特种医学   3987篇
外国民族医学   21篇
外科学   8408篇
综合类   12246篇
现状与发展   28篇
一般理论   9篇
预防医学   5448篇
眼科学   2466篇
药学   8727篇
  67篇
中国医学   3934篇
肿瘤学   7118篇
  2024年   189篇
  2023年   997篇
  2022年   2511篇
  2021年   3537篇
  2020年   2532篇
  2019年   2326篇
  2018年   2541篇
  2017年   2371篇
  2016年   2539篇
  2015年   3784篇
  2014年   4671篇
  2013年   4641篇
  2012年   6850篇
  2011年   7244篇
  2010年   4781篇
  2009年   4102篇
  2008年   5133篇
  2007年   4856篇
  2006年   4615篇
  2005年   4040篇
  2004年   3093篇
  2003年   3082篇
  2002年   2583篇
  2001年   1779篇
  2000年   1499篇
  1999年   1323篇
  1998年   812篇
  1997年   729篇
  1996年   609篇
  1995年   555篇
  1994年   529篇
  1993年   363篇
  1992年   403篇
  1991年   368篇
  1990年   324篇
  1989年   287篇
  1988年   196篇
  1987年   206篇
  1986年   157篇
  1985年   113篇
  1984年   60篇
  1983年   52篇
  1982年   40篇
  1981年   30篇
  1980年   32篇
  1979年   25篇
  1978年   13篇
  1976年   11篇
  1973年   18篇
  1972年   10篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
32.
OBJECTIVES: To assess the effectiveness and safety of additional bedtime H2‐receptor antagonists (H2RAs) in suppressing nocturnal gastric acid breakthrough (NAB) via a systematic review. METHODS: Eligible trials were identified by searching the Cochrane Central Register of Controlled Trials (CENTRAL) (Cochrane Library Issue 2, 2004), MEDLINE (January 1966–June 2004), EMBASE (January 1980–June 2004) and CINAHL (January 1982–June 2004). Additional hand‐searching was conducted on the proceedings of correlated conferences, eight important Chinese journals and references of all included trials. All randomized controlled trials evaluating H2RAs for the control of NAB were eligible for inclusion. The systematic review was conducted using methods recommended by The Cochrane Collaboration. RESULTS: Only two randomized crossover studies, comprising 32 participants, met the inclusion criteria. Because the design, dosage and duration of the treatments were different between the studies, it was not possible to conduct meta‐analysis. There were no consistent conclusions found between the two included studies in evaluating H2RAs for the control of NAB. CONCLUSIONS: No implications for practice at this stage can be concluded. Appropriately designed large‐scale randomized controlled trials with long‐term follow up are needed to determine the effects of additional bedtime H2RAs in suppressing NAB.  相似文献   
33.
Mutations in the gene encoding 11beta-hydroxysteroid dehydrogenase type 2, HSD11B2, cause a rare monogenic juvenile hypertensive syndrome called apparent mineralocorticoid excess (AME). In AME, defective HSD11B2 enzyme activity results in overstimulation of the mineralocorticoid receptor (MR) by cortisol, causing sodium retention, hypokalemia, and salt-dependent hypertension. Here, we have studied whether genetic variations in HDS11B2 are implicated in essential hypertension in Japanese hypertensives and the general population. By sequencing the entire coding region and the promoter region of HDS11B2 in 953 Japanese hypertensives, we identified five missense mutations in 11 patients (L14F, n = 5; R74H, n = 1; R147H, n = 3; T156I, n = 1; R335H, n = 1) and one novel frameshift mutation (4884Gdel, n = 1) in a heterozygous state, in addition to 19 genetic variations. All genetic variations identified were rare, with minor allele frequencies less than 0.005. Four of 12 patients with the missense/frameshift mutations showed renal failure. Four missense mutations, L14F, R74H, R147H, and R335H, were successfully genotyped in the general population, with a sample size of 3,655 individuals (2,175 normotensives and 1,480 hypertensives). Mutations L14F, R74H, R147H, and R335H were identified in hypertensives (n = 6, 8, 3, and 0, respectively) and normotensives (n = 8, 12, 5, and 0, respectively) with a similar frequency, suggesting that these missense mutations may not strongly affect the etiology of essential hypertension. Since the allele frequency of all of the genetic variations identified in this study was rare, an association study was not conducted. Taken together, our results indicate that missense mutations in HSD11B2 do not substantially contribute to essential hypertension in Japanese.  相似文献   
34.
目的了解我院门诊就诊者对子宫颈病变相关知识的认识。方法自制问卷调查表,采用无记名,当面问卷调查方式。结果从调查100例就诊者中,未做过健康体检、妇科盆腔检查和宫颈刮片检查分别为34例、24例和52例。对宫颈癌的认识不知道者53例。结论建议相关部门加强对妇女的健康教育,提高其健康意识,强化临床医生的防癌意识和对子宫病变的规范化诊治。  相似文献   
35.
胰腺假性囊肿的诊治体会   总被引:11,自引:0,他引:11  
目的 总结胰腺假性囊肿的诊治体会。方法 回顾性分析46例胰腺假性囊肿患者的临床资料,7例保守治疗,行内引流术12例,外引流术9例,序贯式内外引流术5例,胰腺部分切除术13例。结果 保守治疗者均痊愈,无复发;行内引流术者中有1例发生肠瘘,其余11例恢复良好无复发;行外引流术1例出现胰瘘,2例复发;行胰腺部分切除术者有1例出现胰瘘,其余恢复良好。结论 根据病情和病程选择合适的术式是治疗胰腺假性囊肿的关键。  相似文献   
36.
This paper describes the use of a composite graft from the mastoid area consisting of full-thickness skin peripherally and selectively localised fascia-fat tissue underneath the skin centrally for immediate reconstruction of moderate defects of the nasal tip including the columella and soft triangle. Mastoid composite grafting is a simple and safe procedure that avoids partial graft loss and provides adequate augmentation of soft tissue, easy reshaping of the new nostril rim, minimal post-operative shrinkage, and no donor-site morbidity. Then, it results in a satisfactory nasal appearance with adequate tip projection and symmetry. This procedure may represent a preferred method of nasal tip reconstruction.  相似文献   
37.
目的 探讨Lugol液染色对食管早期癌和癌前病变的诊断价值。方法 对45例食管黏膜可疑病变经内镜以2%Lugol液喷洒染色,观察黏膜染色情况,并取活检送病理组织学检查。结果 45例食管病变染色后,39例呈浅染色或不染色,其中食管癌8例(食管早期癌5例,进展期癌3例),Barrett食管5例,轻至中度不典型增生1l例。本组Lugol液染色对食管早期癌和癌前病变的检出率达46.7%。结论 内镜下应用Lugol液染色结合活检有助于食管早期癌和癌前病变的诊断,且操作简便,具有重要的临床价值。  相似文献   
38.
This article describes a modified suture technique designed for the vertical repair of the anterior horn of the meniscus after arthroscopic decompression of a large meniscal cyst. This procedure comprises of three steps: first, the meniscus was pierced vertically using a suture hook and a No. 0 PDS suture. Second, both ends of the No. 0 PDS on the femoral and tibial surfaces of the meniscus were pulled to the outside of the joint capsule using a spinal needle preloaded with suture material. Finally, a skin incision was made adjacent to the suture materials, and both ends were tied. We recommend this technique not only for the vertical repair of the anterior horn of the meniscus after decompression of large meniscal cyst, but also to repair a longitudinal tear of the meniscus.  相似文献   
39.
Ruptured aneurysms of the distal anterior choroidal artery (AchA) are extremely rare and management is dictated by clinical presentation. This report describes a rare patient with a distal AchA aneurysm and subarachnoid and intraventricular haemorrhage. A 60-year-old woman presented with a sudden onset of severe headache and vomiting. No aneurysms could be found on initial angiograms. A repeat angiogram performed 10 days after admission demonstrated an aneurysm in a branch of the cisternal segment of the left AchA without a definite neck. Surrounding vessels showed multifocal stricture and dilatation. Microsurgical clipping was not performed because the patient died suddenly due to pulmonary failure. The aetiology of the aneurysm in this case and surgical strategy are discussed.  相似文献   
40.
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