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   12580篇
  免费   791篇
  国内免费   539篇
耳鼻咽喉   14篇
儿科学   65篇
妇产科学   682篇
基础医学   775篇
口腔科学   307篇
临床医学   1323篇
内科学   587篇
皮肤病学   29篇
神经病学   300篇
特种医学   575篇
外科学   3929篇
综合类   2285篇
现状与发展   2篇
预防医学   355篇
眼科学   647篇
药学   618篇
  14篇
中国医学   1322篇
肿瘤学   81篇
  2024年   43篇
  2023年   207篇
  2022年   362篇
  2021年   494篇
  2020年   513篇
  2019年   323篇
  2018年   346篇
  2017年   397篇
  2016年   441篇
  2015年   429篇
  2014年   1068篇
  2013年   922篇
  2012年   866篇
  2011年   911篇
  2010年   806篇
  2009年   639篇
  2008年   644篇
  2007年   626篇
  2006年   514篇
  2005年   455篇
  2004年   396篇
  2003年   352篇
  2002年   306篇
  2001年   257篇
  2000年   213篇
  1999年   199篇
  1998年   141篇
  1997年   127篇
  1996年   119篇
  1995年   99篇
  1994年   98篇
  1993年   85篇
  1992年   72篇
  1991年   49篇
  1990年   27篇
  1989年   49篇
  1988年   32篇
  1987年   36篇
  1986年   34篇
  1985年   49篇
  1984年   38篇
  1983年   14篇
  1982年   31篇
  1981年   19篇
  1980年   12篇
  1979年   13篇
  1978年   14篇
  1977年   12篇
  1976年   2篇
  1975年   4篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
黎作旭  张世民 《中国骨伤》2004,17(11):692-693
儿童颈椎间盘钙化症(cervical incervertebral dise calcification in children)是一种少见的疾病。1924年Baron首先报道本病.国内1982年至今陆续报道,迄今仅百余例。作者经治儿童颈椎间盘钙化症5例.结合文献对其诊断和治疗加以讨论。  相似文献   
12.
目的观察硬膜外间隙注药配合牵引治疗腰椎间盘突出症。方法162例经体查,X线、CT、MRI摄片确诊为腰椎间盘突出症。硬膜外间隙注入利多卡因lmg/kg与强的松龙lmg/kg的混合液10ml,注药1次/7d,3次为一疗程。并行牵引4h/d。结果疗效优良率94.4%。结论此疗效确切。  相似文献   
13.
腰椎间盘突出是骨科常见病。CT扫描能够显示间盘组织的直接影像,是诊断间盘病变的重要方法。本文对80例腰间盘突出进行分析,探讨CT对腰间盘突出的诊断价值。1 材料和方法 1.1一般资料 选用临床及CT表现均典型病例80例,男13例,女37例,年龄17岁-74岁,病程最短2d,最长22a,  相似文献   
14.
The objective was to determine whether vaginal topography accurately predicts the location of the pelvic viscera on fluoroscopy in women with pelvic organ prolapse. Eighty-nine women undergoing preoperative evaluation for reconstructive pelvic surgery at a tertiary care referral practice formed the study population. Each woman completed a comprehensive urogynecologic history and physical examination, which included a quantified (POP-Q) assessment of her vaginal topography, as described by Bump et al. In addition each woman underwent pelvic floor fluoroscopy (PFF). Visceral sites were selected which corresponded clinically to the vaginal sites measured by the POP-Q. The most dependent portion of the bladder, small intestine, rectum and urethrovesical junction was measured. Twenty-five (28%) women had stage II prolapse, 34 (38%) had stage III prolapse, and 28 (32%) had stage IV prolapse. The remaining 2 women were symptomatic, with stage I prolapse. For the entire study population there was no correlation between the fluoroscopic position of the small bowel and/or rectum and any apical or posterior wall POP-Q site (C, Ap or Bp). There was no correlation with the fluoroscopic position of the UVJ at rest or with straining and the corresponding POP-Q site (Aa). The fluoroscopic position of the most dependent portion of the bladder correlated only modestly with the upper (Ba,ρ=0.51) and lower Aa,ρ=0.68) anterior vaginal wall POP-Q sites. In women without prior surgery (n=33) there was only modest correlation between the fluoroscopic position of the bladder and the corresponding POP-Q site (Aa,ρ=0.71). In this unoperated subpopulation there was no correlation with PFF and any other POP-Q site. In women who had undergone prior hysterectomy (n=25) or hysterectomy with anterior and/or posterior colporrhaphy (n=17), there was only a modest correlation of the most dependent portion of the bladder and the upper anterior vaginal wall site (Bb,ρ=0.67 andρ=0.55, respectively). It was concluded that vaginal topography does not reliably predict the position of the associated viscera on PFF in women with primary or recurrent pelvic organ prolapse. EDITORIAL COMMENT: The authors seek to evaluate whether physical examination of vaginal prolapse using the POP-Q test correlates with fluoroscopic findings of visceral position. Surprisingly, little correlation is found, even in previously unoperated patients. One reason for this lack of correlation between the two modalities of evaluation may lie in the use of two different fixed points of reference: the POP-Q examination uses the hymen as the fixed point of reference, whereas the investigators chose to use the posterior edge of the femur as a fixed bony point of reference when evaluating pelvic floor fluoroscopy in the same patient. The lack of correlation between visual inspection of vaginal wall prolapse and what lies deep to that prolapse should not be used to invalidate the use of the POP-Q as a means to evaluate pelvic prolapse. Rather, the findings support the premise behind the ICS/AUGS/SGS committee on pelvic organ prolapse, specifically that clinical pelvic examination of the vaginal walls looks at surfaces only, and as such cannot determine what, if any, organ lies deep to that surface.  相似文献   
15.
采用经皮弧式椎间盘切除器械治疗L_5~S_1椎间盘突出症22例,21例成功。术后优良率为86.4%。该器械能够避开髂嵴阻挡进入L_5~S_1椎间隙,并增加椎间盘切除量,提高经皮L_5~S_1椎间盘切除成功率。定位正确是成功的关键。  相似文献   
16.
This work is a review of the mechanical factors related to low back pain production in a vibration environment. The sitting posture is an extreme orientation for the lumbar intervertebral disc that 1) increases its internal pressure, 2) increases its anteroposterior shear flexibility, while: 3) decreasing its resistance to buckling instability and 4) stressing the posterior region of the disc. Vibration is an additional mechanical stressor. Several studies suggest that the following preventive measures be taken to reduce the risk of low back pain due to driving: 1) minimize the vibration reaching the driver, 2) avoid lifting or bending immediately following driving, and 3) walk around for a few minutes following driving. © 1993 Wiley-Liss, Inc.  相似文献   
17.
考察了开式涡轮转盘塔(OTRDC)中的分散相滞留率和液泛特性。采用五种不同的液-液体系,在两种不同直径的塔中进行了实验。给出了估算分散相滞留率的关联式及无传质时临界转速的判据,进而大体上确认了OTRDC的操作区域。  相似文献   
18.
We studied 14 patients from three unrelated Belgian pedigrees with a familial mitochondrial disorder and multiple deletions of mitochondrial DNA (mtDNA). In one family with an oculopharyngeal presentation there is a clear autosomal dominant inheritance. Progressive external ophthalmoplegia (PEO), “ragged red fibres” (RRF) and multiple deletions of mtDNA are common to all three families. Therefore a diagnosis of autosomal dominant progressive ophthalmoplegia with multiple deletions of mtDNA (adPEO) was made in one family at least. Our data confirm the previous observations that adPEO is a systemic disorder rather than a pure myopathy. In our pedigrees frequently associated features include axonal peripheral neuropathy, dysphagia, psychiatric illness, and sudden death. Mild ataxia, pes cavus and mitral valve prolapse with associated mitral insufficiency also occur. In some cases onset is atypical with neuropathy, adolescent onset myopathy or psychiatric illness. In such cases the common features of PEO and muscle weakness always complete the clinical phenotype later during the course of the disease. Biochemical studies on mitochondrial fractions prepared from one patient's muscle, revealed no abnormalities of respiratory chain enzyme activities.  相似文献   
19.
The inability to completely mobilize the redundant colon in perineal rectosigmoidectomy (Altemeier's procedure) for full-thickness rectal prolapse is a main contributor to the recurrence rate associated with the procedure. However, the presence of a redundant sigmoid after the Ripstein procedure or other rectal sling operations is the main cause of the high rate of postoperative constipation and stool impaction. Low anterior resection as the definitive treatment is associated with the higher morbidity of laparotomy and the risk of anastomotic leak. We describe a laparoscopic-assisted surgical approach which combines the benefits of completely resecting the redundant sigmoid colon as well as the performance of extraperitoneal anastomosis at the level of the anus. Received: 22 April 1996/Accepted: 16 May 1996  相似文献   
20.
报告手术治疗腰椎间盘突出症合并退行性腰椎管狭窄症104例。术后随访90例,随诊时6个月~6年。优良率86.5%,无腰椎不稳和腰椎滑脱等并发症。为获得优良效果,作者强调在处理椎间盘突出的同时必须彻底解除侧隐窝及神经根管,黄韧带肥厚对神经根的压迫,才能彻底根除症状  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