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   1262785篇
  免费   95863篇
  国内免费   1575篇
耳鼻咽喉   16331篇
儿科学   41000篇
妇产科学   34948篇
基础医学   189387篇
口腔科学   34729篇
临床医学   117746篇
内科学   247800篇
皮肤病学   27278篇
神经病学   101848篇
特种医学   46758篇
外国民族医学   265篇
外科学   178576篇
综合类   25749篇
现状与发展   3篇
一般理论   568篇
预防医学   104649篇
眼科学   28044篇
药学   92565篇
  6篇
中国医学   2022篇
肿瘤学   69951篇
  2018年   13530篇
  2017年   10390篇
  2016年   11323篇
  2015年   13078篇
  2014年   17999篇
  2013年   27477篇
  2012年   37572篇
  2011年   39967篇
  2010年   23055篇
  2009年   22250篇
  2008年   37755篇
  2007年   40383篇
  2006年   39967篇
  2005年   39098篇
  2004年   37549篇
  2003年   35957篇
  2002年   34867篇
  2001年   56030篇
  2000年   57050篇
  1999年   48096篇
  1998年   13397篇
  1997年   12223篇
  1996年   12644篇
  1995年   11914篇
  1994年   11107篇
  1993年   10399篇
  1992年   38199篇
  1991年   37671篇
  1990年   36445篇
  1989年   35258篇
  1988年   32690篇
  1987年   32027篇
  1986年   30524篇
  1985年   28786篇
  1984年   21942篇
  1983年   19192篇
  1982年   11364篇
  1981年   10321篇
  1979年   20944篇
  1978年   15393篇
  1977年   12790篇
  1976年   11846篇
  1975年   12811篇
  1974年   15588篇
  1973年   15362篇
  1972年   14512篇
  1971年   13552篇
  1970年   12786篇
  1969年   12065篇
  1968年   11229篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
992.
993.
Coexistent primary hyperparathyroidism and monoclonal gammopathy, although rare, has been reported previously by a number of investigators. We report four patients with such an occurrence who were seen between 1976 and 1988. Another patient with primary hyperparathyroidism also had multiple myeloma and was in remission for 12 years. These patients represent approximately 1% of the 386 patients with primary hyperparathyroidism seen during the same 12-year period. Although several mechanisms have been proposed to explain this concurrence, we believe it is the result of a chance occurrence. A review of the literature, an estimate of the chance occurrence of coincidental monoclonal gammopathy, benign or malignant, in patients with primary hyperparathyroidism, and some practical implications of this interesting coexistence are presented.  相似文献   
994.
Concurrent acute onset of night terrors, somnambulism, and spontaneous daytime panic attacks meeting the criteria for panic disorder is reported in a 10-year-old boy with a family history of panic disorder. Both the parasomnias and the panic disorder were fully responsive to therapeutic doses of imipramine. A second case of night terrors and infrequent full symptom panic attacks is noted in another 10-year-old boy whose mother has panic disorder with agoraphobia. The clinical resemblance and reported differences between night terrors and panic attacks are described. The absence of previous reports of this comorbidity is notable. It is hypothesized that night terror disorder and panic disorder involve a similar constitutional vulnerability to dysregulation of brainstem altering systems.  相似文献   
995.
Spindles are a ubiquitous phenomenon in sleep, but their physiology and the effects of neurologic disorder on their frequency and amplitude are incompletely understood. We compared the incidence of three commonly defined spindle types (14-15 Hz, 12-13 Hz, and 10 Hz) and the frequency and amplitude of spindles during Stage II sleep in 50 patients with complex partial, partial and secondarily generalized, and primary generalized seizures, with and without interictal behavioral symptoms. All patients had 12-13 Hz and 14-15 Hz spindles of symmetric character in C3-A1 and C4-A2 derivations during prolonged sleep-deprived EEG recordings, which were normal except for partial or generalized epileptiform activity. Seventy-one per cent of complex partial seizure patients had 10 Hz spindles, and they occurred in 50% of the other two groups, predominating among those with interictal behavioral symptoms in all groups. Spindle frequency was significantly less in patients with generalized epilepsy than with partial seizures, and patients with complex partial seizures and partial seizures with secondary generalization differed significantly in spindle frequency. Spindle frequency was significantly lower with polypharmacy than with monotherapy. Patients whose regimens included phenobarbital had significantly lower spindle frequencies and spindle frequencies differed significantly between phenytoin and carbamazepine. Differences in spindle frequency may be due to residual medication effects, underlying encephalopathy or physiological differences between partial and generalized epilepsy.  相似文献   
996.
997.
The efficacy of intravenous thrombolytic agents in preserving left ventricular function and in decreasing mortality from an acute myocardial infarction was demonstrated in the 1980s. The 1990s will concentrate on adjunctive therapy to thrombolysis in the treatment of an acute myocardial infarction.  相似文献   
998.
999.
1000.
OBJECTIVES: To determine maternal responses to detection of a minor structural variant, the choroid plexus cyst (CPC), in their fetus on prenatal ultrasound. STUDY DESIGN: We interviewed 34 pregnant women with an isolated CPC detected on mid-pregnancy ultrasound about their objective experience at diagnosis, emotional response and subsequent reactions. Audiotaped, transcribed responses were evaluated by two independent raters and analyzed qualitatively and quantitatively. RESULTS: All women reported negative emotional responses including shock, distress, fear and decreased attachment, despite counseling by 82% of providers that the CPC was probably benign. Three women underwent amniocentesis purely for reassurance after CPC detection. Most (79%) sought information beyond what their physician provided, frequently on the internet. One half of women reported that intense negative responses were temporary. However, weeks after diagnosis, 62% continued to believe that the CPC presented some danger to their baby. CONCLUSIONS: Detection of CPC prenatally can evoke profound, negative maternal emotional responses despite accurate provider counseling. Practitioners should consider these responses when counseling parents about these and other structural variants of unclear functional significance.  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