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   1469篇
  免费   132篇
  国内免费   8篇
耳鼻咽喉   6篇
儿科学   79篇
妇产科学   30篇
基础医学   209篇
口腔科学   38篇
临床医学   219篇
内科学   278篇
皮肤病学   22篇
神经病学   72篇
特种医学   256篇
外国民族医学   13篇
外科学   174篇
综合类   29篇
预防医学   74篇
眼科学   11篇
药学   50篇
中国医学   6篇
肿瘤学   43篇
  2023年   13篇
  2022年   7篇
  2021年   21篇
  2020年   15篇
  2019年   14篇
  2018年   46篇
  2017年   23篇
  2016年   23篇
  2015年   37篇
  2014年   40篇
  2013年   47篇
  2012年   49篇
  2011年   55篇
  2010年   48篇
  2009年   69篇
  2008年   42篇
  2007年   28篇
  2006年   41篇
  2005年   26篇
  2004年   32篇
  2003年   32篇
  2002年   34篇
  2001年   39篇
  2000年   23篇
  1999年   23篇
  1998年   51篇
  1997年   54篇
  1996年   68篇
  1995年   54篇
  1994年   46篇
  1993年   54篇
  1992年   24篇
  1991年   24篇
  1990年   25篇
  1989年   40篇
  1988年   40篇
  1987年   40篇
  1986年   41篇
  1985年   35篇
  1984年   21篇
  1983年   19篇
  1982年   29篇
  1981年   19篇
  1980年   10篇
  1979年   13篇
  1978年   8篇
  1977年   19篇
  1976年   12篇
  1975年   17篇
  1969年   3篇
排序方式: 共有1609条查询结果,搜索用时 15 毫秒
71.
Simvastatin is a cholesterol-lowering drug that acts by inhibiting hydroxymethylglutaryl coenzyme A (HMG-CoA) reductase, the rate-limiting enzyme in cholesterol synthesis. Abnormal laboratory findings include transient increases in serum creatine kinase (CK) due to a myopathic syndrome. Rarely, neurological side effects include axonal sensory-motor peripheral neuropathy, characterized in some cases by a prevalent motor involvement accompanied by subclinical sensory damage. We report a case of purely motor axonal neuropathy associated with simvastatin. A 72-year-old woman, after five years of treatment with simvastatin, developed progressive weakness, cramps and fasciculations mainly involving proximal muscles in the lower limbs, though without sensory symptoms or signs. Deep reflexes were lost in the lower limbs. There was no sign of upper motor-neuron involvement. CK was elevated (up to 2000 U/l). EMG showed marked neurogenic damage with fibrillations and fasciculations in the lower limbs. ENG showed motor fiber loss within the lower limb nerves without involvement of sensory fibers. CSF examination was normal. Deltoid muscle biopsy showed neurogenic changes and some ragged-red fibers. One year after simvastatin withdrawal the patient's state of weakness improved and the cramps resolved. The CK level dropped to 700 U/l.  相似文献   
72.
73.
74.
It has been suggested that proliferation of enterobacteriaceae and/or anaerobes in the duodenum of some children with acute diarrhoea determines whether the episode becomes persistent. A review of published studies and the comparison of cultures of duodenal aspirates from Peruvian children with acute and persistent diarrhoea and diarrhoea-free children did not support this hypothesis. Although many children had enterobacteriaceae and/or anaerobes cultured there was no correlation with clinical and nutritional outcome. Age, nutritional status, the environment and the aetiology of the episode were determinants of the duodenal microflora independent of diarrhoea. Culture of the duodenal aspirates did not increase the yield of enteropathogens which were isolated more frequently from stools than from the duodenum. Despite the presence of a single strain or serotype of enterobacteriaceae suggesting that these bacteria were colonizing the duodenum, we were unable to demonstrate any adherence mechanisms in the majority of them. Two often bacteria with no other evidence of virulence caused diarrhoea in the RITARD rabbit model.  相似文献   
75.
The pathologic spectrum of uterotubal junction obstruction   总被引:3,自引:0,他引:3  
Excised tubal segments from 42 women with uterotubal junction obstruction were studied histologically to evaluate the pathologic spectrum of disease and correlate this with clinical data. The most frequent lesion encountered was obliterative fibrosis (38.1%), confirmed by connective tissue stains, which was not associated with cornual nodularity. Other pathologic entities included salpingitis isthmica nodosa (23.8%), intramucosal endometriosis (14.3%), and chronic tubal inflammation (21.4%). Intramucosal endometriosis was distinguishable from salpingitis isthmica nodosa by virtue of its unique stroma confirmed by connective tissue staining. Women with previous pregnancies were included in all the groups. In all instances, the obstruction was present in the transmural portion of the tube and extended a variable distance into the isthmic segment. These observations on uterotubal junction obstruction demonstrate that: 1) There are multiple distinct histologic patterns, 2) Intraabdominal findings do not predict the histology of the uterotubal junction pathology, 3) Any histologic pattern can be associated with a previous intrauterine or ectopic pregnancy, and 4) The obstruction begins within the transmural portion of the oviduct, extends a variable distance into the isthmic segment, but does not obstruct the ampullary segment. These data suggest that the initiating process originates within the uterus and that fibrosis may represent a nonspecific response to chronic injury of the transmural and isthmic segments of the oviduct.  相似文献   
76.
Management of a normal-appearing ovary at the time of hysterectomy in a patient with endometriosis externa is controversial. Our experience supports the contention that such ovaries should not be conserved at the time of surgery intended to cure endometriosis.  相似文献   
77.
Hemmerling TM  Fortier JD 《Anesthesia and analgesia》2002,95(2):322-3, table of contents
IMPLICATIONS: Falsely increased bispectral index (BIS) values of >70 occur during forced-warm-air therapy in patients undergoing cardiac surgery. When forced-warm-air therapy for the head is used (as in ultra-fast-tracking cardiac patients), BIS interpretation needs careful examination. Falsely increased BIS values can easily be recognized when the warm-air flow is stopped. Within 2-3 min, BIS returns to a much lower, "true" value.  相似文献   
78.
PURPOSE: To assess the influence of the family history (FH) of epilepsy or febrile seizures (FSs) on the clinical presentation of FSs and on their outcome. METHODS: We reviewed the charts of 482 children admitted to the Ste-Justine Hospital with FSs between 3 months and 6 years of age and followed for at least 5 years. RESULTS: Children with a positive FH of epilepsy (n=67) showed significantly more focal and recurrent FSs than those without such a FH. The risk of developing partial epilepsy (n=17) or generalized epilepsy (n=19) was significantly greater in children with focal or recurrent FSs, respectively. In children with focal FSs, only two out of 30 (6.7%) children with a negative FH of epilepsy developed partial epilepsy compared with four out of nine (44.4%) children with a positive FH. In children with recurrent FSs, as much as seven out of 34 (20.6%) children with a positive FH of epilepsy developed generalized epilepsy compared to only eight out of 161 (0.05%) of those with a negative FH. Nevertheless, when not taking into account the clinical presentation of FSs, the positive FH of epilepsy constituted a risk factor for developing generalized but not partial epilepsy. Finally, children with a positive FH of FSs (n=120) exhibited significantly more recurrent FSs than those without such a FH, but this did not modify the risk of epilepsy. CONCLUSION: The FH of FSs and/or epilepsy should be taken into account when evaluating the risk of FSs recurrence and of epilepsy.  相似文献   
79.
Very-low-birthweight (VLBW) neonates are more prone to complications and death than term infants are. In a 15-year period, 19 neonates with VLBW were operated on for necrotizing enterocolitis (NEC). Indications for operation were pneumoperitoneum in 12 and deterioration of general condition in 7. Bowel resection and intestinal diversion was performed in 12, a lateral enterostomy at the site of perforation was created in 5, and 2 neonates with necrosis of the whole bowel underwent an exploratory laparotomy without any further surgical treatment. Surgical complications were found in one-third of the patients. The mortality rate was significantly higher when the ileum was affected. The survival rate was 68%. Prior to 1984 the survival rate was 37% (3/8); subsequently, it has improved to 91% (10/11) as a result of improved intensive therapy.  相似文献   
80.
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