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   2276篇
  免费   147篇
  国内免费   18篇
耳鼻咽喉   32篇
儿科学   76篇
妇产科学   62篇
基础医学   227篇
口腔科学   61篇
临床医学   228篇
内科学   523篇
皮肤病学   64篇
神经病学   138篇
特种医学   45篇
外科学   424篇
综合类   66篇
一般理论   4篇
预防医学   126篇
眼科学   91篇
药学   132篇
中国医学   22篇
肿瘤学   120篇
  2024年   4篇
  2023年   39篇
  2022年   76篇
  2021年   103篇
  2020年   64篇
  2019年   88篇
  2018年   91篇
  2017年   76篇
  2016年   79篇
  2015年   63篇
  2014年   112篇
  2013年   104篇
  2012年   203篇
  2011年   182篇
  2010年   106篇
  2009年   86篇
  2008年   132篇
  2007年   110篇
  2006年   121篇
  2005年   106篇
  2004年   76篇
  2003年   79篇
  2002年   60篇
  2001年   29篇
  2000年   29篇
  1999年   26篇
  1998年   12篇
  1997年   10篇
  1996年   11篇
  1995年   10篇
  1994年   5篇
  1992年   20篇
  1991年   12篇
  1990年   15篇
  1989年   12篇
  1988年   10篇
  1987年   9篇
  1986年   15篇
  1985年   4篇
  1979年   5篇
  1978年   3篇
  1976年   3篇
  1974年   2篇
  1972年   2篇
  1971年   2篇
  1970年   4篇
  1969年   6篇
  1968年   2篇
  1966年   5篇
  1918年   2篇
排序方式: 共有2441条查询结果,搜索用时 15 毫秒
1.
2.
Abdominal Radiology - Metastatic involvement of the ovaries is not rare. The most common tumor types metastasizing to the ovaries, from non-gynecological organs, are breast, colorectal, gastric,...  相似文献   
3.
Acute generalized exanthematous pustulosis (AGEP) is seen uncommonly in children and sometimes shows atypical clinical features in this population. Patch testing can be used effectively in children for the confirmation of the culprit drug in cases of multiple drug use. Here, we report a rare, pediatric case of ceftriaxone‐induced AGEP confirmed by patch testing with subsequent recurrence of the skin eruption.  相似文献   
4.
This study evaluated the performance of a synthetic implant material, Hard Tissue Replacement Polymer, for: (1) ease of handling, (2) compatibility with bone and soft tissue, (3) stability of augmentation over time, and (4) development of untoward effects. HTR (a registered trademark of HTR Sciences, a division of United States Surgical Corporation, Norwalk, CT 06856) was implanted into 34 patients by means of five different surgical procedures. The material was found to be easy to manipulate during surgery. Tissue and bone compatibility, defined as absence of inflammation, was present in 32/34 surgical sites (94%). In extraction sites during the 18-month follow-up, no measurable decrease in bone height or width was seen. One patient with a large periodontal endodontic defect developed a post-operative infection necessitating extraction of the tooth. No induction of bone was seen in response to placement of HTR material.  相似文献   
5.
Forty-three patients with neonatal tetanus admitted to the Infectious Diseases Ward of the Istanbul University Faculty of Medicine Children's Hospital at Capa from 1982-1989 are presented. Thirty-two (74.4%) of the subjects were boys. The overall mortality was found to be 60 percent and the mean incubation period 6.1 +/- 20 days. The mean period between onset of symptoms and hospital admission was 1.7 days. Thirty-nine (90.7%) of the 43 patients were unhygienic home deliveries and only two cases were delivered with a midwife in attendance. None of the mothers of the children in our series had been immunized with tetanus toxoid. The incidence of neonatal tetanus in Turkey is on the decline, but a fraction of the population, the so-called urban poor, is still at high risk for preventable diseases. Every contact an unvaccinated person has with a health care professional should be viewed as an opportunity for tetanus immunization.  相似文献   
6.
The role of surgery in intraabdominal Burkitt's lymphoma remains controversial and different opinions are present in the literature. In our institution, forty patients (30 boys and 10 girls) with intraabdominal Burkitt's lymphoma with ages ranging from 3 to 12 years have been treated and followed from 1989 through 2000. In ten cases, the patients underwent surgery because of their acute abdominal diseases (intestinal obstruction in 5, intussusception in 3, intestinal perforation in one, and acute appendicitis in one). The remaining thirty patients were referred to our clinic because of their abdominal masses, pain, anorexia and fatigue. Twelve children had localized tumors and total resection could be performed. There was one death in this group due to central nervous system involvement during chemotherapy. In the remaining 28 children, extensive intraabdominal diseases were detected. In four of them, debulking procedures were performed, while in 24 children only biopsies could be made; 8 of them underwent a second-look operation. In the debulking procedures group, two children were lost (50 %) due to tumorlysis and acute renal failure. In the biopsy group, there were six deaths (25 %). All patients received chemotherapy after operative recovery. In conclusion, our results suggest that when the tumor is localized, total resection results in a good outcome. However, in the presence of extensive intraabdominal diseases instead of resection, the operation should be limited to biopsy only.  相似文献   
7.
Primary hydatid disease of the intestinal mesentery is rare. We report on a 12-year-old male patient who presented with abdominal pain and urticaria lesions after blunt abdominal trauma. At laparotomy the cyst was found to be ruptured and was totally removed from the surrounding mesenteric tissue.The postoperative course was uneventful. This case is the first child reported with traumatic rupture of a hydatid cyst in a mesenteric location.  相似文献   
8.
Hepatitis E virus (HEV) is the causative agent of hepatitis E, anacute form of viral hepatitis. The open reading frame 2 (ORF2) of HEV encodes the viral capsid protein, which can self-oligomerize into virus-like particles. To understand the domains within this protein important for capsid biogenesis, we have carried out in vitro analyses of association and folding patterns of wild type and mutant ORF2 proteins. When expressed in vitro or in transfected cells, the ORF2protein assembled as dimers, trimers and higher order forms. WhileN-terminal deletions up to 111 amino acids had no effect, the deletion of amino acids 585–610 led to reduced homo-oligomerization. This deletion also resulted in aberrant folding of the protein, as determined by its sensitivity to trypsin. This study suggests that a C-terminal hydrophobic region encompassing amino acids 585–610 of the ORF2 protein might be critical for capsid biogenesis.  相似文献   
9.
10.

Background

Several investigations have studied gait variability of individuals with anterior cruciate ligament (ACL) deficiency; however, the effect of dual-tasking on the gait variability of these individuals remained unclear. The aim of the present study was to determine the effect of gait speed and dual-tasking on knee flexion–extension variability in subjects with and without ACL deficiency.

Methods

The knee flexion–extension Lyapunov exponent (LyE) was measured in 22 ACL-deficient (Mean±SD) (25.95?±?4.69?years) and 22 healthy subjects (24.18?±?3.32?years). They walked at three levels of gait speed in isolation or concurrently with a cognitive task.

Results

Repeated-measure analyses of variance (ANOVAs) demonstrated that the interaction of group by gait speed was statistically significant. As the gait speed increased from low to high, the knee flexion–extension LyE significantly decreased for the subjects with ACL deficiency (effect size: 0.57, P?=?0.01). The interaction of group by cognitive load was not statistically significant (P?=?0.07). In addition, the ACL-deficient subjects had statistically slower reaction times than healthy subjects during the dual-task compared with the single-task condition.

Conclusions

The ACL-deficient and healthy individuals had a tendency to maintain safe gait. It seems that the ACL-deficient subjects sacrificed the cognitive task more than the healthy individuals to pay more attention toward gait. Additionally, it seems that the gait speed was more challenging than cognitive load on the stride-to-stride variability in the individuals with ACL deficiency.  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