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   1945篇
  免费   102篇
  国内免费   3篇
耳鼻咽喉   23篇
儿科学   53篇
妇产科学   119篇
基础医学   240篇
口腔科学   72篇
临床医学   179篇
内科学   432篇
皮肤病学   15篇
神经病学   75篇
特种医学   49篇
外科学   379篇
综合类   25篇
预防医学   89篇
眼科学   30篇
药学   152篇
中国医学   6篇
肿瘤学   112篇
  2023年   43篇
  2022年   79篇
  2021年   103篇
  2020年   49篇
  2019年   70篇
  2018年   94篇
  2017年   63篇
  2016年   65篇
  2015年   45篇
  2014年   67篇
  2013年   81篇
  2012年   146篇
  2011年   163篇
  2010年   91篇
  2009年   62篇
  2008年   98篇
  2007年   89篇
  2006年   90篇
  2005年   105篇
  2004年   83篇
  2003年   61篇
  2002年   53篇
  2001年   19篇
  2000年   17篇
  1999年   24篇
  1998年   12篇
  1997年   8篇
  1996年   11篇
  1995年   5篇
  1993年   6篇
  1992年   13篇
  1991年   11篇
  1990年   15篇
  1989年   14篇
  1988年   10篇
  1987年   12篇
  1986年   5篇
  1985年   9篇
  1984年   7篇
  1983年   6篇
  1982年   4篇
  1981年   3篇
  1980年   3篇
  1979年   3篇
  1973年   3篇
  1972年   3篇
  1970年   4篇
  1969年   2篇
  1967年   6篇
  1966年   2篇
排序方式: 共有2050条查询结果,搜索用时 11 毫秒
991.
992.
Diaphragmatic hernias (DH) occurring after pediatric liver transplantation (LT) are rare. However, such complications have been previously reported in the literature and treatment has always been surgical repair via laparotomy. We report our experience of minimally invasive thoracoscopic approach for repair of DH occurring after LT in pediatric recipients.From April 2010 to December 2014, 7 cases of DH were identified in pediatric LT recipient in Samsung Medical Center. Thoracoscopic repair was attempted in 3 patients. Patients’ medical records were retrospectively reviewed.Case 1 was a 12-month-old boy, having received deceased donor LT for biliary atresia (BA) 5 months ago. He presented with dyspnea and left-sided DH was detected. Thoracoscopic repair was successfully done and the boy was discharged at postoperative day 7. Case 2 was a 13-month-old boy, having received deceased donor LT for BA 2 months ago. He presented with vomiting and right-sided DH was detected. Thoracoscopic repair was done along with primary repair of herniated small bowel that was perforated while attempting reduction into the peritoneal cavity. The boy recovered from the surgery without complications and was discharged on the 10th postoperative day. Case 3 was a 43-month-old girl, having received deceased donor LT for Alagille syndrome 28 months ago. She was diagnosed with right-sided DH during steroid pulse therapy for acute rejection. Thoracoscopic repair was attempted but a segment of necrotic bowel was noticed along with bile colored pleural effusion and severe adhesion in the thoracic cavity. She received DH repair with small bowel resection and anastomosis via laparotomy.Thoracoscopic repair was attempted in 3 cases of DH occurring after LT in pediatric recipients. With experience and expertise in pediatric minimally invasive surgery, thoracoscopic approach is feasible in this rare population of patients.  相似文献   
993.
994.
Lambda‐cyhalothrin (LCT) is a widely used broad‐spectrum pyrethroid insecticide. Oral LCT administration to adult male mice at 3 doses (0.2, 0.4, and 0.8 mg/kg/day) for 6 weeks caused a significant reduction in the weight of the seminal vesicles. The epididymal sperm count was lower in mice that received at the highest dose than in control mice. However, the proportions of live and motile spermatozoa were reduced at both the medium and the high doses compared with control mice. All doses induced an increase in the number of morphologically abnormal spermatozoa. Histopathological observations of the testes, liver, kidneys, and spleen showed dose‐related degenerative damage in LCT‐treated mice. The results indicate that LCT has reproductive toxicity, hepatotoxicity, nephrotoxicity, and splenotoxicity in male mice at the tested doses. © 2012 Wiley Periodicals, Inc. Environ Toxicol 29: 750–762, 2014.  相似文献   
995.
996.
997.
998.
The efficacy of helical CT in the diagnosis of small bowel obstruction   总被引:4,自引:0,他引:4  
OBJECTIVE: To evaluate the usefulness and reliability of helical computed tomography (CT) for patients with small bowel obstruction. METHODS AND MATERIAL: Helical CT findings of 41 patients were evaluated prospectively on the basis of the presence and the cause of obstruction, and the presence of strangulation. RESULTS: In the determination of the cause of the obstruction sensitivity and specificity of CT were 84 and 90%, respectively. Of the 19 patients undergoing surgery, 6 had strangulation and were correctly identified by CT. CONCLUSION: Helical CT is an accurate method in the detection of small bowel obstruction, especially for evaluating the cause and vascular complications of obstruction.  相似文献   
999.
BACKGROUND: DISC-HSV is a replication incompetent herpes simplex virus that is a highly efficient vector for the transduction of genes in vivo and in vitro. We examine the ability of DISC-HSV to infect human prostate cancer cell-lines and xenograft tumor models, and induce expression of reporter and therapeutic cytokine genes. METHODS: Infection was confirmed by cellular staining for the beta-galactosidase reporter gene product, and by EM. Human GM-CSF production following DISC-hGMCSF infection was measured using ELISA. The metabolic activity of infected cells was determined by NADP/NADPH assay. Cell death was estimated by cell-cycle analysis using flow cytometry with propidium iodide staining. RESULTS: Infection of DU145, PC3 and LNCaP cells with DISC-HSV was dose dependent. Cells infected with DISC-hGM-CSF released significant levels of hGM-CSF for 3 days. NADP/NADPH assay suggested that infected cells continued to be metabolically active for 3 days post-infection, which was consistent with flow cytometry findings that cell death did not occur within 7 days of infection. Tumor xenografts injected with DISC-HSV expressed beta-galactosidase, and intracellular viral particles were demonstrated using EM. CONCLUSIONS: We have previously reported the rejection of established tumors following intra-tumoral injection of DISC-GMCSF. This study demonstrates the ability of DISC-HSV to infect prostate cancer and express GMCSF at significant levels. We suggest that prostate cancer is a potential target for therapy using DISC-HSV containing GM-CSF.  相似文献   
1000.
BACKGROUND: Tissue inhibitors of metalloproteinases (TIMPs) play a major role in extracellular matrix turnover in the lung. However, in chronic lung disorders such as idiopathic pulmonary fibrosis (IPF) and pigeon breeders' disease (PBD), TIMPs may promote an adverse non-degradative environment. We hypothesised that polymorphisms in TIMP-3 could affect susceptibility to IPF and PBD. METHODS: Two promoter variants, -915A>G and -1296T>C, were genotyped in 323 healthy subjects, 94 subjects with IPF, 115 with PBD, and 90 exposed to avian antigen but without PBD. The severity of fibrosis in lung tissue and the clinical outcome after 1 year was determined in the PBD group. RESULTS: The variants did not influence susceptibility to IPF, but the rare alleles of both variants appeared to be protective against susceptibility to PBD (odds ratio (OR) for carriage of at least one rare allele from either variant 0.48, 95% CI 0.30 to 0.76, p = 0.002). Haplotype analysis of positions -915 and -1296 estimated four haplotypes: *A*T, *G*T, *A*C and *G*C, respectively. Their frequencies differed overall between subjects with PBD and healthy subjects (p = 0.0049) and this was attributable primarily to the *G*C haplotype (OR 0.53, 95% CI 0.36 to 0.77, p = 0.001). The severity of fibrosis correlated with poorer outcome in the PBD group (r = 0.73, p<0.01) but no relationship was seen between the *G*C haplotype and outcome or fibrosis. However, PBD subjects with the *G*C haplotype did have proportionally fewer lymphocytes in their bronchoalveolar fluid than those with the common *A*T haplotype (p = 0.029). CONCLUSIONS: TIMP-3 variants appear to contribute to susceptibility to PBD. This may be through the inflammatory reaction rather than the fibrotic reaction.  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