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   3952篇
  免费   218篇
  国内免费   24篇
耳鼻咽喉   132篇
儿科学   121篇
妇产科学   77篇
基础医学   530篇
口腔科学   182篇
临床医学   367篇
内科学   1043篇
皮肤病学   96篇
神经病学   250篇
特种医学   86篇
外科学   480篇
综合类   15篇
预防医学   120篇
眼科学   81篇
药学   315篇
中国医学   10篇
肿瘤学   289篇
  2022年   25篇
  2021年   64篇
  2020年   40篇
  2019年   58篇
  2018年   68篇
  2017年   57篇
  2016年   59篇
  2015年   64篇
  2014年   76篇
  2013年   106篇
  2012年   191篇
  2011年   153篇
  2010年   108篇
  2009年   99篇
  2008年   181篇
  2007年   150篇
  2006年   142篇
  2005年   155篇
  2004年   159篇
  2003年   160篇
  2002年   171篇
  2001年   156篇
  2000年   166篇
  1999年   154篇
  1998年   45篇
  1997年   46篇
  1996年   41篇
  1995年   35篇
  1994年   30篇
  1993年   30篇
  1992年   98篇
  1991年   76篇
  1990年   87篇
  1989年   102篇
  1988年   89篇
  1987年   101篇
  1986年   91篇
  1985年   72篇
  1984年   59篇
  1983年   44篇
  1979年   50篇
  1978年   26篇
  1977年   26篇
  1975年   19篇
  1974年   29篇
  1972年   20篇
  1970年   19篇
  1968年   19篇
  1967年   18篇
  1966年   24篇
排序方式: 共有4194条查询结果,搜索用时 2 毫秒
991.
992.
For decades, hyperbaric oxygen therapy has been considered a treatment option in patients with chronic radiation‐induced proctitis after pelvic radiation therapy. Refractory cases of chronic radiation‐induced proctitis include ulceration, stenosis, and intestinal fistulas with perforation. Appropriate treatment needs to be given. In the present study, we assessed the efficacy of hyperbaric oxygen therapy in five patients with radiation‐induced rectal ulcers. Significant improvement and complete ulcer resolution were observed in all treated patients; no side‐effects were reported. Hyperbaric oxygen therapy has a low toxicity profile and appears to be highly effective in patients with radiation‐induced rectal ulcers. However, hyperbaric oxygen therapy alone failed to improve telangiectasia and easy bleeding in four of the five patients; these patients were further treated with argon plasma coagulation (APC). Although hyperbaric oxygen therapy may be effective in healing patients with ulcers, it seems inadequate in cases with easy bleeding. Altogether, these data suggest that combination therapy with hyperbaric oxygen therapy and APC may be an effective and safe treatment strategy in patients with radiation‐induced rectal ulcers.  相似文献   
993.
Multiple sclerosis (MS), one of the most common chronic neurologic diseases, is characterized by the presence of multiple plaques of demyelination throughout the central nervous system. Although the etiology of the disease has not been established, it is believed to involve autoimmune mechanisms. We have examined sera from patients with MS for the presence of antibodies to antigens from brain and retina. Immunoblot analysis of soluble fraction of proteins from bovine brain revealed a prominent band at 45 kDa stained with sera of 8-14 patients with MS. In two patients with MS, serum antibody titers during relapse were higher compared with those when the patients were in remission. These antibodies were undetectable in cerebrospinal fluid of our MS patients and additionally were absent in sera of patients with other neurological diseases and normal control subjects. Furthermore, immunoblot analysis of the soluble fraction from bovine retinal rod outer segments revealed a prominent protein band at 48 kDa stained with MS sera. This antigen was purified to homogeneity from bovine retinal outer segments and identified as arrestin. Additionally, sera from MS patients reacted with purified beta-arrestin 1, a 45-kDa protein homologous to arrestin that is found in various tissues. Using limited proteolysis of arrestin and a competitive ELISA test with a synthetic peptide, we identified the recognition site(s) for antibodies in sera of MS patients at a dominant immunogenic site on arrestin located at the C-terminal region of the molecule. We suggest that the presence of circulating antibodies reactive with beta-arrestin or arrestin may be related to the course of MS progression.  相似文献   
994.
To examine the association of body mass index (BMI) and waist-to-hip ratio (WHR) with glucose intolerance among adults age 45 and over, we conducted a population-based study using an oral glucose tolerance test as a primary examination in two areas of Funagata, Japan, in 1990 and 1992. The number of eligible subjects was 1673. The participation rate was 84% (1408/1673). Glucose tolerance was assessed by the 1985 World Health Organization criteria as having diabetes (DM), impaired glucose tolerance (IGT), or normal glucose tolerance (NGT). Analyses by the generalized linear model revealed that both BMI and WHR were higher in the subjects with DM and IGT than those with NGT in both men and women after controlling for age. Analyses employing multiple logistic regression indicated that BMI and WHR were independently associated with IGT and DM in both men and women, except for BMI with IGT for men. The odds ratios for IGT associated with BMI were 1.06 (p=0.19) for men and 1.11 (p<0.01) for women. Those associated with WHR were 2.14 (p<0.01) for men and 1.35 (p<0.01) for women. These results imply that WHR plays an important role for developing DM independent of BMI.  相似文献   
995.
A 50-year-old woman was referred to our hospital for dysphagia and several episodes of esophageal food impaction during the prior three months. Complete blood count and basic biochemical tests were normal. No eosinophilia was found. Esophagogastroduodenoscopy (EGD) revealed the presence of concentric rings (esophageal “trachealization”) and stenosis along the middle and distal esophagus. Endoscopic ultrasound (EUS) showed circumferential thickening of all layers in the same part. Cytopathologic evaluation of a specimen obtained by endoscopic biopsy of the thickened area in the distal esophagus showed eosinophilic infiltration (20 eosinophils per high-powered field). She was diagnosed as having eosinophilic esophagitis (EoE). Topical steroid therapy was started. A tendency of dysphagia for relief and improvement of characteristic EGD findings began early, but wall thickening in EUS remained. Past reports of the related literature have described that thickness of submucosa and muscularis propria remained after therapy, although significant reduction in the mucosal thickness was provided by short-term steroid therapy. One explanation for early relapse is insufficient reduction in the submucosa and muscularis propria. Consequently, our patient was given steroids until thickness on EUS improved. EUS is regarded as useful for evaluating the curative effect in patients with EoE.  相似文献   
996.
AIM:To investigate the risk factors for delayed bleeding following endoscopic submucosal dissection(ESD)treatment for colorectal neoplasms.METHODS:We retrospectively reviewed the medical records of 317 consecutive patients with 325 lesions who underwent ESD for superficial colorectal neoplasms at our hospital from January 2009 to June2013.Delayed post-ESD bleeding was defined as bleeding that resulted in overt hematochezia 6 h to 30d after ESD and the observation of bleeding spots as confirmed by repeat colonoscopy or a required blood transfusion.We analyzed the relationship between risk factors for delayed bleeding following ESD and the following factors using univariate and multivariate analyses:age,gender,presence of comorbidities,use of antithrombotic drugs,use of intravenous heparin,resected specimen size,lesion size,lesion location,lesion morphology,lesion histology,the device used,procedure time,and the presence of significant bleeding during ESD.RESULTS:Delayed post-ESD bleeding was found in14 lesions from 14 patients(4.3%of all specimens,4.4%patients).Patients with episodes of delayed postESD bleeding had a mean hemoglobin decrease of2.35 g/dL.All episodes were treated successfully using endoscopic hemostatic clips.Emergency surgery was not required in any of the cases.Blood transfusion was needed in 1 patient(0.3%).Univariate analysis revealed that lesions located in the cecum(P=0.012)and the presence of significant bleeding during ESD(P=0.024)were significantly associated with delayed post-ESD bleeding.The risk of delayed bleeding was higher for larger lesion sizes,but this trend was not statistically significant.Multivariate analysis revealed that lesions located in the cecum(OR=7.26,95%CI:1.99-26.55,P=0.003)and the presence of significant bleeding during ESD(OR=16.41,95%CI:2.60-103.68,P=0.003)were independent risk factors for delayed post-ESD bleeding.CONCLUSION:Location in the cecum and significant bleeding during ESD predispose patients to delayed post-procedural bleeding.Therefore,careful and additional management is recommended for these patients.  相似文献   
997.
AIM: To compare therapeutic outcomes and adverse events in initial solitary hepatocellular carcinoma (HCC) treated with radiofrequency ablation (RFA) and CyberKnife®.METHODS: Seventy three consecutive patients with initial solitary HCC treated with RFA (38 patients; RFA group) and CyberKnife® (35 patients; CK group) were enrolled in this study. Background factors were compared between the two groups. Local and intrahepatic distant recurrence control, and cumulative survival rates were compared between the two groups. These were determined using the Kaplan-Meier method, and the significance of differences was analyzed by log-rank test. The presence of more grade 3 on CTCAE ver. 4.0 early and late adverse events was investigated.RESULTS: In background factors, age was significantly higher (P = 0.005) and the tumor diameter was significantly larger (P = 0.001) in the CK group. The 1-year local recurrence control rates were 97.4% and 97.1% in the RFA and CK groups, respectively (P = 0.71); the 1-year intrahepatic distant recurrence control rates were 85.6% and 86.1%, respectively (P = 0.91); and the 1-year cumulative survival rates were 100% and 95.2%, respectively (P = 0.075), showing no significant difference in any rate between the two groups. There were no late adverse event in the RFA group, but 11.4% in the CK group had late adverse events. In the CK group, the Child-Pugh score at 12 mo after treatment was significantly higher than that in the RFA group (P = 0.003) and significantly higher than the score before treatment (P = 0.034).CONCLUSION: The occurrence of adverse events is a concern, but CyberKnife® treatment is likely to become an important option for local treatment of early HCC.  相似文献   
998.
999.
1000.
We carried out a retrospective questionnaire survey of 792 submucosal colorectal carcinoma (CRC) cases from 15 institutions affiliated with the Colorectal Endoscopic Resection Standardization Implementation Working Group in Japanese Society for Cancer of the Colon and Rectum. In these cases, endoscopic resection (ER) and surveillance was carried out without additional surgical resection. Local recurrence or metastasis was observed in 18 cases. Local submucosal recurrence was observed in 11 cases, and metastatic recurrence was observed in 13 cases. Among the 15 cases in which the depth of submucosal invasion was measured, two cases showed depth less than 1000 µm, which has other risk factors for metastasis. Metastatic recurrence was observed in the lung, liver, lymph node, bone, adrenal glands, and the brain; in some cases, metastatic recurrence was observed in multiple organs. Death due to primary disease was observed in six cases. The average interval between ER and recurrence was 19.7 ± 9.2 months. In 16 cases, recurrence was observed within 3 years after ER. Thus, validity of ER without additional surgical resection for cases with the conditions that the depth of submucosal invasion is less than 1000 µm and the histological grade is well or moderately differentiated adenocarcinoma with no lymphatic and venous involvement was proven.  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