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   16811篇
  免费   838篇
  国内免费   152篇
耳鼻咽喉   173篇
儿科学   430篇
妇产科学   138篇
基础医学   1998篇
口腔科学   391篇
临床医学   1037篇
内科学   4612篇
皮肤病学   303篇
神经病学   1112篇
特种医学   758篇
外科学   2887篇
综合类   56篇
预防医学   375篇
眼科学   190篇
药学   1040篇
中国医学   29篇
肿瘤学   2272篇
  2023年   137篇
  2022年   250篇
  2021年   504篇
  2020年   276篇
  2019年   321篇
  2018年   430篇
  2017年   337篇
  2016年   417篇
  2015年   422篇
  2014年   528篇
  2013年   712篇
  2012年   1049篇
  2011年   1206篇
  2010年   649篇
  2009年   555篇
  2008年   1019篇
  2007年   1174篇
  2006年   1043篇
  2005年   1087篇
  2004年   1090篇
  2003年   1006篇
  2002年   1015篇
  2001年   200篇
  2000年   165篇
  1999年   182篇
  1998年   267篇
  1997年   195篇
  1996年   181篇
  1995年   169篇
  1994年   167篇
  1993年   166篇
  1992年   94篇
  1991年   98篇
  1990年   80篇
  1989年   73篇
  1988年   57篇
  1987年   52篇
  1986年   42篇
  1985年   37篇
  1984年   30篇
  1983年   33篇
  1982年   44篇
  1981年   31篇
  1980年   29篇
  1979年   14篇
  1978年   28篇
  1977年   15篇
  1976年   17篇
  1974年   21篇
  1973年   13篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
221.
222.
The Asian variant of intravascular large B cell lymphoma is a special type of intravascular lymphoma with hemophagocytic syndrome and hypercytokinemia including interleukin-6, which stimulates antidiuretic hormone synthesis in the hypothalamus. We present here that the syndrome of inappropriate antidiuretic hormone secretion frequently occurs in patients with the Asian variant of intravascular large B cell lymphoma. The syndrome of inappropriate antidiuretic hormone secretion was found in eight of 118 (6.8%) lymphoma patients at the first diagnosis. Although there were six (5.1%) among 118 lymphoma patients with the Asian variant of intravascular large B cell lymphoma, four of the six patients (66.7%) developed the syndrome of inappropriate antidiuretic hormone secretion. In four patients with the Asian variant of intravascular large B cell lymphoma with the syndrome of inappropriate antidiuretic hormone secretion, elevated serum interleukin-6 and low sodium levels were almost normalized after chemotherapy. The Asian variant of intravascular large B cell lymphoma patients frequently develop the syndrome of inappropriate antidiuretic hormone secretion, and interleukin-6 might play a role in the occurrence of this disease. We should pay attention to hyponatremia caused by the syndrome of inappropriate antidiuretic hormone secretion in patients with the Asian variant of intravascular large B cell lymphoma.  相似文献   
223.
The present patient developed a severe rectal ulcer more than 1 month after having received external beam radiation therapy for prostate cancer. Surveillance endoscopy every 3 months demonstrated healing of this rectal ulcer using a novel therapy. He was given enemas with ecabet sodium, which provides physical protection and promotes healing by increasing prostaglandin E2, and this process induced squamous metaplasia that halted the progression of the ulcer of radiation proctitis as a late‐phase reaction. Intrapapillary capillary loops were visualized with magnified narrow band imaging at the healing ulcer site as seen via the esophagus and, moreover, demonstrated histologically.  相似文献   
224.
225.
BACKGROUND: Although the anti-atherosclerotic effects of HMG-CoA reductase inhibitors are well known, their specific effect on saphenous vein grafts after coronary artery bypass graft (CABG) operation is not well documented and has not been studied in Japan, so the aim of the present prospective randomized controlled study involving 27 Japanese institutions was to investigate the effects of pravastatin on the progression of atherosclerosis in such grafts and native coronary arteries after CABG. METHODS AND RESULTS: A total of 303 patients who had undergone CABG were randomly assigned to either the pravastatin group (n =168) or the control group (n = 167). Paired coronary angiograms were obtained at baseline and at the end of 5-year follow-up in 182 (60%) patients. The low-density lipoprotein cholesterol concentration significantly decreased in the pravastatin group from 141.4 mg/dl to 113.7 mg/dl (-19.6%), compared with 141.1 mg/dl to 133.7 mg/dl (-5.2%) in the control group (p < 0.001). Although there was no significant difference in the quantitative coronary angiography measurements between the 2 groups, the global change score indicated a significant pravastatin-mediated reduction in plaque progression (p < 0.01). CONCLUSIONS: Pravastatin can potentially reduce atherosclerotic progression in both the bypass graft and native coronary arteries of patients after CABG.  相似文献   
226.
BACKGROUND/AIMS: Helicobacter pylori infection is known to induce gastritis, oxidative stress, and cyclooxygenase (COX)-2 expression in the gastric mucosa. However, the effect of H. pylori infection on remnant gastritis has not been studied. We investigated whether the severity of remnant gastritis and COX-2 expression were affected by H. pylori infection after distal gastrectomy. METHODOLOGY: The study included 97 patients with gastric cancer who underwent curative distal gastrectomy with lymphadenectomy in our department between May 1999 and April 2001. All patients underwent endoscopic examination 2 weeks before and 12 weeks after surgery. The presence of H. pylori infection was determined by urease activity, hematoxylin-eosin staining, and immunochemical staining. Histologic remnant gastritis was graded based on the degree of neutrophil infiltration using the updated Sydney System. COX-2 expression was estimated immunohistochemically. RESULTS: Both the degree of neutrophil infiltration and the level of COX-2 expression were significantly higher in patients with than without H. pylori (p<0.05). There was a significant correlation between the degree of neutrophil infiltration and the degree of COX-2 expression (p<0.001). CONCLUSIONS: H. pylori eradication may become a treatment for preventing both remnant gastritis as well as remnant gastric carcinoma after distal gastrectomy.  相似文献   
227.
228.
BACKGROUND: Endoscopic submucosal dissection (ESD) of early gastric cancer is less invasive than surgical resection, and if technically feasible, it may result in less long-term morbidity than does incisional surgery. However, ESD is technically difficult in patients who have had a previous distal gastrectomy. OBJECTIVE: Our purpose was to retrospectively assess the results of ESD of early gastric cancer in the remnant stomach. DESIGN: Case series. SETTING AND PATIENTS: A total of 31 lesions in 30 patients with early remnant gastric cancer were treated with ESD at Okayama University Hospital, Tsuyama Central Hospital, Hiroshima City Hospital, Kagawa Prefectural Central Hospital, and Mitoyo General Hospital from March 2001 to January 2007. INTERVENTION: ESD. MAIN OUTCOME MEASUREMENTS: En bloc resection rate, complete resection rate, operation time, and complications. RESULTS: En bloc resection and complete resection were achieved in 30 (97%) and in 23 (74%) lesions, respectively. The median operation time required for ESD in the remnant stomach was 113 minutes (range 45-450 minutes). Perforation occurred in 4 (13%). The incidence of delayed bleeding requiring blood transfusion was 0%. LIMITATION: Short duration of follow-up. CONCLUSIONS: ESD is feasible in the remnant stomach but has a relatively high complication rate and should only be performed by experienced endoscopists.  相似文献   
229.
230.
Effects of HMGB1 on ischemia-reperfusion injury in the rat heart   总被引:1,自引:0,他引:1  
BACKGROUND: Coronary ischemia-reperfusion (I/R) injury causes cardiomyocyte necrosis in a multi-step process that includes an inflammatory reaction. A recent study has suggested that high-mobility group box 1 (HMGB1) is a late mediator of lethal sepsis and an early mediator of inflammation and necrosis following I/R injury. In the present study a neutralizing monoclonal antibody (mAb) for HMGB1 was used to clarify the role of HMGB1 in cardiac I/R injury. METHODS AND RESULTS: Rats underwent 30 min of left coronary artery occlusion followed by 60 min reperfusion. An intravenous injection of anti-HMGB1 mAb or control IgG was administered just before reperfusion. The infarct size was enlarged in the anti-HMGB1 mAb group in comparison with the control group (p<0.05). The treatment of anti-HMGB1 mAb significantly increased the plasma troponin-T and norepinephrine (NE) content in the heart in comparison with the control (p<0.05). Moreover, the production of dihydroxyphenylglycol was reduced in the anti-HMGB1-treated group (p<0.05). CONCLUSION: This study shows for the first time the effects of treatment with neutralizing anti-HMGB1 mAb on I/R injury in the rat heart. The findings support the novel view that I/R-induced HMGB1 may be an important factor in the modulation of interstitial NE.  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