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   6448篇
  免费   299篇
  国内免费   35篇
耳鼻咽喉   73篇
儿科学   144篇
妇产科学   70篇
基础医学   760篇
口腔科学   218篇
临床医学   497篇
内科学   1836篇
皮肤病学   84篇
神经病学   484篇
特种医学   173篇
外科学   1181篇
综合类   39篇
预防医学   179篇
眼科学   57篇
药学   369篇
中国医学   17篇
肿瘤学   601篇
  2023年   46篇
  2022年   113篇
  2021年   209篇
  2020年   97篇
  2019年   130篇
  2018年   168篇
  2017年   126篇
  2016年   135篇
  2015年   111篇
  2014年   169篇
  2013年   215篇
  2012年   314篇
  2011年   361篇
  2010年   183篇
  2009年   139篇
  2008年   285篇
  2007年   293篇
  2006年   277篇
  2005年   314篇
  2004年   299篇
  2003年   274篇
  2002年   314篇
  2001年   197篇
  2000年   188篇
  1999年   165篇
  1998年   92篇
  1997年   51篇
  1996年   57篇
  1995年   43篇
  1994年   39篇
  1993年   37篇
  1992年   129篇
  1991年   102篇
  1990年   88篇
  1989年   120篇
  1988年   111篇
  1987年   83篇
  1986年   100篇
  1985年   101篇
  1984年   49篇
  1983年   53篇
  1982年   25篇
  1981年   26篇
  1980年   26篇
  1979年   51篇
  1978年   33篇
  1976年   22篇
  1973年   27篇
  1972年   21篇
  1969年   22篇
排序方式: 共有6782条查询结果,搜索用时 0 毫秒
1.
The association of bone with the metabolic syndrome and its features, visceral fat accumulation or insulin resistance, remains unclear. We determined visceral and subcutaneous fat areas (V and S) by computed tomography on 187 men (28–83 years) and 125 postmenopausal women (46–82 years) with type 2 diabetes. Men whose V was 100 cm2 or more had significantly lower urinary N-terminal cross-linked telopeptide of type-I collagen (p = 0.005), higher femoral neck bone mineral density (FN-BMD) (p = 0.004), and lower prevalence of vertebral fractures (VFs) (p = 0.04) than controls. Fat mass, V, S, and lean body mass positively correlated with FN-BMD in men and with lumbar (L) and FN-BMD in women. When adjusted for weight, these correlations became negative. Urinary C-peptide positively correlated with FN-BMD in both genders. Multivariate logistic regression analysis adjusted for age, height, weight, L-BMD, duration of diabetes, and diabetes therapies identified V in men and urinary C-peptide in women as factors inversely associated with the presence of VFs [odds ratio (OR) = 0.61 per SD increase, p = 0.04, and OR = 0.32, p = 0.01, respectively]. These findings suggest that, of the components of the metabolic syndrome, body fat in gravity and hyperinsulinemia could increase FN-BMD in diabetic subjects. Visceral fat in men and hyperinsulinemia in women may protect against VFs independent of weight, L-BMD, diabetes duration, or therapies.  相似文献   
2.
Effects of human recombinant TNF on the tumor blood vessels and on the thrombus formation were investigated in relation to its mode of antitumor action against Meth-A sarcoma transplanted in BALB/c mice. The extent of the blood vessel lesion was evaluated by using transparent chamber placed in the mouse skin. Bleeding, hyperemia and congestion were observed at 1-2h, 4-6h and 24h after TNF (1 X 10(4)U/mouse) administration, respectively. In contrast, no histological changes in the normal blood vessels were observed microscopically following TNF injection. Thrombus formation was evoked in the tumor vessels 4h after TNF injection. However, when thrombus formation was prevented by heparin, no difference was observed among antitumor action of TNF against Meth-A fibrosarcoma necrotic response and the rate of complete cure. These results suggest that the direct effects of TNF causing lesions in the tumor blood vessels plays an important role in its antitumor action.  相似文献   
3.
4.
Symptomatic liver cyst: Special reference to surgical management   总被引:2,自引:0,他引:2  
We conducted a retrospective study of 14 patients with symptomatic liver cysts to evaluate current therapeutic interventions for this condition. Abdominal pain (n = 7) or abdominal mass (n = 5) were the most frequent presentations. Three patients also had renal cyst. Percutaneous aspiration with ethanol sclerotheraphy was carried out in 4 patients and all cysts so treated diminished in size, with relief of the symptoms. One patient was treated by aspiration only and re-retension occurred. Cystectomy was performed in 2 patients, unroofing in 5, and fenestration in 2 patients. All patients gained relief of symptoms, with no recurrence of symptoms. Computed tomography revealed that the cysts were diminished or were no longer observable after all the treatments. Our experience indicates that unroofing, fenestration, and cystectomy are safe and suitable procedures for treatment of the condition. Ethanol sclerotherapy may be a feasible alternative to surgical intervention in selected patients. Received for publication on July 23, 1997; accepted on Dec. 25, 1997  相似文献   
5.
In this study, the effect of combining anti-CD4 monoclonal antibody (mAb) and cyclosporin (CyA) therapy at the time of transplantation was examined. A mouse cardiac allograft model was used. Anti-CD4 mAb administered perioperatively induces long-term survival. The addition of a short course of CyA given subcutaneously in a regimen of either a high-dose treatment or a standard dose treatment to the anti-CD4 mAb treatment protocol did not have a detrimental effect on graft survival. Despite having no significant effect on graft survival, the addition of CyA to the treatment protocol did result in a significant decrease in the level of IL-2 present in the hearts 7 days after transplantation. The decrease in IL-2 production was directly related to the presence of CyA in vivo. When CyA treatment was continued throughout the period during which unresponsiveness to the graft is induced by anti-CD4 mAb therapy, 50 % of the grafted hearts were rejected once the CyA was discontinued. In conclusion, the combined use of anti-CD4 mAb therapy and CyA did not have a negative effect on graft survival in this model when the two agents were used concurrently at the time of transplantation. Received: 2 October 1996 Received after revision: 31 January 1997 Accepted: 5 February 1997  相似文献   
6.
Intralobar pulmonary sequestration associated with asymptomatic aspergillosis is a rare case. We describe the case of a 65-year-old woman with intrapulmonary sequestration, anomalous systemic arterial supply to the left lower lobe and aspergillosis who underwent left lower lobectomy and ligation of an anomalous artery by Video-Assisted Thoracoscopic surgery (VATS). Pathological examination showed the parenchymal distortion and chronic inflammation. Aspergillus were found in the cyst. VATS lobectomy for intralobar pulmonary sequestration is a safe and valid procedure.  相似文献   
7.
8.
Bismuth subnitrate (BSN), a bismuth compound medically used for antidiarrheics, was orally administered to see whether it can reduce CDDP nephrotoxicity or not. Thirteen patients aged 19 approximately 60 with ovarian cancer entered this BSN-CDDP trial. A total of thirty three courses of BSN-CDDP treatment was undergone. BSN was administered orally at a dose of 50 mg/kg for five days before CDDP therapy. CDDP was infused for two hours. No vigorous hydration or diuresis was performed. Only 2,000 ml of saline with 20 mEq per liter of KCl was given for post-hydration. The median dose of CDDP was 100 mg/m2. The renal toxicity of BSN-CDDP treatment was minimum. 82% of the courses at the sixth day after the treatment had creatinine clearance levels which were more than 80% of those before the treatment. But twenty-four hour NAG and beta 2-microglobulin excretion were significantly increased. Bone marrow suppression and gastrointestinal disturbance were commonly observed. The results of our study indicate that BSN pretreatment reduces the renal toxicity of CDDP to some extent.  相似文献   
9.
The findings in twenty-two patients with insulinoma were reviewed, as continuous efforts should be made to establish preoperative localization of the tumor. Superselective arteriography and percutaneous, transhepatic portal vein and pancreatic venous catheterization are highly recommended approaches. At the time of surgical intervention, a cautious exploration of the pancreas after thorough mobilization is most important. Recent use of intraoperative ultrasonography increases the likelihood of finding these occult tumors which locate deeply in the head of the pancreas. Apart from the diagnostic problems, we wish to emphasize the high incidence of malignancy (7/22, 31.8 per cent) in our series. Althout patients with malignant isulinoma had a much better prognosis compared to those with a pancreatic ductal malignancy, pancreatic resection with regional lymphnode dissection seems to be a rational procedure. Enucleation can be done when intraoperative findings of the tumor and regional lymphonode indicate no malignant features and no multiple lesions. However, at the first operation, enucleation is still a procedure of choice, even for the malignant insulinoma in the head with a well-defined capsule and no metastatic lesions, the objective being to avoid a duodenopancreatectomy or total pancreatectomy. These data were reported at the 30th Congress of Société Internationale de Chirurgie, Hamburg, Germany, 1983  相似文献   
10.
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