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   15825篇
  免费   1338篇
  国内免费   496篇
耳鼻咽喉   171篇
儿科学   282篇
妇产科学   376篇
基础医学   2085篇
口腔科学   324篇
临床医学   1853篇
内科学   2862篇
皮肤病学   316篇
神经病学   1075篇
特种医学   646篇
外国民族医学   3篇
外科学   1945篇
综合类   1149篇
一般理论   2篇
预防医学   1011篇
眼科学   444篇
药学   1396篇
  4篇
中国医学   335篇
肿瘤学   1380篇
  2023年   155篇
  2022年   346篇
  2021年   594篇
  2020年   319篇
  2019年   429篇
  2018年   424篇
  2017年   378篇
  2016年   388篇
  2015年   538篇
  2014年   632篇
  2013年   694篇
  2012年   1130篇
  2011年   1200篇
  2010年   716篇
  2009年   603篇
  2008年   873篇
  2007年   853篇
  2006年   819篇
  2005年   771篇
  2004年   694篇
  2003年   598篇
  2002年   520篇
  2001年   467篇
  2000年   403篇
  1999年   395篇
  1998年   153篇
  1997年   158篇
  1996年   179篇
  1995年   152篇
  1994年   112篇
  1993年   87篇
  1992年   196篇
  1991年   182篇
  1990年   156篇
  1989年   137篇
  1988年   129篇
  1987年   108篇
  1986年   107篇
  1985年   103篇
  1984年   78篇
  1983年   72篇
  1982年   56篇
  1981年   55篇
  1980年   47篇
  1979年   60篇
  1978年   50篇
  1977年   33篇
  1975年   27篇
  1974年   43篇
  1968年   25篇
排序方式: 共有10000条查询结果,搜索用时 203 毫秒
11.

Purpose

To evaluate the feasibility of a same-day yttrium-90 (90Y) radioembolization protocol with resin microspheres (including pretreatment angiography, lung shunt fraction [LSF] determination, and radioembolization) for the treatment of hepatocellular carcinoma (HCC) and liver metastases.

Materials and Methods

All same-day radioembolization procedures performed over 1 y (February 2017 to January 2018) were included in this single-institutional retrospective analysis, in which 34 procedures were performed in 26 patients (median age, 63 y; 13 women), 19 with liver metastases and 7 with HCC. Yttrium-90 treatment activities were calculated by body surface area method. Tumor imaging response was assessed by Response Evaluation Criteria In Solid Tumors (RECIST) 1.1 for liver metastases and modified RECIST for HCC. Clinical side effects and adverse events were graded per Common Terminology Criteria for Adverse Events version 4.0.

Results

All planned cases were technically successful, and no cases were canceled for elevated LSF or vascular anatomic reasons. Pretreatment angiography modified the planned 90Y treatment activity in 1 case in which vascular anatomy required a lobar-dose split into 2 for segmental infusions. In 18% of cases, patients were briefly admitted after the procedure for observation or symptom management. Imaging evaluation of initial efficacy at 1 month demonstrated partial response in 25% and stable disease in 67% of patients with liver metastases and partial/complete response in 43% and stable disease in 14% of patients with HCC. Grade ≥ 3 adverse events occurred in 6% of cases, with no systemic therapy–limiting toxicities. The mean total procedure time was 4.2 hours.

Conclusions

A same-day 90Y radioembolization protocol with resin microspheres is feasible in select patients, which can expedite cancer therapy.  相似文献   
12.
13.
14.
Mycophenolate mofetil (MMF) used in a triple-drug regimen has been shown to decrease acute rejection rates, compared to a double-drug regimen. The impact of MMF on late acute rejection (LAR) episodes has not been well described. To investigate the risk of LAR (rejection > or = 6 months post-transplantation) data from the Scientific Registry of Transplant Recipients (SRTR) were used. We studied adult primary liver transplant recipients transplanted between June 1, 1995, and April 30, 2004, with hepatitis C virus (HCV) (n = 3356), hepatitis B virus (HBV) (n = 550) or a nonviral (n = 5740) primary cause of liver disease who were recorded as receiving continuous 3-(MMF + Tacro + steroids) versus 2-drug (Tacro + steroids) therapy for at least 6 months immediately post transplantation. Kaplan-Meier analysis showed significantly lower LAR rates 4 years post-transplant in 3- versus 2-drug HCV, HBV and nonviral disease patients. Multivariate regression confirmed 3- versus 2-drug therapy to be associated with a decreased risk of LAR. Late graft survival was significantly lower at 4 years post-transplant for patients with LAR 6-12 months post-transplantation versus patients with early rejection (78.0% vs. 87.0%, p < 0.001) and no rejection (88.1%, p < 0.001). Three-drug versus 2-drug therapy for a minimum of 6 months may offer a better treatment strategy to avoid the consequences and expense of LAR episodes.  相似文献   
15.
Bombesin improves survival from methotrexate-induced enterocolitis.   总被引:5,自引:0,他引:5       下载免费PDF全文
OBJECTIVE: The authors determined whether bombesin could improve survival from methotrexate (MTX)-induced enterocolitis. SUMMARY BACKGROUND DATA: Bombesin prevents gut mucosal atrophy, which is produced by feeding rats an elemental diet. Administration of MTX produces a lethal enterocolitis in rats fed an elemental diet. METHODS: On treatment day 0, 60 rats were divided randomly into three groups and fed an elemental diet (Vivonex TEN, Sandoz, Minneapolis, MN) as the only source of nutrition. Groups were subdivided further to receive either saline or bombesin (10 micrograms/kg, subcutaneously, three times a day) beginning either on day 0 or day 14. Methotrexate (20 mg/kg, intraperitoneally) was given to all rats 14 days after the start of an elemental diet. RESULTS: Bombesin prevented the mucosal atrophy in the ileum produced by the elemental diet and significantly decreased mortality in rats given MTX (whether given as a pretreatment or at the time of MTX administration). CONCLUSION: Bombesin significantly improved survival in a lethal model of MTX-induced enterocolitis, possibly by maintaining gut mucosal structure. Administration of bombesin to patients receiving chemotherapy may be clinically useful in preventing the severe enterocolitis induced by various chemotherapeutic agents.  相似文献   
16.
17.
研究大学生心理素质与思想品德发展的关系,目的在于分析、发现个体在接受教育过程中的心理运动规律,从而提高思想教育的实效性。本文从马克思主义认识论和实践论的观点出发,依据教育心理学的原理,探讨了心理健康教育与思想品德教育的内在联系和相互作用,提出良好的心理素质是大学生思想品德发展的基础的观点。认为品德的形成与人的心理活动息息相关,个体如果没有良好的品德,将影响其心理素质的完善;同样,没有健全的心理素质,思想品德也不能得到很好的发展。只有思想品德教育与心理健康教育协调发展,共同作用,才能收到良好的教育效果。  相似文献   
18.
T-2 toxin is one of the mycotoxins, a group of type A trichothecenes produced by several fungal genera including Fusarium species. In the present study, we have investigated the apoptotic effects of T-2 toxin on chondrocytes and the relationship between T-2 toxin induced chondrocyte apoptosis and its influence on Bcl-2/Bax protein and mRNA expression. We have also examined the inhibitory effects of selenium on chondrocyte apoptosis induced by T-2 toxin. We have combined morphological and biological techniques to establish the relevance of apoptosis in human chondrocyte death induced by T-2 toxin. Treatment with T-2 toxin caused accelerated apoptosis in a concentration dependent manner. The apoptosis induced by T-2 toxin involved an increased Bax/Bcl-2 ratio. Bcl-2 mRNA expression remained unchanged in chondrocyte apoptosis induced by T-2 toxin treatment, while Bax mRNA expression increased following treatment with T-2 toxin. Selenium could partly block the apoptosis of chondrocytes induced by T-2 toxin through decreasing the Bax/Bcl-2 ratio. These results suggest that, under our experimental conditions, apoptosis of chondrocytes can be induced by T-2 toxin (1-20ng/mL) via the Bcl-2 and Bax proteins, and the Bax/Bcl-2 ratio may play a critical role in governing the susceptibility to apoptosis induced by T-2 toxin in human chondrocytes.  相似文献   
19.
20.
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