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   6564篇
  免费   652篇
  国内免费   1篇
耳鼻咽喉   155篇
儿科学   447篇
妇产科学   209篇
基础医学   584篇
口腔科学   534篇
临床医学   675篇
内科学   1298篇
皮肤病学   163篇
神经病学   461篇
特种医学   251篇
外科学   1386篇
综合类   24篇
一般理论   1篇
预防医学   271篇
眼科学   169篇
药学   360篇
中国医学   8篇
肿瘤学   221篇
  2024年   12篇
  2023年   137篇
  2022年   62篇
  2021年   192篇
  2020年   163篇
  2019年   193篇
  2018年   403篇
  2017年   317篇
  2016年   400篇
  2015年   391篇
  2014年   414篇
  2013年   803篇
  2012年   326篇
  2011年   331篇
  2010年   411篇
  2009年   221篇
  2008年   111篇
  2007年   40篇
  2006年   189篇
  2005年   121篇
  2004年   54篇
  2003年   46篇
  2002年   66篇
  2001年   128篇
  2000年   107篇
  1999年   128篇
  1998年   143篇
  1997年   107篇
  1996年   151篇
  1995年   91篇
  1994年   101篇
  1993年   93篇
  1992年   65篇
  1991年   68篇
  1990年   54篇
  1989年   35篇
  1988年   55篇
  1987年   22篇
  1986年   26篇
  1985年   30篇
  1984年   33篇
  1983年   27篇
  1982年   32篇
  1981年   28篇
  1980年   28篇
  1979年   18篇
  1977年   12篇
  1976年   14篇
  1975年   12篇
  1959年   17篇
排序方式: 共有7217条查询结果,搜索用时 0 毫秒
101.
102.
Clinical Rheumatology - The aim of this study was to evaluate the relationships among the disease activity, illness perception, daily life performance, anxiety and depression status as potential...  相似文献   
103.

From March 13 until May 31, 2020, a complete lockdown in Turkey was planned and implemented by the government of Turkey. The vulnerable population with substance use disorders was affected more than others due to the social isolation measures meant to control the pandemic. This study presents detailed and broad data on drug abuse in suspected cases during the first wave of the COVID-19 pandemic in Turkey and compares the frequencies and patterns of drug abuse before and during the pandemic. The samples were screened by liquid chromatography-high resolution mass spectrometry and liquid chromatography-tandem mass spectrometry. Blood and urine samples of suspected users (n = 9669) were analyzed for drugs of abuse during the first wave of the COVID-19 pandemic and compared with their results (n = 8727) obtained just before the COVID-19 pandemic. The use of party drugs, such as MDMA and cocaine, and the classic illicit drug cannabis was significantly decreased and followed the same trend after complete lockdown was over. In contrast, methamphetamine use increased significantly during the lockdown period and continued after the lockdown. Interestingly, the number of tests that were positive for pregabalin as a misused licit drug increased, and this increase continued after the lockdown. The results showed a significant increase in drug abuse cases and changes in drug abuse trends, with an alteration toward more easily obtainable and lower-priced drugs. Using more dangerous and easily available licit and illicit drugs may cause serious health problems.

  相似文献   
104.
The clinical and functional outcome after restorative proctocolectomy   总被引:17,自引:1,他引:17  
One hundred consecutive patients treated by restorative proctocolectomy with construction of an ileo-anal anastomosis and a J-shaped (n=90) or an S-shaped ileal reservoir were studied prospectively to evaluate postoperative complications and functional outcome and to search for factors that might influence results. There were no deaths. Postoperative complications requiring surgery were pelvic sepsis (3 patients), pouch-related fistula (2), peritonitis following ileostomy closure (3) and small bowel obstruction (6), with an overall relaparotomy rate of 14%. The cumulative risk of pouchitis was 30% at 2 years. The average stool frequency decreased gradually, stabilising at about five evacuations/24 h after 1 year. At that time 9% of patients still had 7 day-time evacuations and 40% had night evacuations (>1/week). These parameters did not improve further with time. Mucous soiling, a frequent problem initially, also diminished with time, occurring in 30% of patients at 1 year. At 2 years, however, this mucous leak occurred in only 20%, suggesting that improvement of continence can be expected to occur even beyond one year. Despite defects in function patient satisfaction was generally excellent. So far only three patients have preferred conversion to an ileostomy. To establish which factors might influence the functional results a specially designed scoring system, combining all functional variables, was used. It was shown that results deteriorated with increasing age and that elderly women tended to have a poorer result than elderly men. Sex, previous parity or postoperative complications appeared not to affect the functional outcome. Male sexual disturbances occurred in 8%. Three had erectile problems and one loss of ejaculation. Female sexual dysfunction was frequent; dyspareunia and/or leaks during intercourse occurred in about 30%. These results confirm that resorative proctocolectomy with construction of an ileal pouch-anal anastomosis can be performed safely with a reasonable complication rate. Although patient satisfaction is often high, the functional results are not perfect, however, and further trials are in progress in this unit to determine whether results can be improved by altering the techniques for fashioning the pouch.  相似文献   
105.
Endothelium is the first physiological barrier between blood and tissues and can be injured by physical or chemical stress, particularly by the drugs used in the cancer therapy. Paclitaxel and doxorubicin are frequently used anticancer drugs and their cardiac side effects are well observed in clinical setting. Their side effects on the endothelium are still not clear enough. There are few investigations assessing the damages elicited by the combination use of chemotherapy agents in animal experimental models. The purpose of this study was to examine and compare the side effects of doxorubicin and paclitaxel on endothelium in vivo. The drugs were administered weekly to rats via intraperitoneal injections singly or in combinations. Lastly, aorta endothelium was examined. The most familiar parts of the aorta endothelium are the nucleus, free ribosomes, Weibel-Palada granules, plasmalemmal vesicles, and clear basement membrane. Examination of the endothelium and the related structures revealed some clear degenerative findings. Notably, administration of a paclitaxel and doxorubicin combinations caused the most dramatic change in ultrastructure, which may disrupt many functions of the endothelium.  相似文献   
106.
Abstract

Objectives: This study explored the association between tissue transglutaminase autoantibody (tTGA), high-risk human leucocyte antigen (HLA) genotypes and islet autoantibodies in children with newly diagnosed type 1 diabetes (T1D).

Patients and methods: Dried blood spots and serum samples were taken at diagnosis from children <18?years of age participating in Better Diabetes Diagnosis (BDD), a Swedish nationwide prospective cohort study of children newly diagnosed with T1D. We analyzed tTGA, high-risk HLA DQ2 and DQ8 (DQX is neither DQ2 nor DQ8) and islet auto-antibodies (GADA, IA-2A, IAA, and three variants of Zinc transporter; ZnT8W, ZnT8R, and ZnT8QA).

Results: Out of 2705 children diagnosed with T1D, 85 (3.1%) had positive tTGA and 63 (2.3%) had borderline values. The prevalence of tTGA was higher in children with the HLA genotypes DQ2/2, DQ2/X or DQ2/8 compared to those with DQ8/8 or DQ8/X (p?=?.00001) and those with DQX/X (p?≤?.00001). No significant differences were found in relation to islet autoantibodies or age at diagnosis, but the presence of tTGA was more common in girls than in boys (p?=?.018).

Conclusion: tTGA at T1D diagnosis (both positive and borderline values 5.4%) was higher in girls and in children homozygous for DQ2/2, followed by children heterozygous for DQ2. Only children with DQ2 and/or DQ8 had tTGA. HLA typing at the diagnosis of T1D can help to identify those without risk for CD.  相似文献   
107.
108.
109.
110.
Odontology - To evaluate the strengthening effect of five different fibers with different placement designs in root canal treated and intracoronally bleached premolars. Seventy extracted...  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