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   515篇
  免费   21篇
  国内免费   20篇
耳鼻咽喉   13篇
儿科学   32篇
妇产科学   6篇
基础医学   51篇
口腔科学   8篇
临床医学   52篇
内科学   119篇
皮肤病学   13篇
神经病学   45篇
特种医学   68篇
外科学   50篇
综合类   19篇
预防医学   26篇
眼科学   4篇
药学   26篇
中国医学   1篇
肿瘤学   23篇
  2023年   3篇
  2022年   8篇
  2021年   10篇
  2020年   11篇
  2019年   9篇
  2018年   18篇
  2017年   11篇
  2016年   16篇
  2015年   22篇
  2014年   20篇
  2013年   28篇
  2012年   26篇
  2011年   20篇
  2010年   15篇
  2009年   22篇
  2008年   17篇
  2007年   27篇
  2006年   14篇
  2005年   11篇
  2004年   6篇
  2003年   8篇
  2002年   12篇
  2001年   12篇
  2000年   5篇
  1999年   7篇
  1998年   14篇
  1997年   13篇
  1996年   19篇
  1995年   8篇
  1994年   18篇
  1993年   12篇
  1992年   3篇
  1991年   2篇
  1990年   4篇
  1989年   13篇
  1988年   5篇
  1987年   10篇
  1986年   14篇
  1985年   12篇
  1984年   7篇
  1983年   7篇
  1982年   7篇
  1981年   9篇
  1980年   7篇
  1979年   2篇
  1978年   1篇
  1977年   6篇
  1975年   4篇
  1973年   1篇
排序方式: 共有556条查询结果,搜索用时 15 毫秒
91.
We report a case of life-threatening hematemesis due to portal hypertension caused by an isolated arterioportal fistula (APF). Intrahepatic APFs are extremely rare and are a cause of presinusoidal portal hypertension. Etiologies for APFs are comprised of precipitating trauma, malignancy, and hereditary hemorrhagic telangiectasia, but these were not the case in our patient. Idiopathic APFs are usually due to congenital vascular abnormalities and thus usually present in the pediatric setting. This is one of the first cases of adult-onset isolated APF who presented with portal hypertension and was successfully managed through endoscopic hemostasis and subsequent interventional radiological embolization.  相似文献   
92.
Essure sterilization produces a local benign tissue response resulting in bilateral occlusion of the fallopian tubes 3 months after insertion. There is a precautionary warning about performing this procedure on immunosuppressed patients. We present a case of successful bilateral tubal occlusion with Essure in a patient with a history of kidney transplantation and receiving immunosuppressive medications.  相似文献   
93.
94.
Cooking methods have been implicated in the etiology of gastrointestinal cancers, reflecting exposure to potential carcinogens as results of cooking. We used a validated food frequency questionnaire and a pretested cooking method questionnaire in 3 groups: 40 esophageal squamous cell carcinoma (ESCC) cases from a high-risk area in northeast of Iran, 40 healthy subjects from the same high-risk area, and 40 healthy subjects from a low-risk area in Southern Iran. We compared the frequency of boiling, grilling, and frying, and the frying score among these 3 groups. We also calculated “frying index” by multiplying the frequency of each fried food item by its frying score. Mean frying to boiling ratios were 18.2:1, 12.8:1, and 2.6:1 for cases, high-risk controls, and low-risk controls, respectively (P < 0.01). Reuse of cooking oil for frying was reported in 37.5% of the ESCC cases, 25% of high-risk controls, and 7.5% of low-risk controls (P < 0.001). Frying index was higher in the high-risk than in the low-risk controls (P < 0.001) and in cases than in the high-risk controls (P < 0.05) after adjusting for smoking, opium use, rural residence, education, and ethnicity. High-temperature cooking and frying may be associated with increased risk of ESCC in high-risk areas.  相似文献   
95.
The authors aimed to describe cell phone and Internet use and assess the correlation of Internet use for health care engagement purposes and HIV clinical outcomes among HIV-positive individuals. The authors conducted a national survey using online social media to examine cell phone and Internet use, self-reported HIV viral load (detectable vs. undetectable), and antiretroviral adherence rating (excellent vs. less than excellent). Participants (N = 1,494) were asked about their Internet use for health care engagement purposes (including e-mailing health care providers, refilling medications online, and making medical appointments online). Approximately 95% of participants accessed the Internet nearly daily or daily in the past month (mean hours on Internet use per day = 5.2) and 55.5% used the Internet for health care engagement purposes. Those who used the Internet for any health care engagement purposes had a 1.52-fold odds of reporting an undetectable viral load (p = .009) and a 1.49-fold odds of reporting excellent adherence (p = .001). Although Internet access and use were similar across racial/ethnic, educational, and socioeconomic groups, disparities existed with the use of the Internet for health care engagement purposes among racial/ethnic minorities, those with low to moderate financial stability, lower education, and history of incarceration. The authors’ data reveal that among HIV-positive users of online social media, use of the Internet for health care engagement purposes is associated with better self-reported virologic and adherence outcomes.  相似文献   
96.

Purpose

Overweight and obesity have been suggested as a risk factor for leukemia. Impaired immune function associated with obesity, increased insulin-like growth factor-I activity and stimulating effects of leptin suggest a possible biological link between anthropometric measures and leukemia. However, evidence from epidemiological studies has been inconsistent. We examined the potential association between prospective measurements of body size and risk of leukemia among participants of the European Prospective Investigation into Cancer and Nutrition (EPIC).

Methods

During follow-up (mean = 11.52 years, standard deviation = 2.63), 671 leukemia (lymphoid leukemia = 50.1 %, myeloid leukemia = 43.2 %) cases were identified. Anthropometric measures including weight, height, body mass index (BMI), waist circumference (WC), hip circumference, and waist-to-hip ratio (WHR) were measured. Cox proportional hazard models were used to explore the association between anthropometric measures and risk of leukemia.

Results

No associations were observed between anthropometric measures and total leukemia, and lymphoid leukemia. Risk of myeloid leukemia significantly increased for higher categories of BMI and WC among women. Analyses by subtype of myeloid leukemia showed an increased risk of acute myeloid leukemia (AML) for higher categories of WHR among women. This association seemed to be reversed for chronic myeloid leukemia. No association between anthropometric measures and myeloid leukemia were observed among men except an increased risk of AML with height.

Conclusion

The study showed no associations between anthropometric measures and total leukemia, and lymphoid leukemia among men and women. A possible association between BMI as general obesity and WC as abdominal obesity and increased risk of myeloid leukemia among women were observed.  相似文献   
97.
LM Lin  YK Chen  DR Lai  YL Huang  HR Chen 《Oral diseases》1997,3(4):232-235
OBJECTIVE: To investigate the cancer-promoting effect of Taiwan betel quid in hamster buccal pouch carcinogenesis.
MATERIALS AND METHODS: Two hundred and fifty-two non-inbred mate adult Syrian golden hamsters were randomly divided into six groups, each containing forty-two animalS. A treatment regimen over a 14-week experimental period was employed with six animals per group being killed at seven different periods (every 2 weeks). The right buccal pouch of each animal was painted three times a week with various combinations of 7, 12-dimethylbenz[a]anthracene (DMBA), Taiwan betel quid extract, dimethyl sulfoxide (DMSO) and mineral oil.
RESULT: Both the number and size of tumors in animals concurrently treated with DMBA and betel quid were significantly higher than those in animals treated with DMBA alone in each killing period of 8, 10, 12 and 14 weekS. No visible tumors but hyperkeratosis and acanthosis were observed in pouches treated with betel quid alone for all killing periods.
CONCLUSION: Our results indicate Taiwan betel quid may be a co-carcinogen in human oral carcinogenesis, if extrapolation can be made from the current animal study.  相似文献   
98.
A total of 192 embalmed cadavers were examined in order to present a detailed study of arterial variations in the upper limb and a meta-analysis of them. The variable terminology previously used was unified into a homogenous and complete classification, with 12 categories covering all the previously reported variant patterns of the arm and forearm.  相似文献   
99.
As a consequence of inhibition of the hepatic cytochrome P450 3A4 isozyme, treatment with HIV protease inhibitors can result in significant drug?drug interactions. One noteworthy interaction is between protease inhibitors and inhaled or intranasal corticosteroids. This interaction can result in adrenal insufficiency and iatrogenic Cushing's syndrome (with symptoms such as rapid weight gain, obesity, facial hirsutism and swelling), as well as hypertension, osteoporosis and decreased CD4 cell count. In this paper, we review and unite pharmacokinetic data, case reports and current research regarding this drug?drug interaction in order to suggest options for the clinical management of HIV‐positive patients requiring treatment with protease inhibitors and inhaled or intranasal corticosteroids.  相似文献   
100.
Percutaneous drainage access: a simplified coaxial technique   总被引:1,自引:0,他引:1  
We describe an access technique that we have used in 150 nephrostomy and biliary drainage procedures and for access to some abscesses and viscera. The system provides safe coaxial access with a 22-gauge removable hub needle, which then acts as a guide wire and is replaced by an 18-gauge cannula. A major advantage is that only one guide wire is used (0.038-inch) for the entire drainage procedure. No significant complications have occurred to date with this method.  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