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   829篇
  免费   57篇
  国内免费   2篇
耳鼻咽喉   5篇
儿科学   17篇
妇产科学   7篇
基础医学   87篇
口腔科学   6篇
临床医学   148篇
内科学   161篇
皮肤病学   23篇
神经病学   89篇
特种医学   15篇
外科学   113篇
综合类   5篇
一般理论   1篇
预防医学   82篇
眼科学   15篇
药学   52篇
中国医学   1篇
肿瘤学   61篇
  2023年   16篇
  2022年   16篇
  2021年   25篇
  2020年   22篇
  2019年   30篇
  2018年   30篇
  2017年   16篇
  2016年   20篇
  2015年   14篇
  2014年   17篇
  2013年   36篇
  2012年   67篇
  2011年   66篇
  2010年   38篇
  2009年   41篇
  2008年   46篇
  2007年   40篇
  2006年   48篇
  2005年   40篇
  2004年   47篇
  2003年   29篇
  2002年   28篇
  2001年   11篇
  2000年   3篇
  1999年   11篇
  1998年   6篇
  1997年   4篇
  1996年   3篇
  1995年   9篇
  1994年   11篇
  1993年   3篇
  1992年   15篇
  1991年   2篇
  1990年   8篇
  1989年   12篇
  1988年   9篇
  1987年   9篇
  1986年   13篇
  1985年   6篇
  1983年   3篇
  1982年   1篇
  1981年   1篇
  1980年   1篇
  1979年   1篇
  1978年   2篇
  1977年   4篇
  1972年   2篇
  1944年   1篇
  1941年   2篇
  1938年   1篇
排序方式: 共有888条查询结果,搜索用时 46 毫秒
1.
OBJECTIVE: To quantify the dietary calcium and vitamin D intake in adult renal-transplant recipients attending at a large teaching hospital in Ireland for follow-up. SETTING: Outpatient renal-transplant follow-up clinic. SUBJECTS: Fifty-nine adult renal transplant recipients (58% male) with a mean age of 46 years, a median transplant duration of 6 years, and a mean estimated glomerular filtration rate (eGFR) of 50 mL/min per 1.73 m2. Fifty-three percent were at National Kidney Foundation stage 3 chronic kidney disease, and 14% had stage 4 chronic kidney disease. INTERVENTION: This cross-sectional, observational study used a tailored food frequency questionnaire specific for calcium and vitamin D intake in Irish adults, which was completed during a face-to-face interview with each subject. MAIN OUTCOME MEASURE: The main outcome measure was the average daily dietary and supplemented calcium and vitamin D intake. RESULTS: The median interquartile range (IQR) dietary calcium intake was 820 mg/day (range, 576-1,177 mg/day), and was similar in men and women (recommended intake > or = 1,000 mg/day in adult men and nonmenopausal adult women, > or = 1,500 mg/day in menopausal women). Five participants received calcium supplementation. Overall, 59% of men and 64% of women had total calcium intakes below the recommended amounts. The median IQR estimated dietary vitamin D intake was 5.2 microg/day (range, 2.4-6.4 microg/day) in women, and 4.6 microg/day (range, 2.2-6.6 microg/day) in men (recommended intake, > or = 10 microg/day). Six subjects received vitamin D supplementation. Total vitamin D intakes were suboptimal in 91% of men and 87% of women. Dietary calcium and vitamin D intakes significantly correlated with each other, but neither was significantly related to eGFR category, and was similarly low in both presumed menopausal women and in the initial year posttransplantation. CONCLUSION: These findings suggest that dietary and total calcium and vitamin D intakes in adult renal-transplant patients are in many cases inadequate.  相似文献   
2.
Objective Detection of HPV DNA in oral and genital lesions of a heterosexual male. 4 months after oral and vaginal intercourse with a woman with vulvar warts. Passible modes of acquisition of oral HPV infection in the male sexual partner are discussed. Setting Genitourinary Medicine clinic. Methods Polymerase chain reaction amplification of genomic DNA from oral and genital lesions. HPV DNA typing by dot blot hybridization. Results HPV DNA types 6 and 11 were identified in a polypoid tongue lesion and in a penile wart from the male sexual partner. Conclusions The acquisition of oral HPV infection in the male sexual partner may have resulted from genital-oral HPV transfer, either by direct contact with vulvar warts or by digital self-inoculation.  相似文献   
3.
Identifying alcoholism in medical patients   总被引:1,自引:0,他引:1  
  相似文献   
4.
Breast-feeding has numerous advantages, yet the trend to breast-feed is declining. Nurses, as well as patients, can benefit from increasing their knowledge base about breast-feeding. Nurses have an important role to play in supporting breast-feeding mothers with current research-based knowledge. More importantly, nurses also serve as patient advocates for the neonate. The use of appropriate nursing diagnoses may facilitate an optimal breast-feeding experience for our smallest consumer, the neonate.  相似文献   
5.
Several research groups have reported that the oral administration of propranolol with protein-rich food leads to a marked increase (mean + 60%) in the area under the drug plasma concentration-time curve (AUC oral) of this highly metabolized and well-absorbed drug. It has been postulated that this "food effect" is caused at least in part by a transient increase in hepatic blood flow (QH) with its associated decrease in first-pass metabolism (hepatic extraction is a monotonic decreasing function of QH). A randomized crossover study using postural manipulations to produce changes in QH of the magnitude observed after food consumption (20% to 50%) was performed in an attempt to isolate the contribution of transient changes in QH to the food effect phenomenon. A solution of 80 mg propranolol HCl was taken orally and subjects were randomly assigned to postural manipulation protocols that should change QH such that AUC oral would be minimized (phase 1) or maximized (phase 2). Estimated QH (indocyanine green total body clearance from blood) was determined before and at three time points during each phase. It was observed that indocyanine green total body clearance during periods of standing was 15% to 40% below that observed during periods of seating (significant at p less than 0.05 for many of the appropriate comparisons). However, AUC oral for propranolol was not affected (mean +/- 1 SD; AUC phase 2/AUC phase 1+= 0.98 +/- 0.28) by these changes in QH, which are comparable to those encountered after food consumption.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
6.
This bibliography contains both foreign (in brackets) and English language citations obtained from Index to Dental Literature, Index Medicus, and Psychological Abstracts for the period January 1986 to December 1987. Although a careful search of these indexes was performed, every relevant citation may not be included. Comments or suggestions regarding this bibliography are welcomed by the author.  相似文献   
7.
Current HIV/AIDS statistics show that women account for almost 60% of HIV infections in Sub-Saharan Africa. HIV prevention tools such as male and female condoms, abstinence and monogamy are not always feasible options for women due to various socio-economic and cultural factors. Microbicides are products designed to be inserted in the vagina or rectum prior to sex to prevent HIV acquisition.  相似文献   
8.
This study examined the eyeblink rate during non-visual problem solving. A 2 × 2 × 2 factorial design compared eyeblink rates for easy and difficult problems, internally and externally directed attention, and numerical and alphabetical tasks. The major finding was a higher eyeblink rate for difficult problems. There was also a significant interaction between difficulty and the direction of attention; internally directed attention yielded higher blink rates only during the solution of easy problems. Range-corrected data yielded the same pattern of results, but F-values were consistently higher and accounted for a larger proportion of the variance.  相似文献   
9.
Prevention Science - The adoption and effective delivery of evidence-based interventions within “real-world” community-based, primary health care service settings are of crucial...  相似文献   
10.
DNA immunization: mechanistic studies   总被引:22,自引:0,他引:22  
Whitton JL  Rodriguez F  Zhang J  Hassett DE 《Vaccine》1999,17(13-14):1612-1619
DNA immunization works, as has been amply demonstrated in a variety of microbial and tumor models. However, the mechanisms which underpin its success remain unclear. Using intramuscular delivery of DNA, we wish to precisely define how DNA-encoded antigens induce CD8+ T-cells (most cytotoxic T-cells; CTL), CD4+ T-cells (mostly helper cells) and antibodies; and to use the accrued knowledge to rationally manipulate DNA vaccines, thus enabling us to optimize each of the above three types of immune response. We consider it likely that different mechanisms operate in each case. We have designed a DNA vaccine which induces CTL, but not antibodies. We will present evidence that CTL are induced by endogenously-synthesized protein, not by protein released from cells; and that in the absence of release of intact protein, antibodies are not induced, while CTL induction remains strong. We have used plasmid-encoded minigenes and have found that these short sequences also induce CTL; this, too, argues that CTL are induced by antigens presented following endogenous synthesis. We are attempting to determine how antigens are released from transfected cells, to interact with B-cells and induce antibodies, and are currently evaluating the CD4 responses induced by DNA vaccines.  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