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   4728篇
  免费   326篇
  国内免费   36篇
耳鼻咽喉   74篇
儿科学   116篇
妇产科学   94篇
基础医学   710篇
口腔科学   485篇
临床医学   478篇
内科学   921篇
皮肤病学   133篇
神经病学   401篇
特种医学   42篇
外科学   399篇
综合类   31篇
一般理论   1篇
预防医学   516篇
眼科学   86篇
药学   378篇
中国医学   34篇
肿瘤学   191篇
  2024年   8篇
  2023年   72篇
  2022年   145篇
  2021年   274篇
  2020年   169篇
  2019年   204篇
  2018年   257篇
  2017年   157篇
  2016年   196篇
  2015年   212篇
  2014年   294篇
  2013年   281篇
  2012年   436篇
  2011年   491篇
  2010年   250篇
  2009年   195篇
  2008年   280篇
  2007年   309篇
  2006年   218篇
  2005年   180篇
  2004年   147篇
  2003年   98篇
  2002年   102篇
  2001年   11篇
  2000年   11篇
  1999年   6篇
  1998年   12篇
  1997年   7篇
  1996年   11篇
  1995年   5篇
  1994年   8篇
  1993年   6篇
  1992年   6篇
  1991年   1篇
  1990年   9篇
  1989年   1篇
  1988年   1篇
  1986年   4篇
  1985年   1篇
  1984年   3篇
  1982年   1篇
  1981年   1篇
  1980年   2篇
  1979年   2篇
  1978年   1篇
  1977年   1篇
  1974年   1篇
  1973年   2篇
  1968年   1篇
排序方式: 共有5090条查询结果,搜索用时 15 毫秒
101.
This study evaluated the importance of the union between dentin collagen and three different adhesive materials. Sixty Class V restorations were prepared on the buccal and lingual surfaces of 30 recently extracted human premolars, with the cervical margins in dentin and the occlusal margins in enamel. These restorations were distributed to three groups of 20 cavities each based on the employed adhesive system used: Group A: Single Bond; Group B: Prime&Bond NT; Group C: One Coat Bond. Each group was subdivided according to dentin treatment: (1) manufacturers' adhesive protocol and (2) removal of the collagens fibers (total etch + sodium hypochlorite 5% for two minutes) + adhesive protocol. After the restorations were completed, the teeth were stored in saline solution (24 hours/37 degrees C), subjected to thermal cycling, washing and scoring according to dye penetration. Dye penetration was evaluated, with the numbers ranging from 0 (no infiltration) to 3 (greatest infiltration). When the dentin microleakage scores were compared in subgroups A1XA2, B1XB2 and C1XC2, the Mann-Whitney Test revealed significant differences between groups B and C (p < 5%). The better results were shown in subgroups B2 (p = 0.0345) and C2 (p = 0.0029). The results showed that the collagen fibrils were not necessary for adhesion, and their removal positively influenced the marginal sealing of Prime&Bond NT and One Coat Bond.  相似文献   
102.
An interruption was found to have no consistent definition in either healthcare or nonhealthcare literature. Walker and Avant's 8-step method of concept analysis was used to clarify, define, and develop a conceptual model of interruption. The analysis led to the identification of 5 defining attributes that include (1) a human experience; (2) an intrusion of a secondary, unplanned, and unexpected task; (3) discontinuity; (4) externally or internally initiated; and (5) situated within a context. Use of the defining attributes will be extended to form a category of interruption within a taxonomy of activity.  相似文献   
103.

Background

The study evaluated the effects of two sphingosine derivatives N-(2-tert-butoxycarbamylhexadecyl)glutaramide (AA) and N-(1-benzyloxyhexadec-2-yl)glutaramide (OA) in different models of hypersensitivity in mice.

Methods

Male Swiss mice were orally pre-treated with AA or OA (0.3–3 mg/kg). After 1 h, they received λ-carrageenan (300 μg/paw), lipopolysaccharide (LPS; 100 ng/paw), bradykinin (BK; 500 ng/paw) or prostaglandin E2 (PGE2; 0.1 nmol/paw) or epinephrine (100 ng/paw), and the mechanical withdrawal thresholds were evaluated using von Frey filament (0.6 g) at different time points. The effect of the compounds against inflammatory and neuropathic pain was also evaluated using complete Freund’s adjuvant (CFA), or by performing partial sciatic nerve ligation (PSNL).

Results

Animals pre-treated with AA and OA reduced hypersensitivity induced by carrageenan, LPS and BK, and modest inhibition of PGE2-induced hypersensitivity and carrageenan-induced paw oedema were observed in mice treated with OA. Though the partial effect presented by AA and OA, when dosed once a day, both compounds were able to significantly reduce the persistent inflammatory and neuropathic pain induced by CFA and PSNL, respectively.

Conclusion

These results demonstrate that the sphingosine derivatives AA and OA present important anti-hypersensitive effects, suggesting a possible interaction with the kinin signalling pathway. This may represent an interesting tool for the management of acute and chronic pain, with good bioavailability and safety.  相似文献   
104.
Annals of Surgical Oncology - Surgery results in severe impairment of natural killer (NK) cell cytotoxicity (NKC) and activity (NKA, cytokine secretion), and a dramatic drop in arginine levels....  相似文献   
105.
Lasers in Medical Science - Several treatment options are proposed for the management of pelvic floor myofascial pain (PFMP). Manual therapy, such as vaginal stretching (VS), is one of these...  相似文献   
106.
Lasers in Medical Science - This study refers to clinical and histologic analysis of effects on photorejuvenation after one single treatment of fractional CO2 laser with low fluence and low...  相似文献   
107.
108.
109.
110.

Objective

To evaluate patients'' quality of life aspects after pacemaker implantation, relating it to gender, age, and implantation timespan.

Methods

A total of 107 clinically stable patients of both genders (49.5% women and 50.5% men) over 18 years old (average 69.3±12.6 years) and presenting an implantation timespan of three to 12 months (average 6.36±2.99 months) were evaluated. The evaluation included personal, clinical, and implant data as well as quality of life questionnaires (AQUAREL and SF-36). Statistical analysis was conducted using the t test and Pearson correlation, with a 5% significance level.

Results

The lowest SF-36 score referred to physical aspects, and the highest score referred to social aspects. In AQUAREL, the lowest score referred to dyspnea, and the highest referred to discomfort. There was a significant association between gender and quality of life in SF-36 (physical functioning and emotional aspects) and in AQUAREL (dyspnea). A negative correlation was observed between age and quality of life (functional capacity in SF-36, and discomfort in AQUAREL) in relation to implantation timespan, a correlation with vitality from SF-36.

Conclusion

Lower quality of life scores were found in physical aspects and dyspnea; and higher scores in social aspects and discomfort. Men presented higher quality of life scores related to physical functioning, emotional aspects and dyspnea. As age increases, quality of life worsens regarding functional capacity and discomfort; and the longer the pacemaker implantation timespan, the worse quality of life when it comes to vitality. Gender, age, and implantation timespan influence quality of life; thus, these variables must be considered in strategies for improving quality of life of patients with pacemakers.  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