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   182003篇
  免费   32780篇
  国内免费   2727篇
耳鼻咽喉   5623篇
儿科学   5679篇
妇产科学   2828篇
基础医学   8465篇
口腔科学   2332篇
临床医学   29064篇
内科学   53011篇
皮肤病学   8656篇
神经病学   17013篇
特种医学   8506篇
外国民族医学   1篇
外科学   44552篇
综合类   453篇
现状与发展   72篇
一般理论   5篇
预防医学   8481篇
眼科学   3894篇
药学   4219篇
  2篇
中国医学   493篇
肿瘤学   14161篇
  2024年   700篇
  2023年   4976篇
  2022年   1945篇
  2021年   4275篇
  2020年   6518篇
  2019年   2898篇
  2018年   8252篇
  2017年   8034篇
  2016年   9443篇
  2015年   9819篇
  2014年   17103篇
  2013年   17482篇
  2012年   8390篇
  2011年   8334篇
  2010年   11922篇
  2009年   15586篇
  2008年   7737篇
  2007年   5773篇
  2006年   8039篇
  2005年   5203篇
  2004年   4129篇
  2003年   2967篇
  2002年   2891篇
  2001年   4553篇
  2000年   3708篇
  1999年   3698篇
  1998年   3825篇
  1997年   3579篇
  1996年   3460篇
  1995年   3279篇
  1994年   2026篇
  1993年   1631篇
  1992年   1513篇
  1991年   1553篇
  1990年   1222篇
  1989年   1301篇
  1988年   1128篇
  1987年   955篇
  1986年   973篇
  1985年   774篇
  1984年   588篇
  1983年   555篇
  1982年   539篇
  1981年   434篇
  1980年   371篇
  1979年   329篇
  1978年   350篇
  1977年   419篇
  1975年   295篇
  1972年   317篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.

Background

Rosacea is a chronic inflammatory skin condition whose etiology has been linked to mast cells and the antimicrobial peptide cathelicidin LL-37. Individuals with refractory disease have demonstrated clinical benefit with periodic injections of onabotulinum toxin, but the mechanism of action is unknown.

Objectives

To investigate the molecular mechanism by which botulinum toxin improves rosacea lesions.

Methods

Primary human and murine mast cells were pretreated with onabotulinum toxin A or B or control. Mast cell degranulation was evaluated by β-hexosaminidase activity. Expression of botulinum toxin receptor Sv2 was measured by qPCR. The presence of SNAP-25 and VAMP2 was established by immunofluorescence. In vivo rosacea model was established by intradermally injecting LL-37 with or without onabotulinum toxin A pretreatment. Mast cell degranulation was assessed in vivo by histologic counts. Rosacea biomarkers were analyzed by qPCR of mouse skin sections.

Results

Onabotulinum toxin A and B inhibited compound 48/80-induced degranulation of both human and murine mast cells. Expression of Sv2 was established in mouse mast cells. Onabotulinum toxin A and B increased cleaved SNAP-25 and decreased VAMP2 staining in mast cells respectively. In mice, injection of onabotulinum toxin A significantly reduced LL-37-induced skin erythema, mast cell degranulation, and mRNA expression of rosacea biomarkers.

Conclusions

These findings suggest that onabotulinum toxin reduces rosacea-associated skin inflammation by directly inhibiting mast cell degranulation. Periodic applications of onabotulinum toxin may be an effective therapy for refractory rosacea and deserves further study.  相似文献   
4.

Background

In a pooled analysis of the phase 3 Controlled Myelofibrosis Study With Oral JAK Inhibitor Treatment I (COMFORT-I) and COMFORT-II clinical trials, adult patients with intermediate-2 or high-risk myelofibrosis who received oral ruxolitinib at randomization or after crossover from placebo or best available therapy (BAT) had improved overall survival (OS).

Methods

This post hoc analysis of pooled COMFORT data examined relevant disease outcomes based on the disease duration (≤12 or >12 months from diagnosis) before ruxolitinib initiation.

Results

The analysis included 525 patients (ruxolitinib: ≤12 months, n = 84; >12 months, n = 216; placebo/BAT: ≤12 months, n = 66; >12 months, n = 159); the median age was 65.0–70.0 years. Fewer thrombocytopenia and anemia events were observed among patients who initiated ruxolitinib treatment earlier. At Weeks 24 and 48, the spleen volume response (SVR) was higher for patients who initiated ruxolitinib earlier (47.6% vs. 32.9% at Week 24, p = .0610; 44.0% vs. 26.9% at Week 48, p = .0149). In a multivariable analysis of factors associated with spleen volume reduction, a logistic regression model that controlled for confounding factors found that a significantly greater binary reduction was observed among patients with shorter versus longer disease duration (p = .022). At Week 240, OS was significantly improved among patients who initiated ruxolitinib earlier (63% [95% CI, 51%‒73%] vs. 57% [95% CI, 49%‒64%]; hazard ratio, 1.53; 95% CI, 1.01‒2.31; p = .0430). Regardless of disease duration, a longer OS was observed for patients who received ruxolitinib versus those who received placebo/BAT.

Conclusions

These findings suggest that earlier ruxolitinib initiation for adult patients with intermediate-2 and high-risk myelofibrosis may improve clinical outcomes, including fewer cytopenia events, durable SVR, and prolonged OS.

Plain Language Summary

  • Patients with myelofibrosis, a bone marrow cancer, often do not live as long as the general population. These patients may also have an enlarged spleen and difficult symptoms such as fatigue.
  • Two large clinical trials showed that patients treated with the drug ruxolitinib lived longer and had improved symptoms compared to those treated with placebo or other standard treatments.
  • Here it was examined whether starting treatment with ruxolitinib earlier (i.e., within a year of diagnosis) provided benefits versus delaying treatment.
  • Patients who received ruxolitinib within a year of diagnosis lived longer and experienced fewer disease symptoms than those whose treatment was delayed.
  相似文献   
5.
ABSTRACT

Abortion is legal in South Africa, but negative abortion attitudes remain common and are poorly understood. We used nationally representative South African Social Attitudes Survey data to analyze abortion attitudes in the case of fetal anomaly and in the case of poverty from 2007 to 2016 (n = 20,711; ages = 16+). We measured correlations between abortion attitudes and these important predictors: religiosity, attitudes about premarital sex, attitudes about preferential hiring and promotion of women, and attitudes toward family gender roles. Abortion acceptability for poverty increased over time (b = 0.05, p < .001), but not for fetal anomaly (b = ?0.008, p = .284). Highly religious South Africans reported lower abortion acceptability in both cases (Odds Ratio (OR)anomaly = 0.85, p = .015; ORpoverty = 0.84, p = .02). Premarital sex acceptability strongly and positively predicted abortion acceptability (ORanomaly = 2.63, p < .001; ORpoverty = 2.46, p < .001). Attitudes about preferential hiring and promotion of women were not associated with abortion attitudes, but favorable attitudes about working mothers were positively associated with abortion acceptability for fetal anomaly ((ORanomaly = 1.09, p = .01; ORpoverty = 1.02, p = .641)). Results suggest negative abortion attitudes remain common in South Africa and are closely tied to religiosity, traditional ideologies about sexuality, and gender role expectations about motherhood.  相似文献   
6.
7.
8.
9.
10.
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