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   519篇
  免费   48篇
  国内免费   6篇
耳鼻咽喉   1篇
儿科学   15篇
妇产科学   9篇
基础医学   33篇
口腔科学   32篇
临床医学   47篇
内科学   111篇
皮肤病学   9篇
神经病学   20篇
特种医学   100篇
外科学   48篇
综合类   67篇
预防医学   37篇
眼科学   6篇
药学   19篇
中国医学   4篇
肿瘤学   15篇
  2023年   2篇
  2022年   5篇
  2021年   10篇
  2020年   7篇
  2019年   7篇
  2018年   16篇
  2017年   14篇
  2016年   12篇
  2015年   16篇
  2014年   19篇
  2013年   29篇
  2012年   21篇
  2011年   24篇
  2010年   43篇
  2009年   28篇
  2008年   17篇
  2007年   21篇
  2006年   24篇
  2005年   12篇
  2004年   9篇
  2003年   11篇
  2002年   4篇
  2001年   6篇
  2000年   13篇
  1999年   5篇
  1998年   15篇
  1997年   17篇
  1996年   17篇
  1995年   15篇
  1994年   15篇
  1993年   16篇
  1992年   2篇
  1991年   3篇
  1990年   6篇
  1989年   11篇
  1988年   8篇
  1987年   7篇
  1986年   6篇
  1985年   11篇
  1984年   5篇
  1983年   4篇
  1982年   2篇
  1981年   8篇
  1980年   4篇
  1979年   3篇
  1978年   3篇
  1977年   5篇
  1976年   5篇
  1975年   7篇
  1968年   1篇
排序方式: 共有573条查询结果,搜索用时 31 毫秒
71.

Background

Body image (BI) is a multidimensional construct that includes perceptual, attitudinal, behavioural components, and feedback from other people''s perception of oneself. The feedback from others and the degree to which one accepts or rejects it can determine self evaluation and perception. Body weight perception is a strong determinant of nutritional habits and weight management among adolescents. One of the barriers to reducing rise in obesity prevalence could be its cultural acceptability in some developing countries.

Objective

To explore the gender influences on perception of self- and opposite-sex body images (BI), perceived body weight and the actual body weight categories at which discrepancies occur among the perceived BIs in undergraduates.

Methods

This was a survey of perceptual dimension of BI, perceived body weight and actual body weight carried out in 121 undergraduates aged 21–29years.

Results

Discrepancies occurred between self-perceived BI and each of actual body weight (p= 0.00 at 0.00–0.02 confidence interval (CI)), perceived body weight (p= 0.01 at 0.000–0.02 CI) and self-ideal BI (p= 0.03 at 0.000–0.05 CI) of normal-weight males. Self-perceived BI and perceived body weight also differed in normal-weight females (p= 0.02 at 0.000–0.04 CI). Discrepancies (p= 0.02 at 0.00–0.04 CI) occurred between self-perceived BI and self-ideal BI, and between self-perceived BI and desired BI (p= 0.02 at 0.00–0.04 CI) in overweight females. Gender differences occurred for self-ideal BI (p= 0.00 at 0.00–0.02 CI), ideal image for the opposite sex (IBIOS) (p= 0.02 at 0.00–0.04 CI) and desired BI (p= 0.00 at 0.00–0.02 CI).

Conclusion

Normal-weight males perceived their BI differently from their actual body weight, perceived body weight and self-ideal BI whereas normal-weight females perceived their BI differently from only their perceived body weight. Discrepancies occur between self-ideal BI and self-perceived BI, and between self-perceived BI and desired BI in overweight females. There are differential perceptions of self-ideal BI, IBIOS and desired BI between males and females.  相似文献   
72.
目的研究低温含血保护液微流量持续灌注对热缺血猪心的保护作用,探讨心脏移植中供心保护的有效方法。方法24只离体猪心随机分为实验组(n=12,热缺血10min,4℃含血保护液持续灌注8h)和对照组(n=12,热缺血10min,4℃保护液浸泡保存8h),进行原位心脏移植,分别监测心脏复跳及血流动力学情况:心率(HR)、平均动脉压(MAP)、心输出量(CO),心肌肌钙蛋白T(cTnT)、肌红蛋白(Mb)水平。结果实验组心脏复跳情况、血流动力学优于对照组;对照组心肌蛋白显著高于实验组(P〈0.05)。结论低温含血保护液微流量持续灌注对热缺血猪心的心功能以及心肌组织有较好的保护作用。  相似文献   
73.

Objective

We have previously reported data from the German cohort of the multinational observational prospective RAINBOW survey which assessed the tolerability and efficacy of ritonavir-boosted saquinavir (SQV/r)-containing regimens over 48 weeks in routine clinical practice. This analysis presents data from antiretroviral (ART)-naïve and pretreated but protease inhibitor (PI)-naïve patients treated in a long-term one line (96 weeks) follow-up of the initial study.

Methods

All ART-and PI-naïve patients from the initial RAINBOW cohort who had recorded data to one line 96 weeks of treatment were eligible for inclusion in the current analysis. Efficacy assessments included the proportion of patients with HIV-1 RNA < 50 and < 400 copies/mL and changes in CD4 cell count from baseline to week 96. Tolerability assessments included changes in liver enzymes and lipid levels from baseline to week 96. For evaluation of efficacy, intent-to-treat analysis, in which missing values were recorded as failure (ITT), and last-observation-carried-forward (LOCF) analysis were used. Metabolic parameters were assessed using LOCF analysis.

Results

The analysis included 175 ART-naïve and 109 pretreated but PI-naïve patients. After 96 weeks, a similar proportion of patients in the ART-naïve and in the pretreated but Pi-naïve group had HIV-1 RNA levels < 400 copies/mL (68.0% and 70.6% [ITT], respectively; 96.6% and 90.8% [LOCF], respectively). The proportion of patients with HIV RNA < 50 copies/mL was higher in the ART-naïve group compared with the pretreated but PI-naïve group (61.1% and 56.9% [ITT], respectively; 84.0% and 75.2% [LOCF], respectively). Median change in CD4 cell count from baseline to week 96 was''+263 cells/mm3 (IQR 170; 384. LOCF; p < 0.0001) in the ART-naïve group, and one line +181 cells/mm3 (IQR 60; 309. LOCF; p < 0.0001) in the pretreated but PI-naïve group. Treatment was well tolerated, with only 2.5% of patients withdrawing from treatment due to side effects. There were no clinically relevant changes in liver enzyme levels. Overall total cholesterol, triglyceride, and low-and high-density lipoprotein levels increased to week 96, although levels remained within normal ranges in the majority of ART-naïve and pretreated patients.

Conclusions

This follow-up analysis confirms the long term efficacy and tolerability of SQV/r in ART-naïve and pretreated but PI-naïve patients in the real-life clinical setting.  相似文献   
74.
75.
76.
Recently, moderate (CAG)>20 repeat expansions in the alpha1A-voltage- dependent calcium channel gene (CACNL1A4) have been identified in a previously unmapped type of SCA which has been named SCA6. We investigated the (CAG)n repeat length of the CACNL1A4 gene in 733 patients with sporadic ataxia and in 46 German families with dominantly inherited SCA which do not harbor the SCA1, SCA2, or MJD1/SCA3 mutation, respectively. The SCA6 (CAG)n expansion was identified in 32 patients most frequently with late manifestation of the disease. The (CAG)n stretch of the affected allele varied between 22 and 28 trinucleotide units and is therefore the shortest trinucleotide repeat expansion causing spinocerebellar ataxia. The (CAG)n repeat length is inversely correlated with the age at onset. In 11 parental transmissions of the expanded allele no repeat instability has been observed. Repeat instability was also not found for the normal allele investigating 431 meioses in the CEPH families. Analyzing 248 apparently healthy octogenerians revealed one allele of 18 repeats which is the longest normal CAG repeat in the CACNL1A4 gene reported. The SCA6 mutation causes the disease in approximately 10% of autosomal dominant SCA in Germany. Most importantly, the trinucleotide expansion was observed in four ataxia patients without obvious family history of the disease which necessitates a search for the SCA6 (CAG)n expansion even in sporadic patients.   相似文献   
77.
目的利用CRISPR/Cas9系统,敲除小鼠黑色素瘤细胞系的MATP基因,为MATP基因的功能研究奠定基础。方法利用http://crispr.mit.edu/网站,设计针对MATP的特异性引物,并将引物链接到pCAS9/gRNA1载体。将阳性载体转染小鼠黑色素瘤细胞系B16F10,利用无限稀释的方法获得转染后的单克隆细胞株。提取不同细胞株的基因组,通过测序的方法进一步筛选出发生MATP基因切割的细胞株,并利用Western-blot的方法验证MATP的表达情况。结果成功获得了3株MATP基因敲除的细胞株,Western-blot结果表明,该细胞株不表达MATP蛋白。结论利用pCAS9/gRNA1载体,可以实现B16F10细胞系MATP基因的敲除。  相似文献   
78.
79.
紫草辅助米非司酮抗早孕对生殖激素的影响   总被引:28,自引:2,他引:26  
为了探讨紫草辅助米非司酮抗早孕时对早孕妇女血中生殖激素的影响 ,88例早孕妇女随机分成服用米非司酮、紫草、米非司酮加紫草组和空白对照组 ,比较用药前后血人绒毛膜促性腺激素β亚单位 (β-h CG)、卵泡刺激素 ( F SH)、黄体生成素 ( L H)、雌二醇 ( E2 )、孕酮 ( P)和睾酮 ( T)的变化。结果 :单用米非司酮或紫草均对 β-h CG有一定的抑制作用 ,二者合用抑制作用更加明显 ;单用紫草对血中 FSH、 L H有较明显的抑制作用 ,对 E2 、P及 T无明显影响。认为紫草对绒毛功能有一定的影响 ,与米非司酮合用影响更明显 ;紫草对垂体生殖激素有明显的抑制作用。但是否与紫草能提高药物流产效果有关 ,尚需进一步研究。  相似文献   
80.
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