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   7984篇
  免费   768篇
  国内免费   417篇
耳鼻咽喉   74篇
儿科学   153篇
妇产科学   89篇
基础医学   932篇
口腔科学   197篇
临床医学   821篇
内科学   1361篇
皮肤病学   95篇
神经病学   405篇
特种医学   379篇
外国民族医学   1篇
外科学   1014篇
综合类   1037篇
现状与发展   3篇
一般理论   1篇
预防医学   769篇
眼科学   101篇
药学   760篇
  2篇
中国医学   411篇
肿瘤学   564篇
  2024年   20篇
  2023年   107篇
  2022年   246篇
  2021年   295篇
  2020年   227篇
  2019年   200篇
  2018年   222篇
  2017年   232篇
  2016年   246篇
  2015年   252篇
  2014年   398篇
  2013年   408篇
  2012年   581篇
  2011年   600篇
  2010年   376篇
  2009年   339篇
  2008年   439篇
  2007年   451篇
  2006年   421篇
  2005年   396篇
  2004年   347篇
  2003年   374篇
  2002年   325篇
  2001年   229篇
  2000年   168篇
  1999年   130篇
  1998年   72篇
  1997年   63篇
  1996年   52篇
  1995年   33篇
  1994年   49篇
  1993年   34篇
  1992年   64篇
  1991年   54篇
  1990年   56篇
  1989年   65篇
  1988年   52篇
  1987年   71篇
  1986年   56篇
  1985年   57篇
  1984年   41篇
  1983年   32篇
  1982年   22篇
  1981年   23篇
  1980年   16篇
  1979年   37篇
  1978年   25篇
  1977年   18篇
  1975年   16篇
  1974年   21篇
排序方式: 共有9169条查询结果,搜索用时 15 毫秒
1.
2.
目的本研究立足于项目组前期研究的成果上,积极探索吉林辽宁两省目标设置水平的差异,并进一步探究受目标设置影响下的工作落实结果情况,探讨产生差异的原因。 方法以系统穷尽的方式收集吉林辽宁两省2000至2017年有关目标与工作落实情况的指标,利用Spearman相关和线性回归分析吉林辽宁两省目标设置对于突发应急工作落实情况的影响。 结果吉林辽宁两省突发应急领域的目标设置水平与工作落实情况总体均呈现上升趋势,截至2017年,吉林目标设置水平与工作落实情况分别为46%与60%,辽宁为60%与53.3%,且目标设置水平与工作落实呈正相关。 结论有公众需要为依据且定量可考的目标设置对于工作落实、推进、完善具有积极的正反馈作用,建立科学量化的突发应急目标设置评价体系是适宜可行的。  相似文献   
3.
Patients with mechanic ankle instability experience increased tibiotalar and subtalar joint laxity. However, in vivo joint kinematics in functional ankle instability (FAI) patients and lateral ankle sprain (LAS) copers, especially during dynamic activities, are poorly understood. Ten FAI patients, 10 LAS copers, and 10 healthy controls were included in this study. A dual fluoroscopic imaging system was used to analyze the tibiotalar and subtalar joint kinematics during stair descent. Five key poses of stair descent were analyzed. Kinematic data from six degrees of freedom were calculated utilizing a solid modeling software. The range of motion and joint positions in each degree of freedom were compared among the three groups. The tibiotalar joints of FAI patients and LAS copers were significantly more inverted than those of healthy controls during the foot strike (p = 0.016, = 0.264). The subtalar joints of FAI patients were significantly more anteriorly translated (pose 2, p = 0.003, = 0.352; pose 3, p < 0.001, = 0.454; pose 4, p = 0.004, = 0.334), inverted (pose 4, p = 0.027, = 0.234; pose 5,p = 0.034, = 0.221), and externally rotated (pose 4, p = 0.037, = 0.217; pose 5; p = 0.004, = 0.331) than those of healthy controls during the mid‐stance and the heel off. The FAI patients showed excessive tibiotalar inversion and subtalar joint hypermobility during stair descent. Meanwhile, the LAS copers maintained subtalar joint stability, and only showed excessive tibiotalar inversion in foot strike. These data provide insight into the mechanisms behind the development of FAI after initial LAS. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1860–1867, 2019  相似文献   
4.
5.
Many institutions in Japan perform PCI via the radial artery(TRI), due to the adility of TRI to improve the quality of life of patients. However, this procedure involves the significant problem of causing narrowing of the radial artery or occlusion by trans-radial approach.  相似文献   
6.
Hip fractures occur late in life following a substantial reduction in skeletal mass. If risk for such fractures could be predicted early, efforts to prevent excessive bone loss would be more successful and could be directed at the individuals most likely to be affected. With this objective in mind, we devised an approach to estimating the lifetime risk of a proximal femur fracture based on age and on current femoral bone mineral density, using population-based data from ongoing studies of osteoporosis and fractures among Rochester, Minnesota, women. Our calculations indicate that, at any given age, the lifetime risk of a proximal femur fracture rises as current bone density diminishes. At any given level of femoral bone density, lifetime risk rises with younger age and increasing life expectancy. While these trends seem robust, estimates of risk vary substantially with the assumptions that underlie the model. Consequently, these assumptions must be validated before our findings can be applied clinically to predict risk for individual patients.  相似文献   
7.
8.
9.
目的 探讨紫外线照射充氧(UBIO)对梭曼急性中毒家兔全血乙酰胆酯酶(AchE)活性的影响及对梭曼中毒后肺损伤的治疗作用.方法 家兔40只,随机分为正常对照组、中毒组、常规治疗组及UBIO治疗组各10只,于治疗后2h检测全血AchE 活性及进行动脉血气分析.收集支气管肺泡灌洗液(BALF),分析其中碱性磷酸酶(AKP)、酸性磷酸酶(ACP)活性.结果 中毒组AchE活性显著低于对照组(P<0.01),BALF中AKP及ACP活性高于对照组(P<0.01).经UBIO治疗后AchE活性升高,且明显高于中毒组及常规治疗组.与中毒组比较,UBIO治疗组中AKP及ACP活性显著降低(P<0.05),而动脉血pH值、PaO2及SaO2明显升高(P<0.05),PaCO2明显降低(P<0.05).结论 UBIO能提高全血AchE活性及减轻梭曼中毒后的肺损伤,因而可能是一新的治疗梭曼急性中毒的途径.  相似文献   
10.
Tissue engineering is an application for gene therapy that is in its infancy. We show that simple liposomal-mediated gene transfer could result in a potentially useful biological effect in the field of wound healing. cDNA encoding the 165 amino acid form of vascular endothelial growth factor complexed to commercially available liposomes was injected into rat skin 1 week before raising a random pattern 3 x 10 cm flap. The flap survival was enhanced by 14 percent, and was accomplished without accessing the arterial inflow of the territory. These results were statistically significant (p<0.002) and reproducible. No adverse effects were seen. Histological analysis of the angiogenesis localized much of the new vessel formation to the area around the hair follicles. Polymerase chain reaction amplification of extracted flap tissue confirmed the presence of the transgene.  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