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   2605篇
  免费   195篇
  国内免费   41篇
耳鼻咽喉   39篇
儿科学   42篇
妇产科学   16篇
基础医学   304篇
口腔科学   58篇
临床医学   397篇
内科学   261篇
皮肤病学   24篇
神经病学   138篇
特种医学   74篇
外科学   478篇
综合类   319篇
预防医学   73篇
眼科学   281篇
药学   190篇
  2篇
中国医学   127篇
肿瘤学   18篇
  2024年   4篇
  2023年   17篇
  2022年   36篇
  2021年   109篇
  2020年   72篇
  2019年   51篇
  2018年   71篇
  2017年   79篇
  2016年   86篇
  2015年   82篇
  2014年   167篇
  2013年   165篇
  2012年   138篇
  2011年   145篇
  2010年   114篇
  2009年   110篇
  2008年   120篇
  2007年   122篇
  2006年   104篇
  2005年   104篇
  2004年   70篇
  2003年   76篇
  2002年   64篇
  2001年   50篇
  2000年   43篇
  1999年   44篇
  1998年   39篇
  1997年   36篇
  1996年   46篇
  1995年   50篇
  1994年   42篇
  1993年   39篇
  1992年   30篇
  1991年   27篇
  1990年   26篇
  1989年   17篇
  1988年   24篇
  1987年   25篇
  1986年   23篇
  1985年   27篇
  1984年   19篇
  1983年   15篇
  1982年   15篇
  1981年   15篇
  1980年   18篇
  1979年   19篇
  1978年   10篇
  1977年   10篇
  1976年   11篇
  1975年   4篇
排序方式: 共有2841条查询结果,搜索用时 314 毫秒
1.
刘俊  华自森  李诚诚  许静 《陕西中医》2020,(12):1759-1762
目的:探讨补阳还五汤重用伸筋草治疗脑梗死后痉挛型偏瘫的作用。方法:收集脑梗死后痉挛型偏瘫患者共88例,分为两组,对照组44例,西医治疗加康复训练和补阳还五汤治疗; 研究组44例,西医治疗加康复训练及补阳还五汤重用伸筋草治疗。比较治疗前后患者患侧上下肢肌张力、临床疗效、NIHSS、日常生活能力Barthel指数以及上下肢运动功能和不良反应发生率。结果:治疗后,两组患者患侧上下肢肌张力≤1级者占比均升高,且研究组中≤1级者占比均高于对照组,组间比较有统计学意义(P<0.05)。两组临床疗效等级分布和总有效率比较,差异有统计学意义(P<0.05)。治疗后两组患者NIHSS评分均降低,且研究组NIHSS评分低于对照组,治疗后两组患者Barthel指数和患侧上下肢FMA评分均升高,且研究组均高于对照组,组间比较有统计学意义(P<0.05)。两组不良反应发生率比较,差异无统计学意义(P>0.05)。结论:补阳还五汤重用伸筋草能够显著降低患者患侧上下肢肌张力,改善临床疗效和神经功能缺损,提高患者日常生活能力和患侧运动功能,且安全性良好。  相似文献   
2.
Intraoperative and postoperative free flap monitoring by means of oxygen tension measurement was carried out in 11 patients. We used an invasive flexible microcatheter that allowed for measurement of oxygen tension in all types of free flaps. Two cases of the measured flaps were buried free flaps which do not allow monitoring by clinical assessment. All flaps monitored in this study survived. One case of displacement of the microcatheter occurred. In one patient, the tissue pO2 monitor successfully detected early vascular thrombosis with subsequent reoperation and salvage of the free flap.  相似文献   
3.
Heparin-induced Extracorporeal LDL-Precipitation (HELP) is an effective procedure for the elimination of both plasma LDL and fibrinogen. In 10 adult patients with severe type II hyperlipoproteinemia, a single HELP treatment of 3 1 plasma led to an acute decrease in the average plasma viscosity (PV) from 1.30 to 1.1 mPas. At the same time, an even more marked decrease in the mean erythrocyte aggregation rate from a pathological value of 7.9% to a value of 3.7% (normal range less than 5%) was observed. Long-term studies on five patients demonstrated a lasting improvement in these two haemorheological variables. The acute rheological changes were also accompanied by an improvement in polarographically determined muscle oxygen tension. Mean oxygen tension values measured in both the m.biceps brachii and the m.tibialis anterior in five patients before and after a single HELP treatment increased from 30 +/- 4 to 37 +/- 7 mmHg and from 27 +/- 2 to 31 +/- 3 mmHg respectively. These results may provide an explanation for the rapid improvement in patients' clinical symptoms such as angina pectoris and in stress electrocardiogram which have been observed during HELP therapy.  相似文献   
4.
The melt agglomeration process of lactose powder with hydrogenated cottonseed oil (HCO) as the hydrophobic meltable binder was investigated by studying the physicochemical properties of molten HCO modified by sucrose stearates S170, S770 and S1570. The size, size distribution, micromeritic and adhesion properties of agglomerates as well as surface tension, contact angle, viscosity and specific volume of molten HCO, with and without sucrose stearates, were examined. The viscosity, specific volume and surface tension of molten HCO were found to be modified to varying extents by sucrose stearates which are available in different HLB values and melt properties. The growth of melt agglomerates was promoted predominantly by an increase in viscosity, an increase in specific volume or a decrease in surface tension of the molten binding liquid. The agglomerate growth propensity was higher with an increase in inter-particulate binding strength, agglomerate surface wetness and extent of agglomerate consolidation which enhanced the liquid migration from agglomerate core to periphery leading to an increased surface plasticity for coalescence. The inclusion of high concentrations of completely meltable sucrose stearate S170 greatly induced the growth of agglomerates through increased specific volume and viscosity of the molten binding liquid. On the other hand, the inclusion of incompletely meltable sucrose stearates S770 and S1570 promoted the agglomeration mainly via the reduction in surface tension of the molten binding liquid with declining agglomerate growth propensity at high sucrose stearate concentrations. In addition to being an agglomeration modifier, sucrose stearate demonstrated anti-adherent property in melt agglomeration process. The properties of molten HCO and melt agglomerates were dependent on the type and concentration of sucrose stearate added.  相似文献   
5.
A recently introduced setup to measure the dynamic interfacial tension of expanding drops was used to compare the adsorption behaviour of a series of lipids at the electrified water∣dichloroethane interface. Phospholipids with saturated carbon chains of different length (DMPC, DPPC, DSPC, DAPC, DBPC), an unsaturated phospholipid (DOPC) and an ethanolamine (DSPE) were compared. It was found that the adsorption decreases with increasing chain length. Also, the increase of the flow rate reduces the degree of adsorption effectively. On the timescale of the experiments, the DSPE, DAPC and DBPC adsorption showed no potential dependence, whereas the adsorption of DOPC was stronger than that of the saturated lipids. Adsorption was modelled using the Langmuir adsorption isotherm; the potential dependence of adsorption is discussed.  相似文献   
6.
7.
We compared data from 243 patients with episodic migraine (EM) and 132 patients with chronic daily headache (CDH). We divided the matter group into those with tension-type headache only (CDH Type 1) and those with headaches having migrainous features (CDH Types 2+3) and compared each with the EM group and all three groups with one another. CDH Type l patients differed from those in the other groups by virtue of gender (more often male) and mean age at headache onset (older). The CDH Types 2+3 and EM groups differed only in that the former were more likely to have undergone a brain-imaging study. These data suggest that CDH Type 1 may represent a distinct headache syndrome, while CDH Types 2+3 closely resemble episodic migraine.  相似文献   
8.
A method to evaluate the three-dimensional (3-D) geometry of the human gastrointestinal wall may be valuable for understanding tissue biomechanics, mechano-sensation and function. In this paper we present a magnetic resonance imaging (MRI) based method to determine rectal geometry and validation of data obtained in three volunteers. A specially designed rectal bag was filled in a stepwise manner while MRI and bag pressure were recorded. 3-D models of curvatures, radii of curvature, tension and stress were generated and the circumferential and longitudinal strains were calculated. The computed bag volumes corresponded to the infused volumes. A pronounced bag elongation and decrease in wall thickness was observed during the bag filling. The spatial distributions of the biomechanical parameters were distinctly different between individuals and non-homogeneous throughout the rectal wall due to its complex geometry. The average tension and stress increased as a function of infused volume and circumferential strain. The present study provides a method for characterizing the complex in vivo 3-D geometry of the human rectum. The non-homogenous spatial curvature distribution suggests that simple estimates of tension based on pressure and volume do not reflect the true 3-D biomechanical properties of the rectum.  相似文献   
9.
关节镜下改良张力带固定治疗髌骨骨折患者的康复护理   总被引:6,自引:1,他引:5  
对38例新鲜髌骨骨折患者行关节镜直视下骨折复位,改良张力带固定,术前和术后给予及时有效的功能康复和护理指导,取得满意的效果。平均随访18.6个月,骨折平均愈合时间7.5周,所有病例愈合良好,无并发症出现。关节镜治疗髌骨骨折为髌骨骨折提供了一种新的治疗方法。应针对其解剖特点制订科学、有效的护理方法。  相似文献   
10.
PTEN与基质金属蛋白酶在胃癌组织中的表达及意义   总被引:8,自引:3,他引:5  
目的:探讨PTEN与基质金属蛋白酶(MMP)在胃癌组织中的表达、相互关系及意义。方法:应用免疫组化SP技术检测80例胃癌组织中PTEN、MMP2和MMP9表达,同时检测20例正常对照组胃粘膜中PTEN表达。结果:胃癌组织中PTEN高表达率35/80(43.8%)显著低于对照组20/20(100. 0%)(P<0.01);PTEN表达与胃癌分化程度、浸润深度、淋巴结转移和肿瘤分期显著相关;胃癌组织中 MMP2、MMP9阳性表达率分别为41/80(51.3%)、29/80(36.3%),与胃癌浸润深度、淋巴结转移和肿瘤分期显著相关;PTEN与MMP2、MMP9表达显著负相关,与病人预后相关,Kaplan-Meier生存曲线分析显示PTEN高表达者术后累计生存率显著高于低表达者,PTEN高表达者术后3年、5年生存率显著高于低表达者;MMP2、MMP9阳性表达者术后累计生存率显著低于阴性表达者,MMP2、MMP9阳性表达者术后3年、5年生存率显著低于阴性表达者。结论:胃癌组织中PTEN表达显著减少,PTEN 与MMP2、MMP9表达显著负相关,PTEN可能通过调控胃癌组织MMP2、MMP9表达,抑制胃癌的浸润和转移,影响病人的预后。  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