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991.
以骨间背侧动脉为蒂逆行岛状皮瓣的应用解剖学   总被引:10,自引:2,他引:10  
在60侧灌注血管染料的新鲜成人上肢标本上,观察了骨间背侧血管在前臂背侧的起点、走行和分支,发现该动脉终末支在腕上2.5cm 水平,与骨间掌侧动脉背侧支之间有恒定的吻合支相连,并以此吻合支为蒂,设计了前臂骨间背侧血管逆行岛状皮瓣。  相似文献   
992.
本文重点讨论人体湿润新鲜尸体腰椎体椎间盘的粘弹性性质,实验在不同应变率下测定它的变形规律,以及椎间盘的蠕变,松弛特性,加载与卸载的变化。  相似文献   
993.
本文介绍大白鼠坐骨神经压迫症动物模型的制备和初步应用,以期为周围神经压迫综合症的深入研究提供一个较理想的动物实验模型。  相似文献   
994.
在介导体内外基因转移方面,脂质体已显示出许多优于病毒载体的特征.然而,有关脂质体介导造血细胞基因转移的报道很少.本文描述了脂质体介导双标志基因(Neo~R和Lac Z)在体外共转移进入人及小鼠原代造血细胞的研究.基因转移的效率通过X-gal染色及观察集落的形成来评价.结果显示,在存在G418的体系中,转导细胞能够存活并形成集落,而未转导细胞则不能存活.同时,转导阳性细胞能够被X-gal染成蓝色.其蓝染阳性细胞率在人及小鼠造血细胞于G418选择前分别为13.33± 2.68%和16.28± 2.95%.经G418选择启分别达到46.06±3.47%及43.45±4.1%,显著高于筛选前(P<0.01).提示,利用脂质体这一简单、安全的转导策略在原代造血细胞可获得高效的基因转移及稳定的表达.同时,共转导双标志基因进入造血细胞可用作高集转导阳性细胞.这一结论对于临床进一步探讨造血重建的生物学特征、追踪白血病的复发机制以及利用造血细胞作为靶细胞进行基因治疗的研究提供了实验依据.  相似文献   
995.
目的:评价剪切波弹性成像(shear wave elastography,SWE)测量育龄期健康未育女性宫颈杨氏模量值的可重复性。方法:由同一名接受过SWE检测培训的高年资医师于同一天不同时间点,前后2次对100名处于育龄期但未育的健康女性宫颈行剪切波弹性成像,测量时选取宫颈4个位点:内口前唇(anterior lip of the inner mouth,IA)、内口后唇(posterior lip of the inner mouth,IP)、外口前唇(anterior lip of the outer mouth,EA)及外口后唇(posterior lip of the outer mouth,EP),获取育龄期健康未育女性宫颈杨氏模量值。使用组内相关系数(interclass correlation coefficient,ICC)评价检查者内可重复性,同时绘制BlandAltman散点图评价测量一致性。结果:宫颈4个测量位点的前后2次测值均无统计学差异(P>0.05);宫颈IA、EA、EP处杨氏模量值的组内相关系数分别为0.828、0.785、0.768,提示组内可重...  相似文献   
996.
目的 探讨近端联合远端收肌管阻滞在全膝关节置换术患者术后镇痛和早期功能康复中的应用。方法 选取2019年1月至2020年12月在解放军总医院第六医学中心择期行单侧全膝关节置换术患者90例,按随机数字表法分为3组,每组30例。A组为对照组,于超声引导下行股神经联合腘窝上坐骨神经阻滞;B组为近端联合远端收肌管阻滞组,于超声引导下分别行收肌管近端和远端阻滞;C组为右美托咪定联合收肌管阻滞组,于超声引导下将罗哌卡因与右美托咪定混合液分别注射至收肌管近端和远端。比较3组患者术后6 h(T1)、12 h(T2)、24 h(T3)和48 h(T4)时静息VAS评分,术后T3和T4时运动VAS评分,48 h内羟考酮和氟比洛芬酯使用情况;以及术后24 h(T3)、48 h(T4)和72 h(T5)膝关节活动范围(ROM)和股四头肌肌力;记录3组患者术后首次直腿抬高≥10 cm时间,术后首次下床活动时间,术后7...  相似文献   
997.
Scanning electron microscopic observations on the structure of the body surface of various larval stages and young adults of Angiostrongylus cantonensis were made. The mouth opening of the first and second stage larvae closes in "Y" form until well developed young adult stage. There are two rows of 6 sensory papillae each around the mouth. With development of the worm, the papillae of the outer row gradually degenerated and could hardly be seen in adult worms. A pair of amphidial pores was present on the external side of lateral papillae of the inner row, being conspicuous in the fourth-stage larvae. There was one excretory pore on the ventral side of the anterior end. The copulatory bursa of the male worms began to develop in the third stage larvae and became well developed in the 25-day young adults. The processes of the development of copulatory bursa were described. The gonopore could be seen in the female worm as early as in the first-stage larvae but the anal pore appeared only in the fourth-stage larvae, both of them did not develop completely until the young adult stage of 11 day old (Figs. 1-18).  相似文献   
998.
The effects of the H2-receptor antagonists, cimetidine and famotidine, on the microsomal metabolism of [14C]lovastatin were investigated. Liver microsomes were prepared from control, phenobarbital- and 3-methylcholanthrene-pretreated rats and humans (male and female). Concentration-dependent inhibition of the metabolism of lovastatin (0.1 mM) was observed with cimetidine (0.1 to 1.0 mM). In contrast, famotidine at a similar concentration was a very weak inhibitor. The formation of 6'beta-hydroxy-lovastatin, the major microsomal metabolite of lovastatin, was similarly inhibited. The results suggest that in vivo metabolic interaction with concomitantly administered lovastatin is less likely with famotidine than with cimetidine. Phenobarbital pretreatment produced 58% stimulation in overall metabolism, whereas 3-methylcholanthrene pretreatment had no effect relative to control rats (5.4 nmol/mg protein/min). Liver microsomes from phenobarbital-pretreated rats produced 67% more of the 6'beta-hydroxy-lovastatin but 63-66% less of the 3'-hydroxy and 6'-exomethylene metabolites. Liver microsomes from 3-methylcholanthrene-treated rats also produced less 3"-hydroxy-lovastatin (49%) but similar quantities of the other two metabolites. 6'beta-Hydroxy-lovastatin was a major metabolite with human liver microsomes. Interestingly with these microsomes, hydroxylation at the 3'-position of the molecule was a negligible pathway and hydrolysis to the hydroxy acid form was not observed. The formation of 6'-exomethylene-lovastatin was also catalyzed by human liver microsomes (0.5 to 0.8 nmol/mg protein/min).  相似文献   
999.
<正> 应用多种方法对经络的循行路线进行了检测和显示,证明其行程与古典的经络路线基本一致,结果稳定,可重复。但是,显性感传的经络现象在人群中只占25%左右,而人群中大多数是属于隐性感传,应用生物物理学方法已观察到皮肤低电阻点(穴位)循  相似文献   
1000.
Objective To explore the characteristics of arrhythmogenic right ventricular cardiomyopathy (ARVC). Methods Seven patients with arrhythmogenic right ventricular cardiomyopathy and 34 members of three families were studied. All patients and family members underwent history collection, clinical examination, electrocardiogram (ECG), two-dimensional echocardiography (2-DE) and a signal averaging electrocardiogram. Programmed ventricular stimulation was performed in five patients. Results All patients and family members had normal morphologic characteristics and normal function of the left ventricular by 2-DE. Fourteen persons had abnormal findings indicating ARVC. Five had enlargement of the right ventricular with diffused hypocontractility, eight had thin and systolic bulging in the focal anterior wall with hypokinesia and one had bulging of the inferior wall. Twenty-five persons (seven patients and 18 family members) had abnormal findings in ECG. Positive ventricular late potential was recorded in 13 persons (six patients). Two to three monomorphic ventricular tachycardia (VT) with left bundle branch block (LBBB) configurations were induced in five patients. Ventricular fibrillation was induced in two patients during the electrophysiologic study (EPS). Five patients had very high pacing threshold and/or ineffective pacing in one or many regions of the right ventricle. Two members of one family died suddenly. One member was a dwarf with ARVC. Spontaneous VT with a left bundle branch block (LBBB) configuration was recorded in five patients, polymorphic VT with extremely short coupling interval in one, and premature ventricular complexes with LBBB configuration in 12 (six patients). Conclusion Our familial study strongly suggests that ARVC may be a hereditary disease and it is helpful in the diagnosis and detection of ARVC. The most common manifestations were abnormal structure and function of the right ventricle and abnormal ECG of repolarization and ventricular arrhythmia which originates from the right ventricle.  相似文献   
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