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71.
The effects, on operant feeding, of injection into the lateral cerebral ventricle of 50 μmoles CaCl2, 4 mmoles D-glucose, 2-deoxy-D-glucose (2DG) or xylose, or NaCl, have been studied in five pigs. All the sugars and CaCl2 were given in 1 ml of normal saline. Each of the sugar solutions produced transient drinking. Only CaCl2 and 2DG significantly increased food intake during the hour following injection. The results show that the mechanism by which the pig responds to intracerebroventricular 2DG is similar to that of the rat and different from that of the sheep.  相似文献   
72.
Although little is known about the neuroanatomical basis of skin conductance orienting in intact normal humans, the limited literature on animals and humans with neurological and clinical disorders implicate prefrontal, temporal/amygdala, and pons brain areas in mediating skin conductance orienting. This study relates area of these structures using magnetic resonance imaging techniques to skin conductance orienting responses in 17 normal humans in order to test hypotheses that larger area of these excitatory structures will be associated with more orienting responses. Left and right hand skin conductance orienting was significantly associated with left and right prefrontal area (r = .44-.60), area of the pons (r = .43-.54), and left but not right temporal/amygdala area (r = .47-.53). No relationships were observed with areas thought to be unrelated to skin conductance activity (cerebellum, nonfrontal cortical area), medial prefrontal cortex, or the third ventricle. This appears to be the first study relating brain structure to skin conductance orienting in intact normal humans. Although preliminary at the present time, these results implicate prefrontal, pons, and temporal/amygdala areas in the mediation of skin conductance orienting in normal humans.  相似文献   
73.
犬21只,经左冠脉内注射麦角新硷诱发冠脉痉挛后随机静滴生理盐水(对照组)或等量盐水溶的巯甲丙脯酸(治疗组),观察1小时。心电图显示治疗组的异常ST段下降和严重室性心律失常明显少于对照组;冠脉造影显示治疗组痉挛血管支数及狭窄程度均少于和轻于对照组;左室造影和超声心电图显示治疗组的左室收缩末和舒张末容积小于对照组,EF值或△D大于对照组,AA/EA小于对照组;血流动力学参数表明治疗组左室收缩压,平均肺  相似文献   
74.
Isolated single myocytes were prepared from myocardium of developing ventricular aneurysms and from myocardium within the scar of chronic ventricular aneurysms. The morphology and function of the individual cells were compared. The cells from developing aneurysms were rod-shaped, with a distinct sarcomeric structure, but did not contract even in the presence of high calcium concentrations. The sarcomere length was significantly higher than that of cells from chronic aneurysms and approached the theoretical point at which no contraction can occur. Cells from chronic aneurysms were either rod-shaped and contractile, or rounded due to hypercontracture of the myofilaments. Electron microscopy of cells from developing aneurysms confirmed the presence of elongated sarcomeres, a loss of the actin-myosin interdigitation, and damage to the contractile proteins which was particularly evident in the thin filaments. Cells with similar characteristics have also been isolated from a ruptured, ischaemic papillary muscle. These changes, which are due either to ischaemia or to overstretching of cells, may account for the weakness of the wall of developing aneurysms and be a cause of rupture or enlargement.  相似文献   
75.
Summary Two hundred twenty five patients with intracranial lesions underwent diagnostic and therapeutic stereotactic surgery during the period 1978–1985. In the first 98 cases target coordinates were determined by transferring the information from the CT images to the standard stereotactic films. In the remainder, a simple, CT adapted stereotactic system has been used. Operations were as a rule performed under local anaesthesia. Positive histological diagnosis using paraffin embedding was achieved in 96% of the patients (biopsy success rate). Therapeutic procedures included abscess and cyst aspiration, cyst shunting, interstitial (Ir 192) or intracavitary (Y 90) irradiation and ventriculocisternostomy. Stereotactic surgery implied a refinement of the eventual therapeutic management in 90% of the cases. Transient neurological deficit occurred in 5.7% of the patients and there were three deaths (mortality rate 1.3%). Infection or other complications were not seen. The rationale and indications for non-functional stereotaxis are discussed.  相似文献   
76.
Summary We have characterized the muscarine receptors in bovine tracheal and left ventricular membranes using 3H-dexetimide/pirenzepine and 3H-dexetimide/AF-DX 116 competition studies. Pirenzepinc exhibited low (M2) affinity binding to both preparations; K d was 590 nM in left ventricle and 463 nM in trachea. AF-DX 116 exhibited high (M2) affinity binding to left ventricle (K d = 95.6 nM); in tracheal membranes it bound with high (M2) affinity (K d = 40.7 nM) to 74% of the receptors and with low (M3) affinity (K d = 2.26 M) to 26% of the receptors. It is concluded that bovine tracheal muscle membranes contain a heterogeneous population of muscarine binding sites, the majority having M2 (heart) subtype characteristics and being located on the smooth muscle membranes; a minority having M3 (exocrine gland) subtype characteristics and presumed to be located in submucosal glands. This is the first report of high affinity binding of AF-DX 116 to non-cardiac peripheral muscarine receptors. Send offprint requests to A. F. Roffel at the above address  相似文献   
77.
目的 调查功能性单心室患儿的健康相关生存质量(HRQOL),比较其与健康人群之间的差异。方法 对2002-2018年在上海儿童医学中心诊断为功能性单心室的113名2~18岁患儿及其家长进行横断面分析。采用中文版儿童生存质量测定量表(PedsQL)4.0普适性量表和3.0心脏模块的自评表和家长报告表,通过独立样本t检验比较功能性单心室组与健康组的普适性量表得分,采用单因素方差分析比较不同年龄段普适性量表中家长报告表得分差异。通过Kruskal-Wallis H检验分析不同年龄段心脏模块差异。结果 功能性单心室组的自评表和家长报告表得分在总分、生理、心理社会、情感、社会和学校方面均低于健康组,差异均有统计学意义(自评表:t=6.823、7.850、5.825、4.260、4.817、7.621,家长报告:t=7.641、8.589、6.459、5.823、6.206、7.381,P<0.05),并且学龄前患儿的生存质量得分偏低(F=4.090, P<0.05)。在心脏模块中,自评表的感知身体外貌方面,8岁以上患儿得分明显降低(H=8.812,P<0.05)。在自评表和家长报告表的治疗焦虑方面,8岁以下患儿得分偏低(H=6.045、14.702,P<0.05)。 结论 与健康儿童相比,功能性单心室患儿的HRQOL明显下降,因此需要对其HRQOL进行相关干预及评估。  相似文献   
78.
目的 :建立便于推广、功能齐全、价廉的三维医学图像重建系统及进行三维重建。方法 :利用目前较先进的数码摄片技术和自行编制的软件系统 ,对层距 1.0 mm的人体头部断面共 2 4 0层进行侧脑室的三维重建 ,同时对头部整体行三维重建以其进行相对定位和比较。结果 :重建后的侧脑室可和头部进行参照显示 ,行旋转、透明处理和不同方向的任意剖割。结论 :较以 CT、MRI断面图像重建的模型增加了轮廓的准确性和器官内组织的鲜明色彩  相似文献   
79.
In secondary mitral regurgitation, the concept that the mitral valve (MV) is an innocent bystander, has been challenged by many studies in the last decades. The MV is a living structure with intrinsic plasticity that reacts to changes in stretch or in mechanical stress activating biohumoral mechanisms that have, as purpose, the adaptation of the valve to the new environment. If the adaptation is balanced, the leaflets increase both surface and length and the chordae tendineae lengthen: the result is a valve with different characteristics, but able to avoid or to limit the regurgitation. However, if the adaptation is unbalanced, the leaflets and the chords do not change their size, but become stiffer and rigid, with moderate or severe regurgitation. These changes are mediated mainly by a cytokine, the transforming growth factor‐β (TGF‐β), which is able to promote the changes that the MV needs to adapt to a new hemodynamic environment. In general, mild TGF‐β activation facilitates leaflet growth, excessive TGF‐β activation, as after myocardial infarction, results in profibrotic changes in the leaflets, with increased thickness and stiffness. The MV is then a plastic organism, that reacts to the external stimuli, trying to maintain its physiologic integrity. This review has the goal to unveil the secret life of the MV, to understand which stimuli can trigger its plasticity, and to explain why the equation “large heart = moderate/severe mitral regurgitation” and “small heart = no/mild mitral regurgitation” does not work into the clinical practice.  相似文献   
80.
心血管参数对动脉中压力和流量的影响   总被引:2,自引:0,他引:2  
本文从建立心室-血管优化耦合模型出发,通过求解优化耦合所对应主动脉根部的压力和流量所满足方程,详细讨论动脉中压力和流量随心血管参数的变化规律,所得结果与血液循环系统的生理事实一致。  相似文献   
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