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101.
杭州地区8516例孕中期妇女产前筛查回顾性分析   总被引:2,自引:0,他引:2  
目的分析杭州地区孕中期妇女运用甲胎蛋白(AFP)和游离绒毛膜促性腺激素β亚基(Free-βhCG)进行胎儿先天缺陷产前筛查的结果;并据此修正两筛查指标的孕周中位数值。方法对杭州地区孕14~20w的妇女进行产前AFP和Free-βhCG的检测。胎儿先天畸形由染色体核型分析、B超检查确诊,或经引产证实。应用非线性加权回归求得本地区两筛查指标的中位数,并计算中位倍数值进行分布拟合。比较标化前后检测效果。结果8516例受检孕妇,共筛查出唐氏综合征3例、爱德华综合征2例,神经管畸形7例,其他胎儿异常17例;杭州地区孕中期妇女AFP及Free-β-hcG中位数比欧洲妇女分别高18%和14%;用修正后的中位数重新分析,孕中期假阳性率降低。结论血清AFP、Free-βhcG联合检测,可作为杭州地区孕中期妇女产前筛查优选项目。而根据地域人群的差异,对Mu ltiCalc软件内嵌中位数进行修正后更适于杭州地区孕中期妇女的产前筛查。  相似文献   
102.
We describe two sibs with tetraectrodactyly and oligomeganephronic renal hypoplasia. The parents were unaffected. This syndrome of apparently autosomal recessive origin appears to be the first Mendelian form of the acrorenal developmental field defect identified so far. © 1992 Wiley-Liss, Inc.  相似文献   
103.
目的:探讨前臂后皮神经营养血管远端蒂筋膜皮瓣修复手部软组织缺损的临床效果。方法:对18例手部创伤性软组织缺损创面采用带前臂后皮神经营养血管远端蒂筋膜皮瓣进行修复,其中机器绞伤11例,压砸伤5例,电锯伤2例,皮瓣面积最大为12cm×8cm,最小7cm×5cm。结果:17例皮瓣完全成活;1例皮瓣边缘部分坏死,经清创换药痊愈。术后随访6~12个月,皮瓣质地良好,外观满意。结论:前臂后皮神经营养血管远端蒂筋膜皮瓣切取简便、成功率高,是修复手部软组织缺损的理想供区。  相似文献   
104.
We studied the changes in the anti-oxidant capacity of tissues, such as heart, liver, and blood in male and female rats, as a parameter for evaluating oxidative stress after either a prolonged (210 min) or an exhausting bout of swimming. Furthermore, we also investigated exercise-induced changes in the electrophysiological properties, measured in vitro, of papillary muscle fibres. Small decreases of anti-oxidant capacities after prolonged exercise [0.10 (SEM 0.04) in heart, 0.43 (SEM 0.19) in liver, 0.22 (SEM 0.05) in blood] and greater decreases after exhausting exercise [0.23 (SEM 0.04) in heart, 0.90 (SEM 0.29) in liver, 0.34 (SEM 0.04) in blood] were found in tissues from the male rats. For the female rats, similar changes were found only in the blood [0.11 (SEM 0.07) and 0.35 (SEM 0.06) for prolonged and exhausting exercise, respectively]. Liver and heart anti-oxidant capacity remained unchanged after prolonged exercise, while after exhausting swimming it underwent a decrease almost the same as found in the male rats, though the swimming time to exhaustion (endurance capacity) was much greater [706 (SEM 10) min and 444 (SEM 32) min for the females and males, respectively]. The duration of the action potential, recorded from papillary muscle fibres, underwent changes related to the decreases in heart anti-oxidant capacity. In fact, the action potential duration (APD) was shorter only in preparations from the male rats after prolonged exercise, but in all preparations after exhausting exercise. After such exercise, the APD was similar for the male and female rats [37.1 (SEM 3.4) ms and 37.0 (SEM 3.6) ms, respectively]. Such a pattern was independent of stimulation frequency, since it was found substantially unchanged when the frequency was increased from 1 to 5 Hz. We concluded that the different susceptibilities to the effects of physical exercise, exhibited by tissues from these male and female rats might have been related to different capacities to oppose oxidative stress effectively.  相似文献   
105.
The left ventricular subendocardial and subepicardial layers of six perfused rabbit hearts were tested for enzymatic and non-enzymatic antioxidant defences and for lipid peroxidation. The subendocardium showed significantly lower catalase activity and contents of non-protein thiol compounds and vitamin E associated with a higher degree of lipid peroxidation. The activities of Cu,Zn- and Mn-superoxide dismutases, glutathione reductase, -glutamylcysteine synthetase and -glutamyl transpeptidase showed no significant transmural differences, and Se-independent glutathione peroxidase activity was not detectable in either layer. Comparable results were observed in another group of six unperfused rabbit hearts. In five H2O2-perfused rabbit hearts, lipid peroxidation was higher, and myocardial creatine phosphokinase activity lower, in the subendocarium than in the subepicardium. In this group, only the subendocardium had significantly higher lipid peroxidation levels than the control hearts. Thus, a lower antioxidant capacity and a greater oxidative stress are present in the rabbit subendocardium. These findings could provide insight into the problem of subendocardial vulnerability to free radical-mediated processes, such as occurs in ischaemia-reperfusion injury.  相似文献   
106.
This paper explores properties of discrete processes in which a pursuer seeks a target that is moving at constant velocity r that is a fixed proportion of the speed of the pursuer. The pursuer is subjected to proportional angular homeostasis, so chosen that the number of steps per circuit is small. The orbits relative to the target may assume any of four forms: polygons that reverse their sense an infinite number of times; or polygons that after a finite number of reversals ultimately come to have an integer numbers of sides; or have a rational numbers of sides; or have an irrational number of sides that densely fill an annulus. None of the polygons is regular. In the parameter space, the boundary line between the first of these sets and the other three has a somewhat bizarre pattern and may possibly be fractal, but no proof is forthcoming. Unlike the pattern with a stationary target, there may be a set or catchment of diverse values of the speed ratio, r, and the correction coefficient, b that all result in figures of some specified number, n, of sides (although with vertices in differing locations). Catchments have been found for only those polygons that have the winding number of 1. The implications are discussed that this property has for the genetic coding of biological traits that are countable. Some attention is also paid to the relevance of polygons with few sides to ontogenic growth when the correction coefficient is cyclically arc- or time-dependent. © 1993 Wiley-Liss, Inc.  相似文献   
107.
目的:观察同型半胱氨酸(Hcy)对心肌线粒体电子漏及自由基生成的影响,以及观察牛磺酸的拮抗效应。方法: 分离大鼠心肌线粒体,超声波破碎线粒体制备亚线粒体,纯化制备猪心肌线粒体琥珀酸细胞色素C还原酶(SCR)重组体。分别用Hcy和/或牛磺酸共同孵育心肌线粒体、亚线粒体、SCR;用化学发光法测定H2O2- 及O2- 生成;并用滤膜抽滤法观察线粒体膜牛磺酸转运体的性质及Hcy对牛磺酸转运功能的影响。结果: Hcy呈浓度依赖性地刺激大鼠心肌线粒体、亚线粒体氧自由基生成及SCR电子漏增加,牛磺酸自身不影响心肌线粒体、亚线粒体及SCR氧自由基生成,但呈浓度依赖性地抑制Hcy诱导的线粒体、亚线粒体及呼吸链重组体氧自由基生成。线粒体膜上存在Na+依赖性的牛磺酸转运体,Hcy呈浓度依赖性地抑制牛磺酸转运体对牛磺酸的转运功能。结论: 牛磺酸抑制Hcy刺激的线粒体呼吸链电子漏增加及氧自由基生成。线粒体膜上存在Na+依赖性的牛磺酸转运体,Hcy抑制线粒体膜上牛磺酸转运体对牛磺酸的转运功能。  相似文献   
108.
Stature estimation based on hand length and foot length   总被引:1,自引:0,他引:1  
This study was carried out to estimate the relationship between hand length, foot length and stature using multiple linear regression analyses based on a sample of male and female adult Turks residing in Adana. Measurements of hand length, foot length and stature were taken from 155 adult Turks (80 male, 75 female) aged 17-23 years. The participants were students of the Medical Faculty of Cukurova University. A multiple linear regression model was fitted to the observed data. Stature was taken as the response or dependent variable, hand length and foot length were taken as explanatory variables or regressors. All possible (simple and multiple) linear regression models for each of males, females and both genders together were tested for the best model. The multiple linear regression model for both genders together was found to be the best model with the highest values for the coefficients of determination R2 = 0.861 and R2adjusted = 0.859, and multiple correlation coefficient R = 0.928.  相似文献   
109.
This study assessed the reach to grasp movement and its adaptive response to a perturbation of object size. In blocked trials, subjects (n = 12) were instructed to reach 35 cm to grasp and lift a small- (0.7 cm) or large-diameter (8 cm) cylinder. Under an unconstrained condition (condition 1), no instructions as to the type of grasp to adopt were given. Subjects thus naturally used a precision grip (PG) for the small cylinder and whole hand prehension (WHP) for the large cylinder. Under condition 2, subjects were instructed to utilize a PG for grasps of both the large and small cylinders. For condition 3, the instruction was to use WHP irrespective of object size. Kinematic organization was determined with analysis of the recordings of active markers placed on the wrist, thumb, and three fingers. For condition 1 the results showed a temporal arrangement of both components (transport and manipulation) which differed from that of conditions 2 and 3. In perturbed trials, illumination shifted from the small to large cylinder or vice versa. With condition 1, subjects automatically switched from one grasp to another with no or little increase of movement duration. This was generally achieved by an earlier temporal setting of peak wrist deceleration. For conditions 2 and 3, where a change of aperture was required, movement duration was prolonged without adaptation of earlier transport component parameters. It is concluded that the adaptive responses to a change of distal patterning also affect the organization of the proximal component. Assessment of grasps constrained by instructions may lead to interpretations of central control of the reach to grasp movement which differ from those obtained by assessing more natural prehensile patterns.  相似文献   
110.
Summary The effects of two levels of protein intake on muscle performance and energy metabolism were studied in humans submitted to repeated daily sessions of prolonged exercise at moderate altitude. For this purpose, 29 healthy males, were exposed to seven successive stages of ski-mountaineering at altitudes between 2500 and 3 800 m, and to an isocaloric diet (4000 kcal·day–1, 16760 kJ·day–1) with either 1.5g·kg–1·day–1 (C group,n =14), or 2.5 g·kg–1·day–1 (PR group,n =15) protein intake. Measurements made after the ski-mountaineering programme did not show any change in body mass. The peak torque during maximal isometric voluntary contraction (MVC) of the quadriceps muscle was unaffected by the repeated exercises, whereas the endurance time at 50% MVC was decreased in PR subjects (–26.8%,P<0.001). Increased levels of both free fatty acids (+147%,P<0.001) and glycerol (+170%,P<0.001) observed in C subjects would suggest that lipolysis was enhanced after the repeated exercise. The plasma amino acid pattern was altered after completion of the ski-mountaineering programme; the plasma concentration of the three branched-chain amino acids (BCAA) was significantly decreased in C subjects, whereas the higher level of protein intake (PR group) greatly minimized the exercise-induced decrease in serum BCAA.  相似文献   
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