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61.
简明心境量表(BPOMS)的初步修订   总被引:12,自引:8,他引:12  
迟松  林文娟 《中国心理卫生杂志》2003,17(11):768-770,767
目的 :修订并检验简明心境量表 (BPOMS)的信度和效度。方法 :对 886名大学生实施该量表 ,并对其中 74人间隔 9天评定重测信度。随机抽取 87名门诊初诊神经症患者进行BPOMS、抑郁自评量表(SDS)和焦虑自评量表 (SAS)的测查 ,评定效标效度。选取 87名年龄、性别和文化与病例组相匹配的正常个体为对照组填写BPOMS ,评定区分效度。结果 :BPOMS的重测信度系数在 0 40 6~ 0 664之间 ,α系数在0 70 5~ 0 890之间 ,具有较满意的信度。原量表共有 6个维度 ,本研究对BPOMS进行因素分析后提取了 5个维度 ,仍能够合理地解释该量表的结构。修订后BPOMS的“抑郁”维度与SDS、“紧张”维度与SAS的相关系数分别为 0 60 5和 0 60 2 (P <0 0 1) ,神经症组与对照组在BPOMS和各维度的得分均有显著性的差异 (P<0 0 1) ,说明BPOMS有良好的区分效度和效标效度。结论 :该量表具有良好的信效度 ,是测量个体心境状态简便易行的工具。  相似文献   
62.
冠状动脉支架抗压缩性能的有限元分析   总被引:5,自引:0,他引:5  
冠状动脉支架作为经皮穿刺冠状动脉成形术中保持病变血管畅通的核心器件。其对病变动脉壁的支撑作用如何是支架植入术成功的先决条件之一。依据冠脉支架抗压缩性能的实际测试原型,建立起对应的有限元模型,并利用此方法系统地研究了专利支架设计,其扩张尺度的不同和筋的尺寸变化对支架抵抗两平面压缩性能的影响。结果显示,随支架扩张直径的增大,其抵抗两平面压缩的作用减小,增加支架筋的宽度或厚度能够提高支架的抗压缩性能,且这两个方向尺寸的增加对提高抗压缩性能的作用相当。模拟与实验结果一致,表明有限元模拟可以在一定程度上替代支架原型测试工作。  相似文献   
63.
具有三层管壁结构组织工程血管支架的生物力学性能   总被引:2,自引:0,他引:2  
目的针对组织工程血管的体内培养技术路线,对所制备的具有三层管壁结构的组织工程血管支架的生物力学性能进行测试,并研究了壁厚对支架力学性能的影响,以保证后续的动物体内移植实验能顺利进行。方法采用涂敷,喷涂.滤沥的方法制备了具有三层管壁结构(多孔PLGA层.致密PU层.多孔PLGA层)的可降解组织工程血管支架,用自制的设备测试了其爆破强度和径向顺应性,并对血管支架进行了缝合强度的测试。结果所制备的厚度为0.295mm-0.432mm的三层结构血管支架的径向顺应性为3.80%/100mmHg-0.57%/100mmHg,爆破强度为160kPa~183kPa,缝合强度为0.63N/针~1.52N/针。结论支架的管壁厚度,尤其是中间层厚度,对支架的力学性能有重要影响。增大壁厚可导致径向顺应性急剧下降,爆破强度和缝合强度线性提高。在所制备的样品中,管壁厚度为0.295mm的支架其综合力学性能最优,可满足血管组织工程体内植入的力学性能要求。  相似文献   
64.
The relationship between the arterial blood pressure and the volume of the arteries within a segment of an extremity is nonlinear. The present paper shows how the flow and volume pulsations of the arteries within a limb segment can be simulated taking this property into account. An electrical model was constructed comprising one resistor and two voltage dependent ‘capacitors’, the latter corresponding to the pressure dependent elasticity, or compliance, of the arteries. Adequate simulations were obtained over a wide pressure range, which is impossible with linear models. The nonlinear, i.e. pressure dependent, relationship between the volume and pressure of arteries, observed under static conditions, must also be taken into consideration when studying pulsatile events with models whether mathematical or physical.  相似文献   
65.
The discharge characteristics of sacral visceral afferents supplying the urinary bladder, urethra, colon and anus to mechanical stimuli were analyzed in the anaesthetized cat. The stimuli used were passive distension (urinary bladder, colon), isovolumetric contraction (urinary bladder), movements of the urethral catheter and mechanical shearing stimuli (mucosal skin of the anal canal). (1) In total 245 afferent units which projected in the pelvic nerve were isolated from the sacral dorsal roots. From one of the following organs, urinary bladder, colon, urethra and anus 117 afferent units were activated. By these stimuli from the bladder, urethra and anus 122 afferent units could not be activated, and as far as tested also not from the colon; in 6 afferent units the classification was unclear. (2) Afferent units from the urinary bladder and the colon responded consistently to passive distension of the respective organ. The units from the urinary bladder showed graded responses at intraluminal pressures of about 10–70 mm Hg and responded also to isovolumetric contractions of the organ. The thresholds of the units from the bladder to passive distension and contraction varied from about 5 to 20 mm Hg intravesical pressure. (3) The afferent units from the urethra and the anus did not react or showed some weak phasic and irregular responses to distension and contraction applied to the urinary bladder or to distension of the colon. They were consistently excited by low threshold mechanical stimulation of the urethra and anus, respectively. (4) The axons from the bladder, urethra and anus were presumably myelinated (conduction velocity above 2 m/s) and conducted at 10.3±6.1 m/s (n=34, mean±SD), 26.3±9.3 m/s (n=13) and 9.5±5.1 m/s (n=37), respectively. The axons from the colon conducted at about 0.5 to 16 m/s (n=20), 13 of them conducting at less than 2 m/s. About 75% of the axons which could not be activated by mechanical stimulation of the visceral organs were presumably unmyelinated (conduction velocity below 2 m/s). (5) Some ongoing activity was found in 9 out of 26 afferent units from the anus but, with one exception, the afferent units from the bladder, urethra and colon were silent. (6) It is concluded that the pelvic afferent units from the urinary bladder, urethra, colon and anus consist of distinct populations with characteristic response patterns. There is no indication from this investigation that the urinary bladder is supplied by sacral afferents which are only recruited at high intravesical pressures during passive distension and isovolumetric contractions and which are possibly associated with pain.Supported by the Deutsche Forschungsgemeinschaft  相似文献   
66.
Summary The contractile properties of motor units (MUs) in two multi-tendoned forelimb muscles were investigated. In anesthetized cats single MUs of the extensor carpi ulnaris (ECU) and extensor digitorum communis (EDC) muscles were selectively activated by stimulation of cervical ventral root filaments. MUs were characterized by various tests including single twitches, series of tetanic contractions providing a tension-frequency relation and a fatigue test. They were classified by the parameters contraction time (CT, time-to-peak within unpotentiated single twitches) and fatigue-index (RB, according to Burke). The ECU muscle is composed of 38% type FR MUs (fast, fatigue-sensitive; CT<38 ms; RB<0.5), 35% type FR MUs (CT<38 ms, RB>0.5) and 27% type S MUs (slow; CT>38 ms, RB>0.5). 46% of the EDC MUs were classified as FF (RB0.25), 29% as FI (fast, intermediately fatiguable; 0.25<RB<0.75) and 25% as FR/S (fatigue-resistant, fast or slow; RB>-0.75). The latter group was devised since most MUs appeared as fast and the unequivocal presence of slow MUs could neither be demonstrated nor excluded. Normalized tension-frequency relations of fast ECU and EDC MUs were nearly identical and similar to those reported for fast MUs of other muscles. In contrast to this, the tension-frequency relation of slow ECU MUs has a different shape supporting the use of this function to distinguish fast from slow MUs. The distribution of different types of MUs is discussed with regard to the structure and function of the parent muscles and in relation to hindlimb muscles of comparable architecture. As revealed by comparison to EMG data gained in behaving animals (Fritz et al. 1985; Hoffmann et al. 1986, Botterman et al. 1985), the three muscles of the cat distal forelimb investigated so far seem to be adapted to different tasks: the EDC to rapid movements with a high proportion of type FF MUs, flexor carpi radialis to sustained contractions during the body support with a high proportion of fatigue-resistant MUs; the ECU which changes synergism between both muscles has an intermediate composition.  相似文献   
67.
目的:修订Griffith精神发育量表(0~7岁),并建立适合中国国情的常模。方法:采用对城市级别、年龄、性别、父亲职业等因素按比例分层随机抽样的方法,从山西省十二个城市共抽取了2022例0~7岁儿童,样本人群中上述几个因素的构成与山西省人口资料相吻合,由经过专门培训的测试员对抽样点当地的每个儿童进行单独测试,并填写测查量表。结果:年龄分组样本和总样本各分测验以及总发育商的均数都在100上下浮动,总发育商服从正态分布;项目分析显示,各分测验及总量表平均难度在0.5左右,鉴别指数0.62~0.78;对原量表个别项目的排序进行调整;测试者信度0.953,重测信度0.798~0.948,各分测验之间及分测验与总发育商之间相关系数在0.481~0.854之间,探索性因素分析的结果得到思维推理、知觉组织、意动因子三个因素,解释方差比率总计79.8%。结论:引进和修订后的Griffith量表具有较好的信度和效度,可用于评定儿童的智力水平,可以在山西省应用。  相似文献   
68.
This study compares changes in contractile properties, Parvalbumin content, and Ca2+-uptake by the sarcoplasmic reticulum (SR) of low-frequency stimulated rat and rabbit tibialis anterior (TA) muscles. Time to peak tension increased 1.8-fold in 35-day stimulated rabbit TA, while no change occurred in rat TA. Isometric twitch tension increased 2-fold in rabbit TA, but was unaltered in rat TA. Parvalbumin (PA) content was more than 90% reduced in rabbit TA, but only 60% in rat TA after 35 days. At this time, PA content of the stimulated rat TA was still higher than that of normal rabbit TA. Taking into account the suggested role of PA as a cytosolic Ca2+ buffer, its decrease could lead to an impaired free Ca2+-decay with a prolonged active state and a higher tension output during a single twitch. This would explain why chronic stimulation led to an increase in isometric twitch tension in rabbit TA, but not in rat TA. The 1.6-fold rise in half-relaxation time of 35-day stimulated rat and rabbit TA most likely resulted from a 50% reduced Ca2+-uptake by the SR, due to a still unknown modification of the Ca2+-transport ATPase.  相似文献   
69.
近乎完美量表中文修订版在初中生中的适用性   总被引:1,自引:0,他引:1  
目的:探讨近乎完美量表中文修订版在初中生中的适用性.方法:采用班级整群抽取,分为2个样本.对样本一的616名初中生施测近乎完美量表中文修订版、考试焦虑量表;对样本二的679名初中生施测近乎完美量表中文修订版、自尊量表、Beck抑郁问卷.结果:对样本一的数据进行探索性因素分析表明,各条目在所属因子的因子负荷为0.548~0.858,三个因子可解释总变异的54.44%;对样本二数据进行验证性因素分析为原量表的三因素结构(高标准因子、差异因子和秩序因子)提供了支持,拟合指数为:x2/df=6.653、GFI=0.907、CFI=0.901、RMSEA=0.066,模型拟合较好.利用两个样本的数据进行的信度分析表明,三个分量表的内部一致性系数分别为0.869、0.904和0.708.效标关联效度检验表明,高标准和秩序分量表均与自尊正相关(r=0.30、0.10,P<0.01或0.05),与抑郁负相关(r=-0.20、-0.12,P<0.01);高标准分量表与考试焦虑负相关(r=-0.13,P<0.01);差异分量表与自尊负相关(r=-0.57.P<0.01),与考试焦虑、抑郁正相关(r=0.34、0.78,P<0.01).结论:量表的信度和效度符合心理测量学要求.可以用于初中生的完美主义研究.  相似文献   
70.
焦虑敏感问卷中文版的信度和效度   总被引:1,自引:0,他引:1  
目的:翻译和修订焦虑敏感问卷,测试中文版的信效度。方法:翻译焦虑敏感量表,通过对中学生的三次测试,对量表的因素结构、信度和效度进行了检验。结果:修编的焦虑敏感问卷中文版通过探索性因素分析将原量表由36题缩减为15题,共包括三个因素:对生理唤醒的恐惧;对认知失控的恐惧;对社会评价的恐惧;三个因素的累积贡献率为52.29%,项目的因素负荷率在0.63~0.98之间;因素彼此之间的相关在0.37~0.53之间,因素与问卷总分之问的相关在0.72~0.84之间,因素内部的相关在0.68~0.78之间。问卷在各个因素上的内部一致性系数在0.73~0.78之间.分半信度在0.71~0.76之间,重测信度在0.70~0.78之间。结论:问卷的中文简化版在中学生中具有良好的信度和效度。  相似文献   
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