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31.
试尖对根管充填质量影响的研究 总被引:4,自引:0,他引:4
目的:了解试尖对侧向加压法根管充填质量的影响因素。方法:随机提取我院1998年10月至2004年12月所完成的根管充填病例的X线片1000例,按试尖与未试尖,分别对前牙、前磨牙和磨牙根管充填质量进行分析。结果:在482例未试尖根管充填病例中,前牙、前磨牙和磨牙的适充比例分别为46%、37%和23%,欠充为20%、29%和47%。超充为34%、33%和29%:在518例试尖病例中,前牙、前磨牙和磨牙的适充比例分别为68%、62%和51%,欠充为6%、12%和13%,超充为25%、24%和36%。结论:在侧向加压法根管充填中,试尖可明显改善充填质量。 相似文献
32.
磁珠耳穴贴压治疗偏头痛临床观察 总被引:9,自引:2,他引:7
目的比较磁珠耳穴贴压治疗与服用西药治疗偏头痛的疗效差异。方法将偏头痛患者200例随机分为磁珠耳穴贴压组(观察组)和西药组(对照组),比较其对头部疼痛改善情况。结果观察组总有效率94.6%,明显优于对照组的78.6%(P〈0.01)。结论磁珠耳穴贴压治疗偏头痛疗效肯定,总有效率优于西药治疗。 相似文献
33.
基于薄板样条和形状内容的医学图像非刚性配准方法研究 总被引:2,自引:0,他引:2
目的 针对医学图像非刚性点配准的现状,给出一种基于点特征的非刚性配准方法.方法 利用一种新的相似度测量方法--形状内容来解决两幅图像中点的对应关系,并利用点对应关系来估计非刚性映射函数.结果 利用薄板样条实现了医学图像的快速准确非刚性配准.结论 实验结果表明,上述方法获得了很好的配准效果. 相似文献
34.
虚拟现实互动技术在交叉韧带等长重建计算机辅助设计中的应用 总被引:3,自引:0,他引:3
目的 利用虚拟现实技术还原膝关节骨性结构在屈伸运动过程中的三维空间形态,为观测膝关节面交叉韧带附丽区的相对位置变化和进一步研究前、后交叉韧带等长重建最佳等长点提供计算机辅助设计新方法。方法 采用实验与计算机仿真相结合的方法,对新鲜人体膝关节标本进行屈伸运动实验,并通过激光三维扫描方法记录、计算膝关节的空间活动指标,然后重建膝关节计算机三维模型。通过实验中的空间活动指标控制此模型虚拟运动,再现膝关节各屈伸角度下股骨、胫骨和腓骨的空间位置。结果 计算机还原出各运动角度下膝关节骨性结构(股骨、胫骨及关节面)的空间形态,利用软件Geomagic的几何计算功能可分别测量模型中各个运动状态交叉韧带附丽区两点间的三维空间距离。讨论本研究方法可以真实地记录和再现膝关节三维运动过程,从空间结构上更精确、合理地寻找重建等长点,对膝关节交叉韧带手术重建有重要临床意义。 相似文献
35.
Dirk Mayer Wolfgang Dreher Dieter Leibfritz Daniel M Spielman 《Magnetic resonance in medicine》2007,57(5):967-971
A numerical simulation tool was developed to calculate the echo amplitudes of J-coupled resonances within a series of radiofrequency (RF) refocused echoes. The signal modulation due to J-coupling in rapid acquisition with relaxation enhancement (RARE) is suppressed only when the inverse of the pulse interval (tau) is large compared to both the chemical shift (CS) difference (Deltadelta) of the coupled spins and the coupling constant. In contrast, the echo amplitudes in ultrafast low-flip-angle RARE (U-FLARE) oscillate around a quasi-steady-state value that is greater than zero (neglecting relaxation and diffusion) even when Deltadelta > 1/tau. The flip-angle distribution over the measured slice caused by the use of Gaussian-shape slice-selective refocusing pulses further reduces the echo oscillations. When the pulse interval falls short of the fast pulse rate regime, spectroscopic U-FLARE provides an improved spatial impulse response in the phase-encoding (PE) direction compared to spectroscopic RARE. 相似文献
36.
37.
Shiro Saito Makoto Hata Ryuichi Fukuyama Kosuke Sakai Jun Kudoh Hiroshi Tazaki Nobuyoshi Shimizu 《International journal of urology》1997,4(2):178-185
Background Mutation converts the H-ras gene into an activated oncogene in about 10% of human bladder cancers. Codons 12 and 61 are the major "hot spots" for activation. A simple and accurate method to detect point mutations in these codons may be clinically useful for early diagnosis of bladder cancer.
Methods Bladder cancer samples from 50 patients, plus 10 samples of normal bladder mucosa, were analyzed for possible point mutation of the H-ras gene at either codon 12 or codon 61. The H-ras gene DNA segments that include these 2 codons were amplified by PCR methods, then the possible presence of a point mutation was evaluated at each codon by susceptibility of the respective DNA segments to digestion with the restriction enzyme and by dot blot hybridization assay. A bladder cancer patient who had an H-ras gene mutation was examined to see whether the mutation was also detectable in the cells released in the urine.
Results Definite or possible point mutations were found in 6 (1 2%) out of 50 bladder cancer patients, while no mutation was detected in normal mucosa. A point mutation could also be detected in cells isolated from the patient's urine sample.
Conclusion The prevalence of point mutations at codon 1 2 or codon 61 of the H-ras gene found in this study was similar to that previously estimated for human bladder cancer by DNA transfection assay. The method we have used for detecting point mutations of the H-ras gene provides a simple and highly accurate way to detect mutated cancer cells even in the urine. It may be clinically usable for early diagnosis of bladder cancer. 相似文献
Methods Bladder cancer samples from 50 patients, plus 10 samples of normal bladder mucosa, were analyzed for possible point mutation of the H-ras gene at either codon 12 or codon 61. The H-ras gene DNA segments that include these 2 codons were amplified by PCR methods, then the possible presence of a point mutation was evaluated at each codon by susceptibility of the respective DNA segments to digestion with the restriction enzyme and by dot blot hybridization assay. A bladder cancer patient who had an H-ras gene mutation was examined to see whether the mutation was also detectable in the cells released in the urine.
Results Definite or possible point mutations were found in 6 (1 2%) out of 50 bladder cancer patients, while no mutation was detected in normal mucosa. A point mutation could also be detected in cells isolated from the patient's urine sample.
Conclusion The prevalence of point mutations at codon 1 2 or codon 61 of the H-ras gene found in this study was similar to that previously estimated for human bladder cancer by DNA transfection assay. The method we have used for detecting point mutations of the H-ras gene provides a simple and highly accurate way to detect mutated cancer cells even in the urine. It may be clinically usable for early diagnosis of bladder cancer. 相似文献
38.
脐疗配合耳穴贴压治疗便秘26例 总被引:2,自引:0,他引:2
目的 探讨济疗配合耳穴疗法对便秘的疗效。方法 将50例便秘患随机分成两组,治疗组用济部药物贴敷配合耳穴贴压治疗;对照组单纯用于穴贴压治疗,所获数据采用t检验。结果 治疗组有效率96.15%,对照组有效率83.33%,经统计学处理,P<0.01,有显性差异。结论 济疗联合耳穴贴压治疗便秘疗效较单纯耳穴贴压效果好,且简单方便,无副作用。 相似文献
39.
Marc N. Branch 《Drug development research》1990,20(1):19-30
Food-deprived pigeons were trained to peck a key under either a three-component multiple random-ratio 5, random-ratio 25, random-ratio 125 schedule or a three-component multiple random-interval 10-sec, random-interval 30-sec, random-interval 125-sec schedule of food presentation. Following determination of acute effects of cocaine (1.0-13.0 mg/kg), are-sponse-rate-reducing dose was given before each daily session. Once performance under conditions of daily administration had become stable, other doses occasionally were substituted for the usual daily dose so that dose effects could be assessed. Tolerance, i.e., a rightward shift in the dose-effect curve was observed in all subjects. For subjects studied under the random-ratio schedules, however, the robustness of the tolerance usually was related to the schedule-parameter value; tolerance was great at lower random values. By contrast, subjects whose responding was maintained by random-interval schedules were less likely to show tolerance that was schedule-parameter dependent. The results also provide suggestive evidence that dose may be an important factor in determining effects of repeated cocaine exposure; repeated administration of larger doses may be less likely to result in tolerance than similar exposure to smaller doses. 相似文献
40.
对CT所见腰椎间盘突出的重新鉴别与治疗观察 总被引:1,自引:0,他引:1
目的:因临床发现有些经CT检查有腰椎间盘突出的患者,其症状体征与CT结果不符。对112CT阳性者根据症状体征进行重新鉴别。方法:将CT阳性者根据“三种试验”分为阳性、阴性两组,再选压痛点作注射治疗。结果:两组治疗结果阴性组优良率较高。结论:CT结果可供参考,但不能作临床考虑的主要依据。对腰椎间盘突出症的诊断与治疗要以症状体征为主 相似文献