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21.
应用X衍射方法测定雷公藤两个化合物的晶体结构,并对影响固体熔点的结构因素进行分析。晶型(或空间对称群)、结晶溶剂、分子间作用力及分子构象的精细变化均可导致晶态物质的熔点变化。 相似文献
22.
Fabio Ghezzi Maurizio Serati Antonella Cromi Stefano Uccella Stefano Salvatore Paola Triacca Pierfrancesco Bolis 《International urogynecology journal》2006,17(4):335-339
The purpose of this study was to evaluate the outcome of tension-free vaginal tape (TVT) procedure in women with urodynamic stress incontinence diagnosed as having intrinsic sphincteric deficiency (ISD). The combination of a maximal urethral closure pressure <20 cm H2O and a Valsalva leak point pressure <60 cm H2O was considered as diagnostic of ISD. Subjects with detrusor overactivity on preoperative urodynamics were excluded. A total of 35 patients with both low closure pressure and leak point pressure were enrolled. Bladder perforation occurred in three (8.6%) cases. Postoperative urinary voiding difficulties occurred in nine (25.7%) women. Two patients underwent surgical detension of the tape, with complete resolution of urinary retention and no relapse of incontinence. Women with postoperative voiding dysfunction had a significantly lower detrusorial pressure at the peak flow on preoperative urodynamics compared to those who voided efficiently after TVT. The mean (range) follow-up time was 12.5 months (3–36). The objective cure rate for stress incontinence was 91.4%. Two of the three (66%) patients in whom the TVT procedure failed had a fixed urethra. De novo urge incontinence was found in five (14.3%) patients. 相似文献
23.
瞄准前沿以人为本全面提升医院的综合竞争力 总被引:3,自引:3,他引:0
介绍了医院创新工作思路和瞄准国际前沿,高起点培训专业技术人才,全面提升医院综合竞争力的主要做法及取得的成效. 相似文献
24.
人心肌肌钙蛋白I第2和第4个密码子同义突变对其在大肠埃希菌中表达的影响 总被引:1,自引:1,他引:0
目的 对人心肌肌钙蛋白I(cTnI)基因实行定点突变并进行原核表达,观察此突变对cTnI表达量的影响。方法 利用RT-PCR方法从人心肌细胞的总RNA中克隆出编码人心肌肌钙蛋白I的cDNA片段,设计引物将其第2和第4个密码子突变后插入原核表达载体形成重组体,并导人宿主菌BL21(DE3)中,经IPTG诱导表达,Ni-NTA树脂纯化后行Western blot鉴定,观察突变对cTnI表达的影响。结果 突变后的cTnI基因与对照组相比在大肠埃希菌中得到高效表达,经纯化可获得电泳单点纯的cTnI蛋白。结论 成功克隆了cTnI基因,所设计的同义突变可促进cTnI在大肠埃希菌中的高效表达。 相似文献
25.
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
26.
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
27.
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
28.
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
29.
30.
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