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121.
Qian Y Lanjuan L Jianrong H Jun L Hongcui C Suzhen F Xia Y Shuhong Y 《The International journal of artificial organs》2003,26(6):507-513
Artificial liver support system (ALSS) has been used to treat hepatic failure and has significantly decreased the mortality. TECA hybrid artificial liver support system (TECA-HALSS), which combines the hollow fiber bioreactor with a plasma exchange circuit, was used to assess the efficacy, safety and feasibility in treating severe hepatitis patients. The hybrid artificial liver support system (HALSS) consists of a bioreactor containing more than 5 x10(9) porcine hepatocytes and plasma exchange device. Fifteen patients with severe hepatitis were treated with this hybrid system. All patients experienced a reduction in symptoms such as fatigue, abdominal distention or ascites. After each treatment serum total bilirubin decreased markedly while prothrombin activity increased. There were ten patients whose progress of hepatocyte necrosis was stopped after HALSS treatment, and finally they recovered completely. One patient received liver transplantation after HALSS therapy and survived. No serious adverse events were noted in the fifteen patients. 相似文献
122.
Heterogeneity of hepatitis delta antigen 总被引:10,自引:0,他引:10
Hepatitis delta antigen (HDAg) is the only known protein encoded by the hepatitis delta virus (HDV). Two HDAg species of different sizes have been detected in the sera and livers of the infected humans, chimpanzees, and woodchucks, even though only one RNA species was previously identified in most of the HDV strains. To study HDAg heterogeneity, we took advantage of the fact that a single base mutation at nucleotide 1015 (C to U), which results in an amber termination codon in the HDAg open reading frame (ORF), eliminates a unique Ncol restriction enzyme site. We screened various HDV cDNA clones and detected sequence heterogeneity of the HDAg-coding region on the basis of the presence or absence of the Ncol site. Five delta hepatitis patients were examined. In every patient, two types of HDAg-coding sequence were detected at nucleotide 1015: one which contains a C and results in an ORF encoding a delta antigen of 214 amino acids, and the other which possesses a U and results in an amber termination codon and a truncated HDAg species of 195 amino acids. The in vitro translation products of these two ORFs comigrated with the two HDAg species from the patient's plasma on SDS polyacrylamide gels. Polymerase chain reaction (PCR) amplification of the HDV RNA from some patients' sera and subsequent sequencing showed several additional mutations in the HDAg-coding region. These mutations are independent of the C or U nucleotide change at the site of the amber termination codon.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
123.
目的:在钙化大鼠主动脉血管平滑肌细胞上观察血管紧张素-(1-7)[Angiotensin-(1-7)]对钙化的影响及其信号通道。方法:用β-磷酸甘油制备钙化的大鼠血管平滑肌细胞,再以血管紧张素-(1-7)、血管紧张素Ⅱ、血管紧张素Ⅱ 血管紧张素-(1-7)、选择性蛋白激酶A(PKA)或蛋白激酶C(PKC)抑制剂等干预,通过Von Kossa染色及检测钙含量、碱性磷酸酶活性、骨钙素浓度和Cbfa1 mRNA表达来探讨血管紧张素Ⅱ对钙化的影响及其信号通道。结果:血管紧张素-(1-7)抑制钙化大鼠血管平滑肌细胞的钙含量、碱性磷酸酶活性(P>0.05)、骨钙素浓度和Cbfa1 mRNA表达(P<0.05),也抑制血管紧张素Ⅱ对血管平滑肌细胞的钙含量、碱性磷酸酶活性、骨钙素浓度和Cbfa1 mRNA表达的促进作用(P<0.05);血管紧张素-(1-7)提高血管平滑肌细胞内cAMP浓度(P<0.05),PKA抑制剂可阻断血管紧张素-(1-7)对钙化血管平滑肌细胞的钙含量、碱性磷酸酶活性、骨钙素浓度和Cbfa1 mRNA表达的抑制作用(P<0.05)。结论:血管紧张素-(1-7)可抑制β-磷酸甘油诱导的血管平滑肌细胞钙化,并拮抗血管紧张素Ⅱ促进的血管平滑肌细胞钙化;这些效应与cAMP-PKA-Cbfa1信号途径有关。 相似文献
124.
应用细胞原位杂交技术,观察经重组小鼠白细胞介素-19(IL-1β)处理后的体外培养的新生1d大鼠中脑黑质神经元c-jun基因的表达.结果显示,培养的黑质细胞多为酪氨酸羟化酶阳性神经元,IL-1β可诱导体外培养的黑质神经元c-junmRNA表达,高水平的表达出现在IL-1β处理后2~4h。说明IL-1β有兴奋黑质神经元的作用,并提示黑质神经元上可能存在IL-1β受体. 相似文献
125.
乳腺癌ER,PR状态与细胞超微结构变化的形态定量分析 总被引:1,自引:0,他引:1
用免疫组化PAP法检测30例乳腺癌雌激素受体(ER)和孕激素受体(PR),从中选取ER、PR阳性者(E^+P^+)6例,阴性者(E^-P^-)5例作透射电镜观察,对部分细胞器连接的变化进行形态定量分析。结果E^-P^-组癌细胞内线粒体、粗面内质网及溶酶体的含量明显高于E^+P^+组,且差异有显著性(P<0.05,0.01,0.01);E^-P^-组细胞间的桥粒及镶嵌连接有减少趋势,但差异无显著性 相似文献
126.
食管癌三维适形放射治疗疗效的Meta分析 总被引:6,自引:0,他引:6
目的分析三维适形放射治疗技术(3-DCRT)治疗食管癌的疗效和放射毒性反应。方法检索国内有关数据库查找符合条件的临床随机对照试验,采用Meta分析方法,对国内公开发表的有关3-DCRT治疗食管癌的临床随机对照试验研究文献进行综合分析,在RevMan4.2.7软件中统计分析相应的研究指标。结果有8项独立的临床随机对照试验研究进入了本次meta分析。3-DCRT组的近期疗效,1、2、3年局控率及1、2、3年生存率均优于对照组(p〈0.01)。两组毒副反应的差异无统计学显著性意义。结论3-DCRT治疗食管癌的近期疗效优于常规放射治疗方法,远期疗效和毒副反应有待进一步观察随访和研究。 相似文献
127.
Objective: To investigate the ultra structure of amelanotic melanocytes (AMMC). Methods: The hair follicles obtained from normal human scalp by 0.50% collagenase type V treatment were washed with 0.1mol/L phosphate buffer salt (PBS). Hair-follicle cell suspensions were prepared by trypsin treatment and cultured in melanocyte medium. Remaining keratinocytes were removed by differential trypsinization. 100μg/ml geneticin was used to eliminate the contaminating fibroblasts. At third passage, the cells were trypsinized, and then washed in phosphate-buffered saline and processed for transmission electron microscopy. Results: Under transmission electron microscope, the cultured cells showed round or oval shape, with single large nuclear and the karyotheca were double deck. There were obvious euchromosome within the nucleus, and sparse heterochromosome. There were various organelles in the cytoplasm, including plentiful melanosomes with nearly similar size, mitochondria, rough endoplasmic reticule (RER) and ribosome. The electron density granules in most of the melanosomes disposed along concentric circularities. Golgi apparatus in the cells was inconspicuous. Conclusion: The ultra structure of AMMC from human hair follicles is different from that of epidermal melanocytes, and these characteristics determine the functional immature of AMMC. 相似文献
128.
129.
人Nanog基因的克隆及其在COS-7L细胞中的表达 总被引:2,自引:0,他引:2
目的 :克隆人Nanog基因 ,构建其真核表达载体 ,并观察其在哺乳动物细胞COS 7L中的表达。方法 :利用HE2 93细胞的人基因组DNA为模板 ,以LA PCR技术 ,扩增Nango的基因 ,定向克隆到带Flag标签的pCMV载体中 ,测序后 ,挑选序列正确的真核表达质粒pFlag Nanog转染COS 7L细胞。用抗Flag标签的抗体 ,进行Westernblot和间接免疫荧光染色法检测Nango蛋白的表达。结果 :从人基因组DNA中克隆到序列正确的Nanog全长编码序列。所构建的Nanog质粒在COS 7L细胞中获得高效表达。结论 :人Nanog基因的克隆、真核表达载体的构建及在COS 7L中的表达均获得成功 ,为进一步研究其功能 ,尤其是探讨其在神经干细胞中的作用奠定了基础。 相似文献