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101.
目的:建立PCR—ELISA法检测附受体RNA。方法:提取20例银屑病病人和20例正常对照组血液单个核细胞标本中的总RNA,用双标记的PAF—R(Biotion与Digoxin标记)及β-actin(Biotin或Fluorescein标记)引物进行RT-PCR,用ELISA检测PCR产物,用传统的琼脂糖凝胶电泳对照。结果;ELISA法和琼脂糖凝胶电泳法对β-actin检测结果均为阳性;ELISA法检测PAF-R,20例病人标本均为阳性,20例对照组16例阳性;琼脂糖凝胶电泳法检测PAF—R,20例病人标本18例阳性,20例对照组16例阳性。结论:PCR-ELISA引物双标记法检测PAF—R操作简单,有较高的敏感性。  相似文献   
102.
We proposed a mathematical model to describe the early filling process of the left ventricle and applied the model toin vivo experiments. The solution of a second-order differential equation indicated that the pressure difference between the left atrium and ventricle during ventricular filling (PD) could be explained by a transient response, i.e. decremental oscillation, in an LCR circuit. Thereafter, we analysed the sequence of PD during vagal stimulation with two catheter-tip manometers in 12 anaesthetised dogs and evaluated changes in the parameters of the system under various haemodynamic conditions. The values of ωn and ξ were quite stable among beats within an episode of vagal stimulation, between episodes and even among dogs, despite the changes in haemodynamic variables. Pericardiotomy and partial discommunication of the mitral valve with the left ventricular free wall by cutting the mitral chordal tendons decreased ωn and increased ζ, mainly because of the increase in CLV. Occlusion of the coronary vascular beds with large numbers of microspheres increased ωn and decreased ζ, mainly because of the decrease in CLV. Mitral obstruction with an inflated balloon (increase in R) abolished the oscillatory changes and produced and exponential decay sequence of PD. In conclusion, both the logical and experimental approaches indicated that the sequence of PD could be considered as decremental oscillation in the LCR circuit and the parameters ωn and ξ could be good indices of the diastolic property of the left ventricle  相似文献   
103.
高血压病患者血清IGFⅡ的变化   总被引:3,自引:7,他引:3  
目的 :探讨胰岛素样生长因子Ⅱ (IGFⅡ )与高血压病 (EH)以及与高血压伴左室肥厚 (EH伴LVH)的关系。方法 :采用放射免疫分析 10 0例未治疗的EH患者和 5 0例正常人血清IGFⅡ水平。并用彩色多普勒诊断仪测定 10 0例EH患者的左心室重量 (LVM )。结果 :EH患者血清IGFⅡ水平明显高于正常人[(0 6 6± 0 35 )ng/ml:(0 4 4± 0 14 )ng/ml,p <0 0 1],EH伴LVH者IGFⅡ高于EH非LVH者 [(0 82± 0 4 0 )ng/ml:(0 5 4± 0 2 0 )ng/ml,p <0 0 1]。结论 :EH患者IGFⅡ水平升高 ,其升高程度与病情密切相关 ,IGFⅡ可能参与了EH心肌肥厚的形成  相似文献   
104.
Lee HH  Cha SC  Jang DJ  Lee JK  Choo DW  Kim YS  Uh HS  Kim SY 《Virus genes》2002,25(2):179-188
The immunity of a combined DNA vaccine of HSV-2 glycoproteins B2 (gB2) and D2 (gD2) genes in comparison to individual vaccines was studied with regard to protecting against the HSV infection. Two recombinant DNA vaccines of the pHS2-gB2 or pHS2-gD2 were constructed and formulated. The neutralizing antibody titers appeared higher in the B2:D2 gene cocktail-vaccinated mice than that of the individual B2 or D2 gene-vaccinated group alone, and the positive KOS control induced higher titer of the neutralizing antibody than combined or individual gene vaccines. The mock-immunized mice failed to induce enough. The ranks for the CTL activity and the protection rates against the lethal intravaginal challenge were shown as KOS>B2:D2 cocktail>D2>B2 gene vaccines. The vaginal external diseases in the B2:D2 or D-vaccinated mice were significantly reduced against the challenging dosages. The virus titers in the vaginal secretions of the vaccinated mice significantly reduced with time, and the B2:D2 gene vaccine decreased more than each individual vaccine alone. It can be concluded that the cocktailed vaccines are more effective in the humoral and cellular immune responses in the mice, and in the protection of the mice against the intravaginal challenging dosages when compared with individual gene vaccines. All the DNA vaccines failed to block the latent infection in sensory nerves.  相似文献   
105.
The perennial controversy about the safety of mercury in dental amalgams has adversely affected the availability and the quality of dental care. Chronic Hg(II) blood concentrations above 300 nM are known to alter function of the nervous system and the kidney. However, the effects of blood concentrations of 10 to 75 nM, far more common in the general population, are not clear and mechanisms of any effects are not known. The monocyte is an important potential target of Hg(II) because of its critical role in directing inflammatory and immune responses. In the current study we tested the hypothesis that concentrations of Hg(II) of 10 to 300 nM alter monocyte activity via a redox-dependent mechanism. Mitochondrial activity was used to establish inhibitory concentrations of Hg(II) following 6 to 72 h of exposures to THP1 human monocytic cells. Then subinhibitory concentrations were applied, and total glutathione levels and reactive oxygen species (ROS) were measured. Antioxidants [N-acetyl cysteine, (NAC); Na2SeO3, (Se)] and a pro-oxidant (tert-butylhydroquinone, tBHQ) were used to support the hypothesis that Hg(II) effects were redox-mediated. After 72 h of exposure, 20 microM of Hg(II) inhibited monocytic mitochondrial activity by 50%. NAC mitigated Hg(II)-induced mitochondrial suppression only at concentrations of greater than 10 microM, but Se had few effects on Hg-induced mitochondrial responses. tBHQ significantly enhanced mitochondrial suppression at higher Hg(II) concentrations. Hg(II) concentrations of 75 and 300 nM (0.075 and 0.30 microM, respectively) significantly increased total glutathione levels, and NAC mitigated these increases. Se plus Hg(II) significantly elevated Hg-induced total cellular glutathione levels. Increased ROS levels were not detected in monocytes exposed to mercury. Hg(II) acts in monocytic cells, at least in part, through redox-mediated mechanisms at concentrations below those commonly associated with chronic mercury toxicity, but commonly occurring in the blood of some dental patients.  相似文献   
106.
目的:探讨内皮细胞清除补体攻膜复合物(MAC)的途径及其清除动力学,方法:原代培养的人脐静脉内皮细胞以RH414荧光标记质膜双层,0℃组装亚溶剂量的MAC,37℃复苏后,LSCM实时监MAC沉积诱导的质膜囊泡化形成和胞吞,胞吐情况,流式细胞仪定量检测内皮细胞表面MAC抗原的清除情况,结果:MAC沉积后,内皮细胞有的质膜囊泡化形成,囊泡以胞吞和胞吐2种方式离开细胞,并以前者占优,37度条件下,内皮细胞清除表面MAC的半衰期约为5min。结论:内皮细胞可通过胞吞和胞吐2种机制清除细胞表面沉积的MAC,并以胞吞方式为主。  相似文献   
107.
108.
目的总结桡骨远端粉碎性骨折的外固定架治疗疗效。方法从1995年~2003年采用外固定架治疗桡骨远端粉碎性骨折46例,并进行随访。结果治疗后均随访1年,术后按Dienst评分,优良率为83.3%。结论外固定架固定牢靠,可早期活动腕关节,是治疗桡骨远端粉碎性、开放性骨折的有效方法。  相似文献   
109.
A veronal buffer extract of Salmonella typhi was used as the reference antigen and its corresponding rabbit antiserum as the reference antibody in crossed immunoelectrophoresis to analyze antibodies in sera obtained from typhoid patients and carriers. Four precipitating antibodies were regularly detected. Three were against antigens common to other gram-negative bacteria and one appeared to be typhoid specific. Of the three common antigens, one (antigen no. 7) formed a precipitin resembling in mobility and morphology the lipopolysaccharide antigen seen in crossed immunoelectrophoresis analysis of other gram-negative bacteria. The other (antigen no. 19) was heat labile and antigenically similar to the reported common antigen of Pseudomonas aeruginosa. The third (antigen no. 14), also heat labile, was present in members of the family Enterobacteriaceae but not the family Pseudomonas. The typhoid-specific precipitating antibody present in sera of most typhoid patients and carriers but not patients infected with nontyphoid salmonella was directed to a heat-labile, non-O, non-H, and non-Vi antigen (antigen no. 28), probably protein in nature.  相似文献   
110.
腺病毒载体介导的lacZ基因在NG细胞系及大鼠黑质的表达   总被引:1,自引:0,他引:1  
本实验用标记基因lacZ5型重组腺病毒(Ad5CMVlacZ)转染培养的NG细胞系,X-gal染色检测转染效率.在培养的NG细胞系,当病毒滴度为2×108时,转集率达到50%,当滴度为2×109时,转染率达100%,有较好的量效关系;固定病毒液度为1010,培养2~16h,细胞的转染率随时间延长而提高,有较好的时效关系。将Ad5CMVlacZ注射到大鼠黑质部位后,分别于注射后3~120d取脑、切片、X-gal染色,发现黑质局部从第7d开始有部分蓝染,第10d达高峰,注射局部感染率100%;90d时开始下降,持续至120d;纹状体等其它部位无蓝染.上述结果提示,腺病毒载体介导的标记基因可在培养的神经细胞系和中脑黑质部位高效表达,为进一步开展中枢神经系统退变性疾病尤其是帕金森氏病的基因治疗奠定基础。  相似文献   
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