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11.
An antiserum to the purified porcine outer acrosomal membrane (OAM) was raised in female Balb/c mice and was characterized by means of an indirect ELISA. The hyperimmune serum reacted selectively with the acrosomal cap of the sperm head and showed an extremely good cross reactivity with bull and human spermatozoa when assayed by indirect immunofluorescence. Immunoelectron microscopy using the protein A-gold method further confirmed the specificity of the anti-OAM-antiserum for the OAM. In an effort to identify the OAM antigens recognized by the hyperimmune serum and to analyse the extent of cross reactivity on a molecular level, the SDS-extractable proteins were separated by SDS-PAGE, transblotted and immunoprinted using an 125J-conjugated anti-mouse-antibody. To facilitate functional and structural analysis of distinct OAM-proteins monoclonal antibodies were generated by hybridization of mouse myeloma cells with the splenocytes of female Balb/c mice immunized with the purified OAM. One fusion resulted in about 100 anti-OAM-antibodies secreting hybridoma cultures, of which about 30% showed cross reaction with human and bull spermatozoa. Four stable cell lines were selected for this study secreting antibodies directed against the outer acrosomal membrane of boar spermatozoa. Whereas the polyclonal immune mouse serum stained the entire acrosomal cap, the four hybridoma antibodies generated a patch-work-like immunofluorescence pattern over the acrosome. HPLC-ELISA of the solubilized OAM revealed first information on the nature of the corresponding membrane antigen.  相似文献   
12.
Objective: To further explore the mechanism of congenital pyrimidine 5'-nucleotidase I deficiency. Methods; The samples were collected from the family members of a patient with P5'N- I deficiency. The enzyme activities were measured by UMP method and the enzyme proteins were quantified by ELISA while the morphology of peripheral blood cells was observed. Results: The enzyme contents reduced as their enzyme activities decreased in the family especially in four members. There was a significant positive correlation(r =0. 955) between the activity and the content of P 5'N- I . The count of the stippling cell was varied in the family. Conclusion.- One of the reasons for congenital P5' N- I deficiency might be the deficiency in the enzyme content. The morphology of peripheral blood erythrocyte may be an assistant diagnotic index. The P5'N- I activities and contents were measured simultaneously may be a effective method in clinic diagnosis.  相似文献   
13.
目的 探讨在ELISA检测HBsAg试验中,标本混入WBC后,WBC的粘附现象对试验结果的干扰。方法 观察WBC粘附现象对测定结果的干扰情况,以及血浆中WBC含量与干扰程度的关系,同时采用增加洗涤次数的方法对抗WBC粘附的效果观察。结果 标本混入WBC,WBC在反应板内发生粘附。WBC的中性粒细胞含过氧化物酶对试验结果造成干扰;标本中单位体积WBC含量与WBC的粘附量不成正比,但WBC的有效粘附数与OD值直接相关,粘附量越多,OD值越高;且WBC的粘附经洗涤10次也未能完全洗脱。结论 在ELISA检测HBsAg工作中应注意WBC对试验产生的非特异性干扰,采用多种方法防止WBC的混入。  相似文献   
14.
An indirect enzyme-linked immunosorbent assay (ELISA) for the detection of hexoestrol (HES) was developed, optimized and validated for the analysis of HES in pork. Many parameters, such as the volume ratio of solution A and solution B, colour developing time, pH value, incubation time, the volume ratio of the standard solution and diluted antiserum, blocking solution, blocking condition, coating solution and coating condition were studied and optimized in the paper. The regression equation of the final inhibition curve is y = - 0.3345x + 1.4955, R2=0.9913. The linear range is 0.1-8.1 ng/ml, and the IC50 is 0.671 ng/ml. The specificity of the assay was evaluated by the cross-reactivity rates of six compounds, of which two structurally related compounds had a relatively higher cross-reactivity rate of 25% and 6%. HES was added into a pork sample at 5 ng/g level and then the sample was extracted. The recovery is between 49.6% and 79.2%, and the variation coefficient is 0.164.  相似文献   
15.
利用酶联免疫吸附测定法,酶标β-羟基β-甲基-戊二酸单酰铺酶A(HMG-CoA)还原酶抑制剂Compactin抗体,定向筛选血脂调节剂。从青霉M-8614菌株发酵液中分离到M-8614A。该物质理化性质及波谱解释表明与Mevastatin为同一物质。 M-8614菌株用亚硝酸盐等诱变剂处理,从诱变株MH-2688发酵液中分离到MH-2688B。该物质理化性质及波谱解释表明与Lovastatin为同一物质。  相似文献   
16.
用快速双抗体夹心ELISA检测囊虫病人血清中的循环抗原,其阳性率为67.5%;正常人血有的假阳性率为5.33%;包虫、肝吸虫和弓形虫病人血清的交叉反应率分别为6.9%、7.5%和12.5%。结果表明.该法与常规双抗体夹心ELISA相比具有较为敏感、快速、稳定和节省血清、试剂用量的优点,但其特异性有待进一步提高。用快速双抗体夹心ELISA和间接型ELISA检测第1至10疗程囊虫病人血清中的循环抗原和抗体,表明检测循环抗原考核囊虫病人的治疗效果优于检测抗体  相似文献   
17.
斑点—酶联免疫吸附试验检测卡氏肺孢子虫   总被引:1,自引:0,他引:1  
应用完整的卡氏肺孢子虫包囊作抗原,以4×10^7/ml包裹点样,作斑点-酶联免疫吸附试验检测肺印片卡氏肺孢子虫包囊阳性的BALB/c小鼠血清20份,同时检测包囊阴性的小鼠血清20份,结果除一份小鼠血清IgG阴性反应外,均为阳性反应,阳性率为95%;而正常对照血清全为阴性反应。另外,检测了3份纤支镜刷检物中包囊阳性的病人血清,均为阳性反应;50例健康孕妇血清的检查,抗体阳性率为12%。  相似文献   
18.
Elevation of plasma thioredoxin levels in HIV-infected individuals   总被引:3,自引:0,他引:3  
Thioredoxin (Trx), a ubiquitous protein intimately involvedin redox and protein disulfide reductions, has been shown tobe released from cells and to have cytokine-like activities.In addition, Trx has been implicated in the redox regulationof immunological responses and shown to be deficient in tissuesfrom AIDS patients. In studies presented here, plasma Trx levelswere measured by ELISA in plasma samples from HIV-infected individuals(n = 136) and HIV-negative controls (n = 47). To account forthe release of Trx into plasma due to hemolysis, the Trx measurementswere corrected according to the level of hemoglobin in the plasmasample. Data presented show that, in contrast to tissue Trxlevels, corrected plasma Trx levels are significantly higherin HIV-infected individuals than in controls (P < 0.0001).Furthermore, {small tilde}25% of the HIV-infected individualsstudied have plasma Trx levels greater than the highest levelfound in controls (37 ng/ml). Detailed multiparameter FACS analysisof peripheral blood mononuclear cells (PBMC) from the infectedindividuals demonstrates that those with higher plasma Trx levels(37 ng/ml or greater) tend to have lower overall CD4 counts.In addition, increases in plasma Trx levels correlate with decreasesin monochlorobimane staining (indicative of lower intracellularglutathione levels in PBMC) and with changes in surface antigenexpression (CD62L, CD38 and CD20) that occur in the later stagesof HIV infection. These correlations suggest that elevationof plasma Trx levels may be an important component of advancedHIV disease, perhaps related to the oxidative stress that oftenoccurs at this stage.  相似文献   
19.
白细胞介素-18在特发性血小板减少性紫癜中作用的研究   总被引:1,自引:0,他引:1  
目的 探讨白细胞介素-18(IL-18)与特发性血小板减少性紫癜(ITP)发病的关系,研究其在ITP发病中的作用及临床意义.方法 酶联免疫吸附测定(ELISA)测定血浆IL-18,对36例ITP患者和正常对照组血浆IL-18的水平进行分析.结果 ITP组血浆IL-18含量为(538.31±111.33)pg/ml,正常对照组血浆IL-18含量为(489.44±49.07)pg/ml.IL-18含量与血小板数量呈显著性负相关(r=-0.395,P<0.05).结论 ITP发病时患者血浆中的IL-18水平比正常对照组明显升高,IL-18与ITP发病密切相关.  相似文献   
20.
An enzyme-linked immunosorbent assay (ELISA) was used to measured IgG antiboody titers againt a synthetic peptide whose sequence was derived from the glycine-alanine repeating region of Epstein-Barr virus nuclear associated antigen 1 (EBNA-1). Antibody titers were determined in sera from 15 normal subjects, sera from 21 normal male siblings of X-linked lymphoproliferative syndrome (XLP) patients, from 20 XLP patients comprising a total of 42 samples, and ten samples before and ten samples after gamma-globulin therapy in ten patients with XLP. Data analysis demonstrated that while there are differences between the ELISA and ACIF, they appear to measure a similar response as demonstrated by their correlation coefficient (0.77) and the GMT to EBNA observed by both methods. No cross-reactivity of cytomegalovirus antibodies to the EBNA-1 peptide was observed by immunobv using adsorption against AD-169 infected MRC-5 cells.. However, non-specific binding was observed if samples were not pre-incubated in a 10% goat serum PBS-Tween 20 solution. This pre-treatment removed the non-specific binding that falsely elevated GMT in approximately 15% of both normal and XLP samples in ELISA. The ELISA system appears to be a sensitive, reproducible and objective test that may be useful for assessing the antibody responses of patients to the EBNA-1 protein.  相似文献   
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