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1.
Miconazole and econazole, two fungicide imidazole derivatives, completely inhibited growth of Trypanosoma cruzi (Tulahuen strain) at concentrations of about 20 muM. Culturing of T. cruzi in the presence of lower doses of imidazole derivatives produced: decrease of 5,7-diene sterol content in epimastigotes (including ergosterol); disappearance of the nuclear chromatin, vacuolization and decrease in the electron density of the cytoplasm; selective surface alterations as revealed by an increased response to wheat-germ- and phytohemagglutinin. At variance with the effect of miconazole on Candida (De Nollin et al. (1977) Antimicrobial. Agents Chemother. 11, 500-513), miconazole and econazole, under the experimental conditions used, did not increase the rate of hydrogen peroxide generation by T. cruzi.  相似文献   
2.
胶乳凝集法与速率散射比浊法检测血清C反应蛋白的比较   总被引:1,自引:0,他引:1  
目的 探讨胶乳凝集法与速率散射比浊法检测C反应蛋白(CRP)的优越性。方法分别采用胶乳凝集法和速率散射比浊法检测35例病人血清和26例健康体检者血清CRP。结果速率散比浊法的灵敏度、临床符合率显著高于胶乳凝集法(P<0.01)。结论速率散射比浊法是一种较好的CRP定量方法,值得推广。  相似文献   
3.
检测18例体外循环紫绀型先天性心脏病手术病人术前,术中及术后3,8天外周血血小数量和 附,聚集功能,探讨体外循环对血小板质和量的影响。结果显示,血小板数量和聚集功能在术后显著下降并持续至术后8天,血小板粘附功能显著下降,术后3天恢复。提示体外循环气血界面,人工材料非内皮表面可导致血小板激活,粘附,聚集面在量消耗,数量和功能显著下降。  相似文献   
4.
The immunodiagnosticum for this test was prepared extempore by mixing blue color dyed latex beads (1% suspension) with equal volume of diluted anti-teliospore serum. This test was considered to be better for the detection of solubilized teliosporic antigens over intact teliospores of Karnal bunt. The teliosporic antigens solubilized using sonication and detergent extraction were used for the standardization of the test by optimizing the dilution of latex bead suspension and determining the detection limits. For determining the sensitivity of test, antigen concentration kinetics analysis was performed by adding 15 µl of antibodies sensitized latex beads to 15 µl of different concentrations of solubilized antigens on glass slide. The detection limit of this test was 7.5 µg solubilized teliosporic antigens equivalent to 750 teliospores and suitable for single seed analysis. Small agglutinin formation with solubilized antigen of Puccinia recondita and T. barclayana interpreted on the basis of partial cross reactivity of immunodignosticum with these pathogens. However, no cross reactivity was found with teliosporic antigen(s) of spores of Curvularia lunata, Ustilaga tritici, Helminthosporium sativum, Ustilaginoidea vircns and Alternaria triticina.  相似文献   
5.
A subcellular fraction enriched in erythrocyte membranes has been isolated from rhesus monkey erythrocytes infected with Plasmodium knowlesi. Infected cells were lysed by centrifugation through a zone of hypotonic buffer and membranes isolated by equilibrium density gradient centrifugation in the same tube. The purified membrane fraction was shown to include the erythrocyte surface membrane by several methods: electron microscopy, identification of Coomassie Blue stained erythrocyte membrane proteins, identification of band 3 with a monoclonal antibody, and identification of radioiodinated cell surface proteins. The resulting ghosts were shown to be specifically reactive with monkey sera against the variant surface antigens of P. knowlesi by indirect immunofluorescence and membrane agglutination. No reactivity was seen with a monoclonal antibody (13C11) against the intracellular schizont surface. A number of metabolically labelled parasite proteins were enriched in this membrane function, including peptides of 277, 208, 173, 153, 134, 109, 80, 60 and 48 kDa and the variant surface antigens of variable molecular mass (180-207 kDa). These proteins were distinct from the major parasite proteins of total infected erythrocytes and isolated merozoites. The major glucosamine labelled glycoprotein of the internal schizont (230 kDa) was not found in this fraction. Moreover, no fragment of this parasite glycoprotein was found in this membrane fraction, indicating that no part of this molecule is transported to the erythrocyte surface. In contrast, the variant antigen of P. knowlesi, known to be on the erythrocyte surface, could be readily identified as peptides unique to specific cloned parasite lines. We propose that the other nine parasite proteins found within this membrane fraction represent a starting point for the identification of other parasite proteins transported to the surface membrane of the infected erythrocyte.  相似文献   
6.
用杂交瘤技术建立了6株能稳定分泌抗阴道毛滴虫单克隆抗体的细胞株,选取其中3株进行了分析。3株单抗的效价分别是:ⅣA12B1和ⅣA22B1为250000ⅡB2A1为1250000。ⅣA12B1和ⅡB2A为IgG3抗体,ⅣA2281为IgGl抗体。位点分析及免疫酶染色发现,ⅣA12B1和ⅣA22B1抗同一抗原决定簇,所针对的抗原主要分布于膜上;ⅡB2A1针对的抗原主要分布于胞浆中。3株单抗针对的抗原均为糖蛋白。特异性试验发现,这3株单抗与人白细胞、阴道上皮细胞、白色念珠菌、大肠杆菌及人毛滴虫均无交叉反应。用制备的单克隆抗体,建立了试断滴虫性阴道炎的胶乳凝集试验(LAT)。研究表明,LAT是一种敏感、特异、简单和快速的方法。  相似文献   
7.
A slide latex agglutination (SLA) assay was developed for rapid screening for Clostridium perfringens type A enterotoxin (CPE). SLA specifically detected CPE added to buffer or normal feces (sensitivity limit of 1 μg CPE/g feces). Using clinical fecal samples from C. perfringens food poisoning cases, a strong correlation was shown between (1) SLA results and results from other CPE assays and (2) between SLA results and illness status.  相似文献   
8.
C-reactive protein (CRP) was assessed in pediatric serum samples using different commercial latex reagents, which were analyzed for species origin of the coating antibodies, homogeneity and density of the latex particles, and prozone agglutinating capacity. All reagents correctly agglutinated the positive and negative control sera. The antibodies coating the particles differed with regard to species origin: one was coated with rabbit, one with horse and goat, one with horse, goat, rabbit and swine, while the reference reagent had horse, goat and rabbit antibodies.Only the monospecies specific antibody-coated latex showed obvious prozoning; this reagent also had the smallest and most homogenous latex particles and showed the most clear-cut reactions. False agglutination was observed at 7–26% according to quantitation with the spot immunoprecipitate assay, which compared favorably with radial immunodiffusion measurements. The lowest percentage of false readings was noted for the rabbit antibody-coated particles; the highest for the reagent with particles coated using antibodies from 4 different species.No reagent had satisfactory precision for the low positive sera between 10 and 40 mg CRP/1.  相似文献   
9.
ABSTRACT: Efforts were made to disrupt and solubilize human sperm cells and to evaluate the product for its content of infertility antibody-related antigens. In the procedure that was developed, a well-washed sperm sample is treated with 0.1 M dithiothreitol for 60 min, followed by trypsin at 0.1 mg/ml for 30 min, and then by soybean trypsin inhibitor. A mixture of DNAses I and II are added. After centrifuging, the resuspended pellet (RP) and the final supernatant (FS) show several degrees of cellular breakdown. Immunological evaluation was done with a strongly positive human serum containing sperm-head antibody. From the inhibition of sperm agglutination, we could conclude that the desired soluble antigen was obtained in the FS fraction.  相似文献   
10.
In our laboratory we encountered problems interpreting the standard Friberg test. After an incubation period of four hours we could not interpret the test in 52 per cent of cases due to a high number of immobile spermatozoa and debris in the supernatant used as antigen in this test. By shortening the incubation period to two hours we could objectively interpret 76 per cent of cases. The applicability of the test was further improved by modifying the preparation of the antigen. Instead of using the supernatant of diluted semen, we "filtered" the motile sperm by means of the sperm penetration meter of Kremer. The capillary tube of the penetration meter was filled with virgin serum and incubated for one hour. After a four hour incubation this test could be applied in 80 per cent of cases, and after a two hour incubation period in all the cases. The reliability of this test was compared with the standard Friberg, the Kibrick and the Franklin-Dukes tests. The modifications did not alter the reliability of the test.  相似文献   
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