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41.
Formalin-fixed paraffin-embedded hippocampal sections of brains with early-onset and late-onset Alzheimer's disease were studied immunohistochemically with antisera against cathepsin D and cathepsin B. In addition to the staining of neuronal perikarya, some of the senile plaques visualized by Bielshowsky silver staining and some of reactive astrocytes were positively stained with the antisera against cathepsin D and cathepsin B in brains with Alzheimer's disease. Abnormal localization of cathepsin D and cathepsin B immunoreactivity in neuronal perikarya was observed in brains with early-onset Alzheimer's disease. These findings demonstrate that the distribution of lysosomal proteases was altered in brains with Alzheimer's disease, suggesting the primary and/or secondary involvement of the lysosomal proteases in the pathological process of Alzheimer's disease.  相似文献   
42.
目的探讨环氧化物酶-2(cyclooxygenase type 2,COX-2)及Ⅰ型前列腺素合成酶(membrane associated prostaglandin E-1,mPGES-1)在人颈动脉粥样硬化斑块中的表达变化及作用机制。方法收集24例人颈动脉粥样硬化斑块标本和10例肠系膜动脉标本做对照组,应用免疫组织化学及逆转录PCR方法测定COX-2及mPGES-1mRNA表达水平,Western印记方法检测COX-2及mPGES-1的蛋白表达水平。比较不同程度动脉粥样硬化组织间COX-2、mPGES-1 mRNA表达水平及蛋白表达水平。结果颈动脉粥样硬化斑块组的免疫组织化学染色检测COX-2和mPGES-1呈阳性表达,斑块组COX-2 mRNA和mPGES-1 mRNA表达与对照组相比上调,差异有统计学意义(P<0.05);COX-2及mPGES-1 mRNA上调水平相关(P<0.05);颈动脉粥样硬化斑块的COX-2蛋白表达上调水平与对照组相比差异有统计学意义(P<0.05);颈动脉粥样硬化斑块COX-2、mPGES-1 mRNA及蛋白表达水平与病理损害程度有关,差异有统计学意义(P<0.05)。结论COX-2及mPGES-1基因表达水平上调可能是进展性动脉粥样硬化损害的关键因素。  相似文献   
43.
An autoradiographic technique for the detection of antibody-forming cells has been developed for the assay of anti-DNP responses. The lymphoid cells suspension to be assayed was allowed to sediment on to a glass slide coated with DNP-conjugated gelatin to which the secreted antibody bound during subsequent incubation. The bound antibody and its Ig class was revealed by a second incubation using 125I-anti-immunoglobulin reagents followed by autoradiography. Studies on the sensitivity and specificity of the method are presented and its advantages over other techniques described. The technique should be readily applicable to other haptens.  相似文献   
44.
Summary Using a reverse hemolytic protein A plaque assay, spontaneous and pokeweed mitogen (PWM)-induced immunoglobulin (Ig) secretion was determined in peripheral blood from 22 patients with B1-chronic lymphocytic leukemia (CLL), one patient with B2-CLL, and one patient with suppressor T-CLL. Diagnoses were established by cytological and histological criteria as well as several marker analyses. Lymphocytes from B1- and B2-CLL patients were unable to secrete Ig either spontaneously or after PWM stimulation. In T-CLL lymphocytes, spontaneous Ig secretion was suppressed very probably by the OKT-8-positive leukemic population, since, after cultivation with PWM, a normal Ig secretion could be demonstrated which was paralleled by a decrease in the OKT-8-positive cells. Cocultivation experiments with freshly isolated, unseparated lymphocytes from normal subjects and lymphocytes from patients were of no informational value, since isolated normal B-cells alone already showed a high rate of Ig secretion. However, coculture experiments with separated subpopulations after PWM stimulation revealed an intrinsic B-cell defect in lymphocytes from B1-CLL patients, whereas their T-lymphocytes were found to be normal helper cells.
Abbreviations CLL Chronic lymphocytic leukemia - PWM Pokeweed mitogen - ISC Immunoglobulin-secreting cells - Ig Immunoglobulin(s) Supported by the Deutsche Forschungsgemeinschaft (Ru 215/2)  相似文献   
45.
Neutrophil accumulation in the lower respiratory tract of patients with fibrosing alveolitis is thought to be facilitated by IL-8, a neutrophil chemoattractant primarily secreted by mononuclear phagocytes. The aims of this study were: (i) to explore IL-8 secretion by lung and blood mononuclear phagocytes in subjects with cryptogenic fibrosing alveolitis, systemic sclerosis with and without fibrosing alveolitis, sarcoidosis and normal individuals; (ii) to examine IL-8 secretory heterogeneity in alveolar macrophages and peripheral blood monocytes; and (iii) to correlate alveolar macrophage phenotypic profile to IL-8 secretion. We observed that more monocytes secreted IL-8 than autologous macrophages and that there was heterogeneity in the in vitro IL-8 secretion by alveolar macrophages and peripheral blood monocytes. IL-8 secretion by alveolar macrophages was significantly higher in subjects with fibrosing alveolitis compared with subjects without fibrosing alveolitis, due to a higher percentage of IL-8-secreting alveolar macrophages in the fibrotic group both in the absence (P<0.002) and presence of lipopolysaccharide (LPS) (P<0.04) and correlated with bronchoalveolar lavage neutrophil percentage. Using the MoAbs RFD1, RFD7 and RFD9, that distinguish subsets of alveolar macrophages, we have been able to identify associations between secretion of IL-8 and smaller cells and the cells identified by the MoAb RFD7. In situ hybridization of the bronchoalveolar lavage cell population revealed that alveolar macrophages are the predominant source of IL-8 in the lung. We conclude that there is an increased number of IL-8-secreting alveolar macrophages in the lungs of patients with fibrosing alveolitis, and IL-8 secretion by these cells is associated with specific phenotypic profile expression.  相似文献   
46.
The use of the original haemolytic plaque reduction technique to measure cytotoxic T lymphocytes (CTL) has been developed further as a rapid screening assay, particularly suitable for limiting dilution analyses. Using hybridoma cells as targets, the cytotoxicity has been measured by the loss of haemolytic plaque formation and by the reduction of the amount of haemolytic monoclonal antibody secreted from viable target cells into the assay supernatants. The assessment of large numbers of cytotoxic samples has been greatly facilitated by quantitating the amount of haemoglobin released in the assay with an automated microELISA multiscanner and by scoring visually using a modification of the spot test. Using these new techniques, relatively high frequency estimates of cytotoxic cell precursors in an allogeneic response (1 in 462 spleen cells) and an anti-fluorescein response (1 in 3970 spleen cells) were obtained.  相似文献   
47.
The effects of heat labile, high molecular weight water-soluble toxins from bacterial plaque on HL60 promyelocytic cells were examined. On gel filtration, four inhibitors of HL60 cell growth and two inhibitors of HeLa cell growth (PT1, PT2) were detected. The first and third HL60 cell inhibitors corresponded to the two HeLa cell inhibitors. The last eluted HL60 cell inhibitor (plaque leukotoxin, PL) did not inhibit HeLa cell growth. Anti-PT2 antibodies reduced the activity of enriched PT2 by 20-50%, but all other antisera tested exhibited no effect. Anti-PL antibodies detected antigens from Actinobacillus actinomycetemcomitans, although anti-A. actinomycetemcomitans and anti-Capnocytophaga sputigena antibodies did not react with plaque extract. These findings suggest that the plaque toxins examined in this study were probably not derived from these two bacteria.  相似文献   
48.
This study considers false results which may arise due to problems in the preparation or examination of specimens for darkground microscopy of subgingival plaque. Subgingival plaque samples obtained with a sterile curette were placed in 0.1-0.3 ml sterile full or 1/4 strength Ringer's solution: 0.85% saline, 1% gelatin in 0.85% saline, formal saline or pyrogen-free water for injection. Test slides were prepared from the original dispersion, and control slides from the corresponding sterile solution. Optimal dispersion solution, syringe dispersion frequency and the effect on motility of delay in processing samples were tested. Slides were also prepared from dispersions of 11 representative subgingival "periodontopathic" organisms. Problems in sampling included variability in counts between sites with comparable pocket depths, contamination of the sample and reduction of the sample volume after scaling. Problems in dispersion included contamination, uneven distribution of the different morphotypes and destruction of delicate organisms. Problems in slide preparation included slide contamination, limitation in the number of samples that can be assessed by one examiner at a given time without loss of activity of motile cells, and preparation of a cell monolayer. Problems in identification and counting included confusion of Brownian movements with motility, coccoid particles with cocci, spirochetes with campylobacter, flagella with flagella-like structures, size of cocci, counting of fragmented spirochetes and non-motile flagellated organisms and motile cells, and also bias in counting. Problems in morphotype grouping included the observation that many (10 of the 11 representative) periodontitis-related organisms were in the non-motile groups and not all cells of the motile species (Campylobacter, Capnocytophaga) showed motility. The results indicate that each stage of subgingival plaque darkground microscopy, sampling, dispersion, slide preparation, counting, morphotype grouping and interpretation may lead to false results if not representative or reproducible. Procedures are suggested for the minimisation of problems in the preparation and examination of subgingival plaque specimens for darkground microscopy.  相似文献   
49.
摘 要: 目的:探究中老年人颈动脉斑块与血清25羟维生素D (25-OH-D) 的相关性。 方法:选取2019年1月—2020 年 12 月自愿参与该研究的上海市浦东新区北蔡社区常住居民 412 人为研究对象,测定及记录其一般临床资料及血清 25-OH-D 等实验室检测结果。依据血管 B 超结果将研究对象分为有斑块组 268 人和无斑块组 144 人,比较两组人群血清 25-OH-D水平差异,用Pearson相关性分析各变量的关系,采用logistic回归分析颈动脉斑块形成的危险因素。结果:有斑块 组血清 25-OH-D 为 (45.18±18.71) nmol/L,无斑块组为 (56.12±19.54) nmol/L,两组差异有统计学意义 (χ2=5.573,P< 0.05)。相关性分析显示颈动脉斑块与收缩压、HbA1c、年龄呈正相关 (r值分别为0.388、0.119和0.128,P值均<0.05);与 血清 25-OH-D 呈负相关 (r=-0.365,P<0.01)。血清 25-OH-D 是颈动脉斑块形成的独立相关因素 (OR=0.973,95%CI: 0.960,0.985,P<0.05)。结论:低水平血清25-OH-D是颈动脉斑块形成的独立危险因素。  相似文献   
50.
目的 研究颈动脉粥样斑与冠状动脉病变的关系。方法 将82例冠心病待排和冠心病患者按冠状动脉造影结果分成正常组和冠脉粥样病变组,同期超声检测颈动脉粥样硬化程度。结果 颈动脉粥样斑块与冠脉弱粥样硬化之间有较密切的关系。颈动脉粥样斑块对狭窄性冠状动脉病变预测的敏感性为71.7%,特异性为91.9%,阳性和阴性预测值分别为91.7%和73.9%,其准确性为81.7%。结论 颈动脉超声检测可作为预测冠状动脉粥样硬化有价值的指标。  相似文献   
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