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991.
目的 研究我国东北地区未接受抗逆转录病毒治疗的HIV AIDS患者HIV毒株的逆转录酶和蛋白酶耐药变异情况 ,为开展大规模临床抗病毒药物治疗提供本底数据。方法 RT PCR和套式PCR扩增HIVpol区基因 ,双脱氧法测定逆转录酶和蛋白酶基因序列 ,与国际耐药数据库比对辨别耐药变异。结果  (1) 5 3例患者毒株亚型分析结果 :B′亚型 4 7例 ,B′ C亚型 4例 ,A、B亚型各 1例 ;(2 )未发现逆转录酶和蛋白酶原发耐药变异存在 ,但发现存在逆转录酶抑制剂继发变异 :M4 1L(1.9% )、I6 3M (1.9% )、L74I (1.9% )、S6 8G (1.9% )、V75L (3.8% )、V10 6I (1.9% )、I135L T (5 .7% )、V179D (7.5 % )和V189I (1.9% ) ,无症状感染者RT继发耐药变异出现率为 11.8% ,而艾滋病患者为5 2 .6 % (P <0 .0 1)。存在大量蛋白酶耐药继发变异V77I (88.7% )、L6 3P (86 .8% )、E35D (81% )、A71V(2 4 .5 % )、R4 1K (15 .1% )、L10I (9.4 % )、R5 7K (9.4 % )、D6 0E (9.4 % )、N37D (5 .7% )、G16E (3.8% )、I15V (1.9% )、M36I (1.9% )、K5 5R (1.9% )和L89M (1.9% )。未发现明显的亚型特异性耐药变异。结论 在中国东北地区未接受抗逆转录病毒治疗的HIV AIDS患者中未发现毒株逆转录酶和蛋白酶耐药原发变异 ,但大量继发耐药变异的存在提  相似文献   
992.
目的 探讨经淋巴道转移的小鼠肝癌细胞高低转移株HCa F、HCa P淋巴道转移能力及与淋巴细胞归巢受体L 选择蛋白的相关性。方法 应用免疫印迹分析、RT PCR及流式细胞术检测小鼠肝癌HCa F、HCa P细胞表面L 选择蛋白的表达情况 ,再通过E 、P 、L 选择蛋白的抗体对细胞粘附实验的影响检测HCa F、HCa P细胞淋巴道转移潜能与L 选择蛋白的相关性。结果 L 选择蛋白在HCa F、HCa P细胞表面均有表达 ,且HCa F细胞的表达量明显高于HCa P细胞 (P <0 .0 1) ,HCa F细胞与淋巴结之间的粘附可被抗L 选择蛋白的抗体所阻断。结论 小鼠肝癌细胞高低转移株HCa F、HCa P细胞均表达L 选择蛋白 ,其程度与该细胞的淋巴道转移潜能正相关  相似文献   
993.
Monocyte chemoattractant protein-1 (MCP-1) is a pivotal mediator of angiocentric granuloma formation in glucan-induced pulmonary granulomatous vasculitis. Based on the rationale that mononuclear phagocytes retrieved from granulomas are rich sources of nitric oxide (NO) and that the recruitment of mononuclear phagocytes into lesions abates as granuloma formation slows, we tested the hypothesis that MCP-1 gene expression is regulated by a NO-sensitive mechanism. Preexposure of endothelial cell (EC) monolayers to NO donor compounds markedly reduced cytokine-induced MCP-1 expression and cytosolic-to-nuclear translocation of nuclear factor-kappa B (NF-B), reversed fluctuations in endothelial reduced glutathione (GSH) pools but did not affect cGMP concentrations. The lungs of mice bearing targeted disruptions of the inducible nitric oxide synthase (iNOS) gene exhibited significantly higher concentrations of MCP-1 following glucan infusion than did those of wild-type mice. Cumulatively, these data suggest that NO suppresses MCP-1 expression by blunting the redox changes associated with cytokine-induced EC activation.  相似文献   
994.
牛IL-18基因的克隆及遗传进化分析   总被引:3,自引:0,他引:3  
目的:克隆牛白细胞介素18(IL-18)全基因,并对其进行序列分析。方法:从ConA刺激培养的牛外周血淋巴细胞提取总RNA,利用巢式RT-PCR方法扩增出牛IL-18全长cDNA,将其克隆到pMDl8-T载体上,测序后进行序列分析。结果:成功地克隆到了牛IL-18全基因,序列分析表明,实验中所克隆到的牛IL-18序列与GeneBank所登录的牛IL-18核苷酸序列及其推导氨酸序列同源性分别是99.5%和99%。与人、猕猴、野猪、山羊属、马等核苷酸序列及其推导氨基酸序列同源性分别在84.9%-99.5%和74.9%~99%之间,研究结果在国内还未见报道。结论:成功地从牛外周血中克隆到了牛IL-18的基因,其全长为598bp。  相似文献   
995.
细胞外信号调节蛋白激酶(ERK)1/2是重要的信号转导分子。现已知在正常动物的中枢神经系统内有其活化形式即磷酸化的ERK1/2(pERK1/2)分子的存在,但其在小鼠脑内的分布目前还没有全面的观察。本研究用免疫组织化学技术(ABC法)研究了pERK1/2样免疫反应阳性产物在脱臼处死的正常小鼠全脑内的分布。结果发现pERK1/2在正常小鼠脑内有广泛的表达,阳性产物主要存在于神经元,亦见于个别白质内的胶质细胞,脑膜及室管膜细胞也有表达。强阳性表达的核团主要有:岛皮质、视听皮质、边缘前皮质、扣带前皮质、海马垂直部、弓状核、蓝斑和小脑Purkinje细胞;中等阳性表达的核团主要有:感觉运动皮质、外侧隔区、内侧杏仁核、皮质杏仁核和外侧杏仁核、丘脑室旁核前部、视交叉上核、穹隆下器、终板血管器、前腹侧视前核和下丘脑背内侧核;弱阳性表达的核团主要有:视上核、下丘脑室旁核大细胞部、下丘脑后区、顶盖前区、室周灰质腹外侧柱、A5区、孤束核和延髓腹外侧网状结构等。本文结果观察到pERK1/2在正常小鼠脑内广泛存在,提示pERK1/2作为重要的信号转导分子,可能参与许多脑区在正常状态下的功能活动,揭示其分布特点为了解其在脑内的多样性功能提供了形态学依据。  相似文献   
996.
The classification of urothelial neoplasms of the kidney traditionally has been similar to that of urinary bladder tumors. Several years ago, the classification of papillary urothelial neoplasms was revised. The current study focuses on the application of the 1998 World Health Organization (WHO)/International Society of Urological Pathology classification system to 102 renal pelvic urothelial neoplasms and compares it to the 1973 WHO classification scheme. In this study, all tumors were classified as urothelial carcinomas, and the majority (85%) were papillary. Most patients with papillary tumors presented with 'superficial' disease (< or = pT1). With the 1998 system, most papillary carcinomas were high grade, and were more often invasive as compared to low-grade tumors. Only 34% were low-grade papillary tumors and, of these, most (93%) were noninvasive. With the 1973 system, most papillary tumors were grade 2 or 3, with invasion more common in grade 3 tumors. By 1973 criteria, grade 2 tumors were a heterogeneous group; with 1998 criteria, nearly one-half were high grade and the other half low grade. The grade of papillary urothelial carcinomas with both the 1973 and 1998 grading methods was associated with stage (P=0.001). Our study reveals that papillomas and papillary urothelial neoplasms of low malignant potential are uncommon tumors in the kidney. Renal pelvic papillary urothelial neoplasms are most often carcinomas and are more commonly high grade than low grade. Although both the 1973 and 1998 systems showed a significant association with tumor stage, grade 2 papillary carcinomas are a heterogeneous group by 1973 criteria. The 1998 system provides useful information in that it more clearly defines a papillary tumor's grade and selects for a group of tumors, namely low-grade papillary urothelial carcinomas, for which a low likelihood of invasion can be predicted.  相似文献   
997.
BACKGROUND: Many patients with asthma have an IgE-mediated allergic component to the disease. Omalizumab, a monoclonal anti-IgE antibody, has demonstrated clinical efficacy in patients with allergic asthma. The effects of omalizumab on inflammation in asthma are not completely understood. OBJECTIVES: To evaluate the effects of omalizumab on allergen- and growth factor-stimulated proinflammatory cytokine and nitric oxide (NO) production in human bronchial epithelial cells (BECs) and to compare them to the effects of budesonide, a corticosteroid with known anti-inflammatory properties. METHODS: Human BECs were stimulated in duplicate with interleukin 1beta (IL-1beta), 100 U/mL; ragweed, 10 microg/mL; dust mite, 1000 AU; and epithelial growth factor, 40 ng/mL; and either 10(-7) M budesonide or 0.1 microg/mL of omalizumab in a 4% dust mite atopic serum medium for 6 and 24 hours in 5% carbon dioxide at 37 degrees C. Tumor necrosis factor alpha and transforming growth factor betaexpression and production and IL-4, IL-13, and NO production were assayed using gene-specific messenger RNA or sensitive enzyme-linked immunosorbent assays. RESULTS: Omalizumab inhibited the expression and of production proinflammatory cytokines and growth factor in antigen-stimulated BECs at 6 and 24 hours. Production of NO was inhibited at 6 hours and increased at 24 hours by omalizumab and budesonide. CONCLUSIONS: The effects of omalizumab were similar to those of budesonide. These results, consistent with previously reported evidence of anti-inflammatory effects of omalizumab, demonstrate that omalizumab may reduce airway inflammation and probably contributes to decreased airway remodeling in patients with asthma.  相似文献   
998.
BACKGROUND: Increased total serum IgE levels are a common characteristic of atopic disorders. Six potentially functional variants, including C-590T in the IL4 gene, C-1055T and Arg130Gln in the IL13 gene, and Ile50Val, Ser478Pro, and Gln551Arg in the IL4RA gene, have been evaluated for their involvement in the control of total serum IgE levels and related atopic disorders, but the results of these studies have been inconsistent. OBJECTIVE: We examined whether these 6 variants had genotypic effects on total serum IgE levels in 823 unrelated German children from a large infant cohort, the German Multicenter Atopy Study. METHODS: Marginal effect models were used for the analyses of the repeated IgE measurements. Weighted linear regression and family-based tests of association were performed to minimize the possibility of spurious effects caused by selection bias or confounding on the basis of ethnic background. RESULTS: There are significant associations between increased total serum IgE levels and 2 variants in the IL13 gene (P <.005 and.0002 for Arg130Gln and C-1055T, respectively). These genetic effects are unlikely to be due to solely linkage disequilibrium between 2 polymorphisms, population stratification, or nonrepresentative samples. In addition, exposure to maternal smoking appears to modify the above effects on total serum IgE levels. However, no statistical association was observed between this quantitative phenotype and the other 4 variants examined. CONCLUSION: These findings suggest that variants C-1055T and Arg130Gln of the IL13 gene might play an important role on total serum IgE production in this study population.  相似文献   
999.
Pleomorphic xanthoastrocytoma (PXA) is a rare, low-grade astrocytic tumor found in the central nervous system. Histologically, the tumor is characterized by markedly pleomorphic and lipidized cells. Although most of the patients have a favorable prognosis, a small number of cases undergoing recurrence or progression to anaplastic astrocytoma were reported. Very few genetic studies have been performed on PXA because of its rarity and the pathogenesis of this neoplasm is largely unknown. In order to provide an overview of genetic alterations in PXA, we performed comparative genomic hybridization to identify chromosomal imbalances (DNA gains and losses) in three cases of PXA. Genetic imbalance was detected on at least one chromosome for each case. One case, which revealed multiple genetic alterations, showed a poor prognosis. DNA gain on chromosome 7 and loss on 8p were demonstrated in two of three cases, suggesting that the candidate gene(s) located on these regions may play a role in the development of PXA. Further studies are needed to identify the residing candidate genes that are involved in the tumorigenesis of PXA. In addition, the histopathological features and previous genetic studies on PXA are reviewed.  相似文献   
1000.
Previous estimates of the prevalence of fatigue and chronic fatigue have derived largely from treated populations and have been biased by differential access to health-care treatment linked with gender, racial/ethnic and social class status. This study involves a community-based prevalence study of prolonged fatigue and chronic fatigue. It addresses: (1) the rate of prolonged fatigue and chronic fatigue in a socioeconomically and ethnically diverse sample of 28,673 adults in Chicago; and (2) establishes the relative prevalence of prolonged fatigue and chronic fatigue across race/ethnicity, socio-economic status and gender. Univariate and multivariate statistical techniques were utilized to delineate the overall rate of prolonged fatigue and chronic fatigue in the Chicago population and its relative prevalence by gender, race/ethnicity, and social class. Findings indicated that fatigue is common in urban populations, but that prolonged fatigue and chronic fatigue occur in about 5.00 to 7.68 percent and 2.72 to 4.17 percent, respectively, of the sample of the population. Highest levels of fatigue were consistently found among women and those with lower levels of education and occupational status.  相似文献   
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