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Oral ulcerations associated with HIV infection include recurrent aphthous ulcers (RAU). Whereas RAU prevalence is not increased, lesion severity is: among a group of HIV+ patients, 66% had the more severe herpetiform or major RAU. This increased severity suggests that HIV disease-related changes in the immune system may exacerbate RAU. In the peripheral blood of healthy subjects with RAU, CD4:CD8 cell ratios may be reversed and the proportion of T cell receptor-γδ+ cells increased. HIV disease-related immune system changes are characterized by reversed CD4:CD8, lowered CD4 cell counts and an inverse correlation between CD4 cell counts and per cent activated γδ lymphocytes. Adhesion molecules and cytokines involved in lymphocyte homing may be important in RAU pathogenesis: ICAM-I and ELAM are strongly expressed, and TNFα production is increased in peripheral blood lymphocytes of healthy patients with RAU. In patients with active HIV disease/AIDS, serum TNFα levels are increased. Thalidomide, which inhibits TNFα production, is effective treatment for RAU. Some RAU patients have vitamin B12 or folate deficiencies, levels of which are commonly low in HIV+/AIDS patients. However, in a case control study of HIV+ patients, vitamin B12- or folate-deficiencies were not found to be significant risk factors for RAU.  相似文献   
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Hairy leukoplakia (HL) is a lesion found on the side of the tongue of immunocompromised individuals, including those with human immunodeficiency virus (HIV) infection. The lesion has unique histopathologic features and is characterised by high-level Epstein-Barr virus (EBV) replication, multiple EBV strains, and extensive inter-and intra-strain recombination. Expression of EBV genes spanning the entire viral life cycle from latency-associated genes to late, replicative genes has been detected in the lesion. HL thus provides a unique opportunity to study EBV expression in oral epithelium, and to study expression of novel EBV genes. We therefore constructed a cDNA library from an HL biopsy and detected expression of two genes not previously described in vivo: BMRF-2 and BDLF-3. Sequence analysis of the cDNAs revealed few amino acid changes from the B95-8 sequence. Expression of both genes was localized to the lower prickle cell layer of the tongue epithelium. BMRF-2 protein expression was primarily detected in the cell nuclei of the upper prickle cell layer. BDLF-3 protein expression was observed in the perinuclear space and Golgi compartment. The function of these proteins is currently under investigation.  相似文献   
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二氧化碳气腹对肿瘤细胞生长和播散影响的研究   总被引:4,自引:0,他引:4  
目的 研究静脉使用 5 %NaHCO3 纠正CO2 气腹造成的酸中毒能否改善其对肿瘤细胞的促生长和播散作用。方法 观察静脉推注 5 %NaHCO3 的CO2 气腹组、CO2 气腹组及对照组带瘤Wister大鼠的肿瘤生长及穿刺点转移情况。结果 静脉推注 5 %NaHCO3 的CO2 气腹组、CO2 气腹组及对照组肿瘤的重量、体积和腹水体积有差异 ,但无统计学意义。穿刺点转移率无明显差异。结论 CO2 气腹影响肿瘤细胞生长和播散的机制复杂 ,不能完全以CO2 引起机体酸中毒解释。未找到通过静脉推注 5 %NaHCO3 可改善CO2 气腹对肿瘤细胞生长影响的基础理论依据。  相似文献   
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喇慧  权丽丽  张玉琼 《癌症进展》2021,19(18):1871-1873,1881
目的 探讨血清高迁移率族蛋白A2(HMGA2)、糖类抗原125(CA125)、人附睾蛋白4(HE4)对卵巢上皮癌的诊断价值.方法 将50例卵巢上皮癌患者作为恶性组,30例良性卵巢肿瘤患者作为良性组,30例良性妇科疾病患者作为对照组,比较3组患者血清HMGA2、CA125、HE4水平及不同病理类型卵巢上皮癌患者HMGA2、CA125、HE4水平,采用受试者工作特征(ROC)曲线分析HMGA2、CA125、HE4诊断卵巢上皮癌的临床价值.结果 恶性组患者血清HMGA2、CA125、HE4水平均高于良性组和对照组,差异均有统计学意义(P﹤0.05).浆液性癌及黏液性癌患者血清CA125、HE4水平均高于子宫内膜样癌患者,且浆液性癌患者血清CA125水平高于黏液性癌患者,差异均有统计学意义(P﹤0.05).HMGA2、CA125、HE4联合诊断卵巢上皮癌的曲线下面积(AUC)为0.995,大于三者单独诊断的AUC(0.925、0.944、0.936).结论 HMGA2联合CA125、HE4诊断卵巢上皮癌能够显著提高临床诊断价值,能够作为卵巢癌的重要辅助诊断指标.  相似文献   
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目的:建立UPLC-MS-MS同时测定大鼠血浆中2,3,5,4'-四羟基二苯乙烯-2-O-β-D-葡萄糖苷,1-脱氧野尻霉素和决明子苷、红镰霉素龙胆二糖苷、橙黄决明素、甲基钝叶决明素、白藜芦醇的分析方法,研究大鼠服用滋肾清肝代平方后的药代动力学特征。方法:采用Waters Acquity UPLC BEH C18色谱柱,流动相0.1%甲酸水溶液-乙腈梯度洗脱,采用电喷雾电离源,扫描方式为多反应离子监测。结果:7种成分在大鼠血浆中线性关系良好,提取回收率94.83%~106.58%,日内、日间精密度和准确度良好。7种成分在模型组大鼠中的药时曲线下面积、末端半衰期、达峰时间、清除率、表观分布容积、药峰浓度分别为(326.65±26.66)μg·L-1·h-1,(3.64±1.69)h,0.33 h,(60.56±5.32)L·h-1·kg-1,(325.13±167.18)L·kg-1,(169.25±18.02)μg·L-1。结论:该方法特异、快速、准确、灵敏,可用于滋肾清肝代平方在大鼠体内的药动学研究。  相似文献   
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Positron emission tomography (PET) with the high affinity dopamine D2/3 receptor ligand [18F]‐fallypride affords estimates of the binding potential (BPND) in extra‐striatal regions of low receptor abundance, but the sufficient recording time for accurate measurements in striatum has been called into question. We have earlier argued that transient equilibrium measurements are obtained in striatum with [18F]‐fallypride PET recordings of 3 h duration, which may be the practical limit for clinical investigations without interrupted scanning. However, the high extraction fraction of [18F]‐fallypride predicts flow‐dependence of tracer delivery to brain, which may be a source of variance of the apparent BPND in regions of high binding. To test this prediction, we conducted a retrospective analysis of [18F]‐fallypride PET data from a group of 50 healthy volunteers (age 18–58 years [mean ± SD: 32.6 ± 10.6), who had participated in clinical studies without arterial input measurements. We used the initial 120‐s integral (AUC) of the venous confluence (VC) as a surrogate marker for cerebral blood flow (CBF) and tested for correlations between regional estimates of BPND calculated by the simplified reference tissue model (SRTM) and the individual VC‐AUC. The magnitude of BPND in a high binding region (putamen), but not in a low binding region (thalamus) correlated positively with VC‐AUC, suggesting that approximately 9% of the variance in the [18F]‐fallypride BPND in putamen can be attributed to individual differences in this surrogate marker for CBF, a contribution equal in magnitude to the effects of age on BPND in putamen of the present healthy control group. Synapse, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
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The human airways are protected from invading micro-organisms by the highly efficient innate immune system. Antimicrobial peptides that are produced by inflammatory cells and airway epithelial cells are key elements in this innate immune system. A major subgroup of the antimicrobial peptides is the family of defensins - small non-enzymatic and cationic peptides. Besides their extensively studied role in antimicrobial defense, recent studies have demonstrated that defensins are also able to modulate inflammatory responses, to stimulate adaptive immunity and contribute to tissue repair. In line with these observations, increased defensin levels were observed in inflammatory lung diseases, such as cystic fibrosis (CF), diffuse panbroncheolitis (DPB), idiopathic pulmonary fibrosis (IPF) and acute respiratory distress syndrome (ARDS), and in infectious diseases. In the past decade much has been learnt about the activity of defensins and there is abundant evidence for their presence in human inflammatory lung disease. Future studies are required to elucidate their role in the pathogenesis of these diseases.  相似文献   
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