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41.
原料药中基因毒性杂质控制的研究进展   总被引:5,自引:5,他引:0  
目的介绍原料药(active pharmaceutical ingredient,API)中基因毒性杂质控制的法规要求、评估方法和控制方法。方法通过学习欧美法规发展历史,理解国际高端市场对基因毒性杂质控制的监管期望,提出原料药中基因毒性杂质风险评估方法。结果与结论企业基于半定量评估,结合清除研究数据,建立科学的控制策略,使实际工艺中所有可能涉及的基因毒性杂质风险得到明确鉴别和控制,是达到监管期望的有效途径。  相似文献   
42.

Aim:

Protopanaxtriol (Ppt) is extracted from Panax ginseng Mayer. In the present study, we investigated whether Ppt could protect against 3-nitropropionic acid (3-NP)-induced oxidative stress in a rat model of Huntington''s disease (HD) and explored the mechanisms of action.

Methods:

Male SD rats were treated with 3-NP (20 mg/kg on d 1, and 15 mg/kg on d 2–5, ip). The rats received Ppt (5, 10, and 20 mg/kg, po) daily prior to 3-NP administration. Nimodipine (12 mg/kg, po) or N-acetyl cysteine (NAC, 100 mg/kg, po) was used as positive control drugs. The body weight and behavior were monitored within 5 d. Then the animals were sacrificed, neuronal damage in striatum was estimated using Nissl staining. Hsp70 expression was detected with immunohistochemistry. Reactive oxygen species (ROS) generation was measured using dihydroethidium (DHE) staining. The levels of components in the Nrf2 pathway were measured with immunohistochemistry and Western blotting.

Results:

3-NP resulted in a marked reduction in the body weight and locomotion activity accompanied by progressive striatal dysfunction. In striatum, 3-NP caused ROS generation mainly in neurons rather than in astrocytes and induced Hsp70 expression. Administration of Ppt significantly alleviated 3-NP-induced changes of body weight and behavior, decreased ROS production and restored antioxidant enzymes activities in striatum. Moreover, Ppt directly scavenged free radicals, increased Nrf2 entering nucleus, and the expression of its downstream products heme oxygenase-1 (HO-1) and NAD(P)H quinone oxidase 1 (NQO1) in striatum. Similar effects were obtained with the positive control drugs nimodipine or NAC.

Conclusion:

Ppt exerts a protective action against 3-NP-induced oxidative stress in the rat model of HD, which is associated with its anti-oxidant activity.  相似文献   
43.
44.
大黄酸对糖尿病大鼠转化生长因子β及其受体表达的影响   总被引:7,自引:0,他引:7  
目的:探讨大黄酸对STZ糖尿病大鼠肾组织转化生长因子β(TGF-β)及其Ⅰ型(TβRⅠ)、Ⅱ型受体(TβRⅡ)的影响及其可能作用机制。方法:采用STZ腹腔注射法建立糖尿病动物模型。96只3月龄雌性Wistar大鼠随机分为正常对照组,糖尿病模型对照组,低剂量大黄酸治疗组[35mg/(kg·d)]和高剂量大黄酸治疗组[70mg/(kg·d)]。第4、8、12周各组处死8只大鼠并收集标本,记录体重、左肾重,检测血糖、血肌酐、24h尿蛋白排泄量,ELISA法检测24h尿TGF-β水平。RT-PCR法、Westernblot法及免疫组化法检测肾组织TGF-β、TβRⅠ、TβRⅡ、FN及葡萄糖转运蛋白1(GLUT1)mRNA及蛋白质表达水平。结果:糖尿病模型大鼠血糖及24h尿蛋白排泄量明显增高,肾组织TGF-β、TβRⅠ、TβRⅡ及FNmRNA表达水平在12周内表现进行性升高,肾组织GLUT1mRNA水平在12周内表现为先下调,再上调的趋势。而肾组织TGF-β、TβRⅠ、TβRⅡ、FN及GLUT1蛋白质表达水平均在8周时达到高峰值,12周时表现下降。大黄酸治疗可时间-剂量依赖性降低糖尿病大鼠血糖水平,减少24h尿蛋白排泄量,血肌酐水平下降,使肾重指数下降。大黄酸治疗可时间-剂量依赖性下调糖尿病大鼠肾组织TGF-β、TβRⅠ、TβRⅡ、FN及GLUT1mRNA及蛋白质的表达水平。结论:大黄酸可通过降低糖尿病大鼠血糖水平,一方面直接减少TGF-β的合成,另一方面通过抑制己糖胺通路异常活化,抑制GLUT1的产生及其功能活性,减少TGF-β的产生,从而下调TβRⅠ、TβRⅡ表达,降低肾内TGF-β系统活性,延缓糖尿病肾病的发展。  相似文献   
45.
BACKGROUND: The influence of interleukin-10 (IL-10) gene promoter polymorphisms on the mode and sequel of HBeAg seroconversion (a favorable event usually) in patients with chronic Hepatitis B virus (HBV) infection has not been clarified. PATIENTS AND METHODS: IL-10 genotyping and haplotype analyses of 340 HBsAg carriers and 100 volunteers with self-limiting HBV infection from southern China, a high prevalent area of HBV were performed according to the single nucleotide polymorphisms in its promoter (-1,082, -819 and -592) using a competitively differentiated PCR. RESULTS: High-producer genotype (GG at -1,082) or haplotype (GCC) was rarely found in patients from southern China (<1%). Intermediate-producer haplotype (ACC) was closely associated with chronic liver disease (P=0.004); compared with this, low-producer genotype (AA at -592) and haplotype (ATA) were closely associated with asymptomatic carriers (P=0.035 and 0.035). Intermediate-producer genotype (AC at -592) and haplotype (ACC) were closely associated with covert seroconversion of HBeAg (P=0.0086 and 0.0013) and progressive sequel after HBeAg seroconversion (P=0.013 and 0.0008), while, low-producer genotype (AA at -592) and haplotype (ATA) were closely associated with overt seroconversion of HBeAg (P=0.0023 and 0.0061) and silent sequel after HBeAg seroconversion (P=0.0009 and 0.001). CONCLUSIONS: IL-10 gene promoter polymorphisms significantly influence the mode and sequel of HBeAg seroconversion in patients with chronic HBV infection.  相似文献   
46.
皮质激素辅助治疗结核性脑膜炎的研究现状   总被引:2,自引:0,他引:2  
结核性脑膜炎(tuberculous meningitis,TBM)以血脑屏障紊乱、颅内压升高和脑水肿为特征,是人型结核分枝杆菌感染最严重的类型。未经治疗死亡率达100%,治疗后死亡率约为10%,生存者中约80%有严重的神经系统后遗症。随着新增病例的不断增多,世界卫生组织(World Health Organiza-tion,WHO)在2007年的结核防治报告中提出:“要让所有结核患者都有机会得到有效的治疗。”目前尚没有明确针对TBM最佳治疗方案的临床指南。临床上主要参考肺结核的治疗方案。  相似文献   
47.
白介素-10基因多态性与狼疮性肾炎的关系   总被引:2,自引:0,他引:2  
目的 :探讨白介素 10 (IL 10 )基因多态性与狼疮性肾炎 (LN)的发病和临床病理损害的联系及其在LN分子诊断中的意义。  方法 :提取 10 0例健康志愿者及 2 4 6例LN患者全血DNA ,限制性片断长度多态性法检测IL 10基因 5 92位点A/C单核苷酸多态性在正常人群和LN患者总体及不同病理亚型组的分布 ,比较不同基因型组的临床表现、病理损害的差异 ,并研究其对血清IL 10水平的影响。  结果 :IL 10基因 5 92A/C多态性在正常人群和LN患者的分布无显著差别 ,IL 10高表达基因型AC&CC患者的疾病活动性指数、尿蛋白、尿沉渣红细胞和肾小球袢内血栓的发生率均显著高于IL 10低表达基因型AA患者 ;结合肾活检病理分型进行分析发现 ,IL 10高表达相关的基因型 (AC&CC)在Ⅳ型LN患者的分布显著高于Ⅱ型和Ⅴa型患者。LN患者各基因型组血清IL 10水平无统计学差异 ,但AA型 相似文献   
48.
Zhao  Jia-min  Ji  Ling-ling  Han  Meng-qi  Mou  Qing-nan  Chu  Guang  Chen  Teng  Du  Shao-yi  Hou  Yu-xia  Guo  Yu-cheng 《International journal of legal medicine》2021,135(5):1887-1901
International Journal of Legal Medicine - Lips are the main part of the lower facial soft tissue and are vital to forensic facial approximation (FFA). Facial soft tissue thickness (FSTT) and linear...  相似文献   
49.
To explore the relationship between social support and sleep quality of community workers in Wuhan during the coronavirus disease 2019 (the COVID-19 infection epidemic), this research constructed a mediating effect model to explore the mediating psychological mechanism of social support influencing sleep quality of front-line community workers. A total of 500 front-line community workers in Wuhan were investigated. We used the perceived social support scale (PSSS), the Connor-Davidson Resilience Scale (CD-RISC), the perceived stress scale (PSS), and the Pittsburgh sleep quality index (PSQI) to measure social support, psychological resilience, perceived stress and sleep quality. Specifically, the higher the PSQI, the worse the sleep quality. Pearson correlation structural equation model was used to analyze the relationship between these factors. The results showed that: (1) There was a significant negative correlation between social support, psychological resilience, and perceived stress of community workers and PSQI, that means, the higher the level of social support, psychological resilience, and perceived stress, the higher the sleep quality. (2) Social support positively predicted psychological resilience and perceived stress, and perceived stress negatively predicted PSQI. (3) Social support can affect sleep quality through the mediating role of psychological resilience and perceived stress, and the mediating role includes two paths: the single mediating role of perceived stress and the chain mediating role of psychological resilience-perceived stress. (4) Gender moderates the relationship between social support and perceived stress, and the influence of social support on perceived stress of women is higher than that of men. Gender moderates the relationship between psychological resilience and PSQI, and only women’s psychological resilience had a negatively predictive effect on PSQI, while men did not, which means that psychological resilience of female frontline community workers can positively predict sleep quality. This research reveals the relationship between social support and sleep quality and its mechanism and verifies that social support can indirectly affect physical health through psychological resilience and perceived stress. It provides reference suggestions and intervention guidance for improving the sleep quality of community workers.  相似文献   
50.
To investigate the factors associated with the duration of severe acute respiratory syndrome coronavirus 2 RNA shedding in patients with coronavirus disease 2019 (COVID‐19). A retrospective cohort of COVID‐19 patients admitted to a designated hospital in Beijing was analyzed to study the factors affecting the duration of viral shedding. The median duration of viral shedding was 11 days (IQR, 8‐14.3 days) as measured from illness onset. Univariate regression analysis showed that disease severity, corticosteroid therapy, fever (temperature>38.5°C), and time from onset to hospitalization were associated with prolonged duration of viral shedding (P < .05). Multivariate regression analysis showed that fever (temperature>38.5°C) (OR, 5.1, 95%CI: 1.5‐18.1), corticosteroid therapy (OR, 6.3, 95%CI: 1.5‐27.8), and time from onset to hospitalization (OR, 1.8, 95%CI: 1.19‐2.7) were associated with increased odds of prolonged duration of viral shedding. Corticosteroid treatment, fever (temperature>38.5°C), and longer time from onset to hospitalization were associated with prolonged viral shedding in COVID‐19 patients.  相似文献   
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