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11.
蜂王浆冻干粉对小鼠肿瘤的抑制作用   总被引:4,自引:0,他引:4  
目的研究蜂王浆冻干粉对小鼠肿瘤的抑制作用.方法按每公斤体重0g、0.25g、0.50g、0.75g设对照及低、中、高3个剂量组,经口给予蜂王浆冻干粉30d后,接种小鼠肉瘤180(S180)和艾氏癌腹水型(EAC)两个瘤种.结果在两次重复的小鼠S180和EAC抑瘤试验中发现中剂量组瘤重明显低于阴性对照组(P<0.05),抑制率可达34%;中剂量组荷瘤小鼠平均生存时间均明显高于对照组(P<0.05).结论蜂王浆冻干粉具有抑制肿瘤的作用.  相似文献   
12.
Summary The present study provides information relevant to a number of variables which may influence response to treatment of nude mouse-grown human urothelial cancer. A number of xenotransplanted tumors were exposed to selected treatments at different transplant generations, and at various dose levels and treatment schedules. It was observed that nude mouse-grown tumors were characterized by consistency, reproducibility and biological stability not affected by the transplant generation at which they were examined. Treatment related dose response curves were steep, the sharpness of the curves depending on the degree of tumor sensitivity. Best therapeutic results were obtained at the maximum tolerated dose of cytotoxic agents under study and of importance, a 20% to 40% dose reduction with the same treatment schedule resulted in little or no activity. In addition, treatment schedule, timing and sequence of treatments and to a certain degree, tumor grade were important variables which could influence tumor response. The nude mouse-human tumor system provides important preclinical guidelines on dose, schedule, sequence and timing of treatments and can assist in designing more efficient clinical trials.  相似文献   
13.
赵琳蕾 《中华医学研究杂志》2007,7(5):406-408,I0002
目的观察中药“附归参汤”灌胃给药后是否可改善混合菌导致的小鼠输卵管炎性狭窄的病理改变。为临床应用“附归参汤”治疗输卵管炎所致的不孕症提供实验依据。方法昆明小鼠随机分为对照组(n=10)、模型组(n=10)、模型组+生理盐水处理组(n=10)、模型+“附归参汤”处理组(n=20),输卵管炎性狭窄模型采用混合菌(溶血性链球菌、大肠埃希菌和金黄色葡萄球菌2:1:1)输卵管接种法制作,处理组分别胃饲生理盐水和“附归参汤”30天。应用组织学方法观察各组的病理学改变,评判各处理组病理学转归情况。结果在使用混合菌接种后,小鼠输卵管管壁结构发生改变,主要包括黏膜层水肿、上皮细胞顶端纤毛变短或消失、固有层炎性细胞浸润、毛细血管充血、管腔狭窄甚至闭塞。“附归参汤”长期给药后明显使上述病理改变向正常组织转归。结论中药“附归参汤”能够修复混合菌导致的小鼠输卵管炎性狭窄的病理改变,为临床应用该药治疗输卵管炎所致的不孕症提供了实验依据。  相似文献   
14.
久泻宁动物毒性试验研究   总被引:1,自引:0,他引:1  
目的 (1)观察久泻宁一日内小鼠灌胃1~3次后的毒性反应和死亡情况,测定最大耐受量;(2)观察久泻宁给大鼠连续灌胃3个月,对机体产生的毒性反应、严重程度及可逆性,确定无毒剂量。为人拟用量提供参考。方法 (1)久泻宁小鼠灌胃,一日2~3次,观察急性毒性反应.测定最大耐受量;(2)久泻宁高、中、低三个剂量组和一个对照组,大鼠连续灌胃3个月,观察外观行为和体质量变化。试验期结束。每组取1/2动物活杀。检测血常规、血液生化、病理组织;1/2动物停药进行3周的恢复期观察后。同法检测上述指标。结果 久泻宁小鼠灌胃给药的最大耐受药量为750g/kg(含生药)。相当临床日拟用量(2.5g/kg)的300倍;大鼠连续3个月灌胃给药的无毒剂量为125g/kg(含生药).相当临床拟用量50倍。结论 久泻宁无明显毒性,安全范围大。临床日拟用量2.5g/kg、疗程1个月是安全的。  相似文献   
15.
Interleukin-18 is predominantly a macrophage-derived cytokine with a key role in inflammation and cell-mediated immunity. Having previously demonstrated IL-18 upregulation in a rat model of kidney rejection, here we examined IL-18 in a fully MHC-mismatched murine model of acute kidney rejection using IL-18-deficient recipients (IL-18-/-) and animals administered neutralizing IL-18 binding protein (IL-18BP). Gene expression of IL-18 and its receptor were significantly upregulated in allografts compared to isografts, as was the cellular infiltrate (T cells and macrophages) (p < 0.001). Allografts developed kidney dysfunction (p < 0.05) and tubulitis (p < 0.01) not observed in controls. There was a significant reduction in gene expression of IL-18 downstream pro-inflammatory molecules (iNOS, TNFalpha and IFNgamma) in IL-18-/- recipients (p < 0.01), and IL-18BP-treated animals. The CD4+ infiltrate and IL-4 mRNA expression was greater in the IL-18-/- recipients than wild-type (WT) allografts and IL-18BP-treated animals (p < 0.05), suggesting a Th2-bias which was supported by IFNgamma and IL-4 ELISPOT data and an increased eosinophil accumulation (p < 0.001). Neither IL-18 deficiency nor neutralization prevented renal dysfunction or tubulitis. This study demonstrates increased production of IL-18 in murine kidney allograft rejection and provides evidence that IL-18-induced pathways of inflammation are active. However, neither IL-18 deficiency nor neutralization was protective against the development of allograft rejection.  相似文献   
16.
克百威及其代谢产物的小鼠骨髓红细胞微核试验研究   总被引:1,自引:0,他引:1  
[目的]利用微核试验研究克百威及其4种代谢产物的遗传毒性。[方法]分别以0.1、0.2、0.4mg/kg3个不同剂量水平的克百威及其代谢产物3-羟基呋喃丹、3-酮基呋喃丹、呋喃酚和亚硝基呋喃丹腹腔注射染毒健康小鼠,24h后以同样剂量再次注射染毒,6h后脱颈椎处死动物,制片,观察并计数嗜多染红细胞的微核率,进行统计分析。[结果]克百威、呋喃酚及3-酮基呋喃丹小鼠胸骨骨髓嗜多染红细胞微核实验为阴性结果,高剂量处理组微核率分别为1.3‰、3.25‰和3.62‰,与阴性对照组(1.83‰)差异无显著性;而高剂量组3-羟基呋喃丹(7.00‰)和三个剂量组的亚硝基呋喃丹(微核率分别为3.62‰、5.00‰、7.85‰)均有明显微核效应。[结论]克百威、呋喃酚和3-酮基呋喃丹在受试剂量下微核试验阴性,3-羟基呋哺丹和亚硝基呋喃丹微核试验阳性,提示可能对染色体具有突变效应。  相似文献   
17.
用人喉癌手术切除标本建立了裸鼠移植瘤模型,已传至13代。原代移植成功率为66.7%,潜伏期30~70d;鼠间传代移植成功率为100%,潜伏期14~19d,生长稳定。经光学显微镜检查,各代移植瘤组织结构与原人喉癌组织基本一致。电镜检查证明,具有人喉癌特征,癌细胞间有大量桥粒,细胞浆中可见张力原纤维,有的张力原纤维与桥粒相连。细胞表面有较大的指状突,核膜较规则,胞浆中线粒体较多。  相似文献   
18.
Background The role of IgE in airway hyperreaetivity is obscure. Objective In order to clarify the role of IgE in airway hyperreactivity, we investigated the effect of anti-IL-4 monoclonal antibody, rapamycin and interferon-γ on the antigen-induced IgE response, airway eosinophilia and hyperreactivity in mice. Methods Mice were immunized with an antigen (ovalbumin; OA) at intervals of 12 days. OA was inhaled 10 days after the secondary immunization. Twenty-four hours after the last inhalation, airway reactivity to acetylcholine was measured and bronchoalveolar lavage fluid (BALF) was obtained. Results Three inhalations of antigen caused an increase in the number of eosinophils in bronchoalveolar lavage fluid (BALF) and in airway hyperreactivity to acetylcholine with a significant elevation of serum IgE level. Anti-IL-4 at a dose of 1000 μg/animal and rapamycin at doses between 0.1 and 1 mg/kg inhibited the IgE production, but did not affect the airway eosinophilia or hyperreactivity to acetylcholine. In contrast, IFN-γ clearly inhibited the antigen-induced airway eosinophilia and hyperreactivity, but did not affect the IgE antibody production. Conclusion These results suggest that the inhibition of IgE production does not suppress the onset of airway hyperreactivity and eosinophilia in mice, and that IFN-γ inhibits the antigen-induced airway hyperreactivity, probably due to the inhibition of airway eosinophilia.  相似文献   
19.
ThedynamicdistributionofnitricoxidesynthaseinthesmallintestineofmicewithintestinalradiationsicknessWeiLichun(魏丽春);GuoYao(郭鹞)(...  相似文献   
20.
Central nervous system (CNS) progenitor cells transiently proliferate in the embryonic neural tube and give rise to neurons and glial cells. A characteristic feature of the CNS progenitor cells is expression of the intermediate filament nestin and it was previously shown that the rat nestin second intron functions as an enhancer, directing gene expression to CNS progenitor cells. In this report we characterize the nestin enhancer in further detail. Cloning and sequence analysis of the rat and human nestin second introns revealed local domains of high sequence similarity in the 3' portion of the introns. Transgenic mice were generated with the most conserved 714 bp in the 3' portion of the intron, or with the complete, 1852 bp, human second intron, coupled to the reporter gene lacZ. The two constructs gave a very similar nestin-like expression pattern, indicating that the important control elements reside in the 714 bp element. Expression was observed starting in embryonic day (E)7.5 neural plate, and at E10.5 CNS progenitor cells throughout the neural tube expressed lacZ. At E12.5, lacZ expression was more restricted and confined to proliferating regions in the neural tube. An interesting difference, compared to the rat nestin second intron, was that the human intron at E10.5 mediated lacZ expression also in early migrating neural crest cells, which is a site of endogenous nestin expression. In conclusion, these data show that a relatively short, evolutionarily conserved region is sufficient to control gene expression in CNS progenitor cells, but that the same region differs between rodents and primates in its capacity to control expression in neural crest cells.  相似文献   
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