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201.
Sun Weidong Hansell Stedman Chen Xiaoli Wei Yu Liu Meizhen Xu Chengbin H. Lee Sweeney 《中华医学杂志(英文版)》1998,(6):495
LigasechainreactionfordiagnosisoffamilialhypertrophiccardiomyopathySunWeidong孙维东,HanselStedman,ChenXiaoli,WeiYu,LiuMeizhen,Xu... 相似文献
202.
To elucidate the mechanisms by which thiamine deficiency affects hepatic microsomal monooxygenase activities, the effect of thiamine deficiency on two constitutive cytochrome P450 isozymes, P450IIE1 and P450IIC11, was investigated, using weanling male Sprague-Dawley rats. The clinical signs of thiamine deficiency were apparent after feeding a thiamine-deficient diet for 3 weeks. Thiamine deficiency caused an increase in P450IIE1, which was determined by N-nitrosodimethylamine demethylase assay and immunoquantitation of P450IIE1. This increase in the P450IIE1 level was mainly attributed to thiamine deficiency per se but not to dietary restriction. Ketone bodies were not elevated in thiamine-deficient rats, whereas ketone bodies were elevated and may have served as inducing factors in calorically restricted pair-fed animals. Injections of pyruvate or pyrithiamine in addition to thiamine deficiency did not potentiate the induction effect. On the other hand, thiamine deficiency did not affect the level of P450IIC11 during the 3 weeks of feeding the thiamine-deficient diet. In addition, thiamine deficiency increased cytosolic glutathione S-transferase activity but not steroid isomerase activity. The present study demonstrates the specificity of thiamine deficiency per se in the induction of P450IIE1 which does not involve an increase in the ketone body level. 相似文献
203.
孙希诰 《南方医科大学学报》1990,(4)
侧脑室注射甘氨酸使健康家兔和烧伤家兔血浆皮质酮浓度降低;注射L—谷氨酸和L—天冬氨酸使健康家兔血浆皮质酮浓度升高,但不能使烧伤后升高的血浆皮质酮浓度发生改变。提示这三种氨基酸作为神经递质参与下丘脑—垂体—肾上腺皮质轴的调控。烧伤刺激通过下丘脑引起内分泌紊乱,这种紊乱与L—谷氨酸和L—天冬氨酸失控有关。 相似文献
204.
妇科腹腔镜手术几种激光对兔子宫壁损伤的实验研究 总被引:2,自引:2,他引:0
为掌握妇科腹腔镜手术所应用的激光器的治疗剂量,对几种激光引起的兔子宫壁热损伤进行观察。实验研究证实:所有激光产生的损伤程度与所用的剂量呈正相关。术后48h与即刻损伤程度相比,半导体激光的损伤程度明显加深、加宽;但CO2激光和NdYAG激光接触式光刀无显著变化。说明应用激光行妇科腹腔镜手术治疗时,所产生的损伤与应用的功率密度有关,为临床合理选用腹腔镜下的激光治疗提供依据 相似文献
205.
Hyun-Min Shin Chul-Jong Park Jong-Yuk Yi Tae-Yoon Kim Chung-Won Kim 《Pediatric dermatology》1996,13(2):146-147
Abstract: Juvenile xanthogranuloma is a xanthomatous and granulomatous condition that frequently arises before 1 year of age and mainly occurs on the head and trunk. We report a rare solitary juvenile xanthogranuloma on the right palm of a 10-year-old girl, present for one year. This solitary involvement of the palm has been reported only twice before. 相似文献
206.
日本血吸虫感染小鼠脾细胞IL—2及IFN—γ动态观察 总被引:4,自引:0,他引:4
本文观察8wk龄C57BL/6小鼠感染日本血吸虫尾蚴后不同时期脾细胞经SEA或ConA刺激,体外诱生的IL-2和IFN-γ活性变化。结果表明两种细胞因子活性均在感染后第4-6wk开始上升,第6—8wk达高峰,第12—14wk恢复至感染前水平。IFN-γ高峰时间略先于IL-2。非特异性刺激原诱生组和特异性刺激原诱生组各阶段细胞因子活性动态基本一致,前组活性高于后组。提示IFN-γ与IL-2活性与血吸虫卵肉芽肿的诱导、成熟与维持有密切关系。 相似文献
207.
The monoclonal antibody MAb 1-7-1, which specifically binds to cytochromes P-450IA1 and P-450IA2 in 3-methylcholanthrene-induced rat liver microsomes, was used to identify a cytochrome P-450IA1 homologue in human lung microsomes. Although MAb 1-7-1 had similar affinity constants for human and rat microsomes, the amount bound to human lung microsomes was severalfold lower than that bound to microsomes from untreated rat or rabbit lung and much lower than the amount bound to 3-methylcholanthrene-induced rat lung or liver microsomes. The amount bound to untreated baboon lung microsomes was similar to that bound to human lung microsomes. Three cytochrome P-450IA1-catalyzed activities, 7-ethoxyresorufin O-deethylase, 7-ethoxycoumarin, O-deethylase, and aryl hydrocarbon hydroxylase, were measurable in human lung microsomes, but the cytochrome P-450IA2-dependent activity acetanilide 4-hydroxylase was not. MAb 1-7-1 inhibited, and its binding correlated strongly with, 7-ethoxyresorufin O-deethylase activity (r = 0.92, p less than 0.01) in human lung microsomes. 7-Ethoxyresorufin O-deethylase activities in human lung were similar to those measured in untreated baboon lung but considerably lower than those present in untreated rabbit lung, untreated or 3-methylcholanthrene-induced rat lung and liver, or human liver. We conclude that MAb 1-7-1 recognizes a cytochrome P-450IA1 homologue in human lung and that no cytochrome P-450IA2 homologue is detected. Cytochrome P-450IA1 is expressed in human lung at relatively low levels, similar to those observed in untreated primate (baboon) lung. The majority of the 19 human lung samples examined do not exhibit a permanent polycyclic aromatic hydrocarbon-induced state with respect to this isozyme. 相似文献
208.
209.
系统地研究了肟类药物对塔崩抑制的大鼠脑AChE的体外重活化作用,并与梭曼、沙林和VX进行了比较。结果表明,沙林和VX抑制的AChE较易被药物重活化,而塔崩和梭曼抑制的AChE则较难。37℃、pH7.2条件下,塔崩抑制的大鼠脑AChE可浓度依赖性地被TMB_r和LuH_6重活化,2-PAM在高浓度下也有一定作用,但HI-6在所用3个浓度下均无重活化。通过降低抑制温度成功地建立了未老化的梭曼膦酰化AChE模型。药物试验表明,未老化的梭曼膦酰化大鼠脑AChE可被高浓度(1mmol/L)HI-6重活化,而不被2-PAM、TMB_4及LuH_6重活化。提示药物自身内在活性在重活化作用中的重要性。TMB_4和LuH_6对塔崩磷酸化AChE有较强重活化,而对未老化梭曼膦酸化AChE无重活化,HI-6则相反,对未老化梭曼膦酰化AChE重活化效果好,而对塔崩磷酰化AChE无重活化作用。塔崩和梭曼膦酰化AChE在未老化以前对药物的响应就有所不同,毒剂残基的空间效应可能起重要作用。 相似文献
210.