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21.
Study on Metabolites of Aconitum Alkaloids in Human Urine 总被引:1,自引:0,他引:1
ForMaster‘sDegree:SUNYing Supervisor:Prof.ZHANGHong-gui ZHONGda-fang ZHANGHan-qi 《中国药学》2003,12(1):54-55
TheaconitebelongstoplantsofgenusAconituminfamilyofRanunculaceaandhavenotableclinicalfunctionsintreatingrheumaticarthritis ,heartfailure ,etc .However,accidentsofaconitine(fromaconite)poisoningfrequentlyoccurtomanypeopletakingtheseherbs .Theplantsofthisfamilycontainaconitine ,mesaconitine ,hypaconitineandotheraco nitumalkaloids .Theyarehighlytoxic ,andtheirtreatmentdoseapproachestothetoxicdoseorlethaldose .Duringtheperiodfrom 1989- 1995 ,morethan 30casesofpoisoningcausedbyaconitineinsometradit… 相似文献
22.
Individuals chronically exposed to low levels of organophosphate insecticides may present with subtle impairments in cognition. In addition, low level diisopropylflurophosphate (DFP) exposure (0.25 mg/kg per day for 2 weeks) in rats resulted in protracted working memory impairment [29]. The current studies attempt to show a temporal relationship between the DFP-induced impairment in performance of a spatial memory task and the protracted decrease in the expression of cholinergic receptors and acetylcholinesterase in specific brain regions. Cholinergic receptors labeled with the ligands [(3)H]epibatidine and [(3)H]AFDX-384 were affected to a much greater extent and for a longer period of time than were both acetylcholinesterase activities and cholinergic receptors labeled with [(3)H]QNB. Pre-testing administration of nicotine was shown to completely reverse this DFP-induced impairment in memory-related task performance. Additionally, prophylaxis with pyridostigmine bromide (PB) caused DFP-treated animals to exhibit near normal levels of memory-related task performance. These results are consistent with the development of a protracted phase of learning impairment to sub-acute DFP exposure, which may involve the loss of hippocampal nicotinic receptors, and may be prevented or reversed by PB or nicotine, respectively. 相似文献
23.
目的:观察孕期大鼠摄入不同剂量的氟之后,对子代鼠血液和骨氟浓度及软骨细胞和骨关节结构的影响,以探索通过妊娠期母体给氟预防乳牙龋齿的新途径。方法:给妊娠SD大鼠分别用N aF按1 m g/kg体重、10 m g/kg体重和50 m g/kg体重灌胃至分娩,并用0.9%N aC l灌胃作为对照组。结果:①实验组各组子鼠血清中的氟化物含量均较对照组高(P<0.01);并且与母鼠摄入的氟剂量呈正相关。②在中、高剂量组子鼠上肢骨骨氟的含量明显高于对照组。③在高剂量组子鼠的上肢骨切片中可见软骨细胞和关节结构的破坏。结论:①妊娠期母体摄入的氟化物可进入其子体体内。②当母鼠摄入的氟化物剂量过高时,可引起骨组织的毒性损害。 相似文献
24.
纳洛酮治疗急性酒精中毒46例疗效观察 总被引:2,自引:2,他引:2
目的:总结纳洛酮(naloxone)治疗急性酒精中毒的疗效和经验。方法:对用纳洛酮治疗的46急性酒精中毒患者的临床资料进行分析。结果:纳洛酮治疗轻、中度患者症状消失时间为(0.6±0.1)小时,重度中毒患者神志清醒时间为(3.0±0.3)小时,与传统的治疗相比有明显的优势。结论:纳洛酮是治疗急性酒精中毒的有效药物,使用简单,疗效快速可靠。 相似文献
25.
毒死蜱(chlorpyrifos,CPF)是一种广泛使用的有机磷农药,其对人类健康和生态系统的潜在风险已引起广泛关注。CPF主要通过抑制乙酰胆碱酯酶(AChE)发挥杀虫作用,但越来越多的研究表明,CPF的毒性作用远不止于此,也与氧化应激、炎症反应、 细胞死亡等多种生物学过程密切相关,因而可能导致神经退行性疾病、生殖发育障碍以及其他慢性健康问题。核因子红细胞2相关因子2(Nrf2)作为一种关键的抗氧化应激调节因子,具有显著的保护作用。本文旨在综述Nrf2在调节CPF诱导的氧化应激、神经毒性、细胞死亡和炎症反应中的作用机制,探讨其作为潜在治疗靶点的前景,以为开发新的CPF中毒治疗策略提供理论基础。 相似文献
26.
目的 分析急性生理与慢性健康状况系统Ⅱ(APACHEⅡ)评分与重度有机磷中毒患者肠道屏障功能的相关性.方法 回顾性选取2017年1月至2019年12月安徽理工大学附属亳州市人民医院收治的119例重度有机磷中毒患者.按照患者预后情况,将患者分别纳入存活组80例、病死组39例.记录患者入院即刻及入院48、72、144 h ... 相似文献
27.
稀有元素铊对人体的毒性因一系列中毒事件的出现而广受重视。近10年来,铊中毒的作用机制和救治措施成为研究热点。初步研究表明,铊经胃肠道、呼吸道和皮肤吸收后,在体内广泛分布,浓度最高的是肾脏,其次为唾液腺。以离子状态存在的铊可以取代体内的钾离子,影响钾离子参与的生理功能及神经信号传导,并影响一系列酶的活性,使之失去正常功能。此外,铊还能拮抗钙离子,从而影响心脏功能、与核黄素结合干扰生物氧化等途径。在临床上,铊中毒可见周围神经中毒症状、胃肠道症状、黏膜炎症、毛发脱落和视力受损等。24h尿液中铊浓度检测为评价铊中毒的最佳方法,尿铊〉5μg/L具有诊断意义。当前临床治疗措施主要是减少吸收、加速清除和对症治疗。最新研究表明,血液灌流能有效清除已吸收的铊。 相似文献
28.
Li Jun Cheng Xiaotian Wang Zhenghui Wen Xinping Han Lingling Sang Zhiping Zhang Jie Duan Hushun Liang Binfeng Gao Jianguo 《Frontiers of Medicine in China》2007,1(2):219-222
This study aimed to describe the distribution of water-arsenic (As) valence states and its relationship to areas with endemic
arsenism in the Datong basin. Drinking water samples of patients with endemic arsenism and a control group were examined using
hydride generation atomic fluorescence spectrometry (HG-AFS). We analyzed the data using SPSS10.0 for Windows. The As(III)/As
ratio was 52.1% in the water sample, exceeding the national standard of 0.05 mg/L. The As(III)/As ratio significantly varied
among the different stages in the disease-state groups, and with the control group (χ
2 = 22.4, P<0.01). The As(III)/As(V) ratio significantly varied in the four groups (χ
2 = 26.19, P<0.01), with a tendency to increase along with the seriousness of the disease state. The most common type of drinking water
arsenic valence state was As(III) in the endemic disease-areas. Endemic arsenism was positively correlated with As(III). This
led us to conclude that the fraction of each water-arsenic valence state should be studied when determining the arsenic content
of drinking water.
Translated from Chinese Journal of Endemiology, 2006, 25(1): 64–66 [译自: 中国地方病学杂志] 相似文献
29.
Lucia Bernasconi Benedetta Brolli Aurelio Negro Jorge L Zoino Azzurra Schicchi Valeria M Petrolini Davide Lonati Anna Ronchi Carlo A Locatelli 《La Medicina del lavoro》2022,113(2)
Introduction:Most of the molybdenum (Mo) is used in metallurgical applications, the tetrathiomolybdate form is an experimental chelating agent for Wilson’s disease. Human data of acute Mo exposure are lacking and, no report of no-observed-adverse-effect level (NOAEL) has been described until now.Case study:We report a case of acute occupational exposure to molybdenum, with the related plasma and urine molybdenum concentrations, caused by an accidental ingestion of a sip of an anti-corrosion liquid for metal containing sodium molybdate. Our purpose was to evaluate potential systemic toxicity of molybdenum and to evaluate the dose-response/dose-effect relationship. We estimated the amount of ingested molybdenum to make a mg/kg relationship and performed repeated urine and plasma molybdenum determinations. The patient was hospitalized for three days to monitor possible development of acute symptoms/biochemical alterations.Discussion:We estimated the amount of the sip around 50 ml, with an estimation of a total of 5 gr of sodium molybdate that, for the patient bodyweight of 80 kg, would mean 62,5 mg/kg of ingested Mo. Blood and urine samples collected 2 hours after ingestion showed 50 mcg/L (reference range: 0.43 – 1.8 mcg/L) and 630 mcg/L (refence range: up to 116 mcg/L) of Mo respectively, confirming acute exposure. The patients remained asymptomatic confirming that an estimated oral dose of Mo of 62.5 mg/kg was not associated with adverse effects.Conclusions:Our value, being extrapolated by a single case, will require further confirmations from other studies to allow a full evaluation of a NOAEL. Nevertheless, it does not preclude its use in evaluating the probable absence of adverse effect in the context of acute Mo exposure. 相似文献
30.