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1.
目的 建立血清中16种多环芳烃的气相色谱-串联质谱测定方法。方法 血清样经甲醇沉淀蛋白,加入正己烷与二氯甲烷混合溶剂萃取,萃取物氮吹至近干后,正己烷和二氯甲烷混合溶剂复溶,取1 μl上清液进样分析。16种待测多环芳烃经DB-5色谱柱(30 m×0.25 mm,0.25 μm)分离,多反应监测模式监测,内标法定量。结果 本法在1.0 μg/L~2.0×102 μg/L范围内线性良好,方法检出限为4.20×10-2 μg/L~0.27 μg/L,加标回收率为79.7%~108.0%,精密度为2.57%~6.76%。结论 本方法具有灵敏、快速、回收率和重复性好等优点,满足人血清中多种多环芳烃测定的要求。 相似文献
2.
目的分析维生素D(vitamin D, VitD)在降低PM2.5对肺泡上皮细胞毒性中的影响。 方法采用透射电子显微镜和激光诱导荧光分析对比VitD处理前后,PM2.5的毒性能力。MMT观察VitD处理前后细胞生存率,分析PM2.5对A549的毒性影响。 结果VitD作用后的PM2.5平均粒径减小5.5 nm,颗粒聚结和团聚更为明显,颗粒平均条纹长度增加、弯曲度减小,差异有统计学意义。PM2.5条纹间距无统计学差异,有明显减小,接近0.06 nm。VitD溶液从PM2.5解吸3环和4环多环芳香烃(polycyclic aromatic hydrocarbons, PAHs),减少PM2.5表面附着的致病性PAHs。PM2.5可引起肺上皮细胞A549生存率明显下降,给予VitD干预后,PM2.5对A549细胞生存率的抑制改善了54.7%,PM2.5的生物毒性降低。 结论VitD可减少PM2.5上吸附的致病性PAHs,抑制其致病活性,减小PM2.5对肺上皮细胞的毒性。 相似文献
3.
目的探讨酪酸梭菌对非酒精性脂肪性肝病(NAFLD)患者肠屏障的作用及其对NAFLD的疗效和作用机制。方法选择在该院消化科就诊的NAFLD患者100例纳入NAFLD组,另选取50例健康体检者纳入对照组,比较两组的肠屏障功能指标[血清内毒素、二胺氧化酶(DAO)和D-乳酸]。将NAFLD组患者按照随机数字表法又分为A组、B组,两组均予以常规低脂饮食+有氧运动+双环醇1粒tid po,A组在此基础上,予以酪酸梭菌2粒tid po。将NAFLD组根据丙氨酸氨基转移酶(ALT)值分为ALT升高组和ALT正常组,比较两组肠屏障功能障碍发生率及炎性反应指标[白细胞介素(IL)-6、肿瘤坏死因子-α(TNF-α)]水平。分别于给药1个月后复查患者肠屏障功能、血脂[三酰甘油(TG)、总胆固醇(TC)]、肝功能、炎性反应指标等,并对A组与B组患者以上指标进行比较。结果NAFLD组的血清内毒素、DAO、D-乳酸水平均高于对照组,差异有统计学意义(P<0.05)。ALT升高组的TNF-α、IL-6水平明显高于ALT正常组,差异有统计学意义(P<0.05)。用药后A组与B组内毒素、D-乳酸、DAO水平均较用药前下降,A组下降比B组更明显,差异有统计学意义(P<0.05)。用药后A组与B组IL-6、TNF-α、TG水平均较用药前下降,A组下降比B组更明显,差异有统计学意义(P<0.05)。A组的总有效率(86.0%)高于B组(70.0%),差异有统计学意义(P<0.05)。结论NAFLD患者存在肠屏障损伤,可能与炎性反应激活有关。联合酪酸梭菌治疗有助于改善NAFLD患者的肠屏障功能,降低血脂水平,提高疗效。 相似文献
4.
目的 为筛选高活性的蛇足石杉铜胺氧化酶(copper-containing amine oxidase,CAO),通过生物工程方法实现石杉碱甲(huperzine A,HupA)的合成、为加快新药创制进度提供理论依据。方法 基于蛇足石杉转录组测序得到的CAO序列片段,利用cDNA末端快速扩增技术(rapid amplification of cDNA ends,RACE)技术,扩增、拼接并验证获得该基因的全长cDNA序列,并将其命名为HsCAO2。结果 通过RACE技术得到HsCAO2的cDNA全长为2696 bp,CDS为2199 bp,编码732个氨基酸。氨基酸序列同源性比对发现,HsCAO2具有保守的氨基酸位点和Cu2+结合位点;进化树分析结果表明,HsCAO2与蛇足石杉中的另一个CAO(HsCAO1)同源性最高,达91.67%;蛋白质结构分析结果表明,HsCAO2也可能在生物体里以同源二聚体的形式存在。在此基础上,进一步分别构建了超表达载体pOX-HsCAO2和体外蛋白表达载体pET-28a (+)-HsCAO2。结论 HsCAO2很可能是蛇足石杉中的一个新的功能性CAO,且超表达载体和体外蛋白表达载体的成功构建为进一步研究其功能奠定了基础。 相似文献
5.
ObjectivesTo investigate the possible influence of polycyclic aromatic hydrocarbons (PAHs) exposure on neurodevelopment of toddlers at the age of 12 months.MethodsTotally 306 subjects were recruited from the Qingdao Birth Cohort established in 2014. PAH-DNA adducts in toddlers’ umbilical cord blood samples, hydroxyl-PAH metabolites in their urine samples and the developmental quotients (DQs) were measured. Sex, gestational age, birth weight, and maternal educational background were adjusted to analyze the influence of the PAH exposure on the neurodevelopment of the toddlers using multivariate linear regression model.ResultsPearson correlation test showed that the logarithmic values of hydroxyl-PAH were negatively correlated with the DQs. Multivariate linear regression analysis indicated that logarithmic concentration of 1(9)- hydroxyphenanthrene was still associated with the DQs of the fine motor behaviors with β and 95% confidential interval (CI) of -1.137 (-2.053, -0.222), together with PAH-DNA adducts [β (95% CI): -0.577 (-0.930, -0.225)]. PAH-DNA adducts presented an independently negative influence on the DQs of the gross motor and personal social behaviors with β (95%CI) of -0.470 (-0.814, -0.126) and -0.526 (-0.859, -0.193), respectively.ConclusionsThe exposure to PAHs in toddlers at 12 months could influence their neurodevelopment. Additionally, prenatal exposure to PAHs should also be considered. 相似文献
6.
7.
Ulrike Luderer Matthew J. Meier Gregory W. Lawson Marc A. Beal Carole L. Yauk Francesco Marchetti 《Environmental and molecular mutagenesis》2019,60(5):410-420
Polycyclic aromatic hydrocarbons like benzo[a]pyrene (BaP) are ubiquitous environmental contaminants formed during incomplete combustion of organic materials. Our prior work showed that transplacental exposure to BaP depletes ovarian follicles and increases prevalence of epithelial ovarian tumors later in life. We used the MutaMouse transgenic rodent model to address the hypothesis that ovarian mutations play a role in tumorigenesis caused by prenatal exposure to BaP. Pregnant MutaMouse females were treated with 0, 10, 20, or 40 mg/(kg day) BaP orally on gestational days 7–16, covering critical windows of ovarian development. Female offspring were euthanized at 10 weeks of age; some ovaries with oviducts were processed for follicle counting; other ovaries/oviducts and bone marrow were processed for determination of lacZ mutant frequency (MF). Mutant plaques were pooled within dose groups and sequenced to determine the mutation spectrum. BaP exposure caused highly significant dose-related decreases in ovarian follicles and increases in ovarian/oviductal and bone marrow mutant frequencies at all doses. Absence of follicles, cell packets, and epithelial tubular structures were observed with 20 and 40 mg/(kg day) BaP. Depletion of ovarian germ cells was inversely associated with ovarian MF. BaP induced primarily G > T and G > C transversions and deletions in ovaries/oviducts and bone marrow cells and produced a mutation signature highly consistent with that of tobacco smoking in human cancers. Overall, our results show that prenatal BaP exposure significantly depletes ovarian germ cells, causes histopathological abnormalities, and increases the burden of ovarian/oviductal mutations, which may be involved in pathogenesis of epithelial ovarian tumors. Environ. Mol. Mutagen. 60:410–420, 2019. © 2018 Her Majesty the Queen in Right of Canada 相似文献
8.
Catherine R. Sears 《Respiratory investigation》2019,57(2):111-121
Cigarette smoking is the leading cause of lung cancer and chronic obstructive pulmonary disease (COPD). Many of the detrimental effects of cigarette smoke have been attributed to the development of DNA damage, either directly from chemicals contained in cigarette smoke or as a product of cigarette smoke-induced inflammation and oxidative stress. In this review, we discuss the environmental, epidemiological, and physiological links between COPD and lung cancer and the likely role of DNA damage and repair in COPD and lung cancer development. We explore alterations in DNA damage repair by DNA repair proteins and pathways. We discuss emerging data supporting a key role for the DNA repair protein, xeroderma pigmentosum group C (XPC), in cigarette smoke-induced COPD and early lung cancer development. Understanding the interplay between cigarette smoke, DNA damage repair, COPD, and lung cancer may lead to prognostic tools and new, potentially targetable, pathways for lung cancer prevention and treatment. 相似文献
9.
基于分子对接技术虚拟筛选延胡索抗心肌缺血物质基础研究 总被引:5,自引:3,他引:2
目的研究延胡索抗心肌缺血的物质基础及作用机制。方法通过TCMSP平台筛选到符合条件的目标小分子化合物,运用Maesrto11.1分子对接软件筛选延胡索中与相应靶点蛋白对接较好的小分子化合物,再运用Cytoscape3.6.1构建多成分-靶点网络药理图,通过拓扑学分析,阐释其网络特征。结果在16种心肌缺血靶点对接结果中,8种季铵碱化合物、1种黄酮类、2种叔胺碱类显示出了较好的对接结果。季铵碱类化合物和黄酮类槲皮素对接结果普遍优于叔胺碱类,对接结果中季铵碱打分平均值高于叔胺碱的靶点蛋白有10种。网络药理学结果分析得知多化合物-靶点的网络异质性为0.57,平均相邻节点数3.59,特征网络长度3.02,网络中心度0.21。结论延胡索季铵碱类化合物黄连碱、巴马汀、去氢紫堇鳞茎碱、药根碱、非洲防己碱、小檗碱,黄酮类槲皮素可能是其治疗心肌缺血的物质基础,延胡索治疗心肌缺血是多成分与多靶点相互作用的结果。 相似文献
10.
Sheng-Wei Wang Kuo-Hsien Hsu Shou-Chieh Huang Su-Hsiang Tseng Der-Yuan Wang Hwei-Fang Cheng 《Yao wu shi pin fen xi = Journal of food and drug analysis.》2019,27(3):815-824
A gas chromatography coupled with tandem mass spectrometry (GC-MS/MS) method is developed to determine 18 representative polycyclic aromatic hydrocarbons (PAHs) in cosmetics, including Benzo[a]pyrene (BaP) and others. The method offers high sensitivity and selectivity under selected reaction monitoring (SRM) mode to satisfy the requirements of both quantitation and qualitation. The extraction solvent system used in this study is acetone/hexane 1:1 (v/v) and other purification procedure is unnecessary. The linearities of 18 PAHs are validated in different concentration in the range of 0.25–20 ng/mL individually with coefficient correlation (r) higher than 0.996. The recoveries for spiking 3 different concentrations are from 87.40% to 120.44% for 18 PAHs and the coefficient of variation (CV) are below 12.32%. Limit of quantification (LOQ) of 18 PAHs is in the range of 0.05–0.2 mg/kg. A matrix enhancement effect is observed and can be compensated with deuterated internal standard. The method has been successfully applied to 73 samples, over 40 of them are lipsticks. The results show none of the samples detect Benzo[a]pyrene (BaP) and Dibenzo[a,h]anthracene (DBA), both are classified as the most carcinogenic. 8 PAHs are detected and the average value between 0.08 and 0.27 mg/kg. This study offers a sensitive and simple method to analyze 18 representative PAHs successfully and can be applied to cosmetic products and raw materials. 相似文献