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81.
Bisphenol A (BPA), a well-recognized anthropogenic xenoestrogen, has been identified as a causative agent responsible for inducing carcinogenicity, cognitive impairment, neurotoxicity, oxidative stress, etc. However, BPA-induced neurotoxicity and its possible amelioration through natural compound intervention remain elusive. The current study was performed to elucidate the neurotoxic potential of BPA in zebrafish (Danio rerio) by waterborne exposure and its possible amelioration by quercetin co-supplementation. Protective effect of quercetin against BPA-induced altered neurobehavioral response, oxidative stress and neuromorphological changes were evaluated in zebrafish brain. The present findings reveal that BPA-induced altered neurobehavioral response was ameliorated by quercetin. Biochemical studies advocate the potential therapeutic efficacy of quercetin against BPA-induced oxidative stress in zebrafish brain. Quercetin also shows neuroprotection against BPA-induced augmented neuronal pyknosis in periventricular grey zone (PGZ) of zebrafish brain. These basic findings indicate that quercetin may act as an effective intervention against BPA-induced neurotoxicity in zebrafish through down-regulation of oxidative stress.  相似文献   
82.
Modes of interactions of small ligands with CYP3A4 have been defined using the Template established in our previous studies (DMPK. 34: 113–125 2019 and 34 351–364 2019). Interactions of polyaromatic hydrocarbons such as benzo[a]pyrene, pyrene and dibenzo[a,j]acridine were refined with the idea of Right-side movement of ligands at Rings A and B of Template. Expected formation of metabolites from the placements faithfully matched with experimentally observed sites of their metabolisms and also with preferred orders of regio-isomeric metabolite abundances in recombinant CYP3A4 system. In comparison of CYP3A4-ligand data with the placements on simulations, a futile sitting of non-substituted and free rotatable phenyl structures was suggested as a cause of poor oxidations of the phenyl parts of CYP3A4 ligands. These data were in turn indicative of the role of the rotation-ceasing action for the function. Typical inhibitors, ketoconazole, nicardipine, mibefradil and GF-I-1 shared mutuality on their sittings, in which the inhibitor molecules hold a CYP3A4 residue from dual sides on Template. In addition, clotrimazole would be stuck between facial- and rear-side walls of CYP3A4 and interact with ferric iron through nitrogen atom of the imidazole part. These data offered structural bases of CYP3A4-inhibitory actions of ligands.  相似文献   
83.
徐琳  路苹  姚红梅  张翊玲 《中国全科医学》2020,23(24):3034-3039
背景 支气管扩张症是呼吸系统常见病、多发病,感染是引起支气管扩张症的最常见原因。人分泌型磷脂酶A2-X(sPLA2-X)在炎性反应中发挥重要作用,并可促进炎性反应的发生、发展,而支气管扩张症合并感染患者血清sPLA2-X表达情况及其与重要炎性指标如降钙素原(PCT)、C反应蛋白(CRP)、诱导型一氧化氮合酶(iNOS)、白介素(IL)-6、IL-17、IL-33是否存在相关性尚未见相关报道。目的 研究支气管扩张症合并感染患者血清sPLA2-X表达情况及其与炎性指标--PCT、CRP、iNOS、IL-6、IL-17、IL-33的相关性,并进一步研究血清sPLA2-X对支气管扩张症合并感染的影响。方法 选取2017年2月-2019年1月在贵州省人民医院呼吸与危重症医学科住院治疗的支气管扩张症合并感染患者47例为病例组,选取同期在贵州省人民医院健康体检中心体检的健康志愿者21例为健康对照组。收集研究对象一般资料,分别检测健康对照组体检当天、观察组治疗前(入院当天)与治疗后(出院前1天)血清sPLA2-X、白细胞计数、PCT、CRP、iNOS、IL-6、IL-17、IL-33。比较两组治疗前后观察指标,分析病例组治疗前血清sPLA2-X与PCT、CRP、iNOS、IL-6、IL-17、IL-33的相关性。结果 病例组治疗前血清sPLA2-X、白细胞计数、PCT、CRP、iNOS、IL-6、IL-17、IL-33均高于健康对照组(P<0.05);病例组治疗后血清sPLA2-X、PCT、CRP、iNOS、IL-17均高于健康对照组(P<0.05);两组治疗后白细胞计数、IL-6、IL-33比较,差异无统计学意义(P>0.05)。病例组治疗后血清sPLA2-X、白细胞计数、PCT、CRP、iNOS、IL-6、IL-17、IL-33均低于本组治疗前(P<0.05)。病例组治疗前血清sPLA2-X与PCT、CRP、iNOS、IL-6、IL-17、IL-33均呈正相关(r=0.526 2、 0.640 1、0.550 7、0.516 8、0.609 9、0.357 4,P值均<0.01)。结论 支气管扩张症合并感染患者血清sPLA2-X升高,且其与PCT、CRP、iNOS、IL-6、IL-7、IL-33呈正相关,表明血清sPLA2-X与支气管扩张症合并感染有重要的关联,血清sPLA2-X可作为评估支气管扩张症合并感染的参考指标。  相似文献   
84.
MOB kinase activator 1A (MOB1A) plays an important role in many diseases and cancers. Here, we observed that MOB1A was substantially overexpressed in gallbladder carcinoma (GBC) tissues compared with nontumor tissues. The high expression of MOB1A was closely associated with poor survival in patients with GBC at advanced TNM stages. Furthermore, our study indicated that MOB1A promoted autophagy by activating the IL6/STAT3 signaling pathway and regulating the chemosensitivity to gemcitabine under glucose deprivation conditions both in vitro and in vivo. In conclusion, these findings suggested that MOB1A is critical for the development of GBC via the MOB1A-IL6/STAT3-autophagy axis.  相似文献   
85.
谢峻  张静怡  汤宁  柯江英  赵嵩  姜泽慧 《中草药》2020,51(3):812-820
植物来源的加兰他敏、石杉碱甲等乙酰胆碱酯酶抑制剂(AChEIs)以其高效低毒的优势成为当前临床治疗阿尔茨海默病的主流药物。由于目前加兰他敏、石杉碱甲等AChEIs尚未实现工业规模化合成,故仍主要依赖植物提取。然而,药源植物培育周期长、难度大,药效物质含量低,随着社会需求的急剧攀升,供求矛盾日益突出。开发新替代资源以及利用现代基因工程技术合成加兰他敏、石杉碱甲等AChEIs是缓解当前矛盾的有效途径。对近年来加兰他敏和石杉碱甲生物合成的相关研究进展进行综述,总结了替代资源的开发研究现状,以期为挖掘加兰他敏、石杉碱甲等AChEIs优势新资源及利用代谢工程合成药效物质研究提供参考。  相似文献   
86.
87.
IFN-α/β是机体对抗外来病原体的第一道防线,其产生和后续激活的细胞信号转导可诱导具有抑制病毒感染和复制作用的IFN刺激基因的表达。然而,大多数病毒可通过表达一种或多种蛋白抵抗宿主细胞的抗病毒反应。流感病毒非结构蛋白1(nonstructural protein 1,NS1)作为多功能毒力因子,在流感病毒感染过程中起重要作用。此文概述了NS1的结构与功能及抑制IFN-α/β产生和抗病毒效应作用的机制,为研究流感病毒致病机理提供参考。  相似文献   
88.
目的 探索布鲁氏杆菌A19疫苗株全基因组的结构、分子生物学的功能,并对其生物信息学进行研究。方法 采用Illumina Hiseq 4000和PacBio对A19进行全基因组测序,并与GenBank 上的8株菌进行比较基因组学解析。A19基因组3 286 167 bp, 预测3 371个基因,GC含量57.25%。通过注释COG库,对应基因有2 560个,将其归入22类COG中;根据比对KEGG库,得到2 544个基因,共参与33类代谢通路。结果 综合两个数据库结果发现,大多数A19预测基因中的基因功能主要与膜运输、氨基酸转运及碳水化合物代谢有关。结论 通过分析发现, A19和猪羊牛种布鲁氏菌之间存在一定差异,并找出牛种毒力基因。本实验通过测序A19全基因组,为布鲁菌疫苗的研究提供思路。  相似文献   
89.
1. Cytochrome P450 3A4 (CYP3A4) is an important member of the cytochrome P450 enzyme superfamily, with 33 allelic variants reported previously. Genetic polymorphisms of CYP3A4 can produce a significant effect on the efficacy and safety of some drugs, so the purpose of this study was to clarify the catalytic characteristics of 22 CYP3A4 allelic isoforms, including 6 novel variants in Han Chinese population, on the oxidative metabolism of amiodarone in vitro.

2. Wild-type CYP3A4*1 and other variants expressed by insect cells system were incubated respectively with 10–500?μM substrate for 40?min at 37?°C and terminated at ?80?°C immediately. Then these samples were treated as required and detected with ultra-performance liquid chromatography-tandem mass spectrometry used to analyze its major metabolite desethylamiodarone.

3. Among the 21 CYP3A4 variants, compared with the wild-type, the intrinsic clearance values (Vmax/Km) of two variants were apparently decreased (11.07 and 2.67% relative clearance) while twelve variants revealed markedly increased values (155.20~435.96%), and the remaining of seven variants exhibited no significant changes in enzyme activity.

4. This is the first time report describing all these infrequent alleles for amiodarone metabolism, which can provide fundamental data for further clinical studies on CYP3A4 alleles.  相似文献   

90.
1.?Schizandrol A is an active component in schisandra, also the representative component for the identification of schisandra.

2.?A rapid resolution liquid chromatography coupled with quadruple–time–of–flight mass spectrometry (RRLC–QTOF/MS) was developed to investigate the pharmacokinetics of schizandrol A after its intragastric administration (50?mg/kg) in rats.

3.?Schizandrol A was rapidly absorbed (T max = 2.07?h), with a longer duration (t 1/2 = 9.48?h) and larger apparent volume of distribution (Vz/F?=?111.81?l/kg) in rats. Schizandrol A can be detected in main organs and the order of its distribution was in the liver?>?kidney?>?heart?>?spleen?>?brain, particularly higher in the liver.

4.?Five schizandrol A metabolites were identified, including 2–demethyl–8(R)–hydroxyl–schizandrin, 3–demethyl–8(R)–hydroxyl–schizandrin, hydroxyl–schizandrin, demethoxy–schizandrin, 2, 3–demethyl–8(R)–hydroxyl–schizandrin, indicating that the hydroxylation and demethylation may be the major metabolic way of schizandrol A.

5.?This study defined the pharmacokinetic characteristics of schizandrol A in vivo, and the RRLC–QTOF/MS is more sensitive and less limited by conditions, and needs less samples, which may be a useful resource for the further research and development of schisandrol A.  相似文献   

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