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991.
992.
Yi-Ming Tian Jing-Feng Cao Dong-Hui Zhou Feng-Cai Zou Qiang Miao Zi-Li Liu Bi-Feng Li Rui-Qing Lv Xiao-Peng Du Xing-Quan Zhu 《Acta tropica》2014
Chlamydia spp. are obligate intracellular bacteria distributed globally, known to cause various forms of diseases in animals and humans. To date, there is limited information about the seroprevalence of Chlamydia and the risk factors associated with Chlamydia infection in dogs in the world. In the present study, a serological survey was undertaken to examine the seroprevalence and risk factors associated with dog chlamydiosis in Yunnan Province, southwestern China. A total of 591 dogs were sampled, antibodies to Chlamydia were determined by indirect hemagglutination assay (IHA). The overall seroprevalence was estimated at 17.6%. The risk factors associated with seroprevalence were determined by a multivariate logistic regression analysis. Gender and age of dogs were not significant in the logistic regression analysis (P > 0.05) and left out of the final model. Type and geographical origin of dogs were considered as main risk factors associated with Chlamydia infection, stray dogs (31.37%) were more than 16 times (OR = 16.167, 95% CI = 6.283–41.599, P < 0.01) at risk of acquiring the infection compared to the police dogs (7.62%), while pet dogs (14.41%) had a 3 times (OR = 2.968, 95% CI = 1.349–6.529, P = 0.007) higher risk. Positive dogs were found in 5 districts of Yunnan Province with prevalence ranging from 2.56% to 31.67% except Diqing (0/56). Dogs in Kunming (20.21%) had a 9 times higher risk of being seropositive compared to dogs in Lijiang (2.56%) (OR = 9.057, 95% CI = 1.211–67.714, P = 0.032), although no regional differences were found in other 4 administrative divisions compared to Lijiang (P > 0.05). Our study revealed a widespread and high prevalence of Chlamydia infection in dogs in Yunnan Province, southwestern China, with higher exposure risk in stray dogs and distinct geographical distribution. These findings suggest the potential importance of dogs in the transmission of zoonotic Chlamydia infection, and thus Chlamydia should be taken into consideration in diagnosing dog diseases. 相似文献
993.
目的:系统评价左旋氨氯地平联合一线降压药治疗高血压的疗效,为临床提供循证依据。方法:计算机检索Ovid Medline、EMBase、Cochrane Library、CNKI、CBM、VIP和WanFang Data,检索时限均从建库至2017年12月,对每项纳入研究进行偏倚风险评价,并采用Rev Man 5.3软件进行Meta分析。结果:共纳入147个RCTs,Meta分析结果显示:(1)左旋氨氯地平联合ACEI在SBP降低值[SMD=0.92,95% CI(0.79,1.04),P < 0.000 01],DBP降低值[SMD=0.87,95% CI(0.72,1.03),P < 0.000 01]和总有效率[RR=1.23,95% CI(1.20,1.26),P < 0.000 01]方面均优于对照组,差异具有统计学意义;(2)左旋氨氯地平联合ARB在SBP降低值[SMD=1.29,95% CI(1.10,1.48),P < 0.000 01],DBP降低值[SMD=0.94,95% CI(0.79,1.09),P < 0.000 01]和总有效率[RR=1.22,95% CI(1.20,1.25),P < 0.000 01]方面均优于对照组,差异具有统计学意义;(3)左旋氨氯地平联合β受体拮抗剂在SBP降低值[SMD=0.88,95% CI(0.39,1.36),P=0.000 5],DBP降低值[SMD=0.80,95% CI(0.35,1.25),P=0.000 5]和总有效率[RR=1.18,95% CI(1.12,1.23),P < 0.000 01]方面优于对照组,差异具有统计学意义;(4)左旋氨氯地平联合利尿剂在SBP降低值[SMD=1.34,95% CI(0.78,1.90),P < 0.000 01],DBP降低值[SMD=0.72,95% CI(0.20,1.24),P=0.007]方面优于对照组,差异具有统计学意义。结论:基于现有临床证据,左旋氨氯地平联合一线降压药降压效果优于单一用药方案。 相似文献
994.
Canzhan Zhu Wanjing Li Xinhong Wang Jiahong Xue Ling Zhao Yafan Song Tian Zhou Mingjuan Zhang 《Drug development research》2019,80(4):453-460
Myocardial infarction (MI) is indicated by the symptoms like sharp chest pain, sweating, palpitations, and nervousness finally leading to heart attack. MI occurs mainly due to the risk factors like smoking, elevated blood pressure, diabetes, hypercholesterolemia, obesity, decreased HDL level, elevated LDL level, hyperlipoproteinemia and aging consequently leads to demandable coronary blood supply, oxidative stress, and acute necrosis of the myocardium. Cardioprotective potential of the phloroglucinol (PG) was assessed by treating isoprenaline hydrochloride (ISO; 85 mg/kg b.w., s.c.) induced MI model in rats. Pretreatment with PG in a dose of 30 mg/kg was done for 28 days and followed by ISO (for MI induction) on 29th and 30th days, exhibited decline in the abnormalities in the ECG patterns, cardiac marker enzymes, enzymic and nonenzymic antioxidants, lipid peroxidation, lipid profiles, and histopathological investigations compared to isoprenaline alone treated group. On the whole, the present investigations elucidate the significance of PG in alleviating the pathological process and appreciably prevent the induction of MI in experimental rats. 相似文献
995.
Gang Sheng Hongtu Zhao Jiuyu Wang Yu Rao Wenwen Tian Daan C. Swarts John van der Oost Dinshaw J. Patel Yanli Wang 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(2):652-657
We report on crystal structures of ternary Thermus thermophilus Argonaute (TtAgo) complexes with 5′-phosphorylated guide DNA and a series of DNA targets. These ternary complex structures of cleavage-incompatible, cleavage-compatible, and postcleavage states solved at improved resolution up to 2.2 Å have provided molecular insights into the orchestrated positioning of catalytic residues, a pair of Mg2+ cations, and the putative water nucleophile positioned for in-line attack on the cleavable phosphate for TtAgo-mediated target cleavage by a RNase H-type mechanism. In addition, these ternary complex structures have provided insights into protein and DNA conformational changes that facilitate transition between cleavage-incompatible and cleavage-compatible states, including the role of a Glu finger in generating a cleavage-competent catalytic Asp-Glu-Asp-Asp tetrad. Following cleavage, the seed segment forms a stable duplex with the complementary segment of the target strand.Argonaute (Ago) proteins, critical components of the RNA-induced silencing complex, play a key role in guide strand-mediated target RNA recognition, cleavage, and product release (reviewed in refs. 1–3). Ago proteins adopt a bilobal scaffold composed of an amino terminal PAZ-containing lobe (N and PAZ domains), a carboxyl-terminal PIWI-containing lobe (Mid and PIWI domains), and connecting linkers L1 and L2. Ago proteins bind guide strands whose 5′-phosphorylated and 3′-hydroxyl ends are anchored within Mid and PAZ pockets, respectively (4–7), with the anchored guide strand then serving as a template for pairing with the target strand (8, 9). The cleavage activity of Ago resides in the RNase H fold adopted by the PIWI domain (10, 11), whereby the enzyme’s Asp-Asp-Asp/His catalytic triad (12–15) initially processes loaded double-stranded siRNAs by cleaving the passenger strand and subsequently processes guide-target RNA duplexes by cleaving the target strand (reviewed in refs. 16–18). Such Mg2+ cation-mediated endonucleolytic cleavage of the target RNA strand (19, 20) resulting in 3′-OH and 5′-phosphate ends (21) requires Watson–Crick pairing of the guide and target strands spanning the seed segment (positions 2–2′ to 8–8′) and the cleavage site (10′–11′ step on the target strand) (9). Insights into target RNA recognition and cleavage have emerged from structural (9), chemical (22), and biophysical (23) experiments.Notably, bacterial and archaeal Ago proteins have recently been shown to preferentially bind 5′-phosphoryated guide DNA (14, 15) and use an activated water molecule as the nucleophile (reviewed in ref. 24) to cleave both RNA and DNA target strands (9). Structural studies have been undertaken on bacterial and archaeal Ago proteins in the free state (10, 15) and bound to a 5′-phosphorylated guide DNA strand (4) and added target RNA strand (8, 9). The structural studies of Thermus thermophilus Ago (TtAgo) ternary complexes have provided insights into the nucleation, propagation, and cleavage steps of target RNA silencing in a bacterial system (9). These studies have highlighted the conformational transitions on proceeding from Ago in the free state to the binary complex (4) to the ternary complexes (8, 9) and have emphasized the requirement for a precisely aligned Asp-Asp-Asp triad and a pair of Mg2+ cations for cleavage chemistry (9), typical of RNase H fold-mediated enzymes (24, 25). Structural studies have also been extended to binary complexes of both human (5, 6) and yeast (7) Agos bound to 5′-phosphorylated guide RNA strands.Despite these singular advances in the structural biology of RNA silencing, further progress was hampered by the modest resolution (2.8- to 3.0-Å resolution) of TtAgo ternary complexes with guide DNA (4) and added target RNAs (8, 9). This precluded identification of water molecules coordinated with the pair of Mg2+ cations, including the key water that acts as a nucleophile and targets the cleavable phosphate between positions 10′-11′ on the target strand. We have now extended our research to TtAgo ternary complexes with guide DNA and target DNA strands, which has permitted us to grow crystals of ternary complexes that diffract to higher (2.2–2.3 Å) resolution in the cleavage-incompatible, cleavage-compatible, and postcleavage steps. These high-resolution structures of TtAgo ternary complexes provide snapshots of distinct key steps in the catalytic cleavage pathway, opening opportunities for experimental probing into DNA target cleavage as a defense mechanism against plasmids and possibly other mobile elements (26, 27). 相似文献
996.
997.
目的:探讨失效模式和影响分析(failure mode and effect analysis,FMEA)在降低自动口服摆药机调剂差错风险中的应用。方法:运用FMEA识别自动口服摆药机调剂过程中的失效模式,分析其出现的原因,制定降低调剂差错的措施。结果:实施风险控制措施后,影响自动口服摆药机调剂差错风险失效模式的风险优先指数(risk priority number,RPN)值由119分降到55分,差异具有统计学意义(P<0.05)。结论:FMEA应用于自动口服摆药机调剂差错的风险管理,可有效降低调剂差错,提高药学服务质量。 相似文献
998.
999.
目的 基于分子网络研究四逆散治疗抑郁症的潜在生物学机制。方法 借助于中药系统药理学数据库和分析平台(TCMSP)数据库筛选四逆散的活性成分,筛选条件为口服利用率、药物相似性和血脑屏障透过率,并挖掘四逆散活性成分靶点和抑郁症的治疗靶点。利用韦恩图找到活性成分靶点和疾病靶点的交集靶点,对应相应成分定义为四逆散抗抑郁的有效成分。利用String在线数据库进行交集靶点蛋白质-蛋白质相互作用网络的预测,并利用DAVID数据库进行交集靶点KEGG信号通路的富集分析。最后使用Cytoscape 3.6软件进行活性成分-靶点网络及有效成分-靶点-信号通路的构建和拓扑分析。结果 筛选出了四逆散107个有效成分和28个重要的抗抑郁症靶点。四逆散抗抑郁症的重要靶点显著富集于神经活性配体-受体相互作用、5-羟色胺能突触、多巴胺能突触、逆行内源性大麻素信号传导、钙信号通路等10个信号通路中。结论 本研究从分子网络的角度初步揭示了四逆散治疗抑郁症的潜在作用机制,其主要的生物学机制可能与以神经活性配体-受体相互作用为中心的信号通路有关。 相似文献
1000.
Chunmei Guo MD Qionggui Zhou MD Dongdong Zhang PhD Pei Qin PhD Quanman Li MD Gang Tian MD Dechen Liu PhD Xu Chen MD Leilei Liu PhD Feiyan Liu PhD Cheng Cheng PhD Ranran Qie MD Minghui Han MD Shengbing Huang MD Xiaoyan Wu MD Yang Zhao PhD Yongcheng Ren PhD Ming Zhang PhD Yu Liu PhD Dongsheng Hu PhD 《Diabetes, obesity & metabolism》2020,22(1):79-90