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BackgroundPatients' inflammatory history is an important factor underlying red blood cell (RBC) alloimmunization, which is a frequent transfusion complication among individuals with sickle cell disease (SCD). HLA-G has been associated with different inflammatory and auto - immune diseases. Our goal was to verify whether the HLA-G + 3142 C>G and 14-bp Ins/Del variations are associated with RBC antibody development among SCD patients.MethodsThis was a single-center case-control study. SCD patients were randomly selected for the study and divided into two groups: ‘Alloimmunized’ and ‘Nonalloimmunized’ depending on the presence of irregular antibodies. The ‘Alloimmunized’group was further divided into two subgroups according to the presence of only antibodies against the Rh and Kell blood group systems or the existence of antibodies to antigens of the other blood group systems.ResultsA total of 213 patients were included in the study (110 alloimmunized and 103 non-alloimmunized). The ‘Alloimmunized’ and ‘Non-alloimmunized’ groups did not differ statistically regarding the HLA-G + 14 bp Ins/Del ( p = 0.494) and + 3142 C>G ( p = 0.334). Individuals who had only antibodies against the Rh and Kell antigens had a frequency of HLA-G + 3142GG genotype almost twice as high compared to the groupwith antibodies against less immunogenic antigens ( p = 0.043).ConclusionsThe genotype frequency of HLA-G + 3142 C>G differs among alloimmunized SCD patients, depending on the presence of antibodies against low immunogenic RBC antigens. This highlights a possible role played by the HLA-G molecule in the RBC alloimmunization process.  相似文献   
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BackgroundTo accurately identify ABO blood typing in pre-transfusion testing is very important to ensure blood transfusion safely, which is a major responsibility of blood station.MethodsEighty-one blood donors samples with ABO blood group typing discrepancy was collected among 61952 donor samples in our blood station from January 2019 to July 2020. Blood group serological method was used to detect ABO blood group. DNA Sequencing was used to determine the genotype. The antibody screening test detects antibodies other than ABO.ResultsIn total, 61,952 donor samples were analysed for ABO typing discrepancies. The incidence among blood donors was 0.13% (81/61952). The most common reason of ABO typing discrepancies was due to specific antibody or non-specific agglutination (54.32%, 44/81), mainly anti-M antibody, cold autoantibody, anti-D antibody, anti-N antibody and anti-Lea antibody. The major cause of forward typing discrepancies among blood donors was ABO subgroups (25.93%, 21/81), including 10 cases of A subtype (1 case of A2, 2 cases of A3, 2 cases of Ax, 3 cases of AxB, 1 case of Ael, 1 case of Ahm), 6 cases of B subtype (2 cases of B3, 1 case of Bel, 3 cases of AB3), 2 cases of B subtype (A), 1 case of cisAB, and 2 cases of acquired B. The serum antibody was weakened in 16 cases (19.75%).ConclusionsThe blood types should be correctly identified by combining serology with gene sequencing to ensure the safety of clinical blood transfusion, when the forward and reverse typing discrepancies among the blood donors.  相似文献   
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背景:原发性线粒体病具有高度的临床和遗传异质性,其中周围神经是线粒体病的常见受累器官之一。 目的:总结COX20基因变异相关周围神经病的临床表型及遗传学特征。 设计:病例系列报告。 方法:回顾性收集2018年5月至2020年5月复旦大学附属儿科医院诊治的COX20基因变异相关周围神经病患儿的临床资料,总结其临床表现、基因检测结果及治疗效果,并以“COX20”、“线粒体复合物Ⅳ缺乏症(Complex Ⅳ deficiency)”为关键词检索中英文数据库。检索时间均为从建库至2021年12月。总结已报道COX20基因变异与临床表型的关系。 主要结局指标:临床表型和COX20基因变异位点。 结果:4例患儿纳入分析,男、女各2例,其中3例自幼运动发育落后。4例均在儿童期起病,均以行走不稳为首发症状。肌电图均提示多发性周围神经损害改变,感觉神经轴索受累为主。4例患儿均携带COX20基因复合杂合变异,包括错义变异2个,无义变异和移码变异各1个,其中移码变异c.262delG(p.E88Kfs*35)尚未见报道。文献复习目前共报道COX基因变异18个家系22例患儿(包括本文病例),起病中位年龄为5(1.0~17)岁,22例均以行走困难或步态不稳起病,11例(50.0%)有精神运动发育迟滞,病程中14例(63.6%)出现构音障碍,14例(63.6%)出现肌力下降和/或足部畸形,8例(36.4%)出现共济失调,6例(27.3%)出现肌张力障碍,5例(22.7%)存在认知倒退等。21例患儿行神经传导及肌电图检查,19例(90.5%)提示多发性周围神经病变。头颅(18例)及脊髓(10例)MR检查提示,脊髓萎缩4例(40%),小脑萎缩4例(22.2%)。9例患儿已无法独立行走,丧失独立行走能力中位年龄为10(7~21)岁。目前共报道9个变异位点,4种变异类型,其中错义变异5个,剪切变异2个,无义变异和移码变异各1个。 结论:COX20基因变异患者多早期起病,以周围神经系统病变为主要表现,可合并构音障碍、共济失调、肌张力障碍、认知倒退等,病情逐渐进展,致残率高。COX20基因变异类型以错义变异最常见。  相似文献   
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《Vaccine》2022,40(2):255-265
The high mutation rate of infectious bronchitis virus (IBV) poses a significant threat to the protective efficacy of vaccines. This study aimed at analyzing the S1 genes of IBV field strains isolated in Southwestern China from 2018 to 2020, assessing the pathogenicity of four dominating strains, and evaluating the protective efficacy of four commercial vaccine strains against the endemic representative strains. Thirty-two field strains of IBV were isolated in Southwestern China from 2018 to 2020. Phylogenetic analysis of their S1 genes revealed the nucleotide homology ranged from 64.6% to 100%, and belonged to five genotypes [GI-19 (QX, 53.13%), GI-28 (LDT3-A,15.63%), GI-7 (TW, 12.50%), GI-1 (Mass, 6.23%), GVI-1 (TC07-2, 6.25%)], and two variant groups [variant-3 (3.13%) and variant-5 (3.13%)]. Recombination events between field and vaccine strains or between field strains were identified in the S1 genes of eight IBV field strains. The CK/CH/YNKM/191128 and CK/CH/CQBS/191203 strains of GI-19 showed morbidity rates of 66.7% and 73.7%, respectively, and mortality rates of 13.3% and 33.3%, respectively. Besides, the CK/CH/SCYC/191030 and CK/CH/GZGY/191021 strains of GI-28 caused morbidity rates of 60% and 86.7%, respectively, and mortality rates of 33.3%. The protective efficacy of the four commercial live vaccine strains (4/91, FNO-E55, LDT3-A, and QXL87) ranged from 70% ? 100% and reduced tissue lesions against CK/CH/GZGY/191021 and CK/CH/CQBS/191203 strains. LDT3-A strain was the most effective one but still could not completely prohibit IBV shedding. These findings provide a reference for IBV molecular evolution analysis and control of IB.  相似文献   
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BackgroundDaclatasvir (DCV) is an approved NS5A inhibitor with potent anti-HCV activity and broad genotype coverage. DCV resistance-associated variants (RAVs) have been described for patients infected with genotype (GT) 1, but increased GT4 prevalence in European countries as a result of immigration has boosted interest in this genotype.ObjectivesEstablishment of NS5A variability in treatment-naive patients with HCV genotype 4 infection and a case study of the dynamics of resistance-associated variants in a virologic failure receiving pIFN/RBV + DCV, as assessed by ultra-deep sequencing.Study designFive treatment-naïve GT4 patients (GT4a [n = 1], GT4d [n = 3], GT4o [n = 1]) were evaluated for inclusion in the COMMAND-4 study and treatment with pIFN/RBV ± DCV.ResultsPatient (Pt) 1 received pIFN/RBV; Pts2–4 received pIFN/RBV + DCV; Pt5 was a screening failure. Pt1 relapsed; Pt2 experienced breakthrough at Wk4; Pts3 and 4 achieved a sustained virologic response. No substitutions associated with DCV-resistance were detected at baseline. In terms of viremic time points for Pts1 and 2, the extent of NS5A diversity pre-treatment was not significantly related to viral load (r = −0568; p = 0.035). In Pt2, multiple substitutions associated with DCV-resistance were observed after breakthrough at NS5A amino acid positions 28, 31 and 93. These substitutions were frequently observed on the same haplotype (L28S + M31I = 55.52, 82.50, and 99.36% at Wk4, 8 and 9; L28S + M31I + Y93H = 11.77, 5.01 and <0.6% at Wk4, 8 and 9).ConclusionsThis is the first report to describe DCV-resistance in patients infected with GT4d, supporting a possible role for a recently described RAV (L28S), and presenting the dynamics of HCV quasispecies during therapy failure, with indications of changes of diversity and association of mutations.  相似文献   
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The current epidemic of Hepatitis C infection in HIV-positive men who have sex with men is associated with increasing use of recreational drugs. Multiple HCV infections have been reported in haemophiliacs and intravenous drug users. Using ultra-deep sequencing analysis, we present the case of an HIV-positive MSM with evidence of three sequential HCV infections, each occurring during the acute phase of the preceding infection, following risk exposures. We observed rapid replacement of the original strain by the incoming genotype at subsequent time points. The impact of HCV super-infection remains unclear and UDS may provide new insights.  相似文献   
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《Vaccine》2016,34(33):3862-3866
The objective of the present study was to assess safety and efficacy of a new modified live-virus porcine reproductive and respiratory syndrome (PRRS) genotype 1 vaccine in pregnant sows at various stages of gestation under field conditions. A total of 505 sows and gilts were allocated to two treatment groups and maintained in separate facilities. Animals of group 1 were vaccinated with a commercial modified live genotype 1 PRRSV vaccine (control product, CP), while animals of group 2 were immunized with a new modified live genotype 1 PRRSV vaccine (investigational veterinary product, IVP) (ReproCyc® PRRS EU, Boehringer Ingelheim Vetmedica GmbH). Injection site reactions were noted to be significantly less frequent in the IVP group compared to the CP group for pain (p = 0.039), redness (p = 0.030), heat (p = 0.016) and swelling (p = 0.002). The mean total number of piglets alive at weaning did not differ significantly between both study groups (10.6 vs. 11.0, p = 0.375). However, pre-weaning mortality was significantly higher (p = 0.005) in piglets from the CP group (14.1% vs. 10.9%). Analyses of reproductive performance data for both groups did not result in statistically significant differences between CP group and IVP group for number of piglets alive (12.7 and 12.6, respectively), healthy live (11.9 and 11.8), weak (0.7 and 0.5), stillborn (1.0 and 0.8) and mummified piglets (0.3 and 0.2) per litter. No differences were detected between both groups for piglet birth weights, while body weights at weaning (7.2 kg vs. 6.6 kg, p = 0.026) and average daily gain (0.2445 kg vs. 0.2211 kg, p = 0.037) were significantly higher in piglets from the IVP group. In conclusion, the administration of a single dose of ReproCyc® PRRS EU to sows and gilts at various stages of gestation confirmed non-inferiority to a commercial PRRS vaccine regarding safety and efficacy parameters under field conditions.  相似文献   
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