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目的: 探讨骨髓间质干细胞(MSCs)吲哚胺2,3-双加氧酶(IDO)活性对抑制T淋巴细胞应答反应的影响。方法: 从人骨髓中分离培养间质干细胞,通过其形态特点、表面标志及多向分化能力检测进行鉴定。以浓度为2×105 U/L的 IFN-γ对分离的MSCs诱导18 h,检测MSCs上IDO mRNA和IDO蛋白表达。将经过IFN-γ 2×105 U/L诱导的MSCs预先接种在培养板中,再建立混合淋巴细胞培养(MLR)体系,利用MTT法检测T淋巴细胞增殖率,并用反相高效液相色谱法检测IDO活性。结果: IFN-γ能诱导MSCs上IDO mRNA和IDO蛋白的表达;MSCs的IDO活性抑制MLR体系中T淋巴细胞增殖率。结论: 经IFN-γ刺激后的MSCs在体外可抑制异体T淋巴细胞的免疫应答,IDO活性参与了这种免疫抑制作用的发挥。 相似文献
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《European journal of medical genetics》2021,64(12):104369
Genetic screening of Congenital Adrenal Hyperplasia (CAH) is known to be challenging due to the complexities in CYP21A2 genotyping and has not been the first-tier diagnostic tool in routine clinical practice. Also, with the advent of massive parallel sequencing technology, there is a need for investigating its utility in screening extended panel of genes implicated in CAH. In this study, we have established and utilized an Allele-Specific Polymerase Chain Reaction (ASPCR) based approach for screening eight common mutations in CYP21A2 gene followed by targeted Next Generation Sequencing (NGS) of CYP21A2, CYP11B1, CYP17A1, POR, and CYP19A1 genes in 72 clinically diagnosed CAH subjects from India. Through these investigations, 88.7% of the subjects with 21 hydroxylase deficiency were positive for eight CYP21A2 mutations with ASPCR. The targeted NGS assay was sensitive to pick up all the mutations identified by ASPCR. Utilizing NGS in subjects negative for ASPCR, five study subjects were homozygous positive for other CYP21A2 variants: one with a novel c.1274G>T, three with c.1451G>C and one with c.143A>G variant. One subject was compound heterozygous for c.955C>T and c.1042G>A variants identified using ASPCR and NGS. One subject suspected for a Simple Virilizing (SV) 21 hydroxylase deficiency was positive for a CYP19A1:c.1142A>T variant. CYP11B1 variants (c.1201-1G>A, c.1200+1del, c.412C>T, c.1024C>T, c.1012dup, c.623G>A) were identified in all six subjects suspected for 11 beta-hydroxylase deficiency. The overall mutation positivity was 97.2%. Our results suggest that ASPCR followed by targeted NGS is a cost-effective and comprehensive strategy for screening common CYP21A2 mutations and the CAH panel of genes in a clinical setting. 相似文献
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孤独症谱系障碍(ASD)是一组以不同临床表现为主要特征的神经发育性障碍。近年来,ASD儿童的发育倒退(DR)受到越来越多的关注,并被认为可能是ASD的一种特殊亚型。目前关于ASD儿童DR的影响因素尚不清楚,综合文献分析主要是由遗传、环境及其交互作用共同引起。本文拟从遗传和环境两方面对目前报道的ASD儿童DR影响因素进行总结,为该部分ASD患儿的临床早期识别和干预提供参考。 相似文献
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《Journal of renal nutrition》2022,32(6):744-750
PurposeTo investigate the effect of nutritional factors on bone mineral density (BMD) using quantitative computed tomography combined with blood biochemistry in patients on maintenance hemodialysis (MHD).MethodsSixty patients on MHD were divided into osteopenia (n = 20) and nonosteopenia (n = 40) groups. BMD, fat, and muscle mass were measured by quantitative computed tomography. The calcification of coronary artery and hilar lymph node and computed tomography attenuation values of the liver and spleen were also analyzed. Differences between the two groups were compared, and the risk factors for osteopenia were analyzed by logistic regression analysis.ResultsPatients in the osteopenia group had lower albumin levels than those in the nonosteopenia group (37.84 ± 3.00 vs 42.03 ± 4.05 g/L; P < .001). Logistic regression showed that patients with lower albumin levels had a higher risk of osteopenia (odds ratio, 1.462; 95% confidence interval, 1.313–1.801; P = .003). BMD was negatively correlated with fat mass (r = ?0.365, P = .004) and positively correlated with the ratio of muscle mass to fat mass (r = 0.431, P = .001). There was no significant difference in the rate of calcification of coronary artery or hilar lymph nodes between the two groups. Computed tomography values of the liver and spleen were positively correlated with the duration of dialysis (r = 0.55, P = .001; r = 0.42, P < .001, respectively).ConclusionLow albumin levels are associated with an increased risk of osteopenia in patients on MHD. Abdominal fat is a risk factor for reduction in BMD in MHD patients, and the ratio of abdominal muscle mass to fat mass is a protective factor for BMD. 相似文献
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【目的】 探索期刊集约化发展新模式,解决编务工作流程繁琐、工作量大、高强度、单调机械重复劳动等问题,实现编务工作整合。【方法】 采用实地参观、现场交谈及电话访问等方式对38种医药学期刊编务工作进行调研,结合编务工作中实际操作层面的共性问题,设计作者信息数据表和打印模板,利用Python编程推进编务工作的有效整合。【结果】 基于作者填写的信息数据批量生成对接期刊合作银行、编辑部财务、快递公司等部门的信息表单,并根据编务个性化需求实现邮寄信息表单的自动打印功能。【结论】 期刊编辑部工作整合应充分发挥信息化在期刊发展中的赋能作用,编务工作应最大限度地集成优势、统筹共性事务,以保证整个出版工作的有效开展。 相似文献
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