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991.
The aim of this study was to determine whether double labelling of human umbilical cord mesenchymal stem cells (hUCMSCs) with gadolinium‐diethylene triamine penta‐acetic acid (Gd‐DTPA) and PKH26 influences their biological characteristics. A tissue adherence technique was used to separate and purify the hUCMSCs and flow cytometry was performed to detect the surface markers expressed on them. Gd‐DTPA and PKH26 were used to label the stem cells and MRI and fluorescence microscopy were used to detect the double‐labelled hUCMSCs. A MTT assay was used to delineate the growth curve. Transmission electron microscopy (TEM) and atomic force microscopy were used to demonstrate the ultrastructural features of the hUCMSCs. Flow cytometry showed that hUCMSCs highly expressed CD29, CD90, CD44 and CD105. No expression of CD31, CD34 and CD45 was detected. Very low expression of HLA‐DR and CD40 was detected. Atomic force microscopy showed these cells were long, spindle shaped, and the cytoplasm and nucleus had clear boundaries. After double labelling, TEM showed Gd particles aggregated in the cytoplasm in a cluster pattern. The proliferation activity, cell cycle, apoptosis and differentiation of the stem cells were not influenced by double labelling. Thus a tissue adherence technique is helpful to separate and purify hUCMSCs effectively; and Gd‐DTPA and PKH26 are promising tracers in the investigation of migration and distribution of hUCMSCs in vivo.  相似文献   
992.
目的探讨apyrase(三磷酸腺苷二磷酸水解酶)对过敏性哮喘小鼠气道炎症及气道重塑的作用。方法采用C57BL/6雌性小鼠建立鸡卵清蛋白(OVA)致敏和激发的过敏性哮喘模型,并给予apyrase处理;以非致敏的同背景雌性小鼠作为对照。于最后1次激发24~48 h,完成小鼠气道高反应性测定、支气管肺泡灌洗及取肺组织。病理学方法评价肺组织气道炎症、杯状细胞及气道重塑,瑞氏吉姆莎染色并计数灌洗液的分类细胞,酶联免疫吸附法测定灌洗液细胞因子,实时定量PCR法测定肺组织转录因子(GATA3)水平。结果 Apyrase减轻哮喘小鼠肺组织嗜酸性粒细胞炎症,降低气道炎性细胞、Th2相关细胞因子及肺组织GATA3核酸水平;减轻气道上皮杯状细胞增生及胶原沉积。结论 Apyrase可减轻小鼠过敏性哮喘的气道炎症及气道重塑。  相似文献   
993.
目的:探讨高原外训军人心理健康、认知因素与急性高山病的相关性。方法:采用基本信息问卷、Lake Louise急性高山病评分量表(AMS)、症状自评量表(SCL-90)、焦虑自评量表(SAS)和抑郁自评量表(SDS)对191名急进高原进行高原适应性训练的军人施以团体测验。结果:研究样本SCL-90的躯体化因子显著高于全国正常成人常模(t=5.019,P0.001)。AMS症状阳性组与阴性两组样本在文化程度(t=2.385,P0.05)、社会支持中的倾诉方式(t=2.542,P0.05)、求助方式(t=2.133,P0.05)、对AMS的认知(t=2.423,P0.05)、SCL-90总分(t=-4.936,P0.001)及各因子分均有显著差异。SCL-90总分、对AMS应对策略的认知对预测AMS症状总分有一定的预测作用。结论:高原外训军人心理健康水平、认知因素对AMS有显著的影响,运用合理的心理干预技术,可降低AMS的发生率,增强高原作战部队的战斗力。  相似文献   
994.
995.
We conducted this study to investigate the synergistic effect of human urine-derived stem cells (USCs) and surface modified composite scaffold for bladder reconstruction in a rat model. The composite scaffold (Polycaprolactone/Pluronic F127/3 wt% bladder submucosa matrix) was fabricated using an immersion precipitation method, and heparin was immobilized on the surface via covalent conjugation. Basic fibroblast growth factor (bFGF) was loaded onto the heparin-immobilized scaffold by a simple dipping method. In maximal bladder capacity and compliance analysis at 8 weeks post operation, the USCs-scaffoldheparin-bFGF group showed significant functional improvement (2.34 ± 0.25 mL and 55.09 ± 11.81 µL/cm H2O) compared to the other groups (2.60 ± 0.23 mL and 56.14 ± 9.00 µL/cm H2O for the control group, 1.46 ± 0.18 mL and 34.27 ± 4.42 µL/cm H2O for the partial cystectomy group, 1.76 ± 0.22 mL and 35.62 ± 6.69 µL/cm H2O for the scaffold group, and 1.92 ± 0.29 mL and 40.74 ± 7.88 µL/cm H2O for the scaffoldheparin-bFGF group, respectively). In histological and immunohistochemical analysis, the USC-scaffoldheparin-bFGF group showed pronounced, well-differentiated, and organized smooth muscle bundle formation, a multi-layered and pan-cytokeratin-positive urothelium, and high condensation of submucosal area. The USCs seeded scaffoldheparin-bFGF exhibits significantly increased bladder capacity, compliance, regeneration of smooth muscle tissue, multi-layered urothelium, and condensed submucosa layers at the in vivo study.  相似文献   
996.
An inherited predisposition to acute myeloid leukaemia (AML) is exceedingly rare, but the investigation of these families will aid in the delineation of the underlying mechanisms of the more common, sporadic cases. Three AML predisposition genes, RUNX1, CEBPA and GATA2, have been recognised, but the culprit genes in the majority of AML pedigrees remain obscure. We applied a combined strategy of linkage analysis and next-generation sequencing (NGS) technology in an autosomal-dominant AML Chinese family with 11 cases in four generations. A genome-wide linkage scan using a 500K SNP genotyping array was conducted to identify a previously unreported candidate region on 20p13 with a maximum multipoint heterogeneity LOD (HLOD) score of 3.56 (P=0.00005). Targeted NGS within this region and whole-exome sequencing (WES) revealed a missense mutation in TGM6 (RefSeq, NM_198994.2:c.1550T>G, p.(L517W)), which cosegregated with the phenotype in this family, and was absent in 530 healthy controls. The mutated amino acid was located in a highly conserved position, which may be deleterious and affect the activation of TGM6. Our results strongly support the candidacy of TGM6 as a novel familial AML-associated gene.  相似文献   
997.
四川省西部系高山高原地带,从未发现过肺吸虫病(并殖吸虫病)患者及其中间宿主。本病主要流行于东部的四川盆地,据80个县(市)的调查,流行区遍布于盆地的各个方位。病原的第一中间宿主主要为拟钉螺,第二中间宿主主要有锯齿华溪蟹等18种淡水蟹(包括新发现6个新种及新亚种)。已发现豹猫和果子狸有自然感染,系野生动物保虫宿主。  相似文献   
998.
Chen H  Liu J  Luo L  Zirkin BR 《Endocrinology》2004,145(10):4441-4446
The wealth of knowledge about the function and regulation of adult Leydig cells, the cells within the mammalian testis that produce testosterone, make these cells ideal for studying principles and mechanisms of aging. A hallmark of mammalian aging is decreased serum testosterone concentration. In the Brown Norway rat, this has been shown to be associated with the reduced ability of aged Leydig cells to produce testosterone in response to LH. Herein, we demonstrate that culturing the aged cells with dibutyryl cAMP, a membrane-permeable cAMP agonist that bypasses the LH receptor-adenlyly cyclase cascade, restores testosterone production to levels comparable to those of young cells and also restores steroidogenic acute regulatory protein and P450scc, the proteins involved in the rate-limiting steps of steroidogenesis. These results strongly suggest that signal transduction deficits are responsible for reduced steroidogenesis by aged Leydig cells and that bypassing signal transduction reverses the steroidogenic decline by the aged cells.  相似文献   
999.
We aimed to assess the impact of size mismatching between grafts and recipients on outcomes of infants or small children after LDLT. Between October 2006 and December 2014, 129 LDLT recipients weighing no more than 8 kg were retrospectively analyzed. The entire cohort was categorized into three groups by GRWR: GRWR<3.0% (group A, n = 38), 3.0%≤GRWR<4.0% (group B, n = 61), and GRWR≥4.0% (group C, n = 30). Baseline characteristics were similar among groups A, B, and C. Compared with groups A and B, post‐transplant alanine aminotransferase and aspartate aminotransferase within seven days were significantly higher in group C; however, differences between total bilirubin and albumin after transplantation were not prominent. Moreover, incidences of surgical complications, perioperative deaths, infections, and acute rejections were all comparable among the three groups. Five‐yr patient survival rates for groups A, B, and C were 89.5%, 88.9%, and 81.6%, respectively (p = 0.872), and the graft survival rates were 89.5%, 86.6%, and 81.6%, respectively (p = 0.846). In conclusion, GRWR between 1.9% and 5.8% would not cause noticeable adverse events for infantile LDLT recipients ≤8 kg. However, there is still a role for considering reduction in the graft mass as an applicable strategy in selected cases.  相似文献   
1000.
Relationship between metabolic enzyme polymorphism and colorectal cancer   总被引:8,自引:0,他引:8  
AIM: To clarify the influence of genetic polymorphisms on colorectal cancer. METHODS: The results of 42 related studies from 1990 to 2001 were analyzed by meta-analysis. Mantel-Haenzel fixed-effect model or Dersimonian-Laird random-effect model and ReviewManager 4.1 statistical program were applied in processing the data. RESULTS: Meta analysis of these studies showed that GSTT1 deletion (pooled OR= 1.42), N-acetyltransferase 2 (NAT2)-rapid acetylator phenotype and genotye (pooled OR = 1.08) and NAT2-rapid acetylator phenotype (pooled OR = 1.15) had a significantly increased risk for colorectal cancer (P<0.05), other genotypes like GSTM1 deletion, GSTP1 1le105Val, NAT1*10, NAT2-rapid acetylator genotype CYP1A1 Lle462Val, CYP1A1 MspI*C, MTHFR C677T and MTR A2759G had no significant relationship with colorectal cancer (P>0.05). CONCLUSION: Risks for colorectal cancer are significantly associated with the genetic polymorphisms of GSTT1 deletion, NAT2-rapid acetylator phenotype and genotye and NAT2-rapid acetylator phenotype.  相似文献   
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