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1.
目的探讨环氧合酶2(cyclooxygenase-2,COX-2)和血管内皮生长因子(vascularendothelial growthfactor,VEGF)在人胃癌组织中表达及其相关性。方法应用免疫组织化学SABC法检测53例人胃癌组织中COX-2、VEGF和CD34的表达,并以40例正常胃粘膜标本作为对照。对CD34阳性血管进行微血管密度(microvesseldensity,MVD)计数。对COX-2和VEGF的表达采用半定量计分法判定,并结合临床资料进行统计学分析。结果53例人胃癌组织中,COX-2表达阳性者44例,阳性率为83.0%;VEGF表达阳性者45例,阳性率为84.9%。COX-2表达与VEGF表达相关显著(P<0.05)。并且,COX-2和VEGF的表达与TNM分期(P<0.05,P<0.05)、淋巴结转移(P<0.01,P<0.05)和远处转移(P<0.01,P<0.05)相关。COX-2/VEGF同高表达组中MVD值(79.5±25.8)高于COX-2/VEGF同低表达组中的MVD值(45.0±13.9),差异非常显著(P<0.01)。结论胃癌组织中COX-2与VEGF共表达,并相互协同促进肿瘤血管生成和转移。  相似文献   
2.
A maternity testing case is reported, in which the child showed tri-allelic patterns in two short tandem repeat (STR) loci. The genotypes of Penta D of the mother and the child were 9,13 and 9,10,13, respectively. Those of D21S11 were 32.2,35 and 29,35, respectively, but intensity ratio of alleles 29 and 35 of the child was 1:2. These results suggested the copy number variations (CNVs) or trisomy of chromosome 21. By further examination using STR-based chromosome aneuploidy detection kit, three alleles were detected in D21S1411, LFG21 and Penta D, and 2 alleles with intensity ratio of 1:2 were observed in D21S2502, D21S1435, D21S11 and D21S1246. Karyotype and whole-genome SNP array analyses showed that the child had a free trisomy 21. In addition, partially homologous non-sister chromatid crossover occurred at the region 19181770-39499178 on the long arm of chromosome 21.  相似文献   
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Tuberculosis     
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4.
目的针对目前模拟人体的泌尿系统模型结构单一、用途局限、不适于体外模拟实验等不足,本文将计算机辅助设计及制作(CAD/CAM)等技术应用于医学模拟模型的开发,设计制作了带双层管壁结构的多用途透明泌尿系统模型。方法利用现有的人体泌尿系统解剖参数,基于UGNX软件完成模型的设计,然后利用MasterCAM软件对模型进行数控编程,通过数字控制车床对模型各部件进行加工,最后组装各部件完成制作。结果完成带双层管壁结构的透明泌尿系统模型的制作,该模型具有功能多、成本低廉、模拟程度高等优点。结论该模型的制作是医工结合的一个新的尝试。  相似文献   
5.
目的描述和分析BMI、腰围、腰臀比、腰高比、小腿围、腰围小腿围比值(WCR)、脂质蓄积指数(LAP)、内脏脂肪指数(VAI)、中国内脏脂肪指数(CVAI)、身体形态指数、中国身体形态指数(CABSI)和身体圆度指数与海南百岁老人全因死亡间的关联。方法整群抽样方法抽取的海南百岁老人共1 002人。随访时间的M(Q1, Q3)为4.16(1.31, 5.04)年, 结局为全因死亡, 使用Cox比例风险回归分析各肥胖相关身体测量指标与全因死亡的关联, 并使用受试者工作特征曲线曲线下面积(AUC)进行比较。结果总人群中小腿围对全因死亡的判定能力最强, AUC为0.61(95%CI:0.57~0.64), 分性别结果与总人群一致(P<0.05)。WCR次之(AUC为0.58), 再次是BMI、LAP和腰围, AUC分别为0.55、0.55和0.54, 而CABSI、腰臀比和VAI的判定能力较弱, AUC分别为0.51、0.50和0.50。结论本研究比较了12项肥胖相关指标与海南百岁老人全因死亡间的关联, 发现小腿围的预测判定能力最好, 且呈剂量反应关系, 提示可作为长寿老人死亡风险预测的参...  相似文献   
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7.
Background and aimsPremature cardiovascular disease cause excess mortality in type 1 diabetes (T1D). The Steno T1D Risk Engine was developed and validated in northern European countries but its validity in other populations is unknown. We evaluated the performance of the Steno T1D Risk Engine in Italian patients with T1D.Materials and methodsWe included patients with T1D with a baseline visit between July 2013 and April 2014, who were free of cardiovascular disease and had complete information to estimate risk. The estimated cardiovascular risk score was compared with the 5-year rate of cardiovascular events by means of logistic regression.ResultsAmong 223 patients (mean age 43 ± 13 years, 34.5% male, mean duration of diabetes 22 ± 12 years) the mean estimated cardiovascular risk at 5 years was 5.9% (95% C.I. 5.2–6.5%). At baseline, high estimated risk discriminated the presence of asymptomatic atherosclerosis better than microangiopathy, and was not associated with markers of inflammation or endothelial activation. After a mean follow-up of 4.7 ± 0.5 years, only 3 cardiovascular events were observed and nonetheless the risk score was significantly associated with their incidence (OR 1.22; 95% C.I. 1.08–1.39, p = 0.001). However, the observed event rate was significantly lower than the estimated one (3 vs 13; 95% C.I. 12–14; p < 0.001).ConclusionThe Steno T1D Risk Score identified subjects with subclinical atherosclerosis and high cardiovascular risk in an Italian T1D population. However, the absolute risk was significantly overestimated. Further studies in larger population are needed to confirm these results.  相似文献   
8.
《Archives of oral biology》2014,59(6):654-661
ObjectivesMast cells (MCs) are implicated in the pathogenesis of allergic reactions and inflammatory conditions through the release of inflammatory mediators. So far limited attention has been given to the role of MCs in periodontitis. T cell immunoglobulin mucin domain (TIM)-3 is an immunomodulatory molecule and influences MC function. However, whether TIM-3 is expressed on MCs in the process of human periodontal disease has not been reported. Therefore, we identified MCs by toluidine blue staining and examined the expression of TIM-3 on tryptase-positive MCs in different severities of human chronic periodontitis using double-immunofluorescence staining in this study.Material and methodsA total of 83 human periodontal specimens were involved in this study, including healthy control tissues (n = 25), chronic moderate periodontitis (n = 28), and chronic severe periodontitis (n = 30). The gingival specimens were fixed in 10% buffered formalin, stained with haematoxylin and eosin for histopathology, with toluidine blue for MCs, and with double-immunofluorescence for identification of tryptase-TIM-3 double-positive MCs in gingival tissues.ResultsCompared with healthy controls, the score of gingival tissue inflammation was significantly increased in the chronic moderate periodontitis (P = 0.013) and chronic severe periodontitis (P < 0.0001), and the densities (cells/mm2) of tryptase-TIM-3 double-positive MCs were significantly increased in both the chronic moderate (P = 0.011) and severe periodontitis groups (P < 0.0001). However, compared with the chronic moderate periodontitis group, both the score of gingival tissue inflammation (P = 0.012) and the density of tryptase-TIM-3 double-positive MCs (P = 0.011) in gingival tissue were significantly increased in the severe periodontitis groups.ConclusionSignificantly increased number of tryptase-TIM-3 double-positive MCs had the similar tendency as the severity of periodontitis inflammation in human chronic periodontitis. Our data suggest that TIM-3 may have a role on MCs in human chronic periodontitis.  相似文献   
9.
目的 观察编码屋尘螨主要过敏原Der p1和Der p2的质粒DNA疫苗对哮喘小鼠脾细胞Foxp3 调节性T细胞(regulatory T cells,Treg细胞)功能的影响.方法 以屋尘螨提取液复制哮喘模型后,将编码Der p1、Der p2的真核表达质粒pDs-Der p1、pCI-neo-Der p2等量混合接种小鼠后对小鼠进行再次激发.分离小鼠脾脏细胞,以流式细胞仪方法检测CD4 CD25 Foxp3 Treg细胞比例.采用磁珠法分离CD4 CD25 T细胞,流式细胞仪检测其Foxp3基因的表达,并以IL-2进行刺激观察其增殖反应,测定其上清液中的IL-10、TGF-β含量.将分离的Treg细胞与哮喘小鼠CD4 CD25-T细胞共同培养,观察Treg细胞对CD4 CD25-T细胞增殖及IL-4、IL-5、IFN-γ的影响.结果 哮喘组小鼠脾脏CD4 CD25 Foxp3 Treg细胞比例显著低于对照组,经DNA疫苗治疗后CD4 CD25 Foxp3 Treg细胞显著增加.体外培养发现各组CD4 CD25 Foxp3 Treg细胞增殖能力均显著低于CD4 CD25-T细胞,培养液上清中均未检测到IL-10和TGF-β存在.3组CD4 CD25 Foxp3 Treg细胞均可显著抑制哮喘CD4 CD25-T细胞的增殖及IL-4、IL-5和IFN-γ的分泌,但在3组Treg细胞中,哮喘组Treg细胞作用显著低于其他两组.结论 Treg细胞可显著抑制哮喘CD4 CD25-T细胞的增殖及炎性介质的分泌,哮喘小鼠不仅出现CD4 CD25 Foxp3 Treg细胞数量的减少,而且其功能也可能出现缺陷.DNA疫苗治疗可以诱导CD4 CD25 Foxp3 Treg细胞增加,并恢复其功能活性.  相似文献   
10.
目的:探讨人宫颈癌Hela细胞株经顺铂(DDP)作用后其超弱发光与细胞增殖活性变化的关系.方法:选择DDP诱导人宫颈癌Hela细胞株,比较人宫颈癌Hela,Hela+DDP细胞株形态变化.MTT比色法、流式细胞仪检测细胞生长周期变化及凋亡情况;用IFFM-D型流动式化学发光仪检测Hela,Hela+DDP细胞的超弱发光强度变化.结果:DDP对Hela细胞有生长抑制作用,并呈时间和浓度依赖性,其48h的Ic5。值为3mg,/L,当DDP浓度在3mg/L以下时,对Hela细胞无明显毒性作用,超过此浓度时,其毒性呈剂量效应关系(P〈0.01).流式细胞仪结果表明,与Hela细胞相比较,Hela+DDP细胞G2期细胞数增多,而G1,S期的细胞数明显减少(P〈0.01);细胞凋亡率在24,48,72h分别为(11.4±5.8)%,(21.8±7.9)%,32.5±11.6)%.在1×10^-4mol/L鲁米诺及3mL/L双氧水(H2O2)条件下超弱发光强度随着时间的变化,Hela+DDP细胞明显降低(P〈0.01).结论:在DDP非毒性剂量作用后,Hela+DDP细胞超弱发光强度降低,提示超弱发光检测可能作为筛选敏感化疗药物的一项指标.  相似文献   
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