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701.
目的:分析犬自体肺组织瓣修补食管壁部分缺损的可行性。方法:实验于2003-01/2004-11在中国医科大学附属第二医院动物实验室完成。选用健康成年杂种犬20只,按随机数字表法分为2组,即支架组和无支架组,每组10只。20只实验犬经右胸第5肋间进胸,于胸内中段食管处胸内食管侧壁制成长4cm,环1/2~2/3周径全层缺损。于相应部位选择适当的肺组织,制成带蒂类舌状肺组织瓣。两组均将肺组织瓣覆盖并缝合固定于食管缺损处,支架组于食管缺损内衬自扩性记忆合金支架(管腔直径2.0cm、长6.0cm)并固定。术后抗炎及营养支持治疗。观察实验犬术后情况,并于术后2,4,6,8,10和12周定期处死实验犬行组织学观察。结果:无支架组实验犬存活7只,其中1只犬存活>24个月;支架组存活6只。①实验犬术后一般情况:存活犬于术后均能正常经口进食,早期有进食后呕吐,再吃下呕吐食物的现象,以支架组明显。②组织学观察结果:术后2周,无支架组均可见替代物表面有胶原及炎性渗出物,边缘见1~2层鳞状上皮细胞;支架组除有无支架组基本表现外,可见支架固定良好,光镜下见网架压迫处有较多中性粒细胞浸润。4~6周,两组均可见替代物表面有新生的3~5层复层鳞状上皮细胞;支架组见支架已基本陷入黏膜层内。8~10周,两组均可见管腔表面有6~8层新生复层鳞状上皮细胞;支架组网架边缘瘢痕组织增生,支架完全被包裹,炎症较重的局部有细胞爬行中断现象或新生细胞层数较薄,多为一两层。结论:应用自体肺组织瓣修补食管壁部分缺损是可行的,但支架组支架对食管修补处组织刺激大,炎性反应重,瘢痕重,因此如何选择合适的支撑物是今后替代节段性食管缺损面临的重要问题。 相似文献
702.
J de Wildt-Eggen; JG Schrijver ; HJ Bouter-Valk ; R Fijnheer ; M Bins ; HC van Prooijen 《Transfusion》1997,37(5):476-481
BACKGROUND : Storage of pooled platelet concentrates (PCs) with yields above 3.0 × 1011 platelets per unit in a 1-L PL-732 polyolefin container for 5 days often results in a drop in pH to below 6.0. Recently, new oxygen-permeable platelet containers (1-L PL-2410, 1-L and 1.5-L Compoflex) have been developed. The maximal platelet storage capacities of the new containers and the PL-732 were compared. STUDY DESIGN AND METHODS : Large platelet pools (n = 27) with platelet concentrations between 1.2 and 1.4 × 1011 per L were made from 3 to 5 PCs prepared from buffy coats. The pools were divided in equal volumes among the PL-732 and the three new platelet containers. Platelet counts in the PCs ranged from 1.0 to 5.0 × 1011 per unit. All PCs were stored on a flatbed shaker at 22 ± 2°C and evaluated on Days 1, 3, 5, and 7 by measuring platelet count, pH, pO2, pCO2, HCO3-, glucose, lactate, platelet swirling, and soluble p-selectin. RESULTS : Day 7 storage of PCs (n = 6) with yields between 3.0 and 4.0 × 1011 platelets in PL-732 showed mean ± SD pH values of 5.93 ± 0.05 and lactate values of 32.3 ± 7.9 mmol per L; in 4 of these 6 PCs, pH was below 6.0. In contrast, storage of these PCs in 1-L PL-2410 and 1.5-L Compoflex containers and of 2 of these 6 PCs in 1-L Compoflex containers showed pH values above 6.8. Lactate values were 15.5 ± 1.3, 15.3 ± 1.8, and 19.5 ± 4.7 mmol per L, respectively (p < 0.001 vs. PL-732). The platelet storage capacity of the new containers with platelet yields between 4.0 and 5.0 × 1011 per unit (n = 6) was evaluated. Day 7 storage of these PCs in the 1.5-L Compoflex showed an average pH value of 6.74 ± 0.20; in 2 of 6 PCs, pH was below 6.8. The average pH value in the PL-2410 was 6.38 ± 0.31, and in all PCs, pH was below 6.8. Average lactate values were 17.8 ± 5.7 and 25.8 ± 5.6 mmol per L (p < 0.05), respectively. Soluble p-selectin values on Day 7 of storage increased approximately twofold in all PCs. CONCLUSION : The new oxygen-permeable containers showed platelet quality comparable to that with the PL-732 and for longer storage periods and at higher platelet counts. 相似文献
703.
704.
Although the effects of vitamin E on platelet function have been investigated in vivo and in vitro, vitamin E quinone, a natural metabolite of vitamin E, has been virtually overlooked. This oxidized form of vitamin E inhibits platelet aggregation and secretion induced by various aggregating agents more effectively than vitamin E by a magnitude of 5-10-fold. Vitamin E and vitamin E quinone do not alter platelet ultrastructure or cellular concentrations of serotonin and adenine nucleotides, including cAMP. Inhibition of aggregation by vitamin E quinone occurs in the absence of detectable reduction of vitamin E quinone or oxidation of vitamin E and is readily reversed by washing the platelet. Only vitamin E quinone prevents arachidonic acid release and slightly inhibits cyclooxygenase, whereas both agents partially prevent calcium release from a platelet subcellular organelle. Vitamin E quinone also inhibited synthesis of prostacyclin by endothelial cells with basal synthesis in the presence of external arachidonic acid being less affected than thrombin-stimulated PGI2 production. The greater potency of vitamin E quinone in suppressing platelet function compared to vitamin E suggests that this quinone metabolite may be the better antithrombotic agent and possibly responsible for in vivo effects previously attributed to vitamin E. 相似文献
705.
706.
Barbara Wiedemann Edith Schober Thomas Waldhoer Julia Koehle Sarah E Flanagan Deborah JG Mackay Elisabeth Steichen Dagmar Meraner Lothar-Bernd Zimmerhackl rew T Hattersley Sian Ellard Sabine Hofer 《Pediatric diabetes》2010,11(1):18-23
Wiedemann B, Schober E, Waldhoer T, Koehle J, Flanagan SE, Mackay DJG, Steichen E, Meraner D, Zimmerhackl LB, Hattersley AT, Ellard S and Hofer S. Incidence of neonatal diabetes in Austria–calculation based on the Austrian Diabetes Register.
Background: Neonatal diabetes mellitus (NDM) is a rare monogenic form of diabetes which is diagnosed in the first 6 months of life. Several studies in the last few years provide information on genetic causes for NDM.
Objective: The aim of this study was to identify all patients with diabetes in the first 6 months of life through the Austrian Diabetes Register, which is available since 1989. A retrospective data analyses was performed to calculate the current incidence of NDM.
Subjects and Methods: Ten patients were registered with diabetes onset within the first 6 months of life in the Austrian Diabetes Register. Evaluation of detailed clinical data was performed by sending a questionnaire to all diabetes centers.
Results: Ten patients from nine different families with NDM were diagnosed in Austria from 1989 until September 2007. Seven patients (one male, six females) had transient NDM (TNDM), three (two males, one female) showed a permanent course [permanent neonatal diabetes mellitus (PNDM)]. One had immunodeficiency, polyendocrinopathy and enteropathy X-linked (IPEX) syndrome and another showed aplasia of the pancreas; no genetic etiology was found in the third case. In three out of seven patients with a transient course of NDM a genetic diagnosis was possible. Two female siblings had activating point mutations in the ABCC8 gene, although one patient had paternal uniparental isodisomy of chromosome 6q24. One patient's family did not consent to genetic testing.
Conclusions: The incidence of NDM in Austria is 1/160 949, with an incidence of 1/ 536 499 for PNDM and 1/229 928 for TNDM. 相似文献
Background: Neonatal diabetes mellitus (NDM) is a rare monogenic form of diabetes which is diagnosed in the first 6 months of life. Several studies in the last few years provide information on genetic causes for NDM.
Objective: The aim of this study was to identify all patients with diabetes in the first 6 months of life through the Austrian Diabetes Register, which is available since 1989. A retrospective data analyses was performed to calculate the current incidence of NDM.
Subjects and Methods: Ten patients were registered with diabetes onset within the first 6 months of life in the Austrian Diabetes Register. Evaluation of detailed clinical data was performed by sending a questionnaire to all diabetes centers.
Results: Ten patients from nine different families with NDM were diagnosed in Austria from 1989 until September 2007. Seven patients (one male, six females) had transient NDM (TNDM), three (two males, one female) showed a permanent course [permanent neonatal diabetes mellitus (PNDM)]. One had immunodeficiency, polyendocrinopathy and enteropathy X-linked (IPEX) syndrome and another showed aplasia of the pancreas; no genetic etiology was found in the third case. In three out of seven patients with a transient course of NDM a genetic diagnosis was possible. Two female siblings had activating point mutations in the ABCC8 gene, although one patient had paternal uniparental isodisomy of chromosome 6q24. One patient's family did not consent to genetic testing.
Conclusions: The incidence of NDM in Austria is 1/160 949, with an incidence of 1/ 536 499 for PNDM and 1/229 928 for TNDM. 相似文献
707.
目的:分析比较小分子干扰RNA和反义寡核苷酸技术的作用机制、作用靶点、设计方法和临床应用的异同。资料来源:应用计算机检索PubMed数据库1990-01/2007-02相关小分子干扰RNA和反义寡核苷酸方面的文献,检索词"siRNA;accessible site;antisense oligonucleotides;RNA Interference;mechanism;chemically modified siRNA;chemically modified oligonucleotides",限定文献语言种类为English。资料选择:对资料进行初审,选取有关小分子干扰RNA和反义寡核苷酸的文献,开始查找全文。纳入标准:关于RNA干扰和反义寡核苷酸作用机制的研究;探讨如何在mRNA上寻找小分子干扰RNA和反义寡核苷酸作用靶点的论文;解释反义寡核苷酸化学修饰和小分子干扰RNA分类的文章;应用小分子干扰RNA治疗肿瘤的探索性研究。排除标准:非原创性的文章。资料提炼:共检索到200多篇关于小分子干扰RNA和反义寡核苷酸的文献,最终纳入40篇符合标准的文献。资料综合:尽管小分子干扰RNA和反义寡核苷酸作用机制不尽相同,但两者在很多方面如选择mRNA的作用靶点、化学修饰和应用等方面,是相通的。研究反义寡核苷酸的经验可以使小分子干扰RNA的研究事半功倍。本文对小分子干扰RNA和反义寡核苷酸技术进行了比较,这将有助于小分子干扰RNA的研究与应用。结论:研究反义寡核苷酸技术的经验对小分子干扰RNA的研究有指导意义,小分子干扰RNA是非常有希望被用于肿瘤治疗的新型药物。 相似文献
708.
Linkage and physical mapping of X-linked lissencephaly/SBH (XLIS): a gene causing neuronal migration defects in human brain 总被引:6,自引:2,他引:6
Ross ME; Allen KM; Srivastava AK; Featherstone T; Gleeson JG; Hirsch B; Harding BN; Andermann E; Abdullah R; Berg M; Czapansky-Bielman D; Flanders DJ; Guerrini R; Motte J; Mira AP; Scheffer I; Berkovic S; Scaravilli F; King RA; Ledbetter DH; Schlessinger D; Dobyns WB; Walsh CA 《Human molecular genetics》1997,6(4):555-562
While disorders of neuronal migration are associated with as much as 25% of
recurrent childhood seizures, few of the genes required to establish
neuronal position in cerebral cortex are known. Subcortical band
heterotopia (SBH) and lissencephaly (LIS), two distinct neuronal migration
disorders producing epilepsy and variable cognitive impairment, can be
inherited alone or together in a single pedigree. Here we report a new
genetic locus, XLIS, mapped by linkage analysis of five families and
physical mapping of a balanced X;2 translocation in a girl with LIS.
Linkage places the critical region in Xq21-q24, containing the breakpoint
that maps to Xq22.3-q23 by high-resolution chromosome analysis. Markers
used for somatic cell hybrid and fluorescence in situ hybridization
analyses place the XLIS region within a 1 cM interval. These data suggest
that SBH and X-linked lissencephaly are caused by mutation of a single
gene, XLIS, that the milder SBH phenotype in females results from random
X-inactivation (Lyonization), and that cloning of genes from the breakpoint
region on X will yield XLIS.
相似文献
709.
Genetic variation in paraoxonase-2 is associated with variation in plasma lipoproteins in Canadian Oji-Cree 总被引:12,自引:0,他引:12
Robert A Hegele Stewart B Harris Philip W Connelly Anthony JG Hanley Lap-Chee Tsui Bernard Zinman Stephen W Scherer 《Clinical genetics》1998,54(5):394-399
We report studies of the association between genetic variation in PON2 and variation in plasma quantitative traits in a sample of 334 non-diabetic Oji-Cree. We detected associations between PON2 variation in codon 148 (Ala → Gly) and variation in fasting plasma concentrations of total and low-density lipoprotein (LDL) cholesterol and apolipoprotein (apo) B. In particular, homozygotes for a PON2 allele that encoded A148 had significantly higher plasma total, LDL cholesterol and apo B than subjects having the other two genotypes (p <0.01). Taken together, our results suggest that common genetic variation on chromosome 7q21.3–22.1 in PON2 is associated with significant variation of intermediate traits in plasma lipoprotein metabolism. 相似文献
710.