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11.
Fluorescence in situ hybridization (FISH) with α-satellite DNA probes was used to study whole-arm chromosome translocation products in a family in which the propositus was shown to have a monosomy 18p/trisomy 20p imbalance. By this approach, we show that the chromosome 18 α-satellite DNA block is split into 2 smaller units, whereas the chromosome 20 breakpoint is not included within the α-satellite DNA region. We found no evidence to suggest that this split α-satellite DNA region has reduced or impaired the function of the centromere or that it contributed to the phenotype of the propositus. The FISH technique critically demonstrated the involvement of a whole-arm translocation in this case and provided accurate identification of breakpoints, which was not possible with standard banding techniques. © Wiley-Liss, Inc. 相似文献
12.
Three representations of the conditional independences due toMendelian segregation of genes in a pedigree are proposed. Thecomputational costs of performing calculations using the techniqueof peeling with each of these representations is compared byconsidering the weights of triangulations of the graph producedby each representation. 相似文献
13.
目的:探讨HBcAg显性失活突变体质粒pCDNA4-C-GFP的构建及体外表达。方法:选择编码乙肝核心抗原C基因片段及绿色荧光蛋白(green fluorescent protein,GFP)基因片段,利用基因重组技术构建成DNA质粒pCDNA4-C-GFP,并将该质粒转染肝癌细胞株HepG2。结果:通过RT-PCR检测到其RNA的表达,Confocal观察到GFP绿色荧光。结论:HBcAg显性失活突变体质粒pCDNA4-C-GFP的构建成功可以进行对HBV作用的研究。 相似文献
14.
A. Baxov P. Maroteaux J. Baroov I. Netriov 《American journal of medical genetics. Part A》1994,49(3):263-265
Two sibs with omodysplasia were born to phenotypically normal but consanguineous parents. They had severe micromelic dwarfism, facial anomalies, and mental retardation. One had a congenital heart defect. The radiographic findings are typical: hypoplastic distal end of the humerus with radioulnar diastasis. Parental consanguinity and clinical manifestations in 2 sibs suggest autosomal recessive inheritance. © 1994 Wiley-Liss, Inc. 相似文献
15.
Objective To investigate the effect of rosiglitazone on p38 mitogen-activated protein kinase (p38MAPK) pathway in polycystic kidney cyst-lining epithelial cells. Methods The cyst-lining epithelial cells (PKD cells) from human polycystic kidney were treated with rosiglitazone (10 μmol/L), peroxisome proliferator-activated receptor-γ (PPARγ) inhibitor GW9662 (10 μmol/L), rosiglitazone (10 μmol/L) +GW9662 (10 μmol/L), p38MAPK specific inhibitor SB203580 (10 μmol/L), SB203580 (10 μmol/L)+ rosiglitazone(10 μmol/L) for 2 hours followed by epidermal growth factor (EGF) stimulation. Protein expressions of p38, phuspho-p38 (p-p38) and proliferating cell nuclear antigen (PCNA) were detected by Western blot. p38 mRNA was examined by RT-PCR. Expression of c-fos and c-jun was observed by immunocytochemistry. Results (1) EGF markedly up-regulated the expressions of p38, p-p38, PCNA, c-fos anti c-jun compared with control group (P<0.01). (2) Compared with EGF treated group, rosiglitazone significantly reduced p38 activation and mRNA expression (P<0.01, respectively). Rosiglitazone, rosiglitazone+SB203580 could significantly down-regulated p-p38, PCNA, c-fos and c-jun expression (P<0.01, respectively) with no significant difference between these two groups. (3) GW9662 partially reversed the reduction effect of rosiglitazone. Conclusions Rosiglitazone can inhibit proliferation of autosomal dominant polycystic kidney disease cyst-lining epithelial cells partially through down-regulating p38 activation and reducing c-fos, c-jun and PCNA expression. The above effect of rosiglitazone is in part PPARγ-independcnt. 相似文献
16.
17.
Rainer Pankau Carl-Joachim Partsch Johannes Funda Wolfgang Günther Sippell 《American journal of medical genetics. Part A》1992,43(3):513-516
We report on the hypothalamic-pituitary-gonadal function in 2 male infants with the Smith-Lemli-Opitz (SLO or RSH) syndrome. Both infants had abnormal external genitalia. Basal and LHRH stimulated plasma gonadotropins were normal for age (1 month). Plasma testosterone, androstenedione, and dehydroepiandrosterone sulfate were normal for age and sex. Some forms of congenital adrenal hyperplasia (17,20-desmolase deficiency, 17α-hydroxylase deficiency, and 3β-hydroxysteroid dehydrogenase deficiency) were ruled out by hormonal studies. The endocrinological findings indicate a normal hypothalamic-pituitary-gonadal function and a normal adrenal steroid biosynthesis in these 2 patients. A partial androgen receptor defect causing the genital malformations seems possible in one patient. Whether 5α-reductase deficiency is the cause of the male pseudohermaphroditism in SLO syndrome remains the subject of future studies. © 1992 Wiley-Liss, Inc. 相似文献
18.
Methylation is an important pathway in the biotransformation of many drugs, neurotransmitters, and xenobiotic compounds. Histamine N-methyltransferase (HNMT) catalyzes the Nτ-methylation of histamine and structurally related compounds. Measurement of HNMT activity in the RBC makes it possible to access variation in the enzyme activity that may reflect differences in less accessible tissues such as brain. Previously reported high family correlations for RBC HNMT activity suggested that genetic inheritance plays a major role in the regulation of variation in this enzyme. In the present study we completed complex segregation analyses of RBC HNMT activity of 241 individuals in 51 nuclear families that were randomly ascertained through children in the Rochester, Minnesota public school system in order to characterize the mode of inheritance of this important enzyme. We found evidence for major gene influence on the regulation of RBC HNMT activity. Both transformed and untransformed data support the presence of Mendelian major gene segregation, but the gene frequency differences do not indicate a direct correspondence between genotypes inferred from the two sets of analyses. Analyses of the skewed untransformed data indicated the presence of a relatively rare (Q = 0.121) additive major gene for high activity, with the three overlapping genotype distributions representing 77, 21, and 2 % of individuals. Analyses of the normalized transformed data indicated the presence of a common (Q = 0.71) additive major gene for high activity, with the three overlapping genotype distributions accounting for 9, 41, and 50 % of individuals. The analyses of transformed data give the best fit as well as the most parsimonious Mendelian major gene model. However, we cannot rule out the possibility of multiple alleles, and analyses of untransformed data provide some support for a third allele. Molecular studies will be needed to validate and characterize the alleles that regulate RBC HNMT activity levels in humans. © 1993 Wiley-Liss. Inc. 相似文献
19.
Observations on two members of the Swedish family with congenital dyserythropoietic anaemia,type III
S. N. Wickramasinghe A. Wahlin D. Anstee S. F. Parsons G. Stopps I. Bergstrom M. Eriksson H. Sandstrom S. Shiels 《European journal of haematology》1993,50(4):213-221
Abstract: Two affected individuals of the Swedish family with CDA, type III, in which the disease is transmitted as an autosomal dominant character, were studied. Both cases displayed features hitherto undescribed in this family but described in patients with CDA, type III, in whom the inheritance may have been as an autosomal recessive character. Such features were: (a) haemosiderinuria, (b) grossly disorganised erythroblast nuclei, (c) differences in the ultrastructural appearances of individual nuclei within the same multinucleate erythroblast and (d) intraerythroblastic inclusions resembling precipitated globin chains. In both cases the giant mononucleate erythroblasts and the multinucleate erythroblasts had total DNA contents up to 28c (1c = haploid DNA content) and 48c respectively, and some DNA synthesising bi- and multinucleate erythroblasts contained one or more nuclei which were unlabelled with 3H-thymidine. These findings are similar to those in patients with the autosomal recessive type of disease. Thus no major phenotypic differences are yet apparent between cases of CDA, type III, with different patterns of inheritance. Analysis of the surface erythrocyte proteins of the 2 Swedish CDA, type III, patients with monoclonal antibodies recognising Band 3, glycophorins A, B, C and D, Rh, CD44, CD47, CD55, CD58, CD59, Lutheran, Kell, LW and acetylcholinesterase did not reveal any gross abnormality of expression of these proteins. A slightly altered expression of blood group antigens A and H was revealed by the lectins Dolichos biflorus and Ulex europaeus and the Mr of Band 3 as judged by SDS polyacrylamide gel electrophoresis was also slightly reduced, suggesting that there may be minor alterations in the degree of N-glycosylation of some red cell membrane constituents. 相似文献
20.
P. S. Karnes A. T. Shamban D. R. Olsen M. J. Fazio R. E. Falk 《American journal of medical genetics. Part A》1992,42(1):29-34
Several “progeroid” syndromes have now been identified. The De Barsy syndrome is an autosomal recessive syndrome of dwarfism, mental deficiency, an “aged” appearance at birth, abnormal elastic fibers on skin biopsy, and lax skin, large helices, eye abnormalities, lax joints, hypotonia, and athetoid posturing. We report one case and review 11 cases from the literature. To understand the abnormal appearance of the elastic fibers on biopsy, we performed elastin gene expression studies on fibroblasts cultured from our patient's skin. Molecular hybridization studies revealed reduced elastin mRNA steady-state levels as compared with age matched control individuals. Assuming normal rates of mRNA translation, reduced elastin synthesis would occur. Diminished dermal elastin content could explain the altered cutaneous elasticity, decreased elastic fibers in the skin, and many clinical manifestations of individuals with this condition. 相似文献