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排序方式: 共有404条查询结果,搜索用时 31 毫秒
1.
Occurrence of the t(2;5)(p23;q35) in non-Hodgkin's lymphoma 总被引:9,自引:3,他引:6
Weisenburger DD; Gordon BG; Vose JM; Bast MA; Chan WC; Greiner TC; Anderson JR; Sanger WG 《Blood》1996,87(9):3860-3868
Primary CD30(Ki-1)-positive anaplastic large-cell lymphoma (ALCL) is considered by some to be a distinct clinicopathologic entity associated with the t(2;5) (p23;q35). However, the specificity of t(2;5) for ALCL has not been carefully studied. Therefore, we performed a detailed analysis of all cases of ALCL with abnormal cytogenetics results in the Nebraska Lymphoma Study Group registry, as well as all other cases of non-Hodgkin's lymphoma with t(2;5) in the registry. We found the t(2;5) in only five of 10 cases of ALCL, four of whom were young patients. However, we also found the t(2;5) in 11 other cases of nonanaplastic lymphoma, including eight children with typical peripheral T-cell lymphomas of various types. The t(2;5) was also found in three older adults with B-cell lymphomas of various types. Thus, the t(2;5) was not specific for CD30+ ALCL. However, t(2;5) may define a clinicopathologic entity in children and young adults characterized by variable morphologies with a T-cell or indeterminate phenotype, CD30-positivity, nodal disease with frequent extranodal involvement, advanced stage, and an excellent response to therapy, including bone marrow transplantation for relapsed disease. The clinical relevance of the t(2;5) in older patients requires further study. 相似文献
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Two fast magnetic resonance (MR) imaging techniques, advanced Fourier and partial-flip imaging, were used at 0.35 T to examine 21 patients with suspected intracranial lesions; the results were quantitatively compared with a conventional spin-echo study. Both of the fast MR techniques yielded a fourfold reduction in imaging time per section. The advanced Fourier sequence showed contrast that was identical to the conventional spin-echo study with signal-to-noise ratios of 58% and 57% for the first and second echoes, respectively. The partial-flip sequence showed a contrast of 109% and 57% for lesions versus substantia alba, and 107% and 78% for substantia grisea versus substantia alba relative to the first and second echoes of the conventional spin-echo study. The partial-flip sequence was particularly sensitive to magnetic susceptibility; this produced artifacts that may undermine the usefulness of partial flip for routine screening in certain parts of the brain. However, this susceptibility significantly improved the detection of intracranial hemorrhage when compared with the spin-echo sequence, particularly when combined with phase mapping of the partial-flip study. 相似文献
4.
The effect of sterile inflammation and sepsis on the release of lactate and amino acids by peripheral tissues was investigated in rats by removing the splanchnic organs (liver + small intestines) from the circulation and monitoring changes in blood metabolites over 30 min. Functional hepatectomy was performed in rats 5-7 days following the intraperitoneal introduction of a fecal-agar pellet (sterile vs. Bacteroides fragilis + E. coli). Lactate was significantly (P less than .05) increased in each of the conditions following hepatectomy but was raised to a significantly greater extent in sepsis (P less than .05). A similar response was observed for glutamine while alanine was only significantly (P less than .05) increased in sepsis following hepatectomy. Branched chain amino acids (BCAA) showed differential changes in sepsis compared to control. In control and sterile inflammation, functional hepatectomy was associated with significant decreases (P less than .05) in BCAA. In sepsis, BCAA were not decreased following hepatectomy and were significantly (P less than .05) elevated relative to control or sterile inflammation. Phenylalanine concentrations were not altered in control or sterile inflammation but were significantly elevated in sepsis (P less than .05). Insulin attenuated the accumulation of lactate and amino acids in fed control animals, following functional hepatectomy. However, in septic animals, insulin failed to prevent the rise in plasma lactate following hepatectomy. 相似文献
5.
A PCR Specific for Escherichia coli O157 Based on the rfb Locus Encoding O157 Lipopolysaccharide 总被引:13,自引:0,他引:13 下载免费PDF全文
Patricia M. Desmarchelier Sima S. Bilge Narelle Fegan Leanne Mills James C. Vary Jr. Phillip I. Tarr 《Journal of clinical microbiology》1998,36(6):1801-1804
A PCR was developed for the detection of Escherichia coli O157 based on the rfbE O-antigen synthesis genes. A 479-bp PCR product was amplified specifically from E. coli O157 in cell lysates containing 200 or 2 CFU following crude DNA extraction. The PCR detected <1 CFU of E. coli O157 per ml in raw milk following enrichment. 相似文献
6.
Hart TC; Bowden DW; Bolyard J; Kula K; Hall K; Wright JT 《Human molecular genetics》1997,6(13):2279-2284
Tricho-dento-osseous syndrome (TDO), MIM# 190320, is transmitted as a
highly penetrant autosomal dominant trait that is characterized by variable
clinical expression. The principal clinical features include kinky/curly
hair in infancy, enamel hypoplasia, taurodontism, as well as increased
thickness and density of cranial bones. Possible genetic linkage has been
reported for TDO with the ABO blood group locus, but the gene defect
remains unknown. We have identified four multiplex families (n = 63, 39
affected, 24 unaffected) from North Carolina segregating TDO. We previously
have excluded a major locus for TDO in the ABO region for these families.
Utilizing a genome-wide search strategy, we obtained conclusive evidence
for linkage of the TDO syndrome locus to markers on chromosome 17q21
(D17S791, Z max = 10.54, Theta = 0.00) with no indication of genetic
heterogeneity. Multipoint analysis suggests the TDO locus is located in a 7
cM chromosomal segment flanked by D17S932 and D17S941. This finding
represents the first step towards isolation and cloning of the TDO gene.
Identification of this gene has important implications for understanding
normal and abnormal craniofacial development of hair, teeth and bone.
相似文献
7.
Missense mutation in a von Willebrand factor type A domain of the alpha 3(VI) collagen gene (COL6A3) in a family with Bethlem myopathy 总被引:2,自引:0,他引:2
Pan TC; Zhang RZ; Pericak-Vance MA; Tandan R; Fries T; Stajich JM; Viles K; Vance JM; Chu ML; Speer MC 《Human molecular genetics》1998,7(5):807-812
The Bethlem myopathy is a rare autosomal dominant proximal myopathy
characterized by early childhood onset and joint contractures. Evidence for
linkage and genetic heterogeneity has been established, with the majority
of families linked to 21q22.3 and one large family linked to 2q37,
implicating the three type VI collagen subunit genes, COL6A1 (chromosome
21), COL6A2 (chromosome 21) and COL6A3 (chromosome 2) as candidate genes.
Mutations of the invariant glycine residues in the triple-helical
domain-coding region of COL6A1 and COL6A2 have been reported previously in
the chromosome 21-linked families. We report here the identification of a
G-->A mutation in the N-terminal globular domain-coding region of COL6A3
in a large American pedigree (19 affected, 12 unaffected), leading to the
substitution of glycine by glutamic acid in the N2 motif, which is
homologous to the type A domains of the von Willebrand factor. This
mutation segregated to all affected family members, to no unaffected family
members, and was not identified in 338 unrelated Caucasian control
chromosomes. Thus mutations in either the triple-helical domain or the
globular domain of type VI collagen appear to cause Bethlem myopathy.
相似文献
8.
Role of the Escherichia coli O157:H7 O side chain in adherence and analysis of an rfb locus. 总被引:3,自引:0,他引:3 下载免费PDF全文
Shiga-toxigenic Escherichia coli strains belonging to serotype O157 are important human pathogens, but the genetic basis of expression of the O157 antigen and the role played by the lipopolysaccharide O side chain in the adherence of this organism to epithelial cells are not understood. We performed TnphoA mutagenesis on E. coli O157:H7 strain 86-24 to identify a mutant (strain F12) deficient in O-antigen expression. Nucleotide sequence analysis demonstrated that the transposon inserted within an open reading frame with significant homology to rfbE of Vibrio cholerae O1 (U. H. Stroeher, L. E. Karageorgos, R. Morona, and P. A. Manning, Proc. Natl. Acad. Sci. USA 89:2566-2570, 1992), which is postulated to encode perosamine synthetase. This open reading frame was designated rfbE(EcO157:H7). The guanine-plus-cytosine fraction (0.35) suggests that rfbE(EcO157:H7) may have originated in a species other than E. coli. rfbE(EcO157:H7) is conserved in nontoxigenic E. coli O157 strains expressing a variety of other flagellar antigens but is not found in E. coli O55:H7 strains, which are more closely related to E. coli O157:H7. Strain F12 was significantly more adherent to HeLa cells in a quantitative adherence assay than was its E. coli O157:H7 parent, but they did not differ in other phenotypes. Restoration of the expression of the O side chain by complementation of the TnphoA mutation in strain F12 by a plasmid expressing intact rfbE(EcO157:H7) reduced the adherence of the hyperadherent strain F12. We conclude that rfbE(EcO157:H7) is necessary for the expression of the O157 antigen, that acquisition of E. coli rfb genes occurred independently in E. coli O157:H7 and unrelated O157 strains, and that the O side chain of E. coli O157:H7 lipopolysaccharide interferes with the adherence of E. coli O157:H7 to epithelial cells. 相似文献
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