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31.
因为数字化学习环境是未来图书馆事业的发展趋势,文章从图书馆数字化学习环境的内涵开始,分析了医院图书馆数字化学习环境建设的必要性及其现实的可行性,提出了图书馆软件环境和硬件环境的建设及两者的有机结合是医院图书馆数字化学习环境建设的重要保障。 相似文献
32.
医院图书馆员继续教育若干问题研究 总被引:1,自引:0,他引:1
在分析医院图书馆员继续教育的核心内容和主要形式的基础上,作者探讨了医院图书馆员继续教育的途径。 相似文献
33.
We have constructed a series of promoter or upstream activating sequence (UAS)-probe plasmids carrying the Tn5-derived neomycin resistance gene whose seven additional ATG codons in the 5-untranslated region were completely or partially removed. When the deleted version of the neo sequence retaining only one additional ATG (NeoD) was expressed under the control of a TDH3 promoter whose UAS was deleted, the transformed cells were unable to grow at a low concentration of the antibiotic G418. In contrast with this, yeast cells expressing the NeoC sequence and having no additional ATG exhibited a high level of G418-resistance. Moreover, the UAS-probe system using NeoD has been successfully applied for the identification of several E. coli DNA sequences that clearly function as UASs in yeast cells. Two of these prokaryotic sequences with UAS activity were identified as a part of the coding region of the tgt and the hydG gene, respectively. 相似文献
34.
Primary structure of a variable region of the V kappa I subgroup (ISE) in light chain deposition disease. 总被引:2,自引:0,他引:2 下载免费PDF全文
A Rocca A A Khamlichi P Aucouturier L H Noël L Denoroy J L Preud'homme M Cogn 《Clinical and experimental immunology》1993,91(3):506-509
Although structural abnormalities of monoclonal immunoglobulin light chains (LC) are suspected to play a determinant role in non-amyloid light chain deposition disease (LCDD), this condition is as yet poorly documented at the molecular level, since only three sequences have been reported to date. In a case of myeloma-associated LCDD, the patient's urine contained an unglycosylated kappa Bence Jones protein made up of dimers and monomers with an apparent molecular mass of 25,000 which was assigned to the V kappa I subgroup by N-terminal amino acid sequencing. The complete variable region sequence of the monoclonal kappa chain produced by the malignant plasma cells was amplified by polymerase chain reaction (PCR) using small amounts of material obtained by bone marrow aspiration. The sequence of three independently amplified cDNA clones derived from a normal-sized kappa messenger RNA was identical to that of the urinary kappa chain. The kappa mRNA had an overall normal structure made up of a V kappa I sequence rearranged to J kappa I. Several unusual features of the variable region (the first complete V kappa I sequence reported in LCDD) included three substitutions that introduced hydrophobic residues at spatially close positions. The strategy associating N-terminal sequence determination and cDNA cloning by PCR could help in accumulating new sequence data and improving our understanding of LCDD pathogenesis. 相似文献
35.
Takeshi Tana Nobuhiro Kamikawaji Christopher J. Savoie Tohru Sudo Yurika Kinoshita T. Sasazuki 《Journal of human genetics》1998,43(1):14-21
Susceptibility to a series of autoimmune diseases is strongly associated with particular HLA class II alleles. Identification
of T cell clones and antigenic epitopes bound by HLA class II molecules involved in autoimmune diseases is critical to understanding
the etiology of these HLA class II-associated diseases. However, establishment of T cell clones in autoimmune diseases is
difficult because the antigenic peptides are unknown. Peptide library methods which include all possible peptide sequences
offer a potentially powerful tool for the detection of cross-reactive antigenic peptides recognized by T cells. Here, we reduced
the number of peptides per mixture by utilizing the known binding motifs of peptides for the HLA-DRB1*0405 molecule and evaluated
the effectiveness of this library design. Each library mixture evoked a strong proliferative response in the unprimed peripheral
blood lymphocytes (PBL) from HLA-DRB1*0405-positive donors but little or no response in the PBL from HLA-DRB1*0405-negative donors. The library also detected antigenic peptides that activated three antigen-specific T cell lines restricted
by HLA-DRB1*0405, with different specificities. The motif-based approach thus presents a powerful method for monitoring T
cells in large, heterogeneous T cell populations and is useful for the identification of the mimic peptide epitopes of T cell
lines and clones.
Received: October 3, 1997 / Accepted: October 23, 1997 相似文献
36.
Autoantibodies to dsDNA are an important diagnostic marker and pathogenic factor for systemic lupus erythematosus (SLE). Although the anti-dsDNA antibodies present in SLE are indicative of an antigen-driven response, the antigen has not been conclusively identified. The specific SLE anti-dsDNA antibodies were obtained by affinity purification using a dsDNA-coupled Sepharose column. Using the anti-dsDNA antibodies to screen a phage peptide display library, we demonstrated that purified polyclonal anti-dsDNA antibodies and a monoclonal anti-dsDNA antibody specifically bind a 15 mer peptide ASPVTARVLWKASHV. This chemically synthesized peptide could be recognized by anti-dsDNA antibodies in ELISA and Dot blot. This 15 mer peptide can inhibit anti-dsDNA antibodies binding to dsDNA antigen in immunoassays and in the Crithidia luciliae assay while a control peptide did not inhibit anti-dsDNA antibodies. This study demonstrates the potential usefulness of the peptide DNA surrogate in diagnostic tests of SLE and in the investigation of the origin of anti-dsDNA antibodies. It may also be used in studies of the DNA-anti-DNA antibody interaction. 相似文献
37.
Huang W Sher YP Delgado-West D Wu JT Peck K Fung YC 《Annals of biomedical engineering》2001,29(7):535-551
The remodeling of the pulmonary arterial tissue in response to a step change of the oxygen concentration in the gas in which a rat lives was recorded as function of time and function of O2 concentration. Three steps of changing from 20.9% to 17.2%, 13.6%, and 10% O2 were imposed. Earlier work in our laboratory has shown that pulmonary arterial tissue remodeling is significant in the first 24 h after a step change of oxygen tension. Hence we made measurements in this period. Furthermore, data were obtained for tissue remodeling of circumferential and axial lengths of the pulmonary arteries. We recorded the activities of gene expressions in the lung tissues by microarray, determined the dose response curves of gene expression in the homogenized whole lungs with respect to four levels of O2 concentration, and obtained the time courses of gene expression in the lung parenchyma in 30 days after a step decrease of O2 concentration from 20.9% to 10%. We would like to suggest that the correlation of gene expression with physiological function parameters, i.e., time, O2 tension, blood pressure, opening angle, wall thicknesses, etc., is the way to narrow down the search for specific genes for specific physiological functions. © 2001 Biomedical Engineering Society.
PAC01: 8719Uv 相似文献
38.
Nucleotide sequence of dengue type 3 virus genomic RNA encoding viral structural proteins 总被引:4,自引:0,他引:4
Kiyoshi Osatomi Isao Fuke Daisuke Tsuru Tadayoshi Shiba Yoshiyuki Sakaki Hideo Sumiyoshi 《Virus genes》1988,2(1):99-108
Complementary DNAs to the 5 proximal region of the dengue virus type 3 RNA were cloned into bacterial plasmids and the nucleotide sequence of 3,000 bases from the 5 terminus of the genome were determined by DNA and RNA sequencing methods using dideoxy chain-termination reactions. Comparison of the nucleotide sequence thus obtained with those of other flavivirus genomes revealed significant homology existing in nucleotide sequence of the flavivirus genomes. When we compared amino acid sequence deduced from the nucleotide sequence with those of other flaviviruses, this genome region was found to include sequences encoding three viral structural proteins C, M, and E and a part of the viral nonstructural protein NS1 in this order in addition to the 5-noncoding sequence. The characteristics and functions of these proteins were discussed based on the deduced amino acid sequences and their hydrophobic profiles. The genetic relationship of flaviviruses was also discussed based on the genetic variation observed in their genomes. 相似文献
39.
Transcriptome analysis in blastocyst hatching by cDNA microarray 总被引:1,自引:0,他引:1
Chen HW Chen JJ Yu SL Li HN Yang PC Su CM Au HK Chang CW Chien LW Chen CS Tzeng CR 《Human reproduction (Oxford, England)》2005,20(9):2492-2501
BACKGROUND: Hatching is an important process for early embryo development, differentiation and implantation. However, little is known about its regulatory mechanisms. By integrating the technologies of RNA amplification and cDNA microarrays, it has become possible to study the gene expression profile at this critical stage. METHODS: Pre-hatched and hatched ICR mouse embryos (25 blastocysts in each group were used in the triplicate experiments) were collected for RNA extraction, amplification, and microarray analysis (the mouse cDNA microarray, 6144 genes, including expressed sequence tags). RESULTS: According to cDNA microarray data, we have identified 85 genes that were expressed at a higher level in hatched blastocyst than in pre-hatched blastocysts. In this study, 47 hatching-related candidate genes were verified via re-sequencing. Some of these genes have been selected and confirmed by real-time quantitative RT-PCR. These hatching-specific genes were also expressed at a lower level in the delayed growth embryos (morula or blastocyst without hatching at day 6 post hCG). These genes included: cell adhesion and migration molecules [E-cadherin, neuronal cell adhesion molecule (NCAM), lectin, galactose binding, soluble 7 (Lgals7), vanin 3 and biglycan], epigenetic regulators (Dnmt1, and SIN3 yeast homolog A), stress response regulators (heme oxygenase 1) and immunoresponse regulators [interleukin (IL)-2-inducible T-cell kinase, IL-4R, interferon-gamma receptor 2, and neurotrophin]. The immunostaining of E-cadherin and NCAM showed strong and specific localization in hatched blastocyst. CONCLUSIONS: This work provides important information for studying the mechanisms of blastocyst hatching and implantation. These hatching-specific genes may have potential as new drug targets for controlling fertility. 相似文献
40.
DNA microarray analysis of gene expression profiles in deep endometriosis using laser capture microdissection 总被引:12,自引:0,他引:12