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31.
A high molecular weight arabinogalactan protein (AGP) from the pressed juice of Echinacea purpurea, known to exhibit immunomodulatory properties in vitro, was characterized. Alkaline hydrolysis was carried out, leading to
degradation of the protein core and to carbohydrate moieties linked to the amino acid responsible for binding. Gel permeation
chromatography of these AG subunits gave one peak with a molecular weight of 30 × 103 Da. Hydroxyproline (42.9% w/w) was detected as the dominant amino acid after alkaline hydrolysis and was thus identified as
the major amino acid responsible for the binding between the protein and the AG subunits via an O-glycosidic linkage. Large
amounts of glutamine/glutamic acid (24.5% w/w) and asparagine/aspartic acid (17.3% w/w) were also found. Polyclonal antibodies
raised against the intact AGP were shown to bind to the AG subunits too, indicating that the epitopes responsible for such
interactions are localized in the polysaccharide moiety of the AGP. 相似文献
32.
Steven J. Davidson MD MBA Frank L. Zwemer Jr. MD MBA Larry A. Nathanson MD Kenneth N. Sable MD Abu N.G.A. Khan MD MS 《Academic emergency medicine》2004,11(11):1127-1134
Physician-generated emergency department clinical documentation (information obtained from clinician observations and summarized decision processes inclusive of all manner of electronic systems capturing, storing, and presenting clinical documentation) serves four purposes: recording of medical care and communication among providers; payment for hospital and physician; legal defense from medical negligence allegations; and symptom/disease surveillance, public health, and research functions. In the consensus development process described by Handler, these objectives were balanced with the consideration of efficiency, often evaluated as physician time and clinical documentation system costs, in recording the information necessary for their accomplishment. The consensus panel session participants and authors recommend that 1) clinical documentation be electronically retrievable; 2) selection and implementation be evidence-based and grounded on valid metrics (research is needed to identify these metrics); 3) the user interface be crafted to promote clinical excellence through high-quality information collection and efficient charting techniques; 4) the priorities for integration of clinical information be standardized and implemented within enterprises and across health and information systems; 5) systems use accepted standards for bidirectional, real-time clinical data exchange, without limiting the location or number of simultaneous users; 6) systems fully utilize existing electronic sources of specific patient information and general medical knowledge; 7) systems automatically and reliably capture appropriate data that support electronic billing for emergency department services; and 8) systems promote bedside documentation and mobile access. 相似文献
33.
《Movement disorders》2003,18(11):1240-1249
The identification of disease genes using family‐based approaches has provided important insights into the pathogenesis of Parkinson's disease (PD) demonstrating the importance of genetic studies on monogenic forms of the disease. We studied a large Cuban family with typical, late‐onset PD and probable autosomal dominant inheritance. Mean age at onset was 61.2 years (±12.53, 45–76). Other phenotypes such as essential tremor and atypical parkinsonism were observed in this family. We carried out a genome‐wide scan and linkage analyses. The genetic data were analyzed using a conservative model in which only patients with clinically definite or likely PD were considered affected, other phenotypes were regarded as “unknown.” Multipoint analyses yielded a maximum LOD of 2.26 between markers D19S221 and D19S840. Haplotype analysis showed a region on chromosome 19 shared by six of seven PD patients. The essential tremor phenotype and the atypical parkinsonism do not segregate with this haplotype, suggesting a different etiology. Our findings suggest the presence of a novel locus for PD on chromosome 19p13.3–q12. We propose that an oligogenic model with moderate contribution of two or three genes rather than a “pure” monogenic model might explain better the wide range in age at onset, the reduced penetrance and the phenotypical variability observed in PD families. © 2003 Movement Disorder Society 相似文献
34.
Hemophilia A: genetic prediction and linkage studies in all available families in Finland 总被引:1,自引:0,他引:1
Anna-Elina Lehesjoki Pertti Sistonen Vesa Rasi Albert de la Chapelle 《Clinical genetics》1991,39(3):199-209
RFLP studies were done in 82 (75%) of all known hemophilia A families in the Finnish population (approximately 5 million). Two intragenic RFLPs (Bc1I/F8A, XbaI/p482.6) and two extragenic markers (TaqI/St14, Bg1II/DX13) were used. Among 263 females at risk, carriership could be evaluated with an intragenic marker in 47% and with an extragenic marker in 26%. In 27% of the females, carriership could be neither excluded nor confirmed; 68% of these females were relatives of an isolated patient. Eight recombinations between the factor VIII gene (F8C) and DXS52 (lod 25.02 at theta max 0.06), eight recombinations between F8C and DXS15 (lod 21.91 at theta max 0.05), and two recombinations between DXS52 and DXS15 (lod 33.56 at theta max 0.01) were found. Using multipoint linkage analysis, the most likely order of loci supported by the data was: F8C-DXS15-DXS52-DXS134. RFLP segregation analysis provides a highly useful method of carrier detection and prenatal diagnosis of hemophilia A, but its limitations must be carefully taken into account. 相似文献
35.
Practices of reading and writing: the constitutive role of the patient record in medical work 总被引:2,自引:0,他引:2
Marc Berg 《Sociology of health & illness》1996,18(4):499-524
This paper contributes to a reappraisal of the sociological significance of the medical record. Building upon re-evaluations of the notion of ‘representation’ in ethnomethodological and science and technology studies, it attempts to portray the medical record as an artefact which mediates the social relations that act and work through it. Through practices of reading and writing, it is argued, the medical record figures as a fundamental, constitutive element of medical practice. To address some of the dimensions that are involved, three case fragments are discussed. The way the medical record enters into the process of ‘medical decision making’ in the doctor-patient interaction, and into that interaction itself, is discussed first. Subsequently, some aspects of how the record mediates medical work as it is performed in the wards of a hospital are outlined. A third instance of its prominent role demonstrates how practices of reading and writing tend to produce particular renderings of patients’ histories - including notions of how medical work is structured. 相似文献
36.
Michael?N.?Romanov Laura?M.?Daniels Jerry?B.?Dodgson Mary?E.?DelanyEmail author 《Chromosome research》2005,13(2):215-222
The chicken genome, like those of most avian species, contains numerous microchromosomes that cannot be distinguished by size
alone. Unique properties attributed to the microchromosomes include high GC content and gene density, and an enhanced recombination
rate. Previously, microchromosome GGA 17 was shown to align with the consensus genetic linkage group E41W17, and bacterial
artificial chromosome (BAC) clones containing E41W17 markers were isolated and assigned on the physical BAC map as well as
the recently assembled draft chicken genome sequence. For this study, these same BACS were utilized as probes for fluorescence
in-situ hybridization (FISH) to develop the GGA 17 cytogenetic map. Here we detail the chromosome order of ten BAC DNAs, thereby
deriving a cytogenetic map of GGA 17 that is simultaneously integrated with both the linkage map and genome sequence. The
location of the FISH probes together with the morphological appearance of the chromosome suggested that GGA 17 is an acrocentric
chromosome whose cytogenetic map orientation is reversed from that currently indicated by the linkage map and draft genome
sequence. The reversed orientation and the centromere location of GGA 17 were confirmed experimentally by dual-colour FISH
hybridization using terminal BACs and the centromere-specific CNM oligonucleotide as probes. An advantage of this cyto-genomic
approach is the improved alignment of the sequence and linkage maps with cytogenetic features such as the centromere, telomeres,
p and q arms, and staining patterns indicating GC versus AT content. 相似文献
37.
甲叉四氢叶酸还原酶C677T与精神分裂症的连锁不平衡研究 总被引:2,自引:0,他引:2
目的 通过对甲叉四氢叶酸还原酶(methylenetetrahydrofolate reductase,MTHFR)C677T错义突变与精神分裂症的连锁不平衡研究,探讨该突变与精神分裂症的关系。方法 对115个精神分裂症同胞及核心家系中,用XDT和MAPMAKER/SIBS软件系统进行MTHFRC677T与精神分裂症的连锁不平衡分析。按照不同的诊断范围将家系分类,分别在全体家系及发病年龄小于25岁的家系中进行连锁不平衡分析。结果 在4种不同的诊断分类下,对全体家系进行连锁不平衡分析未发现阳性结果。对发病年龄小于25岁的患者家系进行分析时发现,在4种不同的诊断灵感上均具有显著性意义,P值分别小于0.05及0.01。结论 MTHFR C677T错义突变可能为影响精神分裂症易感性的基因之一,尤其是在发病年龄较早的患病群体中。 相似文献
38.
39.
Takeda H Matsumura Y Kuwata S Nakano H Shanmai J Qiyan Z Yufen C Kusuoka H Matsuoka M 《International journal of medical informatics》2004,73(3):311-316
To enhance medical cooperation between the hospitals and clinics around Osaka local area, the healthcare network system, named Osaka Community Healthcare Information System (OCHIS), was established with support of a supplementary budget from the Japanese government in fiscal year 2002. Although the system has been based on healthcare public key infrastructure (PKI), there remain security issues to be solved technically and operationally. An experimental study was conducted to elucidate the central and the local function in terms of a registration authority and a time stamp authority in contract with the Japanese Medical Information Systems Organization (MEDIS) in 2003. This paper describes the experimental design and the results of the study concerning message security. 相似文献
40.