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1.
COLCOCK BP 《The Surgical clinics of North America》1949,29(3):829-841
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Motivation is an integral part of an effective organizational management scheme. In March 1992, we sent a survey designed to assess motivational preference to all certified athletic trainers in the State of Hawaii. The population included: 6 high school athletic trainers, 10 university athletic trainers, and 9 clinic athletic trainers. The surveys were completed and returned by 80% of the population. With the exception of being an integral part of a work team (p<.05), athletic trainers in the State of Hawaii showed little discrepancy in terms of motivation. Further, there are differences among the three groups of athletic trainers in rating the importance of motivators concerning being appreciated, receiving raises, and being an integral part of a team (p< .05) Differences in motivational factors among these three groups could be influenced by the organizational structure in which the athletic trainers operate. Further investigation should include a mainland population that includes athletic trainers in professional sports and the industrial setting. 相似文献
4.
Diagnosis of gastrointestinal stromal tumors: A consensus approach 总被引:258,自引:0,他引:258
Fletcher CD Berman JJ Corless C Gorstein F Lasota J Longley BJ Miettinen M O'Leary TJ Remotti H Rubin BP Shmookler B Sobin LH Weiss SW 《Human pathology》2002,33(5):459-465
As a result of major recent advances in understanding the biology of gastrointestinal stromal tumors (GISTs), specifically recognition of the central role of activating KIT mutations and associated KIT protein expression in these lesions, and the development of novel and effective therapy for GISTs using the receptor tyrosine kinase inhibitor STI-571, these tumors have become the focus of considerable attention by pathologists, clinicians, and patients. Stromal/mesenchymal tumors of the gastrointestinal tract have long been a source of confusion and controversy with regard to classification, line(s) of differentiation, and prognostication. Characterization of the KIT pathway and its phenotypic implications has helped to resolve some but not all of these issues. Given the now critical role of accurate and reproducible pathologic diagnosis in ensuring appropriate treatment for patients with GIST, the National Institutes of Health convened a GIST workshop in April 2001 with the goal of developing a consensus approach to diagnosis and morphologic prognostication. Key elements of the consensus, as described herein, are the defining role of KIT immunopositivity in diagnosis and a proposed scheme for estimating metastatic risk in these lesions, based on tumor size and mitotic count, recognizing that it is probably unwise to use the definitive term "benign" for any GIST, at least at the present time. 相似文献
5.
IL-18 induces the differentiation of Th1 or Th2 cells depending upon cytokine milieu and genetic background 总被引:7,自引:0,他引:7
Xu D Trajkovic V Hunter D Leung BP Schulz K Gracie JA McInnes IB Liew FY 《European journal of immunology》2000,30(11):3147-3156
The functional division of CD4(+) T cells into Th1 and Th2 subsets is generally accepted but the mechanisms leading to their preferential induction remain elusive. Cytokines are considered the main determining factors in the initial differentiation of precursor T cells into these distinct subsets. Thus, IL-12 drives Th1 cells whereas IL-4 drives Th2 cells. Recently IL-18, originally designated as IFN-gamma-inducing factor, has been reported to synergize with IL-12 in the induction of Th1 cells. We report here that IL-18 can also induce T cells to differentiate into Th2 cells, in the presence of TCR activation, either alone or together with IL-4. This effect of IL-18 is mediated primarily on CD4(+) T cells compared with CD8(+) T cells and is inhibited in the presence of IL-12. IL-18, however, has no effect on functionally committed Th2 cells.( )Moreover, the effect of IL-18 on Th2 cell development is differentially manifest in different mouse strains, suggesting profound underlying genetic influences. BALB/c mice infected with Leishmania major and treated with recombinant IL-18 developed exacerbated disease and enhanced Th2 response compared with untreated controls. These data therefore provide a novel mechanism for Th2 cell development. Thus, IL-18, a cytokine constitutively expressed by cells of the innate response, is capable of inducing Th2 cell differentiation in the absence of IL-4. 相似文献
6.
Efficiency of the ortho VITROS assay for detection of hepatitis C virus-specific antibodies increased by elimination of supplemental testing of samples with very low sample-to-cutoff ratios 下载免费PDF全文
Oethinger M Mayo DR Falcone J Barua PK Griffith BP 《Journal of clinical microbiology》2005,43(5):2477-2480
The clinical significance of specimens with low sample-to-cutoff (S/Co) ratios in the Ortho VITROS chemiluminescence assay (CIA) for detection of antibodies to hepatitis C virus (HCV) was evaluated. In one study of 482 CIA-reactive samples, none of the 83 samples with S/Co ratios of < 5 was HCV RNA positive. In a subsequent study, 332 samples with S/Co ratios of between 1 and 20 were tested with the recombinant immunoblot assay (RIBA). None of the 163 samples with S/Co ratios of < 5 was RIBA positive, 83% were RIBA negative, and 28 samples (18%) were RIBA indeterminate. HCV RNA and/or clinical evidence of hepatitis was not found in the 27 indeterminate cases examined. These results show that over 99% of samples with very low S/Co ratios (< or = 5) have no evidence of HCV infection. Therefore, we suggest that the HCV antibody testing algorithm for the VITROS assay might be modified to eliminate supplemental testing of samples with very low S/Co ratios. 相似文献
7.
Rich JD Dickinson BP Macalino G Flanigan TP Towe CW Spaulding A Vlahov D 《Journal of acquired immune deficiency syndromes (1999)》1999,22(2):161-166
This study explores recent temporal trends in HIV prevalence among women entering prison and the incidence and associated risk factors among women reincarcerated in Rhode Island. Results from mandatory HIV testing from 1992 to 1996 for all incarcerated women were examined. In addition, a case control study was conducted on all seroconverters from 1989 to 1997. In all, 5836 HIV tests were performed on incarceration in 3146 women, 105 of whom tested positive (prevalence, 3.3%). Between 1992 and 1996, the annual prevalence of HIV among all women known to be HIV-positive was stable (p = .12). Age >25 years, nonwhite race, and prior incarceration were associated with seropositivity. Of 1081 initially seronegative women who were retested on reincarceration, 12 seroconverted during 1885 person-years (PY) of follow-up (incidence, 0.6/100 PY). Self-reported injection drug use (IDU; odds ratio [OR], 3.7; 95% confidence interval [CI], 1.3-10.1) was significantly associated with seroconversion, but sexual risk was not (OR, 1.1; 95% CI, 0.4-3.5). Incarceration serves as an opportunity for initiation of treatment and linkage to community services for a population that is at high risk for HIV infection. 相似文献
8.
Monoclonal antibody production (mAb) first requires the availability of large amounts of pure immunogen for animal immunisation and fusion screening procedures. To overcome this obstacle, we have developed a simple method for rapid generation of pure antigen by generation of recombinant protein containing the antigen of interest fused to the hinge and Fc domains of human immunoglobulin (Ig). The Fc domain forms a convenient 'tag' to enable detection of the protein in supernatant of transfected cells and for purification of immunogen by protein A affinity chromatography. The only requirement for immunogen preparation using this methodology is that a DNA sequence encoding a portion of the molecule of interest is known and that a suitable PCR template is available. Antibody production can be tailored to specific protein domains, for example functional domains, by expressing solely those domains in the fusion protein. We illustrate the technique with two different fusions used to raise antibodies against the porcine and human analogues of a complement (C) regulatory protein, decay accelerating factor (DAF) (CD55). Use of the specific Ig-fusion protein and a control protein facilitated screening of fusions by ELISA. We demonstrate two expression systems used to generate Ig fusion proteins, the first utilised a commercial vector to incorporate an amino terminal leader sequence and carboxy terminal Ig domains. Low levels of expression required subcloning into a high expression vector and resulted in yields of fusion protein at between 2 and 10 mg per litre of supernatant. The second expression system utilised the high expression vector directly, Ig domains of the chosen immunoglobulin isotype were amplified from peripheral blood mononuclear cell (PBMC) RNA and ligated into the vector in frame with DNA encoding the antigen. We describe potential pitfalls that may be encountered while using Ig fusion proteins as immunogen and demonstrate ways in which to tailor their design for optimal mAb production. 相似文献
9.
Early-onset gastric carcinomas display molecular characteristics distinct from gastric carcinomas occurring at a later age 总被引:5,自引:0,他引:5
Carvalho R Milne AN van Rees BP Caspers E Cirnes L Figueiredo C Offerhaus GJ Weterman MA 《The Journal of pathology》2004,204(1):75-83
Gastric cancer is thought to result from a combination of environmental factors and accumulation of specific genetic alterations, and consequently mainly affects older patients (>50 years of age). Fewer than 10% of patients present with the disease before 45 years of age and these young patients are thought to develop carcinomas with a different molecular genetic profile from that of sporadic carcinomas occurring at a later age. Forty early-onset gastric carcinoma resection specimens were characterized for microsatellite instability (MSI) and loss of heterozygosity status using 22 polymorphic microsatellite markers. Twenty-four biopsies were additionally evaluated for the presence of MSI. No MSI was observed in any of the cases analysed. Losses were infrequent, but were most common for the D1S234 (26.1%) and D1S1676 (17.4%) markers, flanking the RUNX3 gene; for the p53ALU (23.1%) and TP53 (15.4%) markers, near the TP53 gene; and for the D16S2624 (17.2%) marker, near the E-cadherin (CDH1) gene. All cases with loss of CDH1, as well as 6/7 cases with loss of TP53, displayed aberrant staining of the corresponding proteins, pointing to a functional role for these proteins in early-onset gastric carcinogenesis. No germline CDH1, TP53 or RUNX3 mutations were detected in any of the cases analysed. No correlation was observed between non-functional E-cadherin and the histological type of the tumours analysed. Finally, Epstein-Barr virus was not detected in any of the cases analysed. On the basis of these results, early-onset gastric carcinomas appear to have characteristics distinct from gastric carcinomas occurring at a later age. 相似文献
10.
We investigated the effects of suppression of complement activation at C3 level and inhibition of C5a on acute synovitis in rats. Acute synovitis was induced in Wistar rats by intra-articular (i.a.) injection into one knee of 0.3 mg of MoAb 6D1 (anti-rat CD59 antibody). In the treatment groups, soluble CR1 (sCR1) or C5a receptor (C5aR) antagonist was administered intra-articularly or intravenously and effects on the course of the acute synovitis were monitored. Synovitis induced by 6D1 was characterized by joint swelling, thickening of synovial tissue, cellular infiltration and deposition of membrane attack complex (MAC) on the synovial surface. Neither inflammatory change nor MAC deposition was found in rats which received an i.a. injection of sCR1 to suppress complement activity in the joint. Intra-articular injection of sCR1 did not reduce plasma complement activity. Intravenous administration of sCR1 suppressed plasma complement activity but had no effect on the course of the arthritis and synovitis with MAC deposition was observed. Neither i.a. nor i.v. injection of C5aR antagonist had any suppressive effects on inflammatory change or MAC deposition in synovium. The data show that inflammatory change induced by 6D1 was mediated by local complement activation and was not accompanied by systemic complement activation. C5a generation was not responsible for the observed inflammation, suggesting that other complement activation products, possibly MAC, mediate the inflammatory change observed in this model of acute synovitis in rats. 相似文献