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71.
Immunogenetic studies in families with rheumatoid arthritis and autoimmune thyroid disease. 下载免费PDF全文
P A Sanders D M Grennan P A Dyer G G de Lange R Harris 《Journal of medical genetics》1985,22(6):451-456
HLA and Gm typing were carried out in 16 families. Seven families included 10 sib pairs with rheumatoid arthritis (RA) and autoimmune thyroid disease (ATD) respectively, and nine families included 16 sib pairs with RA and circulating thyroid autoantibodies respectively. Eight, 11, and seven sib pairs with either RA or clinical or immunological evidence of ATD shared none, one, and two HLA haplotypes respectively, and two, seven, and two informative sib pairs shared none, one, and two Gm haplotypes respectively. This random haplotype sharing of HLA and Gm haplotypes suggests that non-HLA, non-Gm linked genes are likely to be involved in any genetic predisposition common to RA and ATD. 相似文献
72.
73.
The purpose of this research was to investigate possible explanations for why small-diameter microfiber implants do not experience encapsulation in subcutaneous tissue as do large-diameter fiber implants. Single polypropylene microfibers of approximately rectangular cross-section with rounded edges were twisted about their longitudinal axes and affixed at their ends to polycarbonate frames. The frames were implanted in rat subcutaneous dorsum for a 5-week period, then removed and processed for light microscopy analysis. Fibrous capsule presence/absence and thickness around the implants were assessed, and their relationships to geometric features of the fibers investigated. A logistic regression analysis between presence/absence of a fibrous capsule and geometric features of interest demonstrated strong predictive ability (92.4% correct predictions) for implant height and a well-defined threshold separating the presence and absence of a fibrous capsule at 5.9 microm (p < 0.001). Implant height was defined as the vertical distance between the most superficial and deepest level of the implant. This 5.9-microm threshold value of implant height is comparable to the 6.0-microm diameter threshold for capsule presence/absence in fibers of circular cross-section [Sanders et al. J Biomed Mater Res 2000; 52(1):231-237]. Fiber major axis length, minor axis length, aspect ratio, surface area per unit length, implant width, and implant angle did not show similar predictive ability or a well-defined threshold separating the presence and absence of a fibrous capsule. It is reasoned that for fibers greater than the threshold height of 5.9 microm, separation of collagen fibers in the extracellular matrix creates dead space regions adjacent to the fibers that attract inflammatory cells and stimulate fibrous capsule formation. 相似文献
74.
Sanders A 《The AIDS reader》1999,9(8):580-583
Bacterial pneumonia is the most common cause of death from pneumonia in patients with HIV disease, causing greater mortality than Pneumocystis carinii pneumonia. The challenge for the clinician evaluating the HIV-infected patient with pneumonia is to quickly distinguish clinically among all possible causes and to initiate therapy based on the most likely diagnosis. While an understanding of typical clinical and radiographic presentations is essential, bronchoscopy is the preferred test for reliably identifying the causative organism. 相似文献
75.
Sanders JE Lamont SE Mitchell SB Malcolm SG 《Journal of biomedical materials research. Part A》2005,72(3):335-342
The purpose of this research was to determine if fiber spacing for small fiber diameter fibro-porous meshes affected tissue response in vivo. Disk-shaped polyurethane meshes, with mean fiber diameters of 7.6 microm and fiber spacing between 6 and 68 microm, were implanted in rat subcutaneous dorsum for 5-week intervals and then prepared for light microscopy and morphological analysis. Results showed that implants with 12- to 68-microm spacing had no histologically apparent fibrous capsule around the perimeter, a result different from that for 6-microm spacing samples that had a capsule around a mean of 34.2% of the perimeter. For the 12- to 68-microm spacing range, a mean of 21.0% of individual fibers within the meshes were encapsulated. Qualitatively, it appeared that larger fibers were encapsulated more frequently than smaller ones. When nodeless or baggy meshes were implanted, cells tended to cluster three or more fibers into groups and then encapsulate each group. Over the 6- to 68-microm spacing range, cell nuclei volume fraction within the meshes increased from the 6- to the 29-microm spacing (p = 0.000) and then decreased from the 29- to the 68-microm spacing (p = 0.015). There was a trend of an increase in local vessel volume fraction with spacing over the 6- to 68-microm range, though the relationship was weak. The results indicate that the reason for the lack of encapsulation of small-fiber fibro-porous meshes is not exclusively a pore boundary explanation, as is proposed for small-pore porous meshes. 相似文献
76.
Objective: To evaluate which of 24 β-lactams used in susceptibility tests best discriminated between strains of Klebsiella pneumoniae and Escherichia coli that produce extended spectrum β-lactamases (ESBLs) from strains that produce older, more familiar, plasmid-mediated β-lactamases such as TEM-1 and SHV-1.
Methods: Susceptibility to the 24 β-lactam agents was determined by agar dilution and disk diffusion methodologies, using 27 strains of K. pneumoniae and E. coli that produced 22 different older plasmid-mediated β-lactamases and 28 strains that produced 17 different ESBLs.
Results: In general, strains that produced ESBLs were intermediate or resistant to cefpodoxime, whereas those that produced other β-lactamases were susceptible to this agent. The agar dilution test exhibited 96% sensitivity and 100% specificity in discriminating these two groups of organisms. The disk diffusion test exhibited 100% sensitivity and 96% specificity. All other β-lactam agents tested were inferior discriminators between the two groups of organisms.
Conclusions: Agar dilution and disk diffusion tests with cefpodoxime can be used to discriminate strains of K. pneumoniae and E. coli that produce ESBLs from those that produce older, plasmid-mediated β-lactamases. 相似文献
Methods: Susceptibility to the 24 β-lactam agents was determined by agar dilution and disk diffusion methodologies, using 27 strains of K. pneumoniae and E. coli that produced 22 different older plasmid-mediated β-lactamases and 28 strains that produced 17 different ESBLs.
Results: In general, strains that produced ESBLs were intermediate or resistant to cefpodoxime, whereas those that produced other β-lactamases were susceptible to this agent. The agar dilution test exhibited 96% sensitivity and 100% specificity in discriminating these two groups of organisms. The disk diffusion test exhibited 100% sensitivity and 96% specificity. All other β-lactam agents tested were inferior discriminators between the two groups of organisms.
Conclusions: Agar dilution and disk diffusion tests with cefpodoxime can be used to discriminate strains of K. pneumoniae and E. coli that produce ESBLs from those that produce older, plasmid-mediated β-lactamases. 相似文献
77.
Detection of extended-spectrum-beta-lactamase-producing members of the family Enterobacteriaceae with Vitek ESBL test. 总被引:5,自引:1,他引:5 下载免费PDF全文
C C Sanders A L Barry J A Washington C Shubert E S Moland M M Traczewski C Knapp R Mulder 《Journal of clinical microbiology》1996,34(12):2997-3001
A three-phase analysis of the Vitek ESBL test and a double-disk (2 disk) test was performed to assess their ability to detect extended-spectrum beta-lactamases (ESBLs) in members of the family Enterobacteriaceae. In the first two phases involving detection of ESBLs in 157 stains processing well-characterized beta-lactamases, sensitivity and specificity were found to be 99.5 and 100%, respectively, for the Vitek ESBl test and 98.1 and 99.4%, respectively, for the 2-disk test. In the third phase, in which the ability of each test to detect ESBLs in 295 clinical isolates was assessed, there was only one false positive (Vitek ESBL test). Across all three phases, the Vitek ESBL test was found to be much easier to perform than the 2-disk test. The latter also involved subjective interpretation of results. There were a total of 176 Escherichia coli and 157 Klebsiella pneumoniae isolates and less than 40 isolates of each of 14 other species evaluated. In a supplemental study of Klebsiella oxytoca, an organism possessing a chromosomal beta-lactamase similar to an ESBL, the Vitek ESBL test was found to be capable of detecting hyperproduction of this enzyme in strains of this species as well. These data indicate that the Vitek ESBL test is reliable for the detection of ESBLs in E. coli and K. pneumoniae, the two species in which ESBLs are most common, and of hyperproduction of the K. oxytoca beta-lactamase, a situation which engenders a level of resistance to this species similar to that seen with ESBLs. 相似文献
78.
Paul J Martin George B McDonald Jean E Sanders Claudio Anasetti Frederick R Appelbaum H Joachim Deeg Richard A Nash Effie W Petersdorf John A Hansen Rainer Storb 《Biology of blood and marrow transplantation》2004,10(5):320-327
The reported incidence of grades II to IV acute graft-versus-host disease (GVHD) after hematopoietic cell transplantation with HLA-identical sibling donors has increased considerably during the past 15 to 20 years at our center. The purpose of this study was to evaluate the potential reasons for this change. We reviewed organ stages and overall grades of GVHD for 2220 patients who received a first marrow or peripheral blood cell transplant from an HLA-identical sibling or an HLA-allele-matched unrelated donor with the use of a posttransplantation immunosuppressive regimen that included both methotrexate and cyclosporine between 1985 and 2001. The most striking change was an increased incidence of stage 1 gut involvement from 10% to 20% before 1992 to 50% to 60% since 1992, both with related and unrelated donors. This change increased the incidence of grade II GVHD with sibling donors, such that the overall incidence of grade II to IV GVHD is now 60% to 70%. Among patients with chronic myeloid leukemia in chronic phase, the increasingly frequent diagnosis of acute GVHD since 1992 has not been associated with decreased survival. A high diagnostic sensitivity and increased awareness that gut GVHD can occur without skin involvement account for the increased incidence of acute GVHD at our center. 相似文献
79.
Pathogenesis of endometritis and salpingitis in a guinea pig model of chlamydial genital infection. 下载免费PDF全文
The development of tubal obstruction and subsequent infertility is a major sequelum of upper genital tract infection with Chlamydia trachomatis; however, little is known about the pathogenesis of the infection. In this investigation, the authors present a detailed study of the progression of ascending chlamydial infection in female guinea pigs resulting from intravaginal inoculation of the Chlamydia psittaci agent of guinea pig inclusion conjunctivitis (GPIC). Isolation of chlamydiae from different tissues of the genital tract revealed definitive evidence for ascending infection that was not dose-related. By 7 days after infection, GPIC was isolated from the endometrium and oviducts of 78% of the animals. Pathologic changes analogous to those seen in human chlamydial disease, including polymorphonuclear, mononuclear, and plasma cell infiltration, were seen in the endometrium and oviducts, although not all isolation positive animals developed overt tubal disease. Long-term fibrosis, often in combination with hydrosalpinx, was noted in the mesosalpingeal tissue in 20% of the animals. Thus, the guinea pig:GPIC system represents a model for ascending chlamydial infection resulting from vaginal inoculation of normal guinea pigs that closely approximates the disease as seen in humans and can be used to study the pathogenesis of chlamydial genital infection. 相似文献
80.
Genetics of rheumatoid arthritis 总被引:4,自引:0,他引:4
H. Payami G. Thomson M. A. Khan D. M. Grennan P. Sanders P. Dyer C. Dostal 《Tissue antigens》1986,27(2):57-63
The haplotype sharing distribution in affected sib pairs are used to demonstrate the linkage of a susceptibility gene for rheumatoid arthritis (RA) to the HLA region. Family and population studies suggest heterogeneity in the etiology of RA. 相似文献