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41.
Based on a retrospective analysis of a group of patients with ileus disease in regard of the indication for operative intervention an "ileus index" was created which is derived from simple clinical and radiological findings and laboratory data. Prospective evaluation of this index showed its effectiveness in separating patients who had to undergo an emergency operation from those who could be operated electively after preceding diagnostic procedures or could be treated conservatively. 相似文献
42.
Amorphous hydrogenated carbon (a-C:H) films have many outstanding properties required for a protective coating material on load bearing medical implants. Recently, titanium doped a-C:H films have been evaluated regarding their effects on bone marrow cell cultures. But many materials that are well-tolerated in bulk form are able to induce toxic reaction if present particulate form. In order to further assess biocompatibility aspects of these two coatings, film delamination has been mimicked in exposure to fluids. In the present study, particles from a-C:H, a-C:H/Ti and a-C:H-a-C:H/Ti bilayer films were added to bone marrow cell cultures in vitro. The results showed that plain a-C:H and to a certain extent a-CH/Ti particles were inert. Both kinds of particles did not significantly stimulate the osteoclast-related enzyme tartrate resistant acid phosphatase (TRAP). A slight increase in cell proliferation and total culture TRAP was found in cultures treated by a-C:H-a-C:H/Ti bilayer films. Latter effect can probably be traced back by the relative high percentage of small particles of a size of around 2 microm. However, if corrected by the cell number also no differences between particle-treated and untreated control cultures could be found, indicating the absence of a toxic effect from delaminated a-C:H coatings. 相似文献
43.
M L Hansmann E Deltz M Gundlach P Schroeder H J Radzun 《American journal of clinical pathology》1989,92(5):686-692
A small bowel transplant was performed on a five-year-old boy with a short bowel syndrome. The donor was the child's mother. Despite immunosuppressive therapy, the transplant was acutely rejected and had to be explanted on the twelfth day. Morphologic and immunohistochemical investigations on subsequent biopsies taken from the small bowel transplant were carried out. Besides typical changes in epithelial cells and the presence of T-cell infiltrates and Ig-deposits in vessels, many macrophages were seen. The submucosa in particular was invaded before rejection by numerous macrophages with positive results of antimonocyte/macrophage antibodies Ki-M6 and Ki-M7. The number of the macrophage antibodies Ki-M6 and Ki-M7. The number of the monocyte/macrophage cells and the immunohistochemical characteristics of the same may be important parameters for monitoring small bowel transplantations. 相似文献
44.
Meisel P Krause T Cascorbi I Schroeder W Herrmann F John U Kocher T 《Genes and immunity》2002,3(2):102-106
Myeloperoxidase (MPO) is an oxidative enzyme expressed in polymorphonuclear leukocytes. It is involved in the defence against periodontal bacteria, and is also able to mediate inflammatory tissue destruction in periodontal disease. A G/A polymorphism in the promoter region of the MPO gene at position -463 has been assumed to exert profound effects on the expression of the enzyme. It is the aim of this study to evaluate whether this polymorphism may influence the risk of periodontal diseases. A total of 3148 subjects were randomly selected from the general population in the SHIP study (Study of Health in Pomerania). Periodontal status, health-related and socio-economic items were assessed. All subjects aged 40-60 years (n = 1103) were included in this study, and 1083 genotyped for the MPO -463 G/A polymorphism by PCR and RFLP methods. The genotype frequencies determined were homozygous wild type G/G 65.9% (95% CI 63.5-68.6), heterozygous A/G 31.4% (28.8-34.4), and homozygous variant A/A 2.7% (2.0-3.8). Only female subjects have a significantly reduced risk of severe periodontal disease when bearing the variant genotypes A/G or A/A. In female subjects the reduction in periodontal risk was significant for non-smokers (OR = 0.48; 95% CI 0.23-0.96); the smoke-related increase in risk was also reduced (OR = 0.50; 95% CI 0.22-1.10). When adjusted for age, smoking, and education the odds ratios were calculated as 0.52 (P = 0.01) and 0.97 (P = 0.90) for female and male subjects, respectively. The results of this study confirm the assumption that the MPO -463A allele variants are protective in the pathogenesis of periodontal diseases. This holds true only with women but not with men. The results are discussed with respect to the known influences of sexual hormones on MPO activity. 相似文献
45.
46.
TT-virus (TTV, patient initials: T.T.), a novel DNA virus, was first isolated in Japan in 1997 from serum of a patient with post-transfusion hepatitis of unknown aetiology. To date, the contribution of TTV to liver disease remains doubtful. The potential for transmission via blood and blood products makes it essential to establish the prevalence of TTV viraemia in the blood donor population. 413 blood donor serum samples were chosen randomly, the DNA was extracted and TTV-specific DNA amplified by nested polymerase chain reaction (PCR). TTV infection was present in 13 out of 413 (3.15%) blood donors in the Auckland region of New Zealand using a set of primers targeting open reading frame (ORF) 1. These 13 amplification products (264 bp) were sequenced and TTV genotypes determined. Alignment with published TTV sequences showed that seven (53.8%) of the thirteen positive serum samples belonged to genotype 1, five (38.5%) belonged to genotype 2 and one (7.7%) could not be classified as either genotype 1 or 2. One hundred twenty-seven blood donor serum samples were retested with a second set of primers targeting the 5' region of the TTV genome in a single round PCR. Forty-three samples were positive for TTV DNA with these primers resulting in a prevalence of 37%. The data demonstrate that TTV is present among New Zealand blood donors and support the need for further investigation into the natural history of TTV infection. 相似文献
47.
Hall GS Gordon S Schroeder S Smith K Anthony K Procop GW 《Journal of clinical microbiology》2001,39(3):1202-1203
We report a case of synovitis in a 64-year-old man who developed the infection while on steroid therapy for rheumatoid arthritis. Dolosigranulum pigrum, a gram-positive catalase-negative coccus, was isolated from two sets of blood cultures prior to antibiotic therapy. The patient was treated with 4 weeks of appropriate antibiotics, and the synovial inflammation resolved. Although synovial aspirates were never positive for any bacteria or fungi, the timing of positive blood cultures and absence of other pathogens suggest the possible etiology as D. pigrum. 相似文献
48.
49.
Summary Neutral red (NR)-labeled influenza virus is extremely photosensitive. Unlike NR-labeled picornaviruses which lose their photosensitivity only after penetrating the host cell, NR-labeled influenza virus loses most of its photosensitivity during adsorption at 4°C. We demonstrate that the underlying reaction occurs within seconds of adsorption and that it is irreversible, i.e., NR virus eluted from chick embryo cells after adsorption is hardly photosensitive anymore. In contrast to this, NR virus adsorbed to and eluted from erythrocytes retains its original photosensitivity. We suggest that the loss of photosensitivity during adsorption of NR virus to host cells reflects a conformational change in the virion which is not elicited by adsorption to red blood cells. 相似文献
50.
Use of subgenic 18S ribosomal DNA PCR and sequencing for genus and genotype identification of acanthamoebae from humans with keratitis and from sewage sludge 总被引:11,自引:0,他引:11 下载免费PDF全文
Schroeder JM Booton GC Hay J Niszl IA Seal DV Markus MB Fuerst PA Byers TJ 《Journal of clinical microbiology》2001,39(5):1903-1911
This study identified subgenic PCR amplimers from 18S rDNA that were (i) highly specific for the genus Acanthamoeba, (ii) obtainable from all known genotypes, and (iii) useful for identification of individual genotypes. A 423- to 551-bp Acanthamoeba-specific amplimer ASA.S1 obtained with primers JDP1 and JDP2 was the most reliable for purposes i and ii. A variable region within this amplimer also identified genotype clusters, but purpose iii was best achieved with sequencing of the genotype-specific amplimer GTSA.B1. Because this amplimer could be obtained from any eukaryote, axenic Acanthamoeba cultures were required for its study. GTSA.B1, produced with primers CRN5 and 1137, extended between reference bp 1 and 1475. Genotypic identification relied on three segments: bp 178 to 355, 705 to 926, and 1175 to 1379. ASA.S1 was obtained from single amoeba, from cultures of all known 18S rDNA genotypes, and from corneal scrapings of Scottish patients with suspected Acanthamoeba keratitis (AK). The AK PCR findings were consistent with culture results for 11 of 15 culture-positive specimens and detected Acanthamoeba in one of nine culture-negative specimens. ASA.S1 sequences were examined for 6 of the 11 culture-positive isolates and were most closely associated with genotypic cluster T3-T4-T11. A similar distance analysis using GTSA.B1 sequences identified nine South African AK-associated isolates as genotype T4 and three isolates from sewage sludge as genotype T5. Our results demonstrate the usefulness of 18S ribosomal DNA PCR amplimers ASA.S1 and GTSA.B1 for Acanthamoeba-specific detection and reliable genotyping, respectively, and provide further evidence that T4 is the predominant genotype in AK. 相似文献