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41.
Background
Genetic polymorphisms of the TCF7L2 gene are strongly associated with large increments in type 2 diabetes risk in different populations worldwide. In this study, we aimed to confirm the effect of the TCF7L2 polymorphism rs7903146 on diabetes risk in a Brazilian population and to assess the use of this genetic marker in improving diabetes risk prediction in the general population. 相似文献42.
Specificity of a sandwich enzyme-linked immunosorbent assay for detecting Aspergillus galactomannan. 总被引:3,自引:0,他引:3
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C M Swanink J F Meis A J Rijs J P Donnelly P E Verweij 《Journal of clinical microbiology》1997,35(1):257-260
The specificity of a sandwich enzyme-linked immunosorbent assay (ELISA) for detecting Aspergillus galactomannan was tested with exoantigens of 29 fungi cultured from clinical specimens. Cross-reactivity was observed with Penicillium chrysogenum, Penicillium digitatum, and Paecilomyces variotii. Furthermore, 40 serum samples obtained from bacteremic patients with hematologic malignancies were retrospectively tested by sandwich ELISA. False-positive reactions with the serum were reproducible but did not correspond with the results of culture of specific microorganisms. Moreover, the microorganisms cultured from the blood showed no reactivity by the sandwich ELISA. 相似文献
43.
The objective of this study is to determine whether pentachlorophenol (PCP) alters benzo[a]pyrene (B[a]P)-induced DNA adduct formation in infant and adult B6C3F1 male mice. Mice were exposed intraperitoneally to 55 microg B[a]P/g body weight (BW) alone and in combination with several doses of PCP in DMSO. The 32P-postlabeling assay was used to analyze for (+/-) anti-7,8-diol-9,10-epoxide-B[a]P-N(2)deoxyguanosine (BPDE-N(2)G) adducts formed in liver and lung DNA. Hepatic DNA also was analyzed for 8-hydroxy-2'-deoxyguanosine (8-OHdG) base damage in mice exposed to PCP. 8-OHdG was not detected at any dose of PCP in infant or adult mice. PCP exhibited an antagonistic effect on BPDE-N(2)G accumulation in infant mice exposed to B[a]P in combination with 50 microg PCP/g BW at both 12 and 24 hr. Comparatively, BPDE-N(2)G adducts were increased in adult mice exposed to binary mixtures at 24 hr in both hepatic and lung DNA (P < 0.05). Multiple comparison analysis between infant and adult mice revealed that adduct levels in infants exposed to B[a]P alone or in combination with PCP were not different from those observed in adult mice exposed to B[a]P. However, a significant increase in adducts was observed in adult mice exposed to a combination of B[a]P and PCP compared to that in all other treatment groups (P < 0.05). These results suggest that PCP alters the metabolism of B[a]P in both infant and adult mice through different mechanisms, and that infants are not susceptible to the potentiating effects of PCP observed in adult mice. 相似文献
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JE Robb LA Rymaszewski HB Bentley PT Donnan 《Surgical and radiologic anatomy : SRA》1991,13(3):181-185
Summary This study investigated the effect of tilt and observer reliability on radiographic measurements of the position of a prosthetic acetabular cup in seven dry bone pelves using the teardrop as a landmark. Coronal or sagittal tilt of more than five degrees was easily recognisable and there was effectively no observer variation in the measurements up to this limit. In addition, 90 out of 100 randomly selected antero-posterior pelvic radiographs from an outpatient department were not significantly rotated and 93 demonstrated a clearly defined teardrop. Measurements about the teardrop on routine radiographs are therefore sufficiently accurate to allow assessment of prosthetic position.
La valeur du sourcil cotyloidien comme repère d'analyse radiologique
Résumé Cette étude, conduite sur 7 bassins secs, apprécie l'effet de l'inclinaison du bassin sur la qualité de l'analyse radiographique de la position d'une cupule prothétique de hanche en utilisant le sourcil cotyloïdien comme repère. Une inclinaison du bassin dans les plans coronal et sagittal est aisément détectable et il n'existe pas de variation d'analyse entre les différents observateurs en dessous de 5° d'inclinaison. De plus, sur 100 radiographies antéro-postérieures de bassin choisies au hasard dans les dossiers de consultation, 90 avaient été réalisées sans incidence particulièrement adaptée et l'on pouvait repérer facilement le sourcil sur 93% d'entre elles. Les mesures faites sur des radios de routine sont donc suffisamment précises pour permettre l'évaluation de la position d'une prothèse à partir du sourcil cotyloïdien.相似文献
46.
Modification of pancreatic carcinogenesis in the hamster model. 6. The effect of ductal ligation and excision
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The effect of ligation and excision of the pancreatic duct in pancreatic carcinogenesis was examined in the hamster model. Animals were treated with a single dose (20 mg/kg body weight) of N-nitrosobis(2-oxopropyl)amine (BOP) either immediately (Group 1) or on Days 1 (Group 2), 3 (Group 3) or 7 (Group 4) after ligation and excision of the duct of the splenic lobe. Group 5 received BOP shortly after laparoscopy, and Group 6 consisted of BOP-treated controls. All hamsters were killed 46 weeks after BOP treatment. The results showed that despite advanced atrophy of the splenic lobe distal to the excised duct in Groups 1-4, some hamsters in Groups 2, 3, and 4 showed hyperplasia, dysplasia, and increased mitotic activities of ductal and ductular cells. However, carcinomas in the duct-excised atrophic lobe were found only in Groups 1-3. These data indicate that BOP carcinogenesis is mediated through blood circulation, and that cancer development is not inhibited in the duct-excised lobe for up to 3 days after surgery. However, in the entire pancreas, a significant reduction in tumor incidence was seen when the carcinogen was given immediately, or to a lesser extent, 1 day after surgery, regardless of whether or not excision was made. On the contrary, BOP, when given 3 and 7 days after duct excision, enhanced tumor development in the nonexcised (intact) pancreas, compared with other test groups and with BOP controls. Both inhibition and enhancement seemed due to a proportional decrease and increase, respectively, of BOP-responsive cells throughout the intact pancreas. 相似文献
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Lowering the cut off value of an automated chlamydia enzyme immunoassay and confirmation by PCR and direct immunofluorescent antibody test. 总被引:1,自引:0,他引:1
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AIMS: To increase the sensitivity of an automated chlamydia enzyme immunoassay by significantly lowering its cut off value, and to maintain specificity by confirmation with polymerase chain reaction (PCR) and direct immunofluorescent antibody test (DFA). METHODS: Over five months, the cut off value of the enzyme immunoassay used to screen urogenital samples for chlamydia antigen was reduced from 80 to 10. Samples with a test value of 10 or above were further tested with a commercial PCR assay. All samples during the first three months and discrepant samples during the last two months of the study were also tested with the DFA. RESULTS: 3250 urogenital swabs (1246 urethral, 1335 endocervical, 669 pooled urethral/endocervical) from 1246 males and 2004 females were processed. Using the manufacturer's recommended cut off of 80, the enzyme immunoassay identified chlamydia antigen in 134 samples (4.1%). Using the lower cut off value of 10 and either PCR or DFA as the confirmatory test, Chlamydia trachomatis was identified in 178 samples (5.5%). Thus, 45 additional positive samples were identified and the confirmed detection rate was increased by 33.8% (45/133). Excluding equivocal PCR results, the concordance between DFA and PCR was 91.8%. This strategy increased the detection rate by 2.1% in men and 0.9% in women (significant only in men). In female patients, pooled urethral/endocervical swabs as a specimen gave a significantly higher yield than endocervical swabs regardless of whether the lower cut off strategy was used. CONCLUSIONS: This strategy of significantly lowering the cut off test value with confirmation on the same specimen by either PCR or DFA is feasible and cost effective. The use of pooled urethral/ endocervical specimens in females should be considered routinely as detection rate was significantly improved. 相似文献