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41.
Recent studies suggest that the progesterone receptor isoforms (PR-A and PR-B) activate genes differentially and that PR-A may act as a repressor of PR-B function. Hence, the absolute and relative expression of the two isoforms will determine the response to progesterone. We have measured their relative expression in the uterus of cycling women who underwent endometrial biopsy. PR isoforms were identified on blots of SDS-PAGE gels by reaction with the AB-52 antibody after immunoprecipitation from endometrial extract. Both isoforms were highest in the peri-ovulatory phase, but levels of PR-A were always higher than those of PR-B. The ratio of PR-A to PR-B changed during the menstrual cycle. Between days 2 and 8, PR-B is almost undetectable and the A:B ratio is >10:1. From days 9 to 13, the ratio is about 5:1, and it is about 2:1 between days 14 and 16. Thereafter, PR-B dwindles rapidly and is virtually undetectable at the end of the cycle. In various hypoestrogenic environments, PR-B expression was reduced. However, exogenous estrogens in the follicular phase in the form of oral contraceptives, enhanced PR-B expression. These data support the possibility that progesterone acts through cycle-specific PR isoforms. 相似文献
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BT Holt NL Parks GA Engh JM Lawrence 《Canadian Metallurgical Quarterly》1997,20(12):1121-4; discussion 1124-5
One hundred thirty-six primary total knee arthroplasty patients were randomized for the use of closed-suction, nonreinfusable wound drains. Blood loss was identical in the drained and undrained groups. Forty percent of undrained wounds compared with 0% of drained wounds required dressing reinforcement. Sixty-nine percent of undrained wounds compared with 39% of drained wounds developed ecchymosis, measuring 92 cm2 in the undrained group and 28 cm2 in the drained group. This study concludes that a simple wound drain effectively minimizes the undesirable accumulation of blood in the surrounding soft tissues and the postoperative wound dressing after total knee arthroplasty. 相似文献
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JL Abkowitz KE Brown RW Wood NL Kovach SW Green NS Young 《Canadian Metallurgical Quarterly》1997,176(1):269-273
Parvovirus B19 (B19) DNA was detected by dot blot hybridization in sera from 5 (17%) of 30 human immunodeficiency virus (HIV)-infected patients with hematocrits (HCT) of < or =24 and 4 (31%) of 13 HRV-infected patients with HCT of < or =20, suggesting that B19 is a reasonably common cause of severe anemia in HIV infection. The anemia promptly remitted after immunoglobulin therapy in 3 of 4 treated patients. The presence of IgM to B19, the clinical circumstance in which anemia developed, and the marrow morphology were poor predictors of chronic B19 infection. DNA hybridization studies of sera from 191 HIV-infected and 117 HIV-seronegative homosexual males attending a clinic in the Seattle area revealed that 1 (0.5%) and 2 (2%) samples, respectively, from the 2 groups contained B19. However, when assayed by polymerase chain reaction (PCR), 5% of the serum samples from HIV-infected persons and 9% from uninfected persons contained B19, although each had an HCT of > or =40. The data argue that anemia results from chronic high-titer B19 infection. Although a negative PCR assay excludes this diagnosis, DNA hybridization may be the more specific serum test. 相似文献
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RD Bloebaum NL Mihalopoulus JW Jensen LD Dorr 《Canadian Metallurgical Quarterly》1997,79(7):1013-1022
Microradiography, backscattered electron microscopy, and histological analysis were used to conduct a quantitative postmortem study of seven consecutively retrieved anatomical porous replacement acetabular components that had been inserted during total hip arthroplasties. Screws had been used for the initial fixation of six components. The microradiographic analysis of all seven components showed that an average (and standard deviation) of 84 +/- 9 per cent (range, 72 to 93 per cent) of the porous coating was in direct apposition to the periprosthetic bone. The backscattered electron images demonstrated that an average of 12 +/- 6 per cent (range, 4 to 21 per cent) of the space available in the porous coating was occupied by ingrown bone. The amount of bone ingrowth was not significantly different among the three zones delineated by DeLee and Charnley. Uniformity of bone growth into the porous coating suggests that the preferential loading that occurs in the superior region did not differentially affect the bone ingrowth. The present study showed that consistent bone growth into anatomical porous replacement acetabular components can be achieved. 相似文献
47.
JR Mayo M Remy-Jardin NL Müller J Remy DF Worsley C Hossein-Foucher JS Kwong MJ Brown 《Canadian Metallurgical Quarterly》1997,205(2):447-452
PURPOSE: To compare prospectively the accuracy of spiral computed tomography (CT) with that of ventilation-perfusion scintigraphy for diagnosing pulmonary embolism. MATERIALS AND METHODS: Within 48 hours of presentation, 142 patients suspected of having pulmonary embolism underwent spiral CT, scintigraphy, and (when indicated) pulmonary angiography. Pulmonary angiography was attempted if interpretations of spiral CT scans and of scintigrams were discordant or indeterminate and intermediate-probability, respectively. RESULTS: In the 139 patients who completed the study, interpretations of spiral CT scans and of scintigrams were concordant in 103 patients (29 with embolism, 74 without). In 20 patients, intermediate-probability scintigrams were interpreted (six with embolism at angiography, 14 without); diagnosis with spiral CT was correct in 16. Interpretations of spiral CT scans and those of scintigrams were discordant in 12 cases; diagnosis with spiral CT was correct in 11 cases and that with scintigraphy was correct in one. Spiral CT and scintigraphic scans of four patients with embolism did not show embolism. Sensitivities, specificities, and kappa values with spiral CT and scintigraphy were 87%, 95%, and 0.85 and 65%, 94%, and 0.61, respectively. CONCLUSION: In cases of pulmonary embolism, sensitivity of spiral CT is greater than that of scintigraphy. Interobserver agreement is better with spiral CT. 相似文献
48.
A stereoselective reversed-phase liquid chromatographic method for the determination of compounds LY300502 and LY300503 (enantiomers of LY191704) in rat and dog plasma was developed. The assay involved extraction of the compounds using a strong cation-exchange solid-phase extraction column, from which the compounds are eluted with 1% of 1 M HCI in methanol. The enantiomers were separated on a Daicel Chiralcel OD-R column. The mobile phase consisted of water-acetonitrile-methanol (50:40:10, v/v) at a flow-rate of 0.3 ml/min. UV detection was achieved at 220 nm. The disposition of the enantiomers of LY191704 in rats and dogs was found to be stereoselective and species specific. 相似文献
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