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41.
OBJECTIVE Recent evidence suggests that androstanediol glucuronide (AG), a metabolite of dihydrotestosterone (DHT) formed in skin, is frequently elevated in hirsute women, presumably reflecting enhanced 5a-reductase activity. An alternative method of demonstrating 5a-reductase activity is the androsterone (A)/aetiocholano-lone (E) ratio in urine. A and E are the 5α- and 5β- reduced metabolites, respectively, of androstenedione, which is the principal metabolite of dehydroepiandrosterone (D). Although serum AG and the urinary A/E ratio have both been considered valid methods for assessing 5α-reductase activity, the two have not been previously compared in hirsute women. The present study was undertaken to assess 5a-reductase activity in hirsute patients as determined by these two different methods. PATIENTS AND MEASUREMENTS We surveyed 47 untreated women (ages 17–33) with various degrees of hirsutism. Serum testosterone, bioavailable testosterone, dehydroepiandrosterone sulphate, and AG were determined. Additionally, A, E and D were measured in 24-hour collections of urine. RESULTS For the 47 women, 37 had elevated blood levels of AG (17.4 ± 2.2, mean±SEM; normal <8 nmol/l), but only 18 of these had an increased urinary A/E ratio (> 1.5). All but one of the remainder had elevated urinary and/or serum androgen levels. Overall, no significant correlation between AG and A/E was observed. There was a highly significant correlation between AG in serum and A in urine (r= 0.82, P<0 001). AG was also positively related to dehydroepiandrosterone sulphate (r= 0.64; P< 0.005), bioavailable testosterone (r= 0.6; P<0001), aetiocholanolone (r= 0.58; P<0 001) and total testosterone (r= 0.52; P& 0.01). In contrast, A/E was not significantly related to androgen production. CONCLUSIONS There is a poor correlation between AG and the A/E ratio in hirsute women. Although AG may be raised by increased 5α-reductase activity, it is probably also affected by the presence of elevated androgens regardless of 5α-reductase activity. 相似文献
42.
The expression of 5T4, an oncotrophoblast cell surface antigen was examined in 72 colorectal and 27 gastric carcinomas, with immunoperoxidase technique, on frozen sections. Highly significant association was found between 5T4 expression in the malignant cells and metastatic spread. The results suggest that the appearance of 5T4 molecules in cancer cells reflects a change which may contribute to the development of metastatic potential. 相似文献
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CA von Arnim R Spoelgen ID Peltan M Deng S Courchesne M Koker T Matsui H Kowa SF Lichtenthaler MC Irizarry BT Hyman 《The Journal of neuroscience》2006,26(39):9913-9922
The beta-amyloid (Abeta) precursor protein (APP) is cleaved sequentially by beta-site of APP-cleaving enzyme (BACE) and gamma-secretase to release the Abeta peptides that accumulate in plaques in Alzheimer's disease (AD). GGA1, a member of the Golgi-localized gamma-ear-containing ARF-binding (GGA) protein family, interacts with BACE and influences its subcellular distribution. We now report that overexpression of GGA1 in cells increased the APP C-terminal fragment resulting from beta-cleavage but surprisingly reduced Abeta. GGA1 confined APP to the Golgi, in which fluorescence resonance energy transfer analyses suggest that the proteins come into close proximity. GGA1 blunted only APP but not notch intracellular domain release. These results suggest that GGA1 prevented APP beta-cleavage products from becoming substrates for gamma-secretase. Direct binding of GGA1 to BACE was not required for these effects, but the integrity of the GAT (GGA1 and TOM) domain of GGA1 was. GGA1 may act as a specific spatial switch influencing APP trafficking and processing, so that APP-GGA1 interactions may have pathophysiological relevance in AD. 相似文献
45.
Treatment with combined IL-2 and alpha-IFN has resulted in synergistic antitumour efficacy in animal studies. The mechanisms responsible for this synergy remain unclear. In this study, several immune parameters which might be involved in mediating antitumour activity have been monitored serially in 15 patients with advanced malignant melanoma or renal cell cancer during treatment with concurrent IL-2 and alpha-IFN. Both drugs were given subcutaneously in low to moderate (outpatient) dosages but for a prolonged duration. This treatment resulted in remarkable immunomodulation. In vivo induction of cytotoxicity against K562 and Daudi target cells was consistently seen, and percentages of peripheral blood cells expressing CD 25 (IL-2 receptor) and CD 56 (Leu-19) increased. In vitro proliferation of lymphocytes in response to IL-2 was enhanced during the treatment periods, whereas spontaneous proliferation was inhibited. Moreover, correlations between immune parameters and subsequent clinical responses were present in the early phase of the study. Cytotoxicity levels generated in vivo as well as the percentage of CD 56+ lymphocytes were higher in patients who responded to treatment than in non-responders. In contrast, responders had lower levels of CD 25+ cells. These findings indicate that it might be possible to select patients who are likely to benefit from prolonged immunotherapy. 相似文献
46.
Axial computed tomographic (CT) scan of the lumbosacral region was performed in 220 patients. The patient population was divided into three groups. The control group included 40 elderly patients without calcification of the ligamenta flava. The second group included 150 patients with posterior protrusion of the intervertebral discs. The third group included 30 patients with spinal stenosis. More than 80% of the patients of the second and the third group had calcification of the ligamenta flava. The diagnostic and practical importance of these findings is discussed. 相似文献
47.
Prematurity Stereotyping by Mothers of Premature Infants 总被引:2,自引:1,他引:1
Previous research has experimentally documented a prematuritystereotype in college students and mothers of full-term infants.The present investigation extends the scope of earlier studiesto mothers of premature infants. Thirty-two mothers of prematureinfants viewed four videotapes of 9-month-old full-term infants,each labeled either full-term or premature and either male orfemale. When infants were labeled premature the mothers perceivedthem as littler, finer featured, weaker, more passive, and slowerthan infants labeled full-term. The mothers also perceived labeledboys as bigger than labeled girls. Differences in stereotypingbetween the mothers in this study and both mothers of full-terminfants and college students are identified and discussed. Resultssuggest that mothers of premature infants expect deficits inpremature infants' physical development but not in prematureinfants' mental or social development. The likely sources andpossible self-fulfilling nature of these biased perceptionsare considered 相似文献
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Christopher G Goetz Stanley Fahn Pablo Martinez-Martin Werner Poewe Cristina Sampaio Glenn T Stebbins Matthew B Stern Barbara C Tilley Richard Dodel Bruno Dubois Robert Holloway Joseph Jankovic Jaime Kulisevsky Anthony E Lang Andrew Lees Sue Leurgans Peter A LeWitt David Nyenhuis C Warren Olanow Olivier Rascol Anette Schrag Jeanne A Teresi Jacobus J Van Hilten Nancy LaPelle 《Movement disorders》2007,22(1):41-47
This article presents the revision process, major innovations, and clinimetric testing program for the Movement Disorder Society (MDS)-sponsored revision of the Unified Parkinson's Disease Rating Scale (UPDRS), known as the MDS-UPDRS. The UPDRS is the most widely used scale for the clinical study of Parkinson's disease (PD). The MDS previously organized a critique of the UPDRS, which cited many strengths, but recommended revision of the scale to accommodate new advances and to resolve problematic areas. An MDS-UPDRS committee prepared the revision using the recommendations of the published critique of the scale. Subcommittees developed new material that was reviewed by the entire committee. A 1-day face-to-face committee meeting was organized to resolve areas of debate and to arrive at a working draft ready for clinimetric testing. The MDS-UPDRS retains the UPDRS structure of four parts with a total summed score, but the parts have been modified to provide a section that integrates nonmotor elements of PD: I, Nonmotor Experiences of Daily Living; II, Motor Experiences of Daily Living; III, Motor Examination; and IV, Motor Complications. All items have five response options with uniform anchors of 0 = normal, 1 = slight, 2 = mild, 3 = moderate, and 4 = severe. Several questions in Part I and all of Part II are written as a patient/caregiver questionnaire, so that the total rater time should remain approximately 30 minutes. Detailed instructions for testing and data acquisition accompany the MDS-UPDRS in order to increase uniform usage. Multiple language editions are planned. A three-part clinimetric program will provide testing of reliability, validity, and responsiveness to interventions. Although the MDS-UPDRS will not be published until it has successfully passed clinimetric testing, explanation of the process, key changes, and clinimetric programs allow clinicians and researchers to understand and participate in the revision process. 相似文献