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D Van Neste† RM Trüeb‡ 《Journal of the European Academy of Dermatology and Venereology》2006,20(5):578-583
BACKGROUND: Computer-assisted image analysis has been proposed for human hair growth studies. METHODS: The performances of Trichoscan, a commercially available automated system combining epiluminiscence microscopy with digital image analysis, developed for office-based hair growth measurements, have been evaluated comparatively on the same skin sites using standardized photographic equipment and calibrated processing for contrast-enhanced phototrichogram (CE-PTG) analysis. This reference method has been validated with scalp biopsies and histological examination of serial sectioning. RESULTS: Besides edge effects, hair fibres escaped the Trichoscan analysis for various reasons including, but not limited to, thickness, pigmentation, closeness and crossing. CONCLUSION: Most of these problems have been identified in the late 1980s and remain largely unsolved by the processing software that was evaluated in 2004. Therefore claims promoting the Trichoscan method for accurate hair measurements in clinical trials on scalp and body hair are not supported by the present investigation. The speed at which the analysis is performed is outweighed by the errors in signal detection. Therefore we suggest that improvements must be clearly documented before Trichoscan is established for quantified diagnostic purposes and detailed hair cycle monitoring during hair trials. 相似文献
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L D Nord R C Willis T S Breen T L Avery R A Finch Y S Sanghvi G R Revankar R K Robins 《Biochemical pharmacology》1989,38(20):3543-3549
The basis for the antitumor activities of the exocyclic amino nucleosides 4-amino-(ARPP) and 4-methoxy-8-(D-ribofuranosylamino)pyrimido[5,4-d]pyrimidine (MRPP) was investigated. The primary target of these nucleosides appeared to be 5-phospho-alpha-D-ribofuranose-1-pyrophosphate (PRPP) synthetase. MRPP-5'-monophosphate was a competitive inhibitor (Ki = 40 microM) of the activation of this enzyme by the cofactor inorganic phosphate (K alpha = 2.2 mM). Consequently, ARPP and MRPP treatment of WI-L2 cultures rapidly inhibited both de novo pyrimidine and purine synthesis as well as the nucleotide salvage reactions dependent on PRPP, ARPP or MRPP treatment completely prevented [14C]bicarbonate incorporation into acid-soluble pyrimidine and purine nucleotides. The rate of salvage of [8-14C]hypoxanthine to form IMP was decreased by 85%. Treatment of cells with these agents caused a 50% reduction in the steady-state level of PRPP. When the capacity of the treated cells for sustained synthesis of PRPP was examined by adenine incorporation, the rate of adenine uptake was inhibited by greater than 50%. In vivo treatment of BDF1 mice with a single dose of ARPP (173 mg/kg) or MRPP (62 mg/kg) extended the mean life span of the mice, which had been inoculated intraperitoneally 1 day earlier with 1 x 10(6) L1210 murine leukemia cells, by 62 and 82% respectively. These studies indicate that MRPP and ARPP inhibit PRPP synthetase, and that PRPP synthetase may be a viable target in the development of certain antitumor agents. 相似文献
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Nonvoluntary sexual activity among adolescents 总被引:3,自引:0,他引:3
Data from the 1987 round of the National Survey of Children indicate that seven percent of Americans aged 18-22 have experienced at least one episode of nonvoluntary sexual intercourse. Women were more likely than men to report having had such an experience, with just under half of all nonvoluntary experiences among women occurring before the age of 14. Multiple classification analysis reveals that white women who had lived apart from their parents before age 16, those who had been brought up in poverty, those who had had a physical, emotional or mental limitation when they were young, those whose parents had been heavy drinkers, those whose parents had used illegal drugs and those whose parents had smoked cigarettes when they themselves were teenagers were at significantly greater risk for experiencing sexual abuse. Six percent of young white women with no risk factors, nine percent of those with one, 26 percent of those with two, and 68 percent of those with three or more had been sexually abused before or during adolescence. 相似文献
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V Schleyer† S Radakovic-Fijan‡ S Karrer† T Zwingers§ A Tanew‡ M Landthaler† RM Szeimies† 《Journal of the European Academy of Dermatology and Venereology》2006,20(7):823-828
BACKGROUND: Based on good results in the treatment of superficial skin tumours, since the early 1990s topical photodynamic therapy with aminolaevulinic acid (ALA PDT) has been used for disseminated, inflammatory dermatoses including psoriasis. However, there is still a lack of well-documented trials. OBJECTIVE: A prospective randomized, double-blind phase I/II intrapatient comparison study was conducted in 12 patients to investigate whether topical ALA PDT is an effective treatment for chronic plaque-type psoriasis. METHODS: In each patient three psoriatic plaques were randomly treated with a light dose of 20 J/cm(2) and 0.1%, 1% and 5% ALA, respectively. Treatment was conducted twice a week until complete clearance or for a maximum of 12 irradiations. Therapeutic efficacy was assessed by weekly determination of the psoriasis severity index (PSI). RESULTS: The mean percentage improvement was 37.5%, 45.6% and 51.2% in the 0.1%, 1% and 5% ALA-treated groups, respectively. Irradiation had to be interrupted several times because of severe burning and pain sensation. CONCLUSION: Topical ALA PDT did not prove to be an appropriate treatment option for plaque-type psoriasis due to disappointing clinical efficacy, the time-consuming treatment procedure and its unfavourable adverse event profile. 相似文献
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The effect of three beta-lactamase inhibitors, clavulanic acid, sulbactam and tazobactam used in clinical practice were compared for their activity against purified beta-lactamases from Bacteroides uniformis, Clostridium butyricum and Fusobacterium nucleatum. The enzymes from B. uniformis and C. butyricum were produced in fermenters under controlled growth conditions and the enzyme from F. nucleatum was produced in batch cultures. Purification of the beta-lactamases was achieved by anion-exchange chromatography, gel filtration and FPLC-technique. The degree of inactivation of beta-lactamase activity was determined spectrophotometrically with nitrocefin as the substrate. The inhibitors in various concentrations were preincubated at 30 degrees C together with the enzyme for different time periods (0.5-120 min) before determination of the remaining beta-lactamase activity. The inhibitors all decreased the activity of the beta-lactamases investigated. Clavulanic acid and sulbactam were capable of reducing the enzyme activity of the B. uniformis beta-lactamase more effectively than the C. butyricum and F. nucleatum beta-lactamases. All beta-lactamases tested were more susceptible to tazobactam than to clavulanic acid and sulbactam. 相似文献
10.
M.M. Bialoskurski MA RN RM C.L. Cox MSc PhD RN & R.D. Wiggins PhD 《Journal of advanced nursing》2002,37(1):62-69
AIM: The aim of this study was to investigate the nature and organization of maternal needs and priorities in a neonatal unit. BACKGROUND: The relationship between maternal needs and priorities appears to be an under studied area in neonatal nursing. METHODS: A quantitative survey was carried out based on 209 mothers with premature infants. Two self-assessment schedules were used: critical care maternal needs inventory (J. Leske, Heart and Lung 15, 27-42) and a ranking scale. The data were analysed with multivariate analysis. FINDINGS: Data analysis revealed clear priorities in maternal needs. In particular the need for accurate infant related information was a priority for 93% of the mothers. Good communication practices with professionals were also valued. The mothers displayed altruistic behaviour, and self-related needs took second place. It is proposed that maternal needs demonstrate a hierarchical organization. CONCLUSION: It is important for nurses to consider the individual needs of the mothers, simply because the satisfaction of these needs is essential for maternal well-being. 相似文献