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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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Transplantation of microencapsulated bovine chromaffin cells reduces lesion-induced rotational asymmetry in rats 总被引:7,自引:0,他引:7
Surrounding bovine chromaffin cells by a semipermeable membrane may protect the transplanted cells from a host immune response and shield them from the inflammatory process resulting from the surgical trauma. Encapsulation of the chromaffin cells was achieved by inter-facial adsorption of a polycation on a polyanionic colloid matrix in which the chromaffin cells were entrapped. Basal and potassium-evoked release of catecholamines from encapsulated bovine chromaffin cells was analyzed over a 4-week period in vitro. Norepinephrine and dopamine release remained constant over time whereas epinephrine release significantly decreased. The chromaffin cells also retained the capacity for depolarization-elicited catecholamine release 4 weeks following the encapsulation procedure. Morphological analysis revealed the presence of intact chromaffin cells with well-preserved secretory granules. Striatial implantation of chromaffin cell-loaded capsules significantly reduced apomorphine-induced rotation compared to empty polymer capsules in animals lesioned with 6-hydroxydopamne frr at least 4 weeks. Intact chromaffin cells expressing tyrosine hydroxylase and dopamine-β-hydroxylase were observed in all capsules implanted in the striatum for 4 weeks. The assessment of the clinical potential of transplanting encapsulated adrenal chromaffin cells of either allo- or xenogeneic origin for Parkinson's disease will require long-term behavioral studies. The present study suggests, however, that the polymer encapsulation procedure may offer an alternative to adrenal autografts as a source of dopaminergic tissue. 相似文献
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Adenosine release and changes in pial arteriolar diameter during transient cerebral ischemia and reperfusion 总被引:1,自引:0,他引:1
J R Meno A C Ngai S Ibayashi H R Winn 《Journal of cerebral blood flow and metabolism》1991,11(6):986-993
We utilized the closed cranial window technique in the anesthetized rat to determine changes in CSF concentrations of adenosine, inosine, and hypoxanthine and pial arteriolar diameter during transient (20 min) forebrain ischemia and reperfusion. After mock CSF under the cranial window was allowed to equilibrate with cerebral interstitial fluid, endogenous adenosine concentration was found to be 0.16 +/- 0.05 microM, while inosine and hypoxanthine were 0.35 +/- 0.17 and 1.23 +/- 0.47 microM, respectively. The concentration of adenosine in CSF increased 4.2-fold during ischemia and 13.8-fold during the first 5 min of reperfusion. Inosine and hypoxanthine concentrations were also significantly increased during ischemia and reperfusion. After 1 h of reperfusion, CSF adenosine and inosine levels had decreased from peak value but remained significantly above preischemic values. In contrast, hypoxanthine remained at peak concentrations even after 60 min of reperfusion. Preischemic arteriolar diameter was 42.6 +/- 11.3 microns and was not significantly changed after 20 min of ischemia. However, during the first 5 min of reperfusion, arteriolar diameter increased significantly (p less than 0.05), coincident with peak adenosine concentrations. By 60 min of reperfusion, arteriolar diameter had returned to baseline. These results indicate that during the postischemic period, adenine nucleosides and hypoxanthine in CSF are elevated and could affect reperfusion. 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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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