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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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E R Wald 《The Journal of family practice》1988,26(4):367-368
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Studies were performed to evaluate the effect of unilateral nephrectomy on glycerol-induced acute renal failure in the rat. Normal rats were subjected to either sham uninephrectomy (n = 43) or right uninephrectomy (n = 53). The functional compensation of the remaining kidney was followed after 1 and 2 weeks. Fourteen days after the operation, acute renal failure was induced by injection of 50% glycerol solution to both groups. Uninephrectomised rats developed a lesser degree of renal failure compared to sham-operated rats. Forty-eight hours after glycerol injection, PCr of uninephrectomised rats was 260 +/- 22 mumol/l compared with 338 +/- 26 in sham-operated rats (P less than 0.0125) and CCr in uninephrectomised rats was greater (0.10 +/- 0.01 ml/min vs 0.07 +/- 0.01; P less than 0.025) in sham rats. Uninephrectomised rats had significantly greater recovery of CCr compared to sham rats at 24 h (20.1% +/- 2.3 vs 13.1% +/- 2.2, P less than 0.025) and at 48 h (32.1% +/- 3.3 vs 19.2% +/- 3.3, P less than 0.005) after glycerol injection. FENa was significantly less in uninephrectomised rats: 0.96 +/- 0.16% vs 2.25 +/- 0.05% (P less than 0.025) in sham rats 24 h post glycerol. Urinary excretion of K+ was greater in rats following uninephrectomy compared to sham rats both after 24 h and 48 h post glycerol (P less than 0.01), accompanied by lower plasma potassium (P less than 0.05). A correlation coefficient (r) of 0.793 was observed between urinary potassium excretion rate and percentage recovery of CCr.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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To further characterize changes in tubular Na-K-ATPase in acute tubular necrosis (ATN), segmental analysis was performed in rat nephrons. Na-K-ATPase was assayed in the following segments: proximal convolution (PC), proximal straight (PS), outer medullary thick ascending limb (MTAL), cortical thick ascending limb (CTAL), distal convolution (DC) and cortical collecting duct (CCD) in three groups of rats: 1.) intact; 2.) moderate non-oliguric ATN; and 3.) severe oliguric ATN. GFR and CNa/GFR X 100 were in group 1 0.80 +/- 0.05 ml/min and 0.68 +/- 0.06, in group 2 0.14 +/- 0.02 and 1.46 +/- 0.35, and in group 3 0.04 +/- 0.01 and 0.46 +/- 0.15, respectively. Na-K-ATPase in PC and PS were similar in all three groups. Na-K-ATPase levels were in MTAL: in group 1 37 +/- 2 X 10(-11) mol/mm/min, in group 2 20 +/- 1 X 10(-11), P less than 0.001 versus group 1, and in group 3 24 +/- 2 X 10(-11), P less than 0.001 versus group 1. In CTAL Na-K-ATPase levels were: in group 1 40 +/- 2 X 10(-11), in group 2 33 +/- 1 X 10(-11), P less than 0.001 versus group 1, and in group 3 27 +/- 2 X 10(-11), P less than 0.001 versus groups 1 and 2.(ABSTRACT TRUNCATED AT 250 WORDS) 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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