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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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Haiyung Cheng Jules I. Schwartz Charles Lin Raju D. Amin James R. Seibold Kenneth C. Lasseter David L. Ebel Dominick J. Tocco J. Douglas Rogers 《Biopharmaceutics & drug disposition》1994,15(5):409-418
MK-679 (R(?)-3-((3-(2-(7-chloro-2-quinolinyl)ethenyl)phenyl)(3-(dimethylamino)-3-oxopropyl)thio)methyl)thio(propanoic acid) is a potent and specific LTD4-receptor antagonist. The disposition of MK-679 was investigated in a three-way crossover study in 12 healthy males receiving single intravenous doses of 75, 250, and 500 mg of MK-679. A greater than proportional increase in the area under the plasma concentration—time curve of MK-679 was observed with increase in dose. The plasma concentration data for each subject fitted well to the differential equations for a two-compartment model with linear tissue distribution and Michaelis-Menten elimination from the central compartment, indicating that the elimination of MK-679 in humans is saturable. In a previous study, the disposition of MK-679 in humans was also dose-dependent when given together with its S(+)-isomer, L-668,018. Thus, the disposition of MK-679 in humans is dose-dependent regardless of the presence of its stereoisomer. Also, the bioavailability of MK-679 was determined in six healthy males receiving simultaneously an oral dose of 250 mg of MK-679 and intravenous infusion of 1 mg 14C-MK-679. Results of this study indicate that the oral bioavailability of MK-679 is nearly quantitative. 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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Sajja Lokeswara Rao Mannam Gopichand Sompali Sriramulu Reddy Karri Venkata Ravirala Bala Raju Raju Bhupathiraju Soma Raju Penmetcha Krishnam 《Indian Journal of Thoracic and Cardiovascular Surgery》2004,20(4):173-177
Background Cardiopulmonary bypass (CPB) may contribute to the complications and it is assumed that eliminating cardiopulmonary bypass
has the potential of reducing post operative morbidity after coronary artery bypass grafting (CABG). The study was carried
out to compare mortality and morbidity in the off-pump and on-pump CABG groups.
Methods We prospectively analysed 200 patients undergoing CABG. Group A consists of 100 patients underwent multi-vessel off-pump CABG
and group B consists of 100 patients underwent CABG with CPB. The incidence of complications (mortality, re-exploration for
bleeding, myocardial infarction, atrial fibrillation, neurological events, new onset renal failure (s. creatinine>1.6 mg/dL)
pulmonary complications, length of ICU stay and hospital stay were recorded, analysed and compared.
Results OPCAB patients received 2.73±0.61 grafts/patient and on-pump CABG patients received 3.39±0.75 grafts/patient (p value<0.00001). There was no significant statistical difference in mortality, incidence of stroke between OPCAB and CABG
with CPB patients. Length of ICU stay was 32.84±4.22 vs 44.85±7.18 hrs (p value<0.00001) and hospital stay was 6.52±0.69 vs 7.94±0.92 days (p value<0.00001) between group A and group B respectively. Incidence of atrial fibrillation was less in OPCAB group 7% vs 12%
although it was statistically not significant (p value 0.33). It was observed in our study that there was no significant deference in worsening of existing renal failure
between on-pump CABG and OPCAB 6% vs 2% (P value 0.28). Blood utilization was significantly less in OPCAB group (p value<0.001).
Conclusion There was no statistically significant difference in terms of mortality, incidence of stroke and new onset renal failure in
both groups. But there was lesser incidence of post operative atrial fibrillation, worsening of existing renal failure in
off-pump group though statistically not significant. There was significant reduction in blood utilization, length of ICU and
hospital stay in OPCAB group. 相似文献
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Seventy patients with abnormal vaginal bleeding were examined with a Storz hysteroscope. The examination took an average of only 5 min. Sixty patients had the examination under general anaesthesia, five under paracervical block and five had no form of anaesthesia. All tolerated the procedure well. There were no complications directly related to the hysteroscopic examination. There was complete correlation between the histology of the endometrium obtained at subsequent curettage and the hysteroscopic findings. 相似文献