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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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双波长紫外分光光度法测定贝母中腺苷和胸苷的含量   总被引:4,自引:0,他引:4  
将4种贝母的甲醇提取物经薄层色谱法粗分离后,直接用双波长紫外分光光度法测定其含量。结果表明,该方法线性关系好,腺苷和胸苷标准曲线的相关系数均为0.9999,同时也发现平贝、炉贝和伊贝中腺苷都占核苷总量60%以上,而浙贝中仅占约40%,提示贝母生药的抗凝血活性可能与贝母中核苷类化合物的种类和含量的差别有关。  相似文献   
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We used vitreous surgery to remove idiopathic epiretinal membranes from the macular area in 70 consecutive cases. The abnormal tissue was successfully removed in each case. Vision improved postoperatively in 61 eyes (87%), remained unchanged in six eyes (9%), and worsened in three eyes (4%). However, at the time of final examination vision was improved in only 47 eyes (67%), primarily because of the occurrence or progression of nuclear sclerosis, which occurred in 38 of 60 phakic eyes (63%). Four preoperative factors were associated with final visual acuity of 20/60 or better: (1) initial vision of 20/100 or better, (2) shorter preoperative duration of blurred vision, (3) thin epiretinal membrane, and (4) absence of traction retinal detachment.  相似文献   
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BACKGROUND AND PURPOSE: The familial occurrence of intracranial aneurysms and cervical artery dissections has been described in different families and supports the hypothesis that a primary arteriopathy may play a role in the pathogenesis of these disorders. Although the basis for this arteriopathy is generally not believed to be similar among cases of intracranial aneurysms and cervical artery dissections, several similarities exist in the epidemiology of these disorders and a common underlying arterial abnormality may be suspected. SUMMARY OF REPORTS: The medical records of all 175 patients with spontaneous dissections of the cervical arteries who were seen at the Mayo Clinic between 1970 and 1989 were reviewed to identify families in which intracranial aneurysms and cervical dissections coexisted. Three families were identified in which intracranial aneurysms and cervical artery dissections were observed among siblings. These families are described in detail. CONCLUSIONS: The familial occurrence of intracranial aneurysms and cervical artery dissections within the same families provides support to the importance of a common underlying arteriopathy in the pathogenesis of both these disorders. The underlying vascular defect may, at least in some cases, be inherited.  相似文献   
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Clinicopathologic correlation of pigmented epiretinal membranes   总被引:1,自引:0,他引:1  
We performed clinicopathologic correlation on ten surgically removed pigmented epiretinal membranes causing macular pucker. All cases occurred in eyes with existing retinal holes or tears, including eight cases of macular pucker after previous retinal detachment. These cases probably represented a limited form of proliferative vitreoretinopathy. All membranes contained pigment epithelial cells with polarity, basement membrane, and melanosomes. Cytoplasmic melanin granules accounted for the clinical feature of pigmentation in these eyes.  相似文献   
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Zusammenfassung. Ziel: Die psychische Belastung bei Patienten mit akutem Herzinfarkt innerhalb der ersten 48 h auf der Intensivstation des Städtischen Krankenhauses Kiel wird mit Hilfe der Symptom-Checkliste (SCL-90-R) gemessen. Patienten und Methodik: 134 hauptsächlich wegen eines akuten Herzinfarkts aufgenommene Patienten wurden zwischen August 1996 und Juli 1999 randomisiert ausgewählt. Sie füllten einen der Intensivstation angepassten Fragebogen aus, der u. a. neben Fragen zu sozioökonomischen Daten die standardisierten SCL-90-R enthält. Ergebnisse: Erhöhte Mittelwerte zeigten sich vor allem für die Skalen Somatisierung, Ängstlichkeit, Depressivität und GSI (Global Severity Index) bei solchen Patienten, die wenig soziale Unterstützung bekamen und über ein niedriges Einkommen verfügten. Schlussfolgerung: Da für Patienten mit schlechtem sozialen Netzwerk, niedrigem sozialen Status, erhöhter Angst und Depressivität eine schlechtere Prognose hinsichtlich der Mortalität und Wiedereingliederung in den Beruf beschrieben wurde, ist es im prospektiven Verlauf dieser Studie notwendig, gerade diese Patienten hinsichtlich der Entwicklung ihrer Angst zu erfassen und zu behandeln. Abstract. Objective: 134 patients with acute myocardial infarction, who were treated in an intensive care unit (ICU) of a German hospital in Kiel between 1996 and 1999 were selected for the study to examine their psychologic symptoms. Patients and Methods: The patients were asked to fill in the self-report inventory, the Symptom Checklist-90-Revised (SCL-90-R) within the first 48 h after their arrival in the ICU. Results: Patients with a low social status were found to have elevated mean values of the following scales: somatization (0.93), depression (0.66), and anxiety (0.59). The Global Severity Index (GSI) as a global measure of psychologic distress was elevated as well (0.46). Conclusion: Since patients with a limited social network and low social status, increased anxiety and depressive scores have a poor prognosis as to their mortality and their professional reintegration, it it considered necessary for the prospective setting of this study to register particularly those patients in order to treat their anxiety.  相似文献   
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