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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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Coagulation screening before epidural analgesia in pre-eclampsia   总被引:1,自引:0,他引:1  
A questionnaire survey of current practice at a small cross-section of obstetric units, covering 22% of all United Kingdom deliveries, revealed a marked lack of standard practice regarding requests for coagulation screens on pre-eclamptic patients who require epidural procedures. A retrospective audit was therefore carried out on 434 coagulation screens requested for pre-eclamptic patients in whom epidural analgesia might have been considered. Borderline abnormalities of coagulation were found in only 10 patients (2%). Platelet counts of less than 150 x 10(9)/litre were present in 28% of cases. 'Significant' thrombocytopenia (less than 100 x 10(9)/litre) and all coagulation abnormalities were only encountered in severe pre-eclampsia (diastolic blood pressure of greater than 110 mmHg and proteinuria of + + or greater). Furthermore, coagulation abnormality was always associated with a reduced platelet count (mean, 97 x 10(9)/litre). This study would therefore support anaesthetic practice which restricted any requests for coagulation testing to severe pre-eclamptic patients only. For these patients first line testing could be limited to a platelet count.  相似文献   
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Urinary tract injuries during obstetric intervention   总被引:11,自引:0,他引:11  
A retrospective case record review of obstetric urinary tract injury in the Grampian region from 1976 to 1993 identified 16 cases of bladder injury (0.1 per 1000 deliveries, 1.4 per 1000 caesarean sections and four cases of ureteric injury (0.03 per 1000 deliveries, 0.27 per 1000 caesarean sections). Diagnosis of bladder injury was immediate, but of ureteric injury often delayed. Although the injury rates are lower than previously reported and previously reported risk factors not confirmed, this audit has resulted in guidelines for junior staff, compliance with which will be monitored, and every case of urinary tract injury will be reviewed.  相似文献   
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Oligohydramnios-polyhydramnios sequence in twin pregnancies may be managed by aggressive amniocentesis and is described in nine consecutive cases. In four of the nine pregnancies both twins survived, one pair died in the neonatal period, and the other four pairs all suffered intrauterine death. The median number of amnioreductions performed was five (range 2–7). In this series the reaccumulation of urine in the bladder of the 'stuck twin' was a predictive prognostic marker of survival in both twins, with a sensitivity and specificity of 100%.  相似文献   
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