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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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A Decade of Change in Obesity Surgery   总被引:4,自引:0,他引:4  
Background: The International (formerly National) Bariatric Surgery Registry began collecting data in January 1986. The aim of this study was to examine changes in the practice of surgical treatment of severe obesity that occurred during the decade of 1986 through 1995, as observed in the IBSR data. Methods: All data submitted to the IBSR during the decade were transferred to the IBM mainframe computer for analysis. Characteristics of operative type populations were compared over time using analysis of variance (ANOVA) for age, body mass index (BMI), operative weight and Chi-square (χ2) test for gender. Results: There has been a steady increase over the decade in mean patient weight. The operations used have changed from predominantly ‘simple’ operations to more frequent use of ‘complex’ operations. Within the categories of ‘simple’ and ‘complex’, an increase in the variety of operations occurred. As a group, patients with ‘simple’ operations have been heavier, more often male and public pay patients than those who have undergone ‘complex’ operations. One year weight loss was greater for Roux-en-Y gastric bypass (RGB) than vertical banded gastroplasty (VBG), but follow-up rates were too low to study the relative merits of the operations used. The reported incidence of operative mortality and serious complications (leak with peritonitis, abscess and pulmonary embolism) remained low. Conclusions: These observations and their implications can be summarized in three statements which relate to action for improved patient care in the beginning of the new century: (1) increasing weight of candidates for surgical treatment during this decade indicates the need for earlier use of operative treatment before irreversible complications of obesity can develop; (2) low risk of obesity surgery, decreasing postoperative hospital stay, and early weight control support the continued and increased use of surgical treatment; (3) continued widespread use of both ‘simple’ and ‘complex’ operations with increased modifications of standard RGB and VBG procedures emphasizes the need for standardized long-term data and analyses regarding both weight control and postoperative side-effects.  相似文献   
9.
G Nichol  A Nix  P J Barnes    K F Chung 《Thorax》1990,45(9):694-698
The effect of inhaled prostaglandin (PG) F2 alpha on the response to the inhaled tussive agent capsaicin was investigated in normal subjects. Seven subjects inhaled three breaths of four doses of capsaicin (0.3, 0.6, 1.2, and 2.4 nmol) before and immediately after inhaling PGF2 alpha (0.1 mumol) or placebo (0.15M NaCl) on separate days. The numbers of capsaicin induced coughs were greater after PGF2 alpha (mean 42.3 coughs) than after 0.15M sodium chloride (30.1). Visual analogue scores (0-10 on a 10 cm continuous scale) showed that capsaicin was more irritant after PGF2 alpha than after saline. Total respiratory resistance (Rrs), measured by the forced oscillation technique, was unaltered throughout the study. A double blind, placebo controlled study of the effects of inhaled salbutamol (200 micrograms, 0.6 mumol) and ipratropium bromide (40 micrograms, 0.1 mumol) on cough induced by capsaicin (2.4 nmol) and by PGF2 alpha (0.1 mumol) and on PGF2 alpha augmented, capsaicin induced coughing was performed in seven subjects. Neither drug had any effect on capsaicin induced coughing. Salbutamol reduced coughing due to PGF2 alpha (mean 7.7 coughs after salbutamol, 9.3 after placebo) but ipratropium bromide did not (mean 6.9 coughs after ipratropium bromide, 6.6 after placebo). Salbutamol also inhibited the augmentation of the capsaicin induced cough that followed inhalation of PGF2 alpha (mean augmentation 1.9 coughs after salbutamol, 4.1 after placebo), whereas ipratropium bromide did not (augmentation 1.7 coughs after ipratropium bromide, 2.7 after placebo). No changes in Rrs were seen after PGF2 alpha or either drug. Thus salbutamol reduces PGF2 alpha induced cough and the augmentation of capsaicin induced cough that follows PGF2 alpha.  相似文献   
10.
The oncocytic Schneiderian papilloma (OSP) is a rare neoplasm of the nose and paranasal sinuses. The majority of the approximately twenty patients reported in the literature with this papilloma have been over the age of fifty at the time of diagnosis. The 33-year-old woman reported here is the youngest patient with this lesion to date. The OSP should be considered in the work-up of all unilateral nasal polypoid lesions. This lesion's propensity for recurrence and its documented association with synchronous malignant disease warrant surgical excision by en bloc resection of the lateral nasal wall, with corresponding careful microscopic evaluation of all excised tissue.  相似文献   
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