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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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Forty patients with chronic hepatitis C (CHC) were included in an open randomized controlled trial of lymphoblastoid α-interferon (L-IFN) versus no treatment. Twenty patients entered each group, and features of therapy and control cases were similar. L-IFN was given in low doses (1.5-4.5 megaunits) for 1 yr. In 16 of 20 patients treated with L-IFN (80%), but in only one of 20 nontreated cases (0.5%; p < 0.001), aminotransferase activities became normal. In four patients there was a reactivation of the disease during treatment after 4, 5, 6, and 8 months with normal aminotransferase levels. A posttherapy reactivation of hepatitis was observed in four additional cases after 1, 1, 1, and 3 months of follow-up. The other eight patients (40%) continued with normal aminotransferase levels for 1.52 ± 0.74 (range, 1-2.1) yr after IFN doses were discontinued. In all treated patients except two nonresponders, but in only one of 20 nontreated cases ( p < 0.001), Knodell's histological activity index decreased. Procollagen type III aminoterminal peptide levels did not change significantly in nontreated and nonresponder patients, diminished slightly in patients with a transient response, and normalized in cases with a long-standing response, suggesting that this serum test may be a reliable marker for monitoring response to IFIN therapy in patients with CHC. Finally, L-IFN treatment induced significant increments in CD4/CD8 index, phytohemagglutinin-induced blastogenesis, and natural killer activity. This study shows that L-IFN diminish inflammatory and fibrogenic activity in most patients with CHC. In 40% of patients treated in this trial, a long-standing remission of the disease was observed.  相似文献   
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The distribution of cholinergic nerve fibres, as well as the characterization of the muscarinic receptors responsible for the contraction, were determined in the detrusor smooth muscle of the sheep. The results obtained demonstrated a rich presence of acetylcholinesterase (AChE)-positive fibres distributed throughout the bladder body forming dense neuromuscular, subepithelial and perivascular plexuses. Furthermore, intramural ganglia containing AChE-positive cell bodies were identified. However, acetylcholine and carbachol induced a dose-dependent contraction of detrusor smooth muscle. The effect observed with carbachol was competitively antagonized by atropine (pA2: 8.94), pirenzepine (pA2: 7.38), AF-DX 116 (pA2: 7.35), 4-DAMP (pA2: 9.26) and hexahydroxiladifenidol (HHSiD) (pA2: 8.49). The pA2 value for pirenzepine is intermediate between M1- and M2-receptors which suggests that this antagonist does not act on M1- or M2-receptors, but that it does on M3-receptors. The pA2 value for AF-DX 116 is consistent with the presence of M2-receptors in this tissue. Moreover, the pA2 values obtained for both 4-DAMP and HHSiD are in agreement with the presence of M3-receptors, due to the lack of effect of pirenzepine on M1-muscarinic receptors. These results indicate the existence of a rich parasympathetic innervation in the sheep detrusor muscle and suggest that its contraction could be mediated by the stimulation of muscarinic receptors belonging to both M3- and M2-subtypes.  相似文献   
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The anatomic response to intravitreal bevacizumab injection in three patients with aggressive, posterior retinopathy of prematurity is described. In all cases, the worse eye was treated with a single intravitreal injection of 0.75 mg of bevacizumab as monotherapy or complementary to laser therapy. In 24 hours, all injected eyes showed regression of the tunica vasculosa lentis and iris vessel engorgement and disappearance of iris rigidity. In addition, plus disease and retinal proliferation began to regress. None of the eyes required additional treatment. Follow-up of up to 10 months  相似文献   
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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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