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LN Weinberger MJ Zirwas JC English III 《Journal of the European Academy of Dermatology and Venereology》2007,21(2):156-162
Male genital oedema can be defined as swelling or the appearance of swelling of the scrotum and/or the penile shaft and prepuce. Despite the various causes of genital oedema reported in the published work, a concise approach to the evaluation and management has not been sufficiently addressed. 相似文献
3.
Matthew D Robson Peter D Gatehouse Graeme M Bydder Stefan Neubauer 《Magnetic resonance in medicine》2004,51(5):888-892
Phosphorus was imaged in vivo in human cortical and trabecular bone and the T(1) and T(2) (*) were measured. An ultrashort TE (UTE) pulse sequence (TE = 70 microm) was used with half pulse excitation and radial mapping of k-space from the center out. T(2) (*) was measured using multiple echo times and T(1) was measured both by saturation recovery and by a method using different RF pulse amplitudes. Seven normal subjects (32-85 years) were examined. Phosphorus was imaged, with a true in-plane resolution of 2.9 x 2.9 mm and a signal-to-noise ratio (SNR) of 19:1, in both cortical and trabecular bone. The mean T(2) (*) value was 207 +/- 12 micros, and the mean T(1) value was 8.6 +/- 3.0 sec. Images and measurements were obtained in realistic times on a clinical MR system. This may provide a new approach to characterizing disease of bone. 相似文献
4.
Critical features of bacterial mutation assays 总被引:1,自引:1,他引:1
D Gatehouse 《Mutagenesis》1987,2(5):397-409
This review discusses features of the standard protocols currently used in bacterial mutation assays which can have a critical effect upon the test outcome. Such features if not strictly controlled may affect the results qualitatively as well as quantitatively. These include the dose-intervals of the test compound used; the number of bacterial cells exposed to the test compound; the phase of growth such cells are in during exposure; and the length of time that the cells are exposed prior to the addition of soft agar (in the Salmonella/plate incorporation assay). The following possible modulating effects will also be discussed: the nature of the solvent used; the nature and quantity of the exogenous metabolizing system (usually liver S9-fraction) and the quantity of amino-acid (e.g. histidine) within the test system being that either deliberately added or present unavoidably within the test sample (e.g. biological fluids). If bacterial mutagenicity assays are to realize their full potential for the detection of genotoxic carcinogens, the use of rigid protocols should be discouraged. Where possible, consideration of the compound's structure should lead to the employment of the optimal protocol for the detection of genotoxic carcinogens within that chemical class. The relative speed and low cost of bacterial assays should be exploited in this way to avoid the generation of false negative results during the primary screening of novel compounds. 相似文献
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Cleverley JR Desai SR Wells AU Koyama H Eastick S Schmidt MA Charrier CL Gatehouse PD Goldstraw P Pepper JR Geddes DM Hansell DM 《Clinical radiology》2000,55(1):45-50
AIM: A number of imaging techniques have been used for the pre-operative assessment of patients for lung volume reduction surgery (LVRS). We evaluated whether data currently acquired from perfusion scintigrams and cine MR of the diaphragm are obtainable from high resolution CT (HRCT) of the thorax. MATERIALS AND METHODS: Thirty patients taking part in a randomized controlled trial of LVRS against maximal medical therapy were evaluated. HRCT examinations (n= 30) were scored for (i) the extent and distribution of emphysema; (ii) the extent of normal pulmonary vasculature; and (iii) diaphragmatic contour, apparent defects and herniation. On scintigraphy, (n= 28), perfusion of the lower thirds of both lungs, as a proportion of total lung perfusion (LZ/T(PERF)), was expressed as a percentage of predicted values (derived from 10 normal control subjects). On cine MR (n= 25) hemidiaphragmatic excursion and coordination were recorded. RESULTS: Extensive emphysema was present on HRCT (60% +/- 13.2%). There was strong correlation between the extent of normal pulmonary vasculature on HRCT and on perfusion scanning (r(s)= 0.85, P< 0.00005). Hemidiaphragmatic incoordination on MR was weakly associated with hemidiaphragmatic eventration on HRCT (P= 0.04). CONCLUSION: The strong correlation between lung perfusion assessed by HRCT and lung perfusion on scintigraphy suggests that perfusion scintigraphy is superfluous in the pre-operative evaluation of patients with emphysema for LVRS. 相似文献
7.
Yang PY Almofti MR Lu L Kang H Zhang J Li TJ Rui YC Sun LN Chen WS 《第二军医大学学报》2006,27(6):637-637
Polygonum multiflorum stilbeneglycoside (PMS) is a water-soluble fraction of Polygonum multiflorum Thunb. , one of the most famous tonic traditional Chinese medicines, that has protective effects on the cardiovascular system. The purpose of the present study is to elucidate the effects of PMS on macrophage-derived foam cell functions and the reduction of severity of atherosclerosis in hypercholesterolemic New Zealand White (NZW) rabbits. NZW rabbits were fed for 12 weeks with a normal diet, a high cholesterol diet, or a high cholesterol diet associated with irrigation with different doses of PMS (25, 50, or 100 mg/kg). Treatment of NZW rabbits fed with high cholesterol diet with 100 mg/kg PMS attenuated the increase in plasma cholesterol, low-density lipoprotein cholesterol, very low-density lipoprotein cholesterol, and plasma triglyceride. Treatment with 50 and 100 mg/kg PMS caused 43% and 60% decrease in atherosclerotic lesioned area ratio to total surface area, respectively. In U937 foam cells, PMS could decrease the high expression of intercellular adhesion molecule (ICAM)-1 protein and the vascular endothelial growth factor (VEGF) protein levels in the medium induced by oxidized lipoprotein when analyzed by flow cytometry. The results proved that PMS is a powerful agent against atherosclerosis and that PMS action could possibly be through the inhibition of the expression of ICAM-1 and VEGF in foam cells. 相似文献
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目的研究β-catenin异常表达、c-myc和Cyclin D1的高表达与胰腺癌发生、浸润、转移的关系。方法应用免疫组织化学方法检测5例正常胰腺组织和40例胰腺癌及13例相应癌旁组织中β-catenm、c-myc和Cyclin D1的表达。结果 5例正常胰腺组织及13例胰腺癌旁组织中β-catenin为正常表达,c-myc和Cyclin D1阴性表达,40例胰腺癌组织中25例有β-catenin的异常表达(25/40,62.5%),20例(20/40,50%)有c-myc的高表达,23例(23/40,57.5%)有Cyclin D1的高表达。β-catenin的异常表达率与淋巴结转移、浸润及病理分级相关(P<0.05),c-myc和Cyclin D1的高表达与分化程度,浸润,转移及病理分级无关,β-catenin的异常表达与c-myc的阳性表达不相关,而与Cyclin D1的阳性表达相关。结论β-catenin的异常表达可能主要是通过激活Cyclin D1引起细胞增殖,导致肿瘤的发生。 相似文献
10.
KH Neppelenbroek RS Seó VM Urban S Silva LN Dovigo JH Jorge NH Campanha 《Oral diseases》2014,20(4):329-344
In healthy individuals, Candida species are considered commensal yeasts of the oral cavity. However, these microorganisms can also act as opportunist pathogens, particularly the so‐called non‐albicans Candida species that are increasingly recognized as important agents of human infection. Several surveys have documented increased rates of C. glabrata, C. tropicalis, C. guilliermondii, C. dubliniensis, C. parapsilosis, and C. krusei in local and systemic fungal infections. Some of these species are resistant to antifungal agents. Consequently, rapid and correct identification of species can play an important role in the management of candidiasis. Conventional methods for identification of Candida species are based on morphological and physiological attributes. However, accurate identification of all isolates from clinical samples is often complex and time‐consuming. Hence, several manual and automated rapid commercial systems for identifying these organisms have been developed, some of which may have significant sensitivity issues. To overcome these limitations, newer molecular typing techniques have been developed that allow accurate and rapid identification of Candida species. This study reviewed the current state of identification methods for yeasts, particularly Candida species. 相似文献