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991.
Southgate  M. Therese 《JAMA》2006,296(13):1564
  相似文献   
992.
目的 探讨Lugol液染色对食管早期癌和癌前病变的诊断价值。方法 对45例食管黏膜可疑病变经内镜以2%Lugol液喷洒染色,观察黏膜染色情况,并取活检送病理组织学检查。结果 45例食管病变染色后,39例呈浅染色或不染色,其中食管癌8例(食管早期癌5例,进展期癌3例),Barrett食管5例,轻至中度不典型增生1l例。本组Lugol液染色对食管早期癌和癌前病变的检出率达46.7%。结论 内镜下应用Lugol液染色结合活检有助于食管早期癌和癌前病变的诊断,且操作简便,具有重要的临床价值。  相似文献   
993.
994.
彩色多普勒超声在Graves''''病诊断中的作用   总被引:1,自引:0,他引:1  
目的:探讨彩色多普勒超声在Graves’病(又称弥漫性甲状腺肿)诊断中的作用。方法:用能量多普勒超声观察40例Graves’病患者及40例正常对照组双侧甲状腺组织的血液供应及分布情况;用脉冲多普勒测量颈总动脉的收缩期峰值流速(VPS),甲状腺上动脉的收缩期峰值流速(VPS)及阻力指数(RI),测量甲状腺上动脉的内径。结果:Graves’病组甲状腺实质内的血供极为丰富,血流分级以Ⅲ级为主,呈“火海征”,Graves’病组与正常对照组相比有显著性差异,P<0.005。Graves’病组颈总动脉的收缩期峰值流速为(162.1±31.5)cm/s,正常对照组颈总动脉的收缩期峰值流速为(98.2±20.9)cm/s,Graves’病组甲状腺上动脉的收缩期峰值流速(108.7±35.6)cm/s,正常对照组甲状腺上动脉的收缩期峰值流速(42.1±15.1)cm/s,以上各参数Graves’病组甲状腺上动脉的阻力指数为0.55±0.11,正常对照组甲状腺上动脉的阻力指数为0.73±0.19。Graves’病组与正常对照组相比有显著性差异P<0.01。Graves’病组甲状腺上动脉的内径为3.34±1.16mm,正常对照组甲状腺上动脉的内径为1.62±1.24mm。Graves’病组与正常对照组相比有显著性差异P<0.01。结论:彩色多普勒超声在Graves’病诊断中有重要的作用。  相似文献   
995.
丹参对持续癫痫幼鼠脑损伤保护作用的实验研究   总被引:2,自引:0,他引:2  
李伟  马华 《武警医学》2006,17(3):182-185,F0004
目的 探讨丹参对持续癫痫发作诱发幼鼠脑神经元损伤是否具有保护作用。方法 皮下及腹腔注射贝美格针诱发健康幼龄鼠癫痫持续状态发作。光镜下观察神经元病变情况;电镜观察海马神经元超微结构的改变。结果 持续癫痴组幼鼠脑组织光镜下可见明显的神经元病变。电镜下可见海马区神经元的超微结构病变。丹参治疗组神经元病变均轻于持续癫痴组;而正常对照组未见类似病变。结论 丹参在组织、细胞和亚细胞水平对持续癫病幼鼠脑神经元损伤具有一定的保护作用,为临床有效防治小儿惊厥性脑损伤提供了可靠的实验依据。  相似文献   
996.
166Ho-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetramethylene-phosphonate (DOTMP) is a tetraphosphonate molecule radiolabeled with 166Ho that localizes to bone surfaces. This study evaluated pharmacokinetics and radiation-absorbed dose to all organs from this beta-emitting radiopharmaceutical. METHODS: After two 1.1-GBq administrations of 166Ho-DOTMP, data from whole-body counting using a gamma-camera or uptake probe were assessed for reproducibility of whole-body retention in 12 patients with multiple myeloma. The radiation-absorbed dose to normal organs was estimated using MIRD methodology, applying residence times and S values for 166Ho. Marrow dose was estimated from measured activity retained after 18 h. The activity to deliver a therapeutic dose of 25 Gy to the marrow was determined. Methods based on region-of-interest (ROI) and whole-body clearance were evaluated to estimate kidney activity, because the radiotracer is rapidly excreted in the urine. The dose to the surface of the bladder wall was estimated using a dynamic bladder model. RESULTS: In clinical practice, gamma-camera methods were more reliable than uptake probe-based methods for whole-body counting. The intrapatient variability of dose calculations was less than 10% between the 2 tracer studies. Skeletal uptake of 166Ho-DOTMP varied from 19% to 39% (mean, 28%). The activity of 166Ho prescribed for therapy ranged from 38 to 67 GBq (1,030-1,810 mCi). After high-dose therapy, the estimates of absorbed dose to the kidney varied from 1.6 to 4 Gy using the whole-body clearance-based method and from 8.3 to 17.3 Gy using the ROI-based method. Bladder dose ranged from 10 to 20 Gy, bone surface dose ranged from 39 to 57 Gy, and doses to other organs were less than 2 Gy for all patients. Repetitive administration had no impact on tracer biodistribution, pharmacokinetics, or organ dose. CONCLUSION: Pharmacokinetics analysis validated gamma-camera whole-body counting of 166Ho as an appropriate approach to assess clearance and to estimate radiation-absorbed dose to normal organs except the kidneys. Quantitative gamma-camera imaging is difficult and requires scatter subtraction because of the multiple energy emissions of 166Ho. Kidney dose estimates were approximately 5-fold higher when the ROI-based method was used rather than the clearance-based model, and neither appeared reliable. In future clinical trials with 166Ho-DOTMP, we recommend that dose estimation based on the methods described here be used for all organs except the kidneys. Assumptions for the kidney dose require further evaluation.  相似文献   
997.
998.
Volume and profile of alcohol consumption among students and classmates as predictors of aggression and victimization: a multilevel analysis among Swiss adolescents

Objective:  

To test the effects of the volume of alcohol consumption and drinking patterns on alcohol-related aggression and victimization, both at the individual and class levels.  相似文献   
999.
Vacuum-assisted closure (VAC), although a modern adjunct in wound management, has not been used previously in pyoderma gangrenosum (PG), probably to avoid the potential complications of ‘pathergy’. We would like to report our experience of VAC in three cases of PG with the relevant review of literature.  相似文献   
1000.
PURPOSE: The variable-pitch pulse oximeter is an important intraoperative patient monitor. Our ability to hear its auditory signal depends on its acoustical properties and our hearing. This study quantitatively describes the audio spectrum and sound pressure levels of the monitoring tones produced by five variable-pitch pulse oximeters. METHODS: We compared the Datex-Ohmeda Capnomac Ultima, Hewlett-Packard M1166A, Datex-Engstrom AS/3, Ohmeda Biox 3700, and Datex-Ohmeda 3800 oximeters. Three machines of each of the five models were assessed for sound pressure levels (using a precision sound level meter) and audio spectrum (using a hanning windowed fast Fourier trans-form of three beats at saturations of 99%, 90%, and 85%). RESULTS: The widest range of sound pressure levels was produced by the Hewlett-Packard M1166A (46.5 +/- 1.74 dB to 76.9 +/- 2.77 dB). The loudest model was the Datex-Engstrom AS/3 (89.2 +/- 5.36 dB). Three oximeters, when set to the lower ranges of their volume settings, were indistinguishable from background operating room noise. Each model produced sounds with different audio spectra. Although each model produced a fundamental tone with multiple harmonic overtones, the number of harmonics varied with each model; from three harmonic tones on the Hewlett-Packard M1166A, to 12 on the Ohmeda Biox 3700. There were variations between models, and individual machines of the same model with respect to the fundamental tone associated with a given saturation. CONCLUSION: There is considerable variance in the sound pressure and audio spectrum of commercially-available pulse oximeters. Further studies are warranted in order to establish standards.  相似文献   
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