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891.
Dr. Y. F. Mangnall PhD D. D. Kerrigan FRCS A. G. Johnson MChir N. W. Read MRCP 《Digestive diseases and sciences》1991,36(12):1680-1684
Applied potential tomography (APT) is a new noninvasive, nonradioactive method of measuring gastric emptying, which generates profiles of emptying of liquids that are similar to those obtained simultaneously by scintigraphy and dye dilution. This study validates the ability of APT to measure emptying of a solid beefburger test meal from the stomach by comparing the results obtained with those obtained simultaneously by scintigraphy. When acid secretion was inhibited, there was a significant correlation between the two methods for the time taken for half the meal to empty from the stomach and the amount of meal emptied at different time intervals. Furthermore, the profiles of gastric emptying obtained by APT resembled those obtained by scintigraphy in most studies. If acid secretion was not inhibited, there was no correlation between values obtained by the two methods. 相似文献
892.
The effect of vascular endothelial growth factor on the healing of ischaemic skin wounds. 总被引:7,自引:0,他引:7
F Zhang M P Lei T M Oswald Y Pang B Blain Z W Cai W C Lineaweaver 《British journal of plastic surgery》2003,56(4):334-341
The effect of exogenous vascular endothelium growth factor (VEGF) on wound healing in an ischaemic skin flap model was evaluated in this study. Seventy-two Sprague-Dawley rats were used. Normal incisional wound and H-shaped double flaps were used as the wound models. The study was divided into two parts. In Part I, VEGF protein levels were determined from the incisional and H-shaped ischaemic wounds at 12 and 24 h, postoperatively. In Part II, tensile strength and immunohistochemical stains were examined to determine the level of microvessel density (MVD) at 1 and 2 weeks, postoperatively in simple incisional wounds, ischaemic wounds, and ischaemic wounds following 1 ml (1 microg/ml) exogenous VEGF injections into the subcutaneous tissue. The results showed a significantly higher level of VEGF protein in the ischaemic wounds than the incisional wounds. Tensile strength was statistically higher in the incisional wound group and in the ischaemic flap wounds with VEGF treatment compared to the ischaemic flaps with no treatment at 1 week, postoperatively (p>0.05). MVD data indicated that ischaemic wound repair with VEGF treatment had significantly higher MVD than the normal incisional wounds and ischaemic wounds without treatment. We conclude that exogenous application of VEGF can increase early angiogenesis and tensile strength in the ischaemic wound. 相似文献
893.
反坦克武器击中坦克时舱室内有害气体测试方法的探讨 总被引:1,自引:1,他引:0
为探讨在模拟实验条件下,坦克受到反我武器攻击后舱室内有害气体的取样方法和分析方法,用3种武器发射3种弹药攻击坦克,在远距离控制取样设备,取样后在实验室进行坦克舱室内有害气体浓度分析,结果取样成功,坦克被击中后,一氧化碳气体含量有明显的增高,氮氧化物、二氧化硫增高幅度不大,氧含量无明显变化,说明对坦克舱室进行远距离现场控制气体采样是可行的;坦克的受反坦克武器打击后,除弹片和冲击波等致伤因素外,还会造成坦克内乘员一氧化碳中毒。 相似文献
894.
目的研究骨髓基质细胞源内皮细胞移植对大鼠局灶性脑损伤超微结构的影响,探讨骨髓基质细胞源内皮细胞移植修复大鼠脑损伤的机制。方法制备大鼠局灶性脑损伤动物模型,进行骨髓基质细胞源内皮细胞移植,通过透射电镜观察损伤局部超微结构的变化。结果脑损伤后微血管内皮细胞胞浆广泛空泡变,细胞器明显减少,并出现核固缩,血管壁破坏。骨髓基质细胞源内皮细胞移植后微循环得到改善。结论脑损伤后出现微循环障碍是产生继发性脑缺血、脑水肿的病理基础。骨髓基质细胞源内皮细胞移植促进了损伤区微循环的改善。 相似文献
895.
目的:研究运动与心脏重塑过程中心肌胞浆游离Ca2 ([Ca2 ]c)动态变化的生物学机制.方法:采用激光扫描共聚焦显微技术(LSCM)对STDIn Ca2 荧光试剂负载的运动肥大心肌活细胞[Ca2 ]c动态变化进行研究,采用放射免疫测定运动小鼠心肌局部IGF-Ⅰ和AngⅡ含量.结果:运动肥大心肌[Ca2 ]c变化表现为基值稳态和峰值显著升高,达峰时间延长(P<0.001).心肌局部IGF-Ⅰ和AngⅡ显著升高(P<0.001).结论:运动性心肌肥大与[Ca2 ]c变化、机械信号、IGF-Ⅰ和AngⅡ关系密切,机械信号、IGF-Ⅰ和AngⅡ可能是引起[Ca2 ]c显著升高,增强心肌收缩能力的胞外刺激因素. 相似文献
896.
John McMahon RMN BA Scottish Home Health Department Nursing Research Fellow Staff Nurse Barry T Jones BSc PhD Senior Lecturer 《Journal of advanced nursing》1992,17(2):173-186
Despite being constantly cited as a critical intervening variable in the recovery from alcohol problems, there is a paucity of literature on client motivation. This paper reviews the current literature which impacts on motivation and its importance in treatment and develops in a stepwise manner the revised expectancy/motivation hypothesis, tentatively explaining both motivation and denial as a natural process in behavioural change. Because of the revised expectancy/motivation hypothesis' distinctly defined stages which closely relate to the process of nursing and the qualitative and quantitative measurement it entails which the nursing process demands, it offers a particularly appropriate model for treatment within nurse practice. 相似文献
897.
Kann Holmén RN Doctoral Student Kjerstin Ericsson RN PhD Researcher Lars Andersson DMSc Associate Professor Bengt Winblad MD Professor 《Journal of advanced nursing》1992,17(1):43-51
The purpose was to investigate experienced loneliness among the elderly. The material included 1725 people, aged 75 and over. The study describes relationships between loneliness, social network, cognitive function and health. Thirty-five per cent experienced loneliness, and a higher percentage was found among women. A gradual increase in loneliness was found up to the age of 90, after which a levelling was found. Elderly persons living together with a partner experienced less loneliness. There were no significant differences between those with and without children. Ten per cent reported not having any friends and, of these, one out of two experienced loneliness. A high frequency of experienced loneliness was found among elderly people with reduced cognitive function. Subjectively experienced bad health and loneliness were strongly related to each other, i.e. a person who experienced loneliness did usually not feel completely healthy. 相似文献
898.
899.
脐尿管占位性病变的CT诊断及鉴别诊断 总被引:5,自引:0,他引:5
目的 探讨CT检查在诊断和鉴别诊断脐尿管占位性病变方面的价值。方法根据临床病理证实的24例脐尿管占位性病变患者的CT影像学特征,分析其大小、部位、形态、性质、Retzius间隙影像学变化及增强后的影像学特征。结果 24例均明确诊断。4例为脐疝,其中3例疝囊内容物为网膜组织,另1例为肠管。20例为脐尿管占位性病变,均位于Retzius间隙内的脐尿管行走区,其中单纯性脐尿管囊肿6例,CT表现为长条椭圆形完整囊状包块,囊壁薄、光滑,囊内容物呈均匀低密度回声,增强后无强化;感染性脐尿管囊肿7例,CT表现为内部回声不均,灶周Retzius间隙内可见絮状或条索状密度增高影,其中4例囊壁明显增厚,3例囊壁不完整,2例呈多房性囊肿;脐尿管憩室伴结石3例,CT表现为中线处膀胱壁内可见高密度结石影;脐尿管肿瘤性病变4例,均于膀胱顶壁区中线处发现不规则软组织肿块影,增强后明显强化。结论 脐尿管占位性病变并不常见,多为感染性囊肿,结合临床术前确诊并不困难。CT是脐尿管占位性病变术前明确诊断和鉴别诊断的重要措施之一。 相似文献
900.
论中医病因、致病因素、邪气、邪之关系 总被引:2,自引:0,他引:2
张光霁 《浙江中医药大学学报》2007,31(6):676-677
邪是一切不正常、不正当的因素,邪气是邪的一部分,主要指六气异常以及疫疠之气等外感因素。两者可以独立于人体而存在,也可以进入人体,成为可能导致疾病的因素,即致病因素,邪(邪气)进入人体是致病因素,未进入人体不是致病因素。未导致疾痛的致病因素不是病因,已经引起疾病的致病因素是病因。 相似文献