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91.
目的通过训练大鼠急进高原模型从心肌组织形态和酶谱改变,研究训练对心肌损伤的防护。方法于海拔1520m实地环境设实验组(EG)采用中药抗疲I号加入常规饲料中喂养,对照组(CG)常规饲料喂养,EG、CG各40只游泳训练4周后,各选35只3h急进海拔3850m实地静息1.5h,从中各选10只作为静息对照采集标本,EG、CG各20只游泳至力竭后1h、24h采集标本;测定比较各组心肌酶谱指标等,镜下观察比较各组心肌形态变化。结果EG血中心肌酶谱指标1h、24h指标均优于CG1h、24h结果;心肌组织学结构从纵断面看,EG心肌结构清晰,肌丝细密,横纹清楚,核周无空隙;横断面心肌纤维群间隙小,毛细血管平均为10~12个/HPF;CG心肌纤维界限不清晰,肌丝分散,横纹不清楚,横断面心肌纤维群间隙增宽,毛细血管平均为3~5个/HPF,毛细血管腔扩张,红细胞堆积,提示有水肿。结论急进高海拔地区运动后可使心肌纤维缺氧水肿,血中心肌酶谱增高,同时会使心肌营养不良而发生结构改变,对心肌的供氧能力好坏必然决定运动能力强弱,过度训练、改变运动集训环境或强体力劳动均可引起心肌供血能力下降,本研究是通过抗疲I号加入食品干预训练大鼠的,有利于改善心肌营养与供氧状况,并能降低心肌纤维水肿发生。  相似文献   
92.
BACKGROUND: Despite constant improvements in caring for critically ill neonates and infants with congenital cardiac disease, sepsis, bone marrow and solid organ transplantation, acute renal failure (ARF) is an important problem in these children. ARF, severe fluid overload and inborn errors of metabolism are some of the indications for acute dialysis in infants and children. METHODS: The authors had retrospectively evaluated the medical records of Pediatric Intensive Care Unit, Ankara University School of Medicine, Ankara, Turkey patients who had required acute renal replacement therapy between the dates of January 2002 to February 2005. RESULTS: Medical records of 332 patients were reviewed. Acute renal replacement therapy was performed in 21 patients (6.3%; mean age, 9.6 +/- 7.4 years). Dialysis modalities were peritoneal dialysis in 15 patients (71.4%; mean age, 3.9 +/- 5.6 years) and hemodialysis in six patients (28.6%; mean age, 12.1 +/- 3.2 years). A total of 90% of patients had severe systemic disease leading to ARF. A total of 95% of patients had multiple organ dysfunction syndrome. The most common cause of ARF was refractory shock. At the beginning of renal replacement therapy, 10 patients were anuric, nine patients had volume overload, seven patients had decompensated metabolic acidosis and nine patients had hypotension. The average dialysis period was 4.7 +/- 6.4 days. Mortality rate was 66.7%. Eight patients recovered from ARF and chronic renal failure had developed in one patient. CONCLUSION: In the Pediatric Intensive Care Unit, ARF is frequently seen together with multiple organ dysfunction syndrome and the mortality rate is high. Both peritoneal dialysis and hemodialysis are important renal replacement treatment modalities in patients with ARF. The age and hemodynamic status of the patients are important when choosing treatment modality; generally peritoneal dialysis is preferred in infants and toddler, while hemodialysis is preferred in older children.  相似文献   
93.
花生过敏是造成人IgE诱导中毒反应的主要原因之一,本试验组制作C3H小鼠动物模型,并给其口服花生蛋白(PN)及霍乱毒素(CTx),然后在腹腔内注射PN(溶于明矾中的PN),使这种鼠即刻发生高度敏感症状(包括致死性的中毒反应)及花生特异性IgE水平增高,血浆息斯地明水平、脱颗粒肥大细胞及血管渗漏水平也大幅度升高。对照组小鼠未给药或仅仅接受了CTx,则未显示出花生特异性IgE水平升高及中毒症状。本文又分析了几种与中毒反应有关的参数。结果证明,小鼠花生过敏中毒反应与人花生过敏类似,同时小鼠花生过敏中毒反应模型,为研究中毒性免疫病理发生机制及研究更有效的治疗方案提供了一个有用的工具。  相似文献   
94.
Three children with azotaemic renal osteodystrophy were treated with 1,25-dihydroxycholecalciferol (1,25(OH)2D3). All showed clinical, biochemical, and radiological improvement within 6 months of starting treatment. There were no complications. The dose of 1,25(OH)2D3 required was 0-5 microgram per day for 2 children aged 22 and 30 months, and 2 microgram per day for a 15-year-old boy. 2 of the patients were receiving phenobarbitone and phenytoin and in one of them prior treatment with dihydrotachysterol 0-5 mg daily and 6 microgram 1alpha-hydroxycholecalciferol (1alphaOHD3) daily had failed to induce improvement. In one patient, in whom serial iliac bone samples were available, 2 microgram 1,25(OH)2D3 resulted in histological improvement in previously severe osteomalacia. 1,25(OH)2D3 appears to be an effective and safe drug in the treatment of uraemic osteodystrophy.  相似文献   
95.
本文报告了用电化学检测器的高效液相色谱法测定血清及尿中速尿含量的方法。样品予处理方法:血清用乙腈除蛋白,尿用蒸馏水稀释50倍。采用作者合成的FD-Val-OH作为内标物。色谱条件为:反相柱,以含35%乙醇的5mmol/L四丁基铵水溶液为流动相(pH7.50),流速1.0ml/min;用电化学检测器,检测电压0.90V:速尿及内标物的保留时间分别为10和15min。通过计算速尿对内标物的峰高比求得速尿含量。血清及尿中的最低检测浓度分别为16和9ng/ml。标准曲线在0.25~5ng/μl(血清)、0.5~10ng/μl(尿)的浓度范围内呈线性关系。血清及尿中回收率分别为100.5%和100.6%。变异系数在4.6%以下。  相似文献   
96.
目的:探讨高血压丘脑出血破入脑室的治疗方法。方法:回顾分析本院高血压丘脑出血破入脑室30例患者的临床资料,15例行双侧脑室外引流术,6例行血肿穿刺引流+脑室外引流,5例行开颅血肿清除,4例意识清醒。结果:生活自理18例,中残6例,重残3例,死亡3例。结论:高血压丘脑出血破入脑室者应急诊行脑室外引流。  相似文献   
97.
Background  Palmoplantar pustulosis (PPP) discloses some differences compared to vulgar psoriasis (PV) in terms of age of onset, female predominance and low occurrence of psoriasis lesions elsewhere. Cigarette smoking has been associated to PPP in international studies; nevertheless, these studies were never performed among Brazilian.
Objectives  To compare prevalence of smoking among PPP, PV and other dermatologic patients (NPD).
Methods  Case–control study involving 25 PPP patients from a reference psoriasis centre. Two control groups were matched according to gender and age: 50 patients with PV and 50 NPD. Confounders were adjusted by conditional multiple logistic regression.
Results  Among cases, 84.0% were female and PPP age of disease onset (41.4 years) was greater than PV (34.5 years). Prevalence of ever smoking was higher among cases (92.0%) than PV (52.0%) and NPD (30.0%). Adjusted odds ratio of PPP ever smoking compared to PV and NPD was 9.5 and 36.2, respectively. All smokers reported the onset of their habit before the development of PPP.
Conclusions  There was significant association between PPP and smoking. However, the impact of giving it up in the clinical course of the disease remains to be established.  相似文献   
98.
富氧对缺氧大鼠心肌琥珀酸脱氢酶及超微结构的影响   总被引:2,自引:0,他引:2  
目的:探讨富氧对缺氧大鼠心肌损伤的保护作用及机理。方法:雄性Wistar大鼠32只随机分为平原对照组、低氧组、富氧组,低氧组在模拟海拔5400m低压舱内24h,富氧组在模拟5400m的低压舱内12h,然后富氧(27.0%的氧混合气)12h,观察心肌琥珀酸脱氢酶(SDH)及超微结构的改变。结果:低氧组心肌细胞灶性变性坏死,肌丝溶解凝固,间质水肿液和纤维素样渗出。富氧组心肌无明显病变,仅滑面内质网轻度扩张。富氧组SDH活性明显高于低氧组。结论:低氧导致心肌SDH活性及超微结构的改变,富氧对心肌有保护作用。  相似文献   
99.
Swett  HA; Fisher  PR; Cohn  AI; Miller  PL; Mutalik  PG 《Radiology》1989,172(2):487-493
Conventional computer-based medical expert systems deliver advice to physicians as written text. While such advice is useful, it has distinct limitations in a visually oriented discipline such as diagnostic radiology, in which decisions often depend on pattern recognition and appreciation of subtle morphologic features. The authors developed a prototype expert computer system, IMAGE/ICON, which displays groups of images sorted into a series of axes based on different ways in which they may be similar. They may share a common feature, group of features, causes, or clinical setting. IMAGE/ICON may display examples of morphologic variations of a dominant finding or a spectrum of abnormalities seen in an specific disease or group of diseases. The system also assembles a written analysis of key features of a case. Such a tool may be useful as a diagnostic aid or for continuing medical education. It is likely to have particular impact in the form of an intelligent radiologic workstation, as picture archiving and communication systems become available.  相似文献   
100.
目的 总结6例新型冠状病毒肺炎(COVID-19)患者的临床特征和影像学表现,为COVID-19早期确诊和临床干预提供依据。方法 选择上海中医药大学附属第七人民医院2020年1月1日至2020年2月22日严重急性呼吸综合征冠状病毒2(SARS-CoV-2)核酸检测阳性的6例COVID-19患者,回顾性分析流行病学史、临床表现、影像学资料和实验室检查。结果 6例患者均有明确的武汉旅行或居住史,4例患者有发热,3例有咳嗽,2例有流涕、咽痛等上呼吸道症状,2例有头痛、肌肉酸痛等全身症状。6例患者胸部CT检查均可见肺部异常表现,病灶均为双侧分布,下肺病灶多于上肺,主要表现为双侧肺野外带多发磨玻璃影、实变影、“铺路石”征及不同程度纤维化。发病后较晚行胸部CT检查可见肺实变和明显纤维化。结论 COVID-19影像学具有一定的特征性表现,结合患者流行病学史、临床表现和SARS-CoV-2核酸检测能早期诊断。  相似文献   
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