电磁脉冲诱导大鼠心肌闰盘间隙开放及其机制

目的 探讨电磁脉冲(EMP)诱导心肌闰盘(ID)的改变及其作用机制。方法 用EMP模拟发生器,场强为50~400 kV/m,脉冲次数200次,雌性SD大鼠30只,随机分为5组,每组6只。照后12 h时采用硝酸镧示踪法和透射电子显微镜观察心肌ID结构的改变,用基因芯片检测受照心肌差异基因表达谱。结果 照后12 h,辐照组的ID间隙随着EMP场强的增加而逐渐增宽,ID间隙中沉积的镧颗粒随着EMP场强的增加而逐渐增多。200 kV/m 组与对照组相比差异表达基因有108个,其中表达上调基因有synaptorin、VGF、HSP70等51条,下调基因有NAD、FGF、Tff3等57条。结论 在场强为50~400 kV/m EMP范围内辐照可诱导心肌ID间隙开放,且随场强的增加而增宽,以400 kV/m时最为显著,受照心肌有108个基因差异表达。     

电磁脉冲辐射后小鼠免疫器官损伤的病理研究

目的 :研究电磁脉冲 (EMP)照射后小鼠脾脏和胸腺的组织病理变化。方法 :198只小鼠经 6× 10 4V/m电磁脉冲辐照后 6h、1d、3d、7d、14d、2 8d、3个月、6个月、9个月和 12个月共 10个时相点活杀取脾脏和胸腺 ,分别应用光镜和电镜进行组织学和超微结构观察。结果 :电磁脉冲辐照后早期 :脾脏脾小体结构不清 ,体积缩小 ,生发中心不明显 ;淋巴细胞核固缩、崩解 ;红髓中巨噬细胞增多 ,血窦扩张、充血明显。照后中期 :脾脏红髓纤维化 ;胸腺皮质细胞变性坏死 ,髓质内可见灶状出血 ,出血灶周围细胞核固缩。照后后期 :脾脏出现“假小叶”状纤维化 ,胸腺皮质变薄 ,髓质变宽 ,皮髓质比例倒置 ,髓质内纤维组织增生甚至纤维化。照后晚期 :脾脏被膜增厚 ,胸腺出现萎缩 ,脾脏和胸腺中的淋巴细胞均有所恢复。在透射电镜下 ,脾脏和胸腺内淋巴细胞均出现典型的凋亡图像。结论 :电磁脉冲辐照后脾脏和胸腺发生明显损伤 ,脾脏损伤更为严重和迅速 ,其病变具有进行性、阶段性及缓慢恢复性特点 ,表明免疫系统器官为EMP辐照敏感组织之一。     

电磁脉冲暴露对雄性BALB/c小鼠子代性别比的影响

目的 探讨雄性BALB/c小鼠电磁脉冲（electromagnetic pulse,EMP）暴露对子代性别比的影响。方法 BALB/c小鼠雄性33只,雌性66只。雄性小鼠按照体重随机分为10 000次、100 000次脉冲辐照组和假辐照组。雌性小鼠相同环境分隔饲养,用以合笼。辐照组给予场强35 kV/m,重复频率50 Hz,脉冲数分别为10 000次和100 000次的辐照,每日1次,连续辐照2周。辐照后按雌雄比2：1合笼1周,1周后处死雄鼠,对比分析3组雄鼠的体重和睾丸重量,计算体睾指数;游离附睾中精子进行计数。孕鼠于孕20 d解剖取胎鼠组织进行PCR,鉴定子代性别比。结果与假辐照组相比,10 000次辐照组和100 000次辐照组雄鼠的体重、睾丸重量和体睾指数差异不大;精子计数均有下降,但差异无统计学意义。10 000次辐照组子代性别比（雄性：雌性）为0.298明显低于假辐照组0.871（χ²=9.37,P<0.01）;100 000次辐照组为0.826,与假辐照组相比差异无统计学意义。结论 雄性小鼠在场强35 kV/m,重复频率50 Hz,脉冲次数10 000次的EMP中暴露,可能导致子代雄性与雌性性别比降低。     

电磁脉冲辐照对培养大鼠小脑神经细胞内LDH和培养上清中LDH,CHE,K+和Na+浓度的影响

目的以体外原代培养的小脑颗粒细胞为对象,测定电磁脉冲辐照神经细胞前后细胞内LDH和培养上清中LDH,CHE,K+和Na+浓度及与时间的关系,研究电磁脉冲(场强为6×104 V/m)辐照后早期对小脑颗粒细胞损伤的可能机制.方法在培养12～14d时,高场强EMP模拟源(有界波模拟源),场强为6×104 V/m,脉冲上升时间为20ns,脉宽为30μs,频率包含0～100MHz,以2.5次/min,辐照2min.并于辐照后0(即刻),1,6,12和24h应用生化检测试剂盒测定细胞内和培养上清中LDH及培养上清中CHE,K+和Na+浓度.结果电磁脉冲辐照后即刻就可引起培养上清LDH明显升高;辐照后1h细胞内LDH明显降低,而培养上清中LDH,CHE和K+明显升高;辐照后6h细胞内LDH明显降低,而培养上清中LDH,CHE,K+ 和Na+明显升高;辐照后12h细胞内LDH明显降低,培养上清中CHE,K+ 和Na+明显升高;辐照后24h所有上述指标基本恢复.结论电磁脉冲辐照后可损伤大鼠海马神经元细胞膜.     

电磁脉冲暴露对雄性成年小鼠生殖的影响

目的 探讨电磁脉冲（EMP）对雄性小鼠生殖的影响。方法 48只健康成年雄性BALB/c小鼠（8周龄）,用随机数表法分为假暴露组和暴露组,每组24只。动物进行EMP全身暴露或假暴露,EMP场强720 kV/m,脉宽40 ns,重复频率1 Hz,脉冲次数100次。EMP暴露后不同时间（1、7、14和35 d）腹腔麻醉小鼠,剥离双侧附睾尾,游离精子,检测精子质量（包括精子数量、畸形率和存活率）;剥离双侧睾丸,HE染色法观察其组织形态,测量生精小管直径;ELISA和Western blot检测睾丸组织内干细胞因子（SCF）和胶质源性神经营养因子（GDNF）的水平。结果 EMP暴露后1、7、14和35 d,与假暴露组相比,暴露组小鼠的精子质量和睾丸形态结构无明显改变（P>0.05）;小鼠生精小管直径,暴露组分别为（196.85±16.65）、（196.79±14.33）、（196.35±22.71）和（198.60±25.88）μm;假暴露组分别为（204.31±27.13）、（197.07±18.11）、（194.37±21.45）和（200.59±19.36）μm,两组比较差异无统计学意义（P>0.05）。SCF和GDNF水平在EMP暴露后不同时间差异无统计学意义（P>0.05）。结论 本实验条件下的EMP暴露对成年雄性小鼠的睾丸结构和生殖功能无明显影响。     

电磁脉冲辐照对培养大鼠垂体细胞上清中LDH、AST、CHE、K+ 和Na+ 的影响

对Wistar大鼠垂体细胞在6孔板中进行原代培养,在培养第4天时,用高场强EMP模拟源(场强为6×104 V/m,脉冲上升时间为20ns,脉宽为30μs),2min内辐照5次.并于辐照后0(即刻)、1、6、12和24h应用中生公司生化检测试剂盒测定培养上清中LDH、AST、CHE、K+、Na+浓度,探讨电磁脉冲对垂体细胞损伤的机制.结果表明,电磁脉冲辐照后即刻就可引起培养上清LDH和CHE明显升高;辐照后1和6h培养上清中LDH、AST、CHE、和K+明显升高;辐照后12h培养上清中LDH、AST和K+明显升高;辐照后24h所有上述指标基本恢复.结果提示,电磁脉冲辐照后可引起大鼠垂体细胞膜的损伤.     

电磁脉冲对记忆的影响及其机制的研究

目的研究电磁脉冲(EMP)辐照对动物记忆力影响并探讨其作用机制.方法①行为实验用穿梭箱训练成年大鼠,使之形成条件反射,采用高场强EMP(6×104 V/m)进行照射,并于照后即刻,3 h,6 h,12 h,24 h分别进行测试,观察其对记忆保持能力的影响;②照射后大鼠活杀取脑,HE和神经元尼氏体染色,组织形态学观察;③海马神经元原代培养,经EMP辐照后观察形态改变,并采用流式细胞仪检测其凋亡情况.结果照射后即刻大鼠的主动回避反应减少,而被动逃避反应增多,与照射前相比有非常显著性差异(P<0.01),3 h后渐趋照前水平;照射前后大鼠对刺激做出反应的潜伏期无统计学差异(P>0.05).EMP照射可造成海马组织和培养神经元的变性、凋亡、坏死及血液循环障碍等病理改变.结论EMP照射可迅速造成实验大鼠暂时的记忆力下降,使海马组织细胞损伤及其凋亡增加,上述改变可能是EMP致脑功能障碍的病理学基础之一.     

葛根水提取物对小鼠红细胞膜脂流动性和血常规的影响

目的研究葛根水提取物对小鼠红细胞膜脂流动性和血常规的影响。方法小鼠给予葛根水提取物(0.01、0.1、1g·ml-1)3个剂量,并设阴性、阳性对照组,连续给药20d,于停药次日眼球取血,用DPH荧光探针法测定红细胞膜脂流动性;用血细胞分析仪进行血常规检测。结果葛根水提取物0.1、1g·ml-1剂量组、阳性对照组与阴性对照组相比,红细胞膜脂流动性有显著增高(P<0.05),并显著降低微黏度(P<0.05)。血常规检测中葛根水提取物3个剂量组,阳性对照组与阴性对照组相比WBC、MCV、PLT有轻微下降的趋势,无显著影响(P>0.05)。结论葛根能明显升高红细胞膜脂流动性,降低微黏度,改善微循环,具有良好的活血化瘀作用。使用中注意其不良反应,定期检查血常规。     

北豆根水提物对小鼠红细胞膜流动性和血常规的影响

目的 研究北豆根水提物对小鼠红细胞膜流动性和血常规的影响.方法 对3组小鼠分别给予浓度为1、0.5、0.25g·ml-1的北豆根水提物,连续给药3周,并设生理氯化钠溶液组作为对照.利用血细胞分析仪进行血液成分测定,采用DPH荧光探针法测定红细胞膜流动性.结果 血常规检测中北豆根水提物3个剂量组,与生理氯化钠溶液组比较白细胞数量(WBC)有下降趋势,中浓度组有显著性差异;平均血细胞容积(MCV)、血红蛋白含量(HGB)显著降低;低、中浓度组红细胞(RBC)有上升趋势,低浓度组有统计学差异;血小板(PLT)显著升高(P＜0.01).北豆根低、中浓度组可显著增加红细胞膜流动性,降低微黏度,而高浓度组的作用不明显.结论 一定浓度的北豆根水提物可以增加红细膜流动性,从而降低血液黏度,改善血液流变指标.     

原核pprI基因活体转染对BALB/c小鼠急性放射损伤保护作用的研究

目的 研究耐辐射奇球菌pprI基因活体转染对小鼠急性放射损伤的防护作用.方法 采用SPF级纯品系BALB/c雄性小鼠,应用活体电转染技术,将pEGFP-c1空载质粒及pEGFP-c1-pprI基因重组质粒转入小鼠股前肌肉.应用60Coγ射线进行全身照射,死亡率观察组吸收剂量为6 Gy,观察照后30 d内小鼠死亡率的变化;放射效应观察组吸收剂量为4 Gy,于照后1、7、14、28和35 d观察小鼠外周血象、胸腺、脾脏和骨髓细胞的凋亡率,并于照后第7和28天观察小鼠肺脏和睾丸组织的病理变化.结果 质粒注射剂量为50 μg/50μl,电场强度为200 V/cm时转染肌细胞的效率最高.pEGFP-c1-pprI基因重组质粒转染组小鼠急性辐射死亡率为30％,显著低于单纯照射组(60.0％)和空载体组(63.3％)(x2=4.90、6.24,P＜0.05).与单纯照射组、空载体组比较,pEGFP-c1-pprI基因重组质粒转染组小鼠的外周血白细胞计数在照后1、7、14和28 d显著增高(F=16.26、8.10、6.37、10.74,P＜0.05),血小板计数在照后第7和14天显著增高(F=7.36、5.71,P＜0.05),淋巴细胞百分率在照后7d显著增高(F=18.43,P＜0.05);胸腺和骨髓细胞凋亡率均在照后第1、7、14、28和35天显著降低(F=3.88、14.91、14.14、39.86、5.65,P＜0.05;F=53.70、11.75、21.78、41.40、4.54,P＜0.05);脾脏细胞凋亡率在照后第1、7、14和28天显著降低(F=97.95、56.61、33.55、14.71,P＜0.05).pEGFP-c1-pprI基因重组质粒转染组小鼠肺脏和睾丸的放射病理损伤较轻并且恢复较快.结论 耐辐射奇球菌pprI基因活体电转染对BALB/c小鼠急性放射损伤具有显著的保护作用,为进一步临床应用奠定了实验基础.     

成批煤气爆燃烧伤的救治体会

报道治疗因煤气泄漏爆炸烧伤病员7例，经应用MEBT技术积极救治，其中6例于伤后17天痊愈出院，另一例特重伤员也于伤后30天康复出院。作者认为：应严格按照MEBT／MEBO要求进行规范治疗，正确处理生命体征、休克、感染、脏器功能和创面的辨证关系。同时，不能忽视外科营养在过程中的重要作用，它是创面修复的物质保证。     

Glutamine supplementation in vitro and in vivo,in exercise and in immunodepression

In situations of stress, such as clinical trauma, starvation or prolonged, strenuous exercise, the concentration of glutamine in the blood is decreased, often substantially. In endurance athletes this decrease occurs concomitantly with relatively transient immunodepression. Glutamine is used as a fuel by some cells of the immune system. Provision of glutamine or a glutamine precursor, such as branched chain amino acids, has been seen to have a beneficial effect on gut function, on morbidity and mortality, and on some aspects of immune cell function in clinical studies. It has also been seen to decrease the self-reported incidence of illness in endurance athletes. So far, there is no firm evidence as to precisely which aspect of the immune system is affected by glutamine feeding during the transient immunodepression that occurs after prolonged, strenuous exercise. However, there is increasing evidence that neutrophils may be implicated. Other aspects of glutamine and glutamine supplementation are also addressed.     

Sex differences in neuromuscular fatigability in response to load carriage in the field in British Army recruits

Objectives

Women are resistant to neuromuscular fatigue compared to men in response to a range of exercise tasks. The sex differences in the neuromuscular responses to load carriage have yet to be investigated.

Decrease in eccentric hamstring strength in runners in the Tirol Speed Marathon

Background

The local muscular endurance of knee flexors, during eccentric work in particular, is important in preventing or delaying kinematic changes associated with fatigue during treadmill running. This result, however, may not be transferable to overground running.

Objective

To test the hypothesis that overground running is associated with eccentric hamstring fatigue.

Methods

Thirteen runners (12 male and one female) performed an isokinetic muscle test three to four days before and 18 hours after a marathon. Both legs were tested. The testing protocol consisted of concentric and eccentric quadriceps and hamstring contractions.

Results

There were no significant differences between peak torque before and after the race, except that eccentric peak hamstring torque (both thighs) was reduced.

Conclusion

Overground running (running a marathon) is associated with eccentric hamstring fatigue. Eccentric hamstring fatigue may be a potential risk factor for knee and soft tissue injuries during running. Eccentric hamstring training should therefore be introduced as an integral part of the training programme of runners.     

Oxalosis in primary hyperoxaluria in infancy

Primary hyperoxaluria (PH1) is a rare inborn autosomal recessive metabolic disorder due to the deficiency of hepatic alanine-glyoxylate-aminotransferase. This deficiency results in excessive synthesis and urinary excretion of oxalate, inducing renal stone formation and deposition of calcium oxalate in the kidney, bone, myocardium, and vessels (systemic oxalosis, SO) in the most severely affected individuals. We report renal and skeletal changes in a 3-month-old girl with PH1 and SO. Intense cortico-medullary hyperechogenicity and increased homogeneous radiopacity of normal-sized kidneys suggested the diagnosis of SO. Skeletal survey showed osteopenia and characteristic symmetrical metaphyseal transverse bands in long bones, progressively becoming more dense and migrating towards the diaphysis. Multiple pathological and slowly healing fractures of the limbs occurred at the dense band level. A radiopaque rim was then observed in flat bones, epiphyseal nuclei, and vertebral bodies. Inflammatory granulomatous reaction, induced by the presence of oxalate crystals in the marrow spaces, coexisted with progressively evident radiological signs of secondary hyperparathyroidism, with partially overlapping features. The patient was treated by peritoneal dialysis and hemodialysis until combined liver–kidney transplantation. There are no previous reports of infants treated with hemodialysis for more than 2 years.     

新疆石河子地区奶牛隐性乳房炎的调查与分析

采用LMT法对新疆石河子地区三个规模化奶牛场泌乳牛群进行了隐性乳房炎检测,共检测994头泌乳牛3976个乳区.结果表明:奶牛隐性乳房炎阳性率为81.9%,乳区阳性率为49.1%.数据分析表明,不同年龄、胎次以及有无卧床奶牛的隐性乳房炎阳性率差异显著(P<0.05),后乳区的隐性乳房炎感染率显著高于前乳区感染率(P<0.05),隐性乳房炎乳区发生数也明显影响当日产奶量(P<0.05).     

肺心病慢性呼吸性酸中毒合并代谢性酸碱失衡判断方法探讨(附80例次血气分析)

目的：对42例肺心病慢性呼吸性酸中毒患者的80例次血气测定结果。方法：用不同的酸碱图（卡）及代偿公式进行酸碱类型的初步差别分析。结果：结合临床表现、各种影响因素与治疗反应等作出综合判定。结论：比较二种判定的差异，并提出较为实用、可靠的判断建议，以助于复合型呼吸性酸碱失衡的临床诊断与处理。     

胎龄和日龄对新生儿局部脑血流的影响

目的探讨胎龄及日龄对新生儿局部脑血流(rCBF)变化的影响及规律.方法对早产儿组、足月早期新生儿组、足月晚期新生儿组进行99Tcm-双半胱乙酯(ECD)SPECT脑血流灌注断层显像,并作半定量分析和读片分析.结果早产儿组原始感觉运动区和枕叶rCBF低于足月早期新生儿组(P<0.05),显著低于足月晚期新生儿组(P<0.01),其额叶中份、顶叶rCBF也低于足月晚期新生儿组(P<0.05),其余各叶皮质rCBF随胎龄和日龄的增大有增加趋势.早产儿组脑血流显像图与足月早期新生儿组和晚期新生儿组比较有明显差异.结论早产儿与足月儿rCBF的变化可能与新生儿大脑皮质相应区域发育成熟度和时间顺序有关.     

Radiological strategy in acute stroke in children

The aim of the study was to estimate the preponderance of patterns of pediatric stroke, ischemic or hemorrhagic, their etiologies and the correct diagnostic protocol for acute management.Forty-one consecutive pediatric patients (age range 5-16 years) with an acute stroke observed in acute phase during a 10-year period, were retrospectively evaluated. Twenty-three patients underwent magnetic resonance imaging (MRI), 3 cases were studied by computed tomography (CT) without MRI, and 15 underwent both CT and MRI studies. In 9 cases, intra-arterial digital subtraction angiography (IADSA) was performed after non-invasive preliminary assessment.Seventeen hemorrhagic (41%) and 24 ischemic (59%) strokes were found. Among hemorrhagic forms, 5 cases were due to arteriovenous malformation (AVM), 7 to cavernoma, and 2 to aneurysm. Among ischemic forms, 2 were due to sickle-cell disease, 1 to hyperomocysteinemia, 1 to moyamoya syndrome, 1 to pseudoxantoma elasticum, 3 to prothrombotic state, 1 to Fabry's disease, 1 concomitant with CO intoxication, 5 to venous sinus thrombosis, and 4 to cardio-embolic state. Etiology remains unknown in 8 cases (20.5%).This study shows a moderate prevalence of ischemic over hemorrhagic strokes. Moreover, personal experience suggests that MRI is always more informative than CT and in selected cases should be the first-choice examination in the acute phase.