Blood flow velocity in the common carotid artery in humans during graded exercise on a treadmill

Cerebral blood volume flow and flow velocity have been reported to increase during dynamic exercise, but whether the two increase in parallel and whether both increases occur as functions of exercise intensity remain unsettled. In this study, blood flow velocity in the common carotid artery was measured using the Doppler ultrasound method in eight healthy male students during graded treadmill exercise. The exercise consisted of stepwise progressive increases and decreases in exercise intensity. The peak intensity corresponded to approximately 85% of maximal oxygen consumption. During this exercise, the heart rate (f _c), mean blood pressure (BP) in the brachial artery and mean blood flow velocity (_cc) in the common carotid artery increased as functions of exercise intensity. At the peak exercise intensity, (f _c), BP and _cc increased by 134.5%, 20.5% and 51.8% over the control levels before exercise (P < 0.01), respectively. The resistance index (RI) and pulsatility index (PI) were determined from the velocity profile and were expected to reflect the distal cerebral blood flow resistance. The RI and PI increased during the graded exercise, but tended to decrease at the highest levels of exercise intensity. As _cc increased with increases in exercise intensity it would be expected that cerebral blood flow would also increase at these higher intensities. It is also suggested that blood flow velocity in the cerebral artery does not proportionately reflect the cerebral blood flow during dynamic exercise, since the cerebral blood flow resistance changes.     

神经生长颗粒对大鼠腓总神经横断损伤的修复作用

目的 研究神经生长颗粒(NGG)对大鼠腓总神经横断损伤的修复作用.方法 SD大鼠50只,随机分为NGG高、中、低剂量组(剂量分别为5.2g生药/kg、2.6g生药/kg、1.3g生药/kg)、弥可保组(剂最为625μg/kg)、空白对照组.行大鼠腓总神经横断缝合术,术后每日灌胃给药.于术后2周、3周、4周行足迹实验,测定展趾功能,术后4周行电生理检测,测定复合肌动作电位和神经干动作电位检测,组织形态学分析,测定再生有髓神经纤维数、髓鞘厚度和胫前肌肌纤维截面积,观察NGG对大鼠腓总神经损伤的修复作用.结果 与空白对照组相比,NGG组展趾功能、复合肌动作电位和神经干动作电位波幅及恢复率、再生有髓神经纤维计数、髓鞘厚度及胫前肌横截面积均显著增高,且呈剂量依赖的量效关系.结论 NGG有利于轴突生长和髓鞘形成,可以促进大鼠损伤神经修复和神经功能的恢复.     

Chitooligosaccharides protect cultured hippocampal neurons against glutamate-induced neurotoxicity

Chitooligosaccharides (COSs), the biodegradation product of chitosan, have demonstrated a diverse array of biological activities. Here we report the protective effect of COSs (M.W. 800) against glutamate-induced neurotoxicity in cultured hippocampal neurons. The cell viability assessments, together with Hoechst 33342 staining and flow cytometry for cell apoptosis analysis, indicated that glutamate (125 μM)-induced cell apoptosis in cultured hippocampal neurons was attenuated in a concentration-dependent manner by COSs pretreatment. After measurement with Fluo 4-AM, COSs were found to depress glutamate-induced elevation in intracellular calcium concentration ([Ca²⁺]_c). The enzymatic assay indicated that COSs antagonized glutamate-evoked activation of caspase-3. These results collectively suggest that COSs prevent cultured hippocampal neurons from glutamate-induced cell damage by interfering with an increase in [Ca²⁺]_c and inhibiting caspase-3 activity.     

神经生长因子对穹窿海马伞切割后海马自体神经干细胞增殖和向神经元分化的影响

目的 探讨切割穹窿海马伞及脑室给予神经生长因子(NGF)后,对大鼠海马自体神经干细胞增殖和分化为神经元的影响.方法 12只SD大鼠,随机分成给药组和对照组,每组6只,切割右侧穹窿海马伞,两组切割后即时及第2d、4d向侧脑室分别注射NGF和人工脑脊液, 并在术后第3～7d每日腹腔注射2次BrdU.于术后28d灌注取脑、冷冻切片,行BrdU/NF-200免疫荧光双标检测.结果 海马齿状回内BrdU阳性细胞数,给药组和对照组切割侧明显多于正常侧,给药组切割侧和正常侧分别多于对照组切割侧和正常侧;海马齿状回内的BrdU/NF-200双标神经元数,给药组切割侧最多,给药组正常侧和对照组切割侧较少,而对照组正常侧则无.结论 切割穹窿海马伞后,可致大鼠海马齿状回自体神经干细胞增殖加快并向神经元分化,脑室施加 NGF可促进其增殖和分化.     

运用品管圈提高血药浓度监测及个体化服务项目的认可度

目的提高血药浓度监测(TDM)及个体化服务项目的认可度。方法2019年1—7月,针对TDM每月监测例数较低,针对医生进行问卷调查,按品管圈的10个步骤实施各项活动,并对活动成果进行评价。结果明确了影响TDM监测例数低的因素,通过品管圈活动拟定了一系列对策,有形成果方面,每月监测例数逐步提高;无形成果方面,圈员的品管手法、解决问题能力、责任心都有不同程度的提升。结论品管圈活动显著提高了血药浓度监测及个体化服务的认可度。     

伤病比在医院维权中的运用

为了保证民法的公平原则,避免医疗纠纷赔偿案件审理中忽视患者本身病情所致的不良后果的情况,对损伤与疾病对患者预后的影响进行了研究.介绍了伤病比的来源,论述了伤病比在医疗纠纷处理中的适用 范围,伤病比的级别与医院承担的赔偿额度.指出应增强伤病比意识,促进医与法的完美结合.     

效率:素质教育评价的至重砝码

教育评价、教育目标、教育活动是现代教育教学系统三大因素。构建科学的素质教育评价体系应提到战略高度来认识和解决。“高效”是素质教育的“特质” ,实现“高效化”是实施素质教育的必由之径。素质教育的“效率”是“投入”与“产出”之比 ,其投入包括时间、物力、人力、脑力等投入 ,其“产出”也是一个动态的结构系统     

Immunohistochemical analysis of the vimentin filaments in Sertoli cells is a powerful tool for the prediction of spermatogenic dysfunction

The close interaction between male germ cells and Sertoli cells, a type of somatic cell found in the seminiferous tubules of mammalian testis, is essential for the normal progression of spermatogenesis in mammals. Vimentin is an intermediate filament protein that primarily provides mechanical support, preserves cell shape, and maintains the nuclear position, and it is often used as a marker to identify Sertoli cells. Vimentin is known to be involved in many diseases and aging processes; however, how vimentin is related to spermatogenic dysfunction and the associated functional changes is still unclear. In a previous study, we reported that vitamin E deficiency affected the testes, epididymis, and spermatozoa of mice, accelerating the progression of senescence. In this study, we focused on the Sertoli cell marker vimentin and explored the relationship between the cytoskeletal system of Sertoli cells and spermatogenic dysfunction using testis tissue sections that caused male reproductive dysfunction with vitamin E deficiency. The immunohistochemical analysis showed that the proportion of the vimentin-positive area in seminiferous tubule cross-sections was significantly increased in testis tissue sections of the vitamin E-deficient group compared with the proportion in the control group. The histological analysis of testis tissue sections from the vitamin E-deficient group showed that vimentin-positive Sertoli cells were greatly extended from the basement membrane, along with an increased abundance of vimentin. These findings suggest that vimentin may be a potential indicator for detecting spermatogenic dysfunction.     

银杏内酯抗过氧化氢致神经细胞损伤和对即早基因表达的影响

目的 :探讨银杏内酯 (ginkgolides ,Gin)对过氧化氢 (H2 O2 )诱导的皮层神经细胞损伤的保护作用及其机制。方法 :在小鼠皮层神经细胞的培养基中加入H2 O2 ,建立神经细胞氧化损伤模型 ,利用MTT比色法检测细胞存活率 ,Westernblot技术分析c fos、c jun基因表达产物C FOS蛋白、C JUN蛋白的变化。结果 :H2 O2 可诱导原代培养的神经细胞损伤和存活率降低 ,其损伤作用呈现浓度和时间依赖性 ;同时可诱导神经元C FOS、C JUN表达增加。Gin预处理2 4h可明显减轻神经细胞形态学改变 ,提高神经细胞存活率 ,且在 0～ 37.5mg·L-1范围内呈现浓度依赖关系。Gin能明显逆转H2 O2 诱导的C JUN蛋白表达的增高 ,对H2 O2 刺激的C FOS蛋白表达无明显影响。结论 :Gin可对抗H2 O2 引起的神经细胞损伤 ,该保护作用与其抑制细胞c jun基因过度表达有关。     

雌激素干预影响腹腔脂肪积聚的实验研究

目的研究雌激素干预对雌性C57BL/6J小鼠腹腔脂肪代谢的影响.方法采用卵巢切除法造成雌激素缺乏模型,以及在动情周期正常和围绝经期的小鼠中,给以雌激素干预,观察腹腔脂肪重量的变化.3 mon 龄小鼠随机分为正常组,卵巢切除组,给雌激素 15 d 组和给雌激素 60 d 组,每组10只.小鼠摘除卵巢后饲养至 7 mon 龄处死.5和 10 mon 龄小鼠分为正常组,动情周期正常+雌激素 60 d组,围绝经期组和围绝经期+雌激素 60 d 组,每组10只,分别饲养至7和 12 mon 龄处死,检测腹腔脂肪重量.各组小鼠于处死前15和 60 d 分别皮下埋植控释雌激素(17β-雌二醇)药丸(0.18 mg/丸).结果卵巢切除组腹腔脂肪重量明显增加(P<0.05);给雌激素 15 d 组腹腔脂肪重量减轻(P＜0.05);给雌激素 60 d 组腹腔脂肪重量有明显减轻,与正常组比较无显著性差别(P>0.05).动情周期正常+雌激素组和围绝经期+雌激素组的小鼠,其腹腔脂肪重量的变化无差别.结论卵巢切除明显影响小鼠的脂肪代谢导致腹腔脂肪积聚,而雌激素干预,特别是长期应用,可以明显减少小鼠的腹腔脂肪积聚.外源性雌激素干预在动情周期正常和围绝经期对小鼠腹腔脂肪没有明显的影响.