4种膜组件对黄连解毒汤膜过滤过程的比较研究

目的:以中药复方黄连解毒汤为实验对象,比较FMX旋转圆盘平板、中空纤维、管式、过滤杯4种膜组件的膜过滤过程.方法:在相同实验操作条件下,从膜过滤通量、膜阻力分布、指标性成分透过性、膜污染等多个方面,比较4种膜组件对黄连解毒汤的膜过滤情况.结果与结论:FMX、中空纤维、管式膜组件3种动态过滤形式的膜组件比静态死端过滤形式的过滤杯膜组件,在膜通量、膜污染度、指标成分透过性方面具有较为明显的优势;而使流体呈现强烈涡旋状态的FMX膜组件在膜通量、膜污染方面义比管式、中空纤维膜组件具有优势.     

低温预处理对大鼠脊髓损伤早期病理形态学的影响

目的观察低温预处理对大鼠脊髓损伤早期病理形态学的影响。方法采用改良Allen氏打击法建立大鼠脊髓损伤模型,损伤前应用局部脊髓低温灌注给予低温预处理,采用HE染色观察脊髓损伤早期病理形态学改变,Hplas-100病理图文分析系统对脊髓损伤中心区残留白质面积进行定量分析。结果实验组脊髓损伤早期病理形态学改变较对照组轻,损伤中心区残留白质面积大于对照组,差异有统计学意义（P〈0.01）。结论低温预处理对大鼠正常脊髓形态结构无明显影响,可明显减轻大鼠脊髓损伤早期病理形态学损害,减少损伤中心区白质面积的丢失。     

退热贴微生物限度检查方法的验证

目的建立退热贴微生物限度检查方法。方法参照《中国药典》2010年版微生物限度检查方法,采用常规法进行该药品的微生物方法学验证。结果采用常规平皿法时,大肠埃希菌、金黄色葡萄球菌、枯草芽孢杆菌、白色假丝酵母菌、黑曲真菌的回收率均高于70%,细菌、真菌和酵母菌计数采用常规平皿法,控制菌金黄色葡萄球菌、铜绿假单胞菌采用常规法检查。结论常规法可用于退热贴的微生物限度检查。     

Influence of vagal cooling on cardiac output in normal and beta-blocked exercising dogs

Summary To study the relative influence of parasympathetic and sympathetic innervation on the early adaptation of cardiac output (CO) to exercise, we determined the time constant and amplitude of the CO change in dogs following a stepwise increase in treadmill velocity. The animals were studied during control conditions, beta-blockade, vagal blockade and combined beta-blockade and vagal blockade. To measure CO, an electromagnetic flow probe was implanted around the ascending aorta. Vagal activity was blocked with coolers, implanted around the cervical vagosympathetic trunks.The time constant during beta-blockade (12.1 s) was not different from the control situation (11.4 s), but during vagal cooling it increased significantly (16.2 s), and with combined vagal cooling and beta-blockade it rose to 20.7 s. Thus the increase in cardiac output with exercise is accelerated most by the loss of vagal tone and to a lesser degree by sympathetic activation.The amplitude of the change in CO during control was 112%. Heart rate (HR) rose by 74% and stroke volume (SV) by 22%. Beta-blockade lowered the initial CO but did not alter the percentage increase. Vagal cooling, with or without beta-blockade, caused an increased initial HR but did not influence basal CO because of a concomitant reduction in SV. Exercise now increased HR less (21% and 30%, respectively) and SV more (52% and 52%) but the increase in CO did not change significantly (87% and 97%).Both the high percentage increase in CO (87%) and the time constant during combined beta-blockade and vagal blockade (20.7 s), which is far less than previously found in dogs with surgically denervated hearts (29.5 s), suggest the existence of a non-vagal, non-beta-adrenergic innervation of the heart.     

The projection of the nucleus reticularis tegmenti pontis and adjacent regions of the pontine nuclei to the central cerebellar nuclei in the cat

The projection of the nucleus reticularis tegmenti pontis (NRTP) and the pontine nuclei (NP) to the central cerebellar nuclei (CCN) was investigated by means of anterograde transport of tritiated leucine. Although termination was found in all the CCN, it was most pronounced in the lateral nucleus and the lateral aspect of the posterior interposed nucleus. The extreme lateral aspect of the anterior interposed nucleus and the caudal part of the fastigial nucleus received a projection of modest intensity. Termination in the infracerebellar nucleus and group Y is likely to be present but could not be confirmed with certainty from the light microscopical material. The contribution from the NP was small and originated from the dorsolateral and dorsal paramedian subdivisions of the NP. Within the NRTP the total area giving rise to projections to the CCN was extensive, and the origin of the projections to the individual CCN overlapped considerably. The projection of the NRTP to the ventrocaudal part of the lateral nucleus was found in conjunction with a projection to the ventrolateral part of the posterior interposed nucleus. Both projections seemed to branch off the fiber bundle terminating in the ventral paraflocculus. Similar correlations could be established in the projection of the NRTP to the dorsal paraflocculus and crus II of the ansiform lobule with other parts of the lateral and posterior interposed nuclei. It was concluded that the transverse, lobular organization of mossy fibers, which differs fundamentally from the longitudinal, modular organization of climbing fibers, is maintained in the collateral projection to the CCN. The results are further discussed in relation to the corticonuclear projection and the engagement of the NRTP and different parts of the CCN in pontocerebellar circuits.     

Global cerebral ischemia and subsequent selective hypothermia

Summary A new method of external selective brain cooling is described, showing its effectiveness in reducing neuronal damage following global cerebral ischemia in cat. The cooling apparatus consists of a specially fitted kind of water jacket in which the animal's head was laid. In a preliminary study it was verified that the device effectively reduces brain temperature without the risk of cardiac arrhythmias due to lowering of core temperature. In the main study cardiac arrest was induced in 23 adult cats, followed after 15 min by cardiopulmonary resuscitation (CPR). Eight cats could not be revived; of the 15 remaining animals, 7 were assigned to the control group (normothermia) and 8 to the treatment group (cerebral hypothermia). The latter received external brain cooling for 30 min, starting as soon as CPR was begun. Four hours after cardiac arrest all animals were transcardiacally perfused with glutardialdehyde. The brains were stored in fixative and subsequently processed for histopathological and morphometrical evaluation by light microscopy. Analysis of the resulting data showed that animals in the treatment group had a significantly higher percentage of undamaged neurons than animals in the control group, both in the cingulate gyrus (38% vs 10%) and in the parietal cortex (39% vs 14%). The treatment group also had more undamaged neurons in the hippocampus and fewer severely damaged neurons in all three regions, but these differences, though suggestive, were not statistically significant.     

Laser Resistance of Endotracheal Tubes II: ObservedTemperature Rise and Theoretical Explanation

An infrared camera was used to measure the temperature rise which takes place in endotracheal tubes exposed to a 20 W CO₂ laser beam. It was seen that a metallic tube was heated up within 1 s to temperatures of 200–300°C which was very destructive to the PVC conduits inside the tube. A compound tube, on the other hand, reached temperatures of only 60°C at its inner surface after an exposure of 20 s. The experimental results can be explained by a physical model which uses the heat conduction and the heat capacities of both tubes. Whereas heat conduction in the metal tube is isotropic, heat conduction in the compound tube is anisotropic with a high conductivity along the outer surface and a low conductivity to the inside. This anisotropy and the cooling mechanism in the compound tube due to vaporising water are the reason for the high laser resistance of the tube. Paper received 13 June 1997; accepted after revision 16 February 1998.     

The role of α<Subscript>1</Subscript>-and β-adrenoceptors in initiation and development of thermoregulatory reactions during fast and slow cooling

Ionophoretic application of α₁-and β-adrenoceptor blockers into the skin produces no effect on the parameters of thermal homeostasis under thermoneutral conditions. α₁-Adrenoblocker verapamil inhibits cold shivering during fast and slow cold exposure; it elevates the temperature threshold and moderates the vasoconstrictor response during rapid cooling. These changes are accompanied by a compensatory decrease in the threshold and stimulation of non-shivering thermogenesis. Application of non-selective β-blocker propranolol had no effect on the temperature thresholds of the thermoregulatory reactions, but augmented the maximum amplitude of shivering during both cooling protocols, thereby compensating the decrease in non-shivering thermogenesis. In the whole organism, block of one type adrenoceptors during cold exposure is accompanied by activation of the compensatory mechanisms mediated by adrenoceptors of the other type. __________ Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 145, No. 3, pp. 259–262, March, 2008     

静脉输冷液治疗过热家兔和狗的效果

将家兔和狗暴露于热环境,使动物肛温升至42.5℃(家兔)和43.0℃(狗)。实验动物分成4组,正常对照组(室温20～25℃),过热对照组(不治疗),输液对照组(静脉输32±0.3℃生理盐水)和输冷液组(家兔和狗分别静脉输1.2±0.34℃和2.0±0.1℃生理盐水)。实验结果表明,肛温的最大下降值,输冷液兔组为2.43℃,输冷液狗组为2.81℃,输液对照兔组为0.5℃,过热对照兔组肛温不下降,过热对照狗组下降1.1℃。输冷液动物的活存率显著比过热对照组和输液对照高。热损伤病理改变,输冷液组显著比过热对照组和输液对照组轻。