Ethanol regulated preference in rats

A series of experiments evaluated the determinants of preference for mixtures of ethanol plus sucrose relative to sucrose in rats. One dipper served 10% ethanol mixed with 10% sucrose, and the second dipper served 10% sucrose. Lever presses operated each dipper according to a variable-interval 5-s schedule. In three experiments the subjects were given pre-session meals of sucrose (2.5–20 ml) or sucrose (20 ml) plus chow (5 or 10 g). Pre-session meals decreased responding maintained by sucrose but not responding maintained by ethanol mixture. In two experiments body weight was varied from 85% to 125% of the initial free-feeding values. Increases in body weight, like pre-session meals, decreased responding reinforced by sucrose, but typically did not decrease responding reinforced by ethanol mixture. Throughout most of the study, ethanol consumption remained at about 1.25 ml per half hour session (3–4 g/kg per 30 min). For example, pre-session access to ethanol mixture decreased within-session ethanol consumption, but total consumption, counting both sources, remained about 1.25 ml/session. The within-session patterns of responding also differed. Responding reinforced by ethanol mix decreased as a function of ethanol consumption, whereas responding reinforced by sucrose was relatively constant throughout the session. The simplest explanation of the results is that ethanol's pharmacological consequences regulated preference.     

实验性尘细胞灶与胸片细网状阴影形成的关系

本文从21只实验性矽肺家兔中筛选出5只胸片有细网状阴影者,用病理与 X 线对照观察的方法,探讨了实验性矽肺尘细胞灶与死后胸片细网状阴影形成的关系。证明,分布在肺细叶内直径约1mm 的尘细胞灶,其分布密度为113个/cm~2以上时,可构成胸片细网状阴影。实验排除了弥漫性肺间质纤维化的结论。并对胸片细网状阴影的形成从肺细叶解剖与 X 线投影进行了讨论。     

A rat model of monitoring liver allograft rejection

Rat models are often used to study liver allograft rejection. We have established a model for rat liver allograft rejection, monitored by fine needle aspiration biopsy (FNAB), in the strain combination PVG-to-BN with a mean survival time of 37 ± 20 days. In this model, we observed acute rejection with an intense peak of lymphoid blasts and lymphocyte-dominated inflammation in the FNAB [9.1 ± 3.0 corrected increment units (CIU)], and an eventual increase in macrophages (up to 4.2 ± 4.4 CIU), together with fibrosis and parenchymal necrosis in the graft. Markers of immune activation, such as an increase in IL-2-receptor (from 1 % ± 2 % to 21 % ± 13 %) and class II (from 20 % ± 9 % to 43 % ± 13 %) expressing lymphoid cells and induction of ICAM-1 in the graft, were consistent with the overall cellular response. The FNAB correlated well with parallel graft histology. In this rat model, the atraumatic monitoring makes a close follow-up possible without having to sacrifice the experimental animals. This saves work, animals, and costs in the study of liver rejection. Received: 2 July 1996 Accepted: 28 October 1996     

缩窄门静脉主干1／2加丝线慢性栓塞术制备犬门静脉高压症模型

目的:探索操作简便且效果满意的门静脉高压症动物模型制备方法.方法:缩窄门静脉主干1/2加丝线慢性栓塞术,通过22条犬进行实验.结果:除1条死亡外.其余21条术后3～4周时门静脉压力升高至2.83±0.66kPa(术前1.33±0.28kPa,P<0.001):胃镜、门静脉造影及病理学检查证实,17条犬有食管胃底曲张静脉形成,形成率80.95%(其中方法完善后制备的14条、形成率100%),12条发生门脉高压性胃病,发生率57.14%.1条观察至术后4月.门静脉高压症表现仍然存在.结论:该法简便易行、建立模型周期短、成功率高且质量可靠并较持久.     

过度训练的病理生理及康复 Ⅰ.大鼠过度训练模型的建立

实验表明,运用大鼠跑台运动,以心电图、体重、饮食量、精神状况、毛发脱落、尿蛋白、血清睾酮、皮质醇等为监测指标建立大鼠过度训练模型的方法是可行的。本文并首次模拟出大鼠运动性心律失常心电图。     

Model parameters of the smooth pursuit eye movement system with electrooculogram

The visual pursuit test is a method that collects and analyzes the characteristics of pursuit eye movements and examines the function of the eye movement system. This paper analyzes the model parameters of the smooth pursuit eye movement system in order to explore a method for improving the analysis. The input-output relationship of the smooth pursuit system can be expressed by a quasilinear model. We compute the model parameters (gain, phase, spectral purity, cross covariance) by digital signal processing. Eye movement is recorded by electrooculogram. Both eyes are tested individually. The visual target moves at frequencies of 0.2, 0.4, 0.8, 1.2, and 1.6 Hz. Ranges are gain, 1.01 to 0.70; phase, -0.1 ° to -66 °; spectral purity, 0.97 to 0.70; and cross covariance, 0.99 to 0.26. We tested 40 normal subjects as well as patients with ataxia (8), vertigo (18), and ophthalmoplegia (9). The oculomotor system of normal subjects functions as a linear system in the performance of this test at 0.2 to 0.8 Hz. The spectral purity dropped to about 0.70 at 1.6 Hz. The variability of all measures increases greatly at 1.6 Hz, which indicates that this target motion exceeds the tracking ability of many normal subjects and that the oculomotor system of normal subjects functions as a nonlinear system in this condition. Statistical tests show no significant differences between sex, age, and the two eyes. The model parameters tentatively proved effective in clinical application.     

"吃食堂"的认知生成机制

以认知语法的行为链模式为分析工具,就汉语中的表工具、处所、方式等题元的介词宾语移位至动词宾 语位置的“吃食堂”等句法现象的成因作认知方面的解释说明。     

A novel access method for endovascular procedures in the porcine model

Objective To evaluate the use of the saphenous artery as an alternative access for endovascular procedures in the porcine model. Methods Fourteen adult pigs (25-35kg) were used in this study, 3 pigs from an acute study and 11 from chronic studies. A 2-3 cm incision was made and a saphenous artery cutdown was performed in 24 sides. Micropunc ture sets (Boston Scientific) or 18 G puncture needles were used to access the artery. Different sizes of introducers (4-7F) were used to establish endovascular access. Angiographic catheters were then used to confirm if the access was usable. Four saphenous arteries were explanted in the pigs from a chronic study 4 to 28 days after surgical procedure. Results The saphenous artery was very easy to expose and 4-5 F introducer sheaths were able to be inserted to establish access for endovascular procedures in the pigs. The saphenous artery was unable to accomodate an introducer with a size larger than 6 F. Four saphenous arteries were injured when 5 and 6 F introducers were used, but angiographic procedures could still be performed. Morphologic evaluation of the explanted arteries demonstrated occlusion of the saphenous arteries without injury or disruption of the adjacent femoral arteries. Conclusion The saphenous artery can be used as an access site in pigs for angiographic and interventional procedures if the catheter size is less than 6 F. This vessel is easier to access and can preserve the femoral artery for repeat procedures in the future.     

一种稳定的急性胰腺炎胰腺外多器官损伤大鼠模型

目的研究一种病理进程平稳的急性胰腺炎胰腺外多器官损伤动物模型.方法应用小剂量中等浓度胆盐、胰管内低压注射的方法,动态观察实验大鼠胰腺、肺、肝脏及肾脏的功能和病理改变.结果这种新的急性坏死性胰腺炎大鼠模型具有胰腺外持续、稳定的肝、肾损伤.结论这种急性坏死性胰腺炎大鼠模型适合于多器官功能损伤的病理机制及治疗学研究.     

温敏性聚(N-异丙基丙烯酰胺)水凝胶的合成与表征

作者根据高等教育评价的有关理论与方法，采用“学生评教”的方式，在教学评价这一层次上运用微观多因素定量与定性相结合的评价方法对23门医学硕士研究生基础理论课、专业基础课和科研新方法课程的教学质量进行评价，从学生、教师和课程等方面研究影响教学质量的因素，同时对学校研究生过程培养的追踪提供一个参考方法和手段。