孕妇妊娠晚期和妊高征患者血小板参数的分析

目的观察正常孕妇妊娠晚期和妊高征患者血小板参数的变化及临床意义。方法采用日本Sysmex KX-21型血液细胞分析仪分别对正常孕妇（118例）、妊高征患者（59例）及对照组（正常婚检妇女59例）的血液标本进行血小板（PLT）计数、平均血小板体积（MPV）、血小板分布宽度（PDW）的测定。结果妊高征组和正常孕妇组的MPV、PDW显著高于对照组（P〈0.01）;妊高征组MPV、PDW明显高于正常孕妇组（P〈0.05）;妊高征组的PLT显著低于对照组（P〈0.01）。结论妊高征患者由于血小板消耗和破坏增加,导致血小板减少,MPV、PDW明显增高,因此,检测血小板参数对预测妊高征的发生有一定的参考意义。     

The effects of amrinone and glucagon on verapamil-induced cardiovascular toxicity in anaesthetized rats

The goal of this study was to compare the effects of glucagon and amrinone on mean arterial pressure (MAP) and heart rate, when used alone and in combination, in an anaesthetized rat model of verapamil toxicity. Rats were anaesthetized and the carotid artery was cannulated for MAP and heart rate measurements. Jugular and femoral veins were cannulated for drug administration. After verapamil infusion (15 mg/kg/h), control animals were given normal saline solution and the other groups received amrinone (0.1 or 0.2 mg/kg/min), glucagon (0.3 mg/kg bolus followed by 0.1 or 0.2 mg/kg/min infusion), glucagon plus amrinone (0.1 mg/kg/min and 0.1 mg/kg/min respectively) or glucagon plus amrinone (0.2 mg/kg/min and 0.1 mg/kg/min respectively). Glucagon (0.2 mg/kg/min) significantly increased MAP when compared to the control group ( P  < 0.01). The combination of glucagon and amrinone did not produce a synergistic effect for the recovery of MAP. Furthermore, this combination masked the positive effects of glucagon (0.2 mg/kg/min) on MAP.Glucagon (0.2 mg/kg/min) increased the heart rates compared with those of the control group ( P  < 0.05). Additionally, amrinone (0.1 mg/kg/min) plus glucagon (0.1 mg/kg/min) increased the heart rates ( P  < 0.05). Finally, glucagon dose dependently recovered MAP. While amrinone depressed MAP in combination with glucagon, it did not alter the positive chronotropic effect of high dose glucagon.     

Hitting moving objects: is target speed used in guiding the hand?

We investigated what information subjects use when trying to hit moving targets. In particular, whether only visual information about the target's position is used to guide the hand to the place of interception or also information about its speed. Subjects hit targets that moved at different constant speeds and disappeared from view after varying amounts of time. This prevented the subjects from updating position information during the time that the target was invisible. Subjects hit further ahead of the disappearing point when the target moved faster, but not as much as they should have on the basis of the target's speed. This could be because more time is needed to perceive and use the correct speed than was available before the target disappeared. It could also be due to a speed-related misperception of the target's final position. The results of a second experiment were more consistent with the latter hypothesis. In a third experiment we moved the background to manipulate the perceived speed. This did not affect the hitting positions. We conclude that subjects respond only to the changing target position. Target speed influences the direction in which the hand moves indirectly, possibly via a speed-related misperception of position.     

Hypotension and thirst in rats after isoproterenol treatment

Drinking induced in rats by systemic isoproterenol treatment is markedly attenuated after bilateral nephrectomy. The present experiments demonstrate that the hypotension produced by iso-proterenol treatment was more profound, and lasted much longer, in nephrectomized rats than in intact animals. When arterial blood pressure was partially elevated by central administration of angiotensin II or carbachol (Experiment 1) or by intraarterial infusion of epinephrine (Experiment 2), drinking behavior was restored in the nephrectomized animals and their water intakes approximated the amounts consumed by intact rats given isoproterenol. In general, an inverted U-shaped curve was found to define the relation between blood pressure and water intake in rats after isoproterenol treatment. Drinking was most probable when mean arterial blood pressures were in the range of 70–85 mm Hg, whereas rats were unlikely to drink when blood pressures were much below or above this range. These findings indicate that isoproterenol-induced thirst is not dependent on a renal dipsogen, and suggest instead that the hypersecretion of renin that occurs in intact rats is simply permissive of drinking behavior by modulating the hypotensive effects of the drug treatment.     

Pitfalls in acid/base experiments with conscious dogs

Arterial pH and blood gases were measured at intervals in conscious dogs after their first human contact of the day. Blood was sampled through an indwelling catheter in the aorta without disturbing the animals. It appeared that in the first 90 min arterial PO₂, oxygen saturation and haemoglobin concentration significantly declined. PCO₂ and pH changed less consistently when the acid/base status of the dogs was normal, but when a non-respiratory acidosis was present there was a significant decrease in pH and a significant increase in PCO₂. Arterial pH and blood gases were also measured before and after feeding the animals. It appeared that an appreciable metabolic alkalosis developed within 2 h after a meal. The alkaline tide was accompanied by a trend to higher values for PCO₂. It is concluded that, after a period of seclusion, renewed human contact causes behavioural changes in a dog, which may result in appreciable transitory changes in arterial pH and blood gas values. Blood sampling from conscious dogs should therefore take place after a proper period of habituation; preferably, a few samples should be taken at intervals to check that a steady state has been reached. If possible, blood should be collected before feeding; in any case the relationship in time of blood sampling to feeding should be constant throughout.     

肝纤维化门静脉压力改变与血清ET-1/NO关系的实验研究

目的制作兔肝纤维化模型，观察血管活性物质与门静脉压力变化的关系。方法40只家兔采用口服硫代乙酰胺方法造模，分别于造模第8、12、16、20周时检测内皮素（ET-1）及NO浓度，超声观察胆囊壁及肝脏血流动力学指标，直接穿刺测量不同时期门静脉压力。分析血管活性物质与肝脏血流动力学指标及门静脉压力变化间的关系。结果胆囊壁增厚是肝纤维化阶段的二维超声表现；随着纤维化程度的加重，血清ET-1、NO浓度逐渐增加，且以ET-1／N0比值增加更为明显；门静脉内压力、肠系膜上动脉、脾动脉搏动指数（PI）随纤维化程度逐渐增加，实验组与对照组间差异有统计学意义（P〈0．05），且与ET-1／NO值呈正相关（P〈0．01）。结论通过超声可无创检测肝脏血流动力学变化，对肝纤维化临床诊断及治疗效果的观察，具有积极的作用。     

Control of single-joint movements in deafferented patients: evidence for amplitude coding rather than position control

Two deafferented patients and several control subjects participated in a series of experiments to investigate how accurate single-joint movements are programed, spatially calibrated, and updated in the absence of proprioceptive information. The deafferented patients suffered from a permanent and severe loss of large sensory myelinated fibers below the neck. Subjects performed, with and without vision, sequences of forearm supinations and pronations with two temporal delays between each movement (0 s and 8 s). Overall, the lack of proprioception did not yield any significant decrease in movement accuracy when vision was available. Without vision, the absence of proprioceptive afferents yielded (1) significantly larger spatial errors, (2) amplitude errors similar to those of control subjects, and (3) a significant drift when an 8-s delay was introduced between two successive movements. Subjects also performed, without vision, a 20 supination followed by a 20 pronation that brought back the wrist to the starting position. On some trials, the supination was blocked unexpectedly by way of a magnetic brake. When the supination was blocked, subjects were already on the second target and no pronation was required when the brake was released. The defferented patients, unaware of the procedure, always produced a 20 pronation. These data confirm that deafferented patients were not coding a final position. It rather suggests that they coded an amplitude and translated the spatial distance between the two targets in a corresponding force pulse. Overall, the results highlight the powerful and key role of proprioceptive afferents for calibrating the spatial motor frame of reference.     

Responsiveness of the ANP providing system to volume load in conscious dogs

We examined in detail changes in arterial plasma ANP concentration in response to volume load in conscious dogs. In a 5-min volume load experiment, 18 ml/kg of isosmotic and isooncotic 3% Dextran 40 in saline was infused over a period of 5 min. Mean left atrial pressure (MLAP) increased transiently by 7.6±0.9 mm Hg. Plasma ANP level (P-ANP) did not significantly increase. Assayed P-ANP levels were corrected for hemodilution. Corrected P-ANP (C-ANP) significantly increased from 206±17 to 348±34 pg/ml. However, the level of C-ANP did not reach a steady state. No significant linear correlation was found between increases in MLAP and normalized C-ANP. In a 45-min volume load experiment, the elevated level of MLAP caused by the 5-min volume load was maintained for 40 min by supplemental infusion. C-ANP significantly increased from 196±18 pg/ml to 435±73 ng/ml. The level of C-ANP reached a steady state. A close linear correlation was observed between increases in MLAP and normalized C-ANP. However, the peak time of C-ANP lagged 10 min behind MLAP. These results indicate that it takes 10 min for P-ANP to reach a steady state in fully responding to a volume load, and that the long-term volume load is a prerequisite to the response of the ANP providing system.     

The Effects of Menstrual Cycle Phase on Cardiovascular and Pulmonary Responses to Behavioral and Exercise Stress

The present study was designed to compare the differential cardiopulmonary and hemodynamic responses of Type A and B women to an exercise and a psychological stressor. In addition, the effects of menstrual cycle phase on the resting and response levels of a wide range of physiological variables were explored. Thirty-two women participated in a progressive exercise stress test and a threat of shock video game during both the luteal and follicular phases of the menstrual cycle. Half of these subjects expressed the coronary-prone behavior pattern referred to as Type A, as assessed by the Jenkins Activity Survey. The remaining women were relatively free of these behaviors (Type B). Heart rate, oxygen consumption, carbon dioxide production, minute ventilation, and end-tidal carbon dioxide were monitored and recorded on a breath-by-breath basis. Systolic and diastolic blood pressure measures were taken at 2-min intervals. Results indicated similar baseline, exercise, and behavioral stress responses among Type A and B women. The stress responses were also the same between the follicular and luteal phases for all measured physiological variables. However, resting levels of heart rate, metabolism, and ventilation were all elevated at rest during the luteal phase. A regression analysis based on the exercise heart rate and oxygen consumption data demonstrated that a majority of subjects exhibited heart rate responses in excess of that expected during the psychological stressor. These data are discussed with special reference to possible mechanisms of the pathophysiology of cardiovascular disease.     

茶色素治疗糖尿病前后血液流变性和微循环检测分析

目的：观察茶色素治疗糖尿病前后血液流变微循环的变化。方法：糖尿病人88例，男71例，女17例，年龄32～64岁。口服茶色素2粒（250mg），每日3次，疗程为30天。结果：血液流变学参数、微循环积分值、血生化指标、RIA都有明显改善（P＜0．01或P＜0．05）。结论：茶色素可以明显改善糖尿病人血液流变性和微循环多项检测指标，值得临床推广应用。