高张NaCl溶液对失血大鼠血压代偿的作用

使麻醉大鼠在5min 内失血,致使动脉血压下降至25mmHg,然后静脉注射1/10失血量的高张 NaCl 溶液(Hypertonic solution,HS,7.5%NaCl)或生理盐水(NS)。静脉注射少量 HS 能明显促进失血后血压回升,这个作用能为6-羟多巴胺或巯甲丙脯酸显著减弱,若将这两个药物同时应用,则 HS 的升压作用完全被解除。HS 使血浆 Na~+浓度明显升高,而 NS使之下降。侧脑室微量注射 HS 后也明显促进动脉血压的恢复。这些实验结果表明失血后静脉注射少量 HS 可升高血浆 Na~+浓度,高 Na~+作用于中枢神经系统,激活交感神经系统和肾素-血管紧张素系统,从而促使血压迅速恢复。     

An opioid antagonist stimulates myometrial activity in early postpartum cows

The influence of the opioid antagonist naltrexone on myometrial activity of cows was tested during the early postpartum period, when uterine contractions are a highly sensitive indicator of oxytocin actions. Registering intrauterine pressure oscillations in five first calf heifers revealed that myometrial activity was enhanced after naltrexone was administered (0.02 mg/kg BW). However, plasma concentrations of oxytocin were not consistently elevated. In addition, naltrexone did not reliably potentiate the suckling-induced peak of oxytocin release in plasma. In all cases, naltrexone injections caused increases in the cows' respiratory rates and distinct behavioral changes during the first days postpartum, but not later. We conclude that: 1) In the early postpartum period, an inhibitory opioidergic control of myometrial activity may exist in cattle. 2) This control does not seem to be caused by a change in circulating oxytocin levels. 3) Opioids may exert an inhibitory influence on respiratory functions in cattle.     

Seasonal variation in spontaneous intracerebral hemorrhage in northern Israel

The incidence of spontaneous intracerebral hemorrhage (sICH) and ischemic stroke vary across seasons. Most studies examining seasonal variation in sICH have been conducted in countries with significant climatic changes across seasons, whereas studies from the Mediterranean region, which has a relatively mild winter, are limited in number and have produced inconsistent results. Further studies from the region are called for, especially from countries where sICH seasonality has not yet been explored. A total of 974 patients with sICH between 1 January 2000 and 31 December 2014 were included in this study. The seasonal, monthly and weekday distribution of hospital admissions, in-hospital mortality, length of hospital stay and functional outcome at discharge were examined. We found that most hospital admissions due to sICH occurred in the winter (n = 286, 29%), whereas the fewest admissions occurred in the summer (n = 205, 21%; p = 0.0011). In terms of monthly distribution, most admissions were in January (n = 107, 11%), and the fewest admissions were in September (n = 60, 6%; p = 0.0004). There were no differences in the distribution of sICH between weekdays and weekends. Also, we found no significant weekday or seasonal variations in in-hospital mortality or functional outcome of sICH. Our results suggest that temporal patterns impact the natural course of sICH in northern Israel. The identification of factors, including biological ones, responsible for seasonal variation in regions with mild seasonal changes requires further research but could aid in the design of strategies for preventing sICH.     

动脉瘤性蛛网膜下腔出血的治疗进展与探讨

颅内动脉瘤破裂导致的自发性蛛网膜下腔出血是一种致残率以及病死率都非常高的一种疾病,其中动脉瘤性蛛网膜下腔出血Hunt-Hess和世界神经外科医师联盟Ⅳ、V级的患者为高分级颅内动脉瘤性蛛网膜下腔出血,这部分患者,无论采取何种治疗方案,预后仍较差。目前对高分级动脉瘤性蛛网膜下腔出血的治疗仍处于探索阶段,并没有形成统一的临床治疗指导规范或临床路径,其中是在采取保守治疗或者手术治疗的问题上存在较大争议,而在选择手术治疗时又存在手术时机的问题,并且随着显微颅内动脉瘤夹闭术的成熟以及颅内动脉瘤的血管内治疗材料和技术的迅速发展及治疗经验的积累,对于患者采取何种手术方式已成为近年来的争议热点,所以如何对这部分患者实施积极有效的治疗而改善其预后,已成为目前神经外科医生必须要解决的焦点问题。     

Hemostatic profile during late pregnancy and early postpartum period in mares

Hemostasis is a physiological process that prevents excessive blood loss and represents a protective mechanism at the time of delivery. Peripartum hemorrhage is a recurring hazardous condition to mare's health; therefore, we aimed to study mares' hemostatic profile to investigate whether physiological adjustments occur during late pregnancy and early postpartum. Fifteen pregnant mares have been monitored from the 34th week of pregnancy until the third week after foaling. Fifteen nonpregnant mares were used as control group. Jugular blood samples were analyzed for platelet count (Plt), prothrombin time (PT), activated partial thromboplastin time (aPTT), and fibrinogen (Fb). Platelet count showed significant changes at foaling (P < 0.05) and a negative correlation (r = −0.968; P = 0.032) with postpartum. Prothrombin time changed (P < 0.05) showing a significant correlation (r = 0.675; P = 0.016) with late pregnancy. Fibrinogen concentrations changed throughout the experimental period (P < 0.0001). The linear regression model revealed a positive correlation (r = 0.9210; P < 0.0001) between Fb and late pregnancy and a negative correlation (r = −0.9583; P = 0.042) between Fb and early postpartum. The shortening in PT recorded in the imminence of parturition along with the increase in Plt and Fb at foaling might reflect a physiological hypercoagulable state that constrains excessive bleeding, enhancing mares' odds of surviving. Our research improves the knowledge about blood coagulation in periparturient mares providing specific information on routine coagulation tests that may support in monitoring mare's hemostatic profile during late pregnancy and early postpartum.     

Inferences of body energy reserves on conception rate of suckled Zebu beef cows subjected to timed artificial insemination followed by natural mating

The influence of body condition score (BCS), rump fat thickness (RFAT), and live weight (LW), and the changes in these parameters during the interval from 165 of prepartum (i.e., 125 days of prior gestation) to 112 postpartum on first service conception and pregnancy rates were investigated in suckled Zebu (Bos indicus) beef cows (n = 266) subjected to timed artificial insemination (TAI) followed by natural mating. The aforementioned parameters were recorded at 165 ± 14 days (mean ± standard error) prepartum (concurrent with the weaning of previous calf), at parturition, and at 42 ± 7 days (at the onset of the synchronization of ovulation protocol), 82 ± 7 days (30 days after TAI), and 112 ± 7 days (60 days after TAI) postpartum. At the start of the breeding season (BS), cows were subjected to a synchronization of ovulation program for TAI. Bulls were placed with cows 10 days after TAI and remained until the end of the study (112 days postpartum). Cows with the highest BCS at parturition had an increased probability of first service conception rate at 60 days after TAI (P = 0.02) and a reduced probability of occurrence of pregnancy loss (P = 0.05). Also, cows had a greater likelihood of conceiving postpartum if they had greater RFAT and BCS at 165 ± 14 days prepartum (P = 0.01 and P = 0.03, respectively) and at parturition (P = 0.0007 and P = 0.003, respectively). Cows that had an increase in RFAT and BCS during the dry period (i.e., interval from weaning of the previous calf to parturition) also had a greater likelihood of conceiving (P = 0.03 and P = 0.06, respectively) during the BS. Among the different time points, RFAT and BCS at parturition had the largest impact on risk of conception during the BS. The LW was a poor predictor of conception during the BS (P = 0.11–0.68) except for LW at 165 ± 14 days prepartum (P = 0.01). Collectively, the findings indicated that the likelihood of conception during the BS was highest in cows that had an improvement in RFAT and BCS during the dry period. Therefore, assuring a good nutritional status in the dry period (BCS ≥ 3.0 at 165 ± 14 days prepartum and ≥3.25 at parturition) is an important aim to optimize the postpartum conception rate of suckled Zebu beef cows subjected to TAI followed by natural mating.     

A finite element analysis of the retinal hemorrhages accompanied by shaken baby syndrome/abusive head trauma

We aimed to elucidate the mechanism of the retinal hemorrhage (RH) accompanied by shaken baby syndrome or abusive head trauma (SBS/AHT) by analyses using a computational model. We focused on a hypothesis that the vitreoretinal traction due to acceleration and deceleration caused by abusive shaking leads to retinal hemorrhage. A finite element (FE) mechanical model with simple spherical geometry was constructed. When the FE mechanical model was virtually shaken, the intensity of the stress applied to the retinal plane agreed well with the results from an analysis using a physical model made of agar gel. Impacts due to falling events induced more intensive tensile stresses, but with shorter duration, than the shake did. By applying a mathematical theory on tackiness, we propose a hypothesis that the time integration of the stress, in the unit of Pa·s, would be a good predictor of the RH accompanied by SBS/AHT. A single cycle of abusive shake amounted to 101 Pa·s of time integration of inflicted stress, while a single impact event amounted to 36 Pa·s. This would explain the paradoxical observation that shaking induces RH while RH due to impact events is only seen in a major event such as a fatal motor vehicle accident.     

鼠药中毒引起消化道出血25例临床诊治分析

目的:城市中杀鼠药中毒容易被临床医师忽视,其引起消化道出血也极易误诊和漏诊,本文分析抗凝血杀鼠药中毒至消化道出血患者的临床表现和诊治方法。方法:回顾性分析2010年1月至2013年8月间我院收治的25例杀鼠药中毒并出现消化道出血病例,对其临床表现和诊治方法进行分析总结,病例均以维生素K1抗凝血方法进行治疗,并比较分析治疗前后患者的凝血酶原时间(PT)、国际正常化比率(INR)、活化部分凝血活酶时间(APTT)、纤维蛋白原(FIB)和出血时间(TT)等出凝血指标进行检测,并进行比较分析。结果:25例因抗凝血杀鼠药物中毒并导致消化道出血患者经维生素K1等抗凝血方法治疗患者全部治愈,消化道出血停止,凝血指标恢复正常,治疗前后患者的凝血指标存在明显差异(P0.05)。结论:抗凝血法对杀鼠药中毒导致消化道出血进行治疗的临床效果显著,值得推广。     

老年蛛网膜下腔出血的治疗方法和预后分析

目的:探讨70岁以上老年蛛网膜下腔出血患者的治疗方法和预后。方法:回顾性分析我院2006-2012年收治的49例老年蛛网膜下腔出血患者的临床资料及其预后。结果:49例患者入院时Hunt-Hess分级:Ⅰ级14例,Ⅱ级8例,Ⅲ级6例,Ⅳ级6例,Ⅴ级15例,其中14例采用开颅动脉瘤夹闭术,10例采用血管内介入栓塞术,25例采用内科保守治疗。治疗后6月,根据ADL量表评价预后(ADL≥60分为预后良好):内科保守治疗者仅3例预后良好,手术及栓塞术者17例预后良好。结论:对于老年蛛网膜下腔出血患者而言,影响患者预后的原因主要是出血导致的脑损伤和症状性脑血管痉挛,通过手术或栓塞术积极治疗破裂动脉瘤是预后良好的重要因素。     

Dynamic Alterations of Cerebral Pial Microcirculation During Experimental Subarachnoid Hemorrhage

The study aimed to investigate the involvement of cerebral microcirculation turbulence after subarachnoid hemorrhage (SAH). Wistar rats were divided into non-SAH and SAH groups. Autologous arterial hemolysate was injected into rat’s cisterna magna to induce SAH. Changes of pial microcirculation within 2 h were observed. It was found that there were no obvious changes of the diameters, flow velocity, and fluid state of microvessels in non-SAH group. With the exception of rare linear-granular flow in A4 arteriole, linear flow was observed in most of the arterioles. There was no blood agglutination in any of the arterioles. After SAH, abnormal cerebral pial microcirculation was found. Spasm of microvessels, decreased blood flow, and agglutination of red blood cells occurred. Five minutes following the induction of SAH, the diameters of the arterioles and venules significantly decreased. The decreased diameters persisted for 2 h after cisternal injection. Decreased flow velocity of venules was found from 5 to 90 min after induction of SAH. Spasm of the basilar artery and increased brain malondialdehyde were also found after SAH. We concluded that cerebral microcirculation turbulence plays an important role in the development of secondary cerebral ischemia following SAH.