静脉注射多巴胺对休克动物肾微循环血液灌流量的影响(激光多普勒血流计测定结果)

用激光多普勒微循环血流计研究了多巴胺对失血性休克大鼠(n=44)肾微循环血液灌流量的影响,结果发现20μg及40μg/0.1ml/100g体重静脉注射后5分钟,20分钟时肾灌流量均有明显增加,月龄低的大鼠比月龄高的大鼠反应更敏感。失血性休克家兔(n=17)静脉注射多巴胺后(100μg/1ml/kg体重)20分钟,肾皮质微循环血液灌流量明显增加,但是用电磁血流量计同步测定左肾动脉血流量,结果发现并无明显增加。根据上述结果,作者认为多巴胺增加肾皮质微循环血液灌流量的作用并不是通过肾血流量的增加,而可能是通过肾微循环内血液再分布实现的。     

蝮蛇抗栓酶对失血性休克动物肾微循环血液灌流量的影响

在40只失血性休克大鼠中静脉注射不同剂量的蝮蛇抗栓酶(0.05U,0.025U/100g B.W.)后用激光多普勒微循环血流量计测定肝、脾、肾、小肠及尾部微循环血流量,结果发现肾微循环血流量在用药后5～20分均有显著增加(P<0.05),在15只家兔的类似实验中同时测定肾表面微循环血流量与肾动脉血流量(电磁血流量计),结果发现静脉注射蝮蛇抗栓酶后(0.05U/ml/kg),肾动脉血流量并无明显增加,而肾皮质微循环血液灌流量显著增加,并与尿量增加一致。作者认为蝮蛇抗栓酶具有降低肾微循环血流阻力,加快流速,增加肾皮质微循环血液灌流量的作用。     

灵芝护肤霜对皮肤微循环血液灌流量和含水量影响的初步观察

本文观察了用含有中药灵芝成分的护肤霜（油）及不含灵芝的对照霜（油），局部涂擦豚鼠腹部皮肤一个月前后局部皮肤微循环血液灌流量和含水量的变化。结果表明，涂灵芝护肤霜或油15天和30天时局部微循环血液灌流量有增加趋势，但统计学上无显著差异（P＞0．05），涂灵芝护肤霜30天局局部皮肤含水量明显升高（P＜0．05），但涂灵芝护肤油变化不显（P＞0．05），说明灵芝护肤霜具有较好的保留皮肤水分的作用。     

失血性休克时血液流变性异常的研究进展

手术意外、严重创伤以及交通事故等均可引起急性失血，最终导致失血性休克（Hemorrhagic Shock，HS），严重威胁着人类健康。随着休克微循环学说及休1克细胞、分子机制的逐步阐明，临床上对于HS的救治取得了很大进展。由于在休克及救治过程中出现血液流变性异常，如血粘度改变，加重组织灌流不足、凝血功能紊乱以及血管低反应性、顽固性低血压等，进一步加剧微循环障碍和组织缺血缺氧，尤其是肠道缺血可导致肠道屏障功能降低，     

一氧化氮在大鼠创伤局部微循环灌流减少中的作用

目的和方法：用激光多普勒微循环血流仪测定大鼠断肢局部微循环血液灌流量，用比色法测定血浆亚硝酸盐（ＮＯ２－）水平间接反映血浆一氧化氮（ＮＯ）含量。结果：（１）断肢局部微循环血液灌流量在断肢Ｏ、１、２和３ｈ均明显下降，局部股静脉血浆ＮＯ２－含量在断肢２、３ｈ显著降低，断肢２、３ｈ局部股静脉血浆ＮＯ２－水平与局部微循环血液灌流量呈显著正相关。（２）ＮＯ合成底物左旋精氨酸（Ｌ－Ａｒｇ）能改善断肢２、３ｈ的局部微循环血液灌流量，一氧化氮合成抑制剂左旋单甲基精氨酸（Ｌ－ＮＭＡ），可抑制此作用。（３）断肢３ｈ局部股静脉血浆ＮＯ２－水平Ｌ－Ａｒｇ组明显高于生理盐水（ＮＳ）组（Ｐ＜００５），Ｌ－Ａｒｇ合用Ｌ－ＮＭＡ组则明显低于ＮＳ组（Ｐ＜００５）。结论：断肢创伤通过内源性Ｌ－Ａｒｇ－ＮＯ通路而降低ＮＯ生成，参与断肢局部２、３ｈ的血管痉挛和微循环血液灌流量下降     

缺血再灌注家兔微循环、血液流变性的变化及银杏叶提取物的干预作用

目的：研究缺血再灌注对微循环、血液流变性的影响及银杏叶提取物的干预作用。方法：复制家兔缺血再灌注模型。采用显微电视和微机图像处理系统对家兔球结膜微循环进行定量分析。结果：用药组在缺血30min、再灌注30min等时相，与对照组比较，其微动／静脉口径（3、4级）、微静脉流速／流量、毛细血管条数均增加（P＜0．05），红细胞聚集、白色微小血栓等均减少（P<0．05）。结论：家兔缺血再灌注存在明显微循环障碍，银杏叶提取物有保护微循环的作用。其机制可能与扩血管、改善血液流变学有关。     

~(86)Rb摄取示踪法评定几种中草药提取物对心、肾组织微循环灌流量的影响

以８６铷（８６Ｒｂ）摄取示踪法检测评定了缬草、红藤、姜黄三种中草药的七种不同的提取物对健康清醒小鼠及垂体后叶素—蔗糖静脉注射所致心肌缺血大鼠的心、肾组织微循环灌流量的影响。结果显示：缬草挥发油、缬草环烯醚萜可以显著增加健康小鼠心、肾微循环灌流量，改善心肌缺血；姜黄与红藤提取物也可增加心肌微循环灌流量；药典规范的缬草浸膏对心、肾微循环灌流量则无明显影响     

实验性高胆固醇血症家兔血液流变性改变在微循环障碍中的作用

本文利用实验性高胆固醇血症家兔模型,研究了微循环灌流和血液流变性改变间关系。结果表明,微循环流量、流态、流速,微血管形态有明显改变,而这些变化与血清中胆固醇浓度,血浆粘度,全血粘度,红细胞聚集性及红细胞变形有着明显相关性。血液流变性变化构成此模型微循环障碍的基础。     

高脂血症大鼠血液流变学及肝脏微循环的改变

目的 探讨高脂血症大鼠血液流变学及肝脏微循环的改变。方法 Wistar大鼠随机分为（1）正常组：喂普通饲料；（2）高脂血症组：喂高脂饲料4周，每组6只。于造模4周后测定血清血脂水平、体质量及肝质量与体质量之比、血液流变学和肝脏活体微循环的改变。结果 喂高脂饲料4周后肝脏体积增大，体质量及肝质量明显高于正常对照组（P〈0．01）。肝组织标本显示肝细胞肿胀、脂肪性变，肝细胞的胞浆内充满大小不等的脂滴。血清胆固醇、低密度脂蛋白较正常对照组明显增高（P〈0．01），高密度脂蛋白减少，甘油三脂变化不大；血压及血浆黏度较正常组增高明显（P〈0．05）；肝脏活体微循环观察显示肝脏微血管数明显减少，肝细胞索增大，泡沫状突起压迫周围血管，血流速度减慢，血管内有红细胞聚集和白细胞黏附。结论 短期内高脂食物的摄入可造成脂质代谢紊乱，继而发生血液流变学及肝脏微循环障碍。     

激光多普勒血流量图像仪在微循环基础与临床研究中的初步应用

利用激光多普勒效应非接触式扫描成像的原理，我们用激光多普勒血流量图像仪（ＬＤＩ）测量失血和再灌注期间大鼠小肠组织灌流量的变化；比较人体皮肤鲜红斑痣在激光治疗前后血流量的变化以及心脏直视手术中心脏在不同状态下心肌灌流量的改变。实验结果表明ＬＤＩ能够客观反映在不同的功能状态下组织血液灌流量的变比。提示：测量一区域组织表面血流量可反映组织微循环功能，在临床检查中具有重要意义；而作为自动化测量系统，激光多普勒血流量图像仪的性能优于激光多普勒血流量计。     

Co-ordination of cough and swallow in vivo and in silico

Coughing and swallowing are airway-protective behaviours. The pharyngeal phase of swallowing prevents aspiration of oral material (saliva, food and liquid) by epiglottal movement, laryngeal adduction and clearing of the mouth and pharynx. Coughing is an aspiration-response behaviour that removes material from the airway. Co-ordination of these behaviours is vital to protect the airway from further aspiration-promoting events, such as a swallowing during the inspiratory phase of coughing. The operational characteristics, primary strategies and peripheral inputs that co-ordinate coughing and swallowing are unknown. This lack of knowledge impedes understanding and treatment of deficits in airway protection, such as the co-occurrence of dystussia and dysphagia common in Parkinson's and Alzheimer's diseases, as well as stroke.     

Incorporation and Disappearance of Sulfate in Different Regions of Mouse and Rat Costal Cartilage in vivo and in vitro

A rapid and simple method for liquid scintillation counting of ³³S-sulfate in biological tissues is described. Sulfate incorporation per mg dry weight into selected lateral, medial and intermediate regions of ribs was studied using costal cartilage from rats and mice. In vitro, cartilage pieces embracing the osteochondral junction had 2–4 times larger incorporation rate than the remaining homogeneous parts of the ribs, both if entire rib cages or stripped and diced cartilage were incubated. After in vivo injection to rats and mice the incorporation rates of sulfate into the region of the osteochondral junction was 2.6 times that found in “resting” cartilage in rats and 4.4 times in mice. The ³⁵S-sulfate uptake in the ribs per mg dry cartilage diminished in the caudal direction. Growth of the chest cage was mainly a longitudinal growth of the bony segments. Marked differences in the disappearance rates of previously incorporated sulfate were found in different regions along the rib. Rapid sulfate disappearance was found in the bony segment which, however, had incorporated only one seventh of the amount per mg taken up by “resting” cartilage. The “resting” cartilage segments exhibited a steady slow disappearance rate for sulfate and the osteochondral junction region consisting of several differently active tissues showed a rapid sulfate disappearance in the beginning followed by a slow clearance after 2 weeks similar to that of “resting” cartilage. The necessity of careful selection of costal cartilage samples with respect to regional differences is emphasized.     

Evaluation of the genotoxic and embryotoxic potential of chlorpyrifos and its metabolites in vivo and in vitro

The genotoxicity and embryotoxicity of chlorpyrifos (CPF) and two metabolites were evaluated using the chick embryo, Chinese hamster ovary cells, and by examining blastocysts from superovulated cows crossed to chlorpyrifos-treated bulls. Chlorpyrifos and metabolites were dissolved in acetone and administered to 3-day embryos by the air cell method. The LD50 was 1,500 micrograms/embryo when mortality was checked through and including 17 days of development. The metabolites were more embryotoxic than the parent compound, CPF. Chlorpyrifos and metabolites did not increase the sister chromatid exchange (SCE) frequency above background at any dosage in the 3-day chick embryo assay. Similarly, none of these compounds increased SCE frequencies in three-point dosage tests (1, 10, 100 micrograms/ml) using Chinese hamster ovary cells. Controls in these assays consisted of the solvent carrier acetone (7.0 +/- 2.5 SCE/cell) and 8.6 micrograms/ml methyl methane sulfonate (30.5 +/- 7.4 SCE/cell). Studies of bovine blastocysts obtained from superovulated cows crossed with Dursban 44 treated bulls did not reveal evidence of chromosome aberrations or developmental anomalies associated with pesticide application. However, reproductive performance of breeders may be subnormal as a result of severe poisoning. This underscores the limitations of short-term assays and emphasizes the need to perform thorough toxicological assays of a chemical according to actual usage patterns in the species of concern.