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61.
血脑屏障是隔离外周体循环和中枢神经系统的屏障结构.它可以选择性允许血液中的一些物质通过脑微血管内皮细胞进入大脑中.除了脑微血管内皮细胞之外,血脑屏障的组成主要还有星型胶质细胞、周细胞、神经元和细胞外基质.本试验通过原代培养猪脑微血管内皮细胞和星型胶质细胞,以Transwell细胞板为载体构建猪体外血脑屏障的共培养模型.经过4h渗漏试验和TEER电阻的测定试验显示所构建的猪体外血脑屏障的模型具备了血脑屏障基本的生物学特性,可以用于猪血脑屏障相关疾病尤其是人兽共患性疾病致病机制的研究. 相似文献
62.
Evaluation of a new oscillometric blood pressure monitor in isoflurane-anesthetized dogs 总被引:2,自引:1,他引:2
Objective This study was conducted to evaluate the performance of a new veterinary oscillometric noninvasive blood pressure (NIBP) monitor in anesthetized dogs. Study design Assessment was made to determine how closely indirect measurements were associated with direct measurements, and if there were statistically significant differences between the measurements by site. Animals Six mongrel dogs weighing 27.8 ± 2.9 kg. Methods Dogs were anesthetized with thiopental and maintained with isoflurane, which was delivered with controlled ventilation. Direct pressure measurements were obtained via a percutaneously placed arterial catheter. A range of systolic arterial pressures (SAP) were achieved by changing the isoflurane concentrations. Sites of cuff placement for indirect measurements were identified as metacarpus, metatarsus, and anterior tibial. Results At pressures below 80 mm Hg, indirect systolic measurements averaged 4 ± 3 mm Hg, higher than the direct values. At normal and high levels, indirect systolic measurements underestimated direct values by 18 ± 6 and 23 ± 6 mm Hg, respectively. Diastolic and mean pressure measurements followed the same trend, with indirect values being lower than the direct arterial pressures. Systolic, diastolic and mean arterial pressure measurements differed by cuff‐placement site. Conclusions When analyzed by site and level, indirect systolic and mean arterial blood pressures during hypotension were essentially the same as direct pressures. However, at pressures within the normal or high range, indirect measurements underestimated the direct pressures. Clinical relevance Noninvasive blood pressure measurements with a new oscillometric monitor provided an excellent means of detecting arterial hypotension in anesthetized dogs. The metatarsal site for cuff placement was slightly better than the metacarpal or anterior tibial site, considering that the regression line was closest to complete equality between the indirect and direct measurements for SAP. 相似文献
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双峰驼水代谢与血液中无机离子浓度的动态关系 总被引:5,自引:1,他引:5
对双峰驼禁水15d,于禁水前、后及暴饮后采血,测定其血液中多种无机离子的浓度变化。结果表明,全血碳酸氢盐含量在禁水期变化极显著,与禁水前相比,冬季试验升高28.09%,夏季试验升高26.59%;暴饮后快速下降,冬、夏季试验分别比禁水前低9.5%和7.8%,4d后恢复正常。血清中K+和Fe2+含量未见统计学差异。血清中Na+、Cl-、Ca2+、Mg2+、和P3+的含量于禁水期逐渐上升,暴饮后快速下降,其变化均有显著差异,其中Na+的正常值显著高于其他反刍动物。结果表明,双峰驼在禁水期具有较高的血液渗透压和碱储量,其对保证缺水时血液酸碱平衡的调节,维持血容量,保证机体正常水代谢功能具有重要作用,是骆驼耐干渴的重要原因之一。 相似文献
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66.
B. Serrano S. Almería I. García-Ispierto J.L. Yániz A. Abdelfattah-Hassan F. López-Gatius 《Research in veterinary science》2011,90(3):457-462
Pregnancy is characterized by transient changes in the maternal immune system, also evident at peripheral level. The present study analyzes the kinetics and possible factors affecting peripheral white blood cell populations throughout pregnancy in a herd of high-producing dairy cows chronically infected or not with Neospora caninum. We examined 54 pregnant parous cows: 29 Neospora-seronegative and 25 Neospora-seropositive cows. Blood samples were collected on Days 90, 120, 150, 180 and 210 of gestation. General Linear Model (GLM) repeated measures analysis of variance showed that the interaction Neospora-seropositivity × parity significantly affected total leukocyte, neutrophil and monocyte counts with lower levels of total leukocytes, lower neutrophil and higher monocyte counts recorded in primiparous Neospora-seropositive cows. In addition, N. caninum-seropositive cows had significantly increased monocyte counts on Day 180 of gestation compared to seronegative ones. Other factors significantly associated with changes in total and/or differential leukocyte profiles were period of pregnancy, season, twin pregnancy and milk production. In conclusion, a parity-associated effect of chronic N. caninum infection was observed on peripheral blood cell profiles in dairy cattle during gestation. 相似文献
67.
Lin CM Jeng CR Chang HW Guo IC Huang YL Tsai YC Chia MY Pang VF 《Veterinary immunology and immunopathology》2008,124(3-4):355-366
Information regarding the susceptibility of swine lymphocytes to PCV2 is rather limited. To further explore and characterize the PCV2 infection in swine lymphocytes, an in vitro model using concanavalin A (Con A)-stimulated peripheral blood lymphocytes (PBLs) obtained from clinically healthy PCV2-carrier pigs was introduced. It was found that the PCV2 antigen-containing rate was below 2% in PBLs from healthy PCV2-free pigs following treated simultaneously with Con A and PCV2. However, significantly higher PCV2 antigen- and nucleic acid-containing rates could be seen in Con A-stimulated PBLs from clinically healthy PCV2-carrier pigs. Prior to Con A treatment, both of the PCV2 antigen- and nucleic acid-containing rates in PBLs from healthy PCV2-carrier pigs were less than 1%; however, they reached 22.1+/-5.7% by flow cytometry and 27.1+/-6.5% by in situ hybridization, respectively, at 4-day post-incubation with Con A. Phenotyping of PCV2 antigen-containing cells revealed that PCV2-positive cells could be detected in both T and B lymphocyte populations within which IgM-positive B lymphocytes appeared to have a relatively higher positive rate. The Con A-stimulated PBLs also displayed a significantly higher viral load by the measurement of either PCV2 DNA copy number or viral titer when compared with the non-treated PBLs from healthy PCV2-carrier pigs. The results indicate that PBLs, especially IgM-bearing B lymphocytes, are indeed susceptible to PCV2 infection and PCV2 is capable of replicating in dividing lymphocytes. This activation-induced replication may explain in part the pathogenesis of lymphoid depletion in PMWS-affected pigs. 相似文献
68.
伊犁马1000m速步训练赛各阶段静脉血中血气指标变化研究 总被引:1,自引:0,他引:1
利用i-STAT血气分析仪检测12匹伊犁马1000 m速步训练赛静息、热身后及赛后即刻、15 min、30 min、60 min时静脉血中的血气指标,并对各血气指标的差异性和相关性进行统计分析。结果表明,运动前后静脉血中PvCO2、PvO2、HCO3、TCO2、SvO2和Glu变化差异不显著(P>0.05)。血液pH、BE和Ca2+在赛后即刻均明显降低,但经15 min休息后都基本回升到静息水平;K+、Hct和Hb在赛后即刻均显著增加(P<0.05),但经15 min休息后都基本回降到静息水平。血液pH与BE、HCO3呈极显著正相关(P<0.01),与TCO2浓度呈显著正相关(P<0.05),Hct、Hb与pH和HCO3呈极显著负相关(P<0.01),与K+呈极显著正相关(P<0.01)。因此,BE、HCO3、TCO2、Hct和Hb对酸碱平衡均有一定的调节作用;Na+、K+和Ca2+对机体运动具有一定的调节作用。 相似文献
69.
为了评价抗感败毒口服液临床用药的安全性,对SD大鼠的生长和血液理化指标进行了试验研究,选用了健康大鼠80只,雌雄各半,随机分为高、中、低剂量组和对照组,其中高剂量组、中剂量组和低剂量组分别灌胃给予该口服液8 mL/kg、4 mL/kg和2 mL/kg体重,对照组按8 mL/kg体重灌服生理盐水,每天一次,连续给药35 d。各组末次给药24 h后,检测大鼠体重、血常规指标、血液生化指标、脏器系数及组织病理变化情况。结果表明,抗感败毒口服液各剂量组大鼠的体重、血液学检查、血液生化指标检查与对照组比较,均无显著差异(P>0.05),雌性大鼠高剂量组的肝脏脏器指数与对照组相比有显著差异(P<0.05),其他无显著差异(P>0.05)。肉眼观察实质器官无异常病变。结果提示,长期应用抗感败毒口服液对大鼠生长和血液理化指标无显著影响,临床用药安全。 相似文献
70.