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21.
Cheryl M. Mccormick Priscilla Kehoe Sandra Kovacs 《International journal of developmental neuroscience》1998,16(3-4)
Repeated isolation of neonatal rats produces persistent changes in physiology and behavior. In Experiment 1, we examined changes in plasma corticosterone (CORT) levels as a possible mechanism for the effects of isolation. Pups that were isolated from their mother and the nest for 1 h per day on postnatal days (PND) 2–9 were compared to control litters of pups that were either nonhandled or handled but not isolated. On PND 2, compared to nonhandled pups, handled pups had elevated CORT levels that returned to baseline levels within 30 to 60 min of return to the home cage. No significant elevation of CORT levels were found in handled pups on PND 9. The CORT levels of isolated pups were over twice those of nonhandled pups on PND 2 and four times those of nonhandled pups on PND 9. In Experiment 2, we investigated whether the increased CORT release in response to isolation on PND 9 was the result of the pups treatment on the previous six days as against an effect of maturation. Plasma CORT levels were measured in rat pups that were either isolated, handled or nonhandled on PNDs 2–8 during the conditions of isolation, handling and nonhandling on PND 9. There were no differences among the groups in basal plasma levels of CORT. Handling on PND 9 did not result in elevated CORT levels in any of the groups. All three groups showed a significant increase in plasma CORT levels after isolation on PND 9. However, the CORT response to isolation of pups previously isolated on PND 2–8 were significantly higher than pups that were either handled or nonhandled on PNDs 2–8. Thus, daily episodes of isolation potentiate the hypothalamic-pituitary-adrenal response to stress. 相似文献
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救护车担架隔振系统结构参数优化设计 总被引:1,自引:0,他引:1
为了提高救护车担架的乘卧舒适性,根据卧位人体振动响应的特点和汽车悬架系统的振动特性,对救护车担架隔振系统的结构参数进行了优化设计。经过优化设计后的新型担架隔振系统具有更好的减振和隔振效果,其振动加速度均方值明显下降。 相似文献
25.
Yonson Ku Masahiro Tominaga Takeshi Iwasaki Tetsushi Kitagawa Ichiro Maeda Masafumi Shiotani Shinya Kusunoki Yoko Maekawa Masahiro Samizo Takumi Fukumoto Yoshikazu Kuroda Shozo Hirota Yoichi Saitoh 《Surgery today》1996,26(5):305-313
The results of treating 12 consecutive patients with unresectable colorectal hepatic metastases with a hepatic arterial infusion of high-dose Adriamycin, 100–120 mg/m2, using hepatic venous isolation (HVI) and charcoal hemoperfusion (CHP) are reported herein. Adriamycin was administered over 5–15 min under extracorporeal drug elimination by HVI-CHP. HVI was percutaneously accomplished by either the double-balloon technique using a Fogarty occlusion catheter (8/22F) or a balloon-tipped catheter (16F). During the infusion, isolated hepatic venous blood was filtered by CHP and pumped into the left axillary vein. There were no lethal complications, and good hemodynamic tolerance to HVI-CHP was confirmed. Tumor liquefaction accompanied by a sharp decrease in serum carcinoembryonic antigen levels by more than 50% of pretreatment levels was observed in 6 of the 12 patients 1 month after treatment. Apart from chemical hepatitis, which developed in 11 (92%) of the patients, the Adriamycin toxicities were well controlled following the development of nausea and vomiting in 2 patients (17%), leukopenia <2,000/mm3 in 3 (25%), and gastric ulcer in 1 (8%). These results indicate that this method is a safe and useful procedure for otherwise hazardous high-dose intraarterial chemotherapy in patients with unresectable hepatic tumors. 相似文献
26.
APA微胶囊免疫隔离生物膜制备中的质量控制 总被引:3,自引:0,他引:3
为了优化制备条件, 简化工艺, 控制质量, 本文观测了APA(海藻酸盐-聚赖氨酸-海藻酸盐)微胶囊免疫隔离生物膜制备过程中部分物理因素和化学因素与质量的关系.结果表明: 微囊的粒径与静电微囊发生仪脉冲频率呈负相关; 与推进泵速度呈正相关; 与针头内径呈正相关.随着聚赖氨酸浓度的增加, 膜厚度显著增加.微囊的粒径不随聚赖氨酸成膜反应时间延长而改变, 但影响膜的厚度.柠檬酸钠的液化时间对微囊的粒径与厚度均无明显影响.通过优化制备条件, APA微胶囊免疫隔离生物膜将具有更好的通透性、柔韧性、生物相容性和强度. 相似文献
27.
目的 开展有效的麻疹病原学监测,分离麻疹病毒,了解广东省2005-2007年流行的麻疹野病毒分离株基因特征,为控制、消除麻疹提供科学依据.方法 用Veto/Slam细胞从暴发和散发麻疹疑似病例的咽拭子和尿液标本中分离麻疹病毒,并对所有分离到的麻疹病毒通过逆转录-聚合酶链反应(RT-PCR)方法,扩增出核蛋白(N)基因碳末端450个核苷酸片段,对其产物测定基因序列以定型.结果 2005-2007年共收到380份标本,包括咽拭子或尿液标本.共分离到82株麻疹野病毒.2005年病毒分离率为23.58%,2006年病毒分离率为17.11%,2007年病毒分离率为39.13%.病毒分离成功率与病例出疹天数和标本的采集质量有密切关系.结论 我省已经掌握了麻疹病毒的分离和分子生物学鉴定技术,分离率较高;我省多年来流行的麻疹毒株均为H1基因型,与国内流行的优势基因型一致. 相似文献
28.
A new micropore membrane assay for leukocyte migration has been devised. It permits the complete retrieval in monodisperse suspension of functionally intact cells that have traversed the membrane, thus allowing the application of precise, automated techniques, including flow cytometry and electronic particle counting. Hemocytometers may also be used. Direct comparison with 2 different conventional membrane methods showed that the new method performed superiorly. It was also much more economical with regard to time and labor. This technique permitted detection of functional differences between leukocytes isolated from blood in different ways. Data on the duration of concentration gradients in chemotaxis chambers are also presented. 相似文献
29.
Social isolation stress augments angiogenesis induced by colon 26-L5 carcinoma cells in mice 总被引:3,自引:0,他引:3
Wu W Murata J Murakami K Yamaura T Hayashi K Saiki I 《Clinical & experimental metastasis》2000,18(1):1-10
We have previously shown that tumor necrosis factor-α (TNF-α), which is an important angiogenesis-related factor, was over-secreted in male BALB/c mice under social isolation stress as compared with the control, and closely associated with a remarkable elevation of tumor invasion and metastasis of colon 26-L5 carcinoma cells. In the present study, we explored the effect of isolation stress on the angiogenesis caused by colon 26-L5 carcinoma cells in vivo and in vitro. Social isolation lead to the enhancement of tumor growth after intrahepatic implantation with a fragment of colon 26-L5 tumor. Angiogenic response (number of vessels oriented towards tumor mass) and tumor growth (size) were significantly increased in the socially isolated mouse relative to that in the group-housed mice. Furthermore, higher protein level of hepatic TNF-α was found in the stressed mice than that in the control. Expression of mRNA for vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) were also elevated in the tumor regions and liver tissues of the stressed mice in comparison with that in group-housed mice. On the other hand, hepatic sinusoidal endothelial (HSE) cells treated with TNF-α exhibited a marked promotion of the migration, invasion, expression of mRNA for matrix metalloproteinase (MMP)-9, and tube-like formation, but no cytotoxicity against the cells in vitro. The above data suggest that the social isolation stress augmented the tumor-induced angiogenesis probably by up-regulating the angiogenesis-related factors, including TNF-α, VEGF and HGF, and consequently mediating the functions of endothelial cells such as migration, invasion, and tube-like formation. 相似文献
30.
Bruce S. Seal Robert B. Klieforth Anthony E. Castro Werner P. Heuschele 《Methods in Cell Science》1988,11(2):49-55
Summary Cultures of fetal aoudad sheep kidney (FAK), bovine embryonic lung (BEL), and African green monkey kidney (Vero) cells were compared for differential replication of alcelaphine herpesviruses. Cell-free virus appears more rapidly when infected cells are incubated at 33° C rather than at 37° C. Events in the replication and morphologic development of several alcelaphine herpesvirus isolates have been documented using light and electron microscopy. Techniques for indirect immunofluorescence and serum virus neutralization are described. When virus free of host-cell contaminants is desired for biochemical analysis, virus isolates are initially purified on sucrose gradients and then further purified by density gradient centrifugation in Percoll. 相似文献