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31.
Objective To study the effects of prenatal and postnatal perfluorooetane sulfonate (PFOS) exposure on spatial learning and memory, N-methyl-D-aspartate receptor 2B (NR2B) mRNA and protein level in frontal cortex and hippoeampus of rat pups and to explore the mechanism of developmental neurotoxicity induced by PFOS. Methods Twenty-eight pregnant mrs were randomly divided into three groups in proportion of 3: 2: 2,including control group (C), low dose group (L) and high dose group (H) by means of randomized number table, which respectively received 0,7.2, 14.4 mg/kg PFOS feed from pregnancy day 0 to postnatal day(PND)30 by free feedings. The animal models of prenatal and postnatal non-exposure (CC), prenatal exposure (LC and HC), postnatal exposure (CL and CH), and prenatal and postnatal exposure (LL and HH) to PFOS were established by cross-fostering method. The spatial learning and memory were measured by water maze experiment,the NR2B mRNA levels in frontal cortex of rat pups was determined with semi-quantitative RT-PCR, NR2B protein express in cerebral cortex (frontal and tempera]cortex) and hippocampus (CAI, CA3, CA4 and DG regions) of rat pups was detected by immunohistochemistry. Results The escape latency of CL, CH, LL and HH groups pups in water maze experiment were (99. 83±25.77) s, (111.30±17. 82) s, (106. 40±18. 71) s, (107.70±16. 85) s, and longer as compared with CC group[(54.90±26.69)s](q value were 4.349,4.773,6.026 and 5.641, respectively,P<0. 01). The number of errors of HH group rat pups entering dead end was (22. 30±7.56) at the training day 4,and it was significantly higher than that of CC group (9. 80±4. 64) (q=5. 173,P<0. 01). The NR2B mRNA levels of frontal cortex of pups in HC group at PND1 ,and LC group, HC group and HH group at PND14 were (0. 167±0. 008), (0. 364±0. 035), (0. 341±0. 030) and (0. 328±0. 045) respectively,which were significantly lower than CC group (0.271±0.060) and (0.465±0.067) (q values were 3. 547, 3. 739, 4. 597 and 5. 006, respectively, P<0.05) . The results of immunohistochemistry indicated that NR2B protein express of the hippocampus CA1 region of pups in LC group was (0.091±0.005),and showed significant lower than CC group which was (0. 123±0.009) at PND1 (q=5. 209 ,P<0. 05). At PND14, the effect of PFOS extended to cerebral cortex and hippocampus regions. At PND28, the effects of PFOS were showed in hippocampus CA1, CA3 and temporal cortex regions. Conclusion Prenatal and postnatal exposure to PFOS should result in the spatial learning and memory damage,and the mechanism might be possibly involved in the decrease of NR2B level in cerebra lcortex and hippocampal formation regions. 相似文献
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33.
幼儿腹膜后神经母细胞瘤较为少见,本院近期收治1例,现报告如下。患儿,男,3岁,因"无明显诱因反复腹胀10余天"入院。起病以来腹部膨隆,有增大倾向,无畏寒、发热,无恶心、呕吐、腹泻等症状。当地医院CT检查提示:左肾前方(相当于T12至S1水平)见一巨大软组织肿块,大小约12cm×9cm,共9个层面可 相似文献
34.
全氟辛烷磺酸对大鼠兴奋性氨基酸影响 总被引:2,自引:2,他引:2
目的探讨全氟辛烷磺酸(PFOS)与大鼠中枢神经系统兴奋性氨基酸的时间反应关系。方法将成年Wistar大鼠随机分为1个对照组和4个实验组[25mg/(kg·bw),染毒后2,4,8,24h];用PFOS对成年Wistar大鼠经口1次染毒;对照组给予等体积的2%吐温-80溶液。高效液相色谱法(HPLC)测定脑组织中谷氨酸、天冬氨酸、γ-氨基丁酸及甘氨酸含量变化。结果谷氨酸2,4,8h含量分别为(0.89±0.162),(0.75±0.276),(0.84±0.542)μmol/(g·protein),与对照组(1.30±0.063)μmol/(g·protein)比较,差异有统计学意义(P〈0.05)。天冬氨酸无显著变化。甘氨酸8,24h含量分别为(1.24±0.352),(1.09±0.215)μmol/(g·protein),与对照组(1.54±0.120)μmol/(g·protein)比较,差异有统计学意义(P〈0.05)。γ-氨基丁酸含量24h为(1.68±0.188)μmol/(g·protein),与对照组(2.03±0.370)μmol/(g·protein)比较,差异有统计学意义(P〈0.05)。结论低剂量PFOS染毒后中枢神经系统出现先抑制后兴奋的症状可能与兴奋性氨基酸的参与有关。 相似文献
35.
沈阳市社区老年人健康状况及卫生服务需求调查 总被引:1,自引:0,他引:1
目的了解沈阳市社区老年人的健康状况及卫生服务需求。方法对505名60岁以上的老年人进行问卷调查,包括老年人的生活与居住情况,日常生活活动能力,慢性病患病情况,卫生服务需求等。结果被调查者中日常生活活动能力下降者为10.9%,功能明显障碍者为14.5%;慢性病的患病率为75.2%;有54.2%的老年人需要1项或1项以上的社区卫生服务项目,其中定期体检占36.1%,健康教育为25.3%。结论针对该社区老年人的健康状况,加强社区健康教育、医疗、预防、保健是做好社区老年卫生服务的重要措施。 相似文献
36.
肠外瘘是胃肠道术后的严重并发症,高流量肠外瘘…合并切口裂开时如何有效地控制和收集流出的肠液,使切口和周围皮肤不受污染和刺激,这是临床上处理肠外瘘的难题。对于此类患者,普遍采用的措施是开放式滴水双套管负压吸。然而,此方法存在较多问题,结果不尽人意。作者自2002年4月至2006年8月对44例合并伤口裂开的高流量肠外瘘患者采用粘贴式负压冲吸器治疗,与1996年2月至2002年3月治疗的38例同类患者在相比。在治愈率、伤口换药次数、敷料消耗量、伤口愈合时间、[第一段] 相似文献
37.
深静脉穿刺置管术是抢救重危病人、中心静脉压测定、长期静脉给药、胃肠道外营养支持治疗、化疗病人等常用的外科技术,在普通外科应用广泛。我科对胃肠道手术患者或危重患者常规行深静脉穿刺置管术。由于锁骨下静脉较颈内静脉易于固定,检测中心静脉压较颈内静脉标准、可靠,故首选锁骨下静脉穿刺途径。1年来共完成800例锁骨下静脉穿刺置管术,现总结如下: 相似文献
38.
1996年至2005年,我院共收治急性胰腺炎322例,其中符合重症急性胰腺炎(sAP)诊断标准89例(37.6%)。本文仅就重症急性胰腺炎的治疗问题进行总结和讨论。[第一段] 相似文献
39.
原发性甲状腺恶性淋巴肉瘤(PMLT)是起源于甲状腺内淋巴细胞的恶性肿瘤,又称甲状腺恶性淋巴瘤,临床少见,术前常易误诊为甲状腺炎、结节性甲状腺肿、甲状腺癌等疾病。回顾我院近10年来收治的甲状腺恶性肿瘤251例发现有5例PMLT,现分析如下。1 资料和方法1.1 临床资料 我院自1989年12月至1999年2月,共收治甲状腺恶性肿瘤251例,其中5例为甲状腺恶性淋巴瘤,男1例,女4例。年龄38~69岁,平均57岁。病史2周至2年7个月。病变累及双侧2例,均为弥漫性,质地较硬,其中1例伴有颈部活动受限… 相似文献
40.
Objective To investigate the effects of tissue specific cytosine deaminase/5-fluorocytosine (CD/5-FC) thermotherapy on hepatic metastasis of colonic carcinoma in nude mice. Methods Forty-five nude mice were randomly divided into control group, 5-FC group and 5-FC thermotherapy group according to the random number table (15 mice in each group). Mice models of hepatic metastasis of colonic carcinoma were established by portal vein injection of LoVo/CEACD cells. The hepatic metastasis rate and number of metastatic nodules of the 3 groups were compared by ehi-square test and one-way ANOVA. The pathological changes in tumor tissues and apoptotic index of tumor cells were observed. The expression of the CD gene in tumor tissues was detected by fluorescent quantitative RT-PCR and Western blot. Results The number of metastatic nodules and liver metas-tasis rate were 4.6±1.3 and 100.0% in control group, 2.2±1.0 and 60.0% in 5-FC group, 0.5±0.8 and 13.3% in 5-FC thermotherapy group, with statistical difference among the 3 groups (F=25.898, χ2=5.208, 19.548, 5.168, P<0.05). The mean apoptotic indexes of tumor cells of the 3 groups were 4.6%, 9.9% and 17.4%, respectively. Vacuolar degeneration, cell necrosis, cytolysis and apoptotic bodies were mostly observed in the 5-FC thermotherapy group. The expression of CD gene in tumor tissue was detected in all the groups. Conclusion Tissue specific CD/5-FC thermotherapy has inhibitory effects on the hepatic metastasis of LoVo cells transfected with CD gene. 相似文献