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排序方式: 共有169条查询结果,搜索用时 31 毫秒
1.
探讨了3种常用的有机磷农药胚胎期暴露对新生鼠脑组织结构的影响。在母鼠妊娠期7.5~11.5 d时,连续5 d每天分别经皮下注射2 mg/kg bw的二嗪磷(diazinon)、2 mg/kg bw的毒死蜱(chlorpyrifos)及50 mg/kg bw乙酰甲胺磷(acephate),显微镜下观察并计数大脑皮层S1区胶质细胞和神经元数量及比率,以及海马CA1、CA3区锥体细胞的数量及体积密度。结果表明,二嗪磷与毒死蜱处理分别使得大脑皮层S1区胶质细胞数减少了14.29%和21.43%;毒死蜱处理导致胶质细胞与神经元比率下降了24.19%;二嗪磷与毒死蜱处理后海马CA1区锥体细胞数量分别下降了9.30%与20.93%,毒死蜱处理后锥体细胞体积密度下降了27.05%;二嗪磷与毒死蜱处理后海马CA3区锥体细胞数量分别下降了22.22%和19.44%,锥体细胞体积密度分别下降了23.54%和18.98%;而乙酰甲胺磷对新生鼠大脑皮层与海马细胞均无明显影响。  相似文献   
2.
For the first time, pre‐ and post‐hepatic plasma lipid profiles were monitored following a single meal in a free‐swimming, non‐anaesthetized fish. Rainbow trout (Oncorhynchus mykiss; 700–1500 g; 10 °C) were equipped with cannulae in the dorsal aorta (DA) and hepatic portal vein (HPV). Simultaneous blood samples, taken from both cannulae at 0, 3, 6, 12, 24 and 48 h postprandial, revealed the time course of the plasma lipid profiles following a single meal (1% of body mass). Primarily monounsaturated fatty acids with the exception of 18:1n ? 9, increased significantly from baseline by 12 h postprandial without greatly affecting total plasma lipid concentrations. Total plasma lipids then showed a small peak at 24 h postprandial, coinciding with a peak in triacylglycerols. We conclude that assimilation of lipids from the digest into the plasma is slower than reported for proteins and carbohydrates in the same species. Furthermore, as there were no significant differences between the HPV and DA, no measurable effect of hepatic passage on plasma lipid levels was resolved. Therefore, we also conclude that, in contrast to that in higher vertebrates, hepatic passage does not seem to have a major role in rainbow trout for modulating the postprandial plasma profile of lipids.  相似文献   
3.
Hippocampal atrophy, which is a component of hippocampal sclerosis and recognized commonly in human intractable epilepsy, is controversial in canine epilepsy. We examined the hippocampal volume in 58 epileptic dogs and 35 control dogs using magnetic resonance (MR) images, and calculated the relative hippocampal volume asymmetry of the right and left hippocampus. Subjectively, there were visible MR imaging abnormalities in seven of the 58 epileptic dogs (12%). The hippocampel volume asymmetric ratio of epileptic dogs (5.84±4.47%) was significantly greater than that of control dogs (1.62±0.88%). Using a cutoff threshold asymmetric ratio of 6% that is indicated in human epilepsy, 28 epileptic dogs (48%) were characterized as having unilateral hippocampus atrophy. The hippocampal volume asymmetry ratio cannot be used to detect bilateral atrophy. In conclusion, although less frequent than that observed in human epilepsy patients, hippocampal atrophy may occur in canine epilepsy.  相似文献   
4.
葛晓鸣  顾伟  徐永健 《核农学报》2019,33(2):322-329
为了探讨大海马蛋白质的高效利用方法,本试验将脱脂大海马粉经碱性蛋白酶和胰蛋白酶联合消解后,酶解液(PH)经超滤膜分离为5组分(PH-Ⅰ、PH-Ⅱ、PH-Ⅲ、PH-Ⅳ、PH-Ⅴ),结合各组分的氨基酸组成,回归分析了各组分的自由基清除能力与氨基酸组成间的相关关系。结果表明,酶解液经超滤膜分离的5组分中PH-Ⅴ(<2 500 Da)抗氧化能力较强,清除DPPH自由基能力为34.2%±0.1%,对超氧阴离子的清除能力为29.2%±0.1%,Fe3+还原力为0.28%±0.1%。海马酶解多肽各组成中疏水性氨基酸含量低于亲水性氨基酸,但疏水性氨基酸对自由基的清除能力起着决定性作用,极性氨基酸和非极性氨基酸可通过协同作用来增强海马多肽清除自由基的能力,且每个单位极性氨基酸的抗氧能力是非极性氨基酸的1.2倍,每个单位芳香族氨基酸的抗氧化能力是脂肪族氨基酸的2倍。本研究不仅制备了一类具有开发价值的抗氧化多肽,并且分析了多肽抗氧化能力与氨基酸组成的相关关系,为大海马的高值化利用提供了理论依据。  相似文献   
5.

Objective

To assess the cardiopulmonary effects caused by reverse Trendelenburg position (RTP) at 5° and 10° in sevoflurane-anesthetized yearling steers.

Study design

Prospective, experimental study.

Animals

Eight Holstein steers aged (mean ± standard deviation) 12 ± 2 months and weighing 145 ± 26 kg.

Methods

In the first phase of the study, the individual minimum alveolar concentration (MAC) of sevoflurane was determined using electrical stimulation. In the second phase, the effects of RTP were assessed. The animals were anesthetized on three separate events separated by ≥7 days in an incomplete crossover design: control treatment using a table without tilt (RTP0); treatment with the table at 5° RTP (RTP5) and table tilted 10° RTP (RTP10). Subjects were physically restrained in dorsal recumbency on the table, which was already tilted according to each treatment. Anesthesia was induced with sevoflurane at 8% in 5 L minute–1 oxygen via face mask followed by maintenance with sevoflurane at 1.3 MAC and spontaneous breathing. Cardiopulmonary variables were obtained immediately after instrumentation (T0) and then after 30, 60, 120 and 180 minutes (T30, T60, T120 and T180, respectively).

Results

The mean sevoflurane MAC for the eight steers was 2.12 ± 0.31%. Cardiac output was lower at all time points and the systemic vascular resistance index was higher at T120 and T180 in RTP10 compared with RTP0. Oxygen consumption was lower at T0 and at T180 in RTP10 compared with RTP0 and at all time points except T30 compared with RTP5. Oxygen extraction was lower at T0 in RTP10 compared with RTP0 and RTP5, and at T60 and T180 compared with RTP5.

Conclusions and clinical relevance

RTP 5° and 10° did not improve ventilatory and oxygenation variables in sevoflurane-anesthetized steers when compared with no tilt, however the cardiovascular variables were adversely affected in RTP10.  相似文献   
6.
目的 研究复方柴金解郁片对慢性应激抑郁模型大鼠HPA轴及海马单胺神经递质的影响,探讨其可能的抗抑郁机制。方法 将SD大鼠随机分为6组:对照组、模型组、氟西汀组(5.4 mg/kg)、复方柴金解郁片高、中、低剂量组(2.74、1.37、0.68 g/kg),采用慢性不可预见性温和应激建立抑郁模型,于造模同时给药,连续28 d。采用蔗糖偏好实验和旷场测试检测大鼠的抑郁样行为,Morris水迷宫检测大鼠的学习记忆能力,HE染色观察大鼠海马病理结果变化,ELISA法检测大鼠血浆促肾上腺皮质激素释放激素(CRH)、促肾上腺皮质激素(ACTH)、皮质酮(CORT),以及海马5-羟色胺(5-HT)、5-羟吲哚乙酸(5-HIAA)、去甲肾上腺素(NA)、多巴胺(DA)的含量。结果 与抑郁模型组比较,复方柴金解郁片组大鼠蔗糖偏嗜度及活动次数均显著提高,学习记忆能力提升,海马病理损伤情况得到缓解,血浆CRH、ACTH、CORT含量下降,海马组织内5-HT、NA、DA含量上升,5-HIAA含量下降(P<0.05)。结论 复方柴金解郁片能显著改善模型大鼠情绪和学习记忆功能、缓解海马组织损伤,其作用可能与抑制HPA轴亢进、增加脑内单胺递质含量有关。  相似文献   
7.
为探讨原代Wistar大鼠海马神经细胞的体外培养方法,本研究取新生24 h内的Wistar大鼠海马组织,无菌剪碎后采用胰酶消化法分离细胞,用含20%胎牛血清的DMEM/F12培养基培养,逐日在倒置相差显微镜下观察。结果发现,从海马组织中分离出的神经细胞具有增殖能力,细胞对数生长期为2~8 d,最长培养30 d;细胞经免疫荧光鉴定Nestin表达呈阳性;免疫组织化学结果显示,在传代培养细胞的胞体和突起均有NF阳性标记物,GFAP抗体和CD68抗体显色均为阴性。由此可见,分离培养的细胞是具有自我更新增殖和多分化潜能的神经元细胞。  相似文献   
8.
细锯脂鲤背鳍和脂鳍的发育观察和转录组比较分析   总被引:1,自引:1,他引:0  
观察了细锯脂鲤脂鳍和背鳍形态和骨骼发育,在此基础上比较了脂鳍、背鳍原基和背鳍共3个组织的转录组,发现细锯脂鲤背鳍原基28 DAH(Day After Hatch,DAH)出现,30 DAH仔鱼背鳍鳍条已出现分化,35 DAH背鳍鳍条已硬骨化,脂鳍在32 DAH开始出现。背鳍原基、背鳍和脂鳍这3个组织共同表达基因有14 115条,分别占背鳍原基转录组的84.01%、背鳍的83.19%、脂鳍的84.14%,提示脂鳍发育的主要调控机制与背鳍发育较为相似。相同基因表达水平差异方面,相比脂鳍,背鳍原基和背鳍之间的基因表达模式要更为相似。发现有些与鳍发育相关的基因在背鳍和脂鳍转录组中存在差异。这些研究结果为进一步深入了解脂鳍发育奠定了基础。  相似文献   
9.
为探讨胚胎晚期暴露细菌脂多糖(LPS)的中年CD-1小鼠背侧海马的类泛素化蛋白(SUMO-3)含量有无年龄相关性改变。采用免疫组织化学技术检测LPS暴露组和对照组CD-1小鼠背侧海马DG区、CA1区和CA3区各亚层的SUMO-3表达。结果表明,两组间各区各亚层的SUMO-3含量无明显差异。  相似文献   
10.
为研究鲤疱疹病毒Ⅱ型(Cy HV-2)体外感染复制特征以及异育银鲫抗病毒免疫应答反应。本实验采用组织块培养法建立了异育银鲫背鳍细胞的原代培养体系。结果显示,在10 d左右可观察到组织块迁移分离出新的单层细胞,3周左右细胞可覆盖底部面积为25cm2培养瓶的底部;经Cy HV-2悬液感染离体培养的原代细胞,3 d后病毒滴度增殖至106拷贝/m L;在病毒感染6 d后出现典型的细胞病变效应;Cy HV-2感染原代细胞后,分析前期通过鱼体水平实验鉴定出的与该病毒感染相关的免疫基因:PNP5a、MPO、MHCⅠ、LYZ-C、IL-11、ITLN、PNP5a和DUSP,Real-time Rt-PCR结果显示大部分基因在细胞水平均有显著性的上调,与鱼体水平实验结果一致。本研究建立了原代培养的异育银鲫背鳍细胞,用于构建体外感染Cy HV-2病毒的细胞模型,为深入研究Cy HV-2的感染复制规律及其与宿主的相互作用关系,以及细胞水平筛选抗病毒药物实验奠定了基础。  相似文献   
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