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81.
目的探讨急性高原缺氧条件下氰化钠中毒对大鼠脑组织能量代谢的影响。方法雄性sD大鼠,分为平原组和高原组。平原组动物在本地常规实验室内处理。高原组动物放置于模拟4000m海拔高度的低压舱内3d后开始实验。为大鼠腹腔注射氰化钠(NaCN)3.6mg/kg染毒,于0、0.5、1、2、4、6h6个时相点麻醉后断头取脑。以干湿质量法测定脑组织含水量,伊文思蓝法检测脑组织血管通透性,高效液相色谱(high performance liquid chromatography,HPLC)法测定大鼠脑纹状体和海马组织腺苷三磷酸(adenosine triphosphate,ATP)、腺苷二磷酸(adenosine diphosphate,ADP)和腺苷-磷酸(adenosine monophosphate,AMP)含量。结果与平原组比较,高原缺氧环境氰化钠中毒大鼠脑组织含水量增加,纹状体和海马组织ATP和ADP含量减少,AMP含量增加。结论高原缺氧可导致大鼠脑组织腺苷酸能量代谢障碍,缺氧条件下氰化钠中毒可进一步加重脑组织能量代谢障碍,同时脑水肿也进一步加重。  相似文献   
82.
目的:研制可显影固体栓塞剂硫酸钡海藻酸钠微球.方法:采用乳化-离子交联法制备微球,正交设计优化工艺,并考察微球的粒径、形态、分布、稳定性、悬浮性、包封率及X线显影性等理化特性.结果:微球平均粒径为(53.08±32.72) μm,分散良好,形态圆整;微球100℃水浴加热2 h、-4℃冰冻24 h、37℃振摇24 h、钴60(10 kGy)照射0.5 h各组的破损率分别为(2.0±1.1)%、(86.0±19.2)%、(39.0±14.7)%和(10.3±3.2)%;0.25%海藻酸钠微球混悬液的沉降体积比为(0.92±0.018);硫酸钡投料量为2.0 g时包封率为(69.2±13.2)%,且显影效果佳.结论:海藻酸钠、壳聚糖可作为硫酸钡微球的包封材料,乳化-离子交联法适用于此微球的制备.  相似文献   
83.
The impact of selenium on the course of Hashimoto’s thyroiditis (HT) was mainly assessed by monitoring the titer of antithyroid autoantibodies in most of the studies conducted hitherto. On the other hand, the imbalance in activity of T cells such as Th1, Th2, Th17, and Treg may be relevant in the pathogenesis of this disease. Hence, the assessment of changes in the secretion of cytokines by these cells during selenium supplementation in patients with HT seems to be an important issue and was the main goal of this study. A further aim was to search for correlations among these cytokines, as well as markers of thyroid function, selenium/iodine status in the body, and other biochemical parameters. The group of 29 women with newly diagnosed Hashimoto’s thyroiditis was supplemented with selenium in a dose of 100 µg/day for 6 months. Immunological parameters: interferon γ, tumor necrosis factor α, chemokine CXCL10, interleukin 4, interleukin 1β, interleukin 17, transforming growth factor β, and C-reactive protein, as well as selenium status parameters were determined in serum twice, i.e., before and after supplementation. Selenium supplementation was associated with a change in the production of two cytokines: interferon γ and interleukin 1β, for which a decrease and an increase in concentration were observed, respectively. The partial least squares (PLS) model revealed the presence of many relevant correlations among analyzed parameters. The stage of HT development, degree of thyroid dysfunction, and selenium supplementation of diet are interdependent factors which shape the profile of some cytokines secreted by cells participating in the autoimmunity process.  相似文献   
84.
目的:采用分子吸收光度法测定万寿菊中代森锰锌残留。方法:通过蒸馏和溶液吸收实验装置,氯化亚锡催化,二乙基二硫代氨基甲酸钠分解定量产生二硫化碳气体,通过浓硫酸脱氧脱水,氢氧化钾的甲醇液吸收,用分光光度法在304 nm波长处测定其标准曲线。代森锰锌以平均相对分子质量333计,可通过平均相对分子质量计算出代谢锰锌的含量。结果:万寿菊中添加浓度为10 mg.kg-1和20 mg.kg-1(以二硫化碳计)的回收率(n=5)分别为95.9%和93.2%,RSD分别为4.8%和3.7%;最低检测限为2 mg.kg-1。结论:该方法操作简单,灵敏度高,适合大批量样品的检测。  相似文献   
85.
目的对1例支气管哮喘急性发作伴肺部感染的患者进行跟踪治疗,探讨患者在药物治疗中出现精神异常的原因。方法检索国内外关于可疑药物—孟鲁斯特钠等致精神异常的相关文献,整理相应的理论依据,为临床药物治疗提出合理建议。结果诱发精神异常等不良反应的药物较多,分析患者所用药物,锁定可疑药物孟鲁斯特钠和莫西沙星,予及时停用孟鲁司特钠,10 d后患者病情好转出院。结论有精神性疾病的哮喘患者使用孟鲁斯特钠时,需密切关注该药引起的精神异常,减少药害事件的发生。  相似文献   
86.
本文对34例囊肿采用囊腔内注射鱼肝油酸钠治疗,4例于2mo内复发而再次注射,0.5yr后随访无一复发。讨论囊肿的各种治疗方法,提出应用鱼肝油酸钠注射法治疗囊肿操作简便,效果满意,患者也乐于接受。  相似文献   
87.
Potential use of liposome for polycationic colistin is hindered by their phospholipid membrane permeability. In this study, liposomes were modified with sodium cholesteryl sulphate (Chol-SO4?) for improving the colistin loading by enhancing the colistin-bilayer electrostatic attraction. We have evaluated two liposomes: colistin-entrapped liposome of Chol-SO4? (CCL) and coated Chol-SO4?/colistin complex liposome (CCCL). In comparison with CCL which formed large aggregates at Chol-SO4?/colistin charge ratio below 2:1, CCCL showed a smaller size less dependent on the charge ratio, probably arising from more colistin entrapped on the inner leaflet of bilayer. Both liposomes exhibited significantly increased entrapment efficiency as compared with the liposome without Chol-SO4?. But colistin released upon dilution, implying free transfer of colistin through bilayers. Pharmacokinetics results showed the approximately four-fold increase in the plasma AUC0–8?h for CCCL and CCL as compared with colistin solution, showing potential benefit for infectious target localisation by prolonging the systemic circulation of colistin.  相似文献   
88.
Aim: To investigate the effect of balsalazine treatment on intestinal mucosal permeability in dextran sulfate sodium (DSS)-induced colitis and to determine the mechanism of the balsalazine-induced changes.
Methods: Experimental colitis was induced in C57BL/6J mice by the administration of 5% DSS. Balsalazine was administered intragastrically at doses of 42, 141, and 423 mg/kg. The disease activity index (DAI) score was evaluated and colon tissue was collected for the assessment of histological changes. The amount of malondialdehyde (MDA) in the colon was determined, along with the activity of myeloperoxidase (MPO), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). Mucosa from the small intestine was collected to determine the levels of tumor necrosis factor (TNF)-α and interferon (IFN)-γ. The mucosa was ultrastructurally examined with transmission electron microscopy and intestinal permeability was assayed using Evans blue.
Results: Balsalazine was found to reduce the DAI score and the histological index (HI) score, decrease the MDA content and the activity of MPO, and increase the activity of SOD and GSH-Px in colitis mice. At the same time, balsalazine ameliorated microvillus and tight junction structure, resulting in a decrease in the amount of Evans blue permeating into the intestinal wall and the levels of TNF-α and IFN-γ in colitis mice.
Conclusion: In colitis mice, the anti-colitis effect of balsalazine results in a decrease in intestinal mucosal permeability. The mechanism of this effect is partly associated with balsalazine's antioxidative and anti-inflammatory effects.  相似文献   
89.
Delta-atracotoxins (delta-ACTX), isolated from the venom of Australian funnel-web spiders, are responsible for the potentially lethal envenomation syndrome seen following funnel-web spider envenomation. They are 42-residue polypeptides with four disulfides and an "inhibitor cystine-knot" motif with structural but not sequence homology to a variety of other spider and marine snail toxins. Delta-atracotoxins induce spontaneous repetitive firing and prolongation of action potentials resulting in neurotransmitter release from somatic and autonomic nerve endings. This results from a slowing of voltage-gated sodium channel inactivation and a hyperpolarizing shift of the voltage-dependence of activation. This action is due to voltage-dependent binding to neurotoxin receptor site-3 in a similar, but not identical, fashion to scorpion alpha-toxins and sea anemone toxins. Unlike other site-3 neurotoxins, however, delta-ACTX bind with high affinity to both cockroach and mammalian sodium channels but low affinity to locust sodium channels. At present the pharmacophore of delta-ACTX is unknown but is believed to involve a number of basic residues distributed in a topologically similar manner to scorpion alpha-toxins and sea anemone toxins despite distinctly different protein scaffolds. As such, delta-ACTX provide us with specific tools with which to study sodium channel structure and function and determinants for phyla- and tissue-specific actions of neurotoxins interacting with site-3.  相似文献   
90.
低分子肝素联合奥扎格雷钠治疗急性脑梗死疗效评价   总被引:4,自引:2,他引:4  
目的评价低分子肝素联合奥扎格雷钠治疗急性脑梗死的有效性及安全性。方法将96例符合诊断标准的急性脑梗死患者随机分成3组,每组32例,分别给予低分子肝素联合奥扎格雷钠(联合组)治疗,并与单纯应用低分子肝素(低分子肝素组)和单纯应用奥扎格雷钠(奥扎格雷钠组)治疗的患者进行临床疗效、治疗前后神经功能缺损程度评分(NDS)的比较。结果治疗后联合组显效率(75%)明显优于低分子肝素组(31.3%)及奥扎格雷钠组(34.4%),NDS减分程度与低分子肝素组及奥扎格雷钠组相比,差异均有统计学意义(P<0.05,P<0.01)。结论低分子肝素联合奥扎格雷钠治疗急性脑梗死疗效显著并且安全可靠。  相似文献   
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