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71.
目的 探讨自发性高血压大鼠(spontaneously hypertensive rats,SHR)和正常血压大鼠(Wistar-Kyoto rat,WKY)饲喂高盐饮食后脑出血特点及脑微血管结构改变.方法 6周龄雄性SHR和WKY大鼠各60只分别通过随机数字表分为两组,一组饲喂高盐饮食,一组饲喂常规饮食,每周测1次尾动脉收缩压,观察大鼠行为学改变、存活情况、神经功能缺损并评分,HE染色观察脑出血后血肿特点,干湿质量比法测定脑含水量,伊文氏蓝(Evans blue,EB)检测血脑屏障通透性,免疫荧光染色观察脑微血管改变,透射电镜观察脑微血管超微结构和紧密连接改变.结果 与两组常规饮食大鼠相比,两组高盐饮食大鼠均出现血压升高、神经功能缺损症状,脑含水量和血脑屏障通透性增加,HE染色可见血管周围出现圆形渗出性出血,免疫荧光染色显示脑血管呈断续性改变,透射电镜可见脑血管与周围组织间隙增宽,紧密连接消失,管壁厚薄不均,出现空泡样改变.SHR所有改变较WKY显著(P<0.01).高盐饮食SHR 18周龄时全部死亡,高盐饮食WKY 19周龄时全部死亡,常规饮食大鼠均正常存活.结论 高盐可单独引起大鼠血压升高、脑微血管结构改变,高血压可加重大鼠脑微血管损伤,两者可共同促进大鼠脑出血发生. 相似文献
72.
目的:观察丹参多酚酸盐联合尿激酶治疗急性S T段抬高型心肌梗死后心绞痛的疗效及安全性。方法将124例患者分成治疗组和对照组,每组62例。两组均给予冠心病二级预防治疗及溶栓治疗(尿激酶150万U溶于生理盐水100 m L中30 min内滴完),随后对照组给予极化液治疗,治疗组给予丹参多酚酸盐200 mg稀释于5%葡萄糖或生理盐水250 mL中静脉滴注15 d。观察两组心肌梗死后心绞痛发生情况、疗效及安全性。结果治疗组心绞痛发生率为25.81%,对照组心绞痛发生率为56.45%,两组比较差异有统计学意义( P<0.05)。结论应用丹参多酚酸盐联合尿激酶治疗急性S T段抬高型心肌梗死,可以显著减少心肌梗死后心绞痛,临床疗效好,不良反应少,安全性好。 相似文献
73.
目的 通过对决明子萌发及幼苗生理特性的研究,寻找提高决明子及幼苗在盐胁迫条件下抗性能力的途径。方法 测定盐胁迫下决明子在经过不同质量浓度的外源性5-氨基乙酰丙酸(ALA)处理后,种子的发芽势、发芽率、发芽指数和活力指数,并对决明幼苗叶片叶绿素量、叶绿素荧光参数、原生质膜透性、叶片丙二醛(MDA)量、可溶性糖量、可溶性蛋白量及脯氨酸量及超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性进行测定。结果 100 mmol/L盐胁迫下的决明子萌发受到显著抑制,但是经过不同质量浓度的ALA处理后,萌发指标均有升高。结果表明,外源性ALA处理显著提高了决明子发芽势、发芽率、发芽指数和活力指数,提高了叶片叶绿素a、叶绿素b和总叶绿素量,显著提高了最大光化学效率(Fv/Fm),PSII有效光化学效率(Fv′/Fm′),PSII实际光化学效率(ΦPSII),光化学淬灭系数(qP),降低了原生质膜透性、叶片的MDA量及非光化学淬灭系数(NPQ),提高了盐胁迫下幼苗叶片可溶性糖、可溶性蛋白和脯氨酸量,显著提高了叶片SOD、POD、CAT活性。结论 外源性ALA通过提高决明子的萌发指数,提高幼苗光合效率、渗透调节物质量及抗氧化酶活性,有效地减缓盐胁迫对决明子及幼苗产生的伤害,提高种子及幼苗的抗盐能力。 相似文献
74.
Salt (NaCl), as a by-product from the potash and desalination industry, can be the solution to the scarcity of building materials and might replace more energy-consuming materials. However, salt carries the risk of deliquescence in humid environments. This study conducted fundamental research on the hygrothermal performance of salt for internal surface applications in the building envelope in six different climate conditions. In addition, salt’s performance was also compared with that of gypsum in similar applications. The simulation models (using WUFI®Pro, WUFI®Plus) and in situ measurements were applied to investigate the hygrothermal consequences of the incorporation of salt on the thermal envelope, indoor environment, and energy consumption. Our studies revealed that salt provided the best hygrothermal responses without Heating, Ventilation, and Air Conditioning (HVAC) in very hot-dry and the worst in very hot-humid climates. With an energy-efficient thermal envelope and HVAC, salt can also find an indoor application in temperate, continental, and subpolar climates. In comparison to gypsum, salt has a slightly higher energy demand (heating, cooling, and dehumidification) due to its higher thermal conductivity and moisture resistance. This study fills the knowledge gap on salt’s hygrothermal performance and shows the potential in its utilization. 相似文献
75.
目的:分析探讨中枢性低钠血症的诊断及处理方法。方法:回顾性分析我科近5年收治的32例中枢性低钠血症患者诊治经过。结果:本组5例符合抗利尿激素分泌异常综合征(SIADH),27例符合脑性耗盐综合征(CSWS),全部患者低钠血症在1-2周内均得到纠正。结论:神经外科疾患并发中枢性低钠血症应密切监测血钠、中心静脉压及24h尿钠水平,并以此为依据鉴别其类型,给予有效治疗。 相似文献
76.
目的:优选盐炙沙苑子炮制工艺,为盐炙沙苑子规范化生产和质量保证提供依据。方法:以沙苑子苷A和鼠李柠檬素为指标,采用HPLC法,以加盐量、炒制温度和炒制时间为考察因素,采用正交试验法L9(3^4)优选盐炙沙苑子的最佳炮制工艺。结果:盐炙沙苑子的最佳炮制工艺为:加盐量为2%,炒制温度控制在120~130℃,炒制时间为60s。结论:优选出的盐炙沙苑子炮制工艺稳定可行,重现性好。 相似文献
77.
目的:探索Salacinol全合成的基本步骤。方法:根据Salacinol的结构组成,设计了其结构类似简化物1-(3-磺氧丙基)四氢噻吩锍盐(2)。以四氢噻吩和3-碘基丙醇为原料,经偶合反应和三氧化硫吡啶的酯化制得化合物2。当在相同的条件下以3-碘基丙醇硫酸酯钠替代3-碘基丙醇为烷化剂时,其主要产物经确证为3-碘基丙醇硫酸酯钠的分子内环化物1,4-丙二醇硫酸内酯(7)。结果:上述模拟实验结果提示,通过两步反应制得化合物2的方法可能为Salacinol的全合成提供一种新的途径。 相似文献
78.
Nur Aziah Hanapi Ahmad Saifuddin Mohamad Arshad Jafri Malin Abdullah Tengku Sifzizul Tengku Muhammad Siti R. Yusof 《Journal of pharmaceutical sciences》2021,110(2):698-706
Neurotherapeutic potentials of Centella asiatica and its reputation to boost memory, prevent cognitive deficits and improve brain functions are widely acknowledged. The plant's bioactive compounds, i.e. asiaticoside, madecassoside and asiatic acid were reported to have central nervous system (CNS) actions, particularly in protecting the brain against neurodegenerative disorders. Hence, it is important for these compounds to cross the blood-brain barrier (BBB) to be clinically effective therapeutics. This study aimed to explore the capability of asiaticoside, madecassoside and asiatic acid to cross the BBB using in vitro BBB model from primary porcine brain endothelial cells (PBECs). Our findings showed that asiaticoside, madecassoside and asiatic acid are highly BBB permeable with apparent permeability (Papp) of 70.61 ± 6.60, 53.31 ± 12.55 and 50.94 ± 10.91 × 10?6 cm/s respectively. No evidence of cytotoxicity and tight junction disruption of the PBECs were observed in the presence of these compounds. Asiatic acid showed cytoprotective effect towards the PBECs against oxidative stress. This study reported for the first time that Centella asiatica compounds demonstrated high capability to cross the BBB, comparable to central nervous system drugs, and therefore warrant further development as therapeutics for the treatment of neurodegenerative diseases. 相似文献
79.
《Scandinavian journal of primary health care》2013,31(4):300-306
Objective - To review current knowledge about excess dietary salt as a risk factor for diseases and to compare and discuss the national policies for dietary salt in the Nordic countries.Design - Literature review, questionnaire and interviews. Nordic comparative study.Setting - the Medline bibliographic system and authorities responsible for the national nutritional policies in the Nordic countries.Subjects - Scientific articles published since 1988 concerning the impact of excess dietary salt on health and key persons with responsibilities for the formulation of national recommendations about dietary salt in each of the five Nordic countries.Main outcome measures - Articles dealing with (i) epidemiological observations, (ii) sensitive groups, (iii) underlying biological mechanisms concerning the contents of the latest national recommendations and the wording of legislation and decrees about salt in food-stuffs in the Nordic countries.Results - the impact of excess dietary salt on health mainly concerns hypertension, gastric cancer, osteoporosis and bronchial hyperreactivity. the national policy for dietary salt in Finland differs from the other Nordic countries. in Finland salt is a food additive and a variety of special regulations exist. Finland has chosen a more active way to achieve the existing Nordic recommendation of 5 g salt per day. the daily intake is about 10 g per day in all the Nordic countries.Conclusions - There is need for further epidemiological studies of the relationship between excess dietary salt and gastric cancer, osteoporosis, and bronchial hyperreactivity. the knowledge of the relationship between dietary salt and raised blood pressure is sufficient to put force behind the implementation of existing Nordic recommendations. 相似文献
80.