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231.
AIM:To observe the effects of taurine-zinc (TZC) on the learning and memory abilities of vascular dementia (VD) mice and to investigate the related mechanism. METHODS:The mice were randomly divided into model group, sham group, and TZC at 50 mg/kg, 100 mg/kg and 200 mg/kg groups. The mice in drug groups were given TZC by gavage at 10 mL/kg once daily. The mice in sham group and model group were given equal volume of distilled water. VD mice were established by intercepting both common carotid arteries and bleeding at caudal vein after 14 d of gavage. The levels of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) were detected by ELISA. The levels of inducible nitric oxide synthase (iNOS) and nitric oxide (NO) were measured via spectrophotometer. Step-down test and Morris water maze test were used to examine the abilities of learning and memory in the mice. RESULTS:TZC at 50 mg/kg, 100 mg/kg and 200 mg/kg reduced the levels of TNF-α, IL-1β, iNOS and NO in the brain tissues. In the water maze test, TZC at 100 mg/kg and 200 mg/kg significantly decreased the error times and latency compared with model group. In the step-down test, the escape latency was prolonged and error times were lowered significantly by treatment with TZC at 50 mg/kg, 100 mg/kg and 200 mg/kg as compared with model group. CONCLUSION:TZC improves the abilities of learning and memory, which might be related to the reduction of TNF-α, IL-1β, iNOS and NO levels in VD mice.  相似文献   
232.
津优48号是以优良自交系P-1和D59-1-1配制而成的黄瓜一代杂种,植株长势中等,叶片中等大小,叶色绿.主蔓结瓜为主,坐瓜率高,畸形瓜率低.瓜色深绿,有光泽,瓜条长35 cm左右,单瓜质量230 g左右,瓜把小于瓜长的1/7,瓜腔小于瓜横径的1/2,口感脆甜.经人工接种抗病性鉴定,高抗黄瓜枯萎病、霜霉病和白粉病,抗病...  相似文献   
233.
鸡实验性急性有机磷中毒血清酶活性变化分析   总被引:1,自引:0,他引:1  
选取临床健康体质量为0.8±0.07kg的三黄肉鸡24只,随机分成3个试验组和1个对照组,每组6只,其中试验、和组分别皮下一次注射氧乐果攻毒,剂量分别为35mg/kg体质量、70mg/kg体质量和140mg/kg体质量;对照组注射生理盐水。攻毒后系统观察动物急性有机磷中毒症状,采血测定体内胆碱酯酶(CHE)、碱性磷酸酶(ALP)、乳酸脱氢酶(LDH)、谷丙转氨酶(ALT)以及谷草转氨酶(AST)的活力。试验结果表明:鸡急性有机磷中毒主要表现为精神沉郁,共济失调,口角大量流涎,呼吸困难,严重腹泻和粪便带血等临床症状。攻毒组CHE3活性显著低于对照组,ALP的活性也有所降低,LDH活性升高,但ALT和AST的活性无显著变化。  相似文献   
234.
为了研究阶段水分亏缺(亏水+不亏水WLWH、不亏水+亏水WHWL、亏水+亏水WLWL、不亏水+不亏水WHWH)和不同施氮量(NZ:0,NL:0.2 g/kg,NH:0.4 g/kg)对小桐子生长、生理指标和灌溉水利用效率的影响,通过盆栽试验,发现WLWH的生长和灌溉水利用效率均显著高于WHWL;作物的灌溉水利用效率随施氮量的增大而呈现先增大后减小的趋势,在NL水平下达到最大值;与高水高氮的处理NHWHWH相比,中水低氮处理NLWLWH节约灌溉水27%,节约氮肥使用量50%,小桐子株高减少31%、总干物质量减少35%,灌溉水利用效率减少13%,但茎粗增加13%,根冠比增加20%.可见小桐子在第一阶段处理(40~90 d)幼树期对水分的需求量较小,适度的亏缺灌溉可提高灌溉水利用效率;小桐子在第二阶段处理(90~140 d)处于旺长期,对水分的需求量较大,增大灌水量可大幅度促进小桐子生长及其干物质量的积累.全生育期实施亏缺灌溉,可提高小桐子自身适应外界环境能力,抗干旱胁迫能力也逐渐增强,但WLWL水平下的小桐子生长缓慢.经综合分析,认为处理NLWLWH可作为干旱地区条件下的小桐子灌溉和施氮制度.  相似文献   
235.
采用田间试验方法,研究不同类型有机肥对石油醚提取物及香气物质含量的影响。结果表明:1)施用有机肥均能增加石油醚提取物含量,其中T3(无机化肥+芝麻饼肥+生物有机肥)处理的中、上部叶石油醚提取物含量最大,分别为7.76%、8.75%;2)施用有机肥处理对上部叶的增香效果优于中部叶,有机肥处理的上部叶有24种香气物质含量均高于CK,中部叶有18种高于CK;其中T3处理的中、上部叶致香物质总量最大,分别高达1 291.45、1 524.34μg/g,较CK处理分别增加3.32%、34.86%。  相似文献   
236.
采用PCR产物直接测序的方法获得肌肉生长抑制素(myostatin,MSTN)基因的编码区序列,并运用生物信息学方法对该基因编码蛋白的理化性质、信号肽、跨膜结构、二级结构、三级结构和功能结构域进行分析。结果表明,三穗鸭MSTN蛋白是一个疏水性不稳定蛋白,作为信号肽的可能性很大;含有22个α螺旋、26个β折叠、26个T转角、20个无规则卷曲,有1个跨膜结构,具有TGF-β的主要结构。研究结果为MSTN基因的进一步研究提供参考。  相似文献   
237.
为研究胡麻异质型乙酰辅酶A羧化酶BCCP、BC、α-CT和β-CT四个亚基基因的生物学功能,采用基因克隆、生物信息学和RT-PCR技术分别对胡麻accA、accB、accC和accD 4个基因进行分析。结果发现陇亚10号accA基因编码α-CT亚基,CDS序列全长为2364 bp,编码787个氨基酸;accB基因编码BCCP亚基,CDS序列全长为1173 bp,编码275个氨基酸;accC基因编码BC亚基,CDS序列全长为1574 bp,编码527个氨基酸;accD基因编码β-CT亚基,CDS序列全长为1137 bp,编码378个氨基酸,且4个基因编码的蛋白都是脂肪酸系数较高的亲水性蛋白。RT-PCR结果表明,胡麻accA、accB、accC和accD 4个基因在3个胡麻品种(高含油量的张亚2号、中含油量的陇亚10号和低含油量的R2-17)的不同时期不同组织的表达模式不同,accA、accB、accC和accD四个基因在R2-17、陇亚10号和张亚2号3个胡麻品种所有时期的不同组织中均有表达,但在种子中的表达量均明显高于其他组织,尤其在种子发育10~25 d油脂快速积累时期,4个基因的表达量都迅速增加并达到最高峰。研究表明异质型乙酰辅酶A羧化酶基因可能调控胡麻种子发育前期油脂的合成积累。  相似文献   
238.
AIM: To determine the effect of exogenous phosphocreatine (PCr) at different concentrations on transient outward potassium (Ito) current in rat ischemic ventricular mid-myocardial (M) cells and to explore the antiarrhythmia mechanism in the treatment of ischemic heart disease. METHODS: M cells were isolated enzymatically from left ventricular mid-myocardium of rats. Peak Ito current was recorded by patch-clamp technique in the whole-cell configuration when M cells were superfused with normal Tyrode solution, simple ischemic solution,and simulated ischemic solution containing PCr at concentrations of 5, 10, 20 and 30 mmol/L for 10 min. RESULTS: Peak Ito current density of M cells superfused with simple simulated ischemic solution was significantly reduced by (76.1?6.3)% (P<0.05) compared with M cells superfused with Tyrode solution. Ischemic solution containing 5, 10, 20 and 30 mmol/L PCr reduced peak Ito current density by (57.1?9.6)% (P<0.05), (40.3?10.3)% (P<0.05), (34.3?9.6)% (P<0.05) and (32.1?10.6)% (P<0.05),respectively. There was statistical difference among ischemic solution without PCr and containing PCr at concentrations of 5 and 10 mmol/L groups (P<0.05). No statistical difference among groups of 10, 20 and 30 mmol/L PCr was observed (P>0.05). CONCLUSION: PCr reverses the inhibition of Ito current under ischemic condition in M cells, which may be the mechanism responsible for arrhythmia prevention in ischemic heart disease. PCr at concentrations of 0~10 mmol/L exerts significant dose-effect relationship.  相似文献   
239.
AIM: To investigate the effects of puerarin on blood pressure in renovascular hypertensive rats, and to measure puerarin-induced changes of apelin-12, angiotensin II (Ang II) and nitric oxide(NO), the factors related to development of hypertension. METHODS: Sixty-five male Sprague-Dawley rats were used, of which 8 rats were randomly selected as sham operation group, and the remaining were used to make two-kidney, one-clip model. The rats that met the criterion for Goldblatt hypertensive rat model were randomly allocated into 5 groups: high-, middle- and low-dose puerarin groups, captopril group, and model group. The drugs were administered for 6 weeks. Blood pressure was measured every 2 weeks. Six weeks after treatment, all rats were sacrificed under deep anesthesia. Blood and kidney samples were collected. The level of apelin-12 in serum and kidneys was detected by ELISA. The level of Ang II in plasma and kidneys was measured by radioimmunoassay. NO level in serum was examined by nitrate reductase assay. RESULTS: Puerarin had an antihypertensive effect in a dose-dependent manner. Marked decreases in the level of serum apelin-12 in high- and middle-dose puerarin groups were observed(P<0.01). Puerarin at low dose did not cause obvious change in the content of apelin but still reached significant level (P<0.05). As the dose of puerarin went up, the level of apelin-12 in the kidneys was gradually decreased. Puerarin at high and middle doses obviously reduced the level of AngII in plasma, while purarin at low dose did not produce any significant effects. Puerarin at high and middle doses markedly increased the level of NO in serum, but puerarin at low dose did not induce any significant changes. CONCLUSION: Puerarin has an antihypertensive effect, and its mechanism may be related to inducing the changes of apelin, Ang II and NO, and regulating the balance among those factors.  相似文献   
240.
对湖北省福寿螺(Pomacea canaliculata)分布地区进行了调查,并确认福寿螺在湖北省的北缘分布地区为宜昌市夷陵区黄柏河—远安县洋坪镇(凤凰村)—荆州市沙市区八岭山镇(童桥村)—潜江市渔洋镇(排湾村)—孝感市孝南区三汊河镇(龙岗村)—武汉市黄陂区前川街(下石村)—英山县红山镇(东汤河村)一线,纬度30°~31°,其中最北端分布地区为远安县洋坪镇,东经111°34′57.97″,北纬31°11′3.36″。湖北省福寿螺分布地区的立地条件均同时具备一定深度水体(深10 cm以上)和一定深度的淤泥(深10 cm以上),且可能覆盖度较高的水生植被更有利于福寿螺越冬。讨论了福寿螺对环境的适应能力和福寿螺北缘分布地区继续北移扩展的可能性问题。长江上游地区及湖南省福寿螺资源不仅增加湖北省福寿螺为害风险,而且增加湖北省福寿螺的防控压力。  相似文献   
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