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排序方式: 共有302条查询结果,搜索用时 31 毫秒
141.
Hamdollah Panahpour Ali Akbar Nekooeian Gholam Abbas Dehghani 《Iranian Biomedical Journal》2014,18(4):232-238
Background: Angiotensin II (Ang II) has an important role on cerebral microcirculation; however, its direct roles in terms of ischemic brain edema need to be clarified. This study evaluated the role of central Ang II by using candesartan, as an AT1 receptor blocker, in the brain edema formation and blood-brain barrier (BBB) disruption caused by ischemia/reperfusion (I/R) injuries in rat. Methods: Rats were exposed to 60-min middle cerebral artery (MCA) occlusion. Vehicle and non-hypotensive doses of candesartan (0.1 mg/kg) were administered one hour before ischemia. Neurological dysfunction scoring was evaluated following 24 h of reperfusion. Animals were then decapitated under deep anesthesia for the assessments of cerebral infarct size, edema formation, and BBB permeability. Results: The outcomes of 24 h reperfusion after 60-min MCA occlusion were severe neurological disability, massive BBB disruption (Evans blue extravasation = 12.5 ± 1.94 µg/g tissue), 4.02% edema, and cerebral infarction (317 ± 21 mm3). Candesartan at a dose of 0.1 mg/kg, without changing arterial blood pressure, improved neurological dysfunction scoring together with significant reductions in BBB disruption (54.9%), edema (59.2%), and cerebral infarction (54.9%). Conclusions: Inactivation of central AT1 receptors, if not accompanied with arterial hypotension, protected cerebral micro-vasculatures from damaging effects of acute stroke. Key Words: Blood–brain barrier, Brain edema, AT1 receptor, Candesartan 相似文献
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Maryam Ebrahimiyan Mohammad Mahdi Majidi Aghafakhr Mirlohi Abbas Noroozi 《Euphytica》2013,190(3):401-414
The physiological basis of genetic variation in drought response and its association with yield and related indices is not clear in tall fescue. In this study thirty genotypes of tall fescue (Festuca arundinacea Schreb.) were sampled from a polycross population and evaluated under two levels of irrigation in 2010 (normal and intense stress) and 2011 (normal and mild stress). Physiological traits including relative water content (RWC), total chlorophyll (TChl), chlorophyll a (Chla), chlorophyll b (Chlb), Chla/Chlb, carotenoids (Car), TChl/Car and proline content along with forage yield, agro-morpholgical traits and selection indices (stress tolerance index, STI and drought susceptibility index, DSI) were studied. Large variation and moderate to high heritability was estimated for most of the studied traits. Intense drought condition decreased chlorophyll content while mild stress significantly increased it. In the other hand intense drought stress increased Chla/b while mild stress didn’t change it. Under mild drought stress condition STI was positively correlated with RWC while under intense drought stress condition STI was positively correlated with chlorophyll content. Although proline content was significantly increased in both intense and mild drought stress conditions, no relationship was found between proline accumulation with forage yield and STI. Applications of principle component analysis for screening suitable genotypes are also discussed. 相似文献
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乌鲁木齐南郊亚花松萝重金属含量及其大气污染评价的研究 总被引:2,自引:2,他引:0
[目的]利用地衣评价乌鲁木齐南郊空气质量.枝状地衣对空气中的要害气体非常敏感,具有体内富集作用,近年来地衣广泛的应用在空气质量评价中.[方法]采用地衣移植方法,从乌鲁木齐南山八一林场选择亚花松萝,移植到乌鲁木齐南郊的红雁池电厂、新疆大学校园、乌鲁木齐市动物园和乌鲁木齐市人民公园等4个不同点.移植后1和3个月后别取样,应用电感耦合等离子光谱直读法对移植地衣体内的Al、Cr、Cu、Fe、Mn、Ni、Zn等7种元素含量进行测定.[结果]亚花松萝体内被测定出的重金属元素种类和含量与移植时间之间存在显著性差异.随着地衣移植时间的延长被检测出的元素种类及含量明显增加,其中Al、Cr、Cu、Mn的含量在各移植点之间有显著性差异.[结论]亚花松萝重金属含量在生物评价乌鲁木齐南郊空气污染方面具有一定的研究价值. 相似文献
146.
Z Akhlaghi JI Mobarakeh M Mokhtari H Behnam AA Rahimi MS Khajeh Hosseini F Samiee 《Iranian Biomedical Journal》2012,16(2):107-112
Background: Initial studies have shown that low-energy ultrasound stimulates living tissue cells to reduce regeneration or speed up their recovery. The purpose of this study was to examine the effects of various ultrasound parameters on the speed of recovery in injured sciatic nerves NMRI.Methods: NMRI mice (n = 200) with injured left paw, caused by crushing their sciatic nerves, were randomly selected. The animals were exposed to ultrasound radiation with various frequencies, intensities, and exposure time. They were allocated into 20 groups (19 treatment and 1 control groups). Sciatic functional index (SFI) test was used to evaluate the difference between the groups with respect to functional efficiency of the sciatic nerve and its recovery. SFI ، (P=0.000).Results: The results of SFI test obtained from the 14th day showed a significant difference among the groups (P<0.05). On the 14th day after treatment, one of the groups (US11) recovered up to 90%..Conclusion: Altered ultrasound exposure parameters had more favorable outcomes compared with our previous work.Key Words: Sciatic nerve, Ultrasonic therapy, Regeneration 相似文献
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149.
Tanzeela Fazal Bushra Ismail Asad Muhammad Khan Rafaqat Ali Khan Amir Abbas Shah Naqvi Farrukh Siyar Hamid 《Communications in Soil Science and Plant Analysis》2016,47(1):11-18
The present study deals with the effects of addition of sulfur along with other acidifying agents for their ability to lower and maintain the pH in a given range for a longer period of time. The chemicals were subjected to batch test individually and in combinations. Treatments were applied to three soils of different textures: sandy clay loam, clay loam, and silt loam. A 1:1 soil/water paste along with the added amendment was maintained at room temperature for 2 months. Most of the chemical treatments lowered the pH significantly. Combinations containing S/Al2(SO4)3/H2SO4, S/Al2(SO4)3/H2O2, and S/H2O2/H2SO4 were found to be very effective in lowering the pH. The soil pH remained acidic for 2 months, indicating the suitability of chemically amended soil for the plantations requiring acidic soil pH. 相似文献
150.
Bhatti SA Ahmed MF Wynn PC McGill D Sarwar M Afzal M Ullah E Khan MA Khan MS Bush R Warriach HM Khan A 《Tropical animal health and production》2012,44(4):819-826
The objective was to study the growth potential of Sahiwal calves given milk or milk replacer with or without concentrates. For this purpose, forty-eight Sahiwal calves were divided into four groups of 12 animals each with equal sex ratio. In each group, the calves were offered either milk or a milk replacer (MR) at a rate of 10% of their body weight adjusted weekly. In addition to this, calves were fed either a starter ration plus Egyptian clover hay (SR + H) or hay only (H) until the end of trial. The milk or MR was withdrawn gradually from day 56 until animals were weaned completely by day 84. Calves offered milk grew faster than those offered MR (357 ± 9 vs. 162 ± 9 g/day; p < 0.05) and displayed higher weaning weights (51.6 ± 0.8 vs. 35.2 ± 0.8 kg; p < 0.05). The calves offered SR + H grew faster (311 ± 9 vs. 208 ± 9 g/day; p < 0.05) and displayed higher weaning weights (48.7 ± 0.8 vs. 38.1 ± 0.8 kg; p < 0.05) than those fed H alone. Calves offered milk plus SR + H showed the highest growth rate and weaning weights (401 ± 13 g/day and 56.3 ± 1 kg, respectively). The lowest growth rate and weaning weights were observed in calves offered MR and H only (115 ± 13 g/day and 30.3 ± 1 kg, respectively). Calves offered the MR had higher number of scour days than those offered milk (13.5 vs. 3.3). The feeding of whole milk in combination with the starter ration and hay resulted in superior growth rates, higher weaning weights, and healthier calves than the other feeding regimens. 相似文献