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21.
Delta oscillations, characteristic of the electroencephalogram (EEG) of slow wave sleep, estimate sleep depth and need and are thought to be closely linked to the recovery function of sleep. The cellular mechanisms underlying the generation of delta waves at the cortical and thalamic levels are well documented, but the molecular regulatory mechanisms remain elusive. Here we demonstrate in the mouse that the gene encoding the retinoic acid receptor beta determines the contribution of delta oscillations to the sleep EEG. Thus, retinoic acid signaling, which is involved in the patterning of the brain and dopaminergic pathways, regulates cortical synchrony in the adult.  相似文献   
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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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The aims of this study are to assess, in a power station in Shiraz, the effects of noise and electromagnetic field on psychological mood. By the great industrial and technological improvements human beings have been exposed to different types of physical and chemical factors. Some of these factors such as electromagnetism are known as the constant components of the environment. According to the studies carried out in one of the power stations in Shiraz, psychological disorders caused by jobs are among the most important problems of the workers. This study is performed to determine the presence or absence of these psychological disorders. This cross-sectional study is performed on these groups : (1) The gas power plant staff who were in contact with electromagnetic field and nose, (2) employees who were only exposed to noise and (3) a group of staff employed in the administrative parts of the Telecommunication companies who did not have any history of being exposed to electromagnetic field and sounds. The General Health Questionnaire (GHQ) is used in this study to recognize psychosomatic disorders. Measurements indicate that range of electromagnetic field varies from 0.087 micro Tesla in the phone homes to 30 micro Tesla in power stations. The results of this study has shown that a significant number of staff which were exposed to electromagnetic fields and noise (78.2%) were suspected to have a kind of mental disorders. The results obtained from this study which shows the prevalence of mental disorders among the suspected case is higher than the results of Noorbala and colleagues study in 2006.  相似文献   
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The anatomy of ovine salivary glands was studied on cadaver heads. The mandibular duct enters the oral cavity on the ventral surface of sublingual caruncles, which are located medial to the orifice of the ventral sublingual gland duct. The parotid gland duct enters the oral cavity on the cheek opposite the upper 2nd molar. Prior to applying sialography to live animals, the procedure was carried out on cadaver heads then the live animals were sedated, the mandibular and parotid ducts catheterized and contrast medium was injected into each gland. Lateral radiographs were made immediately after the injection. The normal sheep mandibular and parotid salivary glands have a multilobular appearance in cadaver heads, but in live animal only the ducts and their smaller branches could be identified. The mean diameter of mandibular and parotid duct were 1.4+/-0.3 mm and 3. 1+/-1.0 mm respectively. The monostomatic sublingular gland had a slender shape in the sialogram. In conclusion sialography of mandibular, parotid and sublingual salivary glands in sheep is practical and can be helpful in diagnosis of pathological conditions of these glands.  相似文献   
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This study was conducted to generate genetic information in rice varieties based on a complete diallel crosses over two years. The results indicated that genotype effect was significant for all traits. Genotype × environment interaction effects were significant only for cooked grain length (CGL) and cooked grain shape (CGSH). General combining ability (GCA) and specific combining ability (SCA) effects were significant for entire traits, which indicated the important roles of both additive and non-additive gene actions. GCA x environment interaction effects were significant for CGL, CGSH and grain elongation index (GEI). In the controlling of the inheritance of milled grain shape (GSH), milled grain width (MGW), GEI, milled grain length (MGL), CGSH and cooked grain width (CGW), the additive gene effects were more important than non-additive one. The average degree of dominance was within the range of partial dominance for all of the traits. The narrow-sense heritability was ranged from 0.65 (GSH) to 0.36 (CGL). GCA effects were significant for all of the parents in milled grain length and it was significant for some of the parents in other traits. The crosses of Deilmani × IRFAON-215 exhibited significant SCA for GEI. The positive mean of heterosis was observed for CGW. The highest maximum values of heterosis were revealed in GEI, flowed by GSH, MGW and CGW. GCA and MPV were significantly and positively correlated together for all traits.  相似文献   
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This study was conducted to generate genetic information in rice varieties based on a complete diallel crosses over two years. The results indicated that genotype effect was significant for all traits. Genotype × environment interaction effects were significant only for cooked grain length (CGL) and cooked grain shape (CGSH). General combining ability (GCA) and specific combining ability (SCA) effects were significant for entire traits, which indicated the important roles of both additive and non-additive gene actions. GCA x environment interaction effects were significant for CGL, CGSH and grain elongation index (GEI). In the controlling of the inheritance of milled grain shape (GSH), milled grain width (MGW), GEI, milled grain length (MGL), CGSH and cooked grain width (CGW), the additive gene effects were more important than non-additive one.The average degree of dominance was within the range of partial dominance for all of the traits. The narrow-sense heritability was ranged from 0.65 (GSH) to 0.36 (CGL). GCA effects were significant for all of the parents in milled grain length and it was significant for some of the parents in other traits. The crosses of Deilmani × IRFAON-215 exhibited significant SCA for GEI. The positive mean of heterosis was observed for CGW. The highest maximum values of heterosis were revealed in GEI, flowed by GSH, MGW and CGW. GCA and MPV were significantly and positively correlated together for all traits.  相似文献   
30.
Since wheat and other annual cereal crops are often harvested for forage instead of grain in California, replacing them with perennial crops could save energy and reduce the release of heat-trapping gases. To assess the potential for perennial crops based on wheat, biomass yield and stand persistence were studied for nine wheat×wheatgrass amphiploids (8x to 14x) and five wheatgrass species (2x to 10x) over three seasons in the Central Valley, California. The 8x and 10x amphiploids died after one biomass harvest and a single summer period. In contrast, the 14x amphiploids, which were sterile, continued producing biomass over the entire period of the trial. They were also highly salt-stress tolerant with little decline in biomass production in response to an increase in salinity from 100 and 250 mM NaCl in a solution-culture study. The development of a salt-stress-tolerant perennial crop based on wheat for the California-type climate will require either a substantial improvement in perennial growth of low-ploidy (8x) amphiploids or the development of technology for efficient vegetative propagation of the sterile high-ploidy (14x) amphiploids.  相似文献   
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