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Effects of immobilization and footshock stress on locomotor activity in different areas of an open field were examined in mice. Center region activity, peripheral region activity and total activity were used as measurement indices. These results indicate that both immobilization and footshock stress significantly increased total activity across 24 min of behavioral testing. Further analyses revealed that the difference in total activity between the experimental and control groups were mainly attributal to an increase in center region activity. Both stress manipulations markedly augmented peripheral region activity for only the first 6 min. More important, when the proportion of center to peripheral activity was used as an index, both experimental groups manifested an inverted U shape relationship with the maximum effect occurring between 13-18 min of behavioral testing. Similarities of these activity measures in response to different stressors suggests that common neurochemical and/or neurohormonal mechanisms may mediate these behavioral changes.  相似文献   
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Transmission electron microscopic investigation of standardized fractures of radii in 50 rabbits re vealed that fibroblasts took part in the formation of bony callus. The osteogenetic role played by the fibroblasts can be categorized into the following 5 aspects: a. Fibroblasts synthesize and secrete Type collagen fibrils and induce deposition of calcium salt crystals in the collagen fibrils. b. Fibroblasts produce matrix vesicles in their surroundings. These matrix vesicles become calcified and turn into floccu- lent calcospherules which coalesce and fuse into bone tissues. c. Fibroblasts harbor calcium granules in their mitochondria, thus providing calcium for calci- fication of the intercellular matrix and bone forma tion between the cells. d. Fibroblasts can transform directly into osteocytes; there is bone formation around the fibroblasts, the bone tissues surround the fibroblast in the form of bony lacuna, then the fibro- blast in the lacuna transforms into osteocyte. e. Fibroblasts can undergo degenerative changes leading to decease and replacement by bone tissues.  相似文献   
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1. In chloralose-urethane anaesthetized cats, the dorsal cardiovascular reactive area (DCRA) in the parvocellular reticular nucleus dorsomedial to the facial nucleus, and the ventral cardiovascular reactive area (VCRA) ventromedial to the facial nucleus, were stimulated by microinjections of sodium glutamate (100–200 nmol) or electric current. 2. Stimulation of DCRA, with a long latency of 15–20 s, elicited a marked increase of blood flow in the contralateral femoral artery with little change to moderate increase in systemic arterial blood pressure (ABP). In the relatively dorsal portion of DCRA, however, a smaller increase of blood flow in the ipsilateral femoral artery was elicited. 3. On the other hand, stimulation of VCRA with a short latency (3–5 s) evoked an increase of blood flow in both femoral arteries which was more prominent on the contralateral side. The responses were accompanied with decreases in the blood flow of other vascular beds with only a slight increase or minimal change in ABP. 4. The data suggest that DCRA and VCRA are both viscerotopically organized to alter the resistance of individual vascular beds for redistribution of blood flow.  相似文献   
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The present study was carried out with the aim of elucidating the effect of administration of antioxidants vitamin E, Rubiside, and Rubiquinone on neutrophil function in burns. The experimental results showed that the survival rates of the animals were higher in antioxidant Rubiside and Rubiquinone treatment groups, as compared with control group 7 days post-burn. In the control group, Superoxide dismutase (SOD) activity of blood was markedly decreased, malondialdehyde (MDA) levels in serum were sharply increased, neutrophil chemiluminescence (PMN-CL), neutrophil (PMN) phagocytic rate and phagocytic index were markedly decreased (P less than 0.05) after fluid resuscitation for the observation period of 7 days, as compared with that before resuscitation. It was also found that significant negative correlation existed between MDA levels of serum and PMN phagocytic rate (P less than 0.01) in the control group. On the contrary, after the administration of antioxidant agent vitamin E, Rubiside or Rubiquinone in three different groups, SOD activity was markedly higher, MDA levels were markedly lower, and PMN-CL, PMN phagocytic rate were higher as compared with that of the control group. The experiment suggests that antioxidants could be used as an adjunct in the resuscitation of burn shock, especially in cases when resuscitation is delayed because of various reasons.  相似文献   
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运用二元碱氮置换吸附红外光谱法、分子筛孔径分布测定技术、XPS技术,考察了丝光沸石表面酸性与孔结构的相互关系、钯在丝光沸石上分布情况和价态及其与沸石的相互作用。结果表明,随着丝光沸石脱铝程度的增加,表面出现大量不规整晶格,存在较多的次级孔道。强质子酸中心主要分布在它的“外表面”。钯在其表面富集,并与“外表面”上的质子酸中心协同作用,促进了轻质烷烃异构化反应。  相似文献   
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作者用红细胞C_3b受体花环试验和红细胞免疫复合物花环试验对马桑内酯所致癫痫发作大鼠红细胞免疫粘附功能的变化进行了观察,结果表明,癫痫组动物红细胞C_3b受体花环率明显低于对照组,而红细胞免疫复合物花环率相差不显著.提示癫痫发作可导致大鼠红细胞免疫粘附功能降低,因此在癫痫治疗中注意调整和增强患者的红细胞免疫功能具有重要意义。  相似文献   
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This multiclinic study was performed to evaluate the safety and efficacy of metaproterenol sulfate (Alupent) metered dose inhaler in children with asthma ages 5 to 12 years. A total of 268 children completed this study according to the protocol, having received either metaproterenol or placebo for 30 consecutive days. Full spirometric testing was done pre- and postdose on Days 1 and 30 for a total duration of 6 hours on each day. The results showed that metaproterenol was consistently superior to placebo in all pulmonary function parameters measured on Days 1 and 30. This difference was statistically significant for peak values and areas under the curves for both FEV1 and FEF25-75%. There were no significant side effects noted. We conclude that metaproterenol metered dose inhaler is safe and effective in the treatment of asthma in children ages 5 to 12 years.  相似文献   
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