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971.
Positron emission tomography was performed on six patients with Rett syndrome to investigate cerebral blood flow and oxygen metabolism, and the results were compared with the concurrent clinical status of the patients. The cerebral metabolic rate of oxygen (CMRO2) was low in five patients, and oxygen extraction fraction was low in four patients; both had a tendency to decline with advancing age. Although the cause is unknown, it is suggested that impaired oxidative metabolism exists in Rett syndrome. An analysis of the distribution among brain regions showed that the ratios of values for the frontal cortex to those for the temporal cortex for both cerebral blood flow and CMRO2 were lower than those for the controls, which may indicate the loss of hyperfrontality in Rett syndrome.  相似文献   
972.
973.
974.
975.
4-(1H-Benzimidazol-1-ylmethyl)-and 4-(2-methyl-1H-benzimidazol-1-ylmethyl)phenyl-β-D-glucopyranosides have been synthesized by glycosylation of the corresponding phenols. The hemolytic activity of the synthesized compounds was studied on whole venous human donor blood at concentrations of 100, 200, and 300 μg/mL. It was established that the glycosides exhibit high biological activity and enter erythrocytes faster than do the initial phenols, which suggests that they are promising for the development of new drugs. __________ Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 12, pp. 16–17, December, 2007.  相似文献   
976.
977.
The gamma-irradiation of adult rats with a semi-lethal dose (6 Gy) suppressed the posttraumatic regeneration of skeletal muscles and brought about considerable destructive changes in the thymus. The effect of He-Ne laser radiation at a total dose 4.5-5.4 J/cm2 at each operated leg in irradiated rats stimulated the regenerative capacity of skeletal muscle tissue, the healing of skin-muscle wound, and the processes of postradiation recovery in thymus cells (a decrease of chromosome aberrations). The histological structure of regenerates had more muscle pattern. At the same time, the positive dynamics of regenerative processes in muscles was achieved by an increased functional load on the thymus. To stimulate the regeneration of irradiated muscles on the background of a more moderate load on the thymus, the prolonged period of laser therapy and fragmentary distribution of laser exposures during muscle regeneration were preferable. Wound healing improved visibly. Nor formation of chronic radiation ulcers on operated shins was observed.  相似文献   
978.
979.
A case of radiologically occult lung cancer is presented in which 201TI SPECT of the chest clearly delineated the involved area. A 66-yr-old man underwent chest screening examinations for asymptomatic smokers and presented a positive sputum cytology for lung cancer. Conventional chest x-ray, tomography of computed radiography, and a CT scan failed to locate the lesion in the lung. Thallium-201 SPECT, however, was successful in depicting the area of the involvement.  相似文献   
980.
Neuroprotective activity with magnesium associated with animal models of cerebral ischaemia, seizure, perinatal hypoxia/ischaemia, subarachnoid haemorrhage and traumatic brain injury has provided the justification for clinical stroke trials. However, the recent IMAGES stroke clinical trial found magnesium to be largely ineffective. Hence, due to the negative stroke trial outcome, current FAST-MAG trial and our own experience with magnesium in cerebral ischaemia animal models, we thought it prudent to review these preclinical and clinical studies. We reviewed nine studies describing the use of magnesium following global cerebral ischaemia and fourteen following focal cerebral ischaemia. Four global ischaemia and six focal ischaemia studies did not show a significant neuroprotective effect with magnesium. In the majority of positive magnesium studies animal body temperature was not monitored post-ischaemia. Thus the effects of post-ischaemic hypothermia cannot be ruled out as a confounding factor in positive magnesium cerebral ischaemia studies. Moreover, data from our own laboratory indicates that magnesium is only neuroprotective when combined with post-ischaemic hypothermia. These data provide a possible explanation of why the IMAGES trial was largely unsuccessful, as current stroke patient management does not involve hypothermia induction. Future preclinical and clinical cerebral ischaemia trials with magnesium should consider combining treatment with mild hypothermia.  相似文献   
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