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71.
IG Gazaryan IV Ouporov TA Chubar VA Fechina EA Mareeva LM Lagrimini 《Canadian Metallurgical Quarterly》1998,63(5):600-606
The dendritic localization of mRNAs has been proposed to underlie the structural and functional polarity of neurons, as well as certain aspects of synaptic plasticity. Even though there is no conclusive evidence that such a localization is a physiological requirement, studies of mRNA localization in relation to function in other cell types and recent experiments on synaptic plasticity suggest that this proposal may be correct. 相似文献
72.
IV Pavlova 《Canadian Metallurgical Quarterly》1998,48(3):396-404
We have investigated whether hypoxia and muscle contractions stimulate glucose transport in perfused rat muscle to the same extent, additively and with the same sensitivity to the microbial products calphostin C and wortmannin. Hindlimb glucose uptake increased gradually from 3.4+/-0.5 to a maximal level of 12.7+/-0.6 micromol g-1 h-1 (n=11) after 50 min of hypoxia. Compared with hypoxia, the effect of maximal electrical stimulation of the sciatic nerve on muscle glucose uptake was more than two-fold higher (27+/-2 micromol g-1 h-1 (n=14)). This was due to a higher contraction- vs. hypoxia-induced glucose transport rate in oxidative fibers. The stimulatory effect of hypoxia and electrical stimulation was not additive. Contraction-induced muscle glucose transport was inhibitable by both calphostin C and wortmannin in the micromolar range, whereas the effect of hypoxia was totally insensitive to these drugs. Our data suggest that diacylglycerol/phorbol ester-sensitive protein kinase C is involved in stimulation of muscle glucose transport by contractions and that in contrast to the prevailing concept, hypoxia and contractions do not stimulate muscle glucose transport by the same signaling mechanism. 相似文献
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In the 14, 3 and 90 day-experiments with tail-suspended rats, histochemical determination of myosin ATP-ase activity in m. soleus and m. gastrocnemius preincubated in acid and neutral media was followed by measurement of the cross-sectional areas (CSAs) of muscular fibers (MF) and calculation of the percentage of various types of MF. By day 30 of testing atrophy in m. soleus reached maximum and stabilized. By that time, MF CSAs were less than in the control by 69, 62, and 68% in MF-I, -IIA and -IIC, respectively. Slow MF underwent the transformation into fast and intermediate. In slow MF this process peaked by day 3 when the number of these fibers decreased by 28% as compared to the control, and stabilized. The transformation of intermediate fibers into the fast ones was progressing simultaneously. This process was not finished by day 90. Atrophy of m. gastrocnemius was less pronounced than in m. soleus. On day 14 of experiment, MF CSAs, except for IIB, were by 30% smaller than in the control. Type IIB MF were less affected as their CSAs decreased by only 17% as compared with the control. On day 90, CSAs in both slow and IIC-type fast MFs remained approximately same as in the rats investigated on day 14. Fast MF CSAs either tended to (IIA) or regained (IIB) the norm. Hence, atrophy in m. gastrocnemius stabilized earlier than in m. soleus. Besides, longer suspension led to a partial or complete reconstruction of two out of three types of fast fibers. The percent ratio of MFs was unchanged; however, during the ATP-ase determination slow IB-type MFs assumed th color typical of fast MFs. 相似文献
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IuI Vorob'ev MI Garbuzov IV Limarova AI Pechurchik LA Sulaeva 《Canadian Metallurgical Quarterly》1995,74(4):26-28
Results of three-year radiotherapy are assessed in 586 patients with skin cancer, with tumors localized on the skin of the face in 484 of these. The results of treatment were found to depend on the histological structure of the tumor and disease stage: 100% cure was attained in patients with basal-cell carcinomas and T1 stage, whereas only 7% of patients with T4 stage were cured; in patients with squamous-cell carcinoma these figures were, respectively, 96.2 and 10%. 相似文献
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IV Design Associates Inc. 《建筑技艺》2007,(6)
建于上世纪60年代的波希米亚官邸,位于皇后西街,这里曾是一间充满着传奇色彩的咖啡屋,也是当时多伦多民歌文化和爵士文化一个非常重要的聚会地点. 相似文献
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