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A method of electrostimulation aimed at activation of bone adhesion processes was developed and introduced into practice at the Latvian Research Institute of Traumatology and Orthopedics on the basis of data on bone bioelectric activity. The method was used in complex with external fixation of the fracture by Kalnbers' apparatus. The phase pattern of callus formation necessitated the employment of the appropriate potential of direct current. Cyclic potentials similar to piezopotentials of a normal bone in cyclic physiological load were used in the phase of functional reorganization. Positive results were achieved in 88.4% of 79 patients.  相似文献   
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石杉碱甲(1)是从中草药石杉属植物千层塔(Lycopodium serratum Thunb.)中分得的一种高效可逆的乙酰胆碱酯酶抑制剂,临床试验证实它对早老性痴呆症有显著疗效。本文报道N-甲基吡啶酮石杉碱甲类似物2和3的合成。2-甲氧基-5-甲氧羰基-11-亚甲基-5,9-甲撑环辛-7-烯并吡啶(9)在乙腈中用三甲基氯硅烷和碘化钠选择性脱保护以定量的产率得吡啶酮10,再用甲醇钠和碘甲烷甲基化得N-甲基吡啶酮11,11经碱性水解,Curtius重排和氨基的脱保护得N-甲基吡啶酮石杉碱甲类似物2。通过类似的途径从中间体2-甲氧基-5-甲氧羰基-7-甲基-11-酮-5,9-甲撑环辛-7-烯并吡啶(14)合成了类似物3。类似物2和3的乙酰胆碱酯酶抑制活性均低于天然石杉碱甲。  相似文献   
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脑干是生命中枢所在部位,也是神经中枢的“中枢””’,该部位肿瘤手术风险大,治疗效果差。随着显微外科和影像学等技术的发展,现在脑干肿瘤手术取得很大的进展。如何在尽可能切除脑干肿瘤的同时,及时察觉和避免损伤正常脑干组织,使手术更加安全,除了应用显微外科等...  相似文献   
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INTRODUCTION: Aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs) have been shown to reduce risk of colorectal cancer. Although inhibition of cyclooxygenase (COX)-2 is generally thought to be the relevant mechanism, aspirin-like drugs apparently are involved in other pathways and mechanisms. We explore the associations between aspirin/NSAIDs, the insulin-related pathway, and the risk of colorectal cancer. METHODS: Genetic polymorphisms of five genes identified as being involved in an insulin-related pathway were genotyped using data collected in a case-control study of 1346 incident colon cancer cases and 1544 population-based controls and 952 incident rectal cancer cases and 1205 controls. Genotypes assessed were the 3' untranslated region poly(A) and the intron 8 BsmI polymorphisms of the VDR gene, a CA repeat polymorphism of the IGF1 gene, the A/C polymorphism at nucleotide -202 of the IGFBP3, the Gly972Arg polymorphism of the IRS1 gene, and the Gly1057Asp polymorphism of the IRS2 gene. RESULTS: Use of aspirin and NSAIDs was associated with a decreased risk of colorectal cancer, with slightly greater protection from NSAIDs than aspirin for rectal cancer. We observed a significant interaction between IRS1 genotype and aspirin/NSAIDs use and risk of colorectal cancer. Relative to the GR/RR IRS1 genotype, a protective effect from the GG IRS1 genotype was seen in those who did not use NSAIDs; use of NSAIDs was protective for all genotypes. These associations were especially strong for those diagnosed prior to age 65 (P interaction = 0.0006). We also observed a significant interaction between aspirin/NSAIDs use and the VDR gene. Having the SS or BB VDR genotypes reduced risk of colorectal cancer among non-aspirin/NSAID users; however, aspirin/NSAIDs reduced risk for all VDR genotypes. CONCLUSIONS: These data support the protective effect of aspirin and NSAIDs on colorectal cancer risk. In addition, the observed interactions for aspirin/NSAIDs and IRS1 and VDR genotypes suggest that mechanisms other than COX-2 inhibition may be contributing to the protective effect of aspirin and NSAIDs on colorectal cancer risk.  相似文献   
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The present study focuses on expanding and broadening the connection between meaning in life and psychoactive substance abuse. Since professional literature presents an individual’s meaning in life as an immunizing factor against substance abuse, the present study sought to examine the impact of level of religiosity and level of ideological-political commitment, through the prism of meaning in life, on the attitudes adopted by adolescents towards such abuse, and their actual use of the various substances. The findings of the study, in which 1032 Israeli adolescents aged 14 to 18 took part, supported the hypothesis whereby a high level of religiosity “immunizes” against psychoactive substance abuse. However, they also indicate that despite the negative approach to it among individuals with high levels of ideological commitment, no significant correlation can be found between ideological commitment and actual psychoactive substance abuse. The study findings underscore the importance of both religion and ideological commitment in the formation of meaning in life by youth, as well as the impact of social supervision and perceived norms in their environment, with regard to their willingness to attempt using psychoactive substances, and their actual use thereof. The study findings contribute both to research and practical application when constructing programs for the prevention of normative adolescent substance abuse.  相似文献   
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Neuro-Pathology     
Behçet's disease (BD) is a type of vasculitis with a chronic relapsing course that affects arteries and veins of all sizes. Intracranial aneurysms are rare manifestations. We report a patient with the diagnosis of BD, who had a fusiform aneurysm of the internal carotid artery at the level of the sinus cavernosus. He presented with sinus cavernosus syndrome findings. The aneurysm was treated endovascularly.  相似文献   
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