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61.
The brain represents the primary centre for the regulation and control of all our body activities, receiving and interpreting sensory impulses and transmitting information to the periphery. Most importantly, it is also the seat of consciousness, thought, emotion and especially memory, being in fact able to encode, store and recall any information. Memory is really what makes possible so many of our complex cognitive functions, including communication and learning, and surely without memory, life would lose all of its glamour and purpose. Age-associated mental impairment can range in severity from forgetfulness at the border with pathology to dementia, such as in Alzheimer's disease. In recent years, one of the most relevant observations of research on brain aging relates to data indicating that age-related cognitive decline is not only due to neuronal loss, as previously thought; instead, scientists now believe that age-associated functional changes have more to do with the dysfunctions occurring over time. Within this context a prominent role is certainly played by signal transduction cascades which guarantee neuronal cell to elaborate coordinated responses to the multiple signals coming from the outside and to adapt itself to the environmental changes and requests. This review will focus the attention on protein kinase C pathway, with a particular interest on its activation process, and on the role of protein-lipid and protein-protein interactions to selectively localize the cellular responses. Furthermore, information is emerging and will be discussed on the possibility of mRNA stabilization through PKC activation. This review will also approach the issue on how alterations of these molecular cascades may have implications in physiological and pathological brain aging, such as Alzheimer's disease.  相似文献   
62.
以钒基核苷酸复合物为核酸酶抑制剂,从人胚组织中制备总RNA,所得产品几乎不含DNA和蛋白质,经过分离Poly(A)~ mRNA,证明制品有合成cDNA的完整功能,方法比较简捷,适于大量制备以满足分离mRNA 之需,并讨论了此法的优缺点。  相似文献   
63.
腹腔镜肝右后叶囊肿开窗引流术35例报告   总被引:6,自引:1,他引:5  
目的:探讨肝右后叶肝囊肿的腹腔镜处理方法。方法:1998年1月~2005年12月对35例有症状的肝右后叶囊肿(21例主要位于Ⅵ段,14例主要位于第Ⅶ段)采用四孔法行囊肿开窗引流术。囊肿位于肝右后叶上段者采用肝上入路,胆囊牵引钳或三叶钳推压肝脏使其向前向下,暴露肝后囊肿,囊肿开窗,修剪带蒂大网膜放入囊肿。囊肿位于肝右后叶下段者采用肝下入路,超声刀切开肝结肠韧带,右三角韧带及肝肾间疏松组织,胆囊牵引钳抬起肝脏,囊肿开窗,大网膜放入囊腔引流。结果:35例肝右后叶肝囊肿均在腹腔镜下完成肝囊肿开窗引流术,无中转开腹手术。15例采用肝上入路,20例采用肝下入路。手术时间30~95min,平均46min。无手术并发症。35例病理检查结果均为先天性肝囊肿。术后症状均消失。术后住院2~5d,平均3.8d。35例随访6~36个月,平均34个月,33例无复发,2例(为肝上入路病例)囊肿未完全消失,但较术前明显缩小,无明显症状,观察半年未见增大。结论:肝下及肝上入路囊肿开窗引流是腹腔镜下处理肝右叶肝囊肿的有效方法。  相似文献   
64.
Pathophysiological aspects of brain edema   总被引:16,自引:0,他引:16  
Summary Two mayor types of brain edema, related to two different pathomechanisms, can be recognized: 1)cytotoxic type-where the main feature is the swelling of cellular elements of brain parenchyma and 2)vasogenic type-where an increased vascular permeability leading to accumulation of edema fluid inthe extracellular spaces plays the principal role. In this type of edema, there is a close interrelationship between extravasation of serum proteins and retention of water in the brain tissue. In theischemic brain edema both cytotoxic and vasogenic mechanisms are involved. A biphasic opening of the blood-brain barrier, associated with vasogenic edema, is observed following release of major cerebral artery occlusion. The first opening of the barrier is related to a reactive hyperemia which follows promptly recirculation. The second opening, recognizable after a delay, is associated with a severe ischemic brain tissue injury.Dedicated to Prof. F. Seitelberger on the occasion of his seventieth birthday  相似文献   
65.
66.
头颈部肿瘤放疗后会引起不同程度的甲状腺功能减退.引起甲状腺功能减退的机制包括射线对甲状腺及垂体细胞的直接损伤、对相关血管的损伤以及自身免疫反应等.影响头颈部肿瘤放疗后甲状腺功能的因素主要有:放疗剂量、放疗技术、是否联合手术化疗等.通过对这些影响因素的研究可为防治甲状腺功能减退提供依据,从而提高患者生活质量.  相似文献   
67.
新疆医科大学为全国第二家中西医合并院校.在新疆进行中西医合校,实属时势所使,事在必行.强弱相合,处于弱势的中医学院只有坚持相对独立,才能保证于合校后发扬中医药特色、办好中医药教育.中西医合校,给原本弱小的新疆高等中医药教育事业的发展带来了诸多可供凭借和利用的积极因素,同时也存在不少负面影响.新疆医科大学在实践中认清了中西医同校的优势与缺憾,采取扶持和爱护中医的策略,不断尝试规避冲突、化解矛盾、趋利祛弊、务期和谐,终喜事业有成,使高等中医药教育得以在新疆生存,并越过低谷,走上健康发展之路.  相似文献   
68.
急诊抗菌药物的使用调查与分析   总被引:1,自引:0,他引:1  
目的考察了解急诊抗菌药物的使用情况。方法随机抽取2008年7—12月的急诊处方2700张,对其中抗菌药物的应用情况进行统计分析。结果急诊抗菌药物使用率49.1%,药物应用形式以单用为主(占66.3%);给药途径以口服和静脉注射为主。不合理用药处方占抗菌药物处方的10.8%,分别在选药方案、给药方案、溶媒使用、联合应用等方面存在问题。结论我院急诊抗菌药物的应用基本合理,但仍存在一定问题,需进一步加强管理。  相似文献   
69.
70.
Summary We prospectively examined bone growth patterns in 894 children aged 6–17 years at the baseline visit, with a 6-year follow-up. Results show bone “tracking” over a six-year interval and sexual dimorphism of bone attained levels and timing of peak bone growth. Our findings underscore childhood and adolescence as critical periods for building bone and developing gender differences. Introduction Bone growth patterns were prospectively examined in 894 Chinese children (496 males), aged 6–17 yrs, from a population-based twin cohort. Whole-body bone area (BA), bone mineral content (BMC), and bone mineral density (BMD) were measured by DEXA at baseline and a 6-yr follow-up. Methods Graphic smoothing plots and generalized estimating equations were used to model bone attained levels, growth, and “tracking”. Results Attained levels of BMC and BA increased curvilinearly with age. Male attained levels were higher than females after age ∼15 yr, but BMD was lower between 13–17 yrs (Tanner stage I to IV). In both genders, peak BMC and BMD growth lagged ∼2 yrs behind peak BA growth, which lagged 2 yrs behind peak height growth. Peak bone growth occurred 1–3 yrs later in males. Over the 6-yr follow-up, all bone measurements “tracked”, but “shifting” across ranks also occurred, and baseline tertile ranking influenced bone growth. Females with early menarche had higher attained levels than females with late menarche at age 12–13 yrs. Conclusion Our findings confirm and expand previous studies on peak bone growth conducted in Caucasian cohorts, particularly sexually dimorphic and maturational effects. The significant “tracking” of bone measurements in this 6-yr follow-up study underscores the importance that osteoporosis prevention should begin in childhood and adolescence. Fengxiu Ouyang and Binyan Wang contributed equally to this article. Source(s) of support: This study is supported in part by grant R01 HD049059, R01 HL0864619 and R01 AR045651 from the National Institute of Health and by the Food Allergy Project.  相似文献   
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