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Primary tuberculous pathology in nasolpolypi is a rare condition. A case of bilateral ethmoidal polypi with tubercular lesion diagnosed on histopathologlcal examination is being reported and the available relevant literature has been reviewed.  相似文献   
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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   
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目的:对临床确诊糖尿病患同时测定血清葡萄糖(Glu)及糖化血清蛋白(GSP)的含量,观察二的关系,以及糖化血清蛋白水平对于评价近期(2—3周)糖尿病患血糖在体内变化的临床意义进行了观察。方法:血清葡萄糖、糖化血清蛋白测定均采用酶法测定。结果:178例糖尿病患Glu、GSP均正常3l例占17.4%;Glu、GSP均增高107例占60.1%;Glu正常、GSP增高15例占8.43%;Glu增高、GSP正常25例占14%。结论:糖化血清蛋白的含量不受即时血糖的影响,二的变化不成比例性,对评价糖尿病患2~3周病情的控制是一项灵敏可靠的指标,尤其对于住院病人的治疗与监控有一定的意义。  相似文献   
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While attrition from sharp bony surfaces is the most common cause of extensor digiti minimi (EDM) tendon rupture, the etiology of other cases of spontaneous EDM tendon rupture is still unknown. Friction within the compartment may play a role, especially with ulna dislocation. The purpose of this study was to compare gliding resistance of the EDM tendon with that of a tendon which rarely ruptures spontaneously, the extensor digitorum communis of the middle finger (EDC III) tendon, under various wrist and ulna head positions. Eight fresh frozen cadavers were used. Gliding resistance between the tendon and its sheath in each compartment was measured in five different wrist positions and three different ulna head positions. Gliding resistance of the EDM tendon (0.13 +/- 0.03 N) was significantly greater than the EDC III tendon (0.09 +/- 0.03 N) (p < 0.05). For the EDM tendon, the gliding resistance in ulnar deviation or pronation was higher than the gliding resistance in neutral, radial deviation, or supination (p < 0.05), and the gliding resistance with ulnar lengthening (over 6 mm) or dorsal ulnar dislocation (over 9 mm) was higher than in neutral ulnar head positioning. For the EDC III tendon, the gliding resistance in ulnar deviation was significantly higher than the gliding resistance in neutral, radial deviation, or supination, or dorsal dislocation with ulnar lengthening (p < 0.05). Wrist ulnar deviation, ulnar dorsal dislocation (over 9 mm), and ulnar lengthening (over 6 mm) increased the gliding resistance of the EDM tendon. In patients at risk for EDM rupture, such as those with rheumatoid arthritis or distal radioulnar joint osteoarthritis, avoiding such positions may be advantageous.  相似文献   
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Steroid 21-hydroxylase deficiency is among the most common inborn errors of metabolism in man. Characterization of mutations in the 21- hydroxylase gene (CYP21) has permitted genetic diagnosis, facilitated by the polymerase chain reaction (PCR). The most common mutation is conversion of an A or C at nt656 to a G in the second intron causing aberrant splicing of mRNA. Homozygosity for nt656G is associated with profoundly deficient adrenal cortisol and aldosterone synthesis, secondary hypersecretion of adrenal androgens, and a severe form of congenital adrenal hyperplasia (CAH) characterized by ambiguous genitalia and/or sodium wasting in newborns. During the course of genetic analysis of CYP21 mutations in CAH families, we and others have noticed a number of relatives genotyped as nt656G homozygotes, yet showing no clinical signs of disease. A number of lines of evidence have led us to propose that the putative asymptomatic nt656G/G individuals are incorrectly typed due to dropout of one haplotype during PCR amplification of CYP21. For prenatal diagnosis, we recommend that microsatellite typing be used as a supplement to CYP21 genotyping in order to resolve ambiguities at nt656.   相似文献   
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