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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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Previous reports describe a characteristic, rapidly progressive, periodontitis that is unique to patients who are seropositive for HIV antibody (Western blot +). The purpose of this study was to compare the T4 and T8 lymphocyte subpopulations in the peripheral blood and periodontal lesions of these HIV patients with those of healthy controls. T-cell subsets in peripheral blood were quantified by flow cytometry. The values from this analysis were used to calculate the peripheral T4:T8 lymphocyte ratio for each patient. Gingival tissue (papilla) was obtained from 8 HIV+ patients and from 6 healthy HIV- control patients during routine gingival surgery. The T-cell subpopulations in the gingival tissue were determined using serial cryostat sections that were labeled with monoclonal antibodies for T4 and T8 cells and developed using an avidin-biotin-peroxidase system. Six sections were taken from each of the 14 tissue specimens (one per patient). The sections were examined at 450 x and the mean number of T4 and T8 cells calculated for each section. These mean values were then used to determine the T4:T8 lymphocyte ratio for each tissue specimen. The peripheral blood analysis revealed a mean serum T4:T8 ratio of (2.07 +/- 0.455) for the controls and (0.58 +/- 0.26) for the HIV patients. The significantly lower T4:T8 ratio in HIV patients is consistent with their diagnosis. Although the results indicated that the mean T4:T8 lymphocyte ratio in the gingiva of controls was highly variable (2.70 +/- 1.344), the gingiva of HIV patients consistently exhibited a complete absence of T-cells.(ABSTRACT TRUNCATED AT 250 WORDS)  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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Robert Kastenbaum posits that functional aging results in the overadaptation to our own routines and expectations, producing "hyperhabituation," mental stagnation, and novaphobic response orientations. This article examines the promise and implications of this notion for two areas of environment-aging research: psychological control and environmental comprehension. Possible causal and mediating links between control and habituation are considered, as well as the impact of habituation on environmental perception, cognition, and appraisal. Personal and situational characteristics of older people likely to be at risk for habituated responses are suggested. The article also speculates about individually- and environmentally-targeted interventions which might prevent and/or ameliorate tendencies toward hyperhabituated responses among older people who reside in highly ritualized and constant environments such as long-term care institutions. Interventions subject to future evaluations include modifications for the social, physical, and policy milieux and desensitization of novaphobic responses.  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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Tuberous sclerosis is an autosomal dominant trait in which the dysregulation of cellular proliferation and differentiation results in the development of hamartomatous growths in many organs. The TSC2 gene is one of two genes determining tuberous sclerosis. Inactivating germline mutations of TSC2 in patients with tuberous sclerosis and somatic loss of heterozygosity at the TSC2 locus in the associated hamartomas indicate that TSC2 functions as a tumour suppressor gene and that loss of function is critical to expression of the tuberous sclerosis phenotype. The TSC2 product, tuberin, has a region of homology with the GTPase activating protein rap1GAP and stimulates the GTPase activity of rap1a and rab5a in vitro. Here we show that the region of homology between tuberin and human rap1GAP and the murine GAP mSpa1 is more extensive than previously reported and spans approximately 160 amino acid residues encoded within exons 34-38 of the TSC2 gene. Single strand conformation polymorphism analysis of these exons in 173 unrelated patients with tuberous sclerosis and direct sequencing of variant conformers together with study of additional family members enabled characterisation of disease associated mutations in 14 cases. Missense mutations, which occurred in exons 36, 37 and 38 were identified in eight cases, four of whom shared the same recurrent change P1675L. Each of the five different missense mutations identified was shown to occur de novo in at least one sporadic case of tuberous sclerosis. The high proportion of missense mutations detected in the region of the TSC2 gene encoding the GAP-related domain supports its key role in the regulation of cellular growth.   相似文献   
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