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31.
In 1942, Jaffe and Lichtenstein introduced the term aneurysmal bone cyst (ABC). Primary ABC is characterized by the presence of spongy or multi-cameral cystic tissue filled with blood. The process is benign, but it is locally destructive and has a high propensity for recurrence. In this paper, we present the third case of multiple metachronous primary ABCs as a rare variant of ABC. We describe the 10-year history of a 12-year-old boy with metachronous multiple primary ABCs at five different sites (right proximal humerus, right ulna, bilateral distal radius and right lateral clavicle). Furthermore, our patient suffered from vascular malformations, such as aortic isthmus stenosis, hypoplastic thoraco-abdominal aorta and bilateral renal artery stenosis. To date, in contrast to solitary ABC, the multiple lesions have been found more frequently in male individuals. Using interphase cytogenetics, we analyzed three of five of the patients ABCs and one of these was also analyzed by GTG-banding. No chromosomal abnormalities were found. Significantly, we excluded the missense mutation of codon 201 in guanine nucleotide-binding protein 1 gene consistently found in McCune-Albright syndrome (MAS) and in non-MAS cases of polyostotic fibrous dysplasia of bone with or without secondary ABC.  相似文献   
32.
This study examined alcohol use among seventh graders in relation to life events, daily hassles, the supportive quality of the family environment, coping, and anxiety. Four hundred twenty-five students participated, 228 girls and 197 boys. Stepwise regression and discriminant function analyses indicated that the students reported more alcohol use if they also reported more life events, more daily hassles, and more conflict in the family. A stress-buffering effect of low family conflict on life events could not be substantiated for extent of alcohol use. The results are discussed in the context of the developmental transitions of adolescence.  相似文献   
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BACKGROUND: A variety of evidence suggests that frontostriatal dysfunction is involved in obsessive-compulsive disorder (OCD). This evidence includes both neuroimaging findings and results from studies using neuropsychological assessments. Previous studies have documented nonverbal memory deficits in individuals with OCD, whereas verbal learning and memory were less affected. METHODS: The present study examined both verbal and nonverbal memory in a sample of 17 untreated outpatients with OCD. We also evaluated the effects of encoding strategies which are believed to be mediated by frontostriatal system functioning. RESULTS: OCD patients were significantly impaired in both verbal and nonverbal memory performance. This deficit was correlated with impairments in organizational and semantic clustering strategies at the time of encoding. CONCLUSIONS: Deficits in organizational strategies are consistent with frontostriatal dysfunction models in OCD.  相似文献   
35.
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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One important application of DNA microarray technology is the simultaneous analysis of gene expression of different mRNAs. Comparison of mRNA patterns of diseased and healthy tissue may help to understand the pathogenesis of a given disorder. In cancer tissue, identified dysregulated genes may serve as new molecular markers for diagnosis or prognosis or may ideally serve as new targets for therapy. Using membrane cDNA array technology, we analyzed gene expression in human melanomas, one of the most aggressive types of cancer with a high metastatic potential and with markedly increased incidence worldwide. To account for the heterogeneity of tumors, we compared total RNA from cutaneous melanoma metastases of 10 different patients with primary human melanocytes. An abundance of genes was dysregulated (up-/downregulated), which involved for example the apoptosis gene growth factor receptor-bound protein 10, Bcl2-associated X membrane protein, Bcl2 antagonist of cell death, glutathione S-transferase theta(1) and glutathione reductase. Ultimately, the identification of melanoma-associated genes may provide a potential therapeutic strategy for identifying and targeting malignant melanoma.  相似文献   
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An outbreak of hepatitis A occurred in a rural elementary school in Colbert County, Alabama, in October and November 1972. The outbreak was caused by sewage-contaminated drinking water and involved 49 children and 1 adult. Acute and convalescent serum samples were obtained from the hepatitis patients, and from each of 24 unafflicted matched controls at the same time. Strinkingly, the levels of the third and fourth components of complement (C'3 and C'4) were markedly reduced in the acute samples from the sick children but returned to normal in the convalescent ones; the C'3 and C'4 levels in the healthy matched controls were not reduced. In addition, antigen-antibody complexes were found in convalescent sera from some of the sick children. These findings indicate that immune complexes are present in acture hepatitis A and suggest that the techniques for future virus isolation may have to be altered.  相似文献   
40.
Previous studies have suggested that human follicular fluid contains factors that reduce the zona-binding capacity of spermatozoa. The present study provides further evidence of the existence of such factors. Using the hemizona binding assay (HZA), we have shown that the inhibitory effect of human follicular fluid on the zona-binding capacity of spermatozoa is concentration-dependent, an inhibitory effect being detected when the concentration of human follicular fluid was > or = 10%. A 1% concentration of human follicular fluid did not possess this inhibitory activity. Heating human follicular fluid at 56 degrees C for 30 min did not affect its inhibitory properties; treatment with proteinase-K abolished such inhibition. Human follicular fluid was fractionated sequentially by concanavalin-A affinity chromatography, Mono Q ion-exchange chromatography and Superose-12 gel filtration. The zona binding inhibitory activity resided in the fraction which bound to the lectin and Mono Q column and contained molecules with native molecular weights of 32 and 192 kDa. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis analysis suggested that the 192 kDa glycoprotein was a tetramer, while the 32 kDa glycoprotein remained as a single molecular species under denaturing conditions. We conclude that two glycoproteins were responsible for the zona binding inhibitory activity of human follicular fluid. The physiological role of these factors remains unclear.   相似文献   
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