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101.
Jackstone calculi are urinary tract stones that have a specific appearance resembling toy jacks. They are almost always composed of calcium oxalate dihydrate and may be found in the urinary bladder or rarely in the upper urinary tract. Their appearance on plain radiographs and computed tomography (CT) in human patients has been well described. They have also been imaged in several species of animals. However, our review of the English medical literature revealed no previous report in which a jackstone calculus had been identified on the sonographic examination of a human patient. We report a case in which a large jackstone calculus was incidentally detected during abdominal sonography in a 75-year-old man.  相似文献   
102.
TRACP, a marker of osteoclasts, is also expressed by cells of the immune system. We identified a novel function for TRACP in the dendritic cell. DCs from TRACP knockout mice have impaired maturation and trigger reduced Th1 responses in vivo. We postulate that TRACP has an important role in the presentation of antigens to T cells. INTRODUCTION: TRACP is highly expressed by osteoclasts, activated macrophages, and dendritic cells (DCs). Knockout mice lacking TRACP have an intrinsic defect in osteoclastic resorption and macrophages that display abnormal immunomodulatory responses and cytokine secretion profiles. Our aim in this study was to investigate the significance of TRACP in the inductive phase of the immune response by examining dendritic cells from TRACP(-/-) mice. MATERIALS AND METHODS: Maturational state and function of leukocyte subsets in mice was assessed by flow cytometry. The ability of the immune system to respond to nonspecific activation and to specific antigen was assessed by delayed type hypersensitivity and the presence of isotype-specific serum antibody in vivo and T-cell proliferation and cytokine production in vitro. RESULTS: The ability of lipopolysaccharide (LPS) to upregulate MHC II and CD80 in DCs from TRACP(-/-) mice was reduced compared with wildtype mice, although production of IL-10 by DCs from TRACP-deficient animals was increased. T- and B-cell responses not involving antigen presentation (anti-CD3, TNP-ficoll) were normal in TRACP(-/-) mice, but responses to T-dependent antigens were impaired. Specifically, TRACP(-/-) mice had defective delayed hypersensitivity responses to picryl chloride and reduced proliferative responses to ovalbumin compared with wildtype mice. In response to ovalbumin, but not anti-CD3, T cells from TRACP(-/-) mice produced less interferon-gamma (IFN-gamma), but there was no difference in IL-4 production: TRACP(-/-) mice also produced less ovalbumin (OVA)-specific IgG2a after immunization. CONCLUSIONS: The finding that DCs from TRACP(-/-) mice have impaired maturation and defective Th1 responses shows that TRACP is important for polarizing responses in na?ve T cells to antigen-presented dendritic cells.  相似文献   
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104.
Previous studies on the metabolism of capsaicinoids, natural products isolated from chili peppers, demonstrated the production of unique macrocyclic, alkyl dehydrogenated, omega-, and omega-1-hydroxylated products. This study investigated the structural and enzymatic parameters that direct selective alkyl dehydrogenation and hydroxylation of capsaicinoids, using a variety of structurally related capsaicinoid analogs and cytochrome P450 (P450) enzymes. CYP2C9 preferentially catalyzed alkyl dehydrogenation, whereas CYP2E1 and 3A4 catalyzed omega- and omega-1-hydroxylation, respectively. Analysis of incubations containing various P450s and structural variants of capsaicin by liquid chromatography-tandem mass spectrometry demonstrated similarities in the rate of capsaicinoid metabolism, but marked differences in the metabolite profiles. Production of macrocyclic and omega-1-hydroxylated metabolites from the various capsaicinoids was dependent on the structure of the alkyl terminus and P450 enzyme. A tertiary carbon at the omega-1 position, coupled to an adjacent unsaturated bond at the omega-2,3 position, enhanced the formation of the macrocyclic and dehydrogenated metabolites and were requisite structural features for omega-1-hydroxylated product formation. Conversely, substrates lacking these structural features were efficiently oxidized to the omega-hydroxylated metabolite. These data were consistent with our hypothesis that metabolism of the alkyl portion of capsaicinoids was governed, in part, by the stability and propensity to form an intermediate radical and a carbocation, and a direct interaction between the alkyl terminus and the heme of many P450 enzymes. These results provided valuable insights into potential mechanisms by which P450s metabolize capsaicinoids and highlight critical chemical features that may also govern the metabolism of structurally related compounds including fatty acids, monoter-penes, and isoprenoids.  相似文献   
105.
PURPOSE: To evaluate rates, predictors, and barriers to use of the Internet to obtain cancer information among a cohort of cancer patients at an urban county hospital. PATIENTS AND METHODS: Of 208 cancer patients approached, 200 patients completed a structured interview study examining Internet use, perceptions of the accuracy of Internet information, and barriers to use. RESULTS: Only 10% of participants reported using the Internet themselves to obtain cancer information. Another 21% reported exposure to Internet information through proxies. The most common barrier to Internet use cited was lack of Internet access, with 44% reporting that they would use the Internet to obtain cancer information if they had Internet access. Younger age and more years of formal education were significantly associated with Internet use, although race and income were not. Less education, African American race, and female sex were associated with lower estimates of the accuracy of Internet information. Fewer years of formal education was associated with increased likelihood of reporting confusion after reading Internet information. CONCLUSION: Very few cancer patients in this study of a cohort of generally disadvantaged individuals used the Internet themselves to obtain cancer information, although many more desired to do so. Significant opportunities for Web-based interventions aimed at improving cancer care outcomes in this population of cancer patients exist. However, further study will be needed to determine how to make such intervention accessible, trustworthy, and understandable to the disadvantaged.  相似文献   
106.
Fifty-six children with and forty-five children without deficits in attention, motor control and perception (DAMP) had been recruited from the general population at age 7 years. They were followed up neuropsychiatrically at age 16 years after intermediate term follow up at age 10 and 13 years. Cases were subdivided into those with good and not good outcome on the basis of absence or presence of psychiatric and personality disorders, multiple traumatic accidents and speech and language problems at age 16 years. The presence of DAMP in itself was the strongest predictor of poor outcome. High scores for minor neurological dysfunction, low performance IQ, autistic features at age 7 years and poor reading skills at age 10 and/or 13 years were important background factors in cases with poor outcome. In the small subgroup with poor outcome among those without DAMP at age 7 years, major life events was the most important background factor.
Zusammenfassung 56 Kinder mit und 45 Kinder ohne Störungen der Aufmerksamkeit, der motorischen Kontrolle und der Wahrnehmung (DAMP) waren aus einer Gesamtpopulation 7jÄhriger rekrutiert worden. Sie wurden neuropsychiatrisch im Alter von 16 jahren nachuntersucht, nachdem zwischenzeitliche Untersuchungen im Alter von 10 und 13 Jahren erfolgt waren. Die Probanden wurden in solche mit gutem und nicht gutem Ausgang unterteilt, in AbhÄngigkeit vom Vorliegen psychiatrischer AuffÄlligkeiten, Persönlichkeitsstörungen, multiplen Traumata und Sprech- und Sprachproblemen im Alter von 16 Jahren. Das Vorhandensein von DAMP war der stÄrkste PrÄdiktor für einen schlechten Ausgang. Hohe Werte für leichte neurologische AuffÄlligkeiten, ein niedriger Handlungs-IQ, autistische Züge im Alter von 7 Jahren und schlechte LesefÄhigkeiten im Alter von 10 und/oder 13 Jahren waren wichtige Hintergrundfaktoren bei den Probanden mit einem schlechten Ausgang. In der kleinen Untergruppe mit einem schlechten Ausgang bei den Kindern, die im Alter von 7 Jahren kein DAMP ausgewiesen hatten, bildeten schwerwiegende Lebensereignisse den wichtigsten Hintergrundfaktor.

Résumé Cinquante-six enfants atteints et quarante-cinq enfants non atteints de déficits de l'attention, du contrÔle moteur et de la perception (DAMP), ont été recrutés en population générale à l'âge de 7 ans. Ils ont été évalués sur la plan neuropsychiatrique à l'âge de 16 ans, après des évaluations intermédiaires à l'âge de 10 et 13 ans. Les cas ont été subdivisés entre bons et mauvais devenir sur la base de la présence ou de l'absence de troubles de la personnalité, l'importance du nombre d'accidents traumatiques, les difficultés d'élocution et de langage à 16 ans. La présence de DAMP était en soi, le facteur prédictif le plus important de mauvais devenir. Des scores élevés à des dysfonctionnements neurologiques mineurs, un QI bas, des traits autistiques à l'âge de 7 ans, et de mauvaises capacités en lecture à l'âge de 10 ou 13 ans ont été des facteurs importants dans les cas de mauvais devenir. Dans le petit sous-groupe à mauvais devenir caractérisé par une absence de DAMP à l'âge de 7 ans, des événements de vie marquants ont semblé Être des antécédents importants.
  相似文献   
107.
108.
This paper examines two approaches for the analysis of quantitative traits: (1) association studies and (2) linkage studies. The trait studied was Q1 from simulated Problem 2 data set in Genetic Analysis Workshop 9. Our purpose was to evaluate associations present in the data, to identify nongenetic and genetic predictors of the trait, and to explore the simulated genome for linkage. Through the association study, we found evidence for the primary major gene associated with this trait. The linkage study found evidence of residual genetic effect acting through other traits. Adjustments of Q1 for Q2 and Q3 led to a failure to find significant effects of MG2 and MG3. This supports the suggestion that adjustment for genetically influenced traits for effects of other genetic traits can reduce the power to detect major gene effects. In summary, we detected the major gene directly associated with the trait of interest through association studies. Linkage analysis detected evidence for two other genes associated to a lesser degree with the trait. © 1995 Wiley-Liss, Inc.  相似文献   
109.
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