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961.
Salivary stones, or sialolithiasis, are calcifications found in the salivary ducts, less commonly in the parotid ducts and more frequently in the submandibular system. Parotid stones cause obstructions that result in parotid swellings, a decrease in salivary flow and secondary infection. The limited options for treatment of a parotid stone are varied, but include its surgical removal via dissection into the duct. The authors present a case of parotid sialolithiasis that was treated with surgical removal of the stone via an intraoral surgical approach.  相似文献   
962.
Pemphigus vulgaris (PV) is traditionally viewed as an autoimmune disease of the skin, but it almost always involves the oral cavity. It can be fatal if left untreated and allowed to progress to advanced stages. Early recognition and intervention are essential for a favorable prognosis. Since oral lesions represent an initial manifestation of PV, dentists are in an ideal position to make an early diagnosis and initiate treatment. Here we report a case of PV that was diagnosed in its earliest stage.  相似文献   
963.
A murine model of experimental silicosis has been developed after the intratracheal injection of alpha-quartz crystals. Pulmonary inflammation was monitored by increases in wet lung weight and cell number and protein content of the lung lavage fluid; fibrosis was assessed by measuring increases in hydroxyproline content of the lungs. Acute pulmonary cellular inflammation occurred between weeks 1 and 2, followed by a chronic inflammatory response at week 12. Lung hydroxyproline content, an indication of collagen deposition, was initiated as early as 1 week after silica injection and continued to increase steadily over time. The inflammatory and fibrotic changes induced by silica appeared to be a specific effect of the injection of this toxic particulate and not the result of the introduction of a foreign body, because mice injected with silica crystals were found to have significantly greater increases in acute cellular inflammation and chronic collagen deposition than did mice injected with latex beads. A possible role for the immune system in modulating silica-induced damage was suggested by the variability in response of six different strains of mice (C3H/He, CBA/J, Balb/c, DBA/2, C57BL/6, C57BL/10), which differed at specific genetic loci. Both strains with high (DBA/2) and low (C3H/He) response demonstrated similar patterns of inflammation and fibrosis over a period of 12 weeks. This model demonstrates great potential in future studies for elucidating the role of the immune system in the development of pulmonary inflammation and fibrosis induced by toxic inorganic particulates.  相似文献   
964.
965.
Binding of antibody to the surface of B lymphocytes was shown to involve the Fc piece of the immunoglobulin molecule. This property was not shared equally by all immunoglobulin classes as revealed by direct binding and inhibition studies. Total IgG globulin was found to label cells more heavily than IgM, and IgG1-containing fractions more heavily than IgG2 fractions lacking IgG1. The ability of various purified myeloma proteins to inhibit attachment of antibody to B cells was examined. Pretreatment of B cells with excess IgG2a, IgA, or light chain proteins failed to inhibit, whereas IgG1 proteins and to a lesser extent Ig2b and IgM proteins at the same concentrations did so. At lower protein concentrations, IgG1 myeloma protein alone retained the capacity to inhibit binding. The conclusion was reached that the receptor on B cells for antibody has a marked predilection for the IgG1 class. Although IgM and IgG2b antibody may bind, they do so with lower avidity and probably in insignificant amounts if IgG1 antibody is present in excess. No evidence was found to implicate complement in the binding process. For example, heat-inactivated sera at high dilution retained the ability to label B cells, while the use of purified low molecular weight anticomplementary factor, a potent inhibitor of C''3, did not interfere with the formation of the bond between antibody and cell surface. The failure of anti-mouse immunoglobulin F(ab)''2 fragments to prevent access of antibody to B cells implied that the antibody-binding receptor and antigen-binding (immunoglobulin) receptor are discrete entities on the B cell membrane. Despite this, a marked similarity between their surface distribution was observed on electron microscopy. The antibody-binding receptor was shown to be a marker for mature B cells. It did not appear to be present on hematopoietic precursor stem cells and was lost during differentiation to antibody-forming cells.  相似文献   
966.
Recombinant adeno-associated virus (rAAV) is derived from a small human parvovirus with an excellent safety profile. In addition, this viral vector efficiently transduces and supports long-term transgene expression in the nervous system. These properties make rAAV a reasonable candidate vector for treating neurological disorders. Indeed, rAAV is currently being used in five early stage clinical trials for various neurodegenerative disorders. Therefore, we will review the currently available preclinical data using rAAV in animal models of central nervous system (CNS) disorders. Moreover, potential caveats for rAAV-based gene therapy in the CNS are also presented.  相似文献   
967.
To inform risk assessment and regulatory decision-making, the relationship between 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and prostate cancer requires clarification. This article systematically and critically reviews the epidemiologic evidence on the association between exposure to TCDD or Agent Orange, a TCDD-contaminated herbicide used during the Vietnam War, and prostate cancer risk. Articles evaluated include 11 studies of three cohorts, four case–control or cross-sectional studies, and three case-only studies of military veterans with information on estimated Agent Orange or TCDD exposure; 13 studies of seven cohorts, one case–control study, and eight proportionate morbidity or mortality studies of Vietnam veterans without information on Agent Orange exposure; 11 cohort studies of workers with occupational exposure to TCDD; and two studies of one community cohort with environmental exposure to TCDD. The most informative studies, including those of Vietnam veterans involved in Agent Orange spraying or other handling, herbicide manufacturing or spraying workers with occupational TCDD exposure, and community members exposed to TCDD through an industrial accident, consistently reported no significant increase in prostate cancer incidence or mortality. Only some potentially confounded studies of Vietnam veterans compared with the general population, studies with unreliable estimates of Agent Orange exposure, and analyses of selected subgroups of Vietnam veterans reported positive associations. Overall, epidemiologic research offers no consistent or convincing evidence of a causal relationship between exposure to Agent Orange or TCDD and prostate cancer. More accurate exposure assessment is needed in large epidemiologic studies to rule out a causal association more conclusively.  相似文献   
968.
Lung - To determine the optimal dose of sivopixant, a highly selective P2X3 receptor antagonist, for refractory or unexplained chronic cough (RCC/UCC). In this phase 2b, randomized, double-blind,...  相似文献   
969.
970.
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