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51.
The TNF family ligand B cell-activating factor (BAFF, BLyS, TALL-1) is an essential factor for B cell development. BAFF binds to three receptors, BAFF-R, transmembrane activator and CAML interactor (TACI), and B cell maturation antigen (BCMA), but only BAFF-R is required for successful survival and maturation of splenic B cells. To test whether the effect of BAFF is due to the up-regulation of anti-apoptotic factors, TACI-Ig-transgenic mice, in which BAFF function is inhibited, were crossed with transgenic mice expressing FLICE-inhibitory protein (FLIP) or Bcl-2 in the B cell compartment. FLIP expression did not rescue B cells, while enforced Bcl-2 expression restored peripheral B cells and the ability to mount T-dependent antibody responses. However, many B cells retained immaturity markers and failed to express normal amounts of CD21. Marginal zone B cells were not restored and the T-independent IgG3, but not IgM, response was impaired in the TACI-IgxBcl-2 mice. These results suggest that BAFF is required not only to inhibit apoptosis of maturating B cells, but also to promote differentiation events, in particular those leading to the generation of marginal zone B cells.  相似文献   
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The neurological and psychiatric manifestations in a case of Urbach-Wiethe's disease are reported. The present case is characterized by the predominance of cerebral symptoms: ataxia, psychomotoric seizures, paranoic hallucinatory psychosis and attacks of rage. At autopsy, deposits of amyloid-like material in the walls of the brain vessels could be observed. This finding, together with the mucocutaneous alterations, confirmed the diagnosis of the rare disease know as "lipoid proteinosis cutis et mucosae".  相似文献   
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Summary The chronotropic response to a single oral dose of propranolol in 23 healthy subjects has been related to the plasma propranolol concentration and the density of -adrenoceptors on peripheral polymorphonuclear leucocytes. The percentage reduction in exercise-induced tachycardia was significantly correlated with the log plasma propranolol concentration within subjects but not between subjects. Taking the concentration of the active metabolite 4-hydroxypropranolol into account did not improve the interindividual correlation. The reduction in exercise-induced tachycardia was significantly correlated with the maximum binding density of (125I)-hydroxybenzylpindolol on polymorphonuclear leucocyte membrane fragments measured before medication. A response index (% reduction in exercise-induced tachycardia/plasma propranolol concentration) was correlated with the maximum binding density of (125I)-hydroxybenzylpindolol (predrug) at 2 h (rs=0.72), 4 h (rs=0.84) and 6 h (rs=0.73) after dosing. The data suggest that interindividual variation in the response to propranolol after a single oral dose is determined by interindividual differences both in plasma propranolol and adrenoceptor density.  相似文献   
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The Family Violence Option (FVO) was designed to help survivors of domestic violence (DV) more easily secure income support in the United States (U.S.), without placing them at risk of further abuse. The objective of this study is to determine whether the decision-making of advocates responsible for determining waiver recommendations under the FVO is influenced by the relationship status of DV survivors. Recursive partitioning was used to analyse data from a sample of 237 survivor risk assessments from four New Jersey counties to determine which women receive waiver recommendations and which do not. Advocates completed risk assessments for the women and were instructed to make recommendations on waivers based on their assessment. Workers’ decision-making was examined using classification and regression trees (CART) to determine what case factors made it more or less likely for survivors to be recommended waivers. The CART results were supplemented with logistic regression analyses to ensure validity. For two of three waivers, survivors who reported currently residing with their abuser or who had ended the relationship recently were less likely to receive waiver recommendations than those who had been out of the relationship for a longer period of time (OR = 0.09–0.21), even when accounting for the type and severity of DV and the impacts of the violence on survivors’ mental health. The results indicate that DV advocates’ decision-making is complicated by factors independent of survivors’ case characteristics. This can affect the safety and well-being of women attempting to leave violent relationships by affecting their access to resources.  相似文献   
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A detailed analysis of homing in pigeons and small mammals has remained difficult because the paths of the animals could not be reconstructed precisely. Here, we describe a lightweight global position system (GPS) data logger (35 g including battery and casing; 40 x 68 x 18 mm) that records the flight of pigeons and the path of dogs with an accuracy of +/-12 m. With one battery, the logger runs in continuous mode (1 fix/s) for 3.5 h and in power-saving mode (1 fix/5 s) for about 16 h, and stores a maximum of 100,000 data points that are downloaded to a PC. A module of our public domain software WINTRACK permits a detailed numerical and graphical analysis of path geometry, phases of resting and moving, and path similarity. The device can be adapted to different species provided that satellite signals can be received reliably and that the loggers can be recovered. We expect it to be useful for testing hypotheses about pigeon homing, assessing natural spatial behavior and orientation of many species, and anticipate further miniaturization.  相似文献   
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Cardiac myxomas     
Cardiac myxoma is the most common primary tumor of the heart. Between 1970 and 1998, 33 myxomas from patients operated at the Cardiosurgical Department were submitted for pathological examination. A review of age, sex and clinical symptoms of the patients as well as of gross and histological features of the tumors is presented. Immunohistochemical examination was performed on 10 selected myxomas-reactivity to vimentin, desmin, S-100 protein, cytokeratin and FVIIIR-Ag. The necessity of histological examination of the embolectomy material is stressed.  相似文献   
60.
Demonstrated are eight cases of carcinoid heart disease (7 females, 1 male; average age 63.4 y.). The primary tumor was localized in the ileum in 5, and in the cecal area in 3 patients, with liver metastases in each case. The characteristic heart lesion appears as an endocardial plaque composed of loose intercellular matrix with scattered smooth muscle cells, covered by an endothelial layer. The plaques are apposed on an otherwise normal valvular, or mural endocardium of the right heart. The resulting combined valvular lesions show a predominance o tricuspid incompetence, or of pulmonary stenosis. In one case with a widely patent foramen ovale there was involvement of left-heart valves in addition. Local effect of serotonin appears to play the main role in pathogenesis of the endocardial plaques.  相似文献   
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