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Amyloidosis is a systemic disease caused by abnormal deposition of amyloid material that is detected with Congo red staining and is difficult to diagnose. Involvement of the tracheobronchial tree is rare and is a challenge for pulmonologists because of the wide differential diagnosis of this disease. We present two cases where tracheobronchial affectation has been observed: in one of them as a primary disease, and in another as secondary affectation. The use of bronchoscopic techniques is essential for the diagnosis of tracheobronchial involvement. In the absence of an effective drug therapy, local management of this disease with endoscopic techniques for bronchial repermeabilization is able to provide clinical improvement and expand the treatment options and prognosis in this disease.  相似文献   
74.
This study was conducted to 1) assess the effectiveness of an experimental two-way cable TV system in reaching the older people for whom it was designed, and 2) assess the attraction of this locally-based age-targeted system for its viewers. The study evaluates the system's effectiveness in reaching its target audience by examining information about the types of viewers—both younger and older—who have been attracted to the system. In addition, differences in factors that predict viewing frequency for younger and older people are used to illuminate life stage differences in people's attraction to locally-based TV programming. Findings show that the system had successfully reached its target audience within two years of inception. Watching the interactive TV programs because of the system's provision of information about local events and because of the senior citizens' focus strongly predicted viewing frequency for both older and younger respondents. The ability of locally-based interactive TV programming to serve social and informational needs of older people which are unmet by traditional broadcast television is discussed.  相似文献   
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Type II deiodinase (D2) activates thyroid hormone by converting thyroxine (T4) to 3,5,3′-triiodothyronine (T3). This allows plasma T4 to signal a negative feedback loop that inhibits production of thyrotropin-releasing hormone (TRH) in the mediobasal hypothalamus (MBH) and thyroid-stimulating hormone (TSH) in the pituitary. To determine the relative contributions of these D2 pathways in the feedback loop, we developed 2 mouse strains with pituitary- and astrocyte-specific D2 knockdown (pit-D2 KO and astro-D2 KO mice, respectively). The pit-D2 KO mice had normal serum T3 and were systemically euthyroid, but exhibited an approximately 3-fold elevation in serum TSH levels and a 40% reduction in biological activity. This was the result of elevated serum T4 that increased D2-mediated T3 production in the MBH, thus decreasing Trh mRNA. That tanycytes, not astrocytes, are the cells within the MBH that mediate T4-to-T3 conversion was defined by studies using the astro-D2 KO mice. Despite near-complete loss of brain D2, tanycyte D2 was preserved in astro-D2 KO mice at levels that were sufficient to maintain both the T4-dependent negative feedback loop and thyroid economy. Taken together, these data demonstrated that the hypothalamic-thyroid axis is wired to maintain normal plasma T3 levels, which is achieved through coordination of T4-to-T3 conversion between thyrotrophs and tanycytes.  相似文献   
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In this illustrative case, rheumatoid disease changed an active, self-supporting woman into a disabled, dependent and depressed person. When disease activity is continuous, early efforts to prevent severe deformity take on great urgency. It is also important to alleviate the psychosocial impact of the disease, which may well be more than even a highly motivated patient can handle alone.  相似文献   
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Statins are an extensively used class of drugs, and myopathy is an uncommon, but well-described side effect of statin therapy. Inflammatory myopathies, including polymyositis, dermatomyositis, and necrotizing autoimmune myopathy, are even more rare, but debilitating, side effects of statin therapy that are characterized by the persistence of symptoms even after discontinuation of the drug. It is important to differentiate statin-associated inflammatory myopathies from other self-limited myopathies, as the disease often requires multiple immunosuppressive therapies. Drug interactions increase the risk of statin-associated toxic myopathy, but no risk factors for statin-associated inflammatory myopathies have been established. Here we describe the case of a man, age 59 years, who had been treated with a combination of atorvastatin and gemfibrozil for approximately 5 years and developed polymyositis after treatment with omeprazole for 7 months. Symptoms did not resolve after discontinuation of the atorvastatin, gemfibrozil, and omeprazole. The patient was treated with prednisone and methotrexate followed by intravenous immunoglobulin, which resulted in normalization of creatinine kinase levels and resolution of symptoms after 14 weeks. It is unclear if polymyositis was triggered by interaction of the statin with omeprazole and/or gemfibrozil, or if it developed secondary to long-term use of atorvastatin only.  相似文献   
80.
Basic fibroblast growth factor (bFGF) is a potent angiogenic factor produced by cells of mesodermal and neuroectodermal origin. Despite numerous advances, the precise mechanism of bFGF release from cells still remains unknown. Upon release from cells, the protein is stored and protected in the extracellular matrix by binding to heparan sulfate proteoglycans. A number of reports suggest that degrading enzymes secreted by mast cells may play a role in the release of bFGF from connective tissue stores. Additionally, mast cells are believed to play a role in the formation of new blood vessels. In this report, we studied the events involved in neovascularization using a well-characterized model of angiogenesis in rabbits where neovascularization is induced by transfer of a well-perfused rectus abdominis muscle flap to an ischemic limb. Using this model, we demonstrate that bFGF expression is induced in normal myofibers and bFGF is released in the wound fluid at the ischemic/nonischemic interface. The highest concentrations of bFGF were detected on days 14 and 21 postoperation. We also show that the number of mast cells and their degranulation correlate with the release of bFGF from adjacent muscle tissue and the appearance of the growth factor in the wound fluid. There appears to exist a temporal correlation between number of mast cells, their degranulation, and the release of bFGF during angiogenesis in vivo.  相似文献   
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