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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   
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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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