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With the advent of new digital technology into public telecommunications networks and given the fact that voice and data are carried in essentially the same way across a digital network, it is realized that the integration of voice and data services is possible and cost effective, and may bring additional benefits. The paper sets out some of the current developments in this area, with an emphasis on British Telecom's pilot Integrated Services Digital Network.  相似文献   
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It has been postulated that delayed facilitation of norepinephrine release by epinephrine is causally related to the development of hypertension. It has been proposed that a brief increase in epinephrine concentrations results in the uptake of epinephrine into the sympathetic nerve terminal. Subsequent rerelease of epinephrine stimulates presynaptic beta-adrenergic receptors, resulting in a prolonged increase in plasma norepinephrine (NE) concentrations, with amplified sympathetic responses and vasoconstriction. To determine whether such epinephrine-induced, delayed facilitation of NE release occurs in a vascular bed draining resistance vessels and, if it occurs, whether that facilitation differs in hypertension, we used a radioisotope dilution method to measure unstimulated and isoproterenol-stimulated forearm NE spillover before, during, and after a 50 ng/min infusion of epinephrine for 30 minutes directly into the brachial artery. No delayed facilitatory effects of epinephrine on forearm NE spillover were observed in either 6 normotensive (NT) or 8 borderline hypertensive (BHT) subjects (NT unstimulated forearm NE spillover preepinephrine 1.79+/-0.41 ng/min versus postepinephrine 2.36+/-0.65 ng/min, P=.38; BHT preepinephrine 2.24+/-0.70 ng/min versus postepinephrine 1.93+/-0.46 ng/min, P=.51; NT isoproterenol-stimulated forearm NE spillover preepinephrine 4.61+/-1.01 ng/min versus postepinephrine 4.4+/-0.98 ng/min, P=.9; BHT preepinephrine 4.04+/-1.36 ng/min versus postepinephrine 4.69+/-1.49 ng/min P=.5). We conclude that the short-term local infusion of epinephrine does not have a delayed facilitatory effect on forearm NE spillover in NT or BHT subjects. Therefore, the prolonged increase in NE concentrations after epinephrine infusion previously shown systemically, and not seen locally in the forearm, suggests that the delayed facilitatory response to epinephrine may occur in other organs.  相似文献   
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The precise diagnosis of paracoccidioidomycosis, in most cases, is established by direct methods and indirect immunological tests. The latter method is reliant on the identification of the host's humoral responses, which are usually impaired or absent in patients with severe juvenile forms of the disease and in immunocompromised patients. Determining disease activity or assessing treatment responses by measuring antibody levels is difficult, since antibody titer may remain elevated or persist at stationary levels, even in the presence of clinical improvement. Consequently, there is a need for alternative tests aimed at the identification of circulating antigens. A modification of the standard hybridoma production method was used to raise a panel of murine monoclonal antibodies (MAbs) against the yeast form of Paracoccidioides brasiliensis. Of these, MAb PIB, directed against an 87-kDa determinant, was used to develop an inhibition ELISA (inh-ELISA) capable of detecting as little as 5.8 ng of circulating antigen per ml of serum. Sera from 46 patients with paracoccidioidomycosis or other mycoses and sera from healthy individuals were evaluated by the inh-ELISA; overall sensitivity was 80.4% (37 of 46 paracoccidioidomycosis patients tested positive), and specificity compared with that of normal controls from areas of endemicity was 81.4%. The inh-ELISA detected circulating antigen in 100% of patients with the acute form of paracoccidioidomycosis and in 83.3 and 60% of patients with the chronic multifocal and unifocal forms of paracoccidioidomycosis according to the patients' clinical presentation. These results indicate that the inh-ELISA with MAb PIB is effective in the detection of circulating antigen and that this test may be useful for monitoring responses to treatment and establishing disease prognoses.  相似文献   
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Alzheimer's disease (AD) is a common cause of functional decline in Down syndrome (DS) adults. Acquired cognitive deficits may be difficult to evaluate in the context of baseline impairments. Behavioral symptoms are also common and may represent the effects of depression, AD, or both. Therefore, the objective of this study was to report a clinical case series of selected adults with DS and behavioral change who responded to treatment with selective serotonin-reuptake inhibitor (SSRI) medication. Six patients, aged 23 to 63 years, 5 women and 1 man, with the clinical diagnosis of DS presented for diagnosis and treatment of functional decline in adult life. Noncognitive symptoms were prominent and included aggression, social withdrawal, and compulsive behaviors. Memory dysfunction was reported in varying degrees. Treatment with SSRI antidepressants was instituted for depressive, apathetic, and compulsive behaviors. Treated patients showed improvement in behaviors as reported by caregivers, and on objective measures, such as workplace productivity. Noncognitive symptoms are a cardinal feature of functional decline in adults with DS and may represent either depression or AD. In some patients, the symptoms respond well to SSRI agents with concomitant improvement in daily function. Treatment trials with SSRIs may, therefore, be warranted in such cases.  相似文献   
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