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21.
Joel R. Saper  MD  FACP  FAAN 《Headache》2006,46(S3):S151-S156
The famous question, "Are you talking to me?," was coined by Robert DeNiro in his lead role as Travis Bickle in the Martin Scorsese classic, Taxi Driver . The phrase also characterizes the troubling encounters that many headache-treating professionals confront as they attempt to discuss serious matters of care and compliance with some of their headache patients. Although most headache patients are eager to take professional advice and guidance, there exists a minority of patients whose behavior undermines a collaborative relationship between doctor and patient. In these cases, the physician may need to directly confront this behavior in order to overcome behavioral barriers that interfere with desirable treatment outcomes. This article offers explicit means and strategies to engage difficult patients, increase the likelihood of program adherence and improvement, and develop a more satisfying doctor-patient relationship, based on clinical experience in a national referral center for difficult-to-manage headache patients.  相似文献   
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Background  

While gastrointestinal problems are common in ICU patients with multiple organ failure, gastrointestinal failure has not been given the consideration other organ systems receive. The aim of this study was to evaluate the incidence of gastrointestinal failure (GIF), to identify its risk factors, and to determine its association with ICU mortality.  相似文献   
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PURPOSE: To compare the quality of care in teaching hospitals with that in nonteaching hospitals. METHOD: By performing a literature review via PubMed, the author identified and surveyed 23 studies that compared the quality of care in teaching hospitals with that in nonteaching hospitals. The studies were published from 1989-2004 and in all but one case dealt exclusively with U.S. hospitals. RESULTS: The teaching hospitals studied had better-quality measures than did nonteaching hospitals in the predominant number of studies reviewed. Process measures were significantly better in teaching hospitals in seven of the eight studies where such measures were observed, and equal in the other study. Risk-adjusted mortality was lower in teaching hospitals in nine of the 15 studies using that measure, not significantly different in five, and significantly lower in nonteaching hospitals in one study (in pediatric intensive care units, even though the teaching hospitals had a better process of care). In nonmortality outcomes, teaching hospitals were better in one study using that measure; there were no significant differences in five other such studies. Major teaching hospitals had more favorable outcomes end points than did minor teaching hospitals in eight studies in which they were compared. Including only those six studies using clinical data for process analysis or risk adjustment, teaching hospitals had a better process in all six and lower adjusted mortality in five of seven studies where that measure was used. CONCLUSIONS: Overall, the favorable results in teaching hospitals extended over a range of locations, conditions, and populations, including routine as well as complex conditions. However, the quality measured in these studies was not at target levels across the spectrum of hospitals. There needs to be a continuous and determined effort for improvement in all institutions. It is to be hoped that teaching hospitals will take the lead not only in continuously improving their own quality, but also in developing and evaluating ever improving methods of quality assessment.  相似文献   
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We report the case of a woman with refractory celiac disease who developed abnormal spontaneous movements of the extremities and face consistent with myorhythmia. Investigation led to a diagnosis of encephalitis, confirmed by postmortem examination. The movements were likely caused by nonparaneoplastic encephalitis associated with refractory celiac disease. Etiologic and diagnostic considerations and treatment options are discussed.  相似文献   
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Low-frequency stimulation is associated with long-term depression (LTD) of synaptic efficacy in various brain structures. Like long-term potentiation (LTP), homosynaptic LTD in area CA1 of the hippocampus appears to require NMDA receptor activation, changes in postsynaptic calcium concentration and phospholipase A2 (PLA2) activation. Arachidonic acid (AA) is released after the activation of calcium-dependent phospholipases and free AA is rapidly metabolized to a family of bioactive products (the eicosanoids) which are thought to be both intracellular and extracellular messengers. In the present study, we investigated the involvement of the cyclooxygenase and lipoxygenase pathways of AA metabolism in the formation of homosynaptic LTD in the rat hippocampus. Stimulation at 1 Hz for 15 min was used to produce homosynaptic depression in area CA1 of hippocampal slices. LTD induction was partially blocked by bromophenacyl bromide (50–100 μM), a selective PLA2 inhibitor, and by the a nonselective lipoxygenase inhibitor nordihydroguaiaretic acid (NDGA; 100 μM). In contrast, the specific cyclooxygenase blocker indomethacin (100 μM) did not significantly reduce hippocampal LTD. Since NDGA interferes with LTD formation, we examined whether specific inhibitors of 5- and 12-lipoxygenases were capable of blocking LTD expression. The 12-lipoxygenase inhibitor baicalein at a concentration of 50 μM reduced LTP formation when given in the bath, an effect that was less pronounced with the 5-lipoxygenase inhibitor AA-861. These data suggest that the activation of endogenous PLA2 and the formation of 12-lipoxygenase metabolites of AA may be important factors controlling the expression of hippocampal LTD.  相似文献   
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During development, discrete cell fates often result from variation in the intensity of a particular signal. The mechanisms underlying these seemingly analog-to-digital switches are not understood. In developing T lymphocytes, low-intensity signals through the antigen receptor result in positive selection while more intense signals give rise to negative selection. By deleting the genetic locus encoding the regulatory B1 subunit of calcineurin specifically in thymocytes, we found an absolute requirement for calcineurin in positive selection. In contrast, calcineurin activity was dispensable in several models of negative selection. Unexpectedly, we found that removal of calcineurin activity from thymocytes results in inefficient ERK activation at the double-positive stage of thymocyte development, when selection occurs. These studies clarify the mechanism by which graded signals are converted to discrete outcomes in T cell development and further indicate that the developmental roles of calcineurin likely contribute to immunosuppression by calcineurin inhibitors.  相似文献   
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The effects of changing bathing medium osmolality on tension generation in smooth muscle were studied on potassium-depolarized segments of rat ileum. Increasing the tonicity of the medium evokes a transient relaxation of the smooth muscle; restoration of isotonicity evokes a transient contraction of similar amplitude and time course. While immersed in hypertonic media of less than 1.3 times normal tonicity, the smooth muscle slowly increases its isometric tension; in media of nearly twice normal tonicity, the smooth muscle loses tension. All of these effects occur whether the medium is made hypertonic with added NaCl or sucrose.  相似文献   
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