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We studied the incidence of cerebral hemorrhage in an animal model of embolic stroke to determine the safety of aspirin, heparin, and tissue plasminogen activator therapies. We occluded the middle cerebral arteries of rabbits with labeled blood clots and administered either tissue plasminogen activator, heparin, aspirin, tissue plasminogen activator plus aspirin, tissue plasminogen activator plus heparin, or saline at various times after stroke. Compared to saline controls, both the aspirin-only and the tissue plasminogen activator-plus-aspirin groups had a significantly higher incidence of cerebral hemorrhage, whereas the heparin and tissue plasminogen activator combination groups did not. We conclude that aspirin antiplatelet therapy alone may increase the risk of hemorrhagic infarction, whereas heparin or tissue plasminogen activator therapy appears to be relatively safe.  相似文献   
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Despite a high prevalence of chronic muscle pain disorders such as fibromyalgia and regional myofascial pain, there is still limited knowledge about the factors that initiate and perpetuate these pain states. Although there are also likely to be downstream neuropathic changes in the central nervous system and spinal cord that sustain and exacerbate the pain states known as fibromyalgia, the focus of this critical review is on studies that examined the connection between both fibromyalgia and regional myofascial pain and sympathetic function. Specifically, we looked at studies that described Raynaud-like symptoms, cardiovascular dysfunction and altered intramuscular perfusion in chronic muscle pain. Our analysis showed that although the first 2 phenomena were intermittently present, a prominent and consistent feature for regional myofascial pain and to a lesser degree for fibromyalgia was intramuscular hypoperfusion. Several hypotheses can be offered why this hypoperfusion exists, and additional studies comparing and contrasting these theories are needed. This review focuses on one of these theories, namely, agonist-induced beta-adrenergic receptor desensitization as an explanatory model for hypoperfusion. What cannot be done at this time and is needed in the future is to compare and contrast to what degree the regional muscle pain disorder (myofascial) is similar or different from the more generalized disorder (fibromyalgia).  相似文献   
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The purpose of this study was to identify perceived barriers to independent community living and employment among clients and staff members in a transitional living facility for persons with AIDS. This qualitative study used focus groups to collect these perceptions from staff members (N = 21) and clients (N = 16). Whereas staff identified both systemic and personal barriers, clients only identified systemic barriers. These findings suggest that both clients and staff recognize the types of environmental barriers to participation that have been identified by disability scholars. The findings also underscore a consequential gap between clients' exclusive emphasis on environmental barriers and staff emphasis on clients' personal barriers that impact upon participation.  相似文献   
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Heart failure is reaching epidemic proportions in the United States, causing a constellation of disabling symptoms. Cognitive impairment in people with heart failure may be more common than previously known with multiple etiologies from both the disease process and the treatment. Exemplars from a research study are used to illustrate the perspective of heart failure patients. Given the critical importance of memory deficits on patient education, potential nursing interventions to address the issue of cognitive impairment are described.  相似文献   
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Designed to help persons with schizophrenia to persist and perform better at job placements, the Indianapolis Vocational Intervention Program (IVIP) is a program of cognitive-behavioral group and individual interventions. While its feasibility has been previously demonstrated, it is unknown whether IVIP assists persons to achieve greater levels of participation in vocational rehabilitation and higher levels of job performance. In this study, 100 participants with schizophrenia or schizoaffective disorder were offered a six month job placement and randomized to receive IVIP (n = 50) or support services (n = 50) matched for treatment intensity. Number of hours worked was recorded weekly and job performance was assessed biweekly using the Work Behavior Inventory with raters blind to condition. t-tests revealed that participants in the IVIP group worked a significantly greater number of weeks than those in the support condition. Also, repeated measures ANOVA revealed the IVIP group worked more hours across that 26 week period as well. And with regards to work performance, repeated measures of the 56 participants who worked for at least two-thirds of the intervention revealed that participants in the IVIP group had generally better work performance than those in the support condition. Results suggest a connection between cognitive-behavioral interventions and higher levels of work performance in people with schizophrenia.  相似文献   
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Phytochemical-mediated modulation of P-glycoprotein (P-gp) and other drug transporters may give rise to many herb-drug interactions. Serial plasma concentration-time profiles of the P-gp substrate, digoxin, were used to determine whether supplementation with goldenseal or kava kava modified P-gp activity in vivo. Twenty healthy volunteers were randomly assigned to receive a standardized goldenseal (3210 mg daily) or kava kava (1227 mg daily) supplement for 14 days, followed by a 30-day washout period. Subjects were also randomized to receive rifampin (600 mg daily, 7 days) and clarithromycin (1000 mg daily, 7 days) as positive controls for P-gp induction and inhibition, respectively. Digoxin (Lanoxin, 0.5 mg) was administered p.o. before and at the end of each supplementation and control period. Serial digoxin plasma concentrations were obtained over 24 h and analyzed by chemiluminescent immunoassay. Comparisons of area under the curve (AUC)((0-3)), AUC((0-24)), C(max,) CL/F, and elimination half-life were used to assess the effects of goldenseal, kava kava, rifampin, and clarithromycin on digoxin pharmacokinetics. Rifampin produced significant reductions (p < 0.01) in AUC((0-3)), AUC((0-24)), CL/F, t(1/2), and C(max), whereas clarithromycin increased these parameters significantly (p < 0.01). With the exception of goldenseal's effect on C(max) (14% increase), no statistically significant effects on digoxin pharmacokinetics were observed following supplementation with either goldenseal or kava kava. When compared with rifampin and clarithromycin, supplementation with these specific formulations of goldenseal or kava kava did not appear to affect digoxin pharmacokinetics, suggesting that these supplements are not potent modulators of P-gp in vivo.  相似文献   
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