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71.
The N-terminal domain of Clostridium perfringens alpha-toxin, homologous with the nontoxic phospholipase C of Bacillus cereus, was expressed in Escherichia coli and shown to retain all of the phosphatidylcholine hydrolyzing activity of the alpha-toxin, but not the sphingomyelinase, hemolytic, or lethal activities. The C-terminal domain of alpha-toxin showed sequence and predicted structural homologies with the N-terminal region of arachidonate 5-lipoxygenase, an enzyme from the human arachidonic acid pathway which plays a role in inflammatory and cardiovascular diseases in humans.  相似文献   
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Cerebral blood flow and glucose utilization were measured in rat neocortex, hippocampus and striatum following methylenedioxymethamphetamine injection (5 mg/kg, i.v.), using the tracers [14C]iodoantipyrine and [14C]2-deoxyglucose, respectively. In control rats, blood flow was coupled to glucose metabolism, but in methylenedioxymethamphetamine-treated rats, marked hyperperfusion was measured in frontal and parietal cortex with no change in glucose use. This suggests that methylenedioxymethamphetamine has the potential to disrupt cerebrovascular control.  相似文献   
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Normal pressure hydrocephalus (NPH) is a neurological disorder characterized by a triad of symptoms: gait disturbance, dementia, and urinary incontinence. To date, the treatment of choice is cerebrospinal fluid diversion with a shunt. Because the clinical presentation of NPH mimics other neurological disorders, or can be perceived by healthcare providers as a natural aging process, it can be misdiagnosed or go undetected for many years. Patients with NPH suffer from debilitating physiological impairments as well as psychological disturbances. There are many different healthcare concerns in this population, including quality-of-life and safety issues. To achieve a more expedient diagnosis and treatment plan, nurses must be educated about this disorder.  相似文献   
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INTRODUCTION: Health care workers have long been recognized as having a high risk of work-related assault. In response to a growing threat of violence in hospitals, California implemented the Hospital Security Act (AB508) in 1993. This study compares surveys of emergency nurses before and after implementation of AB508. METHODS: In 1990, the CAL/ENA surveyed emergency departments in California to enumerate violent events and describe security programs. Using the CAL/ENA membership directory, hospitals were resurveyed in 2000 to identify changes from the original survey. Surveys were mailed to the ED nurse manager or equivalent. Survey responses were anonymous. RESULTS: Most hospitals reported fewer violent episodes after the implementation of AB508. However, 32% of hospitals reported that 5 or more verbal threats occurred monthly, and 5% reported that 5 or more violent injuries occurred monthly. Overall, hospitals reported improvements in security programs. The most notable increase was in employee training, which rose from 34% to 95.6% of reporting hospitals. However, almost a quarter of hospitals reported not having general violence prevention policies, and many believed that security personnel were inadequate. DISCUSSION: Although results reported here cannot be directly attributed to AB508, the increase in security program components suggests that hospitals are responding positively to reduce violence. The high prevalence of threats and violent events reported indicates a persistent risk of violence against health care workers.  相似文献   
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