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61.
BACKGROUND: Abnormal smooth pursuit eye movement (SPEM) in schizophrenic patients is a well known phenomenon, but the neurophysiological mechanisms underlying the deficit are unknown. Nicotine temporarily improves SPEM and has been associated with reduced hippocampal hemodynamic activity in schizophrenics. Nicotine's effect on brain activity in control subjects performing SPEM has not been studied. The purpose of this work was to determine if nicotine differentially affects brain activity in schizophrenic and control subjects during pursuit eye tracking. METHODS: 16 subjects with schizophrenia and 16 control subjects underwent functional MR imaging during SPEM after receiving placebo or nicotine gum. Four brain regions were analyzed for main effects of group, drug, and interactions: hippocampus, cingulate gyrus, frontal eye fields, and area MT. RESULTS: Nicotine reduced hippocampal activity in both groups, but the effect was greater in control subjects. A group by drug interaction was observed in the anterior cingulate gyrus, where nicotine decreased activity in control subjects and increased activity in schizophrenic subjects. There were no significant effects of group, drug, or interactions in frontal eye fields or area MT. CONCLUSIONS: Nicotine may improve SPEM performance in people with schizophrenia through cholinergic stimulation of the hippocampus and cingulate gyrus. Potential mechanisms include improved inhibitory function and attention.  相似文献   
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PURPOSE: The purpose of the study was to evaluate the incidence of incontinence pad use among patients admitted to medical wards, the reasons why nurses decide to use an incontinence pad, the extent to which the use of pads is avoidable, and the outcome of inappropriate pad use after discharge from the hospital. METHODS: A prospective cohort study was conducted; patients admitted to medical wards were observed during hospitalization and a 7-day follow-up period after discharge. SUBJECTS AND SETTING: The study was conducted in 2 acute-care units in Northern Italy. All new patients admitted to the units were recruited. RESULTS: At the time of admission to the hospital, in addition to the 120 patients who already used incontinence pads, there was a 34% incidence of new cases (98/286). The most frequent reason why nurses decided to use this aid was incontinence caused by space-time disorientation, followed by limited mobility, incontinence, patient request, nursing shortage, and involuntary urine leakage not perceived by patient. Seventy patients out of 208 used incontinence pads unnecessarily for a total of 544 days. CONCLUSIONS: Decisions about the use of the incontinence pads are not always consistent with research-based or literature-based suggestions. Nurses should develop clinical guidelines or protocols for the appropriate use of incontinence pads.  相似文献   
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Objective  

To estimate the duration of work life among persons reporting a physician's diagnosis of COPD, asthma, or rhinitis compared to those with select non-respiratory conditions or none and to delineate the factors associated with continuance of employment.  相似文献   
65.
Evidence based guidelines for medical nutrition therapy (MNT) in chronic kidney disease (CKD) recommend a range of caloric levels, dependent on age and level of kidney function. Recent literature has explored whether current research findings still support these earlier conclusions, and if new energy determinations for CKD are warranted. This review will take a brief look at the history of the controversy, examine the research evidence at the time of practice guideline development, investigate emerging research, and discuss implications for additional scientific inquiry.  相似文献   
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Because of their excellent slice profiles and high immunity to RF inhomogeneity, adiabatic full passage (AFP) pulses are ideal for use in spatial localization. The nonlinear, position-dependent phase of a single AFP pulse generated during refocusing of transverse magnetization traditionally is eliminated by using identical pairs of AFP pulses, at the expense of increased RF power deposition and increased echo time (TE). Here it is shown that one can achieve significant phase refocusing by executing single AFP pulses along non-equivalent spatial axes. When used for volume selection in MR spectroscopic imaging (MRSI) the remaining nonlinear phase becomes inconsequential when the phase across a spectroscopic volume is small. Selection of rectangular and octagonal volumes is demonstrated with half the number of AFP pulses used in the traditional approach. It is shown that octagonal volume selection in the human brain provides excellent suppression of extracranial lipids, and thus allows multislice (1)H MRSI at 4 Tesla to be performed within the guidelines for RF power deposition.  相似文献   
69.

Background  

A multi-state consortium was developed in the US to conduct baseline data collection and intervention research on fetal alcohol syndrome. Each state employed support specialists whose job it was to reduce or eliminate alcohol consumption in women who were at high risk for drinking alcohol during their pregnancy. The purpose of this paper is to report how support specialists in three primarily rural/frontier states were trained to assess client need and how client need was actually assessed in the field.  相似文献   
70.
OBJECTIVE: We compared 2 techniques for performing a partial salpingectomy by using microlaparoscopy and either bipolar coagulation or loop ligation. METHODS: A 3-mm transumbilical laparoscope with secondary midline port sites midway and suprapubically was used to perform a partial salpingectomy in 109 women desiring permanent sterilization. Each patient was randomly assigned to undergo a tubal resection either after Pomeroy ligation (n= 54) or after bipolar coagulation with Kleppinger forceps (n=55). Postoperative pain, as assessed using a 10-point visual analog scale, was the primary comparison endpoint. RESULTS: No technical difficulties with either technique required conversion to a minilaparotomy. The mean time to remove both tubal segments was not different between techniques (7 minutes, 21 seconds; range, 4 minutes, 25 seconds to 15 minutes, 43 seconds). Each segment (mean, 1.6 cm; range, 0.8 to 3.5 cm) was confirmed in the operating room, then histologically. Postoperative pain at 6 hours was scored similarly (median, ligation 4.6, coagulation 4.0 of 10). Outpatient recovery was the same, unless pelvic pain required overnight observation (ligation, 4 patients; coagulation, 2 patients). CONCLUSION: Partial salpingectomy, using microlaparoscopy with either bipolar coagulation or loop ligation, was performed with comparable ease, confirmation of the removed tube, and similar postoperative discomfort.  相似文献   
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