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51.
Propofol anaesthesia may reduce postoperative emesis. The purpose of this study was to compare the incidence of emesis after propofol anaesthesia with and without nitrous oxide, compared with thiopentone and halothane anaesthesia, in hospital and up to 24 hr postoperatively, in outpatient paediatric patients after strabismus surgery. Seventy-five ASA class I or II, unpremedicated patients, aged 2–12 yr were randomly assigned to one of three groups: Thiopentone, 6.0 mg · kg? 1 iv induction followed by halothane and N2O/O2 for maintenance (T/H); propofol for induction, followed by propofol and oxygen for maintenance (P/O2); and propofol for iv induction, followed by propofol infusion and N2O/O2 for maintenance (P/N2O). All received vecuronium, controlled ventilation, and acetaminophen pr. Morphine was given as needed for postoperative analgesia. There were no differences in age, weight, number of eye muscles operated upon, duration of anaesthesia or surgery. The P/N2O group (255 ± 80 μg· kg? 1· min? 1) received less propofol than the P/O2 group (344 ± 60 μg · kg? 1· min? 1) (P ≤ 0.0001) and had shorter extubation (P < 0.001) and recovery (P < 0.01) times. Emesis in the hospital, in both the P/N2O (4.0%) and P/O2 group (4.0%) was less than in the T/H group (32%) (P < 0.01). Antiemetics were required in four patients in the T/H group (16.0%). Overall emesis after surgery was not different among the groups: T/H (48%), P/O2 (28%) and P/N2O (42%). The use of propofol anaesthesia with and without N2O decreased only early emesis. This supports the concept of a short-acting, specific antiemetic effect of propofol.  相似文献   
52.
From 1990 to 1991 in the Hobart region there was a marked fall in both hotel patronage and the proportion of patrons subsequently driving with their blood alcohol concentration above the legal limit. This was associated with smaller falls in the number of drink drivers charged and alcohol-related road accidents, which continued in the following year. It appears that the pattern of drinking and driving is changing, presumably in response to random breath testing and tougher penalties for offences.  相似文献   
53.
Purpose: To describe the service utilization patterns of homeless and runaway youth in a “service-rich” area of Los Angeles, California; identify demographic and other correlates of utilization; and contextualize the findings with qualitative data.

Method: During Phase 1 of this study, survey data were collected from an ethnically diverse sample of 296 youth aged 13–23 years, recruited from both service and natural “hang-out” sites using systematic sampling methods. During Phase 2, qualitative data were collected from 46 youth of varying ethnicities and lengths of time homeless.

Results: Drop-in centers and shelters were the most commonly used services (reported by 78% and 40%, respectively). Other services were used less frequently [e.g., medical services (28%), substance abuse treatment (10%) and mental health services (9%)]. Utilization rates differed by ethnicity, length of time in Los Angeles, and city of first homeless episode (Los Angeles versus all others). Shelter use was strongly associated with use of all other services. Despite youths’ generally positive reactions to services, barriers were described including rules perceived to be restrictive, and concerns youth had about confidentiality and mandated reporting. Youth suggested improvements including more targeted services, more long-term services, revised age restrictions, and more and/or better job training and transitional services to get them off the streets.

Conclusions: Because shelters and drop-in centers act as gateways to other services and offer intervention potential for these hard-to-reach youth, it is vital that we understand the perceived barriers to service utilization.  相似文献   

54.
PURPOSE: To describe the service utilization patterns of homeless and runaway youth in a "service-rich" area (Los Angeles, California); identify demographic and other correlates of utilization; and contextualize the findings with qualitative data. METHOD: During Phase 1 of this study, survey data were collected from an ethnically diverse sample of 296 youth aged 13-23 years, recruited from both service and natural "hang-out" sites using systematic sampling methods. During Phase 2, qualitative data were collected from 46 youth of varying ethnicities and lengths of time homeless. RESULTS: Drop-in centers and shelters were the most commonly used services (reported by 78% and 40%, respectively). Other services were used less frequently [e.g., medical services (28%) and substance abuse treatment (10%) and mental health services (9%)]. Utilization rates differed by ethnicity, length of time in Los Angeles, and city of first homeless episode (Los Angeles vs. all others). Shelter use was strongly associated with use of all other services. Despite youths' generally positive reactions to services, barriers were described including restrictive rules, confidentiality and reporting problems, and negative interactions with staff members. Youth suggested improvements including more targeted services, more long-term services, revised age restrictions, and more and/or better job training and transitional services to get them off the streets. CONCLUSIONS: Because shelters and drop-in centers act as gateways to other services and offer intervention potential for these hard-to-reach youth, it is vital that barriers to use of these services are eliminated.  相似文献   
55.
Despite introduction of numerous smoking prevention programs in schools, tobacco use has not declined among adolescents. Schools face the dilemma of what to do with students who smoke and are not ready to quit. This study evaluated two programs based on the stages of change model. The educational program, the Tobacco Education Group (TEG), was designed for adolescents not yet thinking about quitting. The cessation program, the Tobacco Awareness Program (TAP), was intended for adolescents who want to quit. Evaluation was completed on 351 students at six public high schools. Compared to a control group of adolescent smokers not assigned to programs, both intervention groups significantly decreased tobacco use. Self-reported use was validated biochemically. Self-efficacy for quitting increased in both programs. Posttest use was predicted by posttest self-efficacy, peer support, and parental support, after controlling for initial use and initial self-efficacy.  相似文献   
56.
This study compared the haemodynamic effects of subarachnoid block with plain bupivacaine 0.5% (dextrose-free), heavy bupivacaine 0.5% (in dextrose 8%) and a mixture of these two solutions, i.e. bupivacaine 0.5% in dextrose 4%. Thirty-six male patients, aged 55-89 years, undergoing transurethral surgery were recruited. Invasive systolic arterial and central venous pressures were recorded at 5-s intervals after the block was initiated using a computerised data-collection system. The height of sensory blockade was recorded at 5-min intervals. No preload was given and episodes of hypotension were treated with colloid (8 ml x kg(-1)) and, if this was ineffective, a metaraminol infusion. Systolic arterial and central venous pressures decreased in all three groups following block (p < 0.05). These decreases were more rapid in onset in the heavy bupivacaine group compared with plain bupivacaine group (p < 0.005). Patients in the heavy bupivacaine group also had a greater requirement for early treatment of hypotension (< 10 min) and treatment with metaraminol (p < 0.05). The onset of sensory blockade was more rapid in the heavy group compared with the mixed group, although final sensory levels were similar. The onset of haemodynamic and sensory changes are more rapid when using heavy bupivacaine intrathecally. This leads to a higher and earlier incidence of hypotension and requirement for treatment.  相似文献   
57.
58.
Communication can be thought of as a message that is sent, received, and understood. Each discipline of the health profession has its own jargon and means of expressing ideas in shorthand. These separate forms of communicating are effective among those of the same background but are often at the root of misunderstandings between professional groups. This article reviews communication theory and traces the difficulties created when inter-disciplinary teams of healthcare try to work together and communicate. As multi-disciplinary teams are increasingly dealing with the complex problems of today's healthcare system, clear communication and understanding has never been more important. If educators could assist in creating an understanding of vocabulary used for decision processes, communication could improve. The authors of this study performed a multi-stage Delphi survey that grouped terms used by administrators and clinicians and produced a lexicon of corresponding terms. An expert panel then reviewed and modified the list. The result is a lexicon that can be useful to assist clinicians and administrators to communicate with each other. By utilizing clinical terminology, or vice versa, instead of management or clinical jargon, some of the translation done by administration or clinicians could be reduced. Examples of how the lexicon can be utilized are provided in the article. This includes using it in health administration education to demonstrate the variances in clinical/managerial terms. It could also be provided as a primer to physicians, nurses, and other health professionals who assume administrative positions to enhance their communication with administrators.  相似文献   
59.
60.
A group B streptococcus (GBS) isolated from human neonates diagnosed with sepsis and respiratory distress (early-onset disease) produces a polysaccharide exotoxin (GBS toxin) that, when infused in sheep, causes lung pathophysiology similar to that seen in humans. Histological studies have demonstrated that GBS toxin induces a strong inflammatory response in the lung, with pulmonary sequestration of granulocytes and extensive capillary endothelial damage. The susceptibility of humans to GBS toxin is age-dependent and limited to about 4 days after birth. It is rarely evident thereafter. This suggests that the binding of GBS toxin to the target endothelium occurs via specific components in the developing lung endothelial cells of the newborn that are later lost. We report here that GBS toxin can also bind to developing endothelium associated with neoplasia and induce an inflammatory response. GBS toxin was shown by immunohistochemistry to bind to capillary endothelium of human large-cell carcinomas. In nude mice bearing human tumor xenografts, intravenously administered GBS toxin caused tumor necrosis and hemorrhagic lesions, and substantially inhibited the rate of growth of the tumors. In BALB/c mice bearing Madison lung tumors, GBS toxin induced an inflammatory response resulting in marked changes in tumor morphology, including vasodilation, endothelial and tumor cell necrosis, invasion of lymphocytes and macrophages, and capillary thrombosis. In these tumor models, no evidence of toxicity to the vasculature of other tissues was observed. The reported pathophysiology of GBS in human neonates, the lack of disease in non-neonates colonized with GBS, and these results suggest that GBS toxin may have potential as a well tolerated agent in cancer therapy of some human tumors.Abbreviations GBS group BStreptococcus - PBS phosphate-buffered saline This work was supported in part by a grant from the March of Dimes Foundation  相似文献   
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