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41.
Specific hemodynamic factors have been shown to be associated with atherosclerotic plaque localization at the human carotid bifurcation. Flow field characteristics may also determine plaque distribution in the abdominal aorta. We therefore characterized flow patterns in a glass model abdominal aorta that included its major branches under conditions of steady flow. Outflow resistances of the celiac, superior mesenteric, renal, inferior mesenteric, and iliac arteries were varied to produce flow distributions consistent with rest, the postprandial state, and vigorous lower limb exercise. Flow patterns were visualized with three colors of dye injected simultaneously through capillary tubes at selected locations and recorded as still photographs and by cinephotography on videotapes. Under resting conditions a large region of flow separation and stagnation occurred at the posterior wall of the aorta directly opposite the orifices of the superior and inferior mesenteric arteries. Similar separation regions were observed during the simulated postprandial state but diminished markedly when distal outflow was increased to levels consistent with exercise. In the highly susceptible infrarenal aortic segment, beginning about 2 cm below the renal artery orifices, multiple secondary flow patterns with three to four counterrotating vortex formations were observed under both resting and postprandial conditions but disappeared in the exercise state. Secondary flow patterns were not noted in the suprarenal abdominal aorta, which is usually relatively spared. Such features have been related to plaque localization elsewhere, and the disappearance of these patterns with increased flow velocity during exercise is consistent with the previously noted protective effect of unidirectional laminar high-flow states. The beneficial effects of physical fitness programs may be related in part to these hemodynamic modifications.  相似文献   
42.
Objective To quantify the extent and types of minor ailments in children that were presented at community pharmacies and the types of over‐the‐counter (OTC) medicines purchased in response to these ailments. Method Data on all requests and sales of OTC medicines for children (aged 16 years and under) and consultations for minor ailments in children were recorded in eight community pharmacies for one week every month over a 12‐month period. Participants were members of the public who consulted the pharmacists or other pharmacy staff in the community pharmacies. Key findings A total of 976 consultations was recorded with 61.5% requesting an OTC medicine by name and 38.5% by symptom presentation. An average of 10.2 consultations was made per pharmacy per week. Requests for treatment were usually made within five days of symptom occurrence (86%). Most of the consultations were made by mothers (75%), although 17% were by fathers. The most commonly purchased OTC medicine was paracetamol. There were five requests for aspirin and one was for a 2‐year old child. A total of 62 cases (6%) was referred back to the child's primary care physician (general practitioner). Conclusions Symptoms related to cough and cold were the most common problems in children presenting to community pharmacies for treatment. Paracetamol was the most widely used OTC medicine in children. Pharmacy staff do question the request for OTC medicines such as aspirin, to ensure its safe use. Community pharmacies play an important role as the first port of call for advice on minor ailments in children and have an opportunity to provide health promotion to carers of children.  相似文献   
43.
Cisapride in the treatment of post-operative ileus   总被引:2,自引:0,他引:2  
The effect of cisapride on duration of post-operative ileus after surgery was investigated in a randomized, double-blind, placebo-controlled study. Patients undergoing elective upper gastrointestinal (n = 47) or colonic (n = 22) surgery were pre-operatively randomly allocated to treatment with either cisapride 30 mg t.d.s., by rectal administration, or placebo. Treatment started exactly 48 h after surgery if the patient at this time had not passed stool. Time to passage of first stool after surgery was estimated. Mean time to passage of stool was 85 (32) h (s.d.) for cisapride-treated and 91 (43) h for placebo-treated patients. No difference between the treatment groups was noted. Treatment with cisapride did not shorten the duration of postoperative ileus after either upper gastrointestinal or colonic surgery.  相似文献   
44.
Despite successful surgical revascularization of ischemic limbs, a local and systemic reperfusion injury may occur after normal blood reperfusion. Recent experimental and clinical application of controlled limb reperfusion in Europe has demonstrated superior results, with lower morbidity and mortality. This new surgical technique includes modification of the reperfusate (calcium, pH, substrates, osmolarity, free radical scavenger) and the circumstances of initial reperfusion (time, temperature, pressure). This report describes the first application of controlled limb reperfusion after reperfusion injury. A 16-year-old boy underwent femoral access cardiopulmonary bypass for repeat cardiac repair with an ischemic time of 245 minutes. Postoperatively, severe ischemia/reperfusion syndrome developed with muscle contracture, immobility, and anesthesia of the right leg with a second ischemic time of about 6 hours. The systemic creatine phosphokinase level was 88,000 U/L; myoglobin was 27,000 ng/mL. He underwent controlled limb reperfusion by withdrawing blood from the aorta and mixing it with a crystalloid solution (calcium-reduced, hyperosmolar, hyperglycemic, alkalotic, glutamate- and aspartate-enriched, and containing a free radical scavenger) under controlled conditions (blood:crystalloid solution 6:1, for 30 minutes, reperfusion pressure < 50 mm Hg, and normothermia) before establishing normal blood reperfusion. Metabolic data from the central and femoral vein demonstrated a significant reduction of all previous elevated enzyme levels, avoidance of hyperkalemia, normalization of acidosis, and avoidance of systemic reperfusion injury with no multiorgan failure. Limb salvage was accomplished and functional recovery almost complete. To the authors' knowledge, this is the first application of controlled limb reperfusion reported in North America. With this surgical technique we were able to prevent metabolic local and systemic reperfusion changes after prolonged ischemia and also reduced previous reperfusion changes. This report confirms former experimental data, and further clinical studies are warranted.  相似文献   
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46.
Hayden  CK  Jr; Swischuk  LE; Rytting  JE 《Radiology》1987,164(1):131-134
Among 600 infants examined with ultrasound for vomiting, seven (mean age, 3 months) had distinctive features that can be considered diagnostic of gastric ulcer. The findings are thickening of the mucosa (greater than 4 mm) in the antropyloric region, elongation of the antropyloric canal, persistent spasm, and delayed gastric emptying. Two of the infants had slight thickening of the pyloric muscle. Gastrointestinal series or endoscopy demonstrated thickened gastric mucosa and a deformed gastric antrum in all infants, as well as actual ulceration in five.  相似文献   
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49.
The pharmacology of a new pasteurized factor VIII (FVIII) concentrate derived from human blood plasma was studied in 23 adults with hemophilia A. In Part 1 of the study involving six nonbleeding subjects, the mean increase in FVIII activity was 1.43 +/- 0.34 U per ml 10 minutes after an intravenous dose of 50 U per kg. The intravascular survival kinetics in these six patients showed a biphasic decay curve with an initial mean half-life of 5.1 +/- 1.2 hours probably representing early redistribution, and a late half-life of 13.3 +/- 4.9 hours. In Part 2 of the study, the activity at 10 minutes was measured in another 17 patients, as well as in one patient already studied in Part 1. The mean increase in activity with the 24 observations was 1.13 +/- 0.37 U per ml with a mean FVIII dosage of 51.0 +/- 2.6 U per kg of body weight. Only one patient had an allergic reaction, which did not recur when the patient was given a second lot.  相似文献   
50.
Nurses are leaders in implementing innovations that can create positive outcomes in the prevention and management of pressure ulcers in patients admitted to acute care hospitals. Believing that nurses knowledgeable in best practices could impact prevalence, incidence, and care of pressure ulcers, an educational program was developed in a Canadian healthcare system to inform and empower nurses providing skin and wound care. The program afforded participants the opportunity to acquire the knowledge and skill to recognize patients at risk for developing pressure ulcers and to independently treat Stage I and Stage II pressure ulcers and skin breakdown related to moisture, friction, and shear. The program includes evidence-based practice recommendations and highlights the Best Practice Guidelines developed by the Registered Nurses Association of Ontario, a provincial body taking an active role in the development, implementation, and evaluation of published guidelines derived from global research literature synthesis. Pre- and post participation assessment of 65 nurse participants from three hospitals deemed the program successful in terms of knowledge and fulfillment of their educational expectations. Organizational support to implement the skin and wound care resource nurse role was encouraging and medical directives for Stage I and Stage II pressure ulcers by nurses were implemented. Evaluation and monitoring of program outcomes, including pressure ulcer incidence rates, continue.  相似文献   
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