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991.
A team approach to problem solving in which a health care center and a supplier worked together to improve product quality is described and a detailed example is provided. When the health care center began using a new supplier for i.v. solutions and equipment, the supplier's incomplete product line and recurrent functional problems with products led to dissatisfaction of staff members. The supplier suggested that the health care center and supplier form a quality action team. The team addressed eight product concerns by using a total quality management process. For each concern, the team defined the problem and formulated a problem statement, collected data and determined the contributing factors to the problem, developed an action plan for solving the problem, and executed the plan and monitored its impact. After the first meeting, the team met monthly to monitor progress and discuss new ways they could work together to improve product quality and reduce costs. The implementation of the action plans allowed the health care center to realize cost savings and increased staff members' satisfaction with the supplier's products. A quality action team, composed of representatives from a health care center and one of its suppliers, used a total quality management process to solve problems to the satisfaction of both sets of participants.  相似文献   
992.
993.
The transplantation of fetal-derived hematopoietic stem cells (HSCs) may potentially be used to treat hemoglobinopathies, immunodeficiencies, and storage diseases. The levels of donor cell engraftment needed to reconstitute the recipient's hematopoietic system are disease-dependent and remain unknown for most deficiencies. We have explored the application of fetal hematopoietic stem cell transplants for the amelioration of hemolytic disease in a murine model of beta-thalassemia. Nonirradiated neonatal homozygous beta-thalassemic mice were transplanted intraperitoneally (IP) with 10(6) fetal liver cells from syngeneic nonthalassemic murine fetal donors (14 to 16 days gestation). Donor hemoglobin was demonstrated in the peripheral blood of 9 of 14 transplant recipients at levels ranging from 8.8% to 27.1% at 30 days. The levels of engraftment in 6 of these 9 transplant chimeras remained stable or increased up to 150 days after transplantation, with levels ranging from 13.6% to 54.6% at 280 days. Three chimeras have demonstrated gradually decreasing engraftment after 200 days. The degree of engraftment correlated with clinically relevant improvement: decreased reticulocyte counts (8.4% to 15.7% in chimeras [n = 9] v 17.1% to 19.1% in controls [n = 8], P = .01), increased mean RBC deformability, and the significant reduction in extramedullary hematopoiesis and iron deposits seen on histological examination of chimeric liver and spleen. These data demonstrate that fetal HSC transplants results in significant long-term chimerism with favorable alterations in red cell characteristics, and decreased hemolytic anemia in beta-thalassemia.  相似文献   
994.
995.
Velocity measurements in major blood vessels were obtained in studies of volunteers using magnetic resonance imaging (MRI) and compared with Doppler ultrasound (US). The vessels studied were the abdominal aorta, superior mesenteric artery, common carotid artery, superficial femoral artery and middle cerebral artery. Using a paired t-test, no significant difference was found between velocity values estimated by MRI and US (p > 0.08). The relative advantages of each technique in radiological practice are discussed.  相似文献   
996.
997.
Emergency air medical transport has become an integral part of the practice of medicine. In 1990, there were more than 170 air medical programs in operation in the United States. The proper and safe use of air medical transport requires a basic understanding of the medical implications of flight and the capabilities and constraints involved in transporting patients by air. The purpose of this paper is to review this information and provide guidelines for the use of air medical transport.  相似文献   
998.
Lung carbonic anhydrase (CA) permits rapid pH responses when changes in regional ventilation or perfusion alter airway and alveolar PCO2. These pH changes affect airway and vascular resistances and lung compliance to optimize the balance of regional ventilation (VA) and perfusion (Q) in the lung. To test the hypothesis that these or other CA-dependent mechanisms contribute to VA/Q matching, we administered acetazolamide (25 mg/kg intravenously) to six anesthetized and paralyzed dogs and measured VA/Q relationships before and after CA inhibition by the multiple inert gas elimination technique. Four other groups of dogs were studied to control for possible confounding effects of time under anesthesia and nonselective CA inhibition by acetazolamide: (a) saline placebo as a control for duration of anesthesia, (b) 4% CO2 inhalation to mimic systemic CO2 retention, (c) 1 mg/kg benzolamide (a selective renal CA inhibitor) or 0.5 meq/kg HCl to mimic systemic metabolic acidosis, and (d) 500 mg/kg 4,4'-dinitrostilbene-2,2'-disulfonate (an inhibitor of red cell band 3 protein) to mimic the respiratory acidosis arising from an intracapillary block to rapid mobilization of plasma HCO3- in CO2 exchange. Acetazolamide increased VA/Q mismatch and reduced arterial PO2 measured at equilibrium but these did not occur in the control group. There was no deterioration in VA/Q matching when systemic respiratory acidosis produced either by CO2 inhalation or 4,4'-dinitrostilbene-2,2'-disulfonate or metabolic acidosis (benzolamide or HCl) were imposed to mimic the effects of acetazolamide apart from its inhibition of lung CA. These results support the concept that lung CA subserves VA/Q matching in the normal lung.  相似文献   
999.
1000.
Meningeal hemangiopericytomas are rare but aggressive tumors. All eight patients in this series developed recurrences, three with distant metastases. In six patients a lytic destructive lesion of bone was evident. CT scans in three patients demonstrated diffusely enhancing lesions. No tumor calcification was present. In five of six patients angiography was characterized by multiple irregular tumor vessels, an intense prolonged blush, and the absence of early draining veins. Differentiation of these tumors from meningiomas is discussed.  相似文献   
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