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41.
Abstract. Twenty-one patients were studied at rest and during exercise after heart transplantation to compare cardiac output measured by thermodilution and impedance cardiography. Exercise was performed on a bicycle ergometer over a limited range of work load (25 and 50 watt) whilst metabolic gas exchange was recorded. One patient was studied at rest whilst his circulation was maintained by a Jarvik-7 artificial heart. The values of cardiac output measured by impedance cardiography corresponded closely with the flow rate from the artificial heart. There was also close agreement between the impedance and thermodilution measurements of cardiac output at rest and during exercise. Both measurements followed the changes in heart rate and oxygen consumption. Both thermodilution and impedance cardiography methods elicited good reproducibility of cardiac output measurements at rest and during exercise. These observations suggest that the noninvasive and continuous record of cardiac output obtained by impedance cardiography can be used for the postoperative monitoring of heart transplant recipients.  相似文献   
42.
The conversion of multiple whole blood donors to apheresis donors is a challenge since a rapidly expanding apheresis donor base could erode homologous collections. We addressed this concern with a plan to enhance apheresis recruitment as well as donations among homologous donors with types O and B blood. Focusing the donor's attention on blood type as it relates to type-specific product needs was the basis of our approach. A matrix was used to recruit the desired types for the desired procedures (whole blood, platelet/plasma apheresis). The matrix instructed donors of blood types O, A-, and B- to primarily give whole blood and to give apheresis as a secondary donation. Donors AB, A+, and B+ were primarily directed to apheresis donations, whole blood donation being secondary. A+ and O- donors only gave their secondary donation if they were at maximum donations with the primary donation. The collections by blood type in percentages for 12 months of 1992/93 for whole blood were O+ 38.9, 0- 7.3, A+ 29.5, A- 5.7, B+ 11.9, B- 2.1, AB+ 3.7, AB+ 0.7. For apheresis it was 0+ 36.2, 0- 6.7, A+ 33.0, A- 6.6, B+ 10.4, B- 1.2, AB+ 4.9, AB+ 1.0. In 1992/93, A+ and B+ apheresis collections as compared to total apheresis collections increased by 4.9% and 13.7%, respectively. For O group apheresis donations, a decrease of 2.5% was shown and A+ whole blood donations decreased by 5.35%. During the same period of time, total apheresis collections increased by 3,058 units. We demonstrated that integration of apheresis recruitment with type-specific whole blood recruitment yielded significant increases of type-specific products.  相似文献   
43.
Preventing accidental injury to young children in the home using volunteers   总被引:1,自引:0,他引:1  
Accidental injury in the home is a major cause of death andill-health among young children. Reducing home safety hazardsby the use of safety devices such as stair barriers and safetytaps has the potential to prevent home injuries. Little is knownabout levels of home safety hazards or how to encourage parentsto reduce hazards. The Safe Place Project examined parents'knowledge of home safety and the prevalence of safety hazardsin homes where there were young children. The study also evaluatedthe effectiveness of a low-cost strategy aimed at reducing homesafety hazards. The strategy used trained volunteers to providehome safety checks and tailored safety education in conjunctionwith increasing the availability of home safety devices. Onehundred and six families with young children participated inthe project. Some homes contained many hazards, with 43% ofthe sample having more than 10 home safety hazards. At follow-up,the intervention group showed a significant reduction in homehazards and a trend towards an increase in knowledge of homesafety.  相似文献   
44.
Abstract The aim of this study was to describe the periodontal conditions in 372 35–44-yr-old and 537 noninstitutionalized 65–74-yr-old Hong Kong Chinese who were examined clinically for loss of attachment, recession, probing depth, calculus, and bleeding after probing. Community Periodontal Index (CPI) data and treatment need indications were compiled from index teeth or their substitutes. The prevalence of loss of attachment varied considerably in both cohorts according to the definition of the threshold (≥6, ≥9, and ≥12 mm, respectively). The mean numbers of teeth with loss of attachment at the ≥6-mm threshold and at higher thresholds were small. In both age cohorts, about one-fifth of subjects had probing depths ≥6-mm, while al the ≥9-mm threshold only 2–3% were so affected. Although recession was an important component of loss of attachment in the younger cohort, in the older cohort the prevalence and extent of recession were greater than for probing depths at thresholds ≥4 mm. All subjects had one or more teeth with calculus, bleeding, or both, most teeth being so affected. Eighty-four of the 537 65–74-yr-old subjects were excluded either because of edentulousness or because extractions indicated for the remaining teeth would have rendered the subjects edentulous. The distribution of subjects according to their highest CPI score was remarkably similar for the two cohorts. No subjects in either age group were assessed as “healthy” (CPI code 0) or had “bleeding only” (code 1) as their highest score. While most subjects scored CPI code 2 or 3 us their highest score, only 17% of the younger and 15% of the older cohort scored Community Periodontal Index of Treatment Needs (CPITN) code 4. Differences in the mean number of sextants affected by CPI codes between the two cohorts were mainly due to a greater number of excluded sextants in the older cohort. CPI findings for 35–44-yr-olds differed little from those reported in 1984.  相似文献   
45.
整体护理改善护患关系的体会   总被引:2,自引:2,他引:0  
孟广霞 《天津护理》1998,6(4):160-161
整体护理的实施,重塑了护士的职业价值观,增加了护患之间的接触。护士能够在自己的专业范围内积极主动地解决病人的问题,挖掘了护理人员的自身潜力,加深了护患交流,使护患关系明显改善。  相似文献   
46.
We have devised assays to detect both circulating alloantibodies to platelets (indirect assay) and platelet-association IgG and IgM (direct assay) using a flow cytometric technique. A variety of patients with immune thrombocytopenia were studied. Employment of a confocal lens in the flow cytometer increased the discrimination power of the instrument. Patients with autoimmune thrombocytopenia (idiopathic thrombocytic purpura [ITP], systemic lupus erythematosus (SLE), lymphoma, leukemia, and drug-induced thrombocytopenia showed a significant increase in platelet-associated antibody. Circulating antibodies to platelets (alloantibodies) were demonstrated in cases of platelet refractoriness and neonatal isoimmune purpura. Day-today precision of the assays ranged from 3% to 6% (coefficient of variation). No interference was shown in the presence of hemoglobin (5 g/L), triglycerides (10 g/L), or polyclonal and monoclonal immunoglobulinemia (50 g/L: IgG, IgA, IgM). The sensitivity of the direct assay was 500 attograms of IgG or IgM platelet.  相似文献   
47.
The United States is one of the few economically developed nations without a national policy supporting children and their families. This paper suggests that the United States has a unique national ideology, based on the “Calvinistic Ethic,” which results in opposition to not only social programs for children and families, but to all government supported welfare programs. Such an ethic is not found in European countries. Finally, since the United States does not have a national family policy, millions of children and their families go without health care, lack social services, and suffer from inadequate economic supports.  相似文献   
48.
本文在分析黑龙江省妇幼保健机构设置现状的基础上,论述了在社会主义市场经济新形势下,妇幼保健机构发展的指导思想、模式与对策。  相似文献   
49.
One of the causes of implant failures in cemented implant-retained prostheses is the fracture of abutment screw or UCLA abutment. This article reports a case of simultaneous fracture of two UCLA abutments screws occurring in an implant-supported prosthesis placed in the mandibular molar region. The fractured structures were examined under scanning electron microscopy to investigate the probable causes of the failure, which were not related to failures on materials or fabrication of the screws, but rather were due to shear forces. The misfit in cemented prostheses may be the most likely cause of shear force generation.  相似文献   
50.
Due to recent public debate and newly imposed resident work hour restrictions, we decided to investigate the relationship of resident call status to their ambulatory patients' satisfaction. Resident continuity clinic patients were asked to rate their level of satisfaction on a 10-point Likert-type scale. Using multiple regression approaches, these data were then assessed as a function of resident call status. We found that in 646 patient encounters, patient satisfaction scores were significantly less when the resident was postcall, 8.99 ± 1.8, than when not postcall, 9.31 ± 1.3. We herein discuss etiologies and implications of these findings for both patient care and medical education.  相似文献   
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