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991.
Effect of contrast material dose on clinically evident change in renal function was studied prospectively in 200 examinations requiring intravenous or intraarterial administration of contrast material. All patients were adequately hydrated. Blood urea nitrogen and serum creatinine were measured before and after the procedure. Ionic and nonionic contrast agents were used. Total dose of contrast material ranged from 30 to 530 mL (mean, 237 mL). There was no tendency to give smaller doses to patients with preexisting renal impairment and no relationship between total dose and patient age. No consistent clinical effect on renal function was demonstrated with increasing dose, regardless of whether ionic or nonionic agents were used. In adequately hydrated low-risk patients with predominantly normal initial renal function and within the dose range studied, there does not appear to be any consistent clinical change in renal function with increasing contrast material dose. 相似文献
992.
The patients registered with a general practice are usually spread over many censusareas and overlap with the distribution of neighbouring practices, so a validated method of aggregating census data to describe the characteristics of practice patients is required. Four methods were used to provide estimates of the percentage of patients aged 75 years and over from census data for 81 practices in Suffolk, England, and these were compared with values derived from the FHSA patient register. Census values for practice areas produced better estimates than those based on the location of the surgery, but the best methods were based on patient-weighted averages of ward and enumeration district data. The finer geographical detail of enumeration districts did not produce substantially more accurate estimates than the ward-level data: both gave estimates with limits of agreement within 2% of the patient register values. Errors in the census, errors in patient registers and selective geographical distributions of practice patients prevent close matching of census and register measures, but two of the methods tested produced estimates that allow broad comparisons between practices. 相似文献
993.
Tumors of the bronchi: role of evaluation with CT 总被引:4,自引:0,他引:4
Computed tomography (CT) was performed in 142 patients thought to have an endobronchial tumor based on clinical or radiologic grounds. In 121 patients an endobronchial mass was confirmed at bronchoscopy with biopsy or at surgery. The CT scans were evaluated independently by two experienced observers (A and B). For statistical purposes the result in each single bronchus from the level of the trachea to the segmental bronchi was considered separately. A total of 361 abnormal and 1,413 normal bronchi were confirmed with bronchoscopy or surgery. Observers A and B identified 100% and 99%, respectively, of the abnormal bronchi and 97% and 96%, respectively, of the normal bronchi on CT scans. For the standard CT examination (8-mm-thick sections) a sensitivity of 94% (observer A) or 91% (observer B) and a specificity of 99% (observers A and B) were found in the diagnosis of a normal or narrowed bronchial lumen. CT proved to be a reliable method for demonstrating tumor lesions of the bronchi. 相似文献
994.
Outcome measures: problems and opportunities for public health nursing
Increasingly, outcome measures are being used to evaluate the effectiveness of health care. There are particular difficulties in establishing outcome measures for public health nursing, especially those that would demonstrate health gain. These problems arise as a result of the role of public health nursing and the nature of outcome measures. Possible solutions are the use of caseload and community profiles or the aggregation of client-negotiated health objectives. These solutions would also provide small area health information and outcome measures which would be sensitive to health needs in local communities. 相似文献
Increasingly, outcome measures are being used to evaluate the effectiveness of health care. There are particular difficulties in establishing outcome measures for public health nursing, especially those that would demonstrate health gain. These problems arise as a result of the role of public health nursing and the nature of outcome measures. Possible solutions are the use of caseload and community profiles or the aggregation of client-negotiated health objectives. These solutions would also provide small area health information and outcome measures which would be sensitive to health needs in local communities. 相似文献
995.
Jan Reed PhD RN BA Valerie Roskell Payton PhD RM MA 《Health & social care in the community》1997,5(4):261-268
This paper describes some of the findings of a study undertaken to examine the processes of adaptation that older people engage in when moving into care homes, that is nursing and residential homes. In particular, the paper presents data from resident interviews which indicate the importance of the relationships that they develop with each other, and also data from staff focus groups, which indicates that staff have a limited awareness of this. We contend that attempts to develop practice in care homes to overcome the effects of institutionalization, frequently promoted through the concept of individualized care within the context of the carer-resident relationship, could benefit from a parallel recognition of the importance of resident groups in enhancing the experience of life in care homes. In other words, just as individuals have needs, so too do the home communities of which these people are members. 相似文献
996.
Gioacchino Tedeschi Andrea Righini Alberto Bizzi Alan S. Barnett Jeffry R. Alger 《Magnetic resonance in medicine》1995,33(1):127-133
Long echo time (272 ms) 1H magnetic resonance spectro-scopic imaging was used to measure the relative magnitudes of the N-acetylaspartate (NAA) signal in a variety of anatomically defined brain structures (centrum semiovale, thalamus, medial frontal cortex, and genu of the corpus callosum) composed primarily of gray matter or white matter. Six normal young adult humans aged 30–40 were studied. With a 95% level of statistical confidence, the white matter in the centrum semiovale (CSO) produced a more intense NAA signal than did the gray matter in the thalamus and the frontal cortex. Differences between the white matter regions were also noted. The CSO white matter's NAA signal yielded a larger NAA signal than did the white matter of the genu of the corpus callosum. Possible reasons for the anatomical variation in the cerebral NAA signal intensity are discussed. 相似文献
997.
An improved technique for percutaneous placement of Greenfield filters via the femoral vein is described. The technique involves the use of an extra-long sheath for filter placement and the application of a purse-string suture at the venipuncture site to facilitate hemostasis. 相似文献
998.
The findings of a three-round Delphi survey, conducted to explore the role of the British nurse teacher as it emerges within Project 2000 programmes, are discussed The panel of experts comprising 201 grade 2 nurse teachers was drawn from the 25 of the 28 colleges in England who had implemented Project 2000 between September 1989 and April 1991 The findings highlight the complex and multifaceted role of the nurse teacher and the changes which are occurring in the role Currently, the main changes are related to teaching and learning activities These emphasize the depth, level and specialist nature of the teaching, and teaching on a variety of courses at diploma and degree level Assessment activities are given the highest overall rating as important, and recruitment activities the lowest, in both the current and future roles Educational management and administrative activities are found to be numerous and currently do not appear to be declining The few changes that have occurred to the administrative areas have been replaced with similar activities Another important area for the future was perceived to be research activity In view of the developing partnership with higher education in the United Kingdom, this is not a surprising finding 相似文献
999.
OBJECTIVES: We aimed to measure the change in prescribing of oral
contraceptives after the October 1995 UK 'pill-scare'. DESIGN: Analysis was
undertaken of an automated database of 100 general practices (372 doctors)
in England, Scotland and Wales which use the AAH Meditel computer system.
Analysis involved two stages. First, we reviewed prescribing of oral
contraceptives at three time periods: before the scare (18.10.95); the
following three months (19.10.95-18.1.96); and 3- 6 months post-scare
(19.1.96-18.4.96). Second, we examined the cohort of women on the pill at
the time of the scare to assess discontinuation rates and pill switches
after 6 months. RESULTS: Six months after the scare the proportion of women
between 16 and 50 years of age prescribed any contraceptive pill decreased
by only 3.5% (95% confidence limits: 2.2%-4.8%). The proportion of
pill-users prescribed third generation pills decreased from 53.4% to 18.1%,
while prescribing of second generation pills increased from 20.1% to 48.4%.
The proportion of women currently on third or second generation pills at
the time of the scare, who were no longer prescribed any pill after 6
months, was the same as for the equivalent period in the previous year.
CONCLUSIONS: The number of women prescribed the pill did not alter markedly
after the pill- scare. The main change was a switch from third to second
generation pill types. In any future pill-scare women should be warned
about the risk of pill-failure if the correct procedure for switching pills
is not followed.
相似文献
1000.