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Throughout most medical careers the practical aspects of dealingwith tracheostomies are an ignored but simultaneously fearedaspect of patient care. They are generally regarded as someoneelse's business, right up to the point when a disaster occurs.Even when the patient is breathless and needing help many healthpractitioners of all types fear to step in and execute  相似文献   
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BACKGROUND: The process of gastro-duodenal digestion may play a role in determining the allergenic properties of food proteins. The sensitizing and allergenic potential of digestion products of highly degraded allergens, such as the major peanut allergen Ara h 1, is currently under debate. We evaluated the effect of in vitro gastro-duodenal digestion of Ara h 1 on T cell reactivity and basophil histamine release. METHODS: An in vitro model of gastro-duodenal digestion was used to investigate changes in the allergenic properties of Ara h 1 using in vitro assays monitoring T cell reactivity (proliferation, cytokine production) and histamine release of basophils from peanut allergic individuals. The digestion process was monitored using an SDS-PAGE gel. RESULTS: In vitro gastric digestion led to rapid degradation of Ara h 1 into small fragments M(r) L5600. Gastric digestion did not affect the ability of Ara h 1 to stimulate cellular proliferation. Gastro-duodenal digestion significantly reduced its ability to stimulate clonal expansion (P<0,05; Wilxocon's signed rank test). The Th-2 type cytokine polarization of T cells from peanut allergic donors (IFN-gamma/IL-13 ratio and IFN-gamma/IL-4 ratio of CFSE(low) CD4(+) T cells) remained unchanged regardless of the level of digestion. Histamine release of basophils from peanut allergic individuals was induced to the same extent by native Ara h 1 and its digestion products. CONCLUSION: Gastro-duodenal digestion fragments of Ara h 1 retain T cell stimulatory and IgE-binding and cross-linking properties of the intact protein.  相似文献   
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This study is a retrospective review of nine patients who sustained isolated fractures of the lateral process of the talus. The majority were caused by inversion or a combination of inversion and dorsiflexion of the foot. Following a review of the literature and anatomical dissections the authors recommend a classification based on anterior-posterior tomography of the talus, into intra- and extra-articular fractures.  相似文献   
15.
In recent trials in The Gambia, mass chemoprophylaxis with Maloprim administered over several years by primary health care workers to children aged 3-59 months has reduced both mortality and morbidity without inducing impairment of natural immunity or significant development of drug resistance. Taking expenditure of both time and money, by both public authorities and village volunteers, into account, the costs and the cost effectiveness of such mass chemoprophylaxis are estimated here. The cost per child protected per season was (1990 US) $2.84; the cost per childhood death averted was $143. Both costs compare favourably with those of permethrin bed net impregnation. So in some circumstances where malaria is holoendemic, control of childhood malaria by chemoprophylaxis may be more economically efficient than provision of impregnated bed nets.  相似文献   
16.
Failure to retain health professionals in rural areas contributes to the poor health status of these communities through an inability to deliver reliable and consistent services. Considerable attention has been focused on factors affecting recruitment of health professionals. Far less is known about factors affecting the retention of occupational therapists. This was the focus of this study. Ethnographic interviews were used to explore the experiences of 10 occupational therapists who had left rural practice. Six themes emerged from the participants' experiences, from when they first considered rural practice to reflections following their departure from it. These themes were initial appeal, facing the challenge, rural practice issues, the social sphere, reasons for leaving and the value of rural experience. These factors gave rise to a proposed Model of Retention Equilibrium, which suggests that retention can be improved by addressing the imbalance between incentives to leave and incentives to stay. The model provides a useful framework for occupational therapists contemplating rural practice, as well as for health services managers responsible for service delivery in rural areas.  相似文献   
17.
OBJECTIVE: The aim of this study was to assess the severity of epilepsy and its effect on patients lives, and to describe patients' use of and attitudes to health care. METHOD: A questionnaire was sent to 595 people with epilepsy identified from 14 general practices in north-west Bristol. All patients aged 16 years and over receiving anti-epileptic medication for their epilepsy were included in the study. Areas investigated included severity of epilepsy and its effect on quality of life, anti-epileptic medication and its perceived effect, health care utilization and preferences for health care. RESULTS: Seizure frequency was strongly associated with adverse effects of epilepsy. Attacks of epilepsy were experienced at least monthly by 20.4% (95% confidence intervals (Cl) 17.0-23.7%) of patients, 29.4% (25.4-33.4%) took more than one anti-epileptic drug, 56.1% (50.1-62.2%) reported drug side effects, 74.1% (70.3-77.8%) would prefer to receive all or most of their epilepsy care in a general practice setting, and 69.8% (63.5- 76.2%) would like contact with a primary care-based epilepsy specialist nurse. During the previous year 42.4% (35.9-48.8%) of patients had not seen a doctor about their epilepsy. Of patients who had attended the general practice only 13.4% (9.6-17.2%) had regular arrangements to see their GP about epilepsy. Patients receiving both primary and secondary care had the greatest needs and wants for improved care. CONCLUSIONS: Structured care, including regular appointments, co-ordination of primary and secondary care, and increased monitoring and discussion, may improve the quality of life of people with epilepsy, but requires evaluation.   相似文献   
18.
 Accurate, timed urine collections for the measurement of glomerular filtration rate (GFR) may be impractical in infants or in patients with urological abnormalities. GFR may be measured without urine collection using a constant subcutaneous infusion of iothalamate. We compare the infusion clearance with conventional renal clearance in 14 children and young adults. The mean clearance ratio (infusion clearance/renal clearance ± 1 SD) was 0.99±0.1 and the mean discrepancy between the two methods was 8.5%±4.7%. The 95% limits of agreement for the ratio of the two methods are 0.83–1.23. These data indicate that subcutaneous infusion of iothalamate is a practical method for measuring GFR in children without a urine collection. Received March 18, 1996; received in revised form February 12, 1997; accepted March 26, 1997  相似文献   
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Winkler  ML; Olsen  WL; Mills  TC; Kaufman  L 《Radiology》1987,165(1):203-207
Two fast magnetic resonance (MR) imaging techniques, advanced Fourier and partial-flip imaging, were used at 0.35 T to examine 21 patients with suspected intracranial lesions; the results were quantitatively compared with a conventional spin-echo study. Both of the fast MR techniques yielded a fourfold reduction in imaging time per section. The advanced Fourier sequence showed contrast that was identical to the conventional spin-echo study with signal-to-noise ratios of 58% and 57% for the first and second echoes, respectively. The partial-flip sequence showed a contrast of 109% and 57% for lesions versus substantia alba, and 107% and 78% for substantia grisea versus substantia alba relative to the first and second echoes of the conventional spin-echo study. The partial-flip sequence was particularly sensitive to magnetic susceptibility; this produced artifacts that may undermine the usefulness of partial flip for routine screening in certain parts of the brain. However, this susceptibility significantly improved the detection of intracranial hemorrhage when compared with the spin-echo sequence, particularly when combined with phase mapping of the partial-flip study.  相似文献   
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