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排序方式: 共有757条查询结果,搜索用时 31 毫秒
71.
Gloria S‐C Yuen BEng MBiomedEng Alistair B Sproul BSc PhD 《Clinical & experimental optometry》2010,93(2):66-76
Background: Compact fluorescent lamps (CFLs) have been heralded as highly energy efficient replacements for incandescent light globes, however, there is some public dissatisfaction with the light output and colour of CFLs. Independent examination of the claims made has not been made. Compliance with the interim Australian/New Zealand Standard has not been established by any independent authority. While the total light output (luminous flux) may meet certain standards, luminous intensity distributions of some designs do differ significantly from the incandescent sources that they are intended to replace. Methods: Luminous intensity distribution, luminous flux and spectral energy distribution of CFLs claimed to be equivalent to 75 W incandescent globes and 75 W incandescent globes (pearl and clear) were measured. Luminous flux, luminous efficacy, colour rendering index, correlated colour temperature, wattage and power factor were then calculated and compared with claims made by manufacturers and requirements of the standards. Results: The sources generally complied with the requirements for luminous flux, luminous efficacy, colour rendering index and correlated colour temperature. The claim of 75 W equivalence, which is not regulated in Australia and New Zealand, is justified less than half the time. Luminous intensity distributions of biaxial CFLs are distinctly different from the incandescent lamps they purport to replace. Conclusion: CFLs generally comply with the standards set. The basis on which equivalent wattages are claimed needs to be included in the Australian and New Zealand standard because this is the measure most likely to be relied on by the public. Due to the differences in luminous intensity distribution, CFLs may not necessarily be a direct replacement for incandescent sources without some consideration. 相似文献
72.
The sonographic examinations of four patients with simple ectopic ureters and 11 with ectopic ureteroceles were reviewed to determine distinguishing characteristics. Ectopic ureters, in cases of extreme dilatation and tortuosity, sometimes mimic multiseptated, cystic abdominal masses. However, the proximal portions of some severely dilated ureters are surprisingly small. Ectopic ureters sometimes indent the lower vesical wall, simulating a ureterocele. Ectopic ureteroceles are dynamic structures, changing in shape and size according to intravesical pressure. The lower pole of a duplex kidney may be difficult to detect because of displacement by the dilated upper renal pelvis and ureter. The renal parenchyma associated with an ectopic ureter may be equally difficult or impossible to find because of diminutive dysplasia or, less commonly, acquired atrophy. Dysplasia is characterized sonographically by highly echogenic parenchyma, lack of corticomedullary differentiation, and occasionally massive enlargement by cysts. Ectopic ureters and ureteroceles can be identified by fetal sonography. 相似文献
73.
Osteomyelitis: detection with US 总被引:2,自引:0,他引:2
To evaluate the role of ultrasound (US) in the detection of osteomyelitis, the authors prospectively studied 48 patients clinically suspected of having osteomyelitis. A sonographic diagnosis was made if fluid was seen directly in contact with bone, without intervening soft tissues. Twelve of the 48 patients were subsequently found to have osteomyelitis. In 10 of them, US demonstrated abnormal fluid adjacent to the bone. This fluid was thought to represent an inflammatory exudate dissecting in a subperiosteal and/or extraperiosteal location. Eight of the 48 patients had soft-tissue fluid collections. The rest of the patients either had no abnormalities or had cellulitis. The authors conclude that US can be useful in the detection of osteomyelitis. 相似文献
74.
Growth hormone therapy for protein catabolism 总被引:5,自引:0,他引:5
GH and IGF-I have shown remarkable consistency of effect in a wide range of
catabolic conditions. Doses of around 10 IU/m2/day of GH and 80
micrograms/kg/day of IGF-I over short periods of time can improve net
protein synthesis and preserve lean body mass. Most studies have reported
metabolic endpoints, but favorable clinical effects have included decreased
hospital stay and mortality in burns, improved respiratory muscle function
in COAD, preserved grip strength post- operatively, and improvements in
cardiac and bowel failure. Adverse effects of GH treatment are uncommon and
usually related to glycaemic control. GH and IGF-I have differential
effects on insulin concentrations--increasing or decreasing concentrations,
respectively. The hypoglycaemic effects of IGF-I are dependent on route of
administration and are avoided by subcutaneous delivery. Occasional
patients have needed to discontinue GH treatment due to hyperglycaemia,
although the anabolic action of GH may be partially mediated by increased
insulin levels. The co-administration of GH and IGF-I has theoretical
advantages by both increasing IGF binding-protein concentrations and
balancing glycaemic control. An initial study with combination therapy in
calorically-restricted volunteers has shown anabolic effects greater than
with either agent alone. This approach requires further study in catabolic
patients. There is a need for large, well-designed trials with clinical
rather than purely metabolic end-points, and some of these are already
underway. Should these studies confirm the early findings, financial
considerations will become paramount, although it remains possible that
treatment may be self-financing if lengths of hospital admissions are
shortened.
相似文献
75.
LP Ham F Andrasik RC Packard CM Bundrick 《Cephalalgia : an international journal of headache》1994,14(2):118-126
In this study, the psychological functioning of patients with chronic post-traumatic headache (PTH), chronic combination headache and chronic low back pain without headache, whose time of onset was similar, and a matched group of controls was investigated. The Symptom Checklist 90-Revised (SCL-90-R), State-Trait Anger Expression Inventory (STAXI), State-Trait Anxiety Inventory, Form Y (STAI-Y), and Beck Depression Inventory (BDI) were used to assess the degree of psychopathology. A MANOVA test indicated highly significant differences between groups. In general, the pain groups fell along a continuum with PTH subjects demonstrating the highest elevations, back pain subjects demonstrating the next highest elevations, and combination subjects demonstrating fewer elevations. A cluster analysis indicated that findings were best classified into four clusters, but no one pain diagnosis predominated in any cluster. Eighty-nine percent of controls were assigned to clusters 1 or 2, which revealed essentially normal scores on all tests. It is suggested that while chronic pain patients demonstrate more psychopathology than non-pain controls, a variety of coping styles exists within each pain group independent of diagnostic categorization. 相似文献
76.
RC Cook MBChB J Zachariah MB BS F Cree BSc HE Harrison PhD 《International journal of clinical practice》1996,50(3):125-128
SUMMARY A new amoxycillin/clavulanate regimen (‘Augmentin-Duo’ 400/57), to be given orally in two divided doses, has been proposed to overcome the inconvenience of tid dosing. This observer-blind, multicentre study randomised children aged two to 12 years with lower respiratory tract infection to seven days' treatment with either amoxycillin/clavulanate bid at a dose of 25/3.6mg/kg/day (221 patients) or the currently prescribed amoxycillin/clavulanate regimen of 20/5mg/kg/day tid (216 patients). Clinical success (cure) rates at follow up were 81.0% for the bid group and 77.8% for the tid group [difference 3.2%; 95% CI (-4.36, 10.80)], indicating that the regimens were of equivalent efficacy. Both regimens were well tolerated, and there was no statistically significant difference in the incidence of adverse experiences between the two groups. Compliance with study medication was high and similar for both groups (80% compliance: bid 90.0%; tid 87.0%). 相似文献
77.
78.
Continuous Cardiac Monitoring around Atrial Fibrillation Ablation: Insights on Clinical Classifications and End Points
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79.
Background
Noise exposure is an inherent part of duty of the aircrew and maintenance staff in the Indian Air Force (IAF). An audiometric survey of IAF personnel was carried out to analyze the prevalence and severity of noise induced hearing loss (NIHL).Methods
An audiometric study of 1000 IAF personnel of various trades, age and exposure groups were carried out at an operational base. Age related correction of 5 dB per decade was applied for personnel above SO years of age. Personal factors like smoking, blood group and use of ear defenders were analysed for their effect on the prevalence of NIHL.Result
The study revealed an overall incidence of NIHL of 22.9 % in the personnel with a higher prevalence among the technical trades (26.18 %) as compared to non technical trades (12.5 %). There was a significant increase in prevalence of hearing loss with duration of exposure with 50.8% of personnel above 30 years of exposure having hearing loss. A higher incidence of hearing loss was observed in personnel of blood group O and smokers whereas use of ear defenders was protective.Conclusion
The study reveals a significantly increased prevalence of NIHL among the technical trades of the IAF personnel. The deleterious effects of smoking and protective effect of regular use of ear defenders are emphasized.Key Words: Noise induced hearing loss, Smoking, Ear defenders 相似文献80.
Stephen RC Howie Sarah Hill Augustine Ebonyi Gautam Krishnan Ousman Njie Momodou Sanneh Mariatou Jallow Warren Stevens Kevin Taylor Martin W Weber Pamela Collier Njai Mary Tapgun Tumani Corrah Kim Mulholland David Peel Malick Njie Philip C Hill Richard A Adegbola 《Bulletin of the World Health Organization》2009,87(10):763-771