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21.
C. C. Yu D. A. Levison J. A. Dunn L. C. Ward M. Demonakou W. H. Allum M. T. Hallisey 《British journal of cancer》1995,71(5):1106-1110
The second British Stomach Cancer Group trial was a prospective randomised controlled trial of adjuvant radiotherapy or cytotoxic chemotherapy after gastrectomy for adenocarcinoma. It recruited between 1981 and 1986. No survival advantage has been demonstrated for the patients receiving either type of adjuvant therapy compared with those undergoing surgery alone. We report on 436 patients randomised into the trial together with 203 patients, who did not fulfil the trial criteria, referred to the trial. A univariate (log-rank) analysis of pathological factors obtained from the local referring centres showed that tumour size, macroscopic type, number os sites involved, depth of invasion, involvement of resection lines and lymph nodes and histological grade were significant determinants of survival. Histological review by two experienced histopathologists found that the Lauren classification and histological grade, but not the Ming classification, were significant prognostic factors. The degree of lymphocytic and eosinophilic infiltration and presence of dysplasia assessed by one of the pathologists showed a significant correlation with survival. However, inter-observer correlation for these histological parameters and grade was poor. Multivariate analysis identified only depth of invasion, resection line and nodal involvement as significant independent pathological variables influencing survival. This study confirms the need for expert preparation of the resected specimen to obtain the important information on depth of invasion and nodal status and also reveals some variation in histological assessment, particularly grading, in gastric carcinoma. 相似文献
22.
AM Cotterill WH Majrowski S Hearn S Jenkins MA Preece MO Savage 《Archives of disease in childhood》1996,74(5):452-454
The UK 1990 height charts are derived from an up to date dataset and introduce a change in the centile lines, particularly the addition of the 0.4th centile. This study examined the likely impact of these changes. Height data from London school children (1990-1993) were examined using Tanner and Whitehouse (TW) and UK 1990 charts. Numbers of children with height below TW 3rd centile were compared with numbers below the UK 1990 3rd and 0.4th centiles. The TW charts identified only 1% of children below the TW 3rd centile, while the UK 1990 charts identified 3% below the 3rd and 0.4% below the 0.4th centiles. If the 3rd centile remains as the referral 'cut off' for short stature, the introduction of the UK 1990 charts would increase current workload two- to three-fold, while a change to the 0.4th centile would reduce it by 50%. A significant number of children with abnormalities may be excluded from further assessment as a result of this latter change. In this small scale community study it is not possible to assess the consequences of this change. The heights at diagnosis of children with growth hormone (GH) deficiency (peak GH < 20 mU/l during a standard provocation test) were therefore compared to the 0.4th centile (UK 1990 charts). Sixty eight children with heights < 2nd centile (UK 1990 charts) currently receiving GH replacement (17 female, 51 male, aged 9.7, SD 3.5, years) were assessed, and of these, 28 (41%) had heights at diagnosis between 0.4th and 2nd centile, with a mean height standard deviation score of -2.32 (SD 0.21). This suggests that if the 0.4th centile were to be used as the sole criterion for referral for slow growth, a significant proportion of children with abnormality would not be referred for further assessment. The UK 1990 2nd centile should replace the TW 3rd centile. Children below this should undergo an intermediary medical assessment to confirm height measurement, to exclude from referral children with mild familial short stature and to identify concerns regarding the child. 相似文献
23.
Forty one (1%) of 4000 children referred for respiratory disease had chronic suppurative lung disease not due to cystic fibrosis. Further investigations showed congenital malformations in six (15%), primary ciliary dyskinesia syndrome in seven (17%), 11 had immunological abnormalities (27%), and two bronchiectasis due to aspiration (5%). Therefore the underlying cause for the disease was found in 63%. Identification of predisposing causes may facilitate prevention of further bronchial damage. 相似文献
24.
The programming of a cochlear implant speech processor used by young children is often difficult, especially when the stimulus level associated with maximum auditory loudness (MAL) needs to be determined. Excessively high stimulation should be avoided as this can have a traumatic effect. The aim of this study was to determine if a relationship exists between the intraoperatively determined electrical stapedius reflex threshold (ESRT) and the postoperatively determined MAL and hearing threshold for 27 patients, each having one of three implant types. The question of whether the ESRT provides a practical technique to simplify, improve and accelerate speech processor programming was investigated. For the monopolar stimulation mode used for the Med-El and Clarion implant systems, the average MAL and threshold was expressed as a percentage of the average ESRT across all electrodes. For the "common ground" stimulation mode used for the Nucleus implant system, a parabolic transformation was used to relate MAL and ESRT to one another. These transformations between MAL values calculated from the ESRT and the actual MAL values, determined psychoacoustically, diverged considerably from one another. Therefore, it was not possible to determine the MAL from the ESRT with certainty. The ESRT does, however, provide a means to estimate an approximate upper boundary for the MAL, apart from its use to control implant function. The determination of the exact MAL will still need to be determined using behavioural techniques. 相似文献
25.
Templeton AW; Johnson JA; Anderson WH; Cook LT; Dwyer SJ d; Preston DF; Lee KR; Rosenthal SJ; Batnitzky S; Levine E 《Radiology》1984,151(2):527-528
The increasing use of digitally formatted imaging systems requires high-quality interactive gray-scale computer raster graphics systems for the management, display, and analog film recording of digital image and alphanumeric information. These systems are a combination of computer hardware and software and implement a set of graphics protocols. This paper describes a set of interactive graphics protocols that has been developed for clinical use. 相似文献
26.
27.
A radiographic study of the ligamentous anatomy of the ankle 总被引:1,自引:0,他引:1
28.
Allum W Aminu J Bloomfield TH Davies C Scales AH Vere DW 《British journal of clinical pharmacology》1974,1(1):51-57
1 The interaction between phenylephrine and debrisoquine was studied using normal and hypertensive human volunteers, measuring blood pressure, pulse rate and pupil diameter. Single doses of phenylephrine were given before, during and after a short course of debrisoquine treatment.
2 The circulatory effects of phenylephrine are potentiated by debrisoquine; in a few subjects this potentiation was marked and a potential hazard.
3 Limited deductions could be made about the effects of debrisoquine on baroceptor responses and adrenergic mechanisms.
相似文献29.
30.
Influence of postural anxiety on postural reactions to multi-directional surface rotations 总被引:5,自引:0,他引:5
Previous studies have shown significant effects of increased postural anxiety in healthy young individuals when standing quietly or performing voluntary postural tasks. However, little is known about the influence of anxiety on reactive postural control. The present study examined how increased postural anxiety influenced postural reactions to unexpected surface rotations in multiple directions. Ten healthy young adults (mean age: 25.5 yr, range: 22-27 yr) were required to recover from unexpected rotations of the support surface (7.5 degrees amplitude, 50 degrees/s velocity) delivered in six different directions while standing in a low postural threat (surface height: 60 cm above ground) or high postural threat (surface height: 160 cm above ground) condition. Electromyographic data from 12 different postural leg, hip, and trunk muscles was collected simultaneously. Full body kinematic data were also used to determine total body center of mass (COM) and segment displacements. Four distinct changes were observed with increased postural anxiety: increased amplitude in balance-correcting responses (120-220 ms) in all leg, trunk, and arm muscles; decreased onset latency of deltoid responses; reduced magnitude of COM displacement; and reduced angular displacement of leg, pelvis, and trunk. These observations suggest that changes in dynamic postural responses with increased anxiety are mediated by alterations in neuro-muscular control mechanisms and thus may contribute significantly to the pathophysiology of balance deficits associated with aging or neurological disease. 相似文献