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61.
We have investigated contamination of extradural catheters during normal handling with starch powdered gloves. In the laboratory, extradural catheters were handled in sterile fields with both powdered and non-powdered gloves, simulating preparation for patient insertion. The catheters together with glove samples were then examined using a Zeiss 940 scanning electron microscope. Microscopy of samples revealed starch contamination of the catheters handled with powdered gloves, especially in the side hole areas. We conclude that extradural catheters may be contaminated easily by starch powder from surgical gloves. This powder may then be deposited into the extradural space. The effect of starch in the extradural space is not known but starch is known to cause inflammatory and granulomatous reactions in other parts of the body as well as being directly allergenic. Powder contamination of catheters may be avoided easily by the use of powder-free gloves and we feel that these should be used whenever possible.   相似文献   
62.
The Australian Leukaemia Study Group myeloma study (MM1) aimed to determine the prognostic significance of clinical and immunophenotypic markers in patients with multiple myeloma. All patients were treated with standard dose melphalan and prednisone. Seventy-four patients were entered and the median survival was 27 months. Serum beta 2-microglobulin (βM) and albumin levels were the only significant clinical factors influencing survival (p = 0.007 and p = 0.008, respectively). Patients with raised levels of CD38+ lymphocytes at presentation had a significantly shorter survival than patients with normal levels (p = 0.01, logrank test, median 19 months vs 33 months). CD38 antigen expression was independent of β2M but patients with raised levels of CD38 had significantly lower levels of albumin than patients with normal levels (p = 0.001) which may explain their poorer survival. Salmon and Durie stage was not associated with antigen expression. No other B-cell antigens (CD10, CD19, CD20, CD21, CD22, CD23, FMC1 or FMC7) or plasma cell antigens tested (PCA-1) were found to be associated with prognosis. Patients who achieved plateau phase had a better prognosis than those who did not (p = 0.04 in a landmark analysis). Patients who achieved plateau phase following an objective response appeared to have a better prognosis than those who were in plateau phase at presentation (p = 0.09 in a landmark analysis). Light chain isotype suppression (LCIS) was not associated with a significant survival advantage and did not correlate with any known prognostic indicator. We conclude that phenotypic analysis of peripheral blood lymphocytes for CD38 antigen at diagnosis may be useful as a prognostic indicator in patients with myeloma.  相似文献   
63.
STUDY OBJECTIVE: To identify factors associated with smoking behaviour in primary school children in Hong Kong. DESIGN: A cross sectional survey in which both children and parents completed questionnaires. The main outcome measure was the smoking status of the children; and risk factors (knowledge of and attitude to smoking and demographic and socioeconomic background) were identified as predictors of ever/never smoking. SETTING AND SUBJECTS: Altogether 9598 primary school children, aged 8-13 years, and attending 27 schools from two districts in Hong Kong participated. MAIN RESULTS: The prevalence of ever-smoking was 12% (1119)-15% (760) in boys and 7% (359) in girls. It ranged from 3% in 8 year old girls to 52% in 13 year old boys. The factors associated with ever-smoking included the following: being a boy (adjusted odds ratio 2.21; 95% confidence interval 1.89, 2.59), increasing age per year (1.48; 1.40, 1.57), living in Kwai Tsing district (1.29; 1.10, 1.50), having one or more smokers at home (2.07; 1.78, 2.39), and having a father who was not working (1.41; 1.19, 1.67). Children who were ever-smokers had both seen and approved of their friends' smoking (8.79; 5.33, 14.50), had a more positive attitude towards smoking (3.35; 2.21, 5.09), and were more successful in recognising cigarette brand names and logos (1.67; 1.42, 1.96), but they lacked confidence (1.78; 1.32, 2.39). CONCLUSIONS: The influences on child smoking are multifactorial and programmes in Hong Kong are falling to curb them. The control of these risk factors must be incorporated in the smoking prevention policy of Hong Kong and supported by future enforced legislation.  相似文献   
64.
A 45-year-old man with neurofibromatosis presented with recurrent seizures due to hypoglycaemia caused by an insulinoma. The attacks were abolished after the successful removal of the insulinoma. This probably represents another example of the association between neurofibromatosis and a tumour consisting of cells with amine-precursor-uptake and decarboxylation.  相似文献   
65.
The newborn has a repertoire of oral zone reflexes which are intimately involved with experiences and expressions related to distress and pleasure. These help develop signaling which leads to relief of distress. The signaling involves bicycling of all limbs, with facial and vocal accompaniments, and thus the locomotor apparatus is intimately related to the oral zone reflexes. From these observations, it is hypothesized that trauma to oral zone reflexes would cause interference with the development of locomotion, initiation efforts, affect and attachment. These disturbances may be seen in different degrees in various deprivation states.  相似文献   
66.
The productivity loss in India due to deformity from leprosy was assessed in a random sample of 550 leprosy patients from a rural and an urban area in the state of Tamil Nadu. Logistic and log-linear regression analyses on these leprosy patients showed that elimination of deformity would: a) raise the probability of gainful employment from 42.2% to 77.6%; b) increase annual earnings per patient gainfully employed from Rs 2948 to Rs 6469; and c) raise overall earnings for all patients from Rs 1259 to Rs 5023 per year. The earnings of 550 control subjects (adult family members of the leprosy patients) were consistent with these predictions. Extrapolation to all of India's estimated 645,000 leprosy patients with deformity suggests that elimination of deformity would raise productivity by +130 million per year. The authors conclude that the development and evaluation of programs to eliminate deformity from leprosy deserve high priority.  相似文献   
67.
A problem of current MRA techniques is the inability to accurately depict the vascular anatomy, particularly in areas of disturbed flow. Various reasons, such as intravoxel phase dispersion, saturation, temporal variations, and maximum intensity projection (MIP) nonlinearity, cause a wrong delineation of vessel boundaries. A phase contrast (PC)-based postprocessing operation, the phase derivative (PhD), is introduced to detect phase fluctuations indicating flow. Two-dimensional and three-dimensional angiographic reconstruction algorithms are presented. Mathematical formulas are derived to predict the effect of sampling to flow profiles and the effect on the PhD of these profiles. Numerical, phantom, and preliminary in vivo experiments demonstrate that PhD images do not suffer from phase wraps and allow a velocity dynamic range extension only limited by a differential phase change. It is also shown that PhD MIPs produce higher signal-to-noise ratios than conventional PC angiograms and give a better impression of the anatomy of (stenotic) vessels and of their diameters for both laminar and disturbed flow.  相似文献   
68.
The purpose of this investigation was to determine differences in tissue composition of symptomatic and asymptomatic disc herniations as reflected in T1 and T2 relaxation times (quantitative magnetic resonance investigation of the lumber spine. The longitudinal and transverse magnetic rlaxation times (T1 and T2, respectively) were calculated from a set of 20 images obtained with five single-slice/multi-echo sequences at different repetition time values on a commercial whole-body system (1.5 T). Twenty-two symptomatic and asymptomatic disc herniations could be matched according to age, gender, disc level, and the extent of herniation (protrusion or extrusion) and were compared with regard to T1 and T2 relaxation times. Symptomatic disc herniations exhibited significantly (pT1 < 0.04 and pT2 < 0.003) shorter T1(ΔT1:–182.1 milliseconds, ?15%) and T2(ΔT2: ?11.0 milliseconds, ?21%) relaxation times than matched asymptomatic herniations. Symptomatic disc herniations also exhibited more advanced disc degeneration as graded by Pearce's criteria (p < 0.01). These results suggest that symptomatic and morphologically matched asymptomatic disc herniations differ with regard to disc matrix composition.  相似文献   
69.
An evaluation of routine operative cholangiography   总被引:1,自引:0,他引:1  
The value of routine use of operative cholangiography was evaluated in 225 patients. In 65 patients (29%), there was one or more clinical or operative indications for common duct exploration and only 21 cases showed positive cholangiographic findings and were explored. There were four negative explorations in this group. In the remaining 160 patients who had no indication for common duct exploration, 157 had a normal cholangiogram and three had false positive cholangiographic findings and were explored unnecessarily. If operative cholangiography had been performed only on those patients with clinical or operative indications for common duct exploration, no ductal stone would have been missed. A selective use of operative cholangiography is advocated and the investigation should be restricted to those patients with clinical or operative indications for exploration of the common bile-duct.  相似文献   
70.
IgA nephropathy associated with sarcoidosis   总被引:1,自引:0,他引:1  
  相似文献   
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