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1.
Conventional risk factors have very low predictive power in identifying haemodialysis patients at high risk of vascular accidents. A role for apolipoprotein E isotypes was looked for in a small, but rigorously defined, cohort of longterm haemodialysis patients. In individuals with high vascular risk, as identified by higher common carotid intima/media thickness, we found an excess of apolipoprotein E4 alleles. This preliminary result requires confirmation in large patient cohorts.   相似文献   
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Changes in anal pressure have been monitored during the induction of anaesthesia. Falls in pressure accompany loss of consciousness following bolus doses of commonly used intravenous and inhalational anaesthetic agents. Subsequent rises in pressure towards pre-anaesthetic levels are usually associated with the time taken to correct responses and initial recovery. Premedication, including anticholinergic drugs in conventional dosage, does not affect anal pressure.  相似文献   
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Hodgkin disease: CT of the thymus   总被引:2,自引:0,他引:2  
Heron  CW; Husband  JE; Williams  MP 《Radiology》1988,167(3):647-651
The computed tomography (CT) scans in two groups of patients with Hodgkin disease were reviewed to determine the frequency of thymic enlargement. In 50 CT scans from 50 patients with evidence of thoracic disease on CT scans who were examined for primary staging, the thymus was enlarged in 15 of 50 (30%). Fifty CT scans were obtained from 44 patients at the time of 50 separate episodes of known or suspected relapse. Relapse occurred in the mediastinum in 12 episodes, lung parenchyma in five, and both sites in one. Thymic enlargement thought to be due to involvement by disease was present in seven of 18 (38%). Mediastinal disease was associated with thymic enlargement in all but one patient in whom a thymic cyst developed after radiation therapy. Differentiation of thymic enlargement from enlarged superior mediastinal lymph nodes was easily made in all but two patients. Thymic enlargement in the absence of lymph node enlargement may indicate a different disease, since isolated Hodgkin disease of the thymus is uncommon. Primary thymic tumor should be considered initially, whereas after treatment, rebound hyperplasia of the thymus may be the cause of enlargement.  相似文献   
6.
Solitary bronchioloalveolar carcinoma: CT criteria   总被引:14,自引:0,他引:14  
The computed tomographic (CT) scans of 30 patients with solitary bronchioloalveolar carcinoma were reviewed. Common features at CT included the peripheral or subpleural location of a pulmonary mass (25 cases), pseudocavitation (18 cases), heterogeneous attenuation (17 cases), irregular margins forming a star pattern (22 cases), and pleural tags (21 cases). Using these CT criteria, four independent observers attempted to identify cases of bronchioloalveolar carcinoma from a larger sample of lung cancers and benign lesions by categorizing a series of test cases into four probability categories. Although the bronchioloalveolar carcinomas were correctly ranked in the two highest probability categories 75% of the time (in 45 of 60 cases), there was considerable overlap with other lung lesions, particularly with adenocarcinoma and large cell undifferentiated carcinoma. However, even though the typical features of bronchioloalveolar carcinoma are not invariable or highly specific, they are characteristic enough to suggest the diagnosis.  相似文献   
7.
Cricket fast bowlers are the potent strike force in a multidiscipline team. They subject their spines to repetitive sagittal plane and rotatory movements over many years. The effect of this repetitive stress has not previously been analysed. This study examined 20 former fast bowlers to determine the incidence of spondylolysis, spondylolisthesis and degenerative change. Fast bowlers are noted to have an increased incidence of spondylolysis. A mixed front/side bowling style involving more lumbar hyperextension or rotation has significant association with spondylolysis when compared with side-on bowling styles. There was a high incidence of radiological thoracolumbar degenerative facet joint and disc disease in former fast bowlers.  相似文献   
8.
An established chemical faecal occult blood test (Haemoccult prepared without rehydration) has been compared with a new immunological test (Hemeselect) in patients referred for investigation of lower gastro-intestinal symptoms. Hemeselect was shown to have a higher sensitivity for colorectal carcinoma (94.0% compared with 58.0%), the greatest difference in sensitivity between the two tests being for rectal cancers. Similarly Hemeselect was more sensitive than Haemoccult for colorectal adenomas (66.6% vs 33.3%), and for inflammatory bowel disease (88.9% vs 33.3%). However the enhanced sensitivity of Hemeselect for colorectal neoplasia and inflammatory bowel disease was accompanied by a significant increase in the overall rate of positive reactions (32.8% of patients had a positive Hemeselect reaction compared with 14.8% who had a positive Haemoccult test), and a reduction in specificity (84.1% for Hemeselect vs 96.0% for Haemoccult). Hemeselect is a more sensitive indicator of colorectal neoplasia in symptomatic subjects, trials of its use as a screening test for asymptomatic neoplasia appear justified.  相似文献   
9.
OBJECTIVE: The aim was to establish the potential efficacy, tolerabilityand side-effect profile of electromagnetic therapy as an adjunctto conventional dressings in the treatment of venous leg ulcers. METHOD: A prospective, randomized, double blind controlled clinicaltrial was carried out in a dedicated leg ulcer clinic basedin one urban general practice. Nineteen patients with leg ulcersof confirmed venous aetiology were assessed. The main outcomemeasures were rate and scale of venous leg ulcer healing, changesin patient-reported pain levels, quality of life, degree ofmobility, side effect profile and acceptability to patientsand staff. RESULTS: Sixty-eight per cent of patients attending this dedicated clinicachieved improvements in the size of their ulcer (4, 21%, healedfully) and in reduced pain levels (P < 0.05) during the trial,despite the chronicity of ulcer histories. Patients treatedwith electromagnetic therapy at 800 Hz were found at day 50to have significantly greater healing (P < 0.05) and paincontrol (P < 0.05) than placebo therapy or treatment with600 Hz. All patients reported improved mobility at the end ofthe study. The electromagnetic therapy was well tolerated bypatients, with no differences between groups in reporting adverseevents, and proved acceptable to staff. CONCLUSION: Despite the small numbers in this pilot study, electromagnetictherapy provided significant gains in the healing of venousleg ulcers and reduction in pain. Keywords. Electromagnetic therapy, RCT, leg ulcers, primary care.  相似文献   
10.
The increasing interest in 5-fluorouracil (5-FU) modulation and the development of new antifolates has focused attention in recent studies on the expression of the target enzyme thymidylate synthase (TS) as a determinant of drug sensitivity and resistance. Resistance to TS-directed drugs has been shown to occur in vitro and in vivo with increased expression of the enzyme (determined by enzymatic assays as well as protein and gene expression assays). Several studies have evaluated the role of TS as a prognostic indicator of clinical response to chemotherapy containing TS-directed drugs. We have used a polyclonal antibody to recombinant human TS to establish a silver-enhanced immunogold staining method to localize TS in human tumours. Human tumour cell lines with acquired resistance to TS inhibitors owing to increased levels of TS were used to confirm the specificity of immunostaining. Stained sections were evaluated by image analysis. Immunostaining in tumour sections was greatly reduced (>80%) by preabsorption of the antiserum with recombinant TS. The method was used to determine the extent of TS immunostaining in 134 primary human colorectal tumours. The results were then compared with the clinical outcome and response to chemotherapy for the treatment of subsequent metastatic disease. A wide range (approximately 100-fold) of TS immunostaining was observed in these primary tumour sections. Normal mucosal tissue levels were 5-10 times lower than those observed in the adjacent tumour tissue. The values for TS immunostaining did not correlate with clinical endpoints, such as time from diagnosis to relapse, response to chemotherapy for disseminated disease, nor with Dukes'' staging. This lack of correlation may be because this group of patients was selected on the basis of their need for palliative chemotherapy and did not include patients who were cured of their disease. Also, primary tumour TS expression may not give a good indication of the TS expression in metastatic lesions. The prognostic significance of TS protein expression in primary and metastatic lesions requires further evaluation.  相似文献   
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