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91.
92.
The value of ultrasound in the diagnosis of a large rapidly growing thyroid mass was assessed in a study of 42 patients with a large (> 3 cm) rapidly growing (< two months) solitary mass. Haemorrhage into a thyroid nodule was present in 31 patients and thyroid malignancy in 11. Ultrasound of haemorrhage into a thyroid nodule revealed a large cystic mass in all 31 patients containing internal debris (22), septations (three), or a combination of both (six). The malignant causes of a large rapidly growing mass were lymphoma (two), anaplastic carcinoma (four) and metastasis (five). Ultrasound of these thyroid malignancies revealed a mass with a smooth, well-defined margin and strikingly low homogeneous echogenicity in all cases. Patients with thyroid metastases had evidence of widespread metastatic disease elsewhere. Lymphoma was differentiated from anaplastic carcinoma on fine-needle aspiration cytology or surgical biopsy. Ultrasound was of value in differentiating between a benign haemorrhagic nodule and a malignant tumour. The various malignant tumours had similar appearances, however, and could not be distinguished on ultrasound. 相似文献
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Emergency physicians and sexual involvement with patients: an Ontario survey 总被引:2,自引:1,他引:1 下载免费PDF全文
OBJECTIVE: To describe Ontario emergency physicians' knowledge of colleagues' sexual involvement with patients and former patients, their own personal experience of such involvement, and their attitudes toward postvisit relationships. DESIGN: Mailed survey. SETTING: Ontario. PARTICIPANTS: Emergency physicians practising in Ontario. RESULTS: Of 974 eligible mailed surveys, 599 (61.5%) were returned. Of these respondents, 52 (8.7%) reported being aware of a colleague in emergency practice who had been sexually involved with a patient or former patient. When describing their own behaviour, 37 respondents (6.2%) reported sexual involvement with a former patient. However, of this group, only 9 (25.0%) had met the patient in an emergency department. Thus, of the total number of respondents, only 1.5% (9/599) reported sexual involvement arising out of an emergency department visit. Most respondents (82.4%) agreed that it is inappropriate behaviour to ask a patient for a date after an emergency assessment and before the patient's departure, and 66.4% felt that it is inappropriate to contact the patient after discharge. However, only 10.6% believed it to be unacceptable to request a social meeting after encountering a patient previously cared for in the emergency department in a nonprofessional setting. Most respondents (96.5%) did not believe that sexual involvement could ever be therapeutic for the patient. However, only 66% felt that it was always an abuse of power and 62.4% supported zero tolerance of all sexual involvement between physicians and patients. CONCLUSIONS: Vague regulatory guidelines currently in place have failed to dispel confusion regarding what is acceptable social behaviour for physicians providing emergency care. Our results support the need for clarification, and suggest a basis for guidelines that would be acceptable to the emergency medical community: that an emergency visit should not form the basis for the initiation of personal or sexual relationships, yet neither should it preclude their development in nonmedical settings. 相似文献
96.
The effect of outdoor fungal spore concentrations on daily asthma severity. 总被引:10,自引:2,他引:8 下载免费PDF全文
R J Delfino R S Zeiger J M Seltzer D H Street R M Matteucci P R Anderson P Koutrakis 《Environmental health perspectives》1997,105(6):622-635
The relationship between day-to-day changes in asthma severity and combined exposures to community air pollutants and aeroallergens remains to be clearly defined. We examined the effects of outdoor air pollutants, fungi, and pollen on asthma. Twenty-two asthmatics ages 9-46 years were followed for 8 weeks (9 May-3 July 1994) in a semirural Southern California community around the air inversion base elevation (1,200 ft). Daily diary responses included asthma symptom severity (6 levels), morning and evening peak expiratory flow rates (PEFR), and as-needed beta-agonist inhaler use. Exposures included 24-hr outdoor concentrations of fungi, pollen, and particulate matter with a diameter < 10 microns (PM10; maximum = 51 micrograms/m3) and 12-hour day-time personal ozone (O3) measurements (90th percentile = 38 ppb). Random effects longitudinal regression models controlled for autocorrelation and weather. Higher temperatures were strongly protective, probably due to air conditioning use and diminished indoor allergens during hot, dry periods. Controlling for weather, total fungal spore concentrations were associated with all outcomes: per minimum to 90th percentile increase of nearly 4,000 spores/m3, asthma symptom scores increased 0.36 (95% CI, 0.16-0.56), inhaler use increased 0.33 puffs (95% CI, -0.02-0.69), and evening PEFR decreased 12.1 l/min (95% CI, -1.8-22.3). These associations were greatly enhanced by examining certain fungal types (e.g., Alternaria, basidiospores, and hyphal fragments) and stratifying on 16 asthmatics allergic to tested deuteromycete fungi. There were no significant associations to low levels of pollen or O3, but inhaler use was associated with PM10 (0.15 inhaler puffs/10 micrograms/m3; p < 0.02). These findings suggest that exposure to fungal spores can adversely effect the daily respiratory status of some asthmatics. 相似文献
97.
Yersinia enterocolitica is a rare cause of extra-intestinal disease. A case in a 60 year old butcher with hepatic cirrhosis who developed suppurative arthritis of the shoulder caused by Y enterocolitica is presented. There was no evidence of gastrointestinal infection or septicaemia. The severity of the illness was associated with various factors, including the underlying disease, the type of occupation, and the difficulties encountered in defining the optimal therapeutic regimen. 相似文献
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99.
Acute gastrointestinal haemorrhage in anticoagulated patients: diagnoses and response to endoscopic treatment. 总被引:2,自引:0,他引:2 下载免费PDF全文
The underlying diagnosis and clinical course of 52 patients who presented with severe acute gastrointestinal haemorrhage while taking the anticoagulant warfarin is reviewed. A bleeding site was identified in 83% of cases, only slightly fewer than the 92% found in a control of group of 710 patients not taking warfarin who presented in the same four year period. The degree or duration of anticoagulation was unrelated to the frequency of establishing a diagnosis. The commonest diagnosis was peptic ulcer (25 cases) and endoscopic treatment by injection or heater probe was attempted in 23 of these. The outcome in this subgroup was compared with that in 50 closely matched control subjects who had similar risk factors for rebleeding from peptic ulcer. Permanent haemostasis was achieved in (91%) of the anticoagulated and in 92% of the control patients. There were no complications related to endoscopy. Patients who present with acute gastrointestinal haemorrhage while taking warfarin usually bleed from mucosal disease. They should be endoscoped after resuscitation and those with major bleeding from a peptic ulcer should be offered endoscopic treatment. 相似文献
100.
Overexpression of parathyroid hormone-related protein in the skin of transgenic mice interferes with hair follicle development. 总被引:11,自引:3,他引:8 下载免费PDF全文
J J Wysolmerski A E Broadus J Zhou E Fuchs L M Milstone W M Philbrick 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(3):1133-1137
Parathyroid hormone-related peptide (PTHrP) was initially discovered as the cause of the syndrome of humoral hypercalcemia of malignancy. Subsequently, the PTHrP gene has been shown to be expressed in a wide variety of normal tissues, including skin. Because the biological function of PTHrP in skin remains unknown, we used the human keratin 14 promoter to target overexpression of PTHrP to the skin of transgenic mice. We achieved a 10-fold level of overexpression in skin, and human keratin 14 promoter-PTHrP transgenic mice displayed a disturbance in normal hair follicle development. These mice either failed to initiate follicle development or showed a delay in the initiation of follicles. These findings suggest that PTHrP normally plays a role in the early stages of hair follicle development and support previous speculation that the peptide may function in regulating cellular differentiation. 相似文献