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41.
Lasser  EC; Lang  JH; Lyon  SG; Hamblin  AE; Howard  MM 《Radiology》1981,140(1):11-15
An in vitro is described that attempts to detect patients with a potential for adverse systemic reactions to contrast material. This test involves measuring the rate of conversion of prekallikrein to kallikrein under certain standard conditions. In a preliminary retrospective study, the test could be used to identify such patients with a sensitivity of 88%, a specificity of 82%, and a predictive value of 79%.  相似文献   
42.
Patient dosage in computed tomography   总被引:1,自引:0,他引:1  
McCullough  EC; Payne  JT 《Radiology》1978,129(2):457
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43.
A 68-year old man with fever chills and a diastolic murmur was diagnosed with aortic-valve endocarditis caused by coagulase-negative Staphylococcus lugdunensis. The clinical condition initially improved with antibiotic therapy. On day seven, transoesophageal echocardiography revealed large abscesses extending from the aortic root to the left ventricular wall. Emergency cardiac surgery was performed successfully and a stentless bioprosthetic valve was inserted. S. lugdunensis endocarditis is known for its aggressive clinical course with valve destruction, abscess formation and embolic complications despite appropriate antibiotics. Antibiotic treatment alone is associated with a high mortality rate which can be reduced by early valve replacement.  相似文献   
44.
This article evaluates past work on heroin and crack cocaine epidemics by comparing it with the increase in Ecstasy use in the late 1990s. First of all, the authors make the case that there was, in fact, a dramatic increase in Ecstasy use in the late 1990s. Following that is a review of the rise and fall of several different Ecstasy scenes beginning in the 1960s. The most recent rise, in the late 1990s, requires a broadening of the theory of epidemics to include longer historical waves of change, so we do that by reviewing work on post World War II trends in social disconnection and consumerism. We then shift to a marketing rather than a public health framework and look at the nature of the Ecstasy "product," both its good and bad characteristics. Finally, we describe the narrative mechanism, developed in our earlier work, that plausibly explains why use rose when it did, given the needs of the market. The article concludes by discussing the changes this case motivates for our theory, particularly in light of globalized and normalized drug use that at the moment appears to be the current context for illicit drug use.  相似文献   
45.
46.
AIM: To assess the role of etamsylate in reducing the risk of haemorrhagic brain damage and its consequences. DESIGN: Follow up of babies recruited into a randomised controlled trial. METHODS: A total of 334 infants born before 33 weeks gestation in France and Greece were randomly allocated within the first four hours of birth either to receive etamsylate or to act as controls. The principal outcomes in the trial were death or impairment and/or disability at the age of 2 years. RESULTS: Fifty nine children were lost to follow up. A total of 115 (34%) either died or had some impairment or disability, and 88 (26%) either died or had severe impairment or disability at 2 years of age. These outcomes did not differ significantly between the two randomised groups: relative risks and 95% confidence intervals 1.14 (0.78 to 1.4) and 1.17 (0.82 to 1.68) respectively. The findings were similar for all the prespecified subgroup analyses stratified by key prognostic factors at trial entry: country of birth, gestational age < or >or= 29 weeks, inborn or outborn, age < or >or= 1 hour, and with or without cerebral scan abnormality. CONCLUSION: These findings do not support the use of etamsylate. Other strategies need to be evaluated for the prevention of mortality and morbidity in these vulnerable infants.  相似文献   
47.
Oral oseltamivir treatment of influenza in children   总被引:28,自引:0,他引:28  
BACKGROUND: Oral oseltamivir administration is effective treatment for influenza in adults. This study was conducted to determine the efficacy, safety and tolerability of oseltamivir in children with influenza. METHODS: In this randomized, double blind, placebo-controlled study, children 1 through 12 years with fever [> or =100 degrees F (> or =38 degrees C)] and a history of cough or coryza <48 h duration received oseltamivir 2 mg/kg/dose or placebo twice daily for 5 days. The primary efficacy endpoint was the time to resolution of illness including mild/absent cough and coryza mild/absent, return to normal activity and euthermia. RESULTS: Of 695 enrolled children 452 (65%) had influenza (placebo, n = 235; oseltamivir, n = 217). Among infected children the median duration of illness was reduced by 36 h (26%) in oseltamivir compared with placebo recipients (101 h; 95% confidence interval, 89 to 118 vs. 137 h; 95% confidence interval, 125 to 150; P < 0.0001). Oseltamivir treatment also reduced cough, coryza and duration of fever. New diagnoses of otitis media were reduced by 44% (12% vs. 21%). The incidence of physician-prescribed antibiotics was significantly lower in influenza-infected oseltamivir (68 of 217, 31%) than placebo (97 of 235, 41%; P = 0.03) recipients. Oseltamivir therapy was generally well-tolerated, although associated with an excess frequency of emesis (5.8%). Discontinuation because of adverse events was low in both groups (1.8% with oseltamivir vs. 1.1% with placebo). Oseltamivir treatment did not affect the influenza-specific antibody response. CONCLUSIONS: Oral oseltamivir administration is an efficacious and well-tolerated therapy for influenza in children when given within 48 h of onset of illness.  相似文献   
48.
BACKGROUND: The objective of this study is to assess whether hepatitis A vaccine is immunogenic and well tolerated when administered to 12-month-old children alone or concomitantly with other routinely administered pediatric vaccines. METHODS: Six hundred seventeen healthy 12-month-old children were randomized to receive dose 1 of hepatitis A vaccine given alone or concomitantly with measles-mumps-rubella vaccine and varicella vaccine and dose 2 of hepatitis A vaccine given alone or concomitantly with diphtheria-tetanus-acellular pertussis vaccine and optionally with oral or inactivated poliovirus vaccine. Participants were followed for clinical adverse experiences and serologic responses to all vaccine antigens. Antibody responses were compared with historical controls for some indices. RESULTS: The safety profile was generally comparable whether hepatitis A vaccine was administered alone or concomitantly with other vaccines. When administered alone, the hepatitis A seropositivity rate was 98.3% and 100% for dose 1 and dose 2, respectively, and after dose 2 was similar to historical rates and the geometric mean titers were similar between initially seropositive and initially seronegative subjects (6207 and 6810 mIU/mL, respectively). After concomitant administration with hepatitis A vaccine, antibody responses to measles, mumps, rubella, diphtheria, tetanus and filamentous hemagglutinin (98.8%, 99.6%, 100%, 98.6%, 100% and 83.3%, respectively) were similar to historical controls and response to poliovirus was demonstrated, but immune responses to varicella zoster virus (79%) and pertussis toxoid (76%) were inferior to historical controls. CONCLUSIONS: Hepatitis A vaccine is highly immunogenic and generally well tolerated when administered to healthy children as young as 12 months of age regardless of initial hepatitis A serostatus and can be administered concomitantly with measles-mumps-rubella vaccine and oral or inactivated poliovirus vaccine.  相似文献   
49.
Thyroid dysfunction can develop in patients with Hodgkin's disease who are treated with mantle irradiation. During the period 1970-89, the records of 320 patients who received mantle irradiation and who had thyroid function tests (TFT) were retrospectively reviewed. The median age was 30 years (range, 7-69 years). The median mantle and thyroid dose was 36 Gy (range, 30-40 Gy) and 39.8 Gy (range, 32-65 Gy), respectively. Overall thyroid dysfunction was present in 39% of the patients. Clinical hypothyroidism was seen in 10% and biochemical hypothyroidism was noted in 25%. Hyperthyroidism was found in 4% of patients. Thyroid nodules had developed in six patients (2%), of which those in four patients were malignant. Age, sex, histological subtype, stage of disease, dose, lymphangiogram and treatment with chemotherapy were not significant factors in the development of thyroid dysfunction. The narrow dose range prevented adequate analysis of dose effect. The results indicate that the incidence of thyroid abnormalities is high enough to warrant regular TFT assessment with pre-irradiation levels and follow-up testing for life because the development of abnormalities can occur many years later. Thyroid examination should form part of the routine follow-up examination and any abnormality should be promptly investigated.  相似文献   
50.
Dershaw  DD; Shank  B; Reisinger  S 《Radiology》1987,164(2):455-461
Following local excision and definitive irradiation of 163 breast cancers in 160 women, alterations in mammographic patterns were observed for up to 7 years. Skin thickening was observed in 96% of mammograms obtained within 1 year of completing therapy and was most pronounced in women treated with iridium implant, chemotherapy, or axillary dissection. In 76% of mammograms, alterations in the parenchymal pattern, including coarsening of stroma and increased breast density, were seen at 1 year. Neither skin nor parenchymal changes progressed after 1 year. Within 3 years of treatment the parenchymal density, which usually regressed, did not change in all patients. At 3 years skin thickness and the parenchymal pattern had returned to normal in less than 50% of the breasts of these women. Scars developed in approximately one-quarter of women. They were present on the initial post-treatment mammogram and remained unchanged on serial studies. Coarse, benign calcifications also developed in the breasts of about one-quarter of women. Microcalcifications developed in 11 breasts; biopsy specimens of six were benign. Benign microcalcifications may be related to therapy.  相似文献   
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