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991.
992.
Philip J. Bossart M.D. F.A.C.E.P. Lenard Brunsdale M.D. Matt Hughes M.D. B. J. Manaster M.D. Ph.D. Anthony Doyle M.D. Kathy Murray M.D. David Tripp Ph.D. 《Emergency radiology》1997,4(1):26-29
To determine the utility of the lateral view of the chest in emergency department patients, records of all patients who had had 2-view chest x-rays ordered in the emergency department were reviewed retrospectively. A study radiologist recorded a reading of the posteroanterior (PA) radiograph alone. The lateral radiograph was then provided, along with the PA view, and a second reading was recorded. A comparison was then made between the first and second readings.A total of 417 sets of x-rays were included. The PA view alone successfully diagnosed or suspected 92% of pulmonary nodules, 95% of effusions, 97% of cases of emphysema, 98% of pneumonias, and 100% of cases of cardiomegaly, pulmonary edema, interstitial pulmonary disease, and atelectasis.In the emergency department patient population, lateral views of the chest have minimal diagnostic yield and therefore may be used selectively to safely decrease the amount of breast radiation exposure to young women. 相似文献
993.
Nikolaos L. Kelekis Richard C. Semelka Paul L. Molina David M. Warshauer Tonya J. Sharp Frank C. Detterbeck 《Journal of magnetic resonance imaging : JMRI》1997,7(4):652-656
To assess the reproducibility and image quality of immediate postgadolinium chelate spoiled gradient-echo MRI in demonstrating disease of the abdominal aorta. All patients (27 patients: 21 men, 6 women) with substantial disease of the abdominal aorta, who underwent abdominal MR examinations at 1.5 T between 1991 and 1995, were entered in the study. Patients were referred for evaluation of suspected aortic disease (14 patients) or other abdominal diseases (13 patients). Three experienced investigators manually measured luminal and external aortic wall diameters and rated image quality, definition of inner and outer walls, extent of disease, and presence of other abdominal abnormalities, in an independent fashion. A cardiovascular surgeon then rated all studies to determine whether clinical management could be based on the MR findings alone. There was 98 to 99% agreement in measurements of luminal and external wall diameter between the three investigators. Overall image quality was rated as good in 77.8 to 88.9% of patients. A total of 31 additional nonaortic abdominal abnormalities were detected by all observers. The cardiovascular surgeon rated 25 of 27 studies as adequate to determine clinical management based on MR findings alone. Immediate postgadolinium spoiled gradient-echo MRI is a reproducible technique for the demonstration of abdominal aortic disease and possesses good image quality. Advantages of this technique include simultaneous evaluation of other nonvascular diseases of the abdomen, short examination time, and easy implementation as part of routine abdominal MRI scanning protocol. 相似文献
994.
We predicted that children's conceptions of various self-care behaviors and social relations would be related to their degree of experience with insulin dependent diabetes mellitus (IDDM). A total of 55 children were recruited for this study in three experience groups: children with IDDM (high experience), children having a sibling with IDDM (low experience), and normal healthy children (no experience). In line with our model, children with IDDM had a more developed and sophisticated understanding of concepts associated with disease management than did either siblings of children with diabetes or the comparison group; surprisingly, experience with the disease (children with IDDM) was associated with more complex conceptions of social relations as well. 相似文献
995.
Yuji Baba Markus M. Lerch David D. Stark Akihiro Tanimoto Burkhard P. Kreft Longhai Zhao Ashok K. Saluja Mutsumasa Takahashi 《Journal of magnetic resonance imaging : JMRI》1994,4(5):647-651
Previously unreported effects of tissue storage were recently observed in the authors' experimental magnetic resonance (MR) studies. To evaluate the effect of elapsed time after excision and storage temperature on tissue relaxation time measurements, tissue samples from the liver, pancreas, kidney, testis, spleen, and brain were obtained in rats. T1 and T2 were first measured within 5 minutes of excision, and between subsequent measurements, tubes were kept in a water bath at 40°C, at room temperature (28°C), or in an ice bath (4°C). Cellular and organellar integrity was assessed with electron microscopy and correlated with the MR findings. At 40°C (20-MHz spectrometer), the T1 of liver decreased from 280 msec ± 8 to 212 msec ± 10 during the first 60 minutes; the T1 of pancreas decreased from 276 msec ± 3 to 208 msec ± 2. Other tissues showed less than a 5% decrease in T1. T2 changes were smaller than T1 changes in all tissues. Electron microscopy of pancreatic acinar cells showed postmortem changes in mitochondria evolving over the first 60 minutes after death. Manganese loading experiments implicated mitochondrial manganese stores in the observed enhanced postmortem decrease in T1. This study calls into question reported relaxation time data for liver and pancreas. MR studies of excised tissues must account for time and temperature to prevent systematic experimental errors. 相似文献
996.
K. Cartwright M. Logan C. McNulty S. Harrison R. George A. Efstratiou M. McEvoy N. Begg 《Epidemiology and infection》1995,115(3):387-397
We describe the first cluster of cases of necrotizing fasciitis (NF) in this century in the United Kingdom (UK). Between 1 January and 30 June 1994 there were six cases (five confirmed, one probable) of Streptococcus pyogenes NF in west Gloucestershire, population 320,000. Two cases died. The first two patients probably acquired their infections during the course of elective surgery performed in the same operating theatre, possibly from a nasopharyngeal carrier amongst the theatre staff. The remaining infections were community-acquired. Of 5 S. pyogenes isolates there were 2 M1 strains, 1 M3, 1 M5 and 1 M non-typeable strain. S. pyogenes NF had not been recorded in west Gloucestershire in the preceding 10 years and the incidence of S. pyogenes bacteraemia in England and Wales had not risen in the past 5 years. The two presumably theatre-acquired infections raised several issues. The need for detailed bacteriological investigation of all cases of post-surgical NF was confirmed. Clusters of S. pyogenes infection following surgery should be managed by closure of the operating theatre until all staff have been screened for carriage. Closure of an operating theatre and screening of staff following a sporadic case is probably not justified because of the infrequency of surgical cross-infection with S. pyogenes. Regular, routine screening of theatre staff is neither practical nor necessary. 相似文献
997.
Gerassimos J Mantzaris Kalliopi Petraki Michael Sfakianakis Emmanuel Archavlis Angeliki Christidou Helen Chadio-Iordanides George Triadaphyllou 《Clinical gastroenterology and hepatology》2003,1(2):122-128
BACKGROUND & AIMS: To compare the efficacy of controlled-release budesonide capsules with that of mesalamine for maintaining remission and improving quality of life (QOL) in patients with steroid-dependent Crohn's disease. METHODS: Fifty-seven patients (25 men; mean age, 32 +/- 10.1 yr) with quiescent steroid-dependent Crohn's ileitis, ileocolitis, or colitis (Crohn's disease activity index <150) entered a prospective, investigator-blind trial. Patients were eligible for treatment with azathioprine but had not consented or had developed side effects. Patients were randomized to receive budesonide 6 mg/day (n = 29) or mesalamine 1 g 3 times/day (n = 28). Follow-up assessments were made every 2 months for up to 1 year or until relapse. At each visit, quality of life (QOL) was assessed using the Inflammatory Bowel Disease Questionnaire (IBDQ). RESULTS: There were no significant differences in baseline clinical characteristics between the study groups. The 1-year relapse rate was significantly lower in the budesonide group than in the mesalamine group (55% vs. 82%; 95% confidence interval, 12.4%-41%; P = 0.045). Patients assigned to budesonide also remained in remission longer (241 +/- 114 days vs. 147 +/- 117 days; 95% confidence interval, 32.7-155.3 days; P = 0.003). Compared with mesalamine, budesonide treatment also was associated with a better QOL throughout the study (mean total IBDQ scores 165 +/- 36 vs. 182 +/- 28, respectively; 95% confidence interval, -0.4 to 34.4, P = 0.0001). This advantage was confirmed in patients' self-assessed QOL scores. CONCLUSIONS: Over a 1-year period, controlled-release budesonide was significantly more effective than mesalamine for maintaining remission and improving the QOL of patients with steroid-dependent Crohn's disease. 相似文献
998.
Daniel F. Worsley Anthony Y. Fung David B. Coupland Cori G. Rexworthy George P. Sexsmith Brian C. Lentle 《European journal of nuclear medicine and molecular imaging》1992,19(6):441-444
Unlike conventional thallium-201 myocardial imaging, technetium-99m methoxyisobutylisonitrile (MIBI) requires separate stress and rest injections. We prospectively studied 148 consecutive patients referred for myocardial perfusion studies to determine the diagnostic value of rest images once normal exercise or dipyridamole tomographic images had been obtained. In patients referred with no history of previous myocardial infarction in whom the diagnosis of coronary artery disease was suspected, 45 of 109 (41%) patients had normal stress tomographic images. Obtaining rest images did not alter the final interpretation in any of these cases. From this we infer that in patients with normal images after exercise or dipyridamole administration and no past history of myocardial infarction, 99mTc-MIBI rest images are not required. This provides several advantages including increased speed of diagnosis, decreased patient radiation exposure, improved cost efficiency and decreased demand on tomographic camera time.
Offprint requests to: A.Y. Fung 相似文献
999.
We have developed a computerized neuromuscular monitoring system (NMMS) using commercially available subsystems, i.e., computer
equipment, clinical nerve stimulator, force transducer, and strip-chart recorder. This NMMS was developed for acquisition
and analysis of data for research and teaching purposes. Computer analysis of the muscle response to stimulation allows graphic
and numeric presentation of the twitch response and calculated ratios. Since the system can store and recall data, research
data can be accessed for analysis and graphic presentation. An IBM PC/AT computer is used as the central controller and data
processor. The computer controls timing of the nerve stimulator output, initiates data acquisition, and adjusts the paper
speed of the strip chart recorder. The data processing functions include establishing control response values (when no neuromuscular
blockade is present), displaying force versus time and calculated data graphically and numerically, and storing these data
for further analysis. The general purpose nature of the computer and strip chart recording equipment allow modification of
the system primarily by changes in software. For example, new patterns of nerve stimulation, such as the posttetanic count,
can be programmed into the computer system along with appropriate data display and analysis routines. The NMMS has functioned
well in the operating room environment. We have had no episodes of electrocautery interference with the computer functions.
The automated features have enhanced the utility of the NMMS. The prime advantages of this system are (1) the ability to customize
its features by altering its controlling programs, (2) the ready availability of the hardware and software, (3) the general
purpose nature of the system, so that it is not limited to this one application, and (4) the adaptable nature of the system. 相似文献
1000.