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51.
KA Cook TE Dobbs WG Hlady JG Wells TJ Barrett ND Puhr GA Lancette DW Bodager BL Toth CA Genese AK Highsmith KE Pilot L Finelli DL Swerdlow 《Canadian Metallurgical Quarterly》1998,280(17):1504-1509
CONTEXT: Acidic foods such as orange juice have been thought to be unlikely vehicles of foodborne illness. OBJECTIVE: To investigate an outbreak of Salmonella enterica serotype Hartford (Salmonella Hartford) infections among persons visiting a theme park in Orlando, Fla, in 1995. DESIGN: Review of surveillance data, matched case-control study, laboratory investigation, and environmental studies. SETTING: General community. PARTICIPANTS: The surveillance case definition was Salmonella Hartford or Salmonella serogroup C1 infection in a resident of or a visitor to Orlando in May or June 1995. In the case-control study, case patients were limited to theme park hotel visitors and controls were matched to case patients by age group and hotel check-in date. MAIN OUTCOME MEASURES: Risk factors for infection and source of implicated food. RESULTS: Sixty-two case patients from 21 states were identified. Both Salmonella Hartford and Salmonella enterica serotype Gaminara (Salmonella Gaminara) were isolated from stool samples of 1 ill person. Thirty-two case patients and 83 controls were enrolled in the case-control study. Ninety-seven percent of case patients had drunk orange juice in the theme park vs 54% of controls (matched odds ratio, undefined; 95% confidence interval, 5.2 to undefined). The orange juice was unpasteurized and locally produced. Salmonella Gaminara was isolated from 10 of 12 containers of orange juice produced during May and July, indicating ongoing contamination of juice probably because of inadequately sanitized processing equipment. CONCLUSIONS: Unpasteurized orange juice caused an outbreak of salmonellosis in a large Florida theme park. All orange juice was recalled and the processing plant closed. Pasteurization or other equally effective risk-management strategies should be used in the production of all juices. 相似文献
52.
The co-twin control design has been widely used in studying the effects of environmental factors on the development of diseases. For binary outcomes that arise from co-twin control studies, the conditional likelihood method is commonly used. This approach, however, does not readily extend to ordinal response data because the standard conditional likelihood does not exist for cumulative logit or proportional odds models. In this paper, we investigate the applicability of the random-effects and GEE approaches in analysing ordinal response data from co-twin control studies. Using both approaches, we re-analyse data from a co-twin control study of the impact of military services during the Vietnam era on post-traumatic stress disorders (PTSD). The ordinal models have considerably increased power in detecting the effects of exposure when compared to the analyses using a dichotomized response. We discuss the interpretation of the estimates from GEE and random-effect models in the context of the twin data. 相似文献
53.
SL Kugler ES Stenroos DE Mandelbaum T Lehner VV McKoy T Prossick J Sasvari K Swannick J Katz WG Johnson 《Canadian Metallurgical Quarterly》1998,79(5):354-361
Three flagellates of the family Trypanosomatidae were isolated from mango fruits (Mangifera indica) and from the stems of clover (Trifolium glomeratum) and Amaranth (Amaranthus retroflexus) in southeastern Spain and were adapted to in vitro culture in monophase media. The parasites showed an ultrastructural pattern similar to that of other species of the genus Phytomonas. Mango and clover isolates differed from amaranth isolates in ultrastructural terms. The isolates were characterized by isoenzymatic analysis and by kDNA analysis using five different restriction endonucleases. With eight of the nine enzymatic systems, mango and clover isolates were distinguished from those of amaranth. Nevertheless, with the enzymes malate dehydrogenase and superoxide dismutase, flagellates isolated from clover were differentiated from those isolated from mango. Electrophoretic and restriction-endonuclease analysis of kDNA minicircles showed similar restriction cleavage patterns for the isolates from mango and clover, whereas the patterns of the amaranth isolates differed. The results of the present study confirm that the strains isolated from mango and clover constitute a phylogenetically closely related group of plant trypanosomatids, which is more distantly related to the strain isolated from amaranth. The similarities in the results obtained for isolates from mango and clover foliage, on the one hand, and those obtained from tomato and cherimoya fruits (studied previously), on the other, as well as the geographic proximity of the different plants support the contention that only one strain is involved, albeit one strain that can parasitize different plants. Furthermore, some of the plants appear to act as reservoirs for the parasites. On the other hand, the metabolism studies using [1H]-nuclear magnetic resonance spectroscopy did not reveal that the catabolism of Phytomonas in general follows a pattern common to all the species or isolates. Phytomonas are incapable of completely degrading glucose, excreting a large part of their carbon skeleton into the medium as fermentative metabolites (acetate, ethanol, glycine, glycerol, and succinate). 相似文献
54.
DM Parenti PL Williams R Hafner MR Jacobs P Hojczyk TM Hooton TW Barber G Simpson C van der Horst J Currier WG Powderly M Limjoco JJ Ellner 《Canadian Metallurgical Quarterly》1998,12(18):2439-2446
OBJECTIVE: To determine the clinical and microbiologic benefit of adding amikacin to a four-drug oral regimen for treatment of disseminated Mycobacterium avium infection in HIV-infected patients. DESIGN: A randomized, open-labeled, comparative trial. SETTING: Outpatient clinics. PATIENTS: Seventy-four patients with HIV and symptomatic bacteremic M. avium infection. INTERVENTIONS: Rifampin 10 mg/kg daily, ciprofloxacin 500 mg twice daily, clofazimine 100 mg every day, and ethambutol 15 mg/kg orally daily for 24 weeks, with or without amikacin 10 mg/kg intravenously or intramuscularly 5 days weekly for the first 4 weeks. MAIN OUTCOME MEASURE: Clinical and microbiologic response at 4 weeks; quantitative level of bacteremia with M. avium. RESULTS: No difference in clinical response was noted with the addition of amikacin to the four-drug oral regimen, and only 25% in either group had a complete or partial response at 4 weeks. A comparable quantitative decrease in bacteremia was noted in both treatment groups, with 16% of patients being culture-negative at 4 weeks and 38% at 12 weeks. Toxicities were mainly gastrointestinal. Amikacin was well tolerated. Median survival was 30 weeks in both groups. CONCLUSIONS: The addition of amikacin to a four-drug oral regimen of rifampin, ciprofloxacin, clofazimine, and ethambutol did not provide clinical or microbiologic benefit. 相似文献
55.
E Malik W B?hm F Stoz CD Nitsch WG Rossmanith 《Canadian Metallurgical Quarterly》1998,12(11):1326-1333
BACKGROUND: Laparoscopy can be used with minimal operative morbidity to evaluate adnexal masses. We report our experience with the endoscopic approach to the diagnosis and treatment of ovarian tumors. In particular, we describe 11 patients who incidentally underwent laparoscopy and in whom the ovarian masses were found to be malignant. METHODS: Between September 1994 and September 1996, 292 patients with 316 ovarian tumors were treated laparoscopically in the Department of Obstetrics-Gynaecology, University of Ulm. We assessed vaginal ultrasonography, clinical assessment, the tumor marker CA 12-5, and the intraoperative low-power magnification for their value in predicting the final diagnosis in all laparoscopically treated ovarian tumors. RESULTS: From a total of 292 patients with ovarian tumors, 11 were diagnosed, intraoperatively or after final histologic examination, as having a malignant or borderline ovarian tumor. All applied pre- and intraoperative diagnostic procedures were by themselves too unreliable to exclude early stages of ovarian carcinoma exactly. CONCLUSIONS: On the basis of the present findings, we are tempted to conclude that laparoscopic surgery is justified in the management of ovarian tumors. Even with an accurate preoperative selection of suitable patients for laparoscopic surgery, the presence of an undetected ovarian carcinoma cannot be entirely excluded. 相似文献
56.
AG Magee BW McCrindle J Mawson LN Benson WG Williams RM Freedom 《Canadian Metallurgical Quarterly》1998,32(2):502-508
OBJECTIVES: To determine the prevalence of systemic venous collaterals after the bidirectional cavopulmonary anastomosis and the factors associated with their development. BACKGROUND: Systemic venous collaterals have been found after cavopulmonary anastomosis. Methods. Cardiac catheterization was performed in 103 patients before and after a bidirectional cavopulmonary anastomosis. RESULTS: After surgery, 51 venous collaterals were identified in 32 patients (31%). Collateral development was associated with an abnormal superior vena caval connection (56% incidence vs. 26% with a single right superior vena cava, p = 0.01) and postoperative factors including pulmonary artery distortion (53% incidence vs. 22% without distortion, p = 0.002); increased superior vena caval mean pressure (14 +/- 5 mm Hg versus 11 +/- 4 mm Hg with no collaterals, p = 0.0002); increased pulmonary artery mean pressure (13 +/- 4 mm Hg vs. 11 +/- 4 mm Hg with no collaterals, p = 0.02); lower right atrial mean pressure (5 +/- 2 mm Hg vs. 6 +/- 3 mm Hg with no collaterals, p = 0.04); and increased mean gradient between superior vena cava and right atrium (8 +/- 3 mm Hg vs. 5 +/- 4 mm Hg with no collaterals, p = 0.0002). Using multiple logistic regression, only this last factor was independently associated with collateral development with an odds ratio per 1 mm Hg of 1.33 (95% CI 1.12-1.58, p = 0.001) for their presence. CONCLUSIONS: Systemic venous collaterals occur frequently after a bidirectional cavopulmonary anastomosis and are found postoperatively when a significant pressure gradient occurs between cava and right atrium. 相似文献
57.
HK Najm GS Van Arsdell S Watzka L Hornberger JG Coles WG Williams 《Canadian Metallurgical Quarterly》1998,116(6):905-913
OBJECTIVE:The objective was to explore the best management algorithm for atrioventricular septal defect in conjunction with tetralogy of Fallot. METHODS: We reviewed the cases of 38 children referred to our division (March 1981-August 1997) who had atrioventricular septal defect associated with tetralogy of Fallot; 32 (84%) had Down syndrome. Twenty-one received initial palliation with a systemic-to-pulmonary artery shunt; of these, 2 (9.5%) died before complete repair. Thirty-one children underwent complete repair; 14 of these (45%) had undergone initial palliation (mean age at shunt 20 +/- 24 months). Right ventricular outflow obstruction was relieved by a transannular patch in 22 (71%); 14 (64% of 22) had a monocuspid valve inserted. Four required an infundibular patch. RESULTS: Two children (6.4%) died early after repair; 1 had undergone previous palliation. Patients with palliation underwent repair at an older age (78 vs 36 months), required longer ventilatory support (8 vs 4 days) and inotropic support (8 vs 4 days), and had longer intensive care stays (11 vs 6 days) and hospital stays (24 vs 15 days). Eleven children (35%) underwent reoperation, 7 (58%) for right ventricular outflow reconstruction and pulmonary arterioplasty. Reoperation was more frequent in the palliation group than in the primary operation group (64% vs 12%). The single late death was related to a reoperation in the palliation group. CONCLUSIONS: Atrioventricular septal defect with tetralogy of Fallot can be repaired with a low mortality rate. Initial palliation with a shunt resulted in a more complex postoperative course and a higher reoperative rate. Primary repair is superior to initial palliation with later repair. 相似文献
58.
WG Junger DB Hoyt RE Davis C Herdon-Remelius S Namiki H Junger W Loomis A Altman 《Canadian Metallurgical Quarterly》1998,101(12):2768-2779
Excessive neutrophil activation causes posttraumatic complications, which may be reduced with hypertonic saline (HS) resuscitation. We tested if this is because of modulated neutrophil function by HS. Clinically relevant hypertonicity (10-25 mM) suppressed degranulation and superoxide formation in response to fMLP and blocked the activation of the mitogen activated protein kinases (MAPK) ERK1/2 and p38, but did not affect Ca2+ mobilization. HS did not suppress oxidative burst in response to phorbol myristate acetate (PMA). This indicates that HS suppresses neutrophil function by intercepting signal pathways upstream of or apart from PKC. HS activated p38 by itself and enhanced degranulation in response to PKC activation. This enhancement was reduced by inhibition of p38 with SB203580, suggesting that p38 up-regulation participates in HS-induced enhancements of degranulation. HS had similar effects on the degranulation of cells that were previously stimulated with fMLP, but had no effect on its own, suggesting that HS enhancement of degranulation requires another signal. We conclude that depending on other stimuli, HS can suppress neutrophil activation by intercepting multiple receptor signals or augment degranulation by enhancing p38 signaling. In patients HS resuscitation may reduce posttraumatic complications by preventing neutrophil activation via chemotactic factors released during reperfusion. 相似文献
59.
RJ Whitley MA Jacobson DN Friedberg GN Holland DA Jabs DT Dieterich WD Hardy MA Polis TA Deutsch J Feinberg SA Spector S Walmsley WL Drew WG Powderly PD Griffiths CA Benson HA Kessler 《Canadian Metallurgical Quarterly》1998,158(9):957-969
OBJECTIVE: To provide recommendations for the treatment of acquired immunodeficiency syndrome-related cytomegalovirus (CMV) end-organ diseases, including retinitis, colitis, pneumonitis, and neurologic diseases. PARTICIPANTS: A 17-member panel of physicians with expertise in clinical and virological research and inpatient care in the field of CMV diseases. EVIDENCE: Available clinical and virological study results. Recommendations are rated according to the quality and strength of available evidence. Recommendations were limited to the treatment of CMV diseases; prophylaxis recommendations are not included. PROCESS: The panel was convened in February 1997 and met regularly through November 1997. Subgroups of the panel summarized and presented available information on specific topics to the full panel; recommendations and ratings were determined by group consensus. CONCLUSIONS: Although the epidemiological features of CMV diseases are changing in the setting of potent, combination antiretroviral therapy, continued attention must be paid to CMV diseases in patients infected with the human immunodeficiency virus to prevent irreversible endorgan dysfunction. The initial and maintenance treatment of CMV retinitis must be individualized based on the characteristics of the lesions, including location and extent, specific patient factors, and characteristics of available therapies among others. Management of relapse or refractory retinitis must be likewise individualized. Ophthalmologic screening for patients at high risk for retinitis or who have a prior diagnosis of extraretinal disease is recommended. Recommendations for gastrointestinal, pulmonary, and neurologic manifestations are included. 相似文献
60.
S Achenbach W Moshage D Ropers J Nossen WG Daniel 《Canadian Metallurgical Quarterly》1998,339(27):1964-1971
BACKGROUND: Reliable noninvasive assessment of coronary-artery stenoses and occlusions would constitute an advantage in the care of patients with known or suspected coronary artery disease. We investigated the accuracy of contrast-enhanced electron-beam computed tomography (CT) for the detection of high-grade coronary-artery stenoses and occlusions. METHODS: Electron-beam CT was performed in 125 patients. After intravenous injection of a contrast agent, 40 cross-sectional images of the heart were acquired during inspiration, triggered by the electrocardiogram in diastole. Three-dimensional reconstructions of the heart and coronary arteries were rendered to facilitate evaluation of the images. The proximal and middle segments of the major coronary arteries were evaluated for the presence or absence of high-grade stenoses and occlusions. The results were compared with those of invasive coronary angiography in a blinded fashion. RESULTS: Because of technical problems that impaired the quality of the images, 124 (25 percent) of the 500 coronary arteries studied (left main, left anterior descending, left circumflex, and right coronary) in a total of 125 patients were excluded from evaluation. No vessels could be evaluated in 19 patients (15 percent), and another 28 patients (22 percent) had one, two, or three vessels that could not be evaluated. In the remaining coronary arteries with adequate image quality, electron-beam CT permitted visualization of 69 of 75 high-grade stenoses and occlusions (sensitivity, 92 percent), whereas in 282 of 301 arteries, the absence of high-grade stenoses and occlusions was correctly detected (specificity, 94 percent). CONCLUSIONS: When image quality is adequate, electron-beam CT may be useful to detect or rule out high-grade coronary-artery stenoses and occlusions. 相似文献