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151.
DJ Hackam RA Superina RH Pearl 《Canadian Metallurgical Quarterly》1997,32(7):1028-31; discussion 1031-2
Current management of Hirschsprung's disease (HD) typically involves staged therapy, which necessitates multiple hospital admissions and associated costs. The authors therefore investigated the course and outcome of treating such children using a single-staged (SS) approach, and compared them with those treated via multiple-staged (MS) therapy. The cases of one hundred nine consecutive patients who presented with HD from 1991 to 1996 were reviewed. Four patients were excluded (two unrelated deaths, two with small intestinal aganglionosis). Twenty-one of the remaining 105 patients underwent SS repair. Both groups were similar in gender, age at diagnosis, and frequency of comorbidities. Repair was possible in 100% of the SS patients. Complications, including enterocolitis, occurred in 63% of patients, and did not significantly differ between groups. The outcome in SS patients was unaffected by whether the repair was performed before or after 30 days of life. The outcome was unaffected by operative weight in either group. By contrast, the number of hospital admissions and total length of stay was significantly higher in the MS group, which resulted in a twofold increase in total costs associated with MS repair compared with SS repair. These data indicate that primary repair of HD is efficacious (even in the newborn), with morbidity equal to MS repair, and requires fewer hospital admissions. The significant savings to the patient and the health care system suggest that SS repair may be an improved strategy for treating HD. 相似文献
152.
153.
YR Ortega CR Roxas RH Gilman NJ Miller L Cabrera C Taquiri CR Sterling 《Canadian Metallurgical Quarterly》1997,57(6):683-686
Cryptosporidium parvum and Cyclospora cayetanensis are protozoan pathogens that cause prolonged diarrhea in both immunocompetent and immunocompromised hosts. Cryptosporidium parvum can be transmitted via the fecal-oral route, while the exact mechanisms of transmission of Cyclospora cayetanensis have not been fully determined. Humans appear to be the sole host for the latter and a distinct seasonality has been observed in endemic areas around the world. Samples of vegetables were collected at several small markets in a periurban slum in Peru during the seasons of high and low incidence. The vegetables were washed, the supernatants were collected and centrifuged, and the pellets were resuspended in a solution of 2.5% potassium dichromate. Pellets were examined using direct microscopic observation, acid-fast staining, and immunofluorescent assays for C. parvum and Cyclospora cayetanensis oocysts. Samples were collected during three time periods: the season of low incidence, the beginning of the season of high incidence, and end of the season of high incidence. Of the total vegetables examined, 14.5% contained C. parvum oocysts and 1.8% had Cyclospora oocysts. Thus, market vegetables may provide a route by which Cryptosporidium and Cyclospora can be transmitted. Our study also suggests that washing vegetables does not completely remove Cryptosporidium and Cyclospora oocysts. 相似文献
154.
155.
RH Ruiz 《Canadian Metallurgical Quarterly》1995,41(2):114-120
The diagnostic accuracy of detailed zonography using the Scanora multimodal X-ray system was compared with that of periapical radiography. The study was based on the detection of periapical bone lesions at 259 dental sites distributed evenly throughout the dentitions of 164 patients. Each site was examined by periapical radiography and zonography, in parallel. The zonograms consisted of four detailed images that could also be read as stereopairs, in either the horizontal or vertical direction. Five observers evaluated the sites for the presence or absence of periapical osteolysis or sclerosis and apical widening of the periodontal ligament space for the whole dentition, and for three dental regions. ROC analysis revealed no significant overall or regional differences between the diagnostic accuracies of the periapical and zonographic techniques, regardless of whether the zonograms were read as sets of four images (multiview) or stereoscopic images. The sensitivity of periapical radiography was 72%, that of multiview zonography 88%, and that of stereoscopic zonography 85%. Specificities were 93%, 84% and 89%, respectively. The energy imparted during detailed zonography was 0.98 mJ. It is concluded that zonography is as good as periapical radiography for the detection of periapical pathology. 相似文献
156.
157.
Corticosteroids are effective in bringing about a clinical remission in patients with ulcerative colitis. However, in severely relapsed cases, corticosteroids are not always effective even when a high dosage is administered. In addition, the long-term use of corticosteroids often causes serious side effects. Therefore, an alternative treatment for active ulcerative colitis is necessary in order to avoid these clinical problems. In the present pilot study, the efficacy of leukocytapheresis using a centrifugal procedure was evaluated for corticosteroid-resistant, active ulcerative colitis. Fourteen patients with corticosteroid-resistant severely active ulcerative colitis were treated by leukocytapheresis. Thirteen patients (92.9%) achieved clinical remission within 4 weeks after the apheresis, and remained in remission for 8 months on average without any additional corticosteroid therapy. In the remaining patient, in whom remission was not induced, a total colectomy was performed immediately after the fourth course of leukocytapheresis. No significant side effects were noticed throughout the therapy. Both colonoscopic and histological examinations confirmed the beneficial effect of this procedure in terms of the reduction of severe inflammation of the affected colon. We found that the expression of two adhesion molecules, L-selectin and VLA4a, on the surface of peripheral leukocytes was decreased after this new therapy. 相似文献
158.
Thirteen wrist arthrodeses were performed for failed wrist implant arthroplasties between 1984 and 1992. Twelve patients were available for review, with an average follow-up period of 28 months. The original arthroplasties consisted of 8 silicone implants and 4 metal-plastic total wrist implants. The surgical method involved a tricortical iliac bone graft and an intramedullary Steinmann pin. There were 7 excellent results, 4 good results, and 1 poor result. All but 1 patient had markedly improved function with no or mild pain. Seven patients had solid fusions and 5 patients had pseudarthroses. Four pseudarthroses occurred at the graft-metacarpal junction and 1 occurred at the graft-radius junction. Each patient with a solid fusion had an excellent result. All graft-metacarpal pseudarthroses were painless and did not limit the patients' activities. There were 17 complications in 9 patients. Wrist arthrodesis can be a successful salvage procedure for failed wrist implant arthroplasty in patients with rheumatoid arthritis. However, the complication rate can be high. Owing to the high incidence of distal graft-metacarpal pseudarthrosis, we recommend using more rigid fixation techniques in patients with failed wrist arthroplasties. 相似文献
159.
A sensitive reversed-phase high-performance liquid chromatographic method with ultraviolet detection was developed for the analysis of a new angiotensin II receptor antagonist, DuP 532 (L-694,492), in human plasma and urine. The analyte and internal standard are extracted from plasma and urine at a pH between 3.3 to 3.6 by liquid-liquid extraction and analyzed on a C6 column with ultraviolet detection at 254 nm. The mobile phase is composed of acetonitrile and phosphate buffer at pH 2.5. The limits of quantification are 6 and 7.5 ng/ml for plasma and urine, respectively. 相似文献
160.
LA Farrer LA Cupples JL Haines B Hyman WA Kukull R Mayeux RH Myers MA Pericak-Vance N Risch CM van Duijn 《Canadian Metallurgical Quarterly》1997,278(16):1349-1356
OBJECTIVE: To examine more closely the association between apolipoprotein E (APOE) genotype and Alzheimer disease (AD) by age and sex in populations of various ethnic and racial denominations. DATA SOURCES: Forty research teams contributed data on APOE genotype, sex, age at disease onset, and ethnic background for 5930 patients who met criteria for probable or definite AD and 8607 controls without dementia who were recruited from clinical, community, and brain bank sources. MAIN OUTCOME MEASURES: Odds ratios (ORs) and 95% confidence intervals (CIs) for AD, adjusted for age and study and stratified by major ethnic group (Caucasian, African American, Hispanic, and Japanese) and source, were computed for APOE genotypes epsilon2/epsilon2, epsilon2/epsilon3, epsilon2/epsilon4, epsilon3/epsilon4, and epsilon4/epsilon4 relative to the epsilon3/epsilon3 group. The influence of age and sex on the OR for each genotype was assessed using logistic regression procedures. RESULTS: Among Caucasian subjects from clinic- or autopsy-based studies, the risk of AD was significantly increased for people with genotypes epsilon2/epsilon4 (OR=2.6, 95% CI=1.6-4.0), epsilon3/epsilon4 (OR=3.2, 95% CI=2.8-3.8), and epsilon4/epsilon4 (OR=14.9, 95% CI= 10.8-20.6); whereas, the ORs were decreased for people with genotypes epsilon2/epsilon2 (OR=0.6, 95% CI=0.2-2.0) and epsilon2/epsilon3 (OR=0.6, 95% CI=0.5-0.8). The APOE epsilon4-AD association was weaker among African Americans and Hispanics, but there was significant heterogeneity in ORs among studies of African Americans (P<.03). The APOE epsilon4-AD association in Japanese subjects was stronger than in Caucasian subjects (epsilon3/epsilon4: OR=5.6, 95% CI=3.9-8.0; epsilon4/epsilon4: OR=33.1, 95% CI=13.6-80.5). The epsilon2/epsilon3 genotype appears equally protective across ethnic groups. We also found that among Caucasians, APOE genotype distributions are similar in groups of patients with AD whose diagnoses were determined clinically or by autopsy. In addition, we found that the APOE epsilon4 effect is evident at all ages between 40 and 90 years but diminishes after age 70 years and that the risk of AD associated with a given genotype varies with sex. CONCLUSIONS: The APOE epsilon4 allele represents a major risk factor for AD in all ethnic groups studied, across all ages between 40 and 90 years, and in both men and women. The association between APOE epsilon4 and AD in African Americans requires clarification, and the attenuated effect of APOE epsilon4 in Hispanics should be investigated further. 相似文献