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Late-onset and Recurrent Neonatal Group B Streptococcal Disease Associated with Breast-milk Transmission 总被引:2,自引:0,他引:2
Michael Kotiw Gwang W. Zhang Grant Daggard Elizabeth Reiss-Levy John W. Tapsall Andrew Numa 《Pediatric and developmental pathology》2003,6(3):251-256
The purpose of the study was to determine the epidemiological relationships in three unrelated cases of neonatal late-onset Group B streptococcal (GBS) disease and maternal breast-milk infection with GBS. All deliveries were by cesarean section; case 1 was at term, and cases 2 and 3 were at 32- and 33-wk gestation, respectively. Case 1 relates to a mother with clinical mastitis and recurrent GBS infection in a 20-day-old male infant. Following antibiotic therapy and cessation of breast-feeding, the infant recovered without sequelae. Case 2 refers to a mother with clinical mastitis and the occurrence of late-onset GBS disease in 5-wk-old male twins. Despite intervention, one infant died and the second became ill. Following antibiotic therapy and cessation of breast-feeding, the surviving infant recovered without sequelae. Case 3 refers to a mother with sub-clinical mastitis and late-onset GBS infection occurring in a 6-day-old female twin. Following intervention, the infant recovered but suffered a bilateral thalamic infarction resulting in developmental delay and a severe seizure disorder. Following recovery of GBS from an inapparent mastitis and cessation of breast-feeding, the second infant remained well. Blood cultures from all affected infants and maternal breast milk were positive for GBS. Epidemiological relationships between neonatal- and maternal-derived GBS isolates were confirmed by a random amplified polymorphic DNA polymerase chain reaction assay (RAPD-PCR). This study is significant in that it has demonstrated that maternal milk (in cases of either clinical or sub-clinical mastitis) can be a potential source of infection resulting in either late-onset or recurrent neonatal GBS disease. 相似文献
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Short-Ti inversion-recovery pulse sequence: analysis and initial experience in cancer imaging 总被引:2,自引:0,他引:2
Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy. 相似文献
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Sixteen cases of histopathologically proved solitary rectal ulcer syndrome were encountered. Fifteen patients underwent barium enema study; in nine cases the findings--including rectal stricture, granularity of the mucosa, and thickened rectal folds-were nonspecific. In six cases the study was normal. All patients had a long history of defecation disorders, and defecography was performed in all. In seven cases, intussusception of the rectal wall was seen; in another case the intussusception was accompanied by a rectocele. One case showed rectal prolapse. In four cases, failed relaxation of the puborectalis occurred and prevented the passage of the bolus; in another case there was abnormal perineal descent. In two patients studies were normal. In patients with defecation disorders, the possibility of this syndrome should be considered. Defecography is the method of choice for establishing the diagnosis. 相似文献
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