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31.
Anti-2,4-dinitrophenyl reaginic antibody has been induced in the atopic dog and compared with anti-ragweed reaginic antibody of spontaneous canine atopic hypersensitivity. Immunization of an atopic dog with ragweed hypersensitivity with dinitrophenylated ragweed pollen produced a high and sustained level of canine reaginic anti-DNP antibody. The induced and spontaneous forms of canine reaginic antibodies were shown to be identical in heat lability, sulfhydryl sensitivity, molecular size, charge, in their ability to remain fixed at passively-sensitized dermal sites for a prolonged period, and in their capacity to sensitized homologous white blood cells from normal donors for an immunospecific release of histamine. The induced anti-DNP and spontaneous anti-ragweed reaginic antibodies were physically separated and immunochemically differentiated from six other classes of canine immunoglobulins: γ2a, γ2b, γ2c, γ1, γA and γM, and shown to be members of a distinct class of canine immunoglobulins analogous to human γE (IgE).A high incidence of spontaneous atopic hypersensitivity has been observed in the progeny of the atopic dog.  相似文献   
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Rotavirus A (RVA) is the leading cause of acute viral gastroenteritis in children under 5 years of age worldwide. G9P[8] is a common RVA genotype that has been persistently prevalent in Jiangsu, China. To determine the genetic diversity of G9P[8] RVAs, 7 representative G9P[8] strains collected from Suzhou Children’s Hospital between 2010 and 2016 (named JS2010‐JS2016) were analyzed through whole‐genome sequencing. All evaluated strains showed the Wa‐like constellation G9‐P[8]‐I1‐R1‐C1‐M1‐A1‐N1‐T1‐E1‐H1. Furthermore, phylogenetic analysis revealed that the VP7 genes of all strains clustered into lineage G9‐III and G9‐VI. With the exception of strain JS2012 (P[8]‐4), the VP4 sequences of all strains belonged to the P[8]‐3 lineage. Sequencing further revealed that amino acid substitutions were present in the antigenic regions of the VP7 and VP4 genes of all strains. Moreover, there were multiple substitutions in antigenic sites I and II of the nonstructural protein 4 (NSP4) genes, whereas the other NSP genes were relatively conserved. In conclusion, our phylogenetic analysis of these 7 G9P[8] strains suggests that RVA varied across regions and time. Therefore, our findings suggest that continued surveillance is necessary to explore the molecular evolutionary characteristics of RVA for better prevention and treatment of acute viral gastroenteritis.  相似文献   
35.
The ageing ovary appears to be characterized by depletion of primordial follicles. The relationship between infertility and the number of follicles in the ovarian cortex is not known. Moreover, there are no accurate markers or clinical methods to predict the decline in ovarian reserve. This study investigates the correlation between early follicular follicle stimulating hormone, ovarian size and follicular density in 60 infertile women aged 19-45 years (mean = 34.4 +/- 5.5). An ovarian biopsy was taken from each patient while performing diagnostic laparoscopy (n = 28) or laparotomy for tubal surgery or myomectomy (n = 32). The median number of follicles was similar in tubal and unexplained infertility patients (9.5 versus 5.5). Increasing age showed a significant negative correlation with follicular density and ovarian volume (r = -0.46, P = 0.0003;. r = -0.43, P = 0.0016, respectively). In women > or = 35 years of age the ovarian volume showed a strong correlation with follicular density (r = 0.71, P < 0.0001). Our results indicate that infertile women in their late thirties and over have a decreased ovarian reserve which could possibly be predicted by ovarian volume measurement. Ovarian biopsy may have a place as part of infertility evaluation in older women.   相似文献   
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OBJECTIVE: The purpose of this study was to determine whether the rate of polyp detection and the quality of air-contrast barium enema (ACBE) procedures performed by technologists differ from those performed by radiologists. CONCLUSION: Our results showed that well-trained certified technologists can perform ACBE similar in overall quality and accuracy to ACBE performed by attending physicians and residents. Training technologists to perform ACBE may help to alleviate the radiology staffing shortage in the United States.  相似文献   
37.
Coronary artery bypass grafts: visualization with MR imaging   总被引:1,自引:0,他引:1  
Gomes  AS; Lois  JF; Drinkwater  DC  Jr; Corday  SR 《Radiology》1987,162(1):175
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38.
Wilson  AJ; Totty  WG; Murphy  WA; Hardy  DC 《Radiology》1989,173(2):329-333
One hundred two computed tomographic (CT) arthrograms of the shoulder were retrospectively reviewed and compared with conventional double-contrast arthrograms from 101 patients (24 females and 77 males aged 9-70 years). One- to 4-year follow-up was obtained in 84 patients, 40 of whom underwent open-shoulder surgery or arthroscopy. Morphology of the normal portions of each labrum was categorized according to length, width, and tip shape. Correlation between morphology and age was weak, but abnormal labra were more common in younger patients. Conventional radiography was more accurate for detecting bony glenoid margin fractures, but CT was more accurate for detecting Hill-Sach fractures. CT was also more reliable than conventional arthrography in the detection of rotator cuff tears. Hence, few if any conventional radiographs are necessary between contrast material injection and CT imaging. A reduction in the number of images obtained will result in decreased radiation dose, less cost, and shorter examination time without loss of diagnostic accuracy.  相似文献   
39.
The authors studied the impact of edge enhancement and gray scale polarity reversal on the detection of subtle lung cancers. Three experienced readers reviewed 46 biopsy-proved subtle lung cancers and 46 normal controls on chest radiographs that had been digitized into a 1,024 X 1,536-pixel matrix 8 bits deep. Receiver-operating characteristics (ROC) analysis of 1,656 pooled observations indicated that performance was best with the unmodified images (ROC area = 0.83), degraded by moderate enhancement of medium frequencies (ROC area = 0.80), and markedly impaired by severe enhancement of low frequencies (ROC area = 0.69). Gray scale polarity reversal further degraded performance (unenhanced ROC area = 0.74; moderately enhanced ROC area = 0.76; severely enhanced ROC area = 0.76). The authors conclude that edge enhancement and gray scale polarity reversal can impair the detectability of subtle lung cancers on digitized radiographs of medium resolution.  相似文献   
40.
A baby with unilateral cleft lip, midline cleft palate and hypertelorism developed meningitis in the first 48 h of life. Examination of the nasopharynx showed a soft tissue mass, which was confirmed as a basal encephalocele by computed tomography. There was also congenital hydrocephalus and the corpus callosum was absent. Surgical treatment included repair of the anterior basal skull defect, repair of the lip and palate, and ventriculo-peritoneal shunt. There is currently evidence of developmental delay and right-sided visual impairment due to Morning Glory syndrome. This case demonstrates that basal encephalocele should be considered in any baby with midline facial deformity who develops meningitis.  相似文献   
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