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51.
The efficacy of thickened feedings for the treatment of gastroesophageal reflux in infancy was evaluated. Fifty-two infants were examined with prolonged pH monitoring of the distal esophagus after feedings of apple juice or apple juice thickened with rice cereal. All infants had a minimum of three feedings of both thickened and unthickened juice. The recordings of distal esophageal pH were analyzed for the percent of time the pH was less than 4 in the first 2 hours after each feeding. The infants were maintained in the following positions after feeding: prone (n = 29), prone-board with the head elevated 30 degrees from horizontal (n = 29), supine (n = 7), and unrestricted (n = 21). We found no significant difference in the percent of time with reflux with thickened versus unthickened feedings except in those infants maintained in the 30-degree prone position. In the first 2 hours after eating thickened juice, infants maintained in this position had increased esophageal reflux time (P less than 0.006). Further analysis revealed that 33% of the infants had a greater than 30% increase in esophageal reflux time after thickened feedings. Our study suggests that the immediate effect of thickened feedings on gastroesophageal reflux in infants is unpredictable. 相似文献
52.
Congenital pancreatic hypoplasia: a syndrome of exocrine and endocrine pancreatic insufficiency 总被引:3,自引:0,他引:3
W E Winter N K Maclaren W J Riley P P Toskes J Andres A L Rosenbloom 《The Journal of pediatrics》1986,109(3):465-468
We describe two brothers with small size at birth, early-onset insulin-dependent diabetes, and pancreatic exocrine insufficiency. In contrast to the findings in pancreatic aplasia, their serum C-peptide and glucagon levels were measurable. These findings, in concert with their clinical courses, are consistent with the diagnosis of congenital pancreatic hypoplasia. 相似文献
53.
Antibodies against follicle-stimulating hormone (anti-FSH) are present in infertile female sera. Follicle-stimulating hormone as antigen is present in female sera and introduced to the genital tract mucosa as a constituent of semen. The female immune system is activated by semen constituents during insemination to induce mucosal tolerance. We found that circulating anti-FSH IgA correlated with IgA against sperm surface antigens in female patients undergoing IVF. Our results suggest that anti-FSH and anti-sperm IgA could share antigenic origin, being induced possibly by mucosal tolerance to semen. 相似文献
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Babusai Rapaka Daniel B. Maselli Gontrand Lopez-Nava Inmaculada Bautista-Castao Reem Matar Veeravich Jaruvongvanich Eric J. Vargas Andrew C. Storm Andres Acosta Barham K. Abu Dayyeh 《中华医学杂志(英文版)》2022,135(10):1234
Background:Endoscopic bariatric therapies can help address widening management gaps in obesity. Their ability to facilitate weight loss is largely tied to influences on appetite through perturbations of gastric emptying and accommodation. As these tools gain traction in obesity therapy, their physiologic underpinnings require exploration, which may enhance efficacy, tolerance, and patient-tailored care.Methods:We prospectively assessed consecutive subjects with fluid-filled intragastric balloons (IGBs) (n = 18) placed between October 2016 and June 2017 or underwent endoscopic sleeve gastroplasty (ESG) (n = 23) from March 2018 to June 2018. Patients underwent physiologic appraisal at 3 months with 13C-spirulina-based gastric emptying breath test to determine time to half emptying (T50), as well as maximum tolerated volume (MTV) of a standard nutrient drink test. Changes in T50 and MTV at 3 months were compared with percent total body weight loss (%TBWL) at 3 and 6 months using best-fit linear regression.Results:The change in T50 at 3 months correlated with %TBWL at 3 months for IGB (P = 0.01) and ESG (P = 0.01) but with greater impact on %TBWL in IGB compared to ESG (R2 = 0.42 vs. 0.26). Change in T50 at 3 months was predictive of weight loss at 6 months for IGB (P = 0.01) but not ESG (P = 0.11). ESG was associated with greater decrease in MTV compared to IGB (340.25 ± 297.97 mL vs. 183.00 ± 217.13 mL, P = 0.08), indicting an enhanced effect on satiation through decreased gastric accommodation. Changes in MTV at 3 months did not correlate with %TBWL for either IGB (P = 0.26) or ESG (P = 0.49) but trended toward significance for predicting %TBWL at 6 months for ESG (P = 0.06) but not IGB (P = 0.19).Conclusion:IGB and ESG both induce weight loss but likely through distinct gastric motor function phenotypes, and gastric emptying may predict future weight loss in patients with IGB. 相似文献
56.
Edelman RR Salanitri G Brand R Dunkle E Ragin A Li W Mehta U Berlin J Newmark G Gore R Patel B Carillo A Vu A 《Investigative radiology》2006,41(2):175-180
OBJECTIVES: We sought to perform a preliminary comparison of signal-to-noise ratio (SNR) and image quality for magnetic resonance imaging (MRI) of the pancreas at 1.5 and 3 T. MATERIALS AND METHODS: Two imaging cohorts were studied using a T2-weighted, single-shot fast spin-echo pulse sequence and a T1-weighted, fat-suppressed 3D gradient-echo pulse sequence. In the first cohort, 4 subjects were imaged using identical imaging parameters before and after contrast administration at 1.5 and 3.0 T. The SNR was quantified for the pancreas as well as for the liver, spleen, and muscle. In a second cohort of 12 subjects in whom the receiver bandwidth was adjusted for field strength, SNR measurements and qualitative rankings of image quality were performed. RESULTS: In the study cohort using identical imaging parameters at both magnetic field strengths, the mean (SD) ratios of SNR at 3.0 to 1.5 T of the single-shot fast spin-echo images for the pancreas, liver, spleen, and muscle were 1.63 (0.39), 1.82 (0.39), 1.45 (0.18), 2.01 (0.16), respectively. For the precontrast fat-suppressed 3D gradient-echo sequence, the corresponding ratios were 1.28 (0.29), 1.26 (0.30), 1.16 (0.27), and 1.76 (0.45), respectively; for the arterial phase, the corresponding ratios were 2.02 (0.28), 1.60 (0.42), 1.47 (0.26), and 1.94 (0.32), respectively; and for the delayed postcontrast phase, the corresponding ratios were 1.63 (0.51), 2.01 (0.25), 1.66 (0.06), and 2.31 (0.47), respectively. The SNR benefit of 3.0 T was significantly greater on contrast-enhanced as compared with noncontrast T1-weighted 3D gradient-echo images. In the second study cohort, SNR was superior at 3.0 T, although the use of a reduced readout bandwidth at 1.5 T substantially diminished the advantage of the higher field system. With qualitative comparison of images obtained at the 2 magnetic field strengths, the fat-suppressed 3D gradient-echo images obtained at 3.0 T were preferred, whereas the single shot fast spin-echo images obtained at 1.5 T were preferred because of better signal homogeneity. CONCLUSIONS: Our results in a small cohort of volunteers and patients demonstrate a marked improvement in SNR at 3.0 T compared with 1.5 T (by a factor of 2 in some cases) when identical imaging parameters were used. The SNR advantage at 3.0 T is diminished but persists when the receiver bandwidth is adjusted for magnetic field strength. The results suggest that 3.0 T may offer promise for improved body MRI, although further technical development to optimize SNR and improve signal homogeneity will be needed before its full potential can be achieved. 相似文献
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Cervantes Bustamante R Ocampo del Prado LC Zárate Mondragón F Mata Rivera N Ramírez-Mayans JA Mora Tiscareño MA García Campos LN 《Revista de gastroenterologia de Mexico》2003,68(4):266-270
Peutz-Jeghers syndrome is an autonomic dominant disease characterized by hamartomatous polyps and mucocutaneous hyperpigmentation. We present 16 cases; females were more affected. The most common presenting complaints were of gastrointestinal tract. All polyps found were hamartomatous with general distribution through gastrointestinal tract. Endoscopic polypectomy should be carried out for treatment. Radiologic, endoscopic and histologic studies should be conducted for long-term follow-up, because of high risk of malignancy. 相似文献
59.
Cervantes RB Stringer JR Shao C Tischfield JA Stambrook PJ 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(6):3586-3590
Pluripotent embryonic stem (ES) cells have been used to produce genetically modified mice as experimental models of human genetic diseases. Increasingly, human ES cells are being considered for their potential in the treatment of injury and disease. Here we have shown that mutation in murine ES cells, heterozygous at the selectable Aprt locus, differs from that in embryonic somatic cells. The mutation frequency in ES cells is significantly lower than that in mouse embryonic fibroblasts, which is similar to that in adult cells in vivo. The distribution of spontaneous mutagenic events is remarkably different between the two cell types. Although loss of the functional allele is the predominant mutation type in both cases, representing about 80% of all events, mitotic recombination accounted for all loss of heterozygosity events detected in somatic cells. In contrast, mitotic recombination in ES cells appeared to be suppressed and chromosome loss/reduplication, leading to uniparental disomy (UPD), represented more than half of the loss of heterozygosity events. Extended culture of ES cells led to accumulation of cells with adenine phosphoribosyltransferase deficiency and UPD. Because UPD leads to reduction to homozygosity at multiple recessive disease loci, including tumor suppressor loci, in the affected chromosome, the increased risk of tumor formation after stem cell therapy should be viewed with concern. 相似文献
60.