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71.
72.
Fetal lung volume: estimation at MR imaging-initial results 总被引:6,自引:0,他引:6
Rypens F Metens T Rocourt N Sonigo P Brunelle F Quere MP Guibaud L Maugey-Laulom B Durand C Avni FE Eurin D 《Radiology》2001,219(1):236-241
PURPOSE: To plot normal fetal lung volume (FLV) obtained with fast spin-echo magnetic resonance (MR) images against gestational age; to investigate the correlation between lung growth and fetal presentation, sex, and ultrasonographic (US) biometric measurements; and to investigate its potential application in fetuses with thoracoabdominal malformations. MATERIALS AND METHODS: In a prospective multicenter study, 336 fetuses suspected of having central nervous system disorders underwent fast spin-echo T2-weighted lung MR imaging. Data obtained at 21-38 weeks gestation in 215 fetuses without thoracoabdominal malformations and with normal US biometric findings were selected for an FLV normative curve. FLV measurements obtained at pathologic examination with an immersion method were compared with MR FLV measurements in 11 fetuses. MR FLV values in 16 fetuses with thoracoabdominal malformations were compared with the normative curve. RESULTS: Normal FLV increased with gestational age as a power curve; the spread of values increased with age. Interobserver correlation was excellent (R(2) = 0.96). FLV measurements at MR imaging were 0.90 times those at pathologic examination. A constant ratio (0.78) between FLV on the left and right sides was observed. No significant difference in FLV was observed between fetal presentations. Normal FLV was observed in all fetuses with cystic adenomatoid malformations and in four of six with oligohydramnios. Lowest FLV values were observed in fetuses with diaphragmatic hernia. CONCLUSION: In fetuses with normal lungs, FLV distribution against gestational age is easily assessed in utero with fast spin-echo T2-weighted MR imaging. These preliminary findings illustrate the potential for comparing FLV measurements in fetuses at risk of lung hypoplasia with normative values. 相似文献
73.
A case of gastric pneumatosis is described in a 6 month old girl with Down syndrome. Plain abdominal radiographs showed a radiolucent rim within the gastric wall and a dilated stomach. Ultrasonography showed diffuse echoic streaks of air in the gastric wall, pneumobilia and gastroduodenal dilatation. Upper GI series showed duodenal stenosis. Gastric pneumatosis (air within the gastric wall), is an unusual radiographic finding. It may be of mechanical or inflammatory origin or, in some rare cases, remain unexplained. 相似文献
74.
Certain misleading appearances are peculiar to pediatric uroradiology. The most frequently encountered pitfalls are related to the bladder, to vesicoureteral reflux, and to the duplicated collecting system. The bi-chambered nature of the child's bladder, and the rapid settling of contrast material to the most dependent portion causes many pitfalls in diagnosis. When the child is prone, normal ureters may seem to be ectopic, and ureteroceles may become invisible. When the child is supine, the volume of urine in the bladder may be grossly under-estimated. Reflux can mimic function at urography. The dynamic nature of reflux leads to under-estimation of its presence and degree on the IVP and static cystogram. Reflux into an already dilated system can lead to over-estimation of its degree. Aberrant micturition with rapid refilling of the bladder can simulate incomplete emptying. The diagnosis of ectopic ureterocele is based on indirect evidence. Any condition that affects the urinary apparatus in the same way will have a similar appearance. A huge ureterocele may have a small ureter, and massive reflux into a lower pole ureter may make the diagnosis of duplication difficult. Ureterocele lookalikes, and effacement or intussusception of the ureterocele are cystographic pitfalls. Lower pole ureteropelvic junction obstruction and Wilms tumor in the lower portion of a kidney can have surprisingly similar appearances. 相似文献
75.
Kosuke Izumi Avni B. Santani Matthew A. Deardorff Holly A. Feret Tanya Tischler Brian D. Thiel Surabhi Mulchandani Catherine A. Stolle Nancy B. Spinner Elaine H. Zackai Laura K. Conlin 《American journal of medical genetics. Part A》2013,161(1):166-171
Prader–Willi syndrome is caused by the loss of paternal gene expression on 15q11.2–q13.2, and one of the mechanisms resulting in Prader–Willi syndrome phenotype is maternal uniparental disomy of chromosome 15. Various mechanisms including trisomy rescue, monosomy rescue, and post fertilization errors can lead to uniparental disomy, and its mechanism can be inferred from the pattern of uniparental hetero and isodisomy. Detection of a mosaic cell line provides a unique opportunity to understand the mechanism of uniparental disomy; however, mosaic uniparental disomy is a rare finding in patients with Prader–Willi syndrome. We report on two infants with Prader–Willi syndrome caused by mosaic maternal uniparental disomy 15. Patient 1 has mosaic uniparental isodisomy of the entire chromosome 15, and Patient 2 has mosaic uniparental mixed iso/heterodisomy 15. Genome‐wide single‐nucleotide polymorphism array was able to demonstrate the presence of chromosomally normal cell line in the Patient 1 and trisomic cell line in Patient 2, and provide the evidence that post‐fertilization error and trisomy rescue as a mechanism of uniparental disomy in each case, respectively. Given its ability of detecting small percent mosaicism as well as its capability of identifying the loss of heterozygosity of chromosomal regions, genome‐wide single‐nucleotide polymorphism array should be utilized as an adjunct to the standard methylation analysis in the evaluation of Prader–Willi syndrome. © 2012 Wiley Periodicals, Inc. 相似文献
76.
Shoshana Peller Joel Sayfan Yeheskel Levy Jan Oland Rivka Yona Suzana Kaufman Ruben Orda 《Journal of surgical oncology》1994,56(2):98-101
To determine the effect of perioperative blood transfusion on immunological parameters, T cells, T-cell subsets, and concanavalin A-induced suppression were measured in 25 patients with colorectal and breast cancer. During the operation, 15 patients received autologous blood and 10 patients had homologous transfusion. The immunological status was again determined after curative surgery. Before surgery, normal percentage of T lymphocytes, decreased ratios of helper/suppressor cells, and impaired con A-induced suppression were found. Following the operation, the helper and suppressor cell percentages reversed to normal, whereas the con A-induced suppression remained impaired. This change was significantly more pronounced in patients who received autologous blood transfusion than in the other group. Autotransfusion has an impact on immune parameters that might prove less detrimental to the clinical outcome in oncologic surgery than homologous transfusion. © 1994 Wiley-Liss, Inc. 相似文献
77.
Anna Durbin Frank Sirotich Tony Antoniou Kay Roesslein Janet Durbin Yona Lunsky 《AIDS care》2016,28(7):878-883
While community-based mental health services play an important role in caring for persons with HIV (human immunodeficiency virus) and co-existing mental health disorders, the extent to which their support needs are addressed in this setting is unknown. Accordingly, we examined if HIV infection was associated with unmet support needs among men living with and without HIV receiving community mental health care. This cross-sectional study examined 215 men (135 living with HIV and 80 without HIV) receiving case management services in urban Ontario. Using the Camberwell Assessment of Need, we ascertained the prevalence of support needs in 13 domains grouped into three clusters: Basic needs (accommodation, food, benefits, and money management); self-care/functional needs (daytime activities, self-care, and looking after the home); and health/safety needs (physical, psychological distress, psychotic symptoms, safety to self, and safety to others). We used generalized estimating equations with a logit link to examine the association between HIV and unmet need in each domain. Compared to HIV-negative men, men with HIV were more likely to have mood and concurrent disorders, and intellectual and developmental disabilities. Following multivariable analyses, men with HIV had greater unmet needs related to food (odds ratio?+?95% confidence interval: 9.36 (4.03, 21.75), p?<?0.001); money (OR: 1.90 (1.04, 3.47), p?=?0.036) [basic need domains]; psychological distress (OR: 2.39 (1.68, 3.41), p?<?0.001); drug use (OR: 5.10 (2.16, 12.08) p?<?0.001); and safety to self (OR: 3.35 (1.51, 7.52), p?<?0.003) [health and safety domains]. Despite living in a setting with universal health insurance, men with HIV receiving community mental health support had greater unmet need in basic and health domains than HIV-negative men receiving such support. Further research is required to develop and evaluate interventions to best support community-dwelling persons with HIV and mental health disorders. 相似文献
78.
Erin K. Willits Miguel A. Park Martha F. Hartz Cathy D. Schleck Amy L. Weaver Avni Y. Joshi 《Mayo Clinic proceedings. Mayo Clinic》2018,93(10):1423-1430
Objective
To determine the incidence and temporal trends of food allergies.Patients and Methods
We performed a historical cohort study to describe the epidemiology of food allergies among residents of all ages in Olmsted County, Minnesota, during a 10-year period from January 2, 2002, through December 31, 2011, using the Rochester Epidemiology Project database. Overall incidence and trends in biannual incidence rates over time were evaluated.Results
During the 10-year study period, 578 new cases of food allergies were diagnosed. The average annual incidence rate was significantly higher among males compared with females (4.1 [95% CI, 3.6-4.5] vs 3.0 [95% CI, 2.7-3.4]; P<.001; per 10,000 person-years; 3.6 per 10,000 person-years overall). The pediatric incidence rate of food allergy increased from 7.0 (95% CI, 6.2-8.9) to 13.3 (95% CI, 10.9-15.7) per 10,000 person-years between the 2002-2003 and 2006-2007 calendar periods and then stabilized at 12.5 and 12.1 per 10,000 person-years in the last 2 calendar periods. Milk, peanut, and seafood were the most common allergen in infancy, in children between ages 1 and 4 years, and in the adult population, respectively.Conclusion
This is one of the first population-based studies to examine the temporal trends of food allergies. The incidence of food allergies increased markedly between 2002 and 2009, with stabilization afterward. Additional longitudinal studies are warranted to assess for epidemiological evidence of changes in food allergy incidence with changing recommendations for allergenic food introduction. 相似文献79.
Marina Colombani Mathilde Ferry Catherine Garel Marie Cassart Alain Couture Laurent Guibaud Fred Avni Guillaume Gorincour 《Pediatric radiology》2010,40(7):1215-1221
Background
It has been described that both the colon and distal ileum present with a physiological hypersignal on T1-weighted sequences during the second and third trimesters of pregnancy because of their protein-rich meconium content, it was unclear whether the normal characteristics that have been described on fetal MRI can be applied to gastrointestinal (GI) obstructions.Objective
To analyse the localisation value of T1 hypersignal within dilated bowel loops in fetuses with gastrointestinal tract obstruction.Materials and methods
A retrospective 4-year multicentre study analysing cases of fetal GI obstruction in which MRI demonstrated T1 hypersignal content in the dilated loops. Data collected included gestational age (GA) at diagnosis, bowel appearance on US, CFTR gene mutations and amniotic levels of gastrointestinal enzymes. The suggested prenatal diagnosis was eventually compared to postnatal imaging and surgery.Results
Eleven patients were included. The median GA at US diagnosis was 23 weeks (range 13–32). In eight cases there was a single dilated loop, while several segments were affected in three. The median GA at MRI was 29 weeks (range 23–35). One case presented with cystic fibrosis mutations. Final prenatally suspected diagnoses were distal ileal atresia or colon in nine cases and proximal atresia in two. Postnatal findings were proximal jejunal atresia in nine cases and meconium ileus in two. In five cases the surgical findings demonstrated short bowel syndrome.Conclusion
In cases of fetal occlusion, T1 hypersignal should not be considered as a sign of distal ileal or colonic occlusion. The obstruction may be proximal, implying a risk of small bowel syndrome, which requires adequate parental counselling. 相似文献80.