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331.
Five infertile women exposed to long-acting gonadotrophin-releasing hormone agonist (GnRHa) during early pregnancy were studied to assess the risks of embryotoxicity on the outcome of their pregnancies. All the patients were diagnosed as stage 3-4 endometriosis following laparoscopy. Long-acting GnRHa (3.75 mg) was given in the first 3 days of their preceding menstrual period. Four of the five patients had two GnRHa injections and the last patient had three GnRHa injections. All patients were advised to use a barrier contraception (condoms) throughout the treatment period. Since all complained of no bleeding following the initial injections, human chorionic gonadotrophin (beta-HCG) concentrations were tested in order to rule out any pregnancy. Ultrasonographic examinations were commenced routinely and all patients had amniocentesis at 16-18 weeks gestational age. Genetic analysis revealed a normal karyotype in all fetuses. All five pregnancies progressed to term without complication, and normal healthy infants were delivered. Although there are still no clear answers concerning teratogenic and hormonal effects of GnRHa exposure in pregnancy, our data may suggest that luteal function, genetic structure and pregnancy outcome are not adversely affected by GnRHa. Since possible subtle effects on fetal endocrine organs cannot be disregarded, close monitoring is still needed in GnRHa-exposed pregnancies.  相似文献   
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Summary  An 11-year-old female, presented with a cervical myelomeningocele. Interestingly, the myelomeningocele sac was seen to contain a meningioma. There are no aetiological factors in the embryogenetic period that would lead to such a combination of lesions. In our opinion, the meningioma appeared in a later period because of local factors.  相似文献   
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Background

The aim of present study was to evaluate the indications, complications and outcomes of acute peritoneal dialysis (APD) in neonates at a referral university hospital during the previous 8 years.

Methods

This retrospective analysis included a total of 52 newborn infants who underwent APD in a neonatal intensive care unit between January 2008 and March 2016. Demographic, clinical, laboratory and microbiological data were extracted from patients' medical files.

Results

The primary causes for requiring APD were acute tubular necrosis (n = 36, 69.2%), inborn error of metabolism (n = 10, 19.2%), congenital nephrotic syndrome (n = 2, 3.9%), bilateral polycystic kidney (n = 2, 3.9%), renal agenesis (n = 1, 1.9%), and obstructive uropathy (n = 1, 1.9%). The mean duration of APD was 8.7 ± 15.87 days (range: 1–90 days). Procedural complications were mainly hyperglycemia (n = 16, 47.1%), dialysate leakage (n = 7, 20.6%), peritonitis (n = 3, 8.8%), catheter obstruction (n = 3, 8.8%), bleeding at the time of catheter insertion (n = 2, 5.9%), catheter exit site infection (n = 2, 5.9%), and bowel perforation (n = 1 2.9%). There were 40 deaths (76.9%), mainly due to underlying causes. Ten of the 12 survivors showed full renal recovery, but mild chronic renal failure (n = 1) and proteinuria with hypertension were seen (n = 1) in each of remaining patients.

Conclusion

Peritoneal dialysis is an effective route of renal replacement therapy in the neonatal period for management of metabolic disturbances as well as renal failure. Although major complications of the procedure are uncommon, these patients still have a high mortality rate due to serious nature of the underlying primary causes.  相似文献   
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The present study was conducted to determine the effect on the distribution of stress with the use of short-post cores and over restorations composed of different materials. The restorative materials used were namely two different composite resin materials (Valux Plus and Tetric Flow), a polyacid-modified resin material (Dyract AP), and a woven polyethylene fiber combination (Ribbond Fiber + Bonding agent + Tetric Flow). Finite element analysis (FEA) was used to develop a model for the maxillary primary anterior teeth. A masticatory force of 100 N was applied at 148 degrees to the incisal edge of the palatal surface of the crown model. Stress distributions and stress values were compared using von Mises criteria. The tooth model was assumed to be isotropic, homogeneous, elastic, and asymmetrical. It was observed that the highest stress usually occurred in the cervical area of the tooth when Tetric Flow was used as the short-post core and over restoration material. The same maximum stress value was also obtained when Ribbond fiber + Tetric Flow material was used for the short-post core. The results of FEA showed that the mechanical properties and elastic modulus of the restorative material influenced the stresses generated in enamel, dentin, and restoration when short-post core restorations were loaded incisally. Resin-based restorative materials with higher elastic moduli were found to be unsuitable as short-post core materials in endodontically treated maxillary primary anterior teeth.  相似文献   
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OBJECTIVES/HYPOTHESIS: The primary objective of this study was to determine the relationship between chronic rhinosinusitis (CRS) and laryngopharyngeal reflux (LPR). We also investigated the diagnostic value of pepsin in nasal lavage by means of fluorometric assay as compared with 24-hour dual-probe pH monitoring. STUDY DESIGN AND METHODS: This is a controlled, prospective study from a retrospective dataset of 33 patients recruited for endoscopic sinus surgery between 2005 and 2006 in a tertiary care referral center (Hacettepe University Medical Center). All patients underwent 24-hour dual-probe pH monitoring and nasal lavage fluid investigation for pepsin. A fluorometric pepsin assay using casein-fluorescein isothiocyanate in nasal lavage fluid was used to detect LPR. The control group included 20 patients who were proven not to have sinusitis. RESULTS: A higher incidence of pharyngeal acid reflux events was found in patients with CRS (29 of 33, 88%) compared with the control patients (11 of 20, 55%). The difference was statistically significant (P = .01). The fluorometric pepsin assay was correlated to the results of 24-hour dual-probe monitoring for LPR diagnosis with a 100% sensitivity and 92.5% specificity. These data suggest that an association between CRS and LPR is present and that the detection of pepsin in nasal lavage fluid may provide a noninvasive and feasible method of LPR screening.  相似文献   
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Over the last decade tissue engineering has emerged as a key factor in bone regeneration within the field of cranio-maxillofacial surgery. Despite this in vivo analysis of tissue-engineered-constructs to monitor bone rehabilitation are difficult to conduct. Novel high-resolving flat-panel based volume CTs (fp-VCT) are increasingly used for imaging bone structures. This study compares the potential value of novel fp-VCT with conventional multidetector CT (MDCT) based on a sheep sinus floor elevation model. Calcium-hydroxyapatite reinforced collagen scaffolds were populated with autologous osteoblasts and implanted into sheep maxillary sinus. After 8, 16 and 24 weeks MDCT and fp-VCT scans were performed to investigate the volume of the augmented area; densities of cancellous and compact bone were assessed as comparative values. fp-VCT imaging resulted in higher spatial resolution, which was advantageous when separating closely related anatomical structures (i.e. trabecular and compact bone, biomaterials). Fp-VCT facilitated imaging of alterations occurring in test specimens over time. fp-VCTs therefore displayed high volume coverage, dynamic imaging potential and superior performance when investigating superfine bone structures and bone remodelling of biomaterials. Thus, fp-VCTs may be a suitable instrument for intraoperative imaging and future in vivo tissue-engineering studies.  相似文献   
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