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51.
52.
Patients with multiple hereditary exostoses (MHE) often develop leg length discrepancies and limb alignment deformity around the knee as part of the natural course of the disease. Limb alignment deformity occurring post-resection of an osteochondroma has been described in one case report and only pertaining to the proximal medial tibia location. Here we describe the case of 2 patients with MHE, a 7-year-old female who underwent resection of distal femur and proximal tibia osteochondromas and a 9-year-old female who had a distal femur osteochondroma resected. Both patients developed rapidly progressive valgus knee deformity requiring surgical intervention. Excision of osteochondromas near the physis of a skeletally immature patient can cause overgrowth from the involved side of the growth plate resulting in a rapidly progressing unilateral coronal plane deformity. Surgeons should be aware of this potential complication and closely follow growing patients with serial alignment radiographs and counsel the family regarding the potential of acquired limb deformity and subsequent surgeries.  相似文献   
53.
Background: In recent years, numerous scientific publications have endorsed the superiority of the ProSeal? laryngeal mask airway (PLMA) over the Classic? laryngeal mask airway (cLMA) in adults, children, and infants. The PLMA forms a better seal for both the respiratory and gastrointestinal tracts, provides easier access to the gastrointestinal tract, and exerts lower mucosal pressures for a given seal pressure. This study aims to determine whether this superiority can also be observed for the size 1 PLMA used in anesthetized neonates and infants with positive pressure ventilation. Methods: Sixty consecutive neonates and infants undergoing elective surgical procedures were randomized to airway management with the size 1 PLMA or cLMA. For all patients, we recorded ease of insertion, effective airway time, number of placement attempts, oropharyngeal leak pressure, fiberoptic position, audible leaks, mask displacement, number of reinsertions during maintenance, gastric insufflation, and frequency of blood stain. Results: Ease of insertion, successful insertion in <3 attempts, fiberoptic position of the airway tube, and frequency of blood stain were similar in both groups. Effective airway time was lower for the PLMA group (30.5 vs 35.6 s). Oropharyngeal leak pressure was higher with the PLMA (32.9 vs 22.2 cm H2O, P < 0.001) and gastric insufflation less common (0% vs 6%, P = 0.492). There were fewer mask displacements during maintenance of anesthesia with the PLMA (0% vs 26.7%, P < 0.001). Mask reinsertion was not necessary during maintenance of anesthesia with the PLMA, although it was necessary in 14 cases in the cLMA group (0% vs 46%, P < 0.001). Audible leaks were less common with the PLMA (0% vs 46%, P < 0.001). Conclusions: We conclude that the size 1 PLMA is a stable, safe, and efficacious airway control device during neonatal and infant anesthesia, allowing higher peak airway pressure during positive pressure ventilation, with fewer mask displacements and gastric insufflations than the cLMA.  相似文献   
54.
The α4 polypeptide is a testis-specific isoform of the catalytic subunit of the Na,K-ATPase, which is essential for sperm motility and fertility. In the present study, we have investigated the regulation of activity of the α4 isoform and the relevance of this event for sperm capacitation. We have performed this by taking advantage of the selective high affinity of α4 for the inhibitor ouabain. Our results show that ouabain-sensitive hydrolysis of ATP and uptake of (86)Rb, corresponding to the enzymatic and ion transport activities of α4, respectively, increased during sperm capacitation in a time-dependent manner. Specific labeling of α4 with the fluorescent indicator bodipy-ouabain and immunoblot analysis of biotinylated and streptavidin-precipitated sperm plasma membrane proteins indicated a capacitation- and time-dependent rise in levels of active α4 isoform at the sperm surface. Ouabain inhibition of α4 blocked the increase in total sperm motility and the hyperactive motility pattern characteristic of sperm capacitation. Moreover, interference of α4 activity with ouabain partially prevented the intracellular decrease in Na(+) and the plasma membrane hyperpolarization that typically accompany sperm capacitation. In contrast, ouabain inhibition of α4 did not affect the spontaneous sperm acrosomal reaction following capacitation. Together, these results demonstrate that Na,K-ATPase α4 activity is up-regulated during sperm capacitation through mechanisms that involve both increases in molecular activity and levels of α4 at the sperm plasma membrane. This increase in α4 activity helps maintain the changes in motility that are associated with sperm capacitation, emphasizing the biologic relevance of the Na,K-ATPase α4 isoform in sustaining sperm function.  相似文献   
55.
Biliary atresia is the most common indication for liver transplantation in the pediatric age group. The Kasai portoenterostomy has become established as the primary treatment for biliary atresia. If portoenterostomy fails, death before 2 years of age is likely without liver transplantation. The most common multiple malformation syndrome associated with biliary atresia is polysplenia syndrome, which forms a constellation of defects of body symmetry, splenic development and vascular anomalies, including situs inversus, polysplenia and others. The situs inversus was formerly considered an absolute contraindication for liver transplantation. Recently however, several case reports have been published suggesting that neither situs inversus nor this particular subset of vascular abnormalities should be considered contraindications to liver transplantation. We present one case of liver transplantation performed in patient with biliary atresia, situs inversus and polysplenia. This is the first report described in Spain for a liver transplant in a child with biliary atresia plus situs inversus.  相似文献   
56.
57.
Duplication of the male urethra is an uncommon congenital malformation. The majority of cases are diagnosed during infancy, and are detected by observing two urethral meatus, or by the appearance of some form of complication, normally of an obstructive nature. Micturitional cystourethrography is an essential test, both in confirming diagnosis of this pathology, and in determining the type of urethral duplication. Excretory urography is also recommended due to its association with other possible urological and extra-urological congenital disorders. Treatment is based on the patient's clinical symptoms, with a waiting period considered advisable for asymptomatic cases. Here we present a case of incomplete urethral duplication, diagnosed from a bladder outlet obstruction, secondary to stenosis of the urethra, which was treated with an endoscopic urethrotomy and distal septotomy, obtaining excellent clinical results.  相似文献   
58.
Because of the extraperitoneal location, generally used for renal grafting, intraperitoneal urine leaks are a rare complication after transplantation. We report a patient on peritoneal dialysis who developed ascites, abdominal pain, anuria and shock suddenly after renal transplantation. The patient was immediately taken back to the operating room. An abnormal implantation of ureter into the peritoneum overlying the bladder when carrying out an unstented parallel incision extravesical ureterone-ocystostomy was identified. After correcting ureter implantation the patient had immediate diuresis, renal function rapidly improved, with no further complications. Contributing causes were poor exposure, thickened peritoneum secondary to recurrent peritonitis, and the presence of residual peritoneal dialysis fluid.  相似文献   
59.
BACKGROUND: Glomerular filtration rate (GFR) in humans and animals might be determined with precision by measuring the clearance of an ideal marker, such as inulin. However, the use of inutest, an inulin analog, is limited by its cost and accessibility. The present study tested whether low calorie commercial sugar (LC sugar) can be used to measure GFR during normal and renal dysfunction. METHODS: Two groups of 6 male Wistar rats weighing 300 to 350 g were included. One group was treated with a daily dose of cyclosporine (CsA) 30 mg/kg subcutaneously for 7 days and the other group was formed by nontreated control rats. In one half of each group, GFR was evaluated by using inutest and in the other half by using LC sugar. GFR was also evaluated by using a wide LC sugar plasma concentration range in an additional group. RESULTS: In nontreated rats, the mean GFR evaluated with LC sugar was 2.2 +/- 0.1 mL/min. This value is equal to that obtained with inutest: 2.3 +/- 0.1 mL/min. CsA administration produced a significant reduction of renal blood flow and renal function. The GFR reduction induced by CsA was similarly determined by both LC sugar and inutest to be at 1.0 +/- 0.2 and 1.1 +/- 0.2 mL/min (P= NS), respectively. In addition, GFR did not change when LC sugar plasma concentration gradually increased. CONCLUSION: Our results show that in both normal and pathophysiologic conditions, LC sugar is a good marker of GFR similar to the gold standard inutest.  相似文献   
60.
Purpose: The aim of this study was to assess the effect of local melatonin administration on bone osseointegration around implants in rabbit tibiae. Material and Methods: Ten female, 6‐month‐old New Zealand rabbits were randomly divided into two groups: the experimental group, where five rabbits were treated with local application of melatonin (3 mg) to implant sites when placed into the rabbit tibia, and the control group, those who where without additive materials. Four weeks later, animals were sacrificed; tibiae were dissected from soft tissues and fixed in buffered formaldehyde, and then included in methacrylate. Histological sections were performed to be studied under light microscopy and analyzed morphometrically to evaluate the amount of bone to implant contact (BIC), trabecular area density, and cortical area density. One‐way analysis of variance test was used for statistical evaluation. p < .05 was considered to be significant. Results: Histological evaluation showed more trabecular reaction in the melatonin group. Morphometrical analysis showed a statistically significant increase in trabecular BIC in the melatonin group when compared with the control group (24.61% ± 2.87 vs 13.62% ± 1.44; p < .01). Cortical BIC was decreased in the melatonin group, without statistical significance (71.08 ± 3.63 vs 76.28 ± 2.57; p = 0.31). Trabecular area density was increased significantly in the melatonin group (8.68 ± 1.61 vs 4.02 ± 0.36; p < .05). Cortical area density was decreased significantly in the melatonin group (91.31 ± 1.6 vs 95.7 ± 0.5; p < .05). Conclusion: Within the limitation of this animal study, local melatonin application at the time of implant placement might induce more trabecular bone at implant contact and higher trabecular area density.  相似文献   
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