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91.
46,XX testicular disorder of sex development (46,XX TDSD) is a relatively rare condition characterised by the presence of testicular tissue with 46,XX karyotype. The present study aims to reveal the phenotype to genotype correlation in a series of sex-determining region Y (SRY)-positive 46,XX TDSD cases. We present the clinical findings, hormone profiles and genetic test results of six patients with SRY-positive 46,XX TDSD and give the details and follow-up findings of our three of previously published patients. All patients presented common characteristics such as azoospermia, hypergonadotropic hypogonadism and an SRY gene translocated on the terminal part of the short arm of one of the X chromosomes. Mean ± standard deviation (SD) height of the patients was 164.78 ± 8.0 cm. Five patients had decreased secondary sexual characteristics, and three patients had gynaecomastia with varying degrees. Five of the seven patients revealed a translocation between protein kinase X (PRKX) and inverted protein kinase Y (PRKY) genes, and the remaining two patients showed a translocation between the pseudoautosomal region 1 (PAR1) of X chromosome and the differential region of Y chromosome. X chromosome inactivation (XCI) analysis results demonstrated random and skewed XCI in 5 cases and 1 case, respectively. In brief, we delineate the phenotypic spectrum of patients with SRY-positive 46,XX TDSD and the underlying mechanisms of Xp;Yp translocations.  相似文献   
92.
Our current understanding of emmetropisation and myopia development has evolved from decades of work in various animal models, including chicks, non-human primates, tree shrews, guinea pigs, and mice. Extensive research on optical, biochemical, and environmental mechanisms contributing to refractive error development in animal models has provided insights into eye growth in humans. Importantly, animal models have taught us that eye growth is locally controlled within the eye, and can be influenced by the visual environment. This review will focus on information gained from animal studies regarding the role of optical mechanisms in guiding eye growth, and how these investigations have inspired studies in humans. We will first discuss how researchers came to understand that emmetropisation is guided by visual feedback, and how this can be manipulated by form-deprivation and lens-induced defocus to induce refractive errors in animal models. We will then discuss various aspects of accommodation that have been implicated in refractive error development, including accommodative microfluctuations and accommodative lag. Next, the impact of higher order aberrations and peripheral defocus will be discussed. Lastly, recent evidence suggesting that the spectral and temporal properties of light influence eye growth, and how this might be leveraged to treat myopia in children, will be presented. Taken together, these findings from animal models have significantly advanced our knowledge about the optical mechanisms contributing to eye growth in humans, and will continue to contribute to the development of novel and effective treatment options for slowing myopia progression in children.  相似文献   
93.
Joint instability and cartilage trauma have been previously studied and identified as key mediators in the development of posttraumatic osteoarthritis (PTOA). The purpose of this study was to use an in vivo model to compare the effect of joint instability, caused by the rupture of the anterior cruciate ligament (ACL), versus cartilage compression. In this study, mice were subjected to cyclical axial loads of twelve Newtons (N) for 240 cycles or until the ACL ruptured. One and eight weeks after this procedure, knees were sectioned coronally and evaluated for osteoarthritis by histology. Using a scoring scale established by [Pritzker K, Gay S, Jimenez S, et al. (2006): Osteoarthritis Cartilage 14:13–29], the articular cartilage across each surface was scored and combined to produce a total degeneration score. The ACL‐ruptured group had a significantly greater total degeneration score than either control or compression treated joints at 1 and 8 weeks. Additionally, only sections from ACL‐ruptured knees consistently showed synovitis after 1 week and osteophyte formation after 8 weeks. Thus, it appears using that ACL rupture consistently creates a severe osteoarthritis phenotype, while axial cartilage compression alone does not appear to be an appropriate method of inducing PTOA in vivo. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:318–323, 2014.  相似文献   
94.
95.

Aim

Over the past 2 decades, transcatheter occlusion of patent ductus arteriosus (PDA) with coils and the duct occluders evolved to be the procedure of choice. A new device, the Occlutech PDA® occluder (ODO) device has been designed. Herein, we aimed to evaluate the characteristics and short‐term results of patients who underwent transcatheter closure of PDA using the ODO.

Methods

We reviewed the clinical records of 60 patients from different centers in Turkey between December 2013 and January 2016. The medical records were reviewed for demographic characteristics and echocardiographic findings. Device size was selected on the narrowest diameter of PDA.

Results

The median patient age was 2.5 years (6 months–35 years), and median PDA diameter was 2.5 mm (1.2–11 mm). Fifty‐eight of 60 patients (96.6%) had successful ODO implantation. The occlusion rates were 37/58 (63.7%) at the end of the procedure, 51/58 (87.9%) at 24–48 hours post‐procedure, and 57/58 (98.2%) on echocardiography at a median follow‐up of 7.6 months.

Conclusion

Our results indicate that transcatheter closure of PDA using the ODO is effective. Larger studies and longer follow‐up are required to assess whether its shape and longer length make it superior to other duct occluders in large, tubular, or window‐type ducts. (J Interven Cardiol 2016;29:325–331)
  相似文献   
96.
We analyzed the postoperative short- and mid-term outcomes of a series of patients with annuloaortic ectasia who underwent a modified Bentall operation in our clinic from September 2000 through March 2006. The study included 44 patients. Their average age was 53.4 +/- 14.1 years. The underlying disease was degenerative aortic aneurysm in 42 patients (95.5%) and acute aortic dissection in 2 patients (4.5%). Six patients (13.6%) had Marfan phenotype. Aortic insufficiency was moderate in 30 patients (68.2%) and severe in 14 patients (31.8%). In our modification of the Bentall technique, we completed the resection of the aortic root while leaving 5 to 10 mm of native aortic wall tissue to support the anastomosis. A long piece of Teflon felt (width, 0.5-1 cm) was laid on the annulus, and nonpledgeted 2-0 polyester sutures were passed in turn through the Teflon felt, the preserved aortic tissue, and the aortic annulus. A thin piece of Teflon felt was also used in the coronary artery reimplantation sites. Fibrin glue was routinely applied to all anastomoses. There were no intraoperative deaths. One patient died in the hospital after surgery for acute type I aortic dissection. Another patient died 1 year after the operation from prosthetic-valve endocarditis. No patient required surgical correction of excessive postoperative bleeding. Kaplan-Meier curves showed overall survival of 0.94 (95% confidence intervals, 0.9-0.99). We consider our approach an easy, effective way to minimize bleeding from the anastomoses and at the aortic root--a common challenge in aortic surgery.  相似文献   
97.
Aim: To determine the prevalence of vitamin D hypovitaminosis among obese and overweight schoolchildren.Design: A cross−sectional population based sample.Methods: In a cross−sectional study, 301 students (177 girls and 124 boys) aged 11−19 years were selected by multistage stratified sampling design. Subjects were classified according to their body mass index as obese, overweight and normal. Serum 25−hydroxyvitamin D (25−OHD), intact parathyroid hormone (iPTH) and alkaline phosphatase (ALP) were measured in late winter months. Vitamin D deficiency was defined as a 25−OHD 20 ng/ml.Results: The prevalence of hypovitaminosis D was found as 65% in all students. Vitamin D deficiency was found in 12% and insufficiency in 53% of all students. Vitamin D deficiency in female students was about two times more common than in males. In obese and overweight schoolchildren with hypovitaminosis D, serum 25−OHD levels decreased as BMI increased. There were no correlations between serum 25−OHD and ALP and iPTH levels.Conclusion: Vitamin D deficiency and insufficiency are common in obese and overweight schoolchildren, especially in girls. Obesity could be a risk factor in terms of hypovitaminosis D in adolescents. Vitamin D supplementation should be administered particularly to adolescent girls.Conflict of interest:None declared.  相似文献   
98.
99.
The term frontotemporal lobar degeneration (FTLD) refers to a group of neurodegenerative disorders that target the frontal and temporal lobes. It accounts for approximately 10 % of pathologically confirmed dementias but has been demonstrated to be as prevalent as Alzheimer’s disease in patients below the age of 65. The 3 major clinical syndromes associated with FTLD include behavioral variant frontotemporal dementia, semantic and nonfluent variants of primary progressive aphasia. The more recently introduced term logopenic variant appears to represent an atypical form of Alzheimer’s disease in the majority of cases. The neuropathology underlying these clinical syndromes is very heterogeneous and does not correlate well with the clinical phenotype. This causes great difficulties in early and reliable diagnosis and treatment of FTLD. However, significant advances have been made in recent years via the application of magnetic resonance imaging and positron emission tomography imaging methods as biomarkers. The current review aims to provide a synopsis on the value of magnetic resonance imaging-based and molecular imaging procedures in FTLD.  相似文献   
100.
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