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BackgroundOsteoblasts and osteoclasts are known to express Ang II type I (AT1) receptor in cell cultures, suggesting the existence of local renin-angiotensin system (RAS) in bone. This study was designed to investigate the effects of losartan as AT1 receptor blocker on ovariectomized rats' femur.MethodsLosartan (5 mg/kg/day) was administered via oral gavage for 8 weeks. Bone mineral density (BMD) was measured using dual energy X-ray absorptiometry, while tensile and three-point bending tests were performed for evaluation of biomechanical properties of bone. The trabecular porosity was analyzed by scanning electron microscopy.ResultsThere was a significant decrease in BMD values of ovariectomized rats' femurs which were reversed by losartan treatment. According to tensile test results, ultimate tensile strength and strain values of losartan treated ovariectomized rats' femurs increased and decreased, respectively, when compared to that of ovariectomized animals. Losartan treatment also caused a significant recovery in flexural strength and modulus parameters regarding respective control values, which mean losartan treated ovariectomized rats' femur had more force tolerance until break than ovariectomized rats' femur. Quantitative microscopic analysis showed larger trabecular porosity in ovariectomized rats than control rat femurs and it was significantly decreased after losartan treatment.ConclusionBlockage of AT1 receptor increased strength, mass and trabecular connections of ovariectomized rat femurs. Therefore, it is tempting to speculate that drugs, including AT1 receptor blockers, may be used for the treatment of osteoporosis or reduction of its detrimental effects in the future.  相似文献   
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Prominent ear deformity is a common congenital ear deformity. Prominent ear deformity includes components such as valgus of concha, failure of scaphal folding, conchal hypertrophy, and prominent lobule. The deformity and the elastic properties of the ear cartilage determine the method of surgical correction in each case. Concha-mastoid suture, conchal excision, and posterior auricular muscle excision are different treatment options for mild to severe cases of conchal hypertrophy and valgus deformity. In this article we present a method of conchal excision, combined with a posterior auricular muscle flap, to repair severe conchal hypertrophy or valgus deformity. Six patients (11 ears) were operated on using this method. The results obtained were satisfactory. Postoperative results at 6 months were satisfactory in all patients. The smoothness and the natural appearance of the conchal bowls were notable in all patients. In contrast to the early methods of utilizing the posterior auricular muscle by transposing to the scapha or excising, its usage as a muscle flap for conchal hypertrophy and valgus deformity may be a promising option for the future.  相似文献   
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BACKGROUND AND AIM: The proximal isovelocity surface area (PISA), which is the zone of flow convergence appearing on the left ventricular septal surface where flow approaching the defect accelerates, allows quantitative estimation of ventricular septal defect (VSD) flow and defect area on colour Doppler imaging. In the present study, the clinical applicability and reliability of the PISA method in assessing the amount of left-to-right shunting in patients with VSDs were evaluated. PATIENTS AND METHODS: Fifty-eight patients aged 0.25 to 15 years (mean age 4.3+/-4.4 years) with VSDs were prospectively studied. Maximum PISA radius in peak systole (r), peak velocity (V(max)) and velocity time integral (VTI(VSD)) of flow through the VSD were measured. In addition, peak VSD flow (2pir(2) Nyquist limit [NL]), amount of left-to-right shunting (Qp-Qs = heart rate x [2pir(2) x NL x VTI(VSD)]/V(max)) and defect area ([2pir(2) x NL]/V(max)) were calculated. RESULTS: There were significant positive correlations between Qp-Qs values calculated by PISA and other spectral Doppler methods using the cross-sectional area, as well as the VTI of pulmonary-aortic (r=0.73, P<0.001) or mitral-tricuspid (r=0.58, P<0.001) flows and cardiac catheterization (20 patients, r=0.82, P<0.001). PISA-derived left-to-right-shunting discriminated moderate to large defects from small defects, which were classified according to the catheter-derived Qp/Qs ratio (2 or greater versus less than 2; P=0.001) or clinical evaluation (P<0.001). CONCLUSIONs: The present study demonstrated that the PISA method is a reliable semiquantitative method to determine the amount of left-to-right shunting of VSDs and to discriminate moderate to large defects from small defects. Consequently, this method may serve as a simple and useful adjunct to conventional spectral Doppler methods in the noninvasive assessment of patients with VSDs.  相似文献   
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Heterotopic gastric tissue in the gallbladder is an extremely rare condition. There is not any specific clinical or laboratory finding and correct diagnosis is not possible before histopathological examination. Preoperative diagnosis usually resembles a polypoid Lesion or a fixed gallstone. We reported a 34-year-old female patient with heterotopic gastric mucosa in the gallbladder associated with congenital hip dysplasia and kidney agenesis. Laparoscopic cholecystectomy was performed and histopathology of the resected specimen showed that the "polyp" consisted of heterotopic gastric mucosa with glands of body and fundic type. Some cases of heterotopia in the gallbladder come from metaplasia, and may be one of the causes of gall bladder cancer. We discussed the clinical and histologic features of heterotopic gastric tissues and reviewed reported cases in the literature.  相似文献   
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