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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   
73.
Abstract   A case of aortopulmonary window associated with anomalous origin of the right coronary artery from the pulmonary artery in a four-month-old boy is reported in this paper with a different method of repair. In this patient, surgical repair was done by transferring the right coronary artery from the pulmonary artery to the aorta at the aortopulmonary window side. The defect at the pulmonary artery was repaired by a pericardial patch, so no other secondary opening was used for the aorta in order to reimplant the coronary artery .  相似文献   
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BACKGROUND/AIMS: Dieulafoy's lesions are uncommon sources of upper gastrointestinal tract bleeding. Endoscopists must be aware of these lesions when evaluating patients with upper gastrointestinal tract bleeding. METHODOLOGY: The aim of this study is to analyze the results of active bleeding or recurrently bleeding Dieulafoy's lesions treated either by endoscopic injection therapy (EIT) or endoscopic band ligation (EBL). Fifteen patients who had active bleeding due to Dieulafoy's lesions were evaluated retrospectively with respect to demographic properties, comorbidities, endoscopic therapy procedures, and the success rate of the procedure. RESULTS: The incidence of Dieulafoy's lesions was 4.5% in all cases of upper gastrointestinal tract bleeding. Among the 15 patients there were nine men and six women with a median age of 52 years (25-84 years). Eleven of these lesions were located in the stomach, two were in the duodenum, and two were in the distal esophagus. Eight patients were initially treated by EIT and seven patients had EBL therapy. There was no recurrent bleeding in any of the patients treated with EBL, but five patients (62.5%) treated with EIT bled again and were treated secondarily with EBL. Two of these patients required surgical intervention and one died on the 15th day of surgery due to myocardial infarction. No endoscopy-related complications were detected. CONCLUSIONS: Endoscopic methods should be the first choice in treating bleeding Dieulafoy's lesions. Both EIT and EBL are successful methods for achieving initial hemostasis. However, EIT therapy has a higher re-bleeding rate. EBL is a safe and effective method for the treatment of bleeding Dieulafoy's lesions.  相似文献   
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Ewing sarcomas are most commonly located in bone, while extraskeletal involvement of the retroperitoneum is extremely rare. We describe the radiologic and pathological findings in an adult patient with retroperitoneal extraskeletal Ewing sarcoma.  相似文献   
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The aim of this study was to determine whether left renal vein (LRV) variation is associated with pelvic varices and left ovarian vein (LOV) reflux. Routine abdominal multidetector-row computed tomography scans of 324 women without symptoms of pelvic congestion syndrome were analyzed. Presence and type of LRV variants (circumaortic [CLRV] or retroaortic [RLRV]) were recorded. Diameters of the LRV, ovarian veins (OVs), and parauterine veins were measured and a specific LRV diameter ratio was calculated for each patient. Presence and severity of pelvic varices and LOV reflux were noted. Pelvic varices were detected in 59 (18%) of the total of 324 women, in 7 (37%) of the 19 women with RLRVs, in 7 (29%) of the 24 women with CLRVs, and in 45 (16%) of the 281 women with normal LRVs. The frequency of pelvic varices in the women with LRV variation was significantly higher than that in the group with normal LRV anatomy (33 vs. 16%; p=0.009). The frequency of pelvic varices in the women with RLRVs was also significantly higher than that in the group with normal LRV anatomy (p=0.02). LRV diameter ratio was correlated with presence of pelvic varices and presence of LOV reflux (p=0.0001 for both). This study revealed an association between pelvic varices and LRV variations in a population of predominantly multiparous women. The preliminary results of this study were presented as an electronic poster at the ECR (European Congress of Radiology) conference, 3–7 March 2006 in Vienna, Austria.  相似文献   
78.
Restless leg syndrome (RLS) is an abnormal sensation disorder. Defining the syndrome is difficult. It is transmitted autosomal dominant genetically, is especially prevalent in the lower limbs, and is seen in both genders. In the differential diagnosis of RLS, nocturnal leg cramps, akathisia, peripheral neuropathy, entrapment neuropathy, and vascular disease (for example, deep vein thrombosis) should be considered. A 52-year-old woman was admitted to our clinic with signs of paresthesia, she had abnormal sensation disorder in both legs and the right arm, which she had difficulty defining. She had applied to another center with the same complaints and had been evaluated as entrapment neuropathy, carpal tunnel syndrome, and/or peripheral neuropathy. Her electromyographic examination carried out by us was normal. The history, neurological examination findings, and results of standard laboratory analyses provided a diagnosis of idiopathic RLS. After the diagnosis of RLS in the proband, we questioned other family members. Her large family had 63 members, 35 males, and 28 females. Of 63 members, 17 also had an RLS diagnosis.  相似文献   
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INTRODUCTION: The management of epidural hematoma is classified into surgical or conservative treatment according to clinical and radiologic parameters. In the recent years, the number of paper suggesting conservative management has been increasing. The experimental works that have been performed are based on especially the effects of epidural hematomas. Basic pathophysiologic factors on ischemia result of brain trauma are based on biochemical mediators. Nitric oxide (NO) and malondialdehyde (MDA) are the substances that play important roles in brain damage after trauma. MATERIAL AND METHOD: In this study, 36 rats are divided into three groups (n = 12/group). Epidural hematoma was achieved by 0.1 ml autolog blood in rat epidural space with balloon model. Early and late phase biochemical effects on parenchyma of epidural hematoma operated in a volume which neither alters intracranial pressure (ICP) nor creates shift effect were observed. Biochemical changes of NO and MDA levels were examined in each of three experimental groups. RESULTS: NO values increased significantly in the early group (6 hours) compared with those in the control group. Difference of NO values between the control and late groups was not significant. An increase has been found in MDA values in the control group compared with those in the early group. MDA values of the late group (30 days) were closer to that of the control group. CONCLUSION: In this study, considering biochemical results, we have found that conservative volumes which neither increase ICP nor cause brain shift do not lead to permanent changes on brain.  相似文献   
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