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In this study, we aimed to compare the success and complications of flexible ureterorenoscopy (F-URS) with its advanced technology and the accomplished method of shock wave lithotripsy (SWL) in the treatment of lower pole stones smaller than 1 cm. One hundred and forty patients were randomized as 70 undergoing SWL (Group 1) and 70 undergoing F-URS (Group 2). Patients were evaluated by plain X-ray and urinary ultrasound 1 week and after 3 months following SWL. The same procedure was done for F-URS patients 1 week after surgery and after 3 months. Success rates were established the day following the procedure and after 3 months. Fragmentation less than 3 mm was considered success. Mean operative time was 44 ± 7.4 min for Group 2 and mean fluoroscopy duration was 51 ± 12 s. In F-URS group, all the patients were stone free after 3 months (100 %). Group 1 had 2.7 ± 0.4 sessions of SWL. Sixty-four patients were stone free in that group after 3 months (91.5 %). The procedure yielded significant success in FURS group, even though patients underwent SWL for 2.7 ± 0.4 sessions and F-URS for 1 session (p < 0.05). With higher success and similar complication rates, fewer sessions per treatment, and advances in technology and experience, we believe F-URS has a potential to be the first treatment option over SWL in the future.  相似文献   
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Although reduced working memory brain activation has been reported in several brain regions of cocaine‐dependent subjects compared with controls, very little is known about whether there is altered connectivity of working memory pathways in cocaine dependence. This study addresses this issue by using functional magnetic resonance imaging‐based stochastic dynamic causal modeling (DCM) analysis to study the effective connectivity of 19 cocaine‐dependent subjects and 14 healthy controls while performing a working memory task. Stochastic DCM is an advanced method that has recently been implemented in SPM8 that can obtain improved estimates, relative to deterministic DCM, of hidden neuronal causes before convolution with the hemodynamic response. Thus, stochastic DCM may be less influenced by the confounding effects of variations in blood oxygen level‐dependent response caused by disease or drugs. Based on the significant regional activation common to both groups and consistent with previous working memory activation studies, seven regions of interest were chosen as nodes for DCM analyses. Bayesian family level inference, Bayesian model selection analyses, and Bayesian model averaging (BMA) were conducted. BMA showed that the cocaine‐dependent subjects had large differences compared with the control subjects in the strengths of prefrontal–striatal modulatory (B matrix) DCM parameters. These findings are consistent with altered cortical–striatal networks that may be related to reduced dopamine function in cocaine dependence. As far as we are aware, this is the first between‐group DCM study using stochastic methodology. Hum Brain Mapp 35:760–778, 2014. © 2012 Wiley Periodicals, Inc.  相似文献   
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PURPOSE

This study was to evaluate the effect of grinding of the inner metal surface during the porcelain try-in stage on metal-porcelain bonding considering the maximum temperature and the vibration of samples.

MATERIALS AND METHODS

Ninety-one square prism-shaped (1 × 1 × 1.5 mm) nickel-chrome cast frameworks 0.3 mm thick were prepared. Porcelain was applied on two opposite outer axial surfaces of the frameworks. The grinding was performed from the opposite axial sides of the inner metal surfaces with a low-speed handpiece with two types of burs (diamond, tungsten-carbide) under three grinding forces (3.5 N, 7 N, 14 N) and at two durations (5 seconds, 10 seconds). The shear bond strength (SBS) test was performed with universal testing machine. Statistical analyzes were performed at 5% significance level.

RESULTS

The samples subjected to grinding under 3.5 N showed higher SBS values than those exposed to grinding under 7 N and 14 N (P<.05). SBS values of none of the groups differed from those of the control group (P>.05). The types of bur (P=.965) and the duration (P=.679) did not affect the SBS values. On the other hand, type of bur, force applied, and duration of the grinding affected the maximum temperatures of the samples, whereas the maximum vibration was affected only by the type of bur (P<.05).

CONCLUSION

Grinding the inner metal surface did not affect the metal-porcelain bond strength. Although the grinding affected the maximum temperature and the vibration values of the samples, these did not influence the bonding strength.  相似文献   
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INTRODUCTION

Atypical presentations of appendix have been reported including backache, left lower quadrant pain and groin pain from a strangulated femoral hernia containing the appendix. We report a case presenting an epigastric pain that was diagnosed after computed tomography as a perforated appendicitis on intestinal malrotation.

PRESENTATION OF CASE

A 27-year-old man was admitted with a three-day history of epigastric pain. Physical examination revealed tenderness and defense on palpation of epigastric region. There was a left subcostal incision with the history of diaphragmatic hernia repair when the patient was 3 days old. He had an intestinal malrotation with the cecum fixed at the epigastric region and the inflamed appendix extending beside the left lobe of liver.

DISCUSSION

While appendicitis is the most common abdominal disease requiring surgical intervention seen in the emergency room setting, intestinal malrotation is relatively uncommon. When patients with asymptomatic undiagnosed gastrointestinal malrotation clinically present with abdominal pain, accurate diagnosis and definitive therapy may be delayed, possibly increasing the risk of morbidity and mortality.

CONCLUSION

Atypical presentations of acute appendicitis should be kept in mind in patients with abdominal pain in emergency room especially in patients with previous childhood operation for diaphragmatic hernia.  相似文献   
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INTRODUCTION

Thrombocytopenia is a common problem occurring in patients and drug-induced thrombocytopenia is a significant cause of thrombocytopenia.

PRESENTATION OF CASE

We present an unusual case of thrombocytopenia that was considered to be associated with the use of hydroxychloroquine in the late term following open heart surgery.

DISCUSSION

The drug-induced thrombocytopenia, mechanical destruction of the platelets, and hemodilution are common causes of low platelet count. Although drug-induced immune thrombocytopenia has a mild clinical course in most cases (in this case it has severe clinical course), some patients may experience life-threatening hemorrhages. The decision to discontinue the drug that is deemed to be responsible from the drug-induced thrombocytopenia (DITP) relies on the clinical condition of the patient. The diagnosis is mostly established by discontinuation, exclusion, and correlation because the tests performed to detect drug-dependent antibodies (DDAbs) for the diagnosis of DITP are time-consuming, and these tests are also not commonly available. The authors of the current study diagnosed DITP by discontinuation of the drug. We suggest that the use of hydroxychloroquine could be severe thrombocytopenia occurring after open heart surgery.

CONCLUSION

The medication history must be carefully reviewed in patients presenting with thrombocytopenia, and if the medications could cause thrombocytopenia must be discontinued.  相似文献   
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