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Meckel's diverticulum (MD) is a persistent embryonic remnant occurring in 2% of the general population. This entity is usually clinically silent and is only discovered when complications occur. Diagnosis is rarely made preoperatively. Surgical resection of symptomatic MD is widely accepted but the most appropriate management of asymptomatic MD remains unclear. We present a case of MD that summarizes some of the complications that may occur. The peculiarity of this case was that the complications were caused by a leiomyoma. The presence of tumoral disease in MD accounts for 3.2% of complications. The most common neoplasm is carcinoid tumor. Few publications have reported benign neoplasms in MD, probably due to their low incidence.  相似文献   
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Liver macronodules, ranging from benign to low-grade or high-grade dysplastic nodules (LGDNs/HGDNs) and hepatocellular carcinoma (HCC), may develop during chronic liver diseases (CLDs). Current guidelines were recently updated and the noninvasive criteria for the diagnosis of small HCC are based on a single typical radiological pattern and nonconclusive coincidental findings with two techniques. This study aimed to assess the accuracy and disagreements of noninvasive multiphasic examinations for the diagnosis of HCC and dysplastic nodules (DNs) and the role of biopsy. Seventy-four consecutive patients with CLD with ultrasound-detected 1-2-cm nodules underwent, within 1 month, multiphasic computed tomography (CT), magnetic resonance imaging (MRI), and biopsy of the nodule. Median age was 60 years; 33 patients (45%) had hepatitis C virus, 20 (27%) had hepatitis B virus, and 13 (18%) patients had no cirrhosis. Biopsy revealed 47 HCCs, 6 HGDNs, 1 LGDNs, 1 cholangiocarcinoma, and 1 epithelioid hemangioendothelioma. There were no tumors in the other 18 patients. All patients (31 of 31; 100%) who had conclusive coincidental findings (i.e., arterial enhancement and washout) on both examinations had HCC or HGDN (sensitivity, 57%; specificity, 100%). All patients (51 of 51; 100%) who had conclusive findings on at least one of the two examinations had HCC or HGDN (sensitivity, 96%; specificity, 100%). There was a disagreement regarding imaging findings between CT and MRI in 21 of 74 (28%) patients and no washout on both examinations in 23 of 74 patients (31%). In these 44 patients, liver biopsy provided an initial accurate diagnosis. CONCLUSION: The noninvasive diagnosis of HCC or HGDN can be obtained if arterial enhancement and washout are found in a single dynamic imaging examination. These findings are frequently discordant on both CT and MRI, supporting the place of biopsy for the diagnosis of small HCCs.  相似文献   
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Little is known about the vascular function and expression of endothelial and neuronal nitric oxide synthases (eNOS and nNOS) in Duchenne muscular dystrophy (DMD). Bradykinin is involved in the regulation of eNOS expression induced by angiotensin-converting enzyme inhibitors. We characterized the vascular function and eNOS and nNOS expression in a canine model of DMD and evaluated the effects of chronic bradykinin treatment. Vascular function was examined in conscious golden retriever muscular dystrophy (GRMD) dogs with left ventricular dysfunction (measured by echocardiography) and in isolated coronary arteries. eNOS and nNOS proteins in carotid arteries were measured by western blot and cyclic guanosine monophosphate (cGMP) content was analyzed by radioimmunoassay. Compared with controls, GRMD dogs had an impaired vasodilator response to acetylcholine. In isolated coronary artery, acetylcholine-elicited relaxation was nearly absent in placebo-treated GRMD dogs. This was explained by reduced nNOS and eNOS proteins and cGMP content in arterial tissues. Chronic bradykinin infusion (1 μg/min, 4 weeks) restored in vivo and in vitro vascular response to acetylcholine to the level of control dogs. This effect was NO-mediated through upregulation of eNOS and nNOS expression. In conclusion, this study is the first to demonstrate that DMD is associated with NO-mediated vascular endothelial dysfunction linked to an altered expression of eNOS and nNOS, which can be overcome by bradykinin.  相似文献   
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Previous findings from researchers on individuals with Asperger Syndrome (AS) suggest peculiarities of autobiographical memory (AM). They have shown a personal episodic memory deficit in the absence of a personal semantic memory impairment. The primary aim of this study was to explore AM in individuals with AS, and more specifically to investigate the link between episodic memory, self-awareness, and autonoetic consciousness through language analysis. We asked fifteen adults with AS and fifteen age- and IQ-matched controls to recall autobiographical memories from three life periods. Recorded interviews were processed using Alceste software. We found that participants with AS recalled fewer and less-detailed episodic memories than did controls. A content analysis revealed that family-related vocabulary as well as possessive pronouns was significantly less frequent in AS interviews than in those of controls. In conclusion, our results support the hypothesis that a deficiency of episodic memory may be due to poor awareness of the self in social relationships. Reduced use of possessive pronouns may also indicate less self-investment in life experiences, which would in turn impact recall.  相似文献   
107.
Purpose: The aim of this study was to evaluate the early bone response of tapered and cylindrical root form implants with two different surface treatments in fresh extraction sockets after 4 and 8 weeks. Materials and Methods: Surface treatments and implant design comprised (n = 9 each): tapered with dual acid‐etched surface; tapered with dual acid‐etched and sandblasted surface (T DAE SB); cylindrical with dual acid‐etched surface (C DAE); and cylindrical with dual acid‐etched and sandblasted surface (C DAE SB). Implants were placed in the distal sockets of mandibular premolars (2P2,3P3,4P4) of six beagle dogs, remaining in vivo for 4 and 8 weeks. After sacrifice, the implants were subjected to torque to the point of interface fracture and subsequently nondecalcified for histomorphological study. Statistical analysis was performed by a General Linear Model (GLM) analysis of variance model with a significance level of 5%. Results: Torque to interface fracture was significantly greater for the C DAE SB group than for the other groups (p < .001). Histomorphological analysis showed woven bone formation around all implant surfaces at 4 weeks and its replacement by lamellar bone at 8 weeks. Study time (4 or 8 weeks) did not affect torque measures. Conclusions: The double acid‐etched and sandblasted sample surface increased early bone biomechanical fixation of both cylindrical and tapered root form implants. The cylindrical root form implants showed higher torque to interface fracture values when compared with the tapered root form implants. The C DAE SB surface group showed the highest biomechanical fixation values (p < .001).  相似文献   
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