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Pacing lead dislodgement contributes substantially, to the list of causes of early pacemaker failure.Reel''s syndrome is a rare cause of pacemaker failure, resulting from the dislodging of pacing electrodes by manipulation of the pulse generator by the patient. We describe here an intriguing case of pacemaker lead dislodgement by a novel and frequently underdiagnosed mechanism that mimicked the fluoroscopic diagnosis of reel''s syndrome.  相似文献   
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The most frequent type of treatment for patients diagnosed with a malignant neoplasia of the oral cavity is surgical resection of the tumor. Ablative surgery may be followed by a reconstructive phase, in which the surgeon may choose between local flaps, nonvascularized bone grafts or free vascularized flaps to close the surgical site, depending on the general conditions of the patient. Esthetic and functional results are challenging to achieve for the prosthodontist, as variable amount of hard and soft tissues are removed. This report describes the fabrication of a two‐piece hollow obturator for a 19‐year‐old patient who underwent wide surgical excision of the osteosarcoma of the maxilla and was rehabilitated to function. In this case, the surgical site was covered with submental flap, and the second piece of the obturator provided fullness to the lost malar prominence.  相似文献   
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Fractures of metal-ceramic restoration pose an esthetic and functional dilemma both for patient and the dentist. Intraoral repair systems eliminate the remake and removal of restoration. Many intraoral repair materials and surface treatments are available to repair intraorally fractured metal-ceramic restoration. Bond strength data of various materials and specific technique used for repair are necessary for predicting the success of a given repair system. This study evaluated the shear bond strength of three different intraoral repair systems for metal-ceramic restorations applied on exposed metal and porcelain surface. One hundred and twenty metal discs (20 mm in diameter × 0.7 mm thick) were fabricated with nickel–chromium alloy (Mealloy, Dentsply, USA). Feldspathic porcelain (Duceram, Degudent, Germany) were applied over one test surface of the discs in the thickness of 1.8 mm followed by conventional firing. The defect, which simulates clinical failures were created in 1/4th area of the metal-ceramic discs. The metal-ceramic discs samples were divided into ceramic substrate (Group I, n = 60) and metal substrate (Group II, n = 60), according to the defect location. Then, samples of ceramic substrate (Group I) and metal substrate (Group II) were subdivided into A, B according to the surface treatments (A; roughening with diamond bur and B; abraded with 50 μ Al2O3) and repaired with one of the intraoral repair systems tested (a. Ceramic repair system, Ivoclar Vivadent; b. Clearfil repair system, Kurary, c; Porcelain repair system, 3 M ESPE). All the repaired samples were stored in distilled water at 37 °C for 24 h. After thermocycling at 6–60° C, all the samples were stored at 37 °C for additional 7 days. Shear bond strength of all the samples were calculated by using Universal testing machine. The mean shear bond strength values for the group I (A/B) were as follows: Ceramic repair system (9.47 ± 1.41/14.03 ± 2.54 MPa), Clearfil repair system (14.03 ± 2.32/14.64 ± 2.28 MPa), and Porcelain repair system (14.41 ± 3.96/14.86 ± 3.10 MPa). The mean shear bond strength values for the group II (A/B) were as follows: Ceramic repair system (9.42 ± 1.44/18.61 ± 2.60 MPa), Clearfil repair system (14.44 ± 3.23/14.98 ± 2.73 MPa), and Porcelain repair system (11.86 ± 2.24/13.24 ± 2.72 MPa). Air abrasion with 50 μm aluminum oxide particles is the preferred surface treatment. Porcelain repair system showed the highest shear bond with air abrasion for ceramic substrate and for metal substrate Ceramic repair system showed the highest bond strength with air abrasion as a surface treatment. This study suggest that the three repair systems tested are adequate for intraoral chairside repair of metal-ceramic restoration when air abrasion is used for surface treatment of the substrate (Ceramic repair system, Ivoclar Vivadent, Germany; Clearfil repair system, Kurary, Japan; Porcelain repair system, 3M ESPE, Germany).  相似文献   
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Despite proof of voluntary counseling and testing (VCT) effectiveness in HIV disease prevention and management, there are limited reports on experience with pre- and post-HIV-test counseling in developing countries. In view of this, we aimed to bring to the fore the voluntary counseling and testing experience at a tertiary healthcare center. The present study was conducted at the voluntary counseling and testing center of a tertiary healthcare center and the National HIV Reference Center. Participants were 1169 men and 581 females attending the VCT clinic from February 2005 to March 2006. Odds ratios were calculated for each of the variable to analyze the strength of association with HIV sero-status. Out of 1750 patients, 322 (27.5%) males and 156 females (26.9%) tested HIV-positive. HIV-sero-positivity was observed to be associated to participant age (approximately 1.5 for 25-44 yrs age group), marital status (2.3 times in married patients), primary or lower education level (1.5 times), citing spouse death/HIV-infected spouse as the reason for seeking VCT (2.2 times) and reporting a history of risk behavior as reason for getting tested. This study aims to evaluate the effectiveness of existing client initiated voluntary counseling and testing facility in the light of a recent recommendation by WHO/UNAIDS for the implementation of provider initiated voluntary counseling services. Through this study, we could also highlight socio-demographic factors, like education and age, and reasons stated by participants for seeking VCT, which were associated with HIV-positive status and put an individual at a higher risk of HIV infection.  相似文献   
27.
Agrawal A  Agrawal KP  Ram A  Sondhi A  Chhabra SK  Gangal SV  Mehta D 《Lung》2005,183(6):375-387
The aim of this study was to investigate the basis of disturbances in sodium transport in asthma and in airway hyperresponsiveness without symptoms of asthma (asymptomatic AHR). We measured the intracellular sodium (Nai); activity of Na+/K+-ATPase in unstimulated cells (resting activity) and in cell homogenate under optimal conditions (maximal activity); and sodium influx, in mixed leukocytes of 15 normal subjects, 12 subjects with asymptomatic AHR, and 26 asthmatics with or without active symptoms. Resting Na+/K+-ATPase activity was the same as sodium influx, consistent with homeostasis. Compared with normal subjects, those with asymptomatic AHR or asthma with controlled symptoms had a twofold increase in sodium influx and Nai. Symptomatic asthmatics also had a twofold increase in sodium influx but a fourfold elevation of Nai. Maximal Na+/K+-ATPase activity was reduced by half in symptomatic asthmatics compared with normal subjects. The reduction of maximal Na+/K+-ATPase activity was associated with a significant decrease in ATP turnover per Na+/K+-ATPase molecule but not number of Na+/K+-ATPase molecules per cell. In summary, airway hyperresponsiveness with or without asthma is associated with increased sodium influx and Na in leukocytes. Resting activity of Na+/K+-ATPase is also increased as a compensatory response to the increased sodium influx, but it is achieved at the expense of higher Nai. Symptomatic asthma is additionally associated with reduction in maximal activity of Na+/K+-ATPase, resulting in reduced capacity to handle the increase in sodium influx and consequent severe elevations in Nai.  相似文献   
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Ciliated hepatic foregut cyst is a rare foregut cystic developmental malformation. It presents as a solitary cystic lesion in segment four of the liver. Histologically, it consists of four distinct layers; namely, the inner ciliate columnar epithelium, subepithelial connective tissue, smooth muscle layer, and an outer fibrous layer. Usually asymptomatic and detected incidentally, other modes of presentation can include portal hypertension, obstructive jaundice, and development of malignancy. We present a case of a young asymptomatic woman with a complex cyst in segment four of the liver, who underwent a laparoscopic resection, focusing our discussion on the review of the literature and the diagnostic dilemma encountered in these rare cases.  相似文献   
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