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11.
Peritoneal dialysis (PD) constitutes the preferred dialysis modality for children requiring renal replacement therapy with peritonitis being one of the most common complications of PD. This study was performed to evaluate the epidemiology, microbiology, and outcomes of PD-associated peritonitis in Greek children for a 10-year period. A total of 27 patients (16 males) with a mean age 121.8?±?57.2 months were retrospective analyzed. Patients were on PD therapy for a mean duration of 45.2?±?26.1 months. We found 23 episodes of PD-associated peritonitis occurred in 9 out of 27 patients (0.23 episodes/patient-year), with four patients experienced two or more peritonitis episodes. Gram-positive bacteria were responsible for 15 (65.2%) peritonitis episodes, with Staphylococcus aureus being the predominant specie isolated in 30.4% of cases. A total of seven episodes of exit-site infections (ESIs) were identified in five patients (0.069 episodes/patient-year) with the most common bacteria isolated being S. aureus (57.4%). Initial antibiotic treatment included intraperitoneal vancomycin plus ceftazidime in the majority of cases (82.6%). At the end of study, 12 (44.4%) patients remained on PD, 11 (41.8%) underwent renal transplantation, 2 (7.4%) shifted to hemodialysis and unfortunately, two patients (7.4%) died. Conclusively, our study revealed a noticeable low peritonitis and ESIs rate as compared to international data and represents the first evaluation of the characteristics and outcomes of peritonitis in the Greek pediatric PD population.  相似文献   
12.
Previous studies have shown that in vitro exposure to single compounds released from composite resins may induce cell death. In the present study the effects of eluates from commercially available composite resins used for direct or indirect restorations were evaluated on the cell cycle progression and type of cell death of cultured WEHI 13 var fibroblasts. Cells exposed to eluates of the materials were assessed for cytotoxicity by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay for cell death, for cell cycle profiles by flow cytometry, for caspase-3 biochemically and by immunocytochemistry, and for morphological changes by fluorescence microscopy with acridine orange. The direct composite resin eluates induced extensive apoptosis, followed by secondary necrosis. This was accompanied by cell enlargement, micromultinucleation, chromatin disintegration, cell cycle arrest at different phases, and caspase-3 activation. The composites for indirect restorations were much less cytotoxic at all biological end-points investigated. The findings suggest that composite resins used for direct and indirect dental restorations differ in their cytotoxic potential and their ability to affect basic cellular functions. This underlines the impact of improved polymerization with respect to their biologic behavior.  相似文献   
13.
Neurosurgical Review - Extracranial internal carotid artery dissection (ICAD) is a potential source of morbidity and mortality in trauma patients and requires high degree of suspicion for diagnosis...  相似文献   
14.
Osteoarthritis (OA) is a major cause of suffering for millions of people. Investigating the disease directly on humans may be challenging. The aim of the present study is to investigate the advantages and limitations of the animal models currently used in OA research. The animal models are divided into induced and spontaneous. Induced models are further subdivided into surgical and chemical models, according to the procedure used to induce OA. Surgical induction of OA is the most commonly used procedure, which alters the exerted strain on the joint and/or alter load bearing leading to instability of the joint and induction of OA. Chemical models are generated by intra-articular injection of modifying factors or by systemically administering noxious agents, such as quinolones. Spontaneous models include naturally occurring and genetic models. Naturally occurring OA is described in certain species, while genetic models are developed by gene manipulation. Overall, there is no single animal model that is ideal for studying degenerative OA. However, in the present review, an attempt is made to clarify the most appropriate use of each model.  相似文献   
15.
The mechanism of aortic pulse pressure decline induced by acute rapid ventricular pacing remains incompletely understood. It has been ascribed to changes in stroke volume or aortic compliance. This becomes more complicated by the dependence of aortic compliance on the level of the mean aortic pressure as well as the aortic wall properties. To test the role of such mechanical factors, aortic pressure-diameter hemodynamics, derived from simultaneous tip-micromanometer aortic pressure recordings and high-fidelity ultrasonic intravascular aortic diameter recordings, were measured in 15 normal subjects during and after abrupt cessation of rapid ventricular pacing (up to 160 bpm). Immediately after terminating the pacing, diastolic aortic pressure declined (–9%, from 87.4±1.2 to 79.5±1.7 mmHg,P<0.0001) while systolic aortic pressure increased (+19%, from 109.5±1.6 to 130.1±2.8 mmHg,P<0.0001). Thus, pulse pressure increased from 22.1±2.2 to 50.6±3.1 mmHg,P<0.0001. To quantify systolic and diastolic aortic pressure differences we compared the first postpaced beat (a) and the last paced beat (b). To estimate what the aortic pressure would have been for the paced beats had the aortic diameter differences due to the different heart rate not occurred we calculated the theoretical pressure of the paced beat Pb=Eb·Da, where Eb was the instantaneous aortic elastance of the paced beat and Da was the aortic diameter for the postpaced beat. The corrected pressure difference was then calculated by the following: Pcor=(Da·Eb)–Pa. It was found that systolic Pcor was 25% of systolic Praw and diastolic Pcor was 89% of diastolic Praw. Praw was the pressure difference between paced and spontaneous beat measured from the raw data. Pcor indicates the portion of Praw that results from a change in aortic stiffness as a consequence of viscous behavior or aorto-ventricular coupling. These data indicate that the majority of diastolic pressure decline after pacing was terminated, may reflect a change in aortic stiffness while the majority of systolic pressure rise, and may be attributable to differences in hemodynamics alone.  相似文献   
16.

Background

Angiosarcomas are rare tumors that carry poor prognosis. Because of insidious growth rate, the diagnosis is often difficult and delayed.

Methods

Between 1990 and 2011, 72 (41 female, 31 male) patients were treated at our institution. Pathologic confirmation was obtained and multiple prognostic factors were evaluated for survival.

Results

Forty-four cases were sporadic and 28 cases were secondary. In the sporadic group, 16 (36%) patients had increased sun exposure, while in the secondary group, the majority (n = 23, 82%) of patients had prior exposure to radiation. The latent period between radiation exposure and diagnosis was predictive of survival (P = .037). Presentation was delayed by more than 3 months in 41% of patients. The majority of men developed head and neck angiosarcomas (n = 15, 48.5%), while women developed breast angiosarcomas (n = 21, 51%). Median survival was prolonged in patients treated initially with surgery.

Conclusions

A delay in the diagnosis of angiosarcoma can affect survival. Clinical suspicion and prompt diagnosis are essential for successful multimodal therapy. Initial surgical resection with adjuvant chemotherapy provides survival advantage.  相似文献   
17.
Acute or subacute thrombosis and late restenosis remain the main limitations of permanent stenting. In an effort to address these limitations, an autologous vein graft-coated stent (AVGCS) was developed at our institution. This stent consists of a conventional stent (Palmaz or Palmaz-Schatz, Johnson and Johnson), which is covered by an autologous vein graft. After successful experimental implantation, we report here the immediate results of the percutaneous implantation of AVGCS in 7 patients with coronary artery disease (6 de novo lesions and 1 bailout case). The results of this preliminary study indicate that the preparation of the AVGCS is easy and feasible. The Implantation of the AVGCS was uncomplicated, and the immediate angiographic results were excellent. This new type of coated stent may be useful in addressing current limitations of balloon angioplasty. © 1996 Wiley-Liss, Inc.  相似文献   
18.
Thromboprophylaxis, as a preventive measure for cancer-associated thrombosis (CAT), may be beneficial for patients with active cancer and high-risk for thrombosis. The present post hoc analysis include a total of 407 patients enrolled in the Greek Management of Thrombosis study, who received thromboprophylaxis with tinzaparin. The objectives of the present analysis were: i) To obtain sufficient evidence for the administration of prophylaxis in patients with active cancer, irrespective of Khorana risk assessment model score; ii) to identify the selection criteria for both dose and duration of tinzaparin; and iii) to evaluate the efficacy and safety of tinzaparin administered for CAT prophylaxis. The main tumor types for the patients included in the present study were as follows: Lung (25.1%), pancreatic (14.3%), breast (9.1%), stomach (8.4%), colorectal (7.9%) and ovarian (7.6%). Furthermore, metastatic disease was observed in 69.5% of the patients. High thrombotic burden agents (HTBAs) were administered to 66.3% of the patients, and 17.4% received erythropoietin. A total of 43.7% of the patients exhibited a Khorana score <2. The results of the present study demonstrated that both the presence of metastatic disease and the use of HTBAs seemed to influence oncologists'' decisions for the use of thromboprophylaxis in patients with active cancer, regardless of Khorana score. Tinzaparin, in dose expressed in the standard notation for heparins, i.e., anti-Xa factor international units (Anti-Xa IU), was administered at an intermediate dose (InterD; 8,000-12,000 Anti-Xa IU; once daily) to 52.4% of patients, while the remaining patients received a prophylactic dose (ProD; ≤4,500 Anti-Xa IU; once daily). The average duration of thromoprophylaxis was 5 months. Furthermore, a total of 14 (3.4%) thrombotic events and 6 (1.5%) minor bleeding events were recorded. A total of four thrombotic events were observed following an InterD treatment of tinzaparin, while 10 thrombotic events were observed following ProD treatment. The present study also demonstrated that an InterD of tinzaparin was administered more frequently to patients with a body mass index >30 kg/m2, a history of smoking and a history of metastatic disease, along with administration of erythropoietin. InterD tinzaparin treatment was found to be potentially more efficacious and without safety concerns. The present study is a registered clinical trial (ClinicalTrials.gov code, NCT03292107; registration date, September 25, 2017).  相似文献   
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