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PURPOSE: To investigate dosimetric predictors of laryngeal edema after radiotherapy (RT). METHODS AND MATERIALS: A total of 66 patients were selected who had squamous cell carcinoma of the head and neck with grossly uninvolved larynx at the time of RT, no prior major surgical operation except for neck dissection and tonsillectomy, treatment planning data available for analysis, and at least one fiberoptic examination of the larynx within 2 years from RT performed by a single observer. Both the biologically equivalent mean dose at 2 Gy per fraction and the cumulative biologic dose-volume histogram of the larynx were extracted for each patient. Laryngeal edema was prospectively scored after treatment. Time to endpoint, moderate or worse laryngeal edema (Radiation Therapy Oncology Group Grade 2+), was calculated with log rank test from the date of treatment end. RESULTS: At a median follow-up of 17.1 months (range, 0.4- 50.0 months), the risk of Grade 2+ edema was 58.9% +/- 7%. Mean dose to the larynx, V30, V40, V50, V60, and V70 were significantly correlated with Grade 2+ edema at univariate analysis. At multivariate analysis, mean laryngeal dose (continuum, hazard ratio, 1.11; 95% confidence interval, 1.06-1.15; p < 0.001), and positive neck stage at RT (N0-x vs. N +, hazard ratio, 3.66; 95% confidence interval, 1.40-9.58; p = 0.008) were the only independent predictors. Further stratification showed that, to minimize the risk of Grade 2+ edema, the mean dose to the larynx has to be kept < or =43.5 Gy at 2 Gy per fraction. CONCLUSION: Laryngeal edema is strictly correlated with various dosimetric parameters; mean dose to the larynx should be kept < or =43.5 Gy.  相似文献   
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IntroductionRevision penile prosthesis surgery has traditionally been associated with a greater risk of postoperative infection than primary implant placement. This has been attributed to the high prevalence of asymptomatic bacteria found surrounding the implant at the time of revision surgery.AimTo validate whether contemporary revision surgery remains associated with a high risk of asymptomatic colonization and postoperative infection.MethodsA comprehensive, prospective database consisting of consecutive patients undergoing primary and revision penile prosthesis surgery at our center was analyzed.Main Outcome MeasuresThe infection risk in primary and revision implant surgery was compared. The prevalence of asymptomatic implant colonization during revision surgery, and whether this was associated with clinical infection was evaluated. The spectrum of bacterial species causing infection in this contemporary single-surgeon series was described.ResultsOne hundred seventeen primary and 72 revision implant recipients were studied. Infection developed in four (3.4%) patients undergoing primary implants, two (4.3%) patients undergoing removal and replacement for mechanical malfunction, and three (12%) patients undergoing rerouting for extrusion (P = 0.26). Intraoperative cultures were positive in 5 (9.8%) of 51 revision patients, none of whom developed infections. Organisms causing infection included Staphylococcus aureus and Enterobacter aerogenes. Unexpectedly, an adjuvant, alcohol-based skin prep in our last 83 patients reduced the infection risk to 1.2%.ConclusionsIn our series, the infection risk associated with revision of malfunctioning devices was no greater than primary implant placement. Rerouting was associated with a higher infection risk, likely due to technical factors, and not implant colonization. Less than 10% of our revision implants were colonized, and this had no bearing on the development of a postoperative infection. S. epidermidis was not the most common organism implicated in device infections. Finally, our experience with an adjuvant, alcohol-based skin prep warrants further randomized prospective evaluation. Kava BR, Kanagarajah P, and Ayyathurai R. Contemporary revision penile prosthesis surgery is not associated with a high risk of implant colonization or infection: A single-surgeon series.  相似文献   
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In this study, a series of new 1,2,4-oxadiazole derivatives containing 3,4-dihydro-2H-chromen-2-amine moiety were synthesized by efficient microwave reaction of 2-amino-N′-hydroxychroman-3-carboxamidine and suitable aldehyde. Structures of all the synthesized compounds were confirmed by spectral studies and C, H, N analyses. Newly synthesized compounds were screened for their anticonvulsant and anti-inflammatory properties. Few of the compounds exhibited excellent anticonvulsant activity as compared to the standard drug Diazepam. Also compounds have exhibited moderate anti-inflammatory activity as compared to the standard drug Diclofenac sodium.  相似文献   
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Lichenoid reaction represents a family of oral lesions identical, both clinically and histologically to oral lichen planus. The triggering factor for this lesion varies from medicines to dental materials, usually demonstrating a cause-effect relationship unlike lichen planus. We present a typical case of lichenoid reaction on the buccal mucosa that appeared in response to betel quid which progressed to carcinoma during a follow-up period of 6 months. Lichenoid reactions occurring in response to known carcinogens and that occurring in risk group population has to be observed more cautiously.  相似文献   
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Thermal stability, structure and mechanical properties of the multi-component Zr58.5Ti8.2Cu14.2Ni11.4Al7.7 bulk metallic glass have been studied in detail. The glassy material displays good thermal stability against crystallization and a fairly large supercooled liquid region of 52 K. During heating, the alloy transforms into a metastable icosahedral quasicrystalline phase in the first stage of crystallization. At high temperatures, the quasicrystalline phase undergoes a transformation to form tetragonal and cubic NiZr2-type phases. Room-temperature compression tests of the as-cast sample show good mechanical properties, namely, high compressive strength of about 1,630 MPa and fracture strain of 3.3%. This is combined with a density of 6.32 g/cm3 and values of Poisson’s ratio and Young’s modulus of 0.377 and 77 GPa, respectively. The mechanical properties of the glass can be further improved by cold rolling. The compressive strength rises to 1,780 MPa and the fracture strain increases to 8.3% for the material cold-rolled to a diameter reduction of 10%.  相似文献   
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ObjectivesThis study sought to assess the presence and extent of focal and diffuse fibrosis in heart failure in patients with preserved ejection fraction (HFpEF) compared to asymptomatic control subjects, and the relationship of fibrosis to clinical outcome.BackgroundMyocardial fibrosis has been implicated in the pathophysiology of HFpEF.MethodsIn this prospective, observational study, 140 subjects of similar age and sex (HFpEF: n = 96; control subjects: n = 44; 73 ± 8 years of age; 49% males) underwent cardiac magnetic resonance imaging. Late gadolinium-enhanced (LGE) imaging and T1 mapping to calculate myocardial extracellular volume indexed to body surface area (iECV) were used to assess fibrosis.ResultsPatients with HFpEF had more concentric remodeling and worse diastolic function. Focal fibrosis was more frequent in HFpEF subjects (overall: n = 49; infarction: n = 17; nonischemic cases: n = 36; mixed patterns: n = 4) than in control subjects (overall: n = 3). Diffuse fibrosis was also greater in HFpEF subjects than control subjects (iECV: 13.7 ± 4.4 ml/m2 versus 10.9 ± 2.8 ml/m2; p < 0.0001). During median follow-up (1,429 days), there were 42 composite events (14 deaths; 28 heart failure hospitalizations) in cases of HFpEF. Myocardial infarction revealed on LGE imaging was a predictor of outcomes on univariate analysis only. With multivariate analysis, iECV (hazard ratio [HR]: 1.689; 95% confidence interval [CI]: 1.141 to 2.501; p = 0.009) was an independent predictor of outcome along with mitral peak velocity of early filling (E)-to-early diastolic mitral annular velocity (E′) (E/E′) ratio (HR: 1.716; 95% CI: 1.191 to 2.472; p = 0.004) and prior HF hospitalization (HR: 2.537; 95% CI: 1.090 to 5.902; p = 0.031). iECV was also significantly associated with ventricular/left atrial remodeling and renal dysfunction: right ventricular end-diastolic volume indexed (r = 0.456; p < 0.0001), left ventricular mass/volume (r = 0.348; p = 0.001), maximal left atrial volume indexed (r = 0. 269; p = 0.009), and creatinine (r = 0.271; p = 0.009).ConclusionsBoth focal and diffuse myocardial fibrosis are more prevalent in HFpEF subjects than in control subjects of similar age and sex. iECV significantly correlates with indices of ventricular/left atrial remodeling and renal dysfunction and is an independent predictor of adverse outcome in HFpEF. (Developing Imaging And plasMa biOmarkers iN Describing Heart Failure With Preserved Ejection Fraction [DIAMONDHFpEF]; NCT03050593)  相似文献   
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