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31.
AE Calogero F Nicoletti MA Palumbo N Burrello M Di Mauro M Lunetta K Bendtzen A Cianci 《Canadian Metallurgical Quarterly》1998,10(10):814-818
Myoclonus of the middle ear is a rare condition characterized by abnormal repetitive muscle contractions of the tympanic cavity. In this paper we describe what we believe is the first reported case of continuous high-frequency objective tinnitus caused by middle ear myoclonus. During exploratory tympanomastoidectomy it was hypothesized that a small dural arteriovenous malformation not identified on previous tests was the cause of the tinnitus. However, complete disappearance of the tinnitus during administration of curare for anesthesia led us to believe that the tinnitus might have been caused by myoclonus of the middle ear. Sectioning of the stapedius and tensor tympani tendons rendered the patient asymptomatic and confirmed the diagnosis of middle ear myoclonus. At follow-up of one year, the patient's quality of life had improved substantially; the tinnitus did not recur and she no longer had vertigo. 相似文献
32.
Lennard F. Torres Zach McCaffrey Wisdom Washington Tina G. Williams Delilah F. Wood William J. Orts Colleen M. McMahan 《应用聚合物科学杂志》2021,138(28):50684
This study explored the feasibility of using torrefied biomass as a reinforcing filler in natural rubber compounds. Carbon black was then replaced with the torrefied biomass in elastomer formulations for concentrations varying from 0% to 100% (60 parts per hundred rubber or phr total). Their influence on the curing process, dynamic properties, and mechanical properties was investigated. Results were compared with the properties of vulcanizates containing solely carbon black fillers. Time to cure (t90) for compounds with torrefied biomass fillers increased, while filler-filler interactions (ΔG') decreased, compared to carbon black controls. At low strains, the tan δ values of the torrefied fillers vulcanizates were similar to the controls. Incorporation of torrefied biomass into natural rubber decreased compound tensile strength and modulus but increased elongation. Replacement with torrefied fillers resulted in a weaker filler network in the matrix. Still, results showed that moderate substitution concentrations (~20 phr) could be feasible for some natural rubber applications. 相似文献
33.
Reports of bile duct injuries are from tertiary care institutions and, therefore, may not report the spectrum of management that these patients receive in the care of these injuries. From June 14,1990 (the first operation) to June 30, 1995, 2654 laparoscopic cholecystectomies (LCs) were reviewed at this community hospital medical center to determine risk factors contributing to the etiology of these injuries, time and symptoms at presentation, duration of illness, and management of these injuries. None of the 13 general surgeons practicing during this time period had laparoscopic training in a general surgical residency. There were six major bile duct injuries (0.25%), of which five were available for further review. All occurred in women with cholelithiasis and chronic cholecystitis. Two operations were routine and two were associated with biliary tract anomalies. In two patients, the injuries were detected at LCs and definitive biliary-enteric anastomoses were performed immediately. Three patients presented at 2, 15, and 42 days after LC. In two patients, one or more operative procedures were performed before definitive repair and these patients were referred to tertiary care centers. One patient was managed with sequential CT-guided drainage catheters after attempted closure of the defect. The length of illness for these five patients was 8, 69, 348, 402, and 435 days with a follow-up of 245, 345, 531, 575, and 1088 days. Laparoscopic experience before injury by the operating surgeon was 3, 26, 35, 77, and 333 operations. Major biliary tract injuries occurred during routine cholecystectomy, length of illness was substantial for most patients, and biliary-enteric anastomosis was definitive for four of the five patients. The operating surgeons' "learning curve" did not seem as important as in other studies. 相似文献
34.
EO Johnson MB van den Bree AE Gupman RW Pickens 《Canadian Metallurgical Quarterly》1998,22(7):1421-1429
Mild, severe, and dyssocial subtypes of alcohol dependence, previously identified among Caucasian men from the Epidemiologic Catchment Area study, were also identified among Caucasian men and women with DSM-IV alcohol dependence from the National Longitudinal Alcohol Epidemiologic Survey (n = 2,703; 1,746 respectively). These subtypes were not identified among African American and Hispanic American men or women with DSM-IV alcohol dependence. Among Caucasians with alcohol dependence, the subtypes were characterized by differential loading on three dimensions: genetic, general environmental, and dyssocial environmental symptom scales developed in a prior twin study. The mild subtype (60% of men and 66% of women) was distinguished by low mean scores on all three scales; the dyssocial subtype (24% of men and 20% of women) by low mean genetic and general environmental scores but high mean dyssocial environmental scores; and the severe subtype (16% of men and 14% of women) by high scores on the genetic and general environmental scales. These subtypes also showed the expected distinctions in clinical characteristics. The severe subtype showed greater comorbid drug dependence and major depression, more treatment seeking, and a higher prevalence of parental alcoholism. The severe subtype also showed significantly greater genetic influence adjusted for overall severity of alcohol dependence (genetic ratio). Only the severe subtype showed a pattern of scale scores and clinical characteristics suggestive of substantial genetic influence. The present study indicates a robustness of the typology originally developed among DSM-III alcohol-dependent Caucasian men by empirical extension of the subtypes to a different sample of Caucasian men and, separately, Caucasian women. The use of this typology may aid in distinguishing between Caucasian alcohol-dependent individuals on the basis of relative genetic influence, enabling genetic, behavioral, and epidemiological investigations to reduce genetic or environmental "noise" and better focus on specific aspects of alcohol dependence. 相似文献
35.
AD Gouliamos DS Kontogiannis J Androulidakis AE Kalovidouris LJ Vlahos CG Papavasiliou 《Canadian Metallurgical Quarterly》1993,17(3):446-448
The MR studies of three histologically proven spinal neurilemmomas and neurofibromas were reviewed retrospectively. There were two benign neurilemmomas (schwannomas) and one neurofibroma. The common characteristic of these cases was a central low intensity focus ("dot") seen on postcontrast T1-weighted imaging. The low intensity foci corresponded histologically to a congeries of changes including edema, microcysts, foam cells, hyalinization of blood vessels, old hemorrhage, and dystrophic calcification. 相似文献
36.
Mean MMPI profiles of 40 Indian and 40 White veterans were similar, but "Indianism," as measured by the Indian Culturalization Test, was significantly related to scores on Hs, Hy, Pt and Sc scales. Caution is advised in using the MMPI in the diagnosis of Indians' psychiatric problems. 相似文献
37.
Paula C. Rodrigues Bruno D. Fontes Bruno B. M. Torres Washington S. Sousa Gregório C. Faria Debora T. Balogh Roberto M. Faria Leni Akcelrud 《应用聚合物科学杂志》2015,132(38)
Synthesis of a polyfluorene/poly(p‐phenylene vinylene) derivative, the Poly [(9,9′‐di‐hexylfluorenediylvinylene‐alt‐1,4‐phenylenevinylene)‐co‐((9,9′‐(3‐t‐butylpropanoate) fluorene‐1,4‐phenylene)] (LaPPS 42) was performed following Wittig and Suzuki routes. Polyfluorenes and derivatives have been used in electroluminescent devices, and the synthesis described here has the advantage in pave the way to get distinct structures having different emission spectra. An extensive study of its electrochemical, thermomechanical, optical, and structural properties was carried out, as well as its application in electroluminescent devices. Polymer light‐emitting diodes (PLEDs) and polymer light‐emitting electrochemical cells (PLECs) were built using LaPPS 42 as active layer, and their electric and optical characterizations confirm they have a potential as active element in electroluminescent devices. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42579. 相似文献
38.
Myers MJ Yancy HF Farrell DE Washington JD Frobish RA 《Journal of food protection》2005,68(12):2656-2664
Performance characteristics were evaluated for two lateral-flow test kits, Reveal for Ruminant in Feed (Neogen Corporation) and FeedChek (Strategic Diagnostics Inc.), designed to detect ruminant or terrestrial animal proteins in feeds. The stringent acceptance criteria used were developed by the Center for Veterinary Medicine Office of Research to identify test kits with comparable selectivity and sensitivity to microscopy and PCR assay, the analytical methods used by the U.S. Food and Drug Administration (FDA). Guidelines were developed for evaluating the selectivity, sensitivity, ruggedness, and specificity of these kits. These guidelines further stated that ruggedness and specificity testing would be performed only after a test passed both the selectivity and sensitivity assessments. Acceptance criteria for determining success were developed using a statistical approach requiring 90% probability of achieving the correct response, within a 95% confidence interval. A minimum detection level of 0.1% bovine meat and bone meal, consistent with the sensitivity of the methods used by the FDA, was required. Selectivity was assessed by testing 60 dairy feed samples that contained no added animal proteins; sensitivity was determined by evaluating 60 samples (per level of fortification) of the same feed that contained 0.025, 0.05, 0.1, 0.25, 0.5, 1, or 2% bovine meat and bone meal. The Reveal test passed the selectivity assessment but failed the sensitivity assessment, detecting only samples fortified at the 2% level and then only 17 to 33% of those samples, when read according to the label directions. The FeedChek test passed the sensitivity assessment but failed the selectivity assessment, with rates for false-positive results ranging from 34 to 38%, depending on the user. The sensitivity of the Reveal test was affected by the concentration of trace minerals present in the feed; concentrations toward the high end of the normal range prevented the detection of true positive feed samples containing bovine meat and bone meal. Better sensitivity assessments were obtained when lamb meal was used either alone or in combination with bovine meat and bone meal. The FeedChek test was not affected by the concentration of trace minerals or by the type of animal meal used. These results indicate that neither of the two tests is adequate for routine regulatory use. 相似文献
39.
In the investigation of ischemic stroke, conventional structural magnetic resonance (MR) techniques (e.g., T1-weighted imaging, T2-weighted imaging, and proton density-weighted imaging) are valuable for the assessment of infarct extent and location beyond the first 12 to 24 hours after onset, and can be combined with MR angiography to noninvasively assess the intracranial and extracranial vasculature. However, during the critical first 6 to 12 hours, the probable period of greatest therapeutic opportunity, these methods do not adequately assess the extent and severity of ischemia. Recent developments in functional MR imaging are showing great promise for the detection of developing focal cerebral ischemic lesions within the first hours. These include (1) diffusion-weighted imaging, which provides physiologic information about the self-diffusion of water, thereby detecting one of the first elements in the pathophysiologic cascade leading to ischemic injury; and (2) perfusion imaging. The detection of acute intraparenchymal hemorrhagic stroke by susceptibility weighted MR has also been reported. In combination with MR angiography, these methods may allow the detection of the site, extent, mechanism, and tissue viability of acute stroke lesions in one imaging study. Imaging of cerebral metabolites with MR spectroscopy along with diffusion-weighted imaging and perfusion imaging may also provide new insights into ischemic stroke pathophysiology. In light of these advances in structural and functional MR, their potential uses in the study of the cerebral ischemic pathophysiology and in clinical practice are described, along with their advantages and limitations. 相似文献
40.
AE Fiore C Iverson T Messmer D Erdman SM Lett DF Talkington LJ Anderson B Fields GM Carlone RF Breiman MS Cetron 《Canadian Metallurgical Quarterly》1998,46(9):1112-1117
OBJECTIVES: To determine the causes of an outbreak of lobar pneumonia. DESIGN: Matched (1:2) case-control study. SETTING: A 70-bed chronic care facility for older people. PARTICIPANTS: Residents of the facility. RESULTS: Ten residents developed pneumonia over a 10-day period. Two residents died. One case-patient had Streptococcus pneumoniae bacteremia; another had polymerase chain reaction evidence of S. pneumoniae infection. No other etiologic agent was identified. Only four of 10 case-patients had received routine diagnostic cultures of blood or sputum before the administration of antibiotics. Symptoms of upper respiratory illness (URI) among residents before the pneumonia outbreak corresponded with elevation of antibodies to human parainfluenza virus 1 (HPIV1). In a matched case-control study, six of 10 case-patients, compared with five of 20 controls, had symptoms of URI during the preceding month (matched odds ratio (MOR) = 4.5, 95% CI = 0.8-33). Nine case-patients had serum available, and five of these had both serologic evidence of recent HPIV1 infection and recent URI, compared with two of 18 controls (MOR = 9.0, 95% CI = 1.2-208). Only three residents had documentation of pneumococcal vaccination. CONCLUSIONS: Noninfluenza viral infections may play a role in the pathogenesis of some bacterial pneumonias. S. pneumoniae was the cause of at least two pneumonias; lack of preantibiotic cultures may have interfered with isolation of S. pneumoniae in others. Recent HPIV1 infection was epidemiologically linked to subsequently developing pneumonia. Spread of HPIV1 in the facility may have contributed to increased susceptibility to S. pneumoniae and, potentially, to other bacterial pathogens. 相似文献