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41.
42.
Atul Maheshwari Michael Fischer Pierluigi Gambetti Alicia Parker Aarthi Ram Claudio Soto Luis Concha-Marambio Yvonne Cohen Ermias D. Belay Ryan A. Maddox Simon Mead Clay Goodman Joseph S. Kass Lawrence B. Schonberger Haitham M. Hussein 《Emerging infectious diseases》2015,21(5):750-759
Variant Creutzfeldt-Jakob disease (vCJD) is a rare, fatal prion disease resulting from transmission to humans of the infectious agent of bovine spongiform encephalopathy. We describe the clinical presentation of a recent case of vCJD in the United States and provide an update on diagnostic testing. The location of this patient’s exposure is less clear than those in the 3 previously reported US cases, but strong evidence indicates that exposure to contaminated beef occurred outside the United States more than a decade before illness onset. This case exemplifies the persistent risk for vCJD acquired in unsuspected geographic locations and highlights the need for continued global surveillance and awareness to prevent further dissemination of vCJD. 相似文献
43.
Muscle activity during chest wall restriction and positive pressure breathing in man. 总被引:3,自引:0,他引:3
The effects of sustained constriction of the rib cage (RCC), constriction of the abdomen (AC) and of breathing against a positive pressure of 10 cms of water (PPB) were studied in four normal subjects with moderate constant hypercapnia. Intercostal electrical activity (Eic) was measured by implanted wire electrodes and diaphragmatic electrical activity (Edia) by oesophageal electrodes. There was no fixed relation between Edia and VT. VT was unaltered during AC and RCC: Edia was unaltered during AC but increased during RCC. The response to PPB without constriction varied: three subjects increased end-expiratory VL with increase in Edia and inspiratory Eic. One subject initially, and one subject after training, maintained end-expiratory VL constant with no change in Edia and an increase in expiratory Eic. When PPB was applied during AC and RCC there was an increase in Edia proportional to end-expiratory lung volume. The overall response to distortion was determined by voluntary choice, but muscle electrical activity reflected chest wall configuration: when the diaphragm was shorter and at a mechanical disadvantage its electrical activity increased. This was compatible with a reflex with afferent information from diaphragm tendon organ and muscle spindle receptors. 相似文献
44.
Lyle R. Petersen R.Hardwin Mead Mark G. Perlroth 《The American journal of medicine》1983,75(1):166-170
A 48-year-old actively homosexual man who had undergone liver transplantation for cirrhosis secondary to hepatitis B infection six years previously presented with a syndrome of diffuse pain, cholestasis, and low-grade fever. The development of thrombocytopenia and persistent hypoprothrombinemia precluded liver biopsy. Subsequently, a skin eruption and VDRL result of 1:128 indicated that most of the findings could be explained by a diagnosis of secondary syphilis with luetic hepatitis and periostitis. This impression was confirmed by a complete response to penicillin therapy. The relation of thrombocytopenia to lues in this case remains uncertain. 相似文献
45.
46.
Ingela Schnittger Peter J. Fitzgerald George T. Daughters Neil B. Ingels Niki E. Kantrowitz Anne Schwarzkopf Carol W. Mead Richard L. Popp 《The American journal of cardiology》1982,50(3):512-519
Measurement of left ventricular volume at end-diastole or end-systole with both two dimensional echocardiography and either Cineangiography or radionuclide scans, not recorded simultaneously, has shown large echocardiographic underestimation of volumes even in normal ventricles. In this study fluoroscopic and two dimensional echocardiographic recordings were obtained in 18 patients with abnormal wall motion and previously implanted myocardial markers. The echocardiographic values for volume and those derived from myocardial markers correlated well (r = 0.87), and there were no statistically significant differences in values obtained with the two methods at end-diastole or end-systole. The ejection fractions obtained with two dimensional echocardiography (mean ± standard deviation 46 ± 7 percent) and with fluoroscopic recording of the markers (41 ± 9 npercent) did not differ statistically.These results were compared with those in another 18 patients (nine with abnormal wall motion) having two dimensional echocardiography within 24 hours of a 30 ° right anterior oblique contrast left ventriculogram. Again, two dimensional echocardiographic ventricular volume correlated well with the angiographic volume (r = 0.85), although echocardiographic end-diastolic volume was consistently 20 percent less than angiographic end-diastolic volume (p < 0.01). Ejection fraction obtained with echocardiography (47 ± 8 percent) was less than that obtained with angiography (60 ± 7 percent) (p < 0.001). Interobserver variability in calculating volume with echocardiography was 4 percent.Probable reasons for the lack of severe underestimation of volume with echocardiography even in very abnormal ventricles, relative to that demonstrated in prior reports, include improvements in ultrasonic beam width, tracing method, transducer position and scan plane orientation within the ventricle. In addition, the possible effects of angiographic dye in the ventricular trabeculae are discussed and the effect of simultaneous studies by two different methods are compared. 相似文献
47.
Exceptional record of mid-Pleistocene vertebrates helps differentiate climatic from anthropogenic ecosystem perturbations 下载免费PDF全文
Barnosky AD Bell CJ Emslie SD Goodwin HT Mead JI Repenning CA Scott E Shabel AB 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(25):9297-9302
Mid-Pleistocene vertebrates in North America are scarce but important for recognizing the ecological effects of climatic change in the absence of humans. We report on a uniquely rich mid-Pleistocene vertebrate sequence from Porcupine Cave, Colorado, which records at least 127 species and the earliest appearances of 30 mammals and birds. By analyzing >20,000 mammal fossils in relation to modern species and independent climatic proxies, we determined how mammal communities reacted to presumed glacial-interglacial transitions between 1,000,000 and 600,000 years ago. We conclude that climatic warming primarily affected mammals of lower trophic and size categories, in contrast to documented human impacts on higher trophic and size categories historically. Despite changes in species composition and minor changes in small-mammal species richness evident at times of climatic change, overall structural stability of mammal communities persisted >600,000 years before human impacts. 相似文献
48.
Mead AJ Gale RE Kottaridis PD Matsuda S Khwaja A Linch DC 《British journal of haematology》2008,141(4):454-460
FLT3 tyrosine kinase domain mutations (FLT3/TKDs) are associated with a favourable prognosis in acute myeloid leukaemia (AML), unlike FLT3 internal tandem duplications (FLT3/ITDs) that have a poor prognosis. Whilst FLT3/ITD+ cells are more susceptible to the cytotoxic effects of FLT3 inhibitors than wild type (WT) cells, the sensitivity of FLT3/TKD+ cells to therapeutic agents is unclear, as is the importance of the mutant level. We therefore studied the effect of cytarabine and the FLT3 inhibitor lestaurtinib, either alone or in combination, on in vitro survival of blast cells from 36 cases of AML (14 FLT3/WT, 11 FLT3/ITD+ and 11 FLT3/TKD+). All three groups showed similar sensitivity to the cytotoxic effects of cytarabine but FLT3/ITD mutant level was inversely correlated with cytarabine cytotoxicity (P = 0.04) whereas FLT3/TKD mutant level had no impact. FLT3/TKD+ cells showed a similar response to lestaurtinib as FLT3/WT cells, whereas FLT3/ITD+ cells were more sensitive (P = 0.004). There was no correlation between mutant level and lestaurtinib sensitivity for either FLT3/ITD+ or FLT3/TKD+ cells. Synergistic cytotoxicity of lestaurtinib plus cytarabine was demonstrated in all three groups. These results suggest that FLT3/TKD+ and FLT3/WT cases should not be differentiated when considering patients for treatment with FLT3 inhibitors. 相似文献
49.
Apperson CS Engber B Nicholson WL Mead DG Engel J Yabsley MJ Dail K Johnson J Watson DW 《Vector borne and zoonotic diseases (Larchmont, N.Y.)》2008,8(5):597-606
Cases of Rocky Mountain spotted fever (RMSF) in North Carolina have escalated markedly since 2000. In 2005, we identified a county in the Piedmont region with high case numbers of RMSF. We collected ticks and examined them for bacterial pathogens using molecular methods to determine if a novel tick vector or spotted fever group rickettsiae (SFGR) might be emerging. Amblyomma americanum, the lone star tick, comprised 99.6% of 6,502 specimens collected in suburban landscapes. In contrast, Dermacentor variabilis, the American dog tick, a principal vector of Rickettsia rickettsii, comprised < 1% of the ticks collected. Eleven of 25 lone star tick pools tested were infected with "Rickettsia amblyommii," an informally named SFGR. Sera from patients from the same county who were presumptively diagnosed by local physicians with a tick-borne illness were tested by an indirect immunofluorescence antibody (IFA) assay to confirm clinical diagnoses. Three of six patients classified as probable RMSF cases demonstrated a fourfold or greater rise in IgG class antibody titers between paired acute and convalescent sera to "R. amblyommii" antigens, but not to R. rickettsii antigens. White-tailed deer, Odocoileus virginianus, are preferred hosts of lone star ticks. Blood samples collected from hunter-killed deer from the same county were tested by IFA test for antibodies to Ehrlichia chaffeensis and "R. amblyommii." Twenty-eight (87%) of 32 deer were positive for antibodies to E. chaffeensis, but only 1 (3%) of the deer exhibited antibodies to "R. amblyommii," suggesting that deer are not the source of "R. amblyommii" infection for lone star ticks. We propose that some cases of rickettsiosis reported as RMSF may have been caused by "R. amblyommii" transmitted through the bite of A. americanum. 相似文献
50.
Teri L McKenzie G Logsdon RG McCurry SM Bollin S Mead J Menne H 《The Gerontologist》2012,52(4):452-459
The need for evidence-based non-pharmacological community programs to improve care of older adults with dementia is self-evident, considering the sheer numbers of affected individuals; the emotional, physical, and financial toll on affected individuals and their caregivers; the impact on our health care system; and the growing availability of evidence regarding the potential for psychosocial interventions to enhance care and decrease costs. To address this need, the Administration on Aging has begun funding translation of evidence-based programs into community settings. Two programs, Reducing Disability in Alzheimer's Disease and STAR-Community Consultants (STAR-C), were selected by the Ohio Department of Aging (in collaboration with the Alzheimer's Association Chapters in Ohio) and the Oregon Department of Health Services (in partnership with Area Agencies on Aging and the Oregon Chapter of the Alzheimer's Association) to be implemented by their staff. Both programs are designed to improve care, enhance life quality, and reduce behavioral problems of persons with dementia and have demonstrated efficacy via randomized controlled trials. This article addresses the developmental and ongoing challenges encountered in the translation of these programs to inform other community-based organizations considering the translation of evidence-based programs and to assist researchers in making their work more germane to their community colleagues. 相似文献