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51.
Marinella Cappelletti Michael D. Kopelman John Morton Brian Butterworth 《Cognitive neuropsychology》2013,30(7):771-793
This study describes a 3-year follow-up investigation of the deterioration of number abilities in a semantic dementia patient (IH). A few studies have previously reported the decline of number knowledge in patients with degenerative disorders, although almost never in semantic dementia (Diesfeldt, 1993; Girelli, Luzzatti, Annoni, & Vecchi, 1999; Grafman, Kempen, Rosenberg, Salazar, & Boller, 1989). These studies described the change of the patients’ performance mainly in terms of increased errors in number tasks. On the other hand, dissociations between different types of number abilities, or different arithmetical operations, have been reported in patients with focal lesions. In the present investigation, the cognitive basis of number processing was revealed throughout the patient's cognitive decline. Two major results emerged from a longitudinal study: First, the patient's conceptual knowledge of arithmetic was well preserved despite severe impairment of nonarithmetic conceptual knowledge. Second, the patient's progressive decline revealed patterns of dissociations between different number abilities. These were between (1) multiplication and other arithmetical operations, which particularly emerged in the use of algorithms; (2) impaired knowledge of number facts and procedures on one hand, and conceptual knowledge of arithmetic on the other; and (3) different types of transcoding skills. The implications of these dissociations for the cognitive architecture of number processing are discussed. 相似文献
52.
Nicolas K Khattar Andrew C White Aurora S Cruz Shawn W Adams Kimberly S Meyer Haring JW Nauta Dale Ding Robert F James 《Interventional neuroradiology》2021,27(3):388
Ruptured vertebrobasilar dissecting aneurysms require urgent, often challenging treatment as they have with a high re-hemorrhage rate within the first 24 hours. The patient is a 57-year-old woman who presented with severe-sudden onset headache. Further work up showed a ruptured dissecting aneurysm of the caudal loop of the posterior inferior cerebellar artery (PICA) with associated narrowing distally, in the ascending limb. The aneurysm was immediately occluded with a Woven Endobridge (WEB) device (MicroVention, Tustin, CA, USA) while flow diversion treatment of the diseased ascending limb was postponed. Follow-up angiography three months later showed complete occlusion of the aneurysm, as well as healing of the diseased distal vessel, obviating the need for further intervention. WEB embolization of a ruptured dissecting posterior circulation aneurysm provided an excellent outcome for this patient. 相似文献
53.
Erythropoietin production in a primary culture of human renal carcinoma cells maintained in nude mice 总被引:4,自引:1,他引:4
The present studies report erythropoietin (Ep) production in primary cultures of a human renal carcinoma from a patient with erythrocytosis that has been serially transplanted to BALB/c nude mice. The levels of erythropoietin in the culture media were estimated using the exhypoxic polycythemic mouse assay (EHPCMA), fetal mouse liver erythroid colony- forming technique (FMLC), and a radioimmunoassay (RIA). The spent culture media of the exponentially growing cells contained less than 10 mU/ml of Ep measured by RIA. However, after the cells became confluent, Ep levels (RIA) in the spent media showed a marked increase to approximately 300 mU/ml. Ep levels estimated using the FMLC and EHPCMA were approximately 2/3 and 1/10, respectively, of those measured by RIA. Rabbit antiserum to highly purified human urinary Ep (70,400 U/mg protein) was utilized for immunocytochemical (peroxidase-antiperoxidase method) localization of Ep in the cultured cells. Very few of the cells in exponential growth exhibited Ep-like immunoreactivity, whereas intense Ep-like immunoreactivity was observed in the cytoplasm of the cells maintained in culture for a prolonged period after reaching confluency. The most intense staining was observed in some of the cells forming domes. The domes developed after the cells reached confluency, and their numbers increased with increasing time in confluent culture, in parallel with the increase in Ep levels in the spent media. This primary cell culture system of a renal cell carcinoma maintained in nude mice, which produces immunologically and biologically active Ep, may provide a useful model for studies of the mechanism of Ep production. 相似文献
54.
Immunoglobulin G from patients with heparin-induced thrombocytopenia binds to a complex of heparin and platelet factor 4 总被引:6,自引:3,他引:6
Heparin-induced thrombocytopenia (HIT) is an important complication of heparin therapy. Although there is general agreement that platelet activation in vitro by the HIT IgG is mediated by the platelet Fc receptor, the interaction among the antibody, heparin, and platelet membrane components is uncertain and debated. In this report, we describe studies designed to address these interactions. We found, as others have noted, that a variety of other sulfated polysaccharides could substitute for heparin in the reaction. Using polysaccharides selected for both size and charge, we found that reactivity depended on two independent factors: a certain minimum degree of sulfation per saccharide unit and a certain minimum size. Hence, highly sulfated but small (< 1,000 daltons) polysaccharides were not reactive nor were large but poorly sulfated polysaccharides. The ability of HIT IgG to recognize heparin by itself was tested by Ouchterlony gel diffusion, ammonium sulfate and polyethylene glycol precipitation, and equilibrium dialysis. No technique demonstrated reactivity. However, when platelet releasate was added to heparin and HIT IgG, a 50-fold increase in binding of radio-labeled heparin to HIT IgG was observed. The releasate was then depleted of proteins capable of binding to heparin by immunoaffinity chromatography. Only platelet factor 4-immunodepleted releasate lost its reactivity with HIT IgG and heparin. Finally, to determine whether the reaction occurred on the surface of platelets or in the fluid phase, washed platelets were incubated with HIT IgG or heparin and after a wash step, heparin or HIT IgG was added, respectively. Reactivity was only noted when platelets were preincubated with heparin. Consistent with these observations was the demonstration of the presence of PF4 on platelets using flow cytometry. These studies indicate that heparin and other large, highly sulfated polysaccharides bind to PF4 to form a reactive antigen on the platelet surface. HIT IgG then binds to this complex with activation of platelets through the platelet Fc receptors. 相似文献
55.
Busch MP; Laycock M; Kleinman SH; Wages JW Jr; Calabro M; Kaplan JE; Khabbaz RF; Hollingsworth CG 《Blood》1994,83(4):1143-1148
Blood donations in the United States have been screened for antibody to human T-lymphotropic virus type I (HTLV-I) by HTLV-I enzyme immunoassay (EIA) since November 1988. Specimens repeatedly found to be reactive by EIA undergo confirmation by supplementary serologic tests. We assessed the accuracy of blood center testing of 994 HTLV-I EIA repeat-reactive specimens in five US blood centers between November 1988 and December 1991. Of 410 confirmed HTLV-I/II donations, 407 (99.3%) were infected with HTLV-I/II, as determined by polymerase chain reaction (PCR) (403 cases) and by repeat serologic testing (4 cases). The three false- positive results occurred in the first year of testing. Of 425 HTLV- indeterminate specimens, 6 (1.4%) were found to be infected by PCR (5 with HTLV-II and 1 with HTLV-I). None of 159 confirmatory test-negative donations was PCR positive. Of HTLV-I/II-seropositive specimens, 80.2% to 95.4% could be typed as HTLV-I or HTLV-II by type-specific serologic assays. These results support recommendations that HTLV-I/II- seropositive donors should be advised that they are infected with HTLV- I, HTLV-II, or HTLV-I/II (depending on results of type-specific assays). HTLV-indeterminate donors should be advised that their results only rarely indicate HTLV infection. HTLV confirmatory test-negative donors should be reassured that they are not infected with HTLV-I or HTLV-II. 相似文献
56.
Joanne E Butterworth John L Campbell 《The British journal of general practice》2014,64(628):e709-e718
Background
Older patients differ from younger patients in their perceptions of trust in doctors; their sense of shared decision making is particularly associated with their trust in the GP. Enhancing trust and improving shared decision making are thought to have positive health outcomes. Older patients are sometimes reported as being less frequently involved in decisions about their health care, however, and in having more unmet healthcare needs than younger patients.Aim
This study explored older patients’ trust in their GPs and their perceptions of shared decision making.Design and setting
Qualitative methods were used. Systematic sampling identified 20 participants, aged ≥65 years, from three GP surgeries in Devon, UK.Method
A constant comparative approach was applied to thematic analysis of transcribed interviews.Results
All participants valued feeling involved in decisions but differed regarding how they felt involved. Trust influenced preferences for shared decision making: a trusted GP ‘ally’, to competently manage participants’ increasing health-information requirements throughout the vulnerable ageing process, was important. Trust was affected by factors contributing to the facilitation of involvement. GP characteristics, communication skills, consultation duration, and continuity of care were common themes.Conclusion
Although limited geographically and subsequently by ethnic group, the present sample allows for reasonable transferability of the study to other UK populations. A range of factors are highlighted for consideration when planning primary healthcare delivery: to facilitate the optimal involvement of older patients in decisions about their health care, while enhancing their trust in the GP; to help minimise potential health inequalities for this patient group. 相似文献57.
ILR Genetics Consortium Emerging Risk Factors Collaboration Sarwar N Butterworth AS Freitag DF Gregson J Willeit P Gorman DN Gao P Saleheen D Rendon A Nelson CP Braund PS Hall AS Chasman DI Tybjærg-Hansen A Chambers JC Benjamin EJ Franks PW Clarke R Wilde AA Trip MD Steri M Witteman JC Qi L van der Schoot CE de Faire U Erdmann J Stringham HM Koenig W Rader DJ Melzer D Reich D Psaty BM Kleber ME Panagiotakos DB Willeit J Wennberg P Woodward M Adamovic S Rimm EB Meade TW Gillum RF Shaffer JA 《Lancet》2012,379(9822):1205-1213
58.
Modern population based oral health management requires a complete understanding of the impact of disease in order to provide efficient and effective oral health care and guidance. Periodontitis is an important cause of tooth loss and has been shown to be associated with a number of systemic conditions. The impact of oral conditions and disorders on quality of life has been extensively studied. However, the impact of periodontitis on quality of life has received less attention. This review summarizes the literature on the impact of periodontitis on oral health‐related quality of life (OHRQoL). Relevant publications were identified after searching the MEDLINE and EMBASE electronic databases. Screening of titles and abstracts and data extraction was conducted. Only observational studies were included in this review. Most of the reviewed studies reported a negative impact of periodontitis on OHRQoL. However, the reporting standards varied across studies. Moreover, most of the studies were conducted in developed countries. 相似文献
59.
Peter A Lazzarini Julia Geraghty Ewan M Kinnear Mark Butterworth Donna Ward 《Journal of foot and ankle research》2013,6(1):1-11
Background
Research is a major driver of health care improvement and evidence-based practice is becoming the foundation of health care delivery. For health professions to develop within emerging models of health care delivery, it would seem imperative to develop and monitor the research capacity and evidence-based literacy of the health care workforce. This observational paper aims to report the research capacity levels of statewide populations of public-sector podiatrists at two different time points twelve-months apart.Methods
The Research Capacity & Culture (RCC) survey was electronically distributed to all Queensland Health (Australia) employed podiatrists in January 2011 (n?=?58) and January 2012 (n?=?60). The RCC is a validated tool designed to measure indicators of research skill in health professionals. Participants rate skill levels against each individual, team and organisation statement on a 10-point scale (one?=?lowest, ten?=?highest). Chi-squared and Mann Whitney U tests were used to determine any differences between the results of the two survey samples. A minimum significance of p?<?0.05 was used throughout.Results
Thirty-seven (64%) podiatrists responded to the 2011 survey and 33 (55%) the 2012 survey. The 2011 survey respondents reported low skill levels (Median?<?4) on most aspects of individual research aspects, except for their ability to locate and critically review research literature (Median?>?6). Whereas, most reported their organisation’s skills to perform and support research at much higher levels (Median?>?6). The 2012 survey respondents reported significantly higher skill ratings compared to the 2011 survey in individuals’ ability to secure research funding, submit ethics applications, and provide research advice, plus, in their organisation’s skills to support, fund, monitor, mentor and engage universities to partner their research (p?<?0.05).Conclusions
This study appears to report the research capacity levels of the largest populations of podiatrists published. The 2011 survey findings indicate podiatrists have similarly low research capacity skill levels to those reported in the allied health literature. The 2012 survey, compared to the 2011 survey, suggests podiatrists perceived higher skills and support to initiate research in 2012. This improvement coincided with the implementation of research capacity building strategies. 相似文献60.
J. Butterworth Trent Cross William Butterworth Paul Mousa S. Thomas 《International journal of surgery case reports》2013,4(7):568-570
INTRODUCTIONTransmesenteric herniae are a rare cause of bowel ischaemia in adults with few reported cases in published literature.PRESENTATION OF CASEWe report a rare case of a 26-year-old female with spontaneous transmesenteric hernia of jejunum and proximal ileum due to a congenital mesenteric defect resulting in bowel gangrene, presenting initially with no haemodynamic or biochemical abnormalities. The hernia was reduced, small bowel resected and primary side to side anastomosis performed, following which the patient made a good recovery and was discharged 5 days later.DISCUSSIONThe insidious onset of transmesenteric herniae and lack of specific radiological or laboratory investigations reaffirms the importance of surgeons maintaining a high index of suspicion for this critical surgical emergency.CONCLUSIONClose monitoring of the patient's general condition in cases of non-specific abdominal pain is essential to identify the rare deteriorating patient for early surgical intervention and optimal outcome. 相似文献