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51.
In the human erythrocyte membrane phosphatidylcholine and sphingomyelin reside mainly in the outer leaflet, whereas the aminophospholipids, phosphatidylethanolamine and phosphatidylserine, are mainly found in the inner leaflet. Maintenance of phospholipid asymmetry has been assumed to involve interactions between the aminophospholipids and the membrane skeleton, in particular spectrin. To investigate whether spectrin contributes to maintaining the phospholipid transbilayer distribution and kinetics of redistribution, we studied erythrocytes from hereditary spherocytosis patients whose spectrin levels ranged from 34% to 82% of normal. The phospholipid composition and the accessibility of membrane phospholipids to hydrolysis by phospholipases were in the normal range. Spin-labeled phosphatidylserine and phosphatidylethanolamine analogues that had been introduced into the outer leaflet were rapidly transported at 37 degrees C to the inner leaflet, whereas the redistribution of spin-labeled phosphatidylcholine was slower. The kinetics of transbilayer movement of these spin-labeled phospholipid in all samples was in the normal range and was not affected by the level of spectrin. Although these erythrocyte membranes contained as little as 34% of the normal level of spectrin and were characterized by several physical abnormalities, the composition, distribution, and transbilayer kinetics of the phospholipids were found to be normal. We therefore conclude that spectrin plays, at best, only a minor role in maintaining the distribution of erythrocyte membrane phospholipid. 相似文献
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Shaik Mohamed Asif Shaik Mohamed Shamsudeen Khalil Ibrahim Assiri Hussain Mohammed Al Muburak Sultan Mohammed Kaleem Abdul Ahad Khan Mansoor Shariff 《Medicine》2021,100(17)
Introduction:Drug induced oral erythema multiforme a rare clinical entity which involves only the lips and oral mucosa without skin involvement. These lesions are difficult in diagnosing with other oral ulcerative lesions with similar clinical manifestations.Patient concerns:This article presents 2 case reports of Oral erythema multiforme in which drugs were the precipitating factor. Its etiopathogenesis, differential diagnosis and treatment modalities of the disease is discussed.Diagnosis:Based on patient''s complaints, drug history and clinical appearance, provisional diagnosis of drug induced erythema multiforme was considered.Intervention:For case 1, patient was instructed to discontinue usage of drug and prescribed systemic steroid (Prednisolone 10 mg/d) for a week along with germicidal drugs to prevent secondary infection. Medication was tapered to 5 mg/d after first week.For case 2, patient was instructed to discontinue the drug and systemic steroid prednisolone 20 mg /d for 1 week with tapering dose of 10 mg/d for the second week was administered.Outcome:For case 1 and case 2 healing of the lesions were evident on third week of follow up.Conclusion:Medications should be taken under medical supervision. Over the counter drugs might lead to allergic reactions like drug induced oral erythema multiforme, which is a rare variant and needs to be differentiate from other oral ulcerative lesion for prompt management and follow-up. 相似文献
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N Alrashdi Mousa Saleh Alanazi Majed Khalid Almoaqly Alshaya Abdulrahman Khaled Alanazi Sultan Mahja Marzouq 《Clinical rheumatology》2022,41(5):1577-1582
Clinical Rheumatology - Coronavirus disease-19 (COVID-19) is a global pandemic that is caused by COVID-19 virus, which was initially identified in December 2019 in Wuhan, China. Vaccination is one... 相似文献
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Styles LA; Schalkwijk CG; Aarsman AJ; Vichinsky EP; Lubin BH; Kuypers FA 《Blood》1996,87(6):2573-2578
Acute chest syndrome (ACS) is associated with significant morbidity and is the leading cause of death in patients with sickle cell disease (SCD). Recent reports suggest that bone marrow fat embolism can be detected in many cases of severe ACS. Secretory phospholipase A2 (sPLA2) is an important inflammatory mediator and liberates free fatty acids, which are felt to be responsible for the acute lung injury of the fat embolism syndrome. We measured SPLA2 levels in 35 SCD patients during 20 admissions for ACS, 10 admissions for vaso-occlusive crisis, and during 12 clinic visits when patients were at the steady state. Eleven non-SCD patients with pneumonia were also evaluated. To determine if there was a relationship between sPLA2 and the severity of ACS we correlated SPLA2 levels with the clinical course of the patient. In comparison with normal controls (mean = 3.1 +/- 1.1 ng/mL), the non- SCD patients with pneumonia (mean = 68.6 +/- 82.9 ng/mL) and all three SCD patient groups had an elevation of SPLA2 (steady state mean = 10.0 +/- 8.4 ng/mL; vaso-occlusive crisis mean = 23.7 +/- 40.5 ng/mL; ACS mean = 336 +/- 209 ng/mL). In patients with ACS sPLA2 levels were 100- fold greater than normal control values, 35 times greater than values in SCD patients at baseline, and five times greater than non-SCD patients with pneumonia. The degree of SPLA2 elevation in ACS correlated with three different measures of clinical severity and, in patients followed sequentially, the rise in SPLA2 coincided with the onset of ACS. The dramatic elevation of SPLA2 in patients with ACS but not in patients with vaso-occlusive crisis or non-SCD patients with pneumonia and the correlation between levels of SPLA2 and clinical severity suggest a role for SPLA2 in the diagnosis and, perhaps, in the pathophysiology of patients with ACS. 相似文献
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Barbara A. Curbow Amy B. Dailey Evelyn C. King-Marshall Tracy E. Barnett Jessica R. Schumacher Shahnaz Sultan Thomas J. George Jr. 《American journal of public health》2015,105(4):e103-e111
Objectives. We aimed to highlight sociodemographic differences in how patients access colonoscopy.Methods. We invited all eligible patients (n = 2500) from 2 academy-affiliated colonoscopy centers in Alachua County, Florida (1 free standing, 1 hospital based), to participate in a precolonoscopy survey (September 2011–October 2013); patients agreeing to participate (n = 1841, response rate = 73.6%) received a $5.00 gift card.Results. We found sociodemographic differences in referral pathway, costs, and reasons associated with obtaining the procedure. Patients with the ideal pathway (referred by their regular doctor for age-appropriate screening) were more likely to be Black (compared with other minorities), male, high income, employed, and older. Having the colonoscopy because of symptoms was associated with being female, younger, and having lower income. We found significant differences for 1 previously underestimated barrier, having a spouse to accompany the patient to the procedure.Conclusions. Patients’ facilitators and barriers to colonoscopy differed by sociodemographics in our study, which implies that interventions based on a single facilitator will not be effective for all subgroups of a population.Colorectal cancer (CRC), the second leading cause of US cancer deaths in 2013 (50 830),1 is not distributed equally. Nationally, it is estimated that incidence is 25% higher, and mortality from CRC 50% higher, in Black Americans than in Whites.2,3 Most CRC diagnoses follow evaluation by colonoscopy. Although consumers have a range of CRC screening tests, from least invasive (fecal occult blood test, fecal immunochemical test) to most invasive (sigmoidoscopy, colonoscopy),4 if polyps are indicated, a colonoscopy is required as follow-up. Thus, colonoscopy is both an entry point and a pivotal event in the process of preventing, detecting, and treating CRC. CRC can be prevented through the removal of precancerous polyps or detected at an early, easily treatable stage5; findings indicate6 that colonoscopy with polypectomy reduces mortality from CRC by 53%. Although rates of CRC screening have increased,3 there is need for improvement. More than one third of Americans are not in compliance with screening guidelines,7 with rates being lower in the southern United States.8In 2008, Etzioni et al.9 presented a model of patient and provider-level factors that influence decision-making in colon cancer and that can lead to health disparities in disease recurrence and survival. The Etzioni model identifies key points of vulnerability in the treatment process where the potential to achieve high-quality, guideline-recommended care can be lost. The model captures patients after surgery, beginning with the decision to refer patients to a medical oncologist for adjuvant treatment; it is relevant because there is considerable evidence of inequities in who receives adjuvant treatment based on older age,10,11 comorbidities,12,13 low income,7 coverage with Medicaid rather than Medicare,13 Black race,14 female gender,15,16 and being unmarried.9We propose that this model starts too late in the process; health disparities originate prior to colonoscopy and can increase at each decision point along a continuum. In an elaborated model (Figure 1), we suggest that CRC health disparities research should begin with an investigation of entry into the health care system and the subsequent pathways to colonoscopy. Referral patterns, costs, and patient demographics influence patient access to care, colonoscopy compliance, and postcolonoscopy decision-making.Open in a separate windowFIGURE 1—Pathways to colonoscopy, treatment, and outcomes. 相似文献
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该研究以山东万杰医学院为例,针对目前招生规模越来越大,生源质量不断下滑,大面积学生逃学、厌学、考试成绩不及格的严峻现实,提出有关教学方法、教学内容和考核方式的教学三项改革,这三项改革举措顺应了当前高校教育(特别是民办高校教育)形势的发展趋势。通过改革实践,已初见成效,进一步验证了只有坚定不移地搞好教学三项改革,才能保证和提高教学质量,从而使广大学生及其家长的利益得到充分保障;也只有大张旗鼓地继续搞好教学三项改革,学校才有生存和可持续发展的空间。 相似文献