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71.
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
72.
E.F. de Maar E.A.M. Verschuuren J.J. Homan vd Heide D.M. Kas-Deelen D. Jagernath T.H. The R.J. Ploeg W.J. van Son 《Transplant infectious disease》2002,4(1):17-24
Abstract: Background. In this retrospective single center study we have evaluated the relation between the immunosuppressive regimen and the incidence and characteristics of cytomegalovirus (CMV) infection in the setting without CMV prophylaxis from 1989 through 1998. Methods. All (470) first cadaveric renal transplantations in nonsensitized (PRA < 60%) patients were analyzed. Immunosuppression consisted of cyclosporine A (Sandimmune) and prednisolone from 1989 through 2-1993 (S; 189 patients), of cyclosporine microemulsion (Neoral) and prednisolone from 3-1993 through 5-1997 (N; 200 patients) and of mycophenolate mofetil, Neoral and prednisolone from 5-1997 until 1998 (M; 81 patients). The CMV pp65-antigenemia was measured routinely at least once weekly from day 10 till 12 weeks after transplantation or until pp65-antigenemia became negative. No CMV-prophylaxis was given. Results. By changing from Sandimmune to Neoral and by adding mycophenolate mofetil, respectively, we observed a higher frequency of especially secondary CMV infections (S vs. N vs. M, respectively, 28 vs. 50 vs. 63%, P = 0.026; S vs. N, P = 0.027; S vs. M, P = 0.015; and N vs. M, n.s). The CMV infections lasted longer (median duration antigenemia S vs. N vs. M, respectively, 3 vs. 5 vs. 7 weeks, P = 0.0003; S vs. N, P < 0.002; S vs. M, P < 0.001; and N vs. M, P < 0.05). Viral load was higher in M (median maximal pp65-antigenemia S vs. N vs. M, respectively, 19 vs. 14.5 vs. 73, P < 0.01; S vs. N, n.s.; S vs. M, P < 0.001 and N vs. M, P < 0.01). Conclusions. The use of Neoral and the addition of mycophenolate mofetil caused significant changes in the incidence, duration and viral load of CMV infections. 相似文献
73.
A case of constrictive pericarditis which developed after the onset of clinical manifestation of tuberculous pericarditis was reported. A 75-year-old male, complaining of anorexia, was admitted to our hospital. Adenosinedeaminase (ADA) level in pericardial effusion was found to be increased, and the culture of pericardial effusion was positive for tubercle bacilli. Diagnosed as having tuberculous pleuritis and pericarditis, he underwent chemotherapy for tuberculosis. However, massive pleural effusion developed later and pleural effusion drainage was carried out. Despite repeated drainage, pleural effusion continued to recur. Chest CT revealed apparent pericardial thickening, in addition, cardiac catheterization revealed elevation of mean right atrial pressure and marked deterioration of cardiac functions including decrease of cardiac output. These findings were compatible with constrictive pericarditis. After these investigations a diagnosis of constrictive pericarditis was established, and the patient underwent a pericardiectomy. Pathological examination of resected specimens revealed tuberculous inflammation. 相似文献
74.
Kwon HS Cho JH Kim HS Lee JH Song BR Oh JA Han JH Kim HS Cha BY Lee KW Son HY Kang SK Lee WC Yoon KH 《Diabetes research and clinical practice》2004,66(Z1):S133-S137
We developed a blood glucose management system using the Internet and short message service (SMS) which can lessen the social economic burden and materialize an individualized diabetes mellitus management. A total of 185 diabetic patients participated in this study and their mean age was 42.4 years old (8-79 year-old). Participants sent their self-measured blood glucose levels, medication and its dosages, amount of meal, and degree of exercise to their health providers in this specialized web-based diabetes management system for 3 months. The health providers consisting of endocrinology specialists, dietitians, and nurses sent recommendations for individualized diabetes management according to the data on the web. Laboratory tests including lipid profiles and glycated hemoglobin (HbA1c), and a survey of satisfaction about this system were performed before and after the study period. The mean HbA1c improved from 7.5 +/- 1.5 to 7.0 +/- 1.1% after using the management program (P = 0.003). The mean serum triglyceride and HDL-cholesterol levels turned for the better also. HbA1c improved from 8.4 +/- 1.2 to 7.5 +/- 1.0% after applying this program to patients with the HbA1c of 7% or higher at baseline (P = 0.010). We propose this web-based diabetic patient management system as a new tool for communication between health care providers and patients. 相似文献
75.
76.
Antibiotic therapy for inpatients with community‐acquired pneumonia in a developing country
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79.
Jin Yong Lee Sang Jun Eun Minsu Ock Hyun Joo Kim Hyeon-Jeong Lee Woo-Seung Son Min-Woo Jo 《Journal of Korean medical science》2015,30(5):523-532
Although primary care has been recognized as an essential element of the healthcare system, the primary healthcare of Korea has not been highly valued. Listening to the voices of physicians who are engaged in primary care should be the first step for improving the level of primary care in Korea. In this study, we conducted a questionnaire survey of general internists to investigate their perspectives regarding primary care, and which included the evaluation of current primary care, perception of the five, key attributes of primary care, and their opinions regarding the management system of chronic diseases. A total of 466 general internists'' responses were used in this analysis. The results showed that primary care is considered to have an important role, according to general internists, although their evaluation of the overall status of primary care in Korea indicated that it is poor. The respondents also indicated that the functions of coordination and comprehensiveness in primary care, which can be integral for treating patients with chronic diseases, are most vulnerable. Given the high level of agreement regarding the need for a new medical management system for chronic diseases, based on physicians'' autonomy and provided by clinics, establishing a policy encouraging the participation of general internists should be emphasized.
Graphical Abstract
相似文献80.
A selective role of calcineurin aalpha in synaptic depotentiation in hippocampus 总被引:1,自引:0,他引:1
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Zhuo M Zhang W Son H Mansuy I Sobel RA Seidman J Kandel ER 《Proceedings of the National Academy of Sciences of the United States of America》1999,96(8):4650-4655
Pharmacological studies have suggested that long-term potentiation (LTP) and long-term depression (LTD) and depotentiation, three forms of synaptic plasticity in the hippocampus, require the activity of the phosphatase calcineurin. At least two different isoforms of calcineurin are found in the central nervous system. To investigate whether all of these forms of synaptic plasticity require the same isoforms of calcineurin, we have examined LTD, depotentiation, and LTP in mice lacking the predominant calcineurin isoform in the central nervous system, Aalpha-/- mice. Depotentiation was abolished completely whereas neither LTD nor LTP were affected. These studies provide genetic evidence that the Aalpha isoform of calcineurin is important for the reversal of LTP in the hippocampus and indicate that depotentiation and LTD operate through somewhat different molecular mechanisms. 相似文献