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21.
Improving the safety of patient care is an issue which affects health systems in both developed and developing countries. To co-ordinate and accelerate improvements in patient safety, the World Health Organization (WHO) has supported the creation of the World Alliance for Patient Safety which was launched in October 2004. The six action areas of the Alliance are Patients for Patient Safety, Taxonomy, Research, Solutions for Patient Safety, Reporting and Learning, and a biennial Global Patient Safety Challenge. The first Challenge covering 2005-2006 was launched in October 2005 under the banner 'Clean Care is Safer Care'. The Challenge addresses health care-associated infection, a major, patient safety problem affecting hundreds of millions of people worldwide. 相似文献
22.
23.
Platelet additive solutions (PASs) were first developed in the 1980s, and continued to be improved over the following years. The use of PASs as replacement for plasma has a number of benefits, both for the quality of the platelet concentrates and for the patients. However, some PASs have been associated with a lower platelet yield in the PCs, a shorter storage time, and a lower increment in the patient when compared to PCs in plasma. A number of reformulations of the PASs have taken place to counteract these disadvantages. Most PASs use acetate as nutrient for the platelets, which has the benefit of generating bicarbonate when oxidized by the platelets, thus supplying its own buffering capacity. Alternatively, glucose is used, but may cause deterioration of pH in the stored PCs due to the formation of lactic acid. Addition of other buffering substances, such as phosphate, can be added to ensure maintenance of neutral pH. An important finding was the inhibiting effect of potassium and magnesium on platelet activation. The initially developed PASs lacked these two ingredients and showed reduced storage times of the PCs in PAS when compared to those stored in plasma. However, when these constituents are included in the PAS, storage time is similar and even exceeds those seen for PCs in plasma. Considerable research is done in further formulating the optimal PAS. Bicarbonate is being considered as buffer for these PASs. Also, L-carnitine appears to have a favorable effect on stored platelets, including a reduction of platelet metabolism, and inhibition of apoptosis. Another area of optimization is lowering of plasma content needed for maintaining platelet quality. Where current PASs still need at least 30% residual plasma, there is a trend towards lowering the plasma content to less than 5% with the newer PASs. Preservation of purinergic platelet receptor functionality by ADP-degrading activities in plasma appears to play an important role in this respect. Development of PASs are usually based on in vitro studies alone. It is important to realize that only clinical studies can give definitive answers about the quality of platelets stored in PASs. Sofar, only limited clinical evaluations have been published that either studied the effectiveness of platelets in initially-developed PASs, or were specifically done in combination with pathogen reduction technologies. Thus, PASs seem to be an excellent replacement for (part of) the plasma when producing PCs, and allow extended storage with maintenance of quality, but more clinical studies are needed to substantiate in vitro results. 相似文献
24.
Joachim H?chel D?rte Lehmann Claudia Fehrenberg Volker Unger David A Groneberg Christian Grosse-Siestrup 《Nephrology, dialysis, transplantation》2003,18(9):1748-1754
BACKGROUND: The isolated perfused canine kidney has been established as a valid model for conducting both renal physiology and transplantation research. This model is of particular importance for developing new strategies to improve graft function after renal transplantation. In the present study, a newly developed method using isolated haemoperfused porcine kidneys was adapted for use in canine kidneys. In contrast to haemoperfusion, synthetic perfusion media can be standardized and can prevent the initiation of blood-mediated reperfusion reactions. Thus, an additional aim was to determine whether blood could be replaced by synthetic cell-free perfusion solutions. METHODS: Canine kidneys (n = 30) were harvested from donors euthanized in veterinary practices for causes unrelated to the present study. The kidneys were isolated and perfused with autologous blood or cell-free synthetic electrolyte buffer (Tyrode solution). During perfusion, we monitored renal perfusate flow (RPF), glomerular filtration rate (GFR), electrolyte and glucose reabsorption, oxygen consumption and urine concentration. RESULTS: Changes in perfusion medium did not affect the RPF. In contrast, GFR, urine concentration and oxygen consumption were significantly higher, whereas fractional excretion of sodium and glucose were significantly lower in blood- than in Tyrode-perfused kidneys. CONCLUSIONS: This system offers a simple model for studying whole-organ functional alterations after acute renal ischaemia. Renal function indicators were below values reported during in vivo physiological conditions. These functions were better conserved when kidneys were perfused with autologous blood than with Tyrode. 相似文献
25.
Natural interferon enhances expression of placental alkaline phosphatase in human seminoma xenograft
T. Imao K. Koshida H. Konaka T. Uchibayashi K. Yokoyama K. Hirano M. Namiki 《Urological research》1998,26(6):377-382
The purpose of this study was to investigate the effect of natural interferon (IFN) on the expression of placental alkaline
phosphatase (PLAP) in a human seminoma xenograft in severe combined immunodeficient mice. Mice were injected intramuscularly
with 3 × 105 U/mouse of IFN, twice a day, for five consecutive days. A significant increase in PLAP level of the xenografts followed IFN
treatment. A radiolabeled anti-PLAP monoclonal antibody (MAb) was intravenously injected on the first day of IFN administration
in order to determine if IFN has the potential to enhance the efficacy of an anti-PLAP MAb in the detection of seminoma. Enhanced
retention of the anti-PLAP MAb was observed at 7 and 11 days after MAb administration. Thus, IFN treatment appears to have
some effect on the efficacy of the anti-PLAP MAb in the detection of seminoma xenografts.
Received: 26 September 1997 / Accepted: 23 April 1998 相似文献
26.
Time-dependent morphological alterations of cold-stored small bowel in Euro-Collins and Ringer's lactate solutions 总被引:2,自引:0,他引:2
Small bowel is one of the organs that can in principle be transplanted. Optimum preservation of the organ is essential for the success of transplantation. The aim of the present study is the investigation of time-related morphological changes of rat small bowel during preservation in hypothermic Euro-Collins (EC) and Ringer's lactate (RL) solution using light microscopy and transmission electron microscopy to evaluate the integrity of intercellular complexes of mucosal epithelium, one of the tissues of the intestine that is most susceptible to ischemia. Small bowels were perfused with either EC, RL solution or physiological saline solution and were placed in the different preservation solutions at 4 degrees C for 0, 3, 6 and 12 h. The results of our study suggest that both preservation solutions are suitable for short-term preservation of the small bowel although RL solution is more effective than EC solution. However, we conclude that further improvement of preservation solutions and/or techniques are needed to perform long-term preservation. 相似文献
27.
甲状腺功能亢进患者骨代谢指标和甲状腺激素水平变化及其临床意义 总被引:1,自引:0,他引:1
为探讨甲状腺功能亢进(甲亢)患者骨代谢指标与甲状腺激素水平的变化, 本文对70例甲亢患者及60名健康对照者采用放射免疫分析法(RIA)测定了Ⅰ型胶原羧基末端肽(ICTP), 全自动微粒子化学发光分析法测定了骨碱性磷酸酶(BAP)及甲状腺激素(T3、T4、FT3、FT4)水平, 同时用二维骨密度仪测定骨密度(BMD).结果表明: 甲亢患者血清BAP、ICTP与甲状腺激素水平均明显高于健康对照组(P均小于0.01), 骨密度(BMD)则显著低于健康对照组(P<0.01).相关分析显示, 甲亢患者血清BAP、ICTP水平与BMD呈明显负相关(r分别为-0.298和-0.276, P<0.05), 与T3呈正相关(r分别为0.452和0.531,P<0.01), 与T4亦呈正相关(r分别为0.419和0.398, P<0.01).提示甲亢患者骨转换增强, 并以骨吸收增加更为显著, 与甲亢时甲状腺激素分泌过多有关. 定量检测血清BAP、ICTP水平对于甲亢代谢性骨病的诊断、病情研究均有重要的临床价值. 相似文献
28.
E. D. Gol'dberg G. V. Karpova E. V. Melik-Gaikazyan G. N. Pakhryaeva 《Bulletin of experimental biology and medicine》1978,85(2):150-151
The content of acid and alkaline phosphatases was studied in the lymphocytes of the peripheral blood, bone marrow, and lymphoid organs (thymus, spleen, lymph node) of intact noninbred rats. The mean percentage of cells containing the enzymes was determined. Their organ and species characteristics are described.Central Research Laboratory and Department of Pathophysiology, Tomsk Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR I. V. Toroptsev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 2, pp. 158–159, February, 1978. 相似文献
29.
Comparative study of pituitary and bacteria-derived human growth hormone by monoclonal antibodies 总被引:1,自引:0,他引:1
We have established hybridoma lines which secrete mouse monoclonal antibodies (Mabs) to human pituitary growth hormone, hGH. Using indirect competitive ELISA and indirect passive hemagglutination inhibition twelve different Mabs were characterized with regard to cross-reactivity with the hGH-related hormones, human chorionic somatomammotropin, hCS, and human prolactin, hPRL. The reactivity of these Mabs with pituitary hGH was compared to that with either bacterially-produced methionyl-hGH or to that of reduced and S-carboxymethylated hGH, which has an altered conformation. None of the Mabs reacted with hPRL. Four did not react with hCS whereas the others showed varying degree of cross-reactivity with hCS. All Mabs reacted more weakly with reduced and S-carboxymethylated hGH than with the native form of the hormone, which was not seen with conventional rabbit antisera to hGH. Thus in the case of hGH the Mabs are superior to conventional antisera in revealing small conformational differences. However the pituitary and bacterially-derived methionyl-hGH were indistinguishable as determined by the 12 Mabs. 相似文献
30.
M. A. Lushchitskii K. K. Zaitseva V. A. Bubnov A. P. Utochkin V. V. Grigor'ev 《Bulletin of experimental biology and medicine》1988,105(4):586-588
Department of Naval and Military Surgery, Research Laboratory of Electron Microscopy and Histochemistry, S. M. Military Medical Academy, Leningrad. (Presented by Academician of the Academy of Medical Sciences of the USSR A. P. Kolesov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 105, No. 4, pp. 486–488, April, 1988. 相似文献