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1.
Forest biomass (FB) is widely used overseas as an industrial energy source, particularly in Europe, but is currently little used in Australia. Typical attributes of FB disadvantage it as a fuel relative to traditional energy sources: high moisture content, low bulk density, spatial and temporal dispersion, low value and low energy content. As such, minimising FB delivered costs will be critical to further development of Australian forest biomass supply chains (FBSC).

The paper reviews published international and Australian research into the key FBSC elements (biomass source, primary transport, storage, secondary transport and processing) focussing on areas where Australian FBSCs could potentially apply the research to reduce costs and where additional Australian research is required. Logging residue (LR) was identified as the FB resource in Australia with the greatest potential for use as biofuel. Rapid infield drying of LR in Australian studies suggests that infield drying could be used to reduce secondary transport costs, which can be a significant part of the delivered FB costs. However, further development of Australian FBSC models supported by research into primary and secondary transport costs, drying and chipper performance will be required to identify trade-offs between potential FBSC costs and benefits and to facilitate forest managers’ decision-making processes regarding the establishment and running of FBSCs.  相似文献   
2.
BACKGROUND: The purpose of this study was to search for a more effective transfusion-monitoring system than the existing system of retrospective peer review. STUDY DESIGN AND METHODS: This research used a study-control, preintervention and postintervention design, to evaluate the effectiveness of a prospective physician self-audit transfusion-monitoring system that functioned without the direct involvement of transfusion service physicians. This research also evaluated the effectiveness of issuing to physicians a memo with transfusion guidelines. Three process indicators were used to assess physician behavior at various stages of the blood-ordering process: 1) the number of crossmatches ordered per admission, 2) the transfusion-to- crossmatch ratio, and 3) the number of blood units returned to the laboratory after physician self-auditing. The study used two outcome indicators to reflect overall blood utilization: 1) the percentage of patients who received red cell transfusions and 2) the number of blood units transfused per recipient each month. RESULTS: The prospective physician self-audit system implemented at the study hospital did not reverse physician transfusion decisions, and the process of issuing to physicians a memo with transfusion guidelines at the control hospital failed to reduce blood usage. However, a transient reduction in blood utilization was observed at the study hospital. CONCLUSION: The reduction was hypothesized to be due to a Hawthorne effect, in which observed behavior is affected by the subject's awareness of the research study.  相似文献   
3.
Reported here are studies of Fanconi anemia fetal cells that led to the first use of umbilical cord blood for hematopoietic reconstitution in a clinical trial. Prenatal diagnosis and HLA typing were performed in fetuses at risk for Fanconi anemia (FA) to identify, prior to birth, those that were unaffected with the syndrome and were HLA-identical to affected siblings. Umbilical cord blood was harvested at the delivery of these infants; assays of progenitor cells indicated the presence of colony-forming units-granulocyte-macrophage (CFU-GM) in numbers similar to those of bone marrow CFU-GM that are associated with successful engraftment in HLA-matched allogeneic bone marrow transplantation. The possibility that umbilical cord blood from a single individual can be used as an alternative to bone marrow for hematopoietic reconstitution has now been demonstrated by the successful engraftment of two patients with FA. Progenitor cell assays of umbilical cord blood collected at the birth of a child affected with FA, who had been misdiagnosed on the basis of chorionic villus sampling (CVS) studies, indicated a profound deficiency in colony formation, consistent with previously reported abnormalities in the growth of FA cells in vitro. These results suggest that the hematopoietic disorder in FA is related to an underlying problem with cell proliferation.  相似文献   
4.
目的:建立恢复种植体周围骨缺损的自体骨碎末骨移植材料的实验模型。方法:实验于2005-08/2006-04在大连医科大学动物实验基地(辽宁省重点实验室)完成。①实验材料:健康杂交家犬5只,体质量15~20kg。Bio-Oss骨移植材料为引导骨/组织再生多孔骨无机材料,白色颗粒状,颗粒大小1.0~2.0mm。②实验方法:拔除家犬下颌第1,2,3前臼齿,3个月后行种植术。预备种植体窝,每只犬左右两侧各预备4个,共40个。在每个种植窝内,各植入种植体钛钉1枚,共40枚。用种植转孔时收集的自体骨碎末、Bio-Oss骨移植材料及两者1∶1混合骨碎末恢复种植体颊侧单壁人为骨缺损,以未植骨作空白对照。③实验评估:第9周时观察各组骨量的恢复情况、X线片观察牙槽骨高度、骨小梁致密度及骨整合情况,亚甲基蓝-碱性品红法观察组织学变化。结果:5只家犬钛钉均无脱落,均纳入结果分析。①一般情况:9周时,创口愈合均良好,钛钉稳定,总存留率为100%。骨缺损处已有不同程度恢复,与正常骨组织无明显差别。②9周时各组骨缺损量的测量结果:植入自体骨碎末、Bio-Oss骨移植材料、混合骨碎末及空白对照组的平均骨缺损量分别为1.8125、1.6975、1.5025、2.6375mm。植入混合骨碎末的平均骨缺损量最小,说明恢复最佳。③X线观察骨量的恢复情况:40颗钛钉外周均与骨组织紧密接触,愈合良好。不同组间未见明显骨质密度区别。④组织学观察骨量的恢复情况:低倍镜下见所有钛钉均被周围淡红色的致密骨组织紧密包绕,种植体与骨组织间无蓝色的软组织,产生了直接骨结合界面。结论:应用家犬建立自体骨碎末移植材料恢复种植体周围骨缺损的实验模型效果理想。  相似文献   
5.
SUMMARY Eighty-eight women with a history of recurrent urinary tractinfection (at least four attacks in the preceding 12 months)were randomized to take either norfloxacin 200 mg at night (45patients) or macrocrystalline nitrofurantoin 100 mg at night(43 patients) for 12 months. A decrease in the number of symptomaticattacks while taking this prophylaxis was observed in 94 percent of the patients and this improvement was maintained duringthe 6 months following the end of prophylaxis in 69 per cent.The mean interval between symptomatic episodes while takingprophylaxis was 7.2-fold and 6.9-fold greater, respectively,than in the 12 months before starting prophylaxis. There wereonly nine breakthrough infections during 74 patient-years ofprophylaxis, four in patients taking norfloxacin (two enterococci,one Staphylococcus epidermidis, one Escherichia coli), and fivein those taking macrocrystalline nitrofurantoin (four E. coli,one Klebsiella pneumoniae). Adverse events caused four patientstaking norfloxacin (8 per cent) and seven taking macrocrystallinenitrofurantoin (14 per cent) to stop prophylaxis. Norfloxacinhad a marked suppressive effect on the coliform part of thefaecal flora, with no emergence of resistance. Thus, norfloxacinappears to be an excellent alternative agent to macrocrystallinenitrofurantoin for the prevention of recurrent urinary infections.  相似文献   
6.
7.
To determine whether reactive oxygen molecules could directly and reversibly increase the transfer of albumin across an endothelial barrier, we measured albumin transfer across monolayers of endothelium cultured on micropore filters before and after exposure to xanthine and xanthine oxidase. Xanthine and xanthine oxidase increased endothelial albumin transfer in a dose-dependent fashion. Parallel phase contrast and fluorescence microscopy demonstrated retraction of adjacent cells from one another and disruption of the actin filaments. The oxidant- induced increases in albumin transfer and changes in cell shape were reversed by removing xanthine oxidase and then incubating the monolayers for 3 1/2 hours in tissue culture media enriched with fetal bovine serum. However, incubation in tissue culture media without serum resulted in progressive injury and cell death. Hence, the brief exposure to oxidants initiated a progressive injury process that was reversed by incubation in serum. Because intracellular and extracellular calcium are important determinants of cell shape, and because some oxidized membrane lipids act as calcium ionophores, we asked whether oxidants altered endothelial calcium homeostasis. Xanthine-xanthine oxidase increased release of 45Ca++ from preloaded cells. The calcium antagonist lanthanum chloride prevented xanthine- xanthine oxidase increases in endothelial albumin transfer and prevented the changes in cell shape; chelation of extracellular calcium inhibited lysis of endothelium by xanthine-xanthine oxidase; and the calcium ionophore A23187 increased endothelial albumin transfer and mimicked the oxidant-induced changes in cell shape. Lanthanum chloride inhibited these effects of A23187. These data suggest that oxygen radicals can reversibly increase endothelial permeability to macromolecules, that this is associated with reversible changes in endothelial cell shape and actin filaments, and that the changes in cell shape are related to oxidant-induced changes in endothelial calcium homeostasis.  相似文献   
8.
Andreesen  R; Osterholz  J; Lohr  GW; Bross  KJ 《Blood》1984,63(6):1299-1302
A Hodgkin cell-specific antigen detected by the monoclonal antibody Ki- 1 was found on T helper lymphocytes after activation by autologous and allogeneic stimulator cells. About 50% of lymphoblasts generated by auto- and alloactivation reacted with the antibody. In contrast, only less than 6% of lymphoblasts stimulated with Con-A, phytohemagglutinin (PHA), or protein A, and none of lymphoblasts activated by oxidative mitogenesis, expressed this antigen. Among several permanent cell lines tested, the K562, MOLT-4, HL-60, and EBV transformed B lymphoblastoid cells reacted with the Ki-1 antibody. The results may indicate possible relationships between the autoreactive subset of T lymphocytes and the pathogenesis of Hodgkin's disease.  相似文献   
9.
10.
Since February, 1980 nearly 200 automatic cardioverter - defibrillators have been implanted in patients with malignant ventricular arrhythmias. The currently-employed device weighs 298 grams and occupies a volume of 162 cm3. There are two defibrillation electrodes which also serve as sensors: one, an intravascular catheter placed in the superior vena cava at the level of the right atrium; the other, a flexible rectangular patch placed extrapericardially over the apex of the heart. Additionally, there is a bipolar right ventricular electrode for rate counting and R-wave synchronization which will eventually be used for pacing as well. The unit is powered by lithium batteries with a projected monitoring life of three years, or the capability of discharging approximately 100 times. The arrhythmia detector activates the cardioverter -defibrillator about 15 to 20 seconds after diagnosing a "treatable" arrhythmia, identified on the basis of a striking absence of isoelectric potential segments characteristic of ventricular fibrillation and many ventricular tachycardias. The diagnosis also requires fulfillment of individually-programmed heart rate criteria. If the initial discharge of 25 joules is ineffective, the device will recycle as many as three times with a final pulse of up to 42 joules. Of the twelve nonsurvivors among the initial 52 implantees who underwent implantation through September, 1982, only four deaths were unwitnessed and considered to be sudden and arrhythmic; the other eight deaths were due to heart failure or unrelated causes. Thus, from a predicted mortality of 48% in the same group of patients if the automatic defibrillator had not been implanted, the "sudden death" mortality was reduced to 8.5%.  相似文献   
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