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81.
O. F. M. SELLEVOLD T. M. BERG K. A. REIN O. W. LEVANG O–J. IVERSEN K. BERGH 《Acta anaesthesiologica Scandinavica》1994,38(4):372-379
A prospective randomized study was performed to investigate the effect of surface coating with covalently endpoint–attached heparin (Carmeda Bio Active Surface) and reduced general heparinization on haematological indices and complement C5 activation. Care was taken to optimize the rheological design of the system using centrifugal pump and a closed system without venting or machine suction. Twenty patients scheduled for aortocoronary bypass grafting (EF > 0.5) participated in the study. Ten patients were randomized to be treated with heparin–coated equipment (CBAS) and reduced i.v. heparin (1.5 mg kg-1) while 10 patients treated with identical but noncoated equipment and full heparinization (3 mg–kg-1) served in a Control group. A vacuum suction was used to collect the blood from the operating field and it was autotransfused at weaning from extracorporeal circulation (ECC). Blood samples were obtained from the venous (precircuit) and arterial (postcircuit) side. We used a new and very specific method for detection of C5a based on monoclonal antibodies. The concentration of C5a was low in both groups during the operation but a significant increase was seen on days 1 and 2. In the Control group there was an increase from 10.2 ngml-1±1.2 to 27.5 ng ml-1 ± 4.8 on day 2 and in the CBAS group from 10.7 ng ml-1 ± 1.2 to 35.6 ng ml-1 ± 11.6 on day 2 (NS between groups). The granulocytes and total leukocyte count increased at the end of ECC and was maintained at the elevated level throughout the study period. The amount of free haemoglobin was high in the autotransfused blood in both groups. The present results confirm the feasibility of reducing general heparin when using heparin–coated systems but the study does not support the superiority of such coating with regard to biocompatibility in short procedures with a Theologically optimized circuit. The potential benefit from reduced heparin and protamine has not been fully evaluated. 相似文献
82.
α-L-岩藻糖苷酶测定的临床应用 总被引:1,自引:0,他引:1
研究结果表明AFU测定对肝癌的诊断具有较高的敏感性和特异性,其价值优于AFP,两项指标联合检测可提高阳性检出率。动态监测有利于肝癌的早期诊断、鉴别诊断,并可作为转移、复发的指标,也可用于白血病及卵巢癌的诊断。 相似文献
83.
本文采用俯卧拍背法缓解胆绞痛41例,其中23例经此法治疗后疼痛立即消失(56.1%);15例明显缓解(36.6%);3例缓解不明显(7.3%)。具有操作简便、安全,易被患者接受,值得推广。 相似文献
84.
85.
Wataru Kimura 《Journal of hepato-biliary-pancreatic sciences》2003,10(2):156-162
The differences and similarities between intraductal papillary mucinous tumor (IPMT) and mucinous cystadenoma or carcinoma (mucinous cystic tumor; MCT) of the pancreas have been noted. The similarities include: (1) both tumors originate from pancreatic duct cells, (2) massive mucin production is found in both tumors, and (3) papillary projection is a common histological characteristic. However, there are also many differences. IPMT is most frequently found in men in their sixties, and originates in the head of the pancreas, with 62% (123/199) of tumors reported to be found in the head of the pancreas. This tumor sometimes spreads throughout the entire pancreas. The tumor itself basically is of the dilated pancreatic duct type, and the prognosis is generally good. In contrast, MCT frequently develops in women in their forties. This tumor is usually large, round, and almost totally encapsulated by fibrous tissue, with no communication with the pancreatic duct. The tumor histologically has an ovarian-like stroma. It most often develops in the body or tail of the pancreas. Invasion is often present and the operative prognosis is not good. IPMT resembles the shape of a bunch of grapes and MCT resembles that of an orange. From the differences between these two types of tumors, they are classified into different categories. With regard to therapeutic strategies for MCT, the tumor should be resected with lymph node dissection immediately when it is detected. In contrast, some patients with branch-type IPMT can be followed without surgical procedures. Because IPMT shows good prognosis and little tendency for infiltration, some kinds of organ-preserving procedures would be possible for some patients with this tumor. Such organ-preserving procedures are: duodenum-preserving pancreas head resection, spleen-preserving distal pancreatectomy with conservation of the splenic artery and vein, and so on. 相似文献
86.
87.
S E Irwin G Y Kwei G R Blackburn R Thurman F C Kauffman 《Environmental and molecular mutagenesis》1992,19(3):253-258
Comparison of the mutagenicity of nine isomeric benzo(a)pyrenyl [B(a)P] phenols conjugated with either sulfate or glucuronide was carried out using strain Salmonella typhimurium TA98. Of the nine conjugates tested, only B(a)P-1-sulfate was mutagenic. Accordingly, the mutagenicity of B(a)P-1-sulfate was compared with that of B(a)P and 1-hydroxybenzo(a)pyrene [B(a)P-1-OH] in the presence and absence of rat lung S9 and Aroclor-induced liver S9 with and without an NADPH-generating system. B(a)P-1-sulfate was slightly mutagenic, whereas B(a)P and the 1-hydroxy derivative were nonmutagenic when S9 fractions and NADPH were omitted. Addition of induced liver S9 with NADPH caused mutagenicity with B(a) -1-OH greater than B(a)P greater than B(a)P-1-sulfate. B(a)P-1-sulfate was the only mutagenic species when lung S9 was added. This mutagenicity did not require NADPH. Sodium sulfite, an inhibitor of arylsulfatase, decreased the mutagenicity of B(a)P-1-sulfate. These data suggest that a unique mutagenic species is generated from B(a)P-1-sulfate via arylsulfatase in rat lung. 相似文献
88.
Atsutoshi Ina Ken-Ichiro Hayashi Hiroshi Nozaki Yuto Kamei 《International journal of developmental neuroscience》2007,25(1):63-68
We identified and characterized a neurodifferentiation compound from the marine brown alga Sargassum fulvellum collected from the Japanese coastline. Several instrumental analyses revealed the compound to be pheophytin a. Pheophytin a did not itself promote neurite outgrowth of PC12 cells. However, when PC12 cells were treated with a low concentration of pheophytin a (3.9 microg/ml) in the presence of a low level of nerve growth factor (10 ng/ml), the compound produced neurite outgrowth similar to that produced by a high level of nerve growth factor (50 ng/ml). Pheophytin a also enhanced signal transduction in the mitogen-activated protein kinase signaling pathway, which is also induced by nerve growth factor. The effect of pheophytin a on neurite outgrowth of PC12 cells was completely blocked by U0126, a representative mitogen-activated protein kinase kinase inhibitor. These results suggest that pheophytin a enhances the neurodifferentiation of PC12 cells in the presence of a low level of nerve growth factor and that this effect is mediated by activation of a mitogen-activated protein kinase signaling pathway. 相似文献
89.
目的:探讨Gd-DTPA动态增强MRI评价心肌微血管损伤的可行性。方法:制作急性犬心肌梗死动物模型,在活体上用放射微球^99Tc—MAA测量心肌血流量,0.5%伊文蓝染色区分缺血心肌;心脏离体后用3%TTC染色区分梗死心肌,SP免疫组化染色观察心肌微血管并计算微血管体积分数。犬离体心脏左冠状动脉插管后作MRI平扫及Gd—DTPA动态增强扫描,测量正常、缺血和梗死心肌的信号强度,绘制时间-信号强度曲线。结果:在T1WI上,心肌信号强度无明显差异;在T2WI上,病变心肌信号强度较正常增高;Gd-DTPA灌注动态增强扫描,正常心肌时间-信号强度曲线呈下降形,危险心肌呈上升形,梗死心肌呈平直形,灌注晚期病变区呈明显环状强化。正常、危险和梗死心肌血流量、微血管体密度差异显著。结论:急性心肌梗死后心肌间质水肿、心肌含水量增加致T2WI信号增高。Gd-DTPA动态增强时间-信号强度曲线上升的斜率及峰值可以反映心肌微血管损伤及组织水肿的程度。 相似文献
90.
100mg香烟烟油,多氯联苯诱导大鼠肝S_9组分中芳香烃羟化酶代谢B[a]P为3-OH-B[a]P的活性分别升高约40,20倍,而代谢B[a] P生成6-OXY-B [a]P自由基产物却仅由多氯联苯诱导的S_9组分作用中才被观察到。 相似文献