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71.
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   
72.
α-L-岩藻糖苷酶测定的临床应用   总被引:1,自引:0,他引:1  
侯振江  张宗英 《华夏医学》2003,16(5):742-743
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   
73.
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   
74.
本文探讨了ASA剂量与药效的关系及血ASA、SA药物浓度监测的临床意义,结果表明:(1)ASA剂量与6-keto-PGF_(1α)抑制率呈正相关(P<0.01),而与TXB_2及PAgR抑制率无相关性(P>0.1);(2)本文采用HPLC内标法同时测定血ASA和SA浓度,结果准确,方法简便;(3)当口服小剂量ASA防治CI时,监测血ASA和SA以调整ASA用药剂量的临床价值并非十分重要。  相似文献   
75.
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   
76.
77.
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   
78.
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   
79.
无张力阴道吊带术治疗女性压力性尿失禁   总被引:13,自引:1,他引:12  
目的:探讨无张力阴道吊带术(TVT)治疗女性压力性尿失禁的初步疗效和手术安全性。方法:对20例经过临床和尿动力学检查诊断为压力性或混合性尿失禁的女性患者进行TVT手术治疗,并对手术效果和并发症进行初步的随访研究。结果:平均手术时间40min(25—100min),平均术后住院3.2d(1—28d)。18例单纯性压力性尿失禁患者16例治愈,治愈率为88.89%(16/18),另2例显效(11.1%)。2例混合性尿失禁患者中1例显效,另1例无效。术后发生尿潴留3例,2例作松解术,1例延长导尿管留置时间后缓解。发生局部血肿1例经保守治疗后康复。结论:TVT手术是一种治疗压力性尿失禁的安全有效的方法,具有手术简单、创伤小、并发症少、患者康复快等优点。  相似文献   
80.
无张力阴道吊带术治疗女性压力性尿失禁(附20例报告)   总被引:3,自引:2,他引:1  
目的 评价无张力阴道吊带术(tension-free vaginal tape,TVT)治疗女性压力性尿失禁的疗效。方法 总结采用TVT术治疗女性压力性尿失禁20例的临床资料。结果 平均手术时间26.5min。拔除尿管后,19例病人控尿满意,1例仍有轻微尿失禁。术后平均随访12(3-24)个月,20例病人均无尿失禁。合并症有1例膀胱穿孔,1例术后轻度排尿不畅,2例尿频尿急。结论 TVT术操作简便快捷,创伤小,合并症少,术后康复快,是一种治疗女性压力性尿失禁的理想方法。  相似文献   
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