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51.
目的 :研究癌基因 (ras,c myc)及抗癌基因 (p5 3)蛋白在喉癌及癌旁不同距离处的复合表达及意义。方法 :应用LSAB微波免疫组织化学法 ,检测了ras、c myc及p5 3在 30例喉癌组织、边缘区、癌旁 0 .5cm ,1.0cm ,1.5cm ,2 .0cm处粘膜组织和 4例正常喉粘膜组织中的复合表达情况。结果 :① 2种以上基因蛋白产物同时表达阳性者在喉癌组织中为 2 8例 (93.3 % ) ,其中ras +c myc +p5 3为 17例 (5 6 .7% ) ,癌旁组织中也存在着不同程度的复合表达 ,而正常喉粘膜组织中无一例复合表达 ;②复合表达阳性率依正常粘膜组织→癌旁 2 .0cm→ 1.5cm→ 1.0cm→0 .5cm→边缘区→癌组织递增 ,且癌旁 1.0cm处与 0 .5cm范围内的表达存在显著差异 (P <0 .0 5 ) ;③ 3种癌基因产物的复合表达与喉癌的部位 ,分化程度 ,临床分期无关 (P >0 .0 5 )。结论 :喉癌及癌旁组织中存在着 3种癌基因的复合表达 ,其在喉癌的发生中有协同作用 ;距癌 0 .5cm以内的癌旁组织应视为危险性病变。 相似文献
52.
探讨利用从小鼠腹水中分离获得的单克隆抗体杂交瘤细胞,大量制备小鼠单克隆抗体腹水的方法收集已接种单克隆抗体杂交瘤细胞的小鼠腹水,用淋巴细胞分离液离心分离腹水中的杂交瘤细胞;再将此分离出的杂交瘤细胞,注入其他小鼠腹腔又制得腹水。每只小鼠分离得到的杂交瘤细胞可供5只小鼠腹腔注射,平均每只小鼠产腹水3.97ml。此法可规模制备大量高效价的单克隆抗体腹水。 相似文献
53.
目的:研究酮咯酸氨丁三醇滴眼液(KTOS)对家兔化学性及外伤性眼部炎症的作用。方法:用巴豆油致炎液经角膜注入眼前房法制备兔眼部急性化学炎症模型;用重物击打眼睑法制备兔眼部急性外伤性炎症模型。将致炎后的动物随机分组给药,并参照眼部炎症评判标准进行评分统计。结果:各KTOS剂量组对外伤性和化学性眼部炎症作用的评分均低于生理盐水组;小剂量KTOS虽有作用,但无统计学意义(P>0.05),而中、大剂量KTOS均有明显改善外伤性和化学性眼部炎症的作用(P<0.05,P<0.01);其中对化学性眼部炎症的作用与地塞米松作用相似,对外伤性眼部炎症的作用优于地塞米松。结论:KTOS对外伤性和化学性眼部炎症均有明显的抗炎作用,对外伤性眼部炎症的抗炎作用更强。 相似文献
54.
55.
John R. Steele Sean P. Ryan William A. Jiranek Samuel S. Wellman Michael P. Bolognesi Thorsten M. Seyler 《The Journal of arthroplasty》2021,36(5):1729-1733
BackgroundRevision total knee arthroplasty (TKA) involves varying levels of case complexity and costs depending on the following: (1) number of components revised, (2) duration of operating room time, and (3) length of hospital stay. However, the cost associated with different types of aseptic TKA revisions, based on number and type of components revised, is not well described. We sought to determine differences in cost associated with different revision types, and to correlate this with average national hospital and surgeon reimbursement based on current Centers for Medicare and Medicaid Services data.MethodsThis is a retrospective review of aseptic revision TKAs performed at a single tertiary referral center from 2015 to 2018. Patient demographic data, operating room time, and direct surgery and total hospital costs obtained from an internal accounting database (Enterprise Performance Systems, Inc) were collected. Patients were stratified by the components revised (polyethylene liner only, tibia only, femur only, or both femur and tibia). We hypothesized that direct surgery and total hospital costs would increase as case complexity increased from poly exchange to single-component revisions and both-component revisions.ResultsIn total, 106 patients were included (19 poly exchanges, 10 tibia-only revisions, 13 femur-only revisions, and 64 both-component revisions). Operating room time was significantly lower for poly exchange than all other groups (P < .001). Direct surgery and total hospital costs were significantly lower for poly exchange than all other groups (P < .001), and were significantly lower for tibia-only and femur-only revisions compared to both-component revisions (P < .001). Average national surgeon reimbursement by Medicare decreased as a percentage of direct surgery cost as case complexity increased from poly exchange to tibia-only, femur-only, and both-component revisions. Total hospital cost per average Diagnosis Related Group weight was lowest for single-component revisions and highest for both-component revision.ConclusionThere are significant differences in cost associated with aseptic TKA revisions based on number and type of components revised. These differences may not be accurately reflected in reimbursement, and often represent a burden to those who treat complex revisions. 相似文献
56.
Continued advances in the understanding and management of congenital heart disease (CHD) mean that over 90% of children born with CHD now survive to adulthood. This in turn results in greater numbers of adult patients presenting for medical and surgical care at non-specialist centres. A simple classification of adult congenital heart disease (ACHD) according to complexity can help clinicians to understand the implications of the specific cardiac anomaly encountered. Issues relating to the conduct of anaesthesia in ACHD patient include careful attention to euvolaemia, the preservation of sinus rhythm and cardiac output, and in complex patients, manipulating the balance between systemic and pulmonary blood flows. Additionally, effective antibiotic prophylaxis and the prevention of either excessive bleeding or thromboembolism are vitally important. It should not be forgotten that although many patients with simple or repaired cardiac lesions may be very well managed in a non-specialist unit, those with Eisenmenger’s syndrome or severe pulmonary hypertension have an extremely high risk of death in the perioperative period, and in all but life-threatening situations should always be managed within specialist centres. 相似文献
57.
《Anaesthesia and Intensive Care Medicine》2021,22(11):729-737
The clotting cascade is a complex process and is an important survival mechanism. Major haemorrhage and thromboembolic events remain major causes of increased morbidity and mortality. Drugs affecting coagulation have primarily been utilized to treat or reduce the risk of thromboembolic events. However, the recent progress in the management of major trauma and treating coagulopathy has resulted in further research and development of drugs that improve clotting function. Knowledge of drugs used for both clinical circumstances is now required when working in anaesthesia or intensive care. 相似文献
58.
Role for macrophage migration inhibitory factor in acute respiratory distress syndrome 总被引:18,自引:0,他引:18
The critical role of macrophage migration inhibitory factor (MIF) in mediating inflammatory lung injury in acute respiratory distress syndrome (ARDS) has been raised recently. The present study has identified enhanced MIF protein expression in alveolar capillary endothelium and infiltrating macrophages in lung tissues from ARDS patients. The possibility that MIF up-regulates its synthesis in an autocrine fashion in ARDS was tested using cultured endothelial cells stimulated with MIF and a murine model of lipopolysaccharide (LPS)-induced acute lung injury. MIF induced significant MIF and tumour necrosis factor (TNF)-alpha synthesis in cultured endothelial cells and the effect was blocked by neutralizing anti-MIF antibody. A similar blocking effect was observed when MIF-stimulated endothelial cells were pretreated with neutralizing anti-TNF-alpha antibody or glucocorticoid, supporting the notion that MIF induced TNF-alpha production via an amplifying pro-inflammatory loop. Treatment with anti-MIF or glucocorticoid effectively attenuated pulmonary pathology and the synthesis of MIF or TNF-alpha in mice with LPS-induced acute lung injury. Mildly augmented expression of aquaporin 1 (AQP1) was also detected in alveolar capillary endothelium in ARDS. In vitro studies revealed that both MIF and TNF-alpha induced a small increase of AQP1 synthesis in cultured endothelial cells. These findings suggest that MIF plays a crucial pathological role leading to alveolar inflammation in ARDS. Anti-MIF and early glucocorticoid therapy may represent a novel therapeutic approach for reducing alveolar inflammation in ARDS. 相似文献
59.
凝血酶对人重组内皮细胞衍生IL—8融合蛋白转换作用 总被引:3,自引:0,他引:3
本文报道利用基因工程技术在大肠杆菌中表达出入内皮细胞衍生IL-8(EDhIL-8)与细菌蛋白lacZ 的融合蛋白lac-hIL-8和lac-T-hIL-8,后者含有一个人工合成凝血酶切点。EDhIL-8上含有一个凝血酶切点,凝血酶可以将lac-hIL-8及以前表达的MS2-hIL-8水解为有生物活性的天然IL-8,而对含有两个凝血酶切点的lac-T-hIL-8无水解作用。这些结果提示凝血酶的功能不仅依赖于所识别的氨基酸,而且依赖于这些氨基酸形成的构象。 相似文献
60.
目的:研究7-取代-2-取代-6,8二氟-1,4-二氢-4-氧-3-喹啉羧酸的合成,体外抗菌活性及其构效关系。方法:通过缩合,Gould-Jacobs环合,亲核取代得到关键中间体,然后通过反应制得目标化合物,选用临床常见致病菌的标准菌株进行体外抗菌活性测定。结果:设计合成26个化合物,其中20个化合物为首次报道,抗菌活性实验以氟罗沙星为对照Ⅲi,Ⅲj和苯环上无取代的化合物Ⅲb1,Ⅲb2的活性比氟罗沙星稍好,特别是化合物Ⅲb2的活性优于氟罗沙星。结论:合成的26个化合物中有一些化合物显示了较好的抗菌活性。其中化合物Ⅲb2的活性优于氟罗沙星,该类化合物值刘进一步研究。 相似文献