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51.
S K Oh  D L Very  J Walker  S Raam  S T Ju 《Cancer research》1987,47(19):5120-5126
In spite of the numerous reports indicating the presence of humoral immunosuppressive factors in cancer patients, only a few of these factors have been biochemically identified. Furthermore, their role as effective immunosuppressors in vivo remains to be established. Our laboratory has attempted to isolate and identify the major immunosuppressive factor in the malignant effusions derived from ovarian and lung cancer patients. We have previously demonstrated that the Mr 52,000 immunosuppressive factor isolated from the ascites fluid of an ovarian cancer patient inhibited T-dependent immune responses in vivo and in vitro including the inhibition of E-rosetting. Thus, this immunosuppressive factor was named "suppressive E-receptor" (SER). Our current study demonstrates that this SER factor purified from malignant effusions derived from ovarian, lung, or head and neck cancer patients had a common component which dissociated equally into Mr 38,000-42,000 and 17,000-19,000 moieties on sodium dodecyl sulfate-polyacrylamide gel electrophoresis under vigorous reducing conditions. Electroelution of these two components followed by a limited amino acid sequence determination revealed these two components to have N-terminal amino acid sequences identical to the beta and alpha 2 subunits of normal adult haptoglobin. Immunoelectrophoresis of SER using a polyclonal antiserum to neonatal cord blood demonstrated that SER, unlike normal haptoglobin, has slower electrophoretic mobility than the normal adult haptoglobin. Western blotting analysis of SER separated on sodium dodecyl sulfate-polyacrylamide gel electrophoresis under denaturing conditions failed to recognize a monoclonal antibody directed specifically to SER. However, this monoclonal antibody exclusively reacted with the SER separated by an analytical polyacrylamide gel electrophoresis gel under nondenaturing conditions while normal adult haptoglobins or purified but denatured haptoglobin obtained from the same malignant fluid as SER all failed to react with this antibody. Thus, SER appears to bear an additional epitope(s) that is absent in normal adult haptoglobin. Since the SER as well as the neonatal haptoglobin have at least 100 to 1000-fold more potent immunosuppressive activity than the normal adult haptoglobin, this additional epitope(s) present in SER may be responsible for the potent immunosuppressive property of SER.  相似文献   
52.
53.
目的:认识多发伤中骨折的主要特点,探讨内固定在救治中的意义。方法:回顾1994-08~1999-08间手术救治多发伤66例,对其161处骨折中的98处进行了“仿AO技术”有关方法内固定。结果:骨折均满意愈合;涉及骨折关节51个,功能恢复满意率为96.08%。结论:在多发伤中,骨折、合并伤与并发症远较“一般骨折”复杂、严重;有效固定骨折是一种重要的救命措施;内固定手术应争取在伤后24h进行,但如受条件制约,伤后1-3wk内手术也可获得满意效果;仿AO技术中的某些方法,如拉力螺钉、张力带钢丝及自动加压钢板等,用于内固定可使骨折获得卓有成效的稳定性。  相似文献   
54.
Mortality and morbidity of children received veno‐arterial extracorporeal membrane oxygenation (VA‐ECMO) support after cardiac surgery remain high despite remarkable advances in medical management and devices. The purpose of this study was to describe outcomes and risk factors of applying VA‐ECMO in the surgical pediatric population. We retrospectively analyzed 85 consecutive pediatric patients (aged <18 years) who received postcardiotomy VA‐ECMO from January 2010 to December 2018. Median (IQR) age at ECMO implantation in this cohort was 12.7 (6.4, 43.2) months, median weight was 8.5 (6.0, 12.8) kg, mean ECMO duration was 143.2 ± 81.6 hours and mean hospital length of stay was 48.4 ± 32.4 days. Seventy‐five patients (88.2%) were indicated for postcardiotomy cardiogenic shock. The successful ECMO weaning rate was 70.6% and in‐hospital mortality was 52.9%. The most common diagnosis was transposition of great arteries (n = 18, 21.2%), while acute kidney injury occurred most often (n = 64, 75.3%). Multivariate logistic regression analysis showed that thrombocytopenia, hemolysis, and nosocomial infection were positively correlated with in‐hospital mortality. Multivariate Cox proportional hazard regression analysis presented that thrombocytopenia significantly increased the 180‐day mortality in patients with successful weaning. Therefore, multiple factors had adverse effects on prognosis. Patient selection and procedures from ECMO implantation to weaning need to be closely monitored and performed in a timely manner to improve outcome.  相似文献   
55.
BackgroundPartial nephrectomy or angioembolisation is commonly used for sporadic renal angiomyolipomas (RAMLs) with high RENAL scores, but there is a risk of reduced renal function, postoperative complications, and recurrence.ObjectiveTo describe a new technique for off-clamp laparoscopic evacuation of sporadic RAMLs with high RENAL scores that promotes maximal renal function maintenance and low postoperative complication and lesion recurrence rates.Design, setting, and participantsA retrospective cohort of patients undergoing off-clamp laparoscopic evacuation for sporadic RAMLs with RENAL scores ≥9 from January 2013 to June 2018 was included.Surgical procedureWe highlighted the curettage, suction, packing, and binding (CSPB) technique, a new off-clamp retroperitoneoscopic evacuation technique for sporadic RAMLs.MeasurementsDemographics, preoperative, intraoperative, and postoperative outcomes were assessed.Results and limitationsA total of 141 cases were included. The median (interquartile range [IQR]) tumour size was 7 (6.2–8.2) cm. The median (IQR) RENAL score was 10 (9–11). The median (IQR) operative time was 80 (65–125) min, with a median (IQR) estimated blood loss of 130 (90–362.5) ml. Conversion to neither open surgery nor standard laparoscopy occurred. The warm ischaemia time was zero for all cases. Postoperatively, 13 minor complications (Clavien grade 1) were recorded. No blood transfusions were reported. The glomerular filtration rate did not change significantly from preoperative period to 12-mo follow-up. Recurrence did not occur at the median follow-up period of 48 (36–60) mo. The retrospective design and lack of a control group are limitations of this study.ConclusionsOff-clamp retroperitoneoscopic tumour evacuation using the CSPB technique is feasible, safe, and effective for treating complex sporadic RAMLs.Patient summaryWe report a curettage, suction, packing, and binding technique for off-clamp retroperitoneoscopic evacuation of sporadic renal angiomyolipomas that leads to complete lesion clearance, excellent renal function preservation, and minimal perioperative complications.  相似文献   
56.
胰腺损伤发病率低,但病死率及并发症发生率高,容易出现不良预后。早期诊断有助于胰腺损伤患者及时得到准确有效的治疗,从而改善预后。本文从目前国内外的研究现状出发,胰腺损伤临床表现及实验室检查缺乏特异性,并归纳综述了不同检查方式包括超声、CT、MRCP、ERCP、手术等在胰腺损伤早期诊断、损伤分级、早期治疗、疗效判断、并发症检测等阶段的价值。通过探究多种诊疗方式及新的诊疗理念,结合本中心的诊疗经验,得出一种有效的诊疗模式,以供参考。  相似文献   
57.
Radiation-induced breast angiosarcoma, or secondary angiosarcoma (SAS), is a rare entity with a high risk of metastatic recurrence. Herein, we describe the use of intraoperative fluorescence-based skin angiography to guide surgical resection following a novel immunotherapy-based regimen for SAS resulting in a complete pathological response.  相似文献   
58.
BackgroudOutcomes of traditional treatment for osteonecrosis of the femoral head (ONFH) are not always satisfactory. Hence, cell-supplementation therapy has been attempted to facilitate necrotic-tissue regeneration. Adipose-derived mesenchymal stem cell (ADMSC) transplantation is potentially advantageous over bone marrow-derived MSC implantation, but its outcomes for ONFH remain unclear. The aim of this study was to determine 2-year radiological and clinical outcomes of culture-expanded autologous ADMSC implantation for ONFH.MethodsEighteen hips with necrotic lesions involving ≥ 30% of the femoral head were included. ADMSCs were harvested by liposuction and culture expanded for 3 passages over 3 weeks. With a 6-mm single drilling, ADMSCs were implanted into the necrotic zone. All patients underwent magnetic resonance imaging (MRI), single-photon emission computed tomography/computed tomography (SPECT/CT) at screening and 6 months, 12 months, and 24 months postoperatively. The primary outcome was the change in the size of necrotic area on MRI. Secondary outcomes were changes in clinical scores and radioisotope uptake on SPECT/CT. Conversion total hip arthroplasty (THA) was defined as the endpoint.ResultsPreoperatively, the necrotic lesion extent was 63.0% (38.4%–96.7%) of the femoral head. The mean Harris hip score was 89.2, the University of California at Los Angeles (UCLA) score was 5.6, and Western Ontario and McMaster Universities Arthritis index (WOMAC) was 79.4. Three patients underwent THA and 1 patient died in an accident. Finally, 11 patients (14 hips) were available for ≥ 2-year follow-up. At the last follow-up, no surgery-related complications occurred, and 14 of 17 hips (82%) were able to perform daily activities without THA requirement. There was no significant decrease in lesion size between any 2 intervals on MRI. However, widening of high signal intensity bands on T2-weighted images inside the necrotic lesion was observed in 9 of 14 hips (64%); 11 of 14 hips (79%) showed increased vascularity on SPECT/CT at 2 years postoperatively. No significant differences were observed between preoperative and 24-month mean Harris hip score (89.2 vs. 88.6), WOMAC (79.4 vs. 75.7), and UCLA score (5.6 vs. 6.2).ConclusionsOur outcomes suggest that culture-expanded ADMSC implantation is a viable option for ONFH treatment without adverse events.  相似文献   
59.
大网膜移植抑制大鼠脊髓损伤后神经细胞凋亡的实验研究   总被引:2,自引:0,他引:2  
目的 探讨脊髓损伤(SCI)后神经细胞凋亡的发生机制和伤后立即行大网膜脊髓移植是否对神经细胞凋亡具有抑制作用。方法 制作程控电磁吸铁棒下落打击脊髓损伤模型,运用末端脱氧核苷酸转移酶介导生物素标记(TUNEL)方法检测细胞凋亡,分别观察SCI后1d、2d、7d组与伤后即刻施行大网膜移植组(存活7d)的细胞凋亡。结果 脊髓灰质区在伤后1d、、2d时TUNEL阳性细胞数最多;脊髓白质区在伤后1d时TUNEL阳性细胞数最多,伤后7d出现第2次高峰;伤后大网膜脊髓移植的TUNEL阳性细胞数较7d明显降低。结论 SCI后白质区和灰质区存在不同演变过程的神经细胞凋亡,SCI后即刻大网膜脊髓移植对细胞凋亡有抑制作用。  相似文献   
60.
郭建军  刘维永  卢春蓉  刘慧玲 《医学争鸣》2001,22(15):1381-1383
目的 用免疫组织化学方法检测家兔胸部火器伤后各组织中TNF-α的表达,探讨其伤后表达变化规律。方法 64只家兔随机均分8组,除正常对照组外均用5.56mm小口径步枪距离6m射击兔右下胸第八肋间锁骨中线外1cm处造成前后胸贯通伤,经指袢排气及消毒缝闭胸壁伤口等简单救治,致伤7组家兔分为伤后0.5,1,6,24和72h,7d,30d取材组,每只均取伤肺距伤道2mm处、1cm处,邻叶中部、与伤道对应的对侧肺处、左室壁、肝肾、脑、垂体、肾上腺取组织标本,行免疫组织化学染色检测组织TNF-α表达。结果 伤后0.5h各组织中TNF-α表达即升高(P<0.01),6h已达高峰,持续数天,7d后降低,30d后与伤前无明显差别。不同时间组同一组织TNF-α表达定位基本相同,而表达强度有所不同。结论 家兔胸部火器伤后各组织中TNF-α表达明显升高并与损伤时间密切相关,同一组织TNF-α表达定位基本相同,TNF-α在各组织中表达强度一定程度上反映了动物伤情。  相似文献   
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