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71.
Genotyping of platelet alloantigens with the possibility of using any type of cellular material as a source of DNA has become a preferred procedure, particularly in thrombocytopenic patients when platelet counts are too low for phenotyping. Recently human platelet antigen 1 (HPA-1) has been identified as an inherited risk factor for coronary thrombosis. The different detection methods currently used have disadvantages for large-scale DNA diagnosis, including the need for electrophoresis (allele-specific restriction enzyme analysis, amplification with sequence-specific primers) or the potential risk of reduced specificity (allele-specific oligonucleotide hybridization). In this report we describe the adaptation of an automated oligonucleotide ligation assay to genotype HPA-1 in polymerase chain reaction (PCR)-amplified DNA samples. HPA-1a and HPA-1b phenotypes corresponded to the results of the different genotyping assays. The genotypes determined with the ELISA-based PCR-oligonucleotide ligation assay were in 100% concordance with the results obtained by conventional allele-specific restriction enzyme site analysis and PCR amplification with sequence-specific primers. The automated oligonucleotide ligation assay provides a rapid, reliable, nonisotopic method to genotype human platelet antigens that can rapidly be applied to large population screening.  相似文献   
72.
目的:探讨门静脉临床病变类型及超声诊断价值,指导临床治疗及预防。方法:通过120例超声诊断门静脉病变分析总结,对门静脉病变进行归纳分类,指导临床治疗及预防。结果:按门脉节段分类门脉病变分为:①门脉属支病变,②门脉主干病变,③门脉分支病变。每一病变又分门脉血流异常,门脉本身病变,门脉外异常影响门脉。并分析部分异常出现的原因及后果,指导预防及治疗。结论:应用彩超可以评价门脉病变性质、部位,部分指导临床治疗。  相似文献   
73.
A report of a patient with an azygos lobe and an associated anomalous azygos vein covering the upper thoracic sympathetic chain. This anomaly poses a significant risk during the procedure of endoscopic thoracic sympathectomy. A chest X-ray is useful in detecting this anomaly and alerting the surgeon to potential problems.  相似文献   
74.
Background. The optimal management of patients with renal cell carcinoma with inferior vena cava tumor thrombus remains unresolved. Traditional approaches have included resection with or without the use of cardiopulmonary bypass. Chemotherapy has played a minor role except for biotherapeutic agents used for metastatic disease.

Methods. From January 1989 to January 1996, 37 patients with renal cell carcinoma and inferior vena cava tumor thrombus underwent surgical resection. The 27 men and 10 women had a median age of 57 years (range, 29 to 78 years). Thirty-six patients presented with symptoms; 21 had hematuria. Distant metastases were present in 12 patients. Tumor thrombi extended to the infrahepatic inferior vena cava (n = 16), the intrahepatic inferior vena cava (n = 16), the suprahepatic inferior vena cava (n = 3), and into the right atrium (n = 2). All tumors were resected by inferior vena cava isolation and, when necessary, extended hepatic mobilization and Pringle maneuver, with primary or patch closure of the vena cavotomy. Cardiopulmonary bypass was necessary in only 2 patients with intraatrial thrombus.

Results. Complications occurred in 11 patients, and 1 patient died 2 days postoperatively of a myocardial infarction (mortality, 2.7%). Twenty patients are alive; overall 2- and 5-year survival rates were 61.7% and 33.6%, respectively. For patients without lymph node or distant metastases (stage IIIa), 2- and 5-year survival rates were 74% and 45%, respectively. The presence of distant metastatic disease (stage IV) at the time of operation did not have a significant adverse effect on survival, as reflected by 2- and 5-year survival rates of 62.5% and 31.3%, respectively. Lymph node metastases (stage IIIc) adversely affected survival as there were no long-term survivors.

Conclusions. Resection of an intracaval tumor thrombus arising from renal cell carcinoma can be performed safely and can result in prolonged survival even in the presence of metastatic disease. In our experience, extracorporeal circulatory support was required only when the tumor thrombus extended into the heart.  相似文献   

75.
Thromboembolism constitutes one of the most dangerous complications during the immediate postoperative period of prosthetic surgery. Pharmacological prophylaxis and mechanical vascular compression are not always sufficient to protect from this surgical complication. In patients at greatest risk for thromboembolism, often with a positive history for pulmonary embolism, temporary vena cava filters may be used to reduce the incidence of vascular and pulmonary complications. However useful, these filters cannot be routinely used in orthopedic surgery. We present our results with the use of Filcard RFO2 vena cava filters in an open, randomized study of 30 patients. Received: 5 November 2001/Accepted: 30 November 2001  相似文献   
76.
四肢带表浅静脉干的局部皮瓣在创伤修复中的应用   总被引:1,自引:0,他引:1  
设计4种带表浅静脉干的局部皮瓣用于修复四肢创面14例,获得了满意的效果。该皮瓣所包含的一条浅静脉干,不仅有利于静脉回流,且其血流对皮瓣亦有营养作用。因此,该皮瓣容易成活,长宽比值可大于传统任意型皮瓣。并具有操作简便,不损伤主要动脉等优点。文中介绍了皮瓣的设计及手术方法,并对该皮瓣的血液循环特点、适应证及供区选择等进行了讨论。  相似文献   
77.
目的:研究肝癌合并门脉癌栓综合治疗的效果。方法:122例肝癌分为2组:A组(72例)行肝动脉化疗栓塞(TACE);B组(50例)行TACE结合外放射治疗。结果:A组1、2年生存率分别为22.3%、4.5%,平均生存期7.5个月;B组1、2、3年生存率分别为39.2%、21.2%、13.5%,平均生存期17.5个月,P<0.05。结论:对合并门脉癌栓的肝癌综合治疗能明显提高治疗效果。  相似文献   
78.
BACKGROUND/AIMS: Catheterization of the femoral vein is a safe and recommended method of temporary access for haemodialysis. In some patients, however, because of the lack of other possibilities, it is necessary to maintain long-term femoral cannulation. The aim of the study was to evaluate the frequency of stenosis after prolonged femoral cannulation. METHODS: The 24 patients incorporated in the study were divided into two groups. Group 1 consisted of 10 end-stage kidney failure patients (four females and six males, aged 32-75 years, average 55.6+/-13.6 years) in whom femoral catheters were maintained for less than 2 weeks (5-14 days, average 9.3+/-3.6 days). Group 2 included 14 chronic haemodialysis patients (six females and eight males aged 23-65 years, average 49.5+/-13.27 years). The time of catheter maintenance ranged from 2 to 16 weeks (average 6.4+/-4.2 weeks). Femoral and iliac vein status was evaluated using magnetic resonance imaging. RESULTS: A feature of venous stenosis of both the femoral and iliac veins was disclosed in four patients in whom femoral cannulation lasted more than 4 weeks. There were no stenoses in group 1. CONCLUSION: Long-term femoral cannulation for more than 4 weeks may be associated with a significant risk of stenosis in the femoral and/or external iliac veins.  相似文献   
79.
The most serious problem regarding a laparoscopic partial nephrectomy is how to perform bloodless excision without causing renal ischemia in a limited working space. We report the case of a 65-year-old man with left small renal cell carcinoma in the posterior mid zone who underwent a laparoscopic partial nephrectomy through a retroperitoneal approach by carrying out the ligation of the tumor-feeding artery, but without clamping the renal pedicle. Both preoperative abdominal computed tomography (CT) and intraoperative ultrasonography revealed the tumor to be fully encapsulated. The tumor-feeding artery could be exposed by dissection from the renal hilum and, after an arterial ligation, tumor resection with a safety margin was smoothly performed with minimal bleeding. Postoperatively, CT revealed a limited defect of the renal parenchyma and excretory pyelography showed no urine leakage or urinary tract obstruction. The preoperative and postoperative creatinine levels were 0.66 and 0.69 mg/dL, respectively. As a result, a tumor-feeding artery ligation with a laparoscopic partial nephrectomy for left renal cell carcinoma in the posterior mid zone is considered to be an effective surgical modality which avoids renal ischemia and pelvic heat injury.  相似文献   
80.
目的 通过研究三氧化二砷(As2O3)对人脐静脉内皮细胞(HUVEC)中蛋白激酶C(PKC)活性和白细胞介素(IL)-15表达和分泌的影响,探讨内皮细胞在As2O3抑制白血病或肿瘤中的作用。方法用不同浓度的As2O3作用于培养的HUVEC细胞,测定其生长情况、胞膜和胞浆PKC活性以及对IL-15基因表达和分泌的影响。结果0.25 μmol/L~50 μmol/L的.As2O3均抑制HUVEC细胞的增殖(P<0.01),随着药物浓度或作用时间的增加,细胞逐渐死亡。在As2O3作用细胞4 h测定胞浆和胞膜的PKC活性,两者在不同浓度作用下活性水平均得到提升(P<0.01),但胞膜的活性上升幅度更大。在As2O3的测定浓度范围内,PKC的活性水平与As2O3的浓度呈正相关。1、5、16 μmol/L的As2O3导致IL-15基因表达和分泌水平的增加(P<0.01),并呈浓度依赖性关系。结论As2O3可能是通过激活内皮细胞的PKC活性,促进IL-15或其他细胞因子的分泌,来抑制白血病或肿瘤发展的。  相似文献   
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