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101.
Laparoscopic enucleation of a renal cell carcinoma   总被引:1,自引:0,他引:1  
The purpose of this study was to report on the feasibility of laparoscopic excision of renal cell carcinoma. An 81-year-old female with renovascular disease underwent a laparoscopic excisional operation for a 2-cm tumor localized in the left kidney.Pathological evaluation showed a low-grade tumor without any extension through the renal capsule (grade I Hand Broder, stage I Robson). The postoperative course was uneventful; there was minimal postoperative pain. The patient was discharged home on the sixth day. Laparoscopic excision would appear to be a safe and effective technique in selected cases.  相似文献   
102.
Abstract Kidney cells are an important source of immunoregulatory molecules that regulate cell-to-cell interactions, which is the key step in the generation of the immunoresponse to alloantigens. In this study we identified the cytokines that are produced by both lymphoid cells and kidney cells when coincubated in mixed kidney lymphocyte cultures (MKLC). The capacity of kidney cells to stimulate the proliferation of effector allogeneic lymphocytes was assayed by incubating irradiated kidney cells and lymphocyte. The cytokine secretion profile in MKLC was investigated by incubating monolayers of kidney cells with effector peripheral blood mononuclear cells (PBMC). The culture supernatants were harvested on days 1, 2, 3, 4, 5, 6, 7, and 8 and assayed for IL-1β, IL-2, IL-6, and TNF alpha using an ELISA. Kidney cells, in comparison to PBMC stimulator cells were poor stimulators of the allo-proliferation even when HLA expression was increased by IFN gamma treatment. Compared to lymphocyte or kidney cells incubated alone, MKLC induced a considerable stimulation of cytokine production. This increase in cytokine production was observed essentially for IL-2 and IL-6 (at day 3, a 10-fold increase in IL-2 and a 5-fold increase in IL-6). This study provided evidence that target kidney cells and effector lymphocyte interactions generate a number of cytokines such as IL-11, IL-2, IL-6, or TNF alpha. These cytokines are known to modulate alloproliferation and generation of cytotoxic J lymphocytes (CTL).  相似文献   
103.
A deceased donor (DD) allocation system incorporating net life survival benefit has been proposed. In this system, many kidneys will be shifted to younger recipients, thereby decreasing their waiting times. The goal of this study was to determine the potential effects of altering waiting times on the likelihood of live donor kidney transplantation (LDKT). We analyzed 93,727 waiting list candidates to determine the association of various patient factors with likelihood of LDKT. The proportion of patients receiving LDKT was compared by the median DD waiting time at that patient's transplant center for someone of that patient's age category and race. LDKT was consistently higher as waiting times became longer. After adjusting for all other factors associated with likelihood of LDKT, waiting time remained a significant, independent predictor. Patients with the longest DD waiting times had 2.3-fold higher odds of LDKT (95% CI 2.11-2.58, p < 0.001). In planning the new DD allocation policy, we must account for resulting alterations in LDKT. It is possible that shifting DD kidneys to younger recipients may decrease LDKT or shift it to older recipients, net effects not consistent with the goal of net life survival benefit.  相似文献   
104.
微血管密度和p16基因表达对判定肾癌生物学行为的意义   总被引:1,自引:0,他引:1  
目的 :探讨肿瘤内的微血管密度 (IMD)和 p1 6基因表达与肾细胞癌 (RCC)生物学行为的关系。 方法 :采用免疫组织化学方法 ,对 76例RCC患者的根治性肾切除标本 ,检测第Ⅷ因子相关抗原和 p1 6基因表达 ,分析IMD、p1 6基因表达与RCC分期、分级及预后的相关性。 结果 :IMD随临床分期升高而增加 (P <0 .0 5 ) ,而与分级无明显相关性 (P >0 .0 5 ) ,随访 5年内死亡者IMD明显升高 (P <0 .0 1 ) ;癌旁组织中 p1 6阳性率 (75 .0 % )显著高于RCC组织 (4 8.7% ) ,p1 6阳性表达随临床分期、病理分级升高而降低 (P <0 .0 5 ) ,而与IMD呈负相关性。结论 :IMD是预测RCC恶性行为的一个有用指标 ,IMD和p1 6基因表达可为RCC的疗效和预后判定提供重要的资料。  相似文献   
105.
良性占位性病变误诊为肾癌的原因分析   总被引:8,自引:0,他引:8  
目的 提高肾脏良恶性占位的诊断水平 ,降低误诊率。 方法 肾占位性病变患者 12例 ,年龄 35~ 6 9岁 ,平均 5 2岁。腰部胀痛不适 9例 ,其中 2例伴全程血尿 ;体检超声偶然发现肾脏占位 3例。术前均行超声、CT等影像学检查诊断为肾癌。 结果  12例患者均手术治疗。术中行冰冻病理检查 7例 ,提示为肾脏良性占位 ,行肿块剜除或单纯肾切除术 ;按肾癌行根治术 5例 ,术后病理均为肾脏良性病变。随访 1~ 3年 ,无复发。 结论 临床医师不应过高评价CT及超声等影像检查的诊断学意义 ,对无法确诊病例可行手术探查 ,术中行冰冻病理检查提高确诊率。多数误诊的良性肾占位与肾癌的影像学表现不同。  相似文献   
106.
肾癌多中心病灶发生机理的探讨   总被引:7,自引:0,他引:7  
目的 探讨肾癌多中心病灶的发生机理。 方法 肾癌根治术标本 10 2例 ,间隔 3mm切开检查切面 ,原发灶外可疑处取材证实肾癌者为多中心灶阳性。免疫组化法检查肾癌原发灶及多中心灶p5 3、PCNA、c erbB2 、CD44 v6、bcl 2、nm2 3 H1 蛋白表达情况。 结果 多中心灶发生率为 15 .7%( 16 10 2 ) ,16例多中心性肾癌中 ,原发灶与多中心灶p5 3、PCNA、c erbB2 、CD44 v6、bcl 2、nm2 3 H1 蛋白表达情况均相近 ,统计学处理差异无显著性意义 (P均 >0 .4)。 结论 肾癌多中心灶具有与原发灶相似的生物学特征 ,其发生以原发灶肾内转移可能性大。  相似文献   
107.
肾恶性肿瘤肾外供血动脉的来源及临床意义   总被引:1,自引:0,他引:1  
目的研究肾恶性肿瘤肾外动脉供血的形成机制,以指导介入治疗。方法对141例肾恶性肿瘤患者,常规进行腹主动脉造影及选择性可疑供血动脉造影,分析其肾外供血动脉的特征及形成机制。结果141例患者中51例有肾外供血动脉(共87支),这些患者肿瘤均突破肾包膜;90例无肾外供血动脉,其中50例肿瘤突破肾包膜,40例肿瘤未突破肾包膜,两者差异有统计学意义(X^2=31.64,P<0.01)。肾外供血动脉的来源与肿瘤发生的部位有关。结论明确肾恶性肿瘤肾外供血动脉的来源,对于指导临床治疗具有重要的意义。  相似文献   
108.
Laparoscopic nephron-sparing surgery for the small exophytic renal mass.   总被引:1,自引:0,他引:1  
OBJECTIVES: Nephron-sparing surgery has emerged as the treatment of choice for the incidentally detected small renal mass, especially those less than 4 cm in size. We describe our technique and experience with the laparoscopic excision of these lesions. METHODS: Between June 2001 and October 2003, 20 patients underwent nephron-sparing surgery at our institution. Twenty-one laparoscopic partial nephrectomy procedures were performed. All tumors were detected incidentally by cross-sectional imaging. All patients had a solid renal mass or a complex cystic renal mass of Bosniak category III or greater. All solid tumors were exophytic and less than 4cm in diameter. Both transperitoneal and retroperitoneal approaches were used. Hemostasis was achieved without hilar control in 20 of the 21 cases. RESULTS: Twenty renal units were approached transperitoneally, and 1 retroperitoneally. Mean tumor size was 2.6 cm (range, 1.2 to 4). Mean estimated blood loss was 211 mL (range, 50 to 500), and mean operative time was 165 minutes. Pathology revealed renal cell carcinoma in 14 (70%). No intraoperative complications occurred. Two patients required blood transfusions postoperatively. CONCLUSION: Carefully selected patients with small, exophytic renal masses can safely undergo laparoscopic excision. When achievable, this procedure can be a more logical alternative to ablative techniques for the minimally invasive management of such lesions.  相似文献   
109.
Prednisone-Free Maintenance Immunosuppression—A 5-Year Experience   总被引:1,自引:0,他引:1  
Concern persists that prednisone-free maintenance immunosuppression in kidney transplant recipients will be associated with an increase in late allograft dysfunction and graft loss. We herein report 5-year follow-up of a trial of prednisone-free maintenance immunosuppression. From October 1, 1999, through January 31, 2005, at our center, 589 kidney transplant recipients were treated with a protocol incorporating discontinuation of their prednisone on postoperative day 6. At 5 years, actuarial patient survival was 91%; graft survival, 84%; death-censored graft survival, 92%; acute rejection-free graft survival, 84% and chronic rejection-free graft survival, 87%. The mean serum creatinine level (+/-SD) at 1 year was 1.6 +/- 0.6; at 5 years, 1.7 +/- 0.8. In all, 86% of kidney recipients with functioning grafts remain prednisone-free as of April 30, 2005. As compared with historical controls, recipients on prednisone-free maintenance immunosuppression had a significantly lower rate of a number of complications, including cataracts (p < 0.001), posttransplant diabetes mellitus (p < 0.001), avascular necrosis (p = 0.001), and fractures (p = 0.004). We conclude that prednisone-related side effects can be minimized in a protocol incorporating prednisone-free maintenance immunosuppression. Five-year graft outcome remains good.  相似文献   
110.
We report here our 10-year experience of a biopsy performed at day 14 after transplantation in 304 patients with stable graft function. The factors that may have influenced subclinical rejection were analyzed according to histology. The incidence of subclinical rejection was 13.2%. Addition of mycophenolate mofetile (MMF) as a primary immunosuppressant significantly decreased the incidence of subclinical rejection compared with patients without such treatment (odds ratio, 0.23; p < 0.05). On the other hand, HLA-DR antigen mismatch (odds ratio, 2.39) and unrelated donor (odds ratio, 2.10) were also significantly associated with decreased subclinical rejection (p < 0.05). The incidence of acute rejection in patients with normal findings was lower than in those with borderline changes or subclinical rejection (0.23 +/- 0.05 vs. 0.48 +/- 0.07 and 0.60 +/- 0.11, respectively; p < 0.05). The graft survival rates in patients with subclinical rejection were lower than in patients with normal or borderline changes at 1 (88.4% vs. 97.9% and 99.1%; p < 0.05), 5 (77.8% vs. 96.2% and 95.9%; p < 0.05) and 10 (62.3% vs. 96.2% and 93.7%; p < 0.05) years. Thus, a protocol biopsy performed on day 14 after transplantation is useful for predicting graft survival. Triple therapy including MMF, related donor and HLA-DR antigen match are important factors for reducing subclinical rejection in living-donor renal transplantation.  相似文献   
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