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131.
OBJECTIVE: To better determine the role of portal vein resection and its effect on survival, as well as to appreciate the impact of portal vein invasion on prognosis in hilar cholangiocarcinoma. SUMMARY BACKGROUND DATA: Hepatectomy with portal vein resection is sometimes performed for locally advanced hilar cholangiocarcinoma. However, the significance of microscopic invasion of the portal vein has not been determined. METHODS: Medical records of 160 patients with hilar cholangiocarcinoma who underwent macroscopically curative hepatectomy with (n = 52) or without portal vein resection (n = 108) were reviewed. Invasion of the portal vein was assessed histologically on the surgical specimen, and results were correlated with clinicopathologic features and survival. RESULTS: Surgical mortality, including all hospital deaths, was similar in patients who did and did not undergo portal vein resection (9.6% vs. 9.3%), but the primary tumor was more advanced in patients who underwent portal vein resection. Histologically, no invasion was found in 16 (30.8%) of resected portal veins. However, dense fibrosis adjacent to the portal vein was common, and the mean distance between the leading edge of cancer cells and the adventitia of the portal vein was 437 +/- 431 mum. The prognosis was worse in patients with than without portal vein resection (5-year survival, 9.9% vs. 36.8%; P < 0.0001). The presence or absence of microscopic invasion of the resected portal vein did not influence survival (16.6 months in patients with microscopic invasion vs. 19.4 months in those without; P = 0.1506). Multivariate analysis identified histologic differentiation, lymph node metastasis, and macroscopic portal vein invasion as independent prognostic factors. CONCLUSIONS: Microscopic invasion of the portal vein may be misdiagnosed clinically in patients with hilar cholangiocarcinoma. However, the distance between tumor and adventitia is so narrow that curative resection without portal vein resection is unlikely to be possible. Gross portal vein invasion has a negative impact on survival, and hepatectomy with portal vein resection can offer long-term survival in some patients with advanced hilar cholangiocarcinoma.  相似文献   
132.
The use of intraoperative angiography to monitor graft patency was retrospectively reviewed in extracranial-intracranial bypass procedures. Forty-two patients underwent 43 extracranial-intracranial bypass procedures with the use of intraoperative angiography. Superficial temporal artery (STA)-middle cerebral artery (MCA) bypass was performed in 41 patients (42 procedures) with ischemic cerebrovascular diseases, and vertebral artery-MCA bypass using radial artery graft for intentional ligation of the common carotid artery in one patient with nasopharyngeal carcinoma. Intraoperative angiography provided high-quality subtraction images in every case. There were no complications due to angiography. Graft occlusion was observed intraoperatively in three cases, but an additional procedure reopened the occluded graft in all three cases. Graft patency rate was 100% after surgery. Outcome was excellent in 40 patients and good in one patient who underwent STA-MCA bypass. Intraoperative angiography provides useful information regarding graft patency during bypass surgery. Intraoperative assessment prior to wound closure allows for the recognition and correction of technical failure and decreases the risk of postoperative complications.  相似文献   
133.
We have experienced two cases of interstitial nephritis with Sj?gren's syndrome successfully treated by steroid therapy. Case 1. A 50-year-old woman was admitted because of rash and arthralgia of the limb. Although her renal function was normal, serum IgG was extremely high and gallium-67 scintigrams indicated abnormal uptake in both kidneys with swelling on CT scans. Renal biopsy specimens showed a patchy dense interstitial infiltration of lymphocytes, monocytes and partly plasma cells with tubular cell atrophy. To suppress an excessive immune reaction, oral prednisolone was administrated at a dose of 30 mg/day. Six weeks after inception of the therapy, re-biopsy specimens showed a decrease in interstitial infiltration, particularly plasma cells, and interstitial fibrosis did not progress. After 8 weeks, the serum IgG level was normalized. Case 2. A 57-year-old woman was found to have renal involvement(serum creatinine level: 2.2 mg/dl) and anemia. Clinical findings suggested primary Sj?gren's syndrome with renal tubular acidosis. Renal biopsy specimens showed a moderate to severe interstitial infiltration of inflammatory cells. After inception of steroid therapy(prednisolone 40 mg/day), renal involvement and renal anemia gradually improved. The renal function has been kept stable(serum creatinine level: 1.5 mg/dl) for 9 years by low-dose steroid therapy. These two cases suggest that steroid therapy plays two important roles: controlling of the acute immune reaction that causes renal fibrosis to progress in case 1, and long-term preservation of the renal function by the continuous use of low-doses in case 2.  相似文献   
134.
Okada Y  Eibl G  Duffy JP  Reber HA  Hines OJ 《Surgery》2003,134(2):293-299
BACKGROUND: We have previously reported that the glial cell-derived neurotrophic factor (GDNF) promotes pancreatic cancer cell invasion in vitro. The purpose of this study was to determine whether GDNF regulates the expression and activation of matrix metalloproteinase-9 (MMP-9) in human pancreatic cancer cells. METHODS: We used human pancreatic cancer cell line MIA PaCa-2. The effect of GDNF on mRNA and protein expression was measured by Northern blot, Western blot and enzyme-linked immunosorbent assay. MMP proteolytic activity was detected by gelatin zymography. To determine which intracellular pathways were involved, we used the following inhibitors: tyrosine kinase inhibitor Genistein, MEK-1 inhibitor PD98059 and PI3-K inhibitor Wortmannin. RESULTS: GDNF increased MMP-9 mRNA and protein expression in MIA PaCa-2 cells in a dose-dependent manner. Treatment with GDNF enhanced gelatinolytic activity of the pro and active form of MMP-9. Inhibitor experiments showed that the expression and activity of pro MMP-9 was totally inhibited by Genistein and partially by Wortmannin, whereas PD98059 had no effect. All three compounds inhibited the activity of the active form of MMP-9. CONCLUSIONS: GDNF upregulates the expression and enzymatic activity of MMP-9 through different signaling pathways in MIA PaCa-2. These findings suggest that GDNF modulates MMP-9 expression and activation, and this may promote pancreatic cancer invasion.  相似文献   
135.
Aortic arch replacement with proximal first technique.   总被引:2,自引:0,他引:2  
BACKGROUND: Deep hypothermic circulatory arrest (DHCA) without retrograde cerebral perfusion (RCP) has a strict time limit. We modified a surgical technique for anastomosis to shorten the period of DHCA and unilateral cerebral perfusion (UCP). METHODS: Between March 1993 and August 2001, retrospective analysis was done on 23 consecutive patients, who underwent aortic arch replacement with branches. The patients were divided into two groups: DHCA group and UCP group. The DHCA group, in which DHCA alone and without additional cerebral perfusion was performed, comprised of nine patients. Proximal aortic anastomosis was performed first during systemic cooling; then both the brachiocephalic artery and left carotid artery were reconstructed with the branches of the artificial graft during circulatory arrest; thereafter, cerebral and coronary perfusions were resumed. The UCP group, in which DHCA was not used but right hemisphere perfusion during deep hypothermia was performed when the origin of brachiocephalic artery was safely clamped, consisted of 14 patients. RESULTS: Mean time of DHCA was 18.8+/-4.2 minutes and that of right hemisphere perfusion time was 11.0+/-3.8 minutes, respectively. Twenty-one patients survived the surgery (91.3%), and two (8.7%) died during hospitalization. Transient cerebral complication occurred in four patients in the DHCA group and all recovered. Logistic regression analysis revealed that DHCA was the only parameter to significantly influence temporary neurological dysfunction. There was no other significant difference between the two groups. CONCLUSION: With our modified and simple surgical technique for aortic arch repair, we were able to successfully shorten the DHCA time and right hemisphere perfusion time. However, because DHCA was the only parameter to significantly influence temporary neurological dysfunction, some form of continuous cerebral perfusion at deep hypothermia may be a safer method to preserve cerebral function.  相似文献   
136.
Our purpose was to improve the sharpness of the coronary stent and lumen. We reconstructed volume rendering (VR) image and maximum intensity projection (MIP) images using the original image and a sharpened operator image with 8-neighbor Laplacian filter. The most suitable center number was 9, and the circumferential number was -1 on the sharpened operator image with 8-neighbor Laplacian filter. In the same way, the most suitable spatial filter was the FC43. VR and MIP images showed sharp stents. The VR image and MIP image fused the original image and sharpened the operator image with the 8-neighbor Laplacian filter, resulting in a clear lumen. The 8-neighbor sharpened operator image with 8-neighbor Laplacian filter was attached to the Aquilion64, and this method did not require extra hardware and software for reconstructing images of the stent and lumen.  相似文献   
137.
BACKGROUND: The dorsal subsegmental intrahepatic bile duct in the right anterior superior segment (B8c) sometimes joins the posterior sectorial duct. In such cases it can be misidentified as the right posterior superior segmental duct (B7). However, there are no published studies on the confluent pattern of B8c. MATERIALS AND METHODS: We studied B8c in the resected liver of 107 patients (65 with bile duct carcinoma and 42 with gallbladder carcinoma) who had undergone right hepatectomy or more extensive right-sided liver resection. RESULTS: B8c was identified in all cases. It joined the right posterior sectorial duct or B7 in 18 cases (16.8%). In 12 cases B8c joined independently the posterior sectorial duct or B7. In 6 cases B8c joined the posterior sectorial duct after making the common duct with the lateral subsegmental duct in the anterior superior or anterior inferior segment (B8b or B5c). CONCLUSIONS: B8c does not join the anterior sectorial bile duct in every sixth case.  相似文献   
138.
Although the ability of the liver to regenerate to a predetermined size after resection made adult-to-adult living donor liver transplantation (LDLT) possible, there is little information regarding the growth regulatory mechanism for a small-for-size graft. Forty-one cases of LDLT were divided into two groups by graft volume to standard liver volume ratio (GV/SLV); small graft group (Group S, GV/SLV<40%, n=16) and non-small graft group (Group NS, GV/SLV>40%, n=25). The regeneration rate (GV at 1 week/harvested GV) and serum levels of hepatocyte growth factor (HGF), transforming growth factor- (TGF-) and transforming growth factor-1 (TGF-1) were compared between two groups. The regeneration rates in Group S were significantly higher than that of Group NS (217±12% and 178±10%, respectively, P<0.01). The serum HGF levels of Group S were significantly higher than those of Group NS on POD 1. The TGF-1 levels of Group S were significantly higher than those of Group NS on POD 3 and 5. The TGF- levels were not different at any time points studied. These results indicate that a small-for-size graft retains the capacity to regenerate faster by modulation of expression pattern of HGF and TGF-1 immediately after LDLT. After the acceleration of the regenerative response by HGF, subsequent elevation of TGF-1 synergistically controls graft size, regulating uncontrolled proliferation of hepatocytes.  相似文献   
139.
We experienced a rare case of giant cell tumor (GCT) arising in the 5th rib involving the 5th vertebral body and transverse process. A 57-year-old man presented with a well-defined mass in the left thoracic cavity on chest x ray examination. Chest computed tomography showed a heterogeneous 7cm-diameter mass originating in the posterior segment of the left 5th rib. The tumor had spread to the 5th thoracic vertebra destroying the left half of the body and transverse process. Magnetic resonance imaging showed a heterogeneous-intensity mass involving the 4th to 6th ribs. A radical excision of the tumor followed by a 50 Gy radiotherapy was performed after embolization of the feeding arteries. The pathological diagnosis was a GCT. The patient remains well without evidence of recurrence for 6 years following surgery. The present case is only the 14th case of GCT arising in the rib to have been reported in Japan.  相似文献   
140.
Color Doppler ultrasound for detection of renal arteriovenous fistulas   总被引:2,自引:0,他引:2  
OBJECTIVES: Renal arteriovenous (AV) fistula is uncommon, but sometimes causes severe hematuria. To assess the value of color Doppler ultrasound (CD-US) for the detection of renal AV fistula, we retrospectively reviewed our experience with this disease. MATERIALS AND METHODS: Between 1994 and 2001, five patients with renal AV fistula were diagnosed in our institution. Post-biopsy AV fistula of the transplanted kidney was found in 1 patient. Renal AV fistula was detected in 2 patients who presented with gross hematuria. In the remaining 2 patients, renal AV fistula was discovered incidentally during abdominal ultrasonography. We evaluated gray-scale and CD-US imaging in those five patients. RESULTS: In all 5 patients, CD-US showed a whirling flow pattern within an echo-free structure suggesting AV fistula. However, it was difficult to distinguish AV fistula from aneurysm using only CD-US. While pulsed spectral Doppler evaluation of the lesion might be helpful, prompt venous filling on dynamic CT scan and/or renal arteriography was the most definitive sign for diagnosing the renal AV fistula. CONCLUSIONS: CD-US is excellent for demonstrating turbulent blood flow signals within the kidney. However, another radiographic study is required to give a definite diagnosis of renal AV fistula. Due to its low cost, low risk and wide availability, we recommend that CD-US be the first-line imaging procedure for the evaluation of hematuria and renal cystic lesion as well as for followup for renal AV fistula.  相似文献   
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