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51.
Pancreaticoduodenectomy after placement of endobiliary metal stents   总被引:2,自引:0,他引:2  
Contemporary treatment programs for patients with potentially resectable pancreatic cancer often involve preoperative therapy. When the duration of preoperative therapy exceeds 2 months, the risk of plastic endobiliary stent occlusion increases. Metal stents have much better patency but may complicate subsequent pancreaticoduodenectomy (PD). We evaluated rates of perioperative morbidity, mortality, and stent complications in 272 consecutive patients who underwent PD at our institution from May 2001 to November 2004. Of these 272 patients, 29 (11%) underwent PD after placement of a metal stent, 141 underwent PD after placement of a plastic stent, 10 had PD after biliary bypass without stenting, and 92 had PD without any form of biliary decompression. No differences were found between the Metal Stent group and all other patients in median operative time, intraoperative blood loss, or length of hospital stay. No perioperative deaths occurred in the Metal Stent group versus 3 (1.2%) deaths in the other 243 patients. The incidence of major perioperative complications was similar between the two groups, including the rates of pancreatic fistula, intra-abdominal abscess, and wound infection. Furthermore, there were no differences in the perioperative morbidity or mortality rates between patients who underwent preoperative biliary decompression with a stent of any kind (metal or plastic) and those patients who underwent no biliary decompression at all. Metal stent-related complications occurred in 2 (7%) of 29 patients during a median preoperative interval of 4.1 months; in contrast, 75 (45%) of the 166 patients who had had plastic stents experienced complications, including 98 stent occlusions, during a median preoperative interval of 3.9 months (P < 0.001). We conclude that the use of expandable metal stents does not increase PD-associated perioperative morbidity or mortality, and as such an expandable metal stent is our preferred method of biliary decompression in patients with symptomatic malignant distal bile duct obstruction in whom surgery is not anticipated, or in whom there is a significant delay in the time to surgery. Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18, 2005 (oral presentation). Supported by the Lockton Fund for Pancreatic Cancer Research, The University of Texas M. D. Anderson Cancer Center, Houston, Texas.  相似文献   
52.
The role of endoscopic retrograde cholangiopancreatography (ERCP) in the preoperative assessment of anomalous pancreaticobiliary junction was retrospectively evaluated in 74 consecutive patients (19 males and 55 females; aged 0–80 years). Sixty-three patients had congenital biliary dilatation and 11 did not. Type classification of congenital biliary dilatation was possible by ERCP alone in 45 patients (71%). The main causes of classification failure were previous bilio-enteric anastomosis and restriction of postural changes during ERCP due to general anesthesia in pediatric patients. Classification of anomalous junction was possible in 69 patients (93%). Technical difficulty in ERCP caused classification failure in 5 patients. Neoplastic lesions were found in 12 patients (16%) and all but 1 were correctly diagnosed by ERCP. We conclude that ERCP plays an important role in the preoperative diagnosis and type classification of anomalous pancreaticobiliary junction and congenital biliary dilatation.  相似文献   
53.
Laparoscopic cholecystectomy is associated with a two-to-four times higher risk of bile duct injury (BDI) than open cholecystectomy. BDI can lead to significant morbidity and even mortality. The first priority in BDI is to control peritoneal and biliary sepsis and to convert an acute BDI to a controlled external biliary fistula (EBF) — this can be achieved by endoscopic and/ or radiological intervention in most cases. This should be followed by assessment of the extent of injury — both biliary and vascular. Immediate management of BDI recognized during cholecystectomy depends on the type of injury, the condition of the patient, and the experience of the surgeon. For BDI recognized after cholecystectomy, early repair is not recommended, as the results are poor. The EBF may evolve into a benign biliary stricture (BBS), which should be electively repaired by a Roux-en-Y hepatico-jejunostomy. The use of an endoscopic stent as definitive management of BDI is not recommended. Long-term follow-up is essential after the repair of a BBS, as recurrence can occur several years after repair. Recurrent BBS is best treated with endoscopic balloon dilatation. Excellent early and long-term results can be obtained in specialized units at tertiary care referral centers.  相似文献   
54.
Abstract: Fifty -two patients with primary biliary cirrhosis (PBC), 10 of whom were 65 years or older at the time of diagnosis, were investigated by laparo-scopy. Laparoscopic findings in these 10 patients were evaluated and compared with those in younger patients. The 10 cases were composed of nine females and one male, and two had been diagnosed as having symptomatic PBC with skin itching, while the remaining eight had asymptomatic PBC. Two, seven and one case were in Scheuer's stage I, II and III, respectively, and eight had chronic non-suppurative destructive cholangitis (CNSDC) on liver biopsy specimens. The majority of senescent PBC patients had typical findings of the early stage of PBC on the liver surface; mild undulations in nine and reddish patches in eight. The laparoscopic findings in senescent PBC were relatively mild.  相似文献   
55.
Summary The absorption of almitrine from the upper gastrointestinal tract has been evaluated in 6 healthy volunteers by an intubation technique. Almitrine bismesylate dissolved in malic acid was introduced into the stomach after homogenization with a meal containing the marker14C-polyethylene glycol (PEG) 4000. Unlabeled PEG 4000 was infused into the second part of duodenum throughout the experiment. Samples of the luminal content were collected every 15 min for four hours from the stomach and at the ligament of Treitz. Blood was also collected.Almitrine was neither absorbed from nor metabolized in the stomach. About 37% of the quantity of drug emptied from the stomach was absorbed from the duodenum. Almitrine was detected in plasma 50 min after ingestion of the meal and its plasma concentration-time profile reflected the cumulative gastric emptying rate. The metabolite tetrahydroxy almitrine was found in intestinal samples as soon as unchanged drug was detected in plasma. The intraluminal rate of formation of the metabolite increased with time.The results suggest hepatic metabolism of almitrine followed by rapid excretion of the metabolite in the bile.  相似文献   
56.
治疗肝胆管结石并高位胆管狭窄74例。术中通过高位胆管的充分暴露,1~3级胆管切开整形、肝切除的正确应用,纤维胆道镜检及取石,大口胆肠内引流等多种手术的联合使用,提高了手术疗效,降低了残石率.认为术前详细的路道影像学检查、对手术难度的充分预测、术式的正确选择等非常重要.强调术中病肝切除的重要性.  相似文献   
57.
对29例亚急性重症肝炎及13例次淤胆性肝炎肝穿刺标本的光、电镜检查,测算了18例亚急性重症肝炎,9例淤胆性肝炎肝细胞内淤胆的容积百分比、胆汁凝固性坏死的容积百分比与临床资料进行统计学处理,指出这两类肝炎都有肝细胞内淤胆和胆汁凝固性坏死,但淤胆性肝炎肝小叶结构完整,胆汁流出道不破坏,亚急性重症肝炎肝小叶破坏。认为除肝细胞大量坏死外,胆汁流出道破坏是影响预后的另一个重要因素。本文详细描述了胆计凝固性坏死的超微结构改变。  相似文献   
58.
We have recently reported differences in the hematopoiesis between autoimmune hepatitis type 1 (AIH-1) and primary biliary cirrhosis (PBC). In view of the notion that cytokines are regulators of hematopoiesis, we investigated in our tertiary center the cytokine production in the bone marrow (BM) of the same consecutive cohort of patients (13 AIH-1, 13 PBC, 10 healthy and 7 patients with cirrhosis due to chronic hepatitis B). Interferon-gamma (IFN-gamma), interleukin-4 (IL-4), interleukin-10 (IL-10), tumor necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta (TGF-beta) were determined in the supernatants of long-term BM cultures by ELISAs. IL-4, TNF-alpha and TGF-beta were found significantly increased in the BM of PBC patients compared to AIH-1 and both control groups. AIH-1 patients had significantly higher BM IL-10 compared to PBC patients and higher IL-10, IL-4 and TNF-alpha compared to controls. BM IFN-gamma was significantly higher in PBC and AIH-1 patients compared to controls. In AIH-1 patients, IL-10 was positively correlated with CD34+, CD34+/CD38- and CD34+/CD38+ cell proportions. In conclusion, the BM cytokine microenvironment of PBC and AIH-1 patients differs significantly compared to that of healthy individuals and cirrhotic patients of non-autoimmune etiology. Differences were also found between patients with PBC and AH-1. The implication of BM in the pathogenesis of autoimmune liver diseases is possible and needs further investigation.  相似文献   
59.
Intrahepatic bile ducts (IHBDs) are indispensable for transporting bile secreted from hepatocytes to the hepatic duct. The biliary epithelial cells (BECs) of the IHBD arise from bipotent hepatoblasts around the portal vein, suggesting the portal mesenchyme is essential for their development. However, except for Notch or Activin/TGF-beta signaling molecules, it is not known which molecules regulate IHBD development. Here, we found that FGF receptors and BMP4 are specifically expressed in the developing IHBD and the hepatic mesenchyme, respectively. Using a mesenchyme-free culture of liver bud, we showed that bFGF and FGF7 induce the hepatoblasts to differentiate into BECs, and that BMP4 enhances bFGF-induced BEC differentiation. The extracellular matrix (ECM) components in the hepatic mesenchyme induced BEC differentiation. Forced expression of a constitutively active form of the FGF receptor partially induced BEC differentiation markers in vivo. These data strongly suggest that bFGF and FGF7 promote BEC differentiation cooperatively with BMP4 and ECMs in vivo.  相似文献   
60.
Summary Using wedge liver biopsies from patients with primary biliary cirrhosis (PBC), ultrastructural features of the intrahepatic bile ducts in livers with slight or no bile duct loss were compared with those in livers with advanced bile duct loss and in extrahepatic cholestasis (EHC).Most changes in the biliary epithelium in PBC were similar to those in EHC. Microvillous loss and bleb formation, mitochondrial damage and increase in endoplasmic reticulum and ribosomes were found in PBC irrespective of the degree of bile duct loss, and also in EHC. These changes were present almost equally at any level of the biliary tree, and are presumed to represent a variety of non-specific lesions of biliary epithelial cells. As the loss of bile ducts in PBC progressed, cytoskeletal filaments and cytophagosomes increased in number and basement membranes were more thickened and reduplicated. These changes were more or less conspicuous in smaller branches of the biliary tree, and were also prominent in EHC. They might be causally related to the bile flow disturbance in the liver. Lateral intercellular spaces were irregularly dilated and contained osmiophilic membranous and/or granular material, similar to that found in duct lumena, within and without the basement membrane, and in the cytoplasm of periductal macrophages. Furthermore, pinocytotic vesicles were increased in the biliary cytoplasm facing periphery. These findings suggest possible alteration of the permeability of biliary epithelial cells, probably in the direction from the lumena to the periductal tissue. Such changes were found in PBC livers with virtual absence of bile duct loss, and the significance of this phenomenon is discussed.  相似文献   
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