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991.
The purpose of this study was to evaluate the cause and outcome of biliary anastomotic complications occurring after living related liver transplantation (LRLT). A database of 391 patients undergoing 400 LRLT from June 1990 to August 1998 was reviewed. The overall incidence of biliary anastomotic complications was 18.2% (71 patients). There were 45 bile leaks, 35 anastomotic strictures, and the bile duct was ligated inadvertently in 3 cases. Univariative analysis revealed that the manner of stent usage, intrapulmonary shunting, and gender of recipients were significant risk factors for leakage. Anastomotic leaks, cytomegalovirus infection, hepatic artery complications, and gender of recipients were significant risk factors for stricture. In pediatric patients older than 2 years old, ABO blood type compatibility was another risk factor for leakage and stricture. Choice of stent usage and earlier transplantation for patients with intrapulmonary shunting should reduce the rate of biliary leaks, and prophylaxis of leaks for patients with intrapulmonary shunting, and minimizing hepatic artery complications should reduce the rate of biliary stricture after LRLT. Avoidance of ABO-incompatible donors or innovative immunosuppression in ABO-incompatible transplantation should be considered in children.  相似文献   
992.
This study was designed to determine the optimum treatment for a superficial esophageal cancer involving the mucosal or submucosal layer of the esophagus. The subjects were 150 patients with a superficial esophageal cancer who underwent endoscopic mucosal resection (EMR) or esophagectomy in Kurume University Hospital from 1981 to 1997. The mortality and morbidity rates, survival rate, and recurrence rate were retrospectively compared for (1) 35 patients who underwent EMR and 37 patients who underwent esophagectomy for a mucosal esophageal cancer and (2) 45 patients who underwent extended radical esophagectomy and 33 patients who underwent less radical esophagectomy for a submucosal esophageal cancer. Among the 72 patients with a mucosal cancer, lymph node metastasis/recurrence was observed in only one (1%); whereas of 78 patients with a submucosal cancer it was observed in 30 (38%). Among patients with a mucosal cancer the mortality and morbidity rates after EMR were lower than for those after esophagectomy. The survival rate after EMR was the same as that after esophagectomy. No recurrence was observed after either treatment modality. Among the patients with a submucosal cancer, the survival rate was higher and the recurrence rate lower after extended radical esophagectomy; than after less radical esophagectomy; the mortality and morbidity rates after extended radical esophagectomy were the same as those after less radical esophagectomy. Multivariate analysis demonstrated that the treatment modality (EMR versus esophagectomy) did not influence the survival of patients with a mucosal esophageal cancer, whereas it strongly influenced the survival of patients with a submucosal esophageal cancer. We concluded that EMR was the mainstay of treatment for a mucosal esophageal cancer, and extended radical esophagectomy was the mainstay of treatment for a submucosal esophageal cancer.  相似文献   
993.
1. We investigated the possible involvement of phospholipase A(2) (PLA(2)) and its products in long-term potentiation (LTP) in the CA1 neurotransmission of rat hippocampal slices. 2. Inhibitors of Ca(2+)-independent PLA(2) (iPLA(2)) prevented the induction of LTP without affecting the maintenance phase of LTP whereas Ca(2+)-dependent PLA(2) inhibitors were virtually ineffective, which suggests a pivotal role of iPLA(2) in the initiation of LTP. 3. We then investigated the effect of docosahexaenoic acid (DHA) and arachidonic acid (AA) on BEL (bromoenol lactone, an iPLA(2)-inhibitor) -impaired LTP, and found that either DHA or AA abolished the effect of BEL. However, DHA did not restore BEL-attenuated LTP when applied after the tetanus. DHA per se affected neither the induction nor maintenance of LTP. Linoleic acid had no effects, either. 4. These results suggest that DHA is crucial for the induction of LTP and that endogenously released DHA during tetanus is sufficient to trigger the formation of LTP.  相似文献   
994.
During 28-day culture of bone marrow- and calvaria-derived osteoblasts, the constant presence of parathyroid hormone (PTH)(1-34) retarded differentiation and nodule formation (NF) in a dose-dependent fashion (C-phase). In contrast, addition of PTH(1-34) in late stage cultures (from day 10 to 21) accelerated NF (A-phase). The stable production of such an A-phase allowed us to study the mechanism of bone anabolic action of PTH(1-34). Subcellular localization studies of core binding factor alpha1 (Cbfa1) and reporter assays provided the results indicating that in the A-phase, PTH(1-34) triggers its bone anabolic action via enhancement of Cbfa1 transactivation. RT-PCR and Northern blot analyses revealed that alkaline phosphatase, osteocalcin and bone sialoprotein expression decreased in the C-phase and increased in the A-phase; however, expression of other bone proteins (Cbfa1, PTH/PTH-related peptide-receptor, osteopontin, collagen I alpha1, collagen I alpha2, vitamin K-dependent gamma-glutamyl carboxylase) did not change in a phase transition-related manner. Ovariectomized osteopenic mice, treated with PTH(1-34) (4 and 40 microg/kg, s.c., every other day, 4 or 6 weeks), recovered lost bone, displayed elevated nuclear localization of Cbfal in tibiae without alteration of its cytosolic level and exhibited upregulation of expressions of the same set of proteins (alkaline phosphatase, osteocalcin and bone sialoprotein) in femora. These results obtained by a concerted study in vitro and in vivo suggest that PTH triggers its osteogenic action via promotion of the transactivation of Cbfa1.  相似文献   
995.
A new analogue of vicenistatin was isolated from the producing strain Streptomyces sp. HC-34. A characteristic of the elucidated structure involved the existence of a neutral sugar mycarose instead of an aminosugar vicenisamine of vicenistatin. The absolute stereochemistry of the new analogue (named as vicenistatin M) was determined by the synthesis of D-mycarose and of vicenistatin M itself. Biological testing of vicenistatin M suggested the importance of vicenisamine for exerting the cytotoxicity of vicenistatin.  相似文献   
996.
Although total gastrectomy with distal pancreatectomy has been the standard surgical treatment for advanced gastric cancer, this procedure is frequently complicated by leakage of pancreatic juice and postoperative diabetes mellitus. We present the case of a 74-year-old woman with proximal gastric cancer who underwent a laparoscopic modification of an open pancreas-preserving procedure first described by Maruyama et al. in 1995. With this novel technique, there is no pancreatic leakage, and at 12-month follow-up our patient remains free of diabetes. Herein we give the details of our new method and offer some caveats for its performance.  相似文献   
997.
We report a case of anaphylactic reaction occurring during general anesthesia that may have been accompanied by a coronary artery spasm. The present case and a review of the medical literature suggest that coronary artery spasm is evoked by common vasoactive mediators with anaphylactic reactions. Coronary artery spasm should be counted as a symptom of the cardiovascular manifestation of anaphylaxis. Clinicians should be aware of this possible complication when treating an anaphylactic reaction, especially in patients at risk for atherosclerosis. Early recognition of ST segment elevation is essential for diagnosis and treatment of coronary artery spasm.  相似文献   
998.
BACKGROUND: Clusterin is a soluble complement regulatory protein that binds to C5b-7 and inhibits generation of membrane attack complex, C5b-9. Glomerular deposition of clusterin has been observed in human and experimental membranous nephropathy in association with C5b-9 and immune deposits. However, it is controversial as to whether clusterin observed in glomeruli is synthesized by the resident glomerular cells or is derived from the circulation. We examined whether clusterin is expressed by resident glomerular cells exposed to complement-mediated injury. METHODS: In vitro, cultured mesangial cells were exposed to antithymocyte serum immunoglobulin G and 5% normal rat serum as a complement source. In vivo, we induced anti-Thy1 nephritis in rats and examined the kidneys on days 8 and 29. RESULTS: We observed increased expression of clusterin in cultured rat glomerular mesangial cells stimulated by sublytic complement attack. We also demonstrated that in comparison with control rats, both a marked increase in clusterin mRNA in the glomeruli and marked deposition of clusterin protein in the mesangial area occurred in the OX-7-treated rats on day 8 in association with C5b-9 deposition and on day 29. CONCLUSION: Clusterin was induced in glomerular mesangial cells during the course of immune-mediated injuries. This up-regulation of clusterin may play a critical role in protecting mesangial cells from complement attack.  相似文献   
999.
Weaning of immunosuppression in living donor liver transplant recipients   总被引:15,自引:0,他引:15  
BACKGROUND: Some reported studies have indicated the possibility of immunosuppression withdrawal in cadaveric liver transplantation. The aim of this study was to evaluate the possibility and feasibility of weaning living donor liver transplant recipients from immunosuppression. METHODS: From June of 1990 to October of 1999, 63 patients were considered to be weaned from immunosuppression. They consisted of 26 electively weaned patients and 37 either forcibly or incidentally weaned patients (nonelective weaning) due to various causes but mainly due to infection. Regarding elective weaning, we gradually reduced the frequency of tacrolimus administration for patients who survived more than 2 years after transplantation, maintained a good graft function, and had no rejection episodes in the preceding 12 months. The frequency of administration was reduced from the conventional b.i.d. until the start of weaning to q.d., 4 times a week, 3 times a week, twice a week, once a week, twice a month, once a month, and finally, the patients were completely weaned off with each weaning period lasting from 3 to 6 months. The reduction method of nonelective weaning depended on the clinical course of each individual case. When the patients were clinically diagnosed to develop rejection during weaning, then such patients were treated by a reintroduction of tacrolimus or an additional steroid bolus when indicated. RESULTS: Twenty-four patients (38.1%) achieved a complete withdrawal of tacrolimus with a median drug-free period of 23.5 months (range, 3-69 months). Twenty-three patients (36.5%) are still being weaned at various stages. Sixteen patients (25.4%) encountered rejection while weaning at median period of 9.5 months (range, 1-63 months) from the start of weaning. All 16 were easily treated with the reintroduction of tacrolimus or additional steroid bolus therapy. CONCLUSIONS: We were able to achieve a complete withdrawal of immunosuppression in some selected patients. Although the mechanism of graft acceptance in these patients has yet to be elucidated, we believe that a majority of long-term patients undergoing living donor liver transplantation may, thus, be potential candidates to be successfully weaned from immunosuppression.  相似文献   
1000.
The authors present the 16th case of a pseudoaneurysm forming at the site of an infected radial artery catheter and only the third case that presented with rupture and hemorrhage requiring emergent operative repair. Radial artery catheters are quite safe, and most infections can be treated effectively with line removal and intravenous antibiotics. However, two factors correlate strongly with the subsequent development of pseudoaneurysms. Infection with Staphylococcus aureus was seen in 15 of 16 cases, and persistent signs of infection lasting more than 48 hours after the institution of antibiotic therapy and line removal were seen in 16 of 16 cases. Therefore, patients with S. aureus radial artery line infections with persistence of infection more than 48 hours after the induction of treatment are at high risk and should be observed closely for signs of pseudoaneurysm formation. Once a pseudoaneurysm has formed, surgical repair is required. Most recommend ligating the artery if there is pulsatile backbleeding from the distal stump and Allen's test shows good perfusion of the hand by the ulnar artery.  相似文献   
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