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941.
To evaluate laparoscopy-assisted Billroth-I gastrectomy (LADG), we examined the outcome of its use over the last 10 years. From December 1991 to December 2001, 116 patients with early gastric cancer underwent LADG in the surgical department of Oita Medical University and Koga hospital by the same surgical staffs. An operation record and clinical sheets were reviewed to obtain the operative findings, clinical course, and pathologic findings of resected specimens to evaluate the usefulness of LADG in the management of early gastric cancer. In all LADG procedures, regional lymph nodes dissection (D1+alpha) was successfully performed using laparoscopy. The mean operative duration and blood loss were 234 minutes and 139 mL, respectively. There were only four major complications, including pneumonia, leakage of anastomosis, pancreatic injury, and anastomotic stenosis, but all these cases were successfully treated conservatively. The mean length of postoperative stay was 16.3 +/- 2.5 days. All patients except one, who died not of cancer but of cerebral bleeding, were alive without recurrence or port-site metastasis during mean follow-up period of 45 months. We successfully performed 116 LADG procedures over 10 years. This procedure is recommended for the treatment of patients with early gastric cancer because of the associated good prognosis and several benefits, including less invasiveness and early recovery.  相似文献   
942.
It is well recognized that poor perioperative blood glucose (BG) control can increase the risk of infection, cardiovascular accidents, and even death in patients undergoing cardiac surgery. Since it has been reported that tight BG control (80–110 mg/dL) yields better outcomes in critically ill patients, it became a standard of care to control BG using intravenous insulin infusion in ICU. However, it has been debated in terms of the optimal target range whether a strict control with intensive insulin therapy is better than liberal control. Because strict BG control can often cause hypoglycemia, which in turn increases the hospital mortality. In fact, a meta-analysis of randomized clinical trials concluded that tight BG control was not associated with significantly reduced hospital mortality but was associated with an increased risk of hypoglycemia. According to the current published guidelines, it seems to be optimal to control BG level of 140–180 mg/dL in ICU. In terms of more strict BG control (110–140 mg/dL), it may be appropriate in selected patients as long as this can be achieved without significant hypoglycemia.  相似文献   
943.
The purpose of this paper is to describe our recent experience in performing laparoscopic cholecystectomies of which we performed 1904, from January 1991 to May 1997, at our private hospital, mainly to treat cholecystolithiasis. The patients included 1563 with gallbladder stones (82.0%), 82 with cholecystocholedocholithiasis (4.3%), 104 with adenomyomatosis (5.5%), 132 with polyps (6.9%), and 23 with gallbladder cancer (1.3%). A difficult pericholecystic dissection led to conversion to open surgery in 61 patients. The average operation time was 63 min. Bile duct injury or cystic artery bleeding occurred in 3 patients with acute cholecystitis, and small intestine injury occurred in 1 patient, while bile leakage or a right subphrenic abscess occurred in 6 patients postoperatively. Although this series included 69 patients with previous upper abdominal surgery, 14 with liver cirrhosis, 267 with a nonvisualized gallbladder, and 148 with acute cholecystitis, the overall conversion rate was only 3.2% and morbidity only 0.5%. Although almost all patients with cholelithiasis are now considered potential candidates for a laparoscopic cholecystectomy, difficulties during cholecystectomy have been encountered in patients with acute cholecystitis. Surgeons should thus be fully prepared to convert to open surgery whenever difficulties are encountered, in order to avoid complication.  相似文献   
944.
Mucinous cystadenoma of the appendix is a type of appendiceal mucocele and a rather rare condition usually found incidentally in the course of other abdominal surgery. A previous evaluation of 73 appendiceal mucoceles showed that this disease was often associated with adenocarcinoma and other epithelial atypia. This observation suggested that patients with mucinous cystadenoma of the appendix also have some underlying disorders. However, non-epithelial changes associated with appendiceal mucocele have not been reported so far. In this study, we presented for the first time a mucinous cystadenoma of the appendix associated with muscular and neuromatous hyperplasia.  相似文献   
945.
Background Carcinoma arising in the cardioesophageal junction is a distinct clinical entity compared with tumors located in other regions of the stomach. The prognosis for adenocarcinoma of the upper stomach is considered to be relatively poorer than carcinomas of the more distal stomach. We have therefore investigated patients with carcinoma of the gastric cardia in order to evaluate the underlying cause of this poor prognosis. Materials and Methods Clinicopathologic features and postoperative prognosis of 101 patients with carcinoma of the cardia were evaluated and compared with findings on 1884 patients with tumors in other regions of the stomach. Results Tumors of the cardia had a mean size of 6.8 cm, which was significantly larger than the mean size of 5.9 cm for tumors found in the middle- and lower third of the stomach. The incidence of serosal invasion, lymph node metastasis, and lymphatic and blood vessel invasion was higher in association with adenocarcinoma of the cardia than with adenocarcinoma in remaining parts of the stomach. In the analysis of patients who had undergone curative resection, the 5-year survival rates were 61.6, 79.1, and 82.6% in patients with carcinoma of the cardia, upper one-third, and remaining middle- and lower one-third of the stomach, respectively, and the differences were statistically significant. Multivariate analysis indicated that adenocarcinoma of the gastric cardia is an independent prognostic factor. With regard to the site of recurrence, both lymph node and hematogenous recurrence were observed more frequently in the cardia than in the remaining parts of the stomach. Conclusions Our data indicate that the prognosis of patients with adenocarcinoma of the gastric cardia is extremely poor. To improve their prognosis, new treatments in addition to gastrectomy with extensive lymph node dissection are needed.  相似文献   
946.
Transforming growth factor-1 (TGF-1) has biological functions in various types of cells. However, its roles in the regulation of osteoclast formation and function are unclear. To examine them, we employed a culture system in which unfractionated cells obtained from long bones of 13-day-old mice were cultured on a dentine slice. We found that TGF-1 has a potent inhibitory effect on osteoclastic bone resorption at a dose of 0.2–5 ng/ml. By electron microscopy the osteoclasts appeared to have fewer mitochondria and ruffled borders than those in control cultures. But in the presence of 1,25-dihydroxyvitamin D3, [1,25-(OH)2D3], TGF-1 at a dose of 0.2–1 ng/ml stimulated the formation of osteoclasts from unfractionated bone cell cultures in which preexistent osteoclasts had degenerated. Thus, using stromal cell-free he-mopoietic blast cells, we examined the direct action of TGF-1 on osteoclast precursors. Although TGF-1 inhibited tartrate-resistant acid phosphatase-positive (TRAP) multinucleate cell (MNC) formation induced by 1,25-(OH)2D3, the conditioned medium (CM) of TGF-1-treated MC3T3-E1 cells stimulated such formation. These results suggest that TGF-1 inhibits osteoclastic bone resorption but stimulates osteoclast formation via the action of factor(s) produced by TGF-1-treated osteoblasts in the presence of 1,25-(OH)2D3.  相似文献   
947.
In this experiment, the effect of the administration route-the hepatic artery, portal vein, or systemic circulation-of the immunosuppressive drug 15-deoxyspergualin (DSG) on the suppression of liver allograft rejection is investigated. A 3-day injection of DSG at a dose of 0.32–1.28 mg/kg per day into the systemic circulation of a rat that had received a liver transplant was not effective in prolonging liver graft survival (14.3±2.9 days vs. 14.1±2.5 days for controls). However, the administration of DSG into the portal vein following liver transplantation markedly prolonged survival for up to 24.9±10.0 days. Survival times were prolonged even more when the DSG was administered via the hepatic artery for 3 successive days after liver grafting (30.9±9.6 days). The concentration of DSG in the blood following the one-shot injection of DSG was highest when DSG was administered via the hepatic artery, intermediate when injected into the portal vein, and lowest when injected into the systemic vein. In conclusion, DSG can inhibit liver graft rejection more effectively via the hepatic arterial route than via the portal vein or systemic circulation.  相似文献   
948.
Background/Purpose The molecular pathology of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas has not been well characterized, and there are no reliable markers to predict the presence of associated invasive carcinoma in patients with IPMNs. We investigated the clinicopathologic characteristics of 37 IPMNs and the immunohistochemical findings of these tumors to investigate the malignancy of IPMNs. Methods Between May 1992 and September 2003, 37 patients with IPMNs, 24 with adenoma and 13 with carcinoma, underwent pancreatic resections at Sapporo Medical University Hospital, Japan. In tumor specimens from these patients, we immunohistochemically analyzed the expression of p53 protein, proliferating-cell nuclear antigen (PCNA), vascular endothelial growth factor (VEGF), matrix metalloproteinase-7 (MMP-7), and E-cadherin. Clinical features and follow-up after resection were recorded. Results Aberrant expression of the proteins examined was frequently observed. Namely, there were significant differences in the expression of MMP-7 according to clinicopathological characteristics. Positive expression of MMP-7 was found in all of nine patients with infiltrating ductal pancreatic adenocarcinoma (IDC) and in all of seven patients with invasive intraductal papillary mucinous adenocarcinoma (IC-IPMC); however, 33.3% of patients with noninvasive IPMA, 58.3% of patients with intraductal papillary mucinous adenoma (IPMA), and all normal pancreatic tissues were negative for MMP-7; differences which were statistically significant (P < 0.05). Conclusions Our current results indicate that MMP-7 may play a significant role in the progression of noninvasive to invasive IPMC.  相似文献   
949.
Background  For orthopedic implants, infection is a serious problem. Therefore, we considered an implant with antimicrobial ability can prevent infection. We tried to coat a titanium alloy surface with Novaron, a commercially available inorganic antimicrobial. The purpose of this study was to analyze the differences among the surfaces of materials coated using different processing pressures of the working gas and analysis of the antimicrobial activity. Methods  One of the inorganic antimicrobials Novaron (grade VZ 600) was applied to titanium alloy (Ti6Al4V) plates. This antimicrobial has limited heat resistance, so we used cold spray technology to coat the titanium alloy with it. The principle of cold spray technology is spraying a powder in a high-velocity gas jet, accelerated by adiabatic expansion, against a substrate. Scanning electron microscopy (SEM) and energy dispersive X-ray spectrometry (EDS) were used to analyze the differences among the surfaces of materials coated using different processing pressures of the working gas. The Japanese Industrial Standard (JIS) method (JIS Z2801: 2000) was used to analyze the antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae. Antimicrobial activity was analyzed only for the sample coated at 3.0 MPa. Results  The SEM and EDS results indicated that when the pressure of the working gas was increased, the antimicrobial coated the titanium adequately. This material showed good effects against S. aureus and P. aeruginosa and some effect for K. pneumoniae. Conclusions  Antimicrobial implants represent a preventive method against infection. There is a possibility of using them not only for clean operations but also for operations with suspected bacterial contamination, such as fixation of slight compound fractures.  相似文献   
950.
Somatically acquired mutations in the epidermal growth factor receptor (EGFR) gene in lung cancer are associated with significant clinical responses to gefitinib, a tyrosine kinase inhibitor (TKI) that targets EGFR. In our previous report, 42.2% of adenocarcinoma patients has EGFR mutations, and these mutations were more frequently found in women than in men, in well differentiated tumors than poorly differentiated tumors, and in patients who were never smokers than in patients who were current/former smokers. Retrospectively, we screened the EGFR gene of tumors in 37 NSCLC patients who had been treated with gefitinib. EGFR mutations were found in 22 patients. Gefitinib was effective (CR/PR) in 15 of 22 (68.2%) patients with mutations compared with none of 15 patients without mutations. Patients with EGFR mutations survived for a longer period than without the mutations after initiation of gefitinib treatment (p = 0.0005). Gefitinib was not effective in 3 patients with K-ras mutations. Three of 4 tumors obtained from patients with acquired resistant to gefitinib, had a secondary T790M mutation. No T790M mutation was detected in pretreatment tumors. Molecular targeted therapy using TKI indicates an effective therapy specifically in lung cancer patients with EGFR mutations, and analyses of mechanisms of resistance to TKI are necessary for establishment of tailor-made therapy.  相似文献   
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