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991.
We present three cases of self-expandable metallic stent (SEMS) placement using a balloon enteroscope (BE) and its overtube (OT) for malignant obstruction of surgically reconstructed intestine. A BE is effective for the insertion of an endoscope into the deep bowel. However, SEMS placement is impossible through the working channel, because the working channel of BE is too small and too long for the stent device. Therefore, we used a technique in which the BE is inserted as far as the stenotic area; thereafter, the BE is removed, leaving only the OT, and then the stent is placed by inserting the stent device through the OT. In the present three cases, a modification of this technique resulted in the successful placement of the SEMS for obstruction of surgically reconstructed intestine, and the procedures were performed without serious complications. We consider that the present procedure is extremely effective as a palliative treatment for distal bowel stenosis, such as in the surgically reconstructed intestine.  相似文献   
992.
993.
994.

Background

The aim of this study was to clarify the technical feasibility and oncological efficacy of laparoscopy-assisted gastrectomy (LAG) for gastric cancer compared with open gastrectomy (OG).

Methods

Between April 2002 and March 2008, a series of 623 patients with gastric cancer underwent R0 gastrectomy (314 LAG patients and 309 OG patients). Age, gender, lymph node dissection, and pathological stage were matched by propensity scoring, and 212 patients (106 LAG and 106 OG) were selected for analysis after the exclusion of 40 patients who had proximal gastrectomy. Intraoperative factors, postoperative morbidity, long-term quality of life (QOL), and survival were evaluated. Moreover, these outcomes were also compared between the laparoscopy-assisted total gastrectomy (LATG) and the open total gastrectomy (OTG).

Results

There was no significant difference in preoperative characteristics between the two patient groups. Regarding intraoperative characteristics, blood loss was significantly lower in the LAG group (143?ml) than in the OG group (288?ml), while operation time was significantly longer in the LAG group (273?min) than the OG group (231?min). The degree of lymph node dissection and number of retrieved lymph nodes did not differ between the two groups. There were no significant differences in postoperative courses or overall and disease-specific survival (89.8% vs. 83.6%, P?=?0.0886; 100% vs. 95.2%, P?=?0.1073) except time to first flatus and time to use of nonsteroidal anti-inflammatory derivatives between the two groups. Significantly fewer patients felt wound pain in the LAG group 1?year after surgery. Analyses between the LATG and OTG groups showed similar results.

Conclusions

LAG for gastric cancer may be both feasible and safe. However, it will be necessary to conduct a well-designed randomized controlled trial comparing short-term and long-term outcomes between LAG and OG in a larger number of patients.  相似文献   
995.
Gastric carcinoma is relatively rare in patients under the age of 40. This study was undertaken to clarify the clinicopathological characteristics and surgical outcomes of gastric carcinoma in younger patients compared with those of middle-aged patients. The surgical results from 131 younger patients (aged ⩽40 years) and 918 middle-aged patients (aged 55–65 years) were compared retrospectively. Female gender, undifferentiated tumor type and lymphatic invasion were significantly more common in the younger patients. Survival time did not differ between the two groups. The depth of tumor invasion was the only prognostic factor in younger patients, whereas macroscopic appearance, tumor diameter, depth of invasion, lymph node metastasis, and venous invasion were all significant prognostic factors in middle-aged patients. Peritoneal recurrence was significantly more common in younger patients. A family history of gastric adenocarcinoma was observed in 25.9% of younger patients, but this did not affect survival outcomes. As depth of invasion affects prognosis independently, and peritoneal metastasis is the predominant pattern of recurrence, it is essential to establish an optimal prophylactic treatment for peritoneal metastasis to improve surgical outcomes in younger patients with advanced gastric cancer.  相似文献   
996.

Background Context

There is a lack of information about postoperative outcomes and related risk factors associated with spinal surgery in patients with Parkinson's disease (PD).

Purpose

This study aimed to investigate the postoperative morbidity and mortality associated with spinal surgery for patients with PD, and the risk factors for poor outcomes.

Study Design

This is a retrospective matched-pair cohort study.

Patient Sample

Data of patients who underwent elective spinal surgery between July 2010 and March 2013 were extracted from the Diagnosis Procedure Combination database, a nationwide inpatient database in Japan.

Outcome Measures

In-hospital mortality and occurrence of postoperative complications.

Methods

For each patient with PD, we randomly selected up to four age- and sex-matched controls in the same hospital in the same year. The differences in in-hospital mortality and occurrence of postoperative complications were compared between patients with PD and controls. A multivariable logistic regression model fitted with a generalized estimation equation was used to identify significant predictors of major complications (surgical site infection, sepsis, pulmonary embolism, respiratory complications, cardiac events, stroke, and renal failure). Multiple imputation was used for missing data.

Results

Among 154,278 patients undergoing spinal surgery, 1,423 patients with PD and 5,498 matched controls were identified. Crude in-hospital mortality was higher in patients with PD than in controls (0.8% vs. 0.3%, respectively). The crude proportion of major complications was also higher in patients with PD (9.8% vs. 5.1% in controls). Postoperative delirium was more common in patients with PD (30.3%) than in controls (4.3%). Parkinson's disease was a significant predictor of major postoperative complications, even after adjusting for other risk factors (odds ratio, 1.74; 95% confidence intervals, 1.37–2.22; p<.001).

Conclusions

Patients with PD had a significantly increased risk of postoperative complications following spinal surgery. Postoperative delirium was the most frequently observed complication.  相似文献   
997.
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   
998.
A segment of the transverse colon can be used for gastric reconstruction after a total gastrectomy. This report presents the case of a 68-year-old woman with primary adenocarcinoma of the colon in a segment used for reconstruction after a total gastrectomy. The interposed colon developed colon carcinoma 9 years after the gastric reconstruction. The possibility of a primary carcinoma arising in a gastric colon interposition must be considered when employing the transverse colon as a gastric substitute.  相似文献   
999.

Purpose

We assessed whether a high b-value DWI at b = 4000 s/mm2 would discriminate the histopathological differentiation of the tumor grade of meningiomas, and also focused on the relationship between radiologic features and the tumor grade.

Materials and methods

We acquired DWI at 3T with b = 1000 and b = 4000 s/mm2 in 77 patients (42, 31 and 4 patients were WHO grades I (G1), II (G2), and III (G3), respectively). The apparent diffusion coefficient (ADC) was measured by placing multiple regions of interest (ROIs) on ADC maps. The ADC values of each tumor were determined preoperatively from several ROIs, and expressed as the minimum (ADCMIN), mean (ADCMEAN), and maximum absolute values (ADCMAX). We evaluated the relationship between ADCs and histological findings, and assessed the radiologic features such as tumor location, tumor size, presence/absence of peritumoral edema, shape of the tumor, presence/absence of bone destruction or hyperplasia, status of contrast enhancement, presence/absence of calcification and cyst.

Results

ADCs of the meningiomas were inversely correlated with the histological grade of meningiomas. According to results of the discriminant analysis, the apparent log likelihood value was greatest for ADCMIN at b = 4000. Furthermore, only the ADCMIN value at b = 4000 was significantly correlated with the histological grade of meningiomas when we performed a multiple logistic regression analysis to identify the significant independent factors such as shape of tumor, presence/absence of bone destruction, status of contrast enhancement, presence/absence of cyst and ADCMIN at b = 4000.

Conclusion

A meningioma with a low ADCMIN at a high b-value might imply a high-grade meningioma.  相似文献   
1000.
BACKGROUND: Immune regulatory CD4+CD25+ T (regulatory T; Treg) cells play a vital role in the induction and maintenance of self-tolerance. They are essential for the homeostasis of T cells, the prevention of autoimmunity, and the induction of tolerance to allogeneic donor grafts. However, the underlying mechanism of their functions remains mostly elusive. Therefore, we investigated here a crucial role of Treg cells in their response to alloantigen via the programmed death (PD)-1/PD-1 ligand (PD-L1) pathway. METHODS: In vitro mixed lymphocyte reaction (MLR) assay, graft-versus-host disease (GvHD) and a skin transplantation model were used to evaluate the mechanisms of PD-1/PD-L1 pathway. RESULTS: Blockade of the PD-1/PD-L1 pathway using anti-PD-L1 monoclonal antibodies (mAb) is found to inhibit Treg cell's ability to suppress and restore CD4+CD25-T-cell proliferation in vitro. GvHD was lethal after adoptive transfer of allogeneic C57BL/6 (H-2K) spleen cells to NOD/SCID (H-2K) mice unless CD25+ T cells were also included. Strikingly, the suppression of GvHD by CD25+ cells was abrogated by anti-PD-L1 mAb administration. The abrogation of Treg-cell-mediated suppression could also be demonstrated in a Balb/c (H-2K) to B6/Rag-2KO (H-2K) skin-allograft model. CONCLUSIONS: The blockade of the PD-1/PD-L1 pathway abrogates Treg-mediated immunoregulation, thus suggesting that the PD-1/PD-L1 pathway is required for Treg suppression of the alloreactive responses of CD4+CD25-T cells. This finding has important implications for clarifying the mechanisms of allograft rejection and GvHD.  相似文献   
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