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61.
Purpose Our purpose was to study the characteristics of colorectal neoplasms in patients with gastric cancer (GC). Methods The study group comprised GC patients who underwent colonoscopy before resection of their GC. We examined the prevalence, site, and histology of colorectal neoplasms, as well as the clinicopathological features and treatment of the patients who had synchronous colorectal cancers (CRC). The logistic regression model was applied to investigate the features of the GC patients with concurrent CRC. Results We studied 466 GC patients (mean age 64.5 years; 147 women, 319 men), 143 (31%) of whom had a family history of gastrointestinal cancer. Synchronous colorectal adenoma and cancer were detected in 182 (39%) and 18 (4%) patients, respectively. Among the 18 synchronous CRCs, 11 were in the early stages and 10 of these were resected endoscopically. The other eight required simultaneous open radical surgery. All the GC patients with synchronous CRC were older than 50 years. Statistical analysis did not show a significant difference between the features of the patients with and those without concurrent CRC. Conclusions The possibility of synchronous colorectal neoplasms in GC patients cannot be disregarded in clinical practice; however, screening of the large bowel may not be necessary in GC patients younger than 50 years.  相似文献   
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63.
We investigated the possibility of articular cartil-age distraction for use in reconstructing joint structure and for increasing the donor site of osteochondral grafts. Intraarticular osteotomy was performed at the femoral condyle in 12 Japanese white rabbits. The bone segment was fixed with a specially designed external fixator. After a 3-week waiting period, distraction was performed intermittently for 3 weeks (0.7 mm × 3 times per week) in the distraction group (n = 7) and, in the remaining animals (gap group; n = 5), a gap of 6.3 mm in length was made at surgery. All rabbits received etidronate injections (20 mg/kg ×2 times per week) for 5 weeks, to slow mineralization. The femoral condyle was harvested 9 weeks postoperatively and decalcified sagittal sections were stained and evaluated, using a histological grading scale. In the distraction group, distraction of 4.2 ± 1.4 mm was achieved, and the distracted cartilage area was filled with regenerated cartilage, without any gap between the regenerated and the adjacent articular cartilage. This regenerated cartilage showed metachromasia with toluidine blue. In the gap group, newly formed cartilage tissue was folded from the edge of the osteotomy site and fibrous tissue was interposed in the gap. The histological grading score was significantly lower in the distraction group (P < 0.02). Our preliminary results demonstrated the possibility of cartilage distraction; however, long-term observation will be necessary to confirm the characteristics of the distracted cartilage. We may call the process "distraction arthrogenesis", because the entire articular entity, which consists of cartilage, subchondral bone, and bone, could be distracted at once. Received: April 5, 2001 / Accepted: July 15, 2001  相似文献   
64.
Interventional embolization is currently the first line treatment for arteriovenous fistulas; however, the efficacy of repeated embolization remains controversial. A case is reported of an idiopathic renal arteriovenous fistula with large aneurysmal dilatation treated by surgery following the failure of interventional embolization. A 42-year-old woman was admitted to Ichikawa General Hospital, Japan, with gross hematuria containing many clots. Right renal arteriogram showed an aberrant vessel arising from the main trunk of the renal artery, which was followed by the formation of an aneurysm and rapidly ended in arteriovenous shunting. The aneurysm was approximately 35 mm in size. As interventional embolization had failed, surgical treatment including extracorporeal renal surgery was performed. Postoperative renal angiography revealed excellent renal function and beautiful vascular architecture. Although the indication for surgical treatment of renal vascular disease has decreased owing to the advancement of interventional techniques, there are still some risky cases for which surgical repair should be recommended.  相似文献   
65.
Heart transplantation is the most effective therapy for end-stage heart failure in patients with diabetes mellitus (DM). However, diabetes-related complications (DRCs) are a relative contraindication for heart transplantation. Nevertheless, the increasing prevalence of both DM and congestive heart failure makes it necessary to perform heart transplantation even in those patients with advanced DM. We performed a retrospective analysis on long-term survival in 47 patients with insulin-treated DM and DRCs (group 1). Survival rate and causes of death were compared with data of a group of heart transplant recipients without DM (n = 1061, group 2). Mean follow-up time of all heart transplant recipients was 68.2 months (range: 0-204 months). Overall mortality during follow-up was 42.9%. Long-term survival did not differ significantly between study groups, but tended to be shorter in group 1 than in group 2 (P = 0.07). In group 1, steroid-free immunosuppressive therapy was associated with a higher percentage of long-term survivors compared with no steroid-free immunosuppression. Our data demonstrate that long-term survival is acceptable in heart transplant recipients with preoperatively diagnosed DM and DRCs. Consequently, advanced DM should no longer be a relative contraindication for heart transplantation.  相似文献   
66.
67.
Bone marrow chimerism and tolerance induced by single-dose cyclophosphamide   总被引:3,自引:0,他引:3  
BACKGROUND: Establishment of hematopoietic chimerism is the most stable strategy for donor-specific tolerance. Safer pretreatment regimens are needed for clinical application. We evaluated the efficacy of a simple protocol using cyclophosphamide (CYP) on induction of chimerism and organ transplant tolerance across major histocompatibility complex (MHC) barriers in the rat. MATERIALS AND METHODS: Bone marrow cells from BN (RT1(n)) donors were infused to LEW (RT1(l)) recipients on day 0 after a single injection of CYP at various doses on day -1. Donor-derived hematopoietic chimerism was evaluated by flowcytometry. The recipients received BN or third party (BUF) heart allografts on day 100. RESULTS: While pretreatment with 200 mg/kg of CYP induced high levels of hematopoietic chimerism, six of eight recipients died of severe graft-versus-host-disease (GVHD). CYP at dose of 150 mg/kg induced 36.5 +/- 24.1% of donor-derived chimerism on day 10, and sustained macrochimerism was seen until day 100 without GVHD. Pretreatment with 100 mg/kg of CYP resulted in only transient chimerism (4.8 +/- 5.2%) which disappeared by day 20. In the recipients with 50 mg/kg of CYP, donor bone marrow cells were rapidly rejected and no chimerism was observed. The recipients with 150 mg/kg of CYP accepted BN heart allografts (>100 days x 5), while rejecting BUF allografts by day 12 (n = 4). BN heart allografts were rejected in the recipients with 100 (MST: 57 days, n = 5) and 50 mg/kg (MST: 7 days, n = 5) of CYP. CONCLUSIONS: A single dose of CYP can induce hematopoietic chimerism across MHC-barriers. The dose of 150 mg/kg seems to be optimal to induce organ transplant tolerance without developing GVHD.  相似文献   
68.
We developed an easy method of measuring the presampling modulation transfer function (MTF) using the square wave chart in digital radiography. In this method, the presampling MTF is measured by Fourier transform of image data of the square wave chart. When Fourier analysis of the sampling data of a square wave is carried out, it is generally difficult to find the starting point and terminal point of the periodic data that should be extracted because of an insufficient number of data. To solve this problem, interpolated data were calculated by using a window function of the frequency domain. The aliasing error was avoided using a characteristic such that the square wave has discrete frequency components. The accuracy of this method was investigated by computer simulation study. Actual measurement of the presampling MTF by this method was also performed with a CR system. These studies indicated the effectiveness of our proposed method in terms of accuracy and ease of use.  相似文献   
69.
The effects of dietary potassium on the hemodynamics and plasma norepinephrine (NE) kinetics were studied in 10 patients with borderline hypertension. Potassium supplement (96 mEq daily for 5-7 days) induced a significant (p less than 0.05) fall in blood pressure and a slight decrease in cardiac output. Both urine volume and urinary sodium excretion increased significantly (p less than 0.05) for a first few days following the potassium supplement. The baseline values of the half-time of the rapid NE removal from plasma was significantly delayed in the hypertensive patients (1.05 +/- 0.06 min, p less than 0.05) when compared with those (0.88 +/- 0.04) in normal controls. Potassium supplement induced a significant rise in both plasma NE levels and NE outflow rate (p less than 0.01) in the hypertensive patients, while their half-times were significantly shortened (0.89 +/- 0.07 min, p less than 0.01). The pressor responsiveness to exogenously infused NE tended to diminish during the potassium supplement. These findings indicate that a high potassium intake might accelerate the slowed neuronal NE uptake in the hypertensive patients, while a potassium-induced fall in blood pressure might exert a baroreflex stimulation of NE release. As a net result, an increased NE outflow into the circulation has been confirmed. It is likely that a natriuresis-induced volume contraction might be a predominant factor responsible for the early reduction of blood pressure during the high potassium intake.  相似文献   
70.

Background

Despite the development of the surgical technique and improvements in perioperative management, anastomotic leakage still occurs at esophagojejunal anastomoses after total or proximal gastrectomy. Anastomotic leakage is one of the major complications of concern, chiefly because it can lead to death. The objective of the present study was to identify the risk factors for esophagojejunal anastomotic leakage.

Methods

The study was based on retrospective analysis of the data of a total of 1,640 consecutive patients who underwent total, proximal, or completion gastrectomy, including esophagojejunal anastomosis, between 1999 and 2008.

Results

Thirty-five patients (2.1 %) developed anastomotic leakage. Univariate analysis revealed patient age, pulmonary insufficiency, lymph node dissection, combined resection of other organs, omental resection, operative time, blood loss, intraoperative blood transfusion, and postoperative creatinine level were the significant factors influencing anastomotic leakage. Multivariate analysis identified pulmonary insufficiency and the duration of the operation as the predictors of anastomotic leakage.

Conclusions

To avoid leakage, surgeons should take care in creating the anastomosis in gastrectomy patients, particularly in cases of poor pulmonary function or when the procedure requires a longer operation.  相似文献   
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