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941.
942.

Background  

Liver transplantation plays an important role in the multimodal treatment options for patients with hepatocellular carcinoma (HCC). However, there has been little information about the prognosis for HCC recurrence after living donor liver transplantation (LDLT).  相似文献   
943.
Bone marrow‐derived stromal cells (BMSCs) contain mesenchymal stem cells that are capable of forming various mesenchymal tissues. We hypothesized that BMSCs and β‐tricalcium phosphate (β‐TCP) composites would promote the remodeling of large‐sized autologous devitalized bone grafts; therefore, the aim of this study was to evaluate the effects of the composites on the remodeling of autologous devitalized bone grafts. Autologous BMSCs cultured in culture medium containing dexamethasone (10?7 M) were loaded into porous β‐TCP granules under low‐pressure. Theses BMSC/TCP composites were put into the bone marrow cavity of autologous heat‐treated bone (femoral diaphysis, 65‐mm long, 100°C, 30 min) and put back to the harvest site. In the contralateral side, β‐TCP without BMSC were used in the same manner as the opposite side as the control. Treatment with the BMSC/TCP composites resulted in a significant increase in thickness, bone mineral density, and matured bone volume of the cortical bone at the center of the graft compared to the control. Histological analysis showed matured regenerated bone in the BMSC loaded group. These results indicate that BMSC/TCP composites facilitated bone regeneration and maturation at the graft site of large‐sized devitalized bone. This method could potentially be applied for clinical use in the reconstruction of large bone defects such as those associated with bone tumors. © 2013 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 31:1308–1316, 2013
  相似文献   
944.
945.
Background. Renal hypouricemia is an autosomal recessive disorder resulting from inactivating mutations in the urate transporter 1 (URAT1) encoded by SLC22A12. To date, 10 mutations have been identified and W258X in the URAT1 gene is the predominant cause in middle to southwestern Japan. However, it is still unclear whether there is a regional specific distribution of mutations in northern Japan. In this study, we analyzed mutations in the URAT1 gene of five Japanese patients with renal hypouricemia in northern Japan. Methods. Peripheral blood mononuclear cells were isolated from patients with hypouricemia and healthy control subjects. A mutation analysis of the URAT1 gene was performed completely by direct automated sequencing of polymerase chain reaction-amplified DNA products. Results. We identified two mutations. These mutations [c.269G>A (R90H) and c.774G>A (W258X)] have been reported in Japanese patients. Two of five patients were homozygotes (W258X), two carried single heterozygous mutations (W258X), and the remaining one was a compound heterozygote (R90H and W258X). Conclusions. Our study suggests that there is no regional different distribution of the URAT1 genetic mutations in Japanese with renal hypouricemia.  相似文献   
946.

Background

This study was designed to determine the surgical outcomes of gastric cancer in elderly patients. This information can help establish appropriate treatment for these patients.

Methods

A total of 1,193 patients with gastric cancer who underwent gastrectomy between 1995 and 2010 were enrolled in this retrospective study. The clinicopathologic features of 104 elderly patients (aged ≥80 years) were compared with those of 1,089 nonelderly patients.

Results

(1) Tumors located in the lower-third of the stomach, differentiated cancer, and surgery with limited lymph node dissection were more common in elderly patients. However, there was no difference in the proportion of laparoscopic gastrectomy between elderly and nonelderly patients. (2) Although surgical complication rates were similar in the two groups, the operative mortality rate was higher in elderly patients (1.9 %) than in nonelderly patients (0.7 %). (3) Elderly patients had a significantly poorer overall survival rate, whereas the disease-specific survival rates of the two groups were similar. Limited lymph node dissection did not influence the disease-specific survival rate of elderly patients. (4) The median life expectancy of elderly gastric cancer survivors was 9.8 years in patients aged 80–84 years and 6.0 years in those ≥85 years. The patients with limited lymph node dissection had slightly better prognosis.

Conclusions

The treatment results in elderly patients were comparable to those in nonelderly patients. These findings suggest that R0 resection with at least limited lymph node dissection according to Japanese guidelines should be considered, even for elderly patients.  相似文献   
947.

Objective

This retrospective study aimed to determine the effect of simultaneous aortic valve replacement (AVR) and coronary artery bypass grafting (CABG) on operative outcomes and long-term survival in elderly patients with a high prevalence of comorbidity.

Methods

One hundred and fifty-seven elderly patients (70 years old or older) undergoing isolated AVR (n = 120) or combined AVR/CABG (n = 37) were evaluated. Operative outcomes were compared between the two surgical groups. Long-term survival was also compared between the groups using the Kaplan–Meier method and long-rank (Mantel–Cox) test.

Results

Operative mortality was 0.8 % for the isolated AVR group and 5.4 % for the combined AVR/CABG group (p = 0.076). The length of the intensive care unit stay for the combined AVR/CABG group was significantly longer than that for the isolated AVR group (median: 40 vs. 21 h, p = 0.008). However, the occurrence rate of hospital complications, such as reoperation for bleeding, deep sternal infection, supra-ventricular arrhythmia, and neurological complications, was similar between the two groups. Actuarial survival at 3 and 5 years was 82.3 and 80.9 % for the isolated AVR group, and 88.3 and 73.0 % for the combined AVR/CABG group, respectively (p = 0.637).

Conclusions

The satisfactory operative and long-term results in our study support a more aggressive simultaneous coronary revascularization combined with AVR for aortic valve stenosis in elderly patients.  相似文献   
948.

Background

Knee osteoarthritis (OA) is a multifactorial disease and strongly affected by mechanical factors. The aims of the present study were to assess validity and reliability of a new muscle strength measuring device, the Quadriceps Training Machine (QTM) and evaluate the relationship between quadriceps strength measured by QTM and radiographic knee OA by epidemiological survey.

Methods

The isometric knee extension muscle strength of QTM was compared with BIODEX in 24 healthy adults. Then, the relationship between radiographic knee OA and quadriceps strength using QTM was investigated with 2,032 knees in 1,016 subjects by an epidemiological survey (Matsudai Knee Osteoarthritis Survey).

Results

Significant correlation was observed between QTM and BIODEX (r = 0.69, 0.82). In the Matsudai Knee Osteoarthritis Survey, the prevalence of radiographic OA (grade II or higher upon Kellgren–Lawrence classification) was: 13, 36.9, 67.8, and 86.5 %, regarding women in their fifties, sixties, seventies, and eighties, respectively, and was 1.7, 13.4, 33.5, and 66.2 % regarding men, respectively. Quadriceps muscle strength declined following 50 years of age, and significant decline was observed in the their sixties and seventies. Quadriceps muscle strength of the OA group (grades II, III and IV) was significantly declined compared with that of the Non-OA group (grade-0 and I). Furthermore, the tendency of the muscle strength level to decline with the progression of knee OA grade was particularly observed between grade 0 and grade I in both men and women and between grade I and grade II in men.

Conclusion

The relationship between radiographic knee OA and quadriceps strength was quantitatively evaluated by an epidemiological survey, and we found a correlation between knee OA and the decline in quadriceps strength. Furthermore, it was suggested that the decline in quadriceps muscle strength may be more strongly related to the incidence of knee OA than to its progression.  相似文献   
949.
Seventy-two-kd heat-shock protein (HSP72) is one of the stress markers induced in cells under stress, such as in the case of ischaemia. Recent studies have suggested that HSP72 is a 'molecular chaperone' to protect cells from various kinds of stress, and that the temporal profile of HSP72 induction is related to ischaemic vulnerability. In this study, we attempted to analyse the temporal profiles of HSP72 induction in epithelial and adipose cells in skin flaps after various periods of transient ischaemia, and we investigated the reason why there were differences in ischaemic tolerance between these cells. We used the abdominal skin flap of Wister rats, which were divided into three groups: the sham control group (n=27), the 2-h ischaemia group (n=25), and the 8-h ischaemia group (n=25). At periods of 8, 24, 48, 96 h, and 7 days after reperfusion, we examined them for any histological changes and performed immunostaining for HSP72 (n=5, each time point). Two animals in the sham control group were sacrificed to harvest the samples immediately after the skin flaps were elevated. As a result, the epithelial cells in all groups revealed positive for HSP72 through the time course, regardless of the ischaemic stresses, and they were alive at 7 days. In the adipose cells, the cells in the sham control group revealed no immunoreactivity after the reperfusion, and they had no change at 7 days. In the 2-h ischaemia group, the adipose cells gradually increased the reactivity for HSP72; consequently they survived beyond 7 days. In the 8-h ischaemia group, the reactivity for HSP72 gradually decreased; consequently they played out a delayed cell death at 7 days. We concluded that these differences of HSP72 expression were related to the cellular vulnerability to ischaemia.  相似文献   
950.
BACKGROUND: The bronchopleural fistula (BPF) is a major complication after lung surgery. We have reviewed our experience with ischemic changes in bronchial stumps, some of which resulted in BPFs (we term this postoperative ischemic bronchitis (POIB)) and studied predisposing factors. METHODS: A total of 1015 patients undergoing curative resection of lung cancers between 1991 and 2002 were reviewed. Details regarding bronchofiberscopic findings within the first 15 postoperative days were carefully reviewed with particular attention to factors possibly affecting the occurrence of POIB: the techniques for bronchial closure and mediastinal lymph node dissection (LND). Information about clinical profiles and histologic status was also analyzed. RESULTS: The incidence of POIB was 2.5% (29/1015), affecting 26 males and 3 females. The most common site was the right intermediate trunk stump (n=4; 7.1%), followed by the left upper (n=8; 3.4%), right lower (n=5; 3.4%), right middle (n=2; 3.3%), and left lower (n=4; 3.2%) lobar bronchial stumps. BPFs eventually resulted in 3 patients (10%) out of 29 with POIB and in 4 (0.4%) out of 986 without it (p<0.0001). Being male, a smoker, having diabetes mellitus, having postoperative respiratory complications and subcarinal LND proved to exert a significant impact with regard to POIB. CONCLUSIONS: Surgeons must bear in mind the possibility of POIB occurrence, especially in cases undergoing particular types of lobectomy (right middle and lower, left upper, right lower or right middle) accompanied by subcarinal LND and having postoperative respiratory complications. Moreover, in appropriate groups with tumors of the right upper lobe or left upper segment, limited mediastinal LND might allow avoidance of POIB.  相似文献   
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