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91.
Obesity Surgery - Previous studies have shown that bariatric surgery reduces the risk of cardiovascular outcomes. Less is known about the effects of bariatric surgery on psychiatric disorders. This...  相似文献   
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Background

To develop a risk scoring system (RSS) to determine recurrence in women with early-stage type 1 endometrial cancer (EC).

Methods

Data of 396 women with early-stage type 1 EC who received primary surgical treatment between January 2001 and December 2012 were abstracted from multicentre database (training set). A risk model for predicting recurrence was developed and internally validated with the bootstrap technique. The RSS was externally validated using data from an independent population.

Results

Overall, the recurrence rate was 12.1 %. The median follow-up and initial time to recurrence were 34 (range 1–152) and 26 (range 1–151) months, respectively. Recurrence was associated with five variables: age ≥60 years, histological grade III, primary tumor diameter >2 cm, depth of myometrial invasion ≥50 %, and the positive lymphovascular space involvement status. These variables were included in the RSS and assigned scores. A total score of 6.5 points corresponded to the optimal threshold of the RSS. For women with a score <6.5 or ≥6.5, the recurrence rates were 8.4 % (30/357) and 48.7 % (19/39) in the training set, respectively. At this threshold, the diagnostic accuracy of the RSS was 87 %. Areas under the curve of the receiver-operating characteristics for predicting recurrence at internal and external validation were 0.74 [95 % confidence interval (CI) 0.71–0.77] and 0.82 (95 % CI 79–85), respectively.

Conclusions

This RSS identified two subsets of women with low and high risk of recurrence among women with early-stage type 1 EC. It could be helpful to better define indications for nodal staging and adjuvant therapy.  相似文献   
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The use of adhesively bonded carbon fiber reinforced polymer (CFRP) materials to reinforce cracked steel elements has gained widespread acceptance in order to extend the lifespan of metallic structures. This allows an important reduction of the stress intensity factor (SIF) at the crack tip and thus a significant increase of the fatigue life. This paper deals with the assessment of the SIF for repaired cracked steel plates, using semi-empirical analysis and finite element analysis. Metallic plates with only one crack originating from a center hole were investigated. Virtual crack closure technique (VCCT) was used to define and evaluate the stress intensity factor at crack tip. The obtained modeling results are compared with experimental investigations led by the authors for different reinforcement configurations including symmetrical and non-symmetrical reinforcement, normal modulus and ultra-high-modulus CFRP plates, and pre-stressed CFRP plates. Results show that finite element model (FEM) analysis can obviously simulate the fatigue performance of the CFRP bonded steel plates with different reinforcement configurations. Moreover, a parametric analysis of the influence of the pre-stressing level was also conducted. The results show that an increase of the pre-stressing level results in an increase of the fatigue life of the element.  相似文献   
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Background: The hepatic hemodynamics is an essential parameter in surgical planning as well as in various disease processes. The transit time ultrasound(TTUS) perivascular flow probe technology is widely used in clinical practice to evaluate the hepatic inflow, yet invasive. The phase-contrast-MRI(PC-MRI) is not invasive and potentially applicable in assessing the hepatic blood flow. In the present study, we compared the hepatic inflow rates using the PC-MRI and the TTUS probe, and evaluated their predictive value of post-hepatectomy adverse events. Methods: Eighteen large white pigs were anaesthetized for PC-MRI and approximately 75% hepatic resection was performed under a unified protocol. The blood flow was measured in the hepatic artery(Qha), the portal vein(Qpv), and the aorta above the celiac trunk(Qca) using PC-MRI, and was compared to the TTUS probe. The Bland-Altman method was conducted and a partial least squares regression(PLS) model was implemented. Results: The mean Qpv measured in PC-MRI was 0.55 ± 0.12 L/min, and in the TTUS probe was 0.74 ± 0.17 L/min. Qca was 1.40 ± 0.47 L/min in the PC-MRI and 2.00 ± 0.60 L/min in the TTUS probe. Qha was 0.17 ± 0.10 L/min in the PC-MRI, and 0.13 ± 0.06 L/min in the TTUS probe. The Bland-Altman method revealed that the estimated bias of Qca in the PC-MRI was 32%(95% CI:-49% to 15%); Qha 17%(95% CI:-15% to 51%); and Qpv 40%(95% CI:-62% to 18%). The TTUS probe had a higher weight in predicting adverse outcomes after 75% resection compared to the PC-MRI( β= 0.35 and 0.43 vs β = 0.22 and 0.07, for tissue changes and premature death, respectively). Conclusions: There is a tendency of the PC-MRI to underestimate the flow measured by the TTUS probes. The TTUS probe measures are more predictive of relevant post-hepatectomy outcomes.  相似文献   
98.
Fractalkine is the only member of the CX3C chemokine family. Polymorphism of the fractalkine receptor gene may influence the prognosis of human immunodeficiency virus (HIV) infection, but the nature of the cells expressing fractalkine or its receptor in HIV-infected patients remains unknown. We show that, in contrast to HIV-uninfected individuals, a large number of cells expressed fractalkine in T-cell zones of lymph nodes from HIV-infected patients. CD83(+) mature and CD123(+) plasmacytoid dendritic cells as well as plasma cells are involved in this increased expression of fractalkine. Increased numbers of plasmacytoid dendritic cells and plasma cells were present in T-cell zones of HIV-infected patients. CD83(+) dendritic cells were present in similar number in HIV-infected patients and controls, but an increased fraction of these cells produced fractalkine in HIV-infected patients. Many plasma cells in the gut-associated lymphoid tissue from HIV-infected patients also produced fractalkine, whereas few cells produced fractalkine in the gut of controls. The fraction of CD45RO(+) and CD45RO(-) T helper (Th) cells expressing the fractalkine receptor CX3CR1 was higher in HIV-infected patients than in healthy individuals, and these cells were abnormally sensitive to fractalkine stimulation. This increased response correlated with HIV viremia, and it returned to normal levels in patients successfully treated with antiretroviral drugs. The increased expression of the fractalkine/fractalkine receptor complex associated with HIV infection may affect adhesion and migration of Th lymphocytes and their interaction with dendritic cells. Thus, it may influence the equilibrium between depletion and renewal of the Th lymphocyte compartment.  相似文献   
99.

Background

Turnbull–Cutait abdominoperineal pull-through followed by delayed coloanal anastomosis (DCA) was first described in 1961. Studies have described its use for challenging colorectal conditions. We reviewed our experience with Turnbull–Cutait DCA as a salvage procedure for complex failure of colorectal anastomosis.

Methods

We performed a retrospective cohort study from October 2010 to September 2011, with analysis of postoperative morbidity and mortality.

Results

Seven DCAs were performed for anastomotic complications (3 chronic leaks, 2 rectovaginal fistulas, 1 colovesical fistula, 1 colonic ischemia) following surgery for rectal cancer. Six patients had a diverting ileostomy constructed as part of previous treatment for anastomotic complications before the salvage procedure. No anastomotic leaks were observed. All procedures but 1 were completed successfully. One patient who underwent DCA subsequently required an abdominoperineal resection and a permanent colostomy for postoperative extensive colonic ischemia. No 30-day mortality occurred.

Conclusion

Salvage Turnbull–Cutait DCA appears to be a safe procedure and could be offered to patients with complex anastomotic complications. This procedure could be added to the surgeon’s armamentarium as an alternative to the creation of a permanent stoma.  相似文献   
100.
The pathogenesis of follicular lymphoma is a multi-hit process progressing over many years through the accumulation of numerous genetic alterations. Besides the hallmark t(14;18), it is still unclear which other oncogenic hits contribute to the early steps of transformation and in which precursor stages these occur. To address this issue, we performed high-resolution comparative genomic hybridization microarrays on laser-capture micro-dissected cases of follicular lymphoma in situ (n=4), partial involvement by follicular lymphoma (n=4), and duodenal follicular lymphoma (n=4), assumed to represent, potentially, the earliest stages in the evolution of follicular lymphoma. Cases of reactive follicular hyperplasia (n=2), uninvolved areas from follicular lymphoma in situ lymph nodes, follicular lymphoma grade 1–2 (n=5) and follicular lymphoma grade 3A (n=5) were used as controls. Surprisingly, alterations involving several relevant (onco)genes were found in all entities, but at significantly lower proportions than in overt follicular lymphoma. While the number of alterations clearly assigns all these entities as precursors, the pattern of partial involvement by follicular lymphoma alterations was quantitatively and qualitatively closer to that of follicular lymphoma, indicating significant selective pressure in line with its faster rate of progression. Among the most notable alterations, we observed and validated deletions of 1p36 and gains of the 7p and 12q chromosomes and related oncogenes, which include some of the most recurrent oncogenic alterations in overt follicular lymphoma (TNFRSF14, EZH2, MLL2). By further delineating distinctive and hierarchical molecular and genetic features of early follicular lymphoma entities, our analysis underlines the importance of applying appropriate criteria for the differential diagnosis. It also provides a first set of candidates likely to be involved in the cascade of hits that pave the path of the various progression phases to follicular lymphoma development.  相似文献   
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