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11.
Annals of Nuclear Medicine - To evaluate the diagnostic performance of 18F-FDG PET/CT in the detection of stent graft infection (SGI). In a retrospective study, two nuclear medicine physicians have...  相似文献   
12.
This study investigates the relationship between blood group and waiting time until transplantation or death on the waiting list. All patients listed for liver transplantation in the Netherlands between 15 December 2006 and 31 December 2012, were included. Study variables were gender, age, year of listing, diagnosis, previous transplantations, blood group, urgency, and MELD score. Using a competing risks analysis, separate cumulative incidence curves were constructed for death on the waiting list and transplantation and used to evaluate outcomes.In 517 listings, the mean death rate per 100 patient‐years was 10.4. A total of 375 (72.5% of all listings) were transplanted. Of all transplantations, 352 (93.9%) were ABO‐identical and 23 (6.1%) ABO‐compatible. The 5‐year cumulative incidence of death was 11.2% (SE 1.4%), and of transplantation 72.5% (SE 2.0%). Patient blood group had no multivariate significant impact on the hazard of dying on the waiting list nor on transplantation. Age, MELD score, and urgency status were significantly related to the death on the waiting list and transplantation. More recent listing had higher probability of being transplanted. In the MELD era, patient blood group status does not have a significant impact on liver transplant waiting list mortality nor on waiting time for transplantation.  相似文献   
13.
The commercial purity of VT1-0 titanium was processed by the rolling process and executed at elevated, room, and cryo-temperatures. These processings led to the formation of an ultrafine-grained microstructure, with the mean grain size at a nanometer level. Some of these materials were statically annealed at a temperature of 823 K for 1 h, which led to significant subgrains and grain coarsening. The constant load creep tests in tension were carried out in argon on all states of materials, at temperatures of 648–723 K and different ranges of applied stresses. From the value of the steady-state creep rate, the control creep mechanisms were determined. The microstructure analyses were carried out via SEM and TEM. It was found that titanium prepared at elevated and room temperatures have a higher creep strength than titanium prepared at cryo-temperatures. Furthermore, the post-SPD —annealing led to a significant decrease in the creep properties. The influence of the preparation temperature on the difference of the creep behavior were discussed and explained using the microstructure analyses of the tests’ samples.  相似文献   
14.
IntroductionBody balance control represents a key factor preventing falls and subsequent injuries in seniors aged 65+. Intervention based on yoga exercises seem to be effective in improving balance.ObjectiveThe objective is to analyse and compare changes in static, dynamic, and total balance scores, changes in body composition and social indices as effects of yoga-based intervention.MethodsA total of 500 participants (234 men aged 74.5 SD±7.74 and 266 women aged 76.9 SD±7.23) were assessed using the Tinetti Balance Assessment Tool, the InBody 230 bioimpedance body composition analyser, and the SF-36 Health Survey, applied to pre and post-testing. The experimental group (n=262; 122 males; 140 females) underwent a four-week yoga-based intervention, 30 minutes daily, while the control group (n=238; 112 males; 126 females) underwent its usual daily programme at senior homes or centres. The ANOVA model, consisting of the Group, Stage, Subject and Group × Stage interaction factors, was used for data evaluation.ResultsIntervention led to improvements in the static, dynamic and total balance scores in the experimental group compared to the control group. The results of SF-36 showed positive changes in the psychosocial aspects of health, such as promoting of calmness and happiness in male seniors and reducing fatigue, nervousness and depression in female seniors. The post-intervention decrease in body fat percentage and increase in muscle mass in seniors is discussed.ConclusionsThe four-week yoga-based intervention had positive effects on the static, dynamic and total balance scores, body composition and social status.  相似文献   
15.
This study aimed to analyze the role of endothelial progenitor cell (EPC)-derived angiogenic factors and chemokines in the multistep process driving angiogenesis with a focus on the recently discovered macrophage migration inhibitory factor (MIF)/chemokine receptor axis. Primary murine and murine embryonic EPCs (eEPCs) were analyzed for the expression of angiogenic/chemokines and components of the MIF/CXC chemokine receptor axis, focusing on the influence of hypoxic versus normoxic stimulation. Hypoxia induced an upregulation of CXCR2 and CXCR4 but not CD74 on EPCs and triggered the secretion of CXCL12, CXCL1, MIF, and vascular endothelial growth factor (VEGF). These factors stimulated the transmigration activity and adhesive capacity of EPCs, with MIF and VEGF exhibiting the strongest effects under hypoxia. MIF-, VEGF-, CXCL12-, and CXCL1-stimulated EPCs enhanced tube formation, with MIF and VEGF exhibiting again the strongest effect following hypoxia. Tube formation following in vivo implantation utilizing angiogenic factor-loaded Matrigel plugs was only promoted by VEGF. Coloading of plugs with eEPCs led to enhanced tube formation only by CXCL12, whereas MIF was the only factor which induced differentiation towards an endothelial and smooth muscle cell (SMC) phenotype, indicating an angiogenic and differentiation capacity in vivo. Surprisingly, CXCL12, a chemoattractant for smooth muscle progenitor cells, inhibited SMC differentiation. We have identified a role for EPC-derived proangiogenic MIF, VEGF and MIF receptors in EPC recruitment following hypoxia, EPC differentiation and subsequent tube and vessel formation, whereas CXCL12, a mediator of early EPC recruitment, does not contribute to the remodeling process. By discerning the contributions of key angiogenic chemokines and EPCs, these findings offer valuable mechanistic insight into mouse models of angiogenesis and help to define the intricate interplay between EPC-derived angiogenic cargo factors, EPCs, and the angiogenic target tissue.  相似文献   
16.
Despite long and intensive research, endometriosis remains one of the leading causes of morbidity among premenopausal women. The majority of endometriosis-related ovarian carcinomas occur in the presence of atypical ovarian endometriosis. Nevertheless, despite the increased incidence of ovarian cancer in patients with endometriosis, our knowledge of the risk factors and mechanisms is still incomplete. Narrative overview, synthesizing the recent findings of literature retrieved from databases. Herein, we reviewed and summarized the most recent knowledge regarding endometriosis and ovarian cancer. The evidence showing that patients with endometriosis have a higher risk of developing ovarian cancer is compelling. However, the question of how much higher the absolute risk is, is not fully clear.  相似文献   
17.
18.
This study describes the facial pillar system in dolichocephalic and brachycephalic breeds of dogs, and highlights its differences. Knowledge of facial pillar system anatomy is imperative to carry out successful fracture repair. The aim of our study was to describe the pillar system of the facial skeleton in dogs, and compare different shapes of dog skulls using native skulls, radiographs and computed tomography (CT). The heads of brachycephalic and dolichocephalic dogs were investigated following a maceration process using trans-illumination, radiography and CT. Ground sections were created from bones of the facial skeleton for investigation of osteon directions. This study has revealed that the facial skeleton of the dog has numerous sinuses supported by vertically and horizontally oriented bone pillars. These pillars can be divided into five principal regions in dolichocephalic skulls and six principal regions in brachycephalic skulls. Radiographic imaging of both the brachiocephalic and dolichocephalic skulls was not capable of discerning bone pillars. Computed tomography transverse and horizontal section images discerned all pillars observed in the illuminated skulls.  相似文献   
19.
Previous studies using reciprocal crosses between the spontaneously hypertensive rat (SHR) and the normotensive Wistar–Kyoto (WKY) strain suggested a role for the Y chromosome in the SHR's exaggerated preference for saline solutions. We have reexamined the role of the Y chromosome in the salt preference of the SHR using a consomic strain derived from SHR and Brown Norway (BN-Lx) progenitors. We also studied congenic lines in which regions of BN-Lx chromosomes 8 and 20 had been introgressed into the SHR genome. Animals were given a choice of water and 0.9% saline to drink over a period of 7 days and their total fluid intake (TFI; water plus saline) and saline preference (proportion of the TFI taken as saline) calculated. SHR bearing the BN-Lx Y chromosome had a significantly reduced saline preference when compared to progenitor SHR. Evidence was also found for the existence of a region on chromosome 8, which influences fluid intake in the SHR. The causative genes involved in these effects however remain to be determined.  相似文献   
20.
Variability in axillary lymph node dissection for breast cancer   总被引:6,自引:0,他引:6  
BACKGROUND: The axillary nodal status may influence the prognosis and the choice of adjuvant treatment of individual breast cancer patients. The variation in number of reported axillary lymph nodes and its effect on the axillary nodal stage were studied and the implications are discussed. METHODS: Between 1994 and 1997, a total of 4,806 axillary dissections for invasive breast cancers in 4,715 patients were performed in hospitals in the North-Netherlands. The factors associated with the number of reported nodes and the relation of this number with the nodal status and the number of positive nodes were studied. RESULTS: The number of reported nodes varied significantly between pathology laboratories, the median number of nodes ranged from 9 to 15, respectively. The individual hospitals explained even more variability in the number of nodes than pathology laboratories (range in median number 8-15, P < 0.0001). The number of reported nodes increased gradually during the study period. A decreasing trend was observed with older patient age. A higher number of reported nodes was associated with a markedly increased chance of finding tumor positive nodes, especially more than three nodes. The frequency of node positivity increased from 28% if less than six nodes to 54% if >/=20 nodes were examined, the percentage of tumors with >/=4 positive nodes increased from 4 to 31%. Multivariate analysis confirmed these results. CONCLUSIONS: This population-based study showed a large variation in the number of reported lymph nodes between hospitals. A more extensive surgical dissection or histopathological examination of the specimen generally resulted in a higher number of positive nodes. Although the impact of misclassification on adjuvant treatment will have varied, the impact with regard to adjuvant regional radiotherapy may have been considerable.  相似文献   
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