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231.
232.

Background

Whereas the poor prognosis of signet ring cell adenocarcinomas of the appendix is well known, the significance of mucinous histology remains unclear. The aim of this population-based study was to evaluate if mucinous histology is an independent prognostic factor in appendiceal adenocarcinomas.

Methods

Patients with stage I–III adenocarcinoma of the appendix who underwent surgery between 2004 and 2012 were identified in the Surveillance, Epidemiology, and End Results database. Overall survival (OS) and cancer-specific survival (CSS) were assessed using risk-adjusted Cox proportional hazards regression models and propensity score methods.

Results

Overall, 980 patients with appendix cancer were included, of which 449 (45.8 %) had a mucinous histology. In an unadjusted analysis, the 5-year OS and CSS in patients with a mucinous adenocarcinoma (MC) was 76.8 % (95 % confidence interval (95 %CI): 72.1–81.7 %) and 81.0 % (95 %CI: 76.6–85.6 %), respectively, compared with 70.0 % (95 %CI: 65.1–75.3 %) and 76.2 % (95 %CI: 71.5–81.2 %) in patients with non-mucinous adenocarcinoma (NMC) (P?=?0.082 and P?=?0.368). In multivariable analysis, no impact on survival was observed for OS (HR?=?1.22, 95 %CI: 0.89–1.68, P?=?0.208) and CSS (HR?=?1.21, 95 %CI: 0.84–1.74, P?=?0.296). After propensity score matching, nearly identical survival rates were observed (OS: HR?=?1.03, 95 %CI: 0.71–1.49, P?=?0.881 and CSS: HR?=?1.05, 95 %CI: 0.70–1.59, P?=?0.803).

Conclusions

The present population-based, propensity score matched analysis shows that mucinous histology does not affect survival in stage I–III appendiceal adenocarcinoma patients. Therefore, the same treatment strategies can be applied for patients with NMC and MC of the appendix.
  相似文献   
233.
A manual Danish register of patients with familial polyposis coli and their family members was established in 1971. The methods of collection of propositi, preparation of pedigrees, collection of call-up cases, and the organization of the register are described. A country-wide prophylactic proctosigmoidoscopic examination of first-degree relatives, aged 10 to 59 years, resulted in the detection of 42 call-up cases and by December 1982, 319 cases of polyposis were registered in 94 families. An evaluation of the number of collected propositi and call-up cases shows almost complete registration. Dr. Bülow has received grants from the Danish Cancer Society (809/71 and 87/80), “Max and Anna Friedmanns Legat,” and “Ferdinand og Ellen Hindsgauls Fond.”  相似文献   
234.
The aim of this study was to investigate knee intra-articular cartilage volume changes after a prolonged running bout in three footwear conditions. Twelve participants performed 75-minute running bouts in the three footwear conditions. Before and after each running bout, magnetic resonance imaging (MRI) scans were obtained using a high-resolution 3.0 Tesla MRI. Three-dimensional reconstruction of the cartilage plates of the patella, the femur, and the tibia was created to quantify cartilage volume change due to the 75-minute running bout. Three-dimensional biomechanical data were also collected using an integrated motion capture and force treadmill system. There were no statistically significant differences among shoe conditions for all anatomical regions. However, significant cartilage volume reductions at all anatomical sites were observed after the 75-minute running bout in each footwear condition. These data suggest that the intra-articular knee cartilage undergoes a significant reduction in cartilage volume during a prolonged run that may indicate an increase in joint loading. There was a considerable variation in cartilage volume between participants across footwear conditions indicating an individual cartilage volume response to footwear. An individualistic approach to footwear recommendations may help in minimizing this change in cartilage.  相似文献   
235.
236.
Transgenic Tg2576 mice expressing human amyloid precursor protein (hAPP) with the Swedish mutation are among the most frequently used animal models to study the amyloid pathology related to Alzheimer's disease (AD). The transgene expression in this model is considered to be neuron-specific. Using a novel hAPP-specific antibody in combination with cell type-specific markers for double immunofluorescent labelings and laser scanning microscopy, we here report that—in addition to neurons throughout the brain—astrocytes in the corpus callosum and to a lesser extent in neocortex express hAPP. This astrocytic hAPP expression is already detectable in young Tg2576 mice before the onset of amyloid pathology and still present in aged Tg2576 mice with robust amyloid pathology in neocortex, hippocampus, and corpus callosum. Surprisingly, hAPP immunoreactivity in cortex is restricted to resting astrocytes distant from amyloid plaques but absent from reactive astrocytes in close proximity to amyloid plaques. In contrast, neither microglial cells nor oligodendrocytes of young or aged Tg2576 mice display hAPP labeling. The astrocytic expression of hAPP is substantiated by the analyses of hAPP mRNA and protein expression in primary cultures derived from Tg2576 offspring. We conclude that astrocytes, in particular in corpus callosum, may contribute to amyloid pathology in Tg2576 mice and thus mimic this aspect of AD pathology.  相似文献   
237.
Inflated responsibility is increasingly regarded a pathogenetic mechanism in obsessive-compulsive disorder (OCD). In seeming contrast, there is mounting evidence that latent aggression is also elevated in OCD. Building upon psychodynamic theories that an altruistic fa?ade including exaggerated concerns for others is partly a defense against latent aggression, evidence was recently obtained for high interpersonal ambivalence in OCD patients relative to psychiatric and healthy controls using a newly developed instrument entitled the Responsibility and Interpersonal Behaviors and Attitudes Questionnaire (RIBAQ). A total of 46 OCD patients and 23 healthy participants took part in the present study. OCD patients displayed a higher social responsibility than controls. At the same time, patients also disclosed more latent aggression/calculating behavior and interpersonal distrust. While the pathogenic role of latent aggression is still not fully uncovered, it may deserve more consideration in treatment in view of frequent tensions in the families of OCD patients. Longitudinal studies with at-risk sample are needed to assess the relationship between problems with anger expression as well as (exaggerated) moral standards in OCD.  相似文献   
238.
Mickenautsch S 《Dental update》2011,38(9):634-8, 641-2, 644
Systematic reviews have been recommended as providing the best source of evidence to guide clinical decisions in dentistry. They appraise evidence from trials focused on investigating clinical effects of dental material categories, such as conventional glass-ionomer cements (GIC) or resin-modified GIC. In contrast, the general dental practitioner is introduced to these categories of materials in the form of branded or private product labels that are marketed during dental conventions or through advertisements. Difficulties may arise in recognizing material categories that have been subjected to systematic reviews, because of the multitude of product labels on the current market. Thus, the value and relevance of published systematic review evidence concerning the material categories represented by these labels may remain obscure. Based on a systematic literature search, this article identifies glass-ionomer cement product labels used during clinical trials which, in turn, were subsequently reviewed in systematic review articles (published between 15 April 2009 and 14 April 2011). This article further clarifies how these product labels relate to the systematic review conclusions. The results show that the conventional and resin-modified glass-ionomer cements that were used in most trials were marketed by GC and 3M ESPE, respectively. The conventional GICs used in most of the reviewed trials were Fuji III and Fuji IX, while Vitremer was the most commonly used resin-modified GIC. Evidence from the reviewed trials suggests that GIC provides beneficial effects for preventive and restorative dentistry. However, more trials of higher internal validity are needed in order to confirm (or disprove) these findings. Only GIC products of branded labels and none of private labels were identified, suggesting that private label GIC products have little or no research back-up. CLINICAL RELEVANCE: Dental products, such as glass-ionomers cements (GIC), can only be judged as effective when they are based on sufficient research back-up. Systematic reviews of clinical trials provide such back-up at the highest level. Thus clinicians must be able to identify GIC products for which reliable evidence from systematic reviews of clinical studies is available and know about what such evidence contains.  相似文献   
239.
Any transmission of vocal signals faces the challenge of acoustic interferences such as heavy rain, wind, animal or urban sounds. Consequently, several mechanisms and strategies have evolved to optimize signal‐to‐noise ratio. Examples to increase detectability are the Lombard effect, an involuntary rise in call amplitude in response to masking ambient noise, which is often associated with other vocal changes such as call frequency and duration, as well as the animals’ capability of limiting calling to periods where noise perturbation is absent. Previous studies revealed vocal flexibility and various audio‐vocal integration mechanisms in marmoset monkeys. Using acoustic perturbation triggered by vocal behaviour, we investigated whether marmosets are capable of exhibiting changes in call structure when perturbing noise starts after call onset or whether such effects only occur if noise perturbation starts prior to call onset. We show that marmosets are capable of rapidly modulating call amplitude and frequency in response to such noise perturbation. Vocalizations swiftly increased call frequency after noise onset indicating a rapid effect of perturbing noise on vocal motor production. Call amplitudes were also affected. Interestingly, however, the marmosets did not exhibit the Lombard effect as previously reported but decreased call intensity in response to noise. Our findings indicate that marmosets possess a general avoidance strategy to call in the presence of ambient noise and suggest that these animals are capable of counteracting a previously thought involuntary audio‐vocal mechanism, the Lombard effect. These findings will pave the way to investigate the underlying audio‐vocal integration mechanisms explaining these behaviours.  相似文献   
240.
Some animals have evolved task differentiation among their eyes. A particular example is spiders, where most species have eight eyes, of which two (the principal eyes) are used for object discrimination, whereas the other three pairs (secondary eyes) detect movement. In the ctenid spider Cupiennius salei, these two eye types correspond to two visual pathways in the brain. Each eye is associated with its own first- and second-order visual neuropil. The second-order neuropils of the principal eyes are connected to the arcuate body, whereas the second-order neuropils of the secondary eyes are linked to the mushroom body. We explored the principal- and secondary eye visual pathways of the jumping spider Marpissa muscosa, in which size and visual fields of the two eye types are considerably different. We found that the connectivity of the principal eye pathway is the same as in C. salei, while there are differences in the secondary eye pathways. In M. muscosa, all secondary eyes are connected to their own first-order visual neuropils. The first-order visual neuropils of the anterior lateral and posterior lateral eyes are connected with a second-order visual neuropil each and an additional shared one (L2). In the posterior median eyes, the axons of their first-order visual neuropils project directly to the arcuate body, suggesting that the posterior median eyes do not detect movement. The L2 might function as an upstream integration center enabling faster movement decisions.  相似文献   
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