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1.
Numerous studies showed that postural balance improves through light touch on a stable surface highlighting the importance of haptic information, seemingly downplaying the mechanical contributions of the support. The present study examined the mechanical effects of canes for assisting balance in healthy individuals challenged by standing on a beam. Sixteen participants supported themselves with two canes, one in each hand, and applied minimal, preferred, or maximum force onto the canes. They positioned the canes in the frontal plane or in a tripod configuration. Statistical analysis used a linear mixed model to evaluate the effects on the center of pressure and the center of mass. The canes significantly reduced the variability of the center of pressure and the center of mass to the same level as when standing on the ground. Increasing the exerted force beyond the preferred level yielded no further benefits, although in the preferred force condition, participants exploited the altered mechanics by resting their arms on the canes. The tripod configuration allowed for larger variability of the center of pressure in the task-irrelevant anterior–posterior dimension. High forces had a destabilizing effect on the canes: the displacement of the hand on the cane handle increased with the force. Given this static instability, these results show that using canes can provide not only mechanical benefits but also challenges. From a control perspective, effort can be reduced by resting the arms on the canes and by channeling noise in the task-irrelevant dimensions. However, larger forces exerted onto the canes can also have destabilizing effects and the instability of the canes needs to be counteracted, possibly by arm and shoulder stiffness. Insights into the variety of mechanical effects is important for the design of canes and the instructions of how to use them.  相似文献   
2.
Cochrane reviews are systematic reviews with meta analysis published by the Cochrane collaboration, in the Cochrane Database of Systematic Reviews (CDSR). These reviews provide the clinicians with the highest level of evidence as they use a highly structured and transparent systematic review model to address a specific research question.The management of partially absent dentition is routinely under taken by general dentist and Prosthodontist but clinical practice guidelines based on evidence to this common problem is yet to be summarized. This Cochrane systematic review aims to address the effect of different prosthesis for the treatment of partially absent dentition in the terms of, Long-term success, function, morbidity, and patient satisfaction. All randomized controlled trials were searched till March 18, 2011, based on the inclusion and exclusion criteria, 21 trials were included and 32 trials were excluded and, it was critically appraised using the Cochrane methodology for interventions. The summary of evidence from the study concludes that there is insufficient evidence to state the effectiveness of removable and fixed prosthesis in partially edentulous subjects in the following four outcomes. There were insufficient trials to perform a meta-analysis and sensitivity analysis.This evidence-based summary emphasizes and reinforces the need to reassess the quality of research currently pursued in our profession, to address the need to provide higher level of evidence for common conditions like partial edentulousness. The included studies are basically not from our population too, hence the urgency to address this critical issue.  相似文献   
3.

Background

With modern advancements in preoperative imaging for liver surgery, intraoperative ultrasonography (IOUS) may be perceived as superfluous. Our aim was to determine if IOUS provides new information that changes surgical strategy in hepatic resection.

Methods

We retrospectively analyzed 121 consecutive liver resections performed at a single institution. Preoperative computed tomography and/or magnetic resonance imaging determined the initial surgical strategy. The size, location and number of lesions were compared between IOUS and preoperative imaging. Reviewing the operative report helped determine if new IOUS findings led to changes in surgical strategy. Pathology reports were analyzed for margins.

Results

Of 121 procedures analyzed, IOUS was used in 88. It changed the surgical plan in 15 (17%) cases. Additional tumours were detected in 10 (11%) patients. A change in tumour size and location were detected in 2 (2%) and 3 (4%) patients, respectively. Surgical plans were altered in 7 (8%) cases for reasons not related to IOUS. There was no significant difference (p = 0.74) in average margin length between the IOUS and non-IOUS groups (1.09 ± 1.18 cm v. 1.18 ± 1.05 cm).

Conclusion

Surgical strategy was altered owing to IOUS results in a substantial number of cases, and IOUS-guided resection planes resulted in R0 resections in nearly all procedures. The best operative plan in hepatic resection includes IOUS.  相似文献   
4.
Diabetic foot ulcers are responsible for more hospitalizations than any other complication of diabetes. Bacterial infection is recognized as an important factor associated with impaired healing in diabetic ulcers. Pseudomonas aeruginosa is the most frequently detected Gram‐negative pathogen in diabetic ulcers. P. aeruginosa infection has been shown to impair healing in diabetic wounds in a manner that correlates with its ability to form biofilm. While the majority of infections in diabetic ulcers are biofilm associated, 33% of infections are nonbiofilm in nature. P. aeruginosa is the most prevalent Gram‐negative pathogen in all diabetic wound types, which suggests that the deleterious impact of P. aeruginosa on healing in diabetic wounds goes beyond its ability to form biofilm and likely involves other factors. The Type III Secretion System (T3SS) virulence structure is required for the pathogenesis of all P. aeruginosa clinical isolates, suggesting that it may also play a role in the inhibition of wound repair in diabetic skin ulcers. We evaluated the role of T3SS in mediating P. aeruginosa–induced tissue damage in the wounds of diabetic mice. Our data demonstrate that P. aeruginosa establishes a robust and persistent infection in diabetic wounds independent of its ability to form biofilm and causes severe wound damage in a manner that primarily depends on its T3SS.  相似文献   
5.
KIR (Killer Immunoglobulin‐like Receptor) variants influence immune responses and are genetic factors in disease susceptibility. Using sequence‐specific priming PCR, we have previously described the diversity of KIR genes in term of presence/absence in northeastern Thais (NETs). To provide additional resolution beyond conventional methods, quantitative PCR was applied to determine KIR copy number profiles. Novel expanded and contracted KIR copy number profiles were identified at cumulatively high frequencies. These all comprise haplotypes with duplication (6·9%) or deletion (2·7%) of KIR3DL1/S1 along with adjacent genes. Five expanded KIR profiles comprised haplotypes with duplications of KIR2DP1, 2DL1, 3DP1, 2DL4, 3DL1/S1 and 2DS1/4, whereas two contracted profiles contained only a single copy of KIR3DP1, 3DL1/S1 and 2DL4. Using a KIR haplotype prediction program (KIR Haplotype Identifier), 14% of NET haplotypes carried atypical haplotypes based on the gene copy number data.  相似文献   
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Obesity, metabolic syndrome, and type 2 diabetes (T2D) are related disorders with widespread deleterious effects throughout the body. One important target of damage is the brain. Persons with metabolic disorders are at significantly increased risk for cognitive decline and the development of vascular dementia and Alzheimer’s disease. Our review of available evidence from epidemiologic, clinical, and basic research suggests that neural dysfunction from T2D-related disease results from several underlying mechanisms, including metabolic, inflammatory, vascular, and oxidative changes. The relationships between T2D and neural dysfunction are regulated by several modifiers. We emphasize 2 such modifiers, the genetic risk factor apolipoprotein E and an age-related endocrine change, low testosterone. Both factors are independent risk factors for Alzheimer’s disease that may also cooperatively regulate pathologic interactions between T2D and dementia. Continued elucidation of the links between metabolic disorders and neural dysfunction promises to foster the development of effective therapeutic strategies.  相似文献   
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