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851.
The microbiological quality of indoor air is creating an increasing interest especially as far as places at risk such as hospitals, clinics, medical and odontological surgeries are concerned. Working with the odontologists of our province we have been carrying out a research aimed at preventing cross-infection in odontology. Data obtained from the microbiological analysis of the air in 36 surgeries using S.A.S were discussed during the V National Congress of Aerobiology. During that congress the need of setting a standardized technique of air sampling in indoor environments emerged and two routes have been identified: (1) the gravimetric technique on open plate exposed for an hour close to the dental unit and (2) the use of the volumetric sampler which gives qualitative data expressed as colonies forming units per cubic metre of air. However, both of these techniques present some problems: using the first a loss of micro-organisms has been noticed due to the variability of the air fluxes and the different weight of the biological particles; using the second one the bacterial charge is also undervalued, because of the stress suffered by the bacteria with the use of the volumetric sampler. In the light of these statements we decided to use both in dental surgeries to be able to compare the results obtained. Our project is expected to carry out at least one inspection and the relative sampling (indoor air, water of the dental unit, air of the syringe, disinfectant solution, surface tampons, biological test of sterility) in each dental surgery in the territory of our health Unit, located in Ferrara, Northern Italy.  相似文献   
852.
The structure of the sexually modified 1st 2 pairs of swimmerets of the male squat lobster Galathea strigosa are described, and a reflex involving these swimmerets is characterised. The endopodite of the 1st swimmeret forms a partially rolled lamina which hooks around the “bottle brush” end of the endopodite of the 2nd swimmeret. Mechanical stimulation of a sensitive region on the endopodite of each 1st swimmeret causes retraction of both 2nd swimmerets, inducing the “bottle brush” to push up within the endopodite of the 1st swimmeret. The reflex is thought to be involved in sperm transfer during copulation. Neural information travels between the 1st and 2nd swimmerets in the interganglionic connective ipsilateral to the stimulus.  相似文献   
853.
854.
We investigated the utility of the fluorescent dye Deep Red Anthraquinone 5 (DRAQ5) for digital staining of optically sectioned skin in comparison to acridine orange (AO). Eight fresh-frozen thawed Mohs discard tissue specimens were stained with AO and DRAQ5, and imaged using an ex vivo confocal microscope at three wavelengths (488 nm and 638 nm for fluorescence, 785 nm for reflectance). Images were overlaid (AO + Reflectance, DRAQ5 + Reflectance), digitally stained, and evaluated by three investigators for perceived image quality (PIQ) and histopathological feature identification. In addition to nuclear staining, AO seemed to stain dermal fibers in a subset of cases in digitally stained images, while DRAQ5 staining was more specific to nuclei. Blinded evaluation showed substantial agreement, favoring DRAQ5 for PIQ (82%, Cl 75%-90%, Gwet's AC 0.74) and for visualization of histopathological features in (81%, Cl 73%-89%, Gwet's AC 0.67), supporting its use in digital staining of multimodal confocal micrographs of skin.  相似文献   
855.
Background: Preoperative images such as computed tomography scans or magnetic resonance imaging contain lots of valuable information that are not easily available for surgeons during an operation. To help the clinicians better target the structures of interest during an intervention, many registration methods that align preoperative images onto the intraoperative view of the organs have been developed. For important organ deformation, biomechanically-based registration has proven to be a method of choice.Method: Using an existing biomechanically-based registration algorithm for laparoscopic liver surgery we investigate in this paper the influence of the heterogeneity of the liver on the registration result.Results: No statistical difference in the results was found between the registration performed with the homogeneous model and the one carried out with the heterogeneous model.Conclusion: As the use of an heterogeneous model does not improve significantly the registration result and increase the computation time we recommend to perform the type of registration task described in the paper with a simplified homogeneous model.  相似文献   
856.
Abstract

Objective

Despite wide interest in glycocalyx biomarkers, their values in healthy individuals, patients after abdominal surgery, and septic patients have been poorly understood.  相似文献   
857.
Traumatic situations in animals induce responses including pain, expressed through behavioural and physiological pathways such as inflammation, oxidative stress, hypothalamic–pituitary–adrenal (HPA) axis and autonomic nervous system. As some of these systems can also be activated during excitement and situations with a positive valence, their use as a means to assess pain response is difficult. We explored (i) how these five aforementioned pathways change in sheep exposed to various degrees of invasiveness of surgical procedures despite a therapeutic regimen and (ii) whether a multiparametric analysis that combines information from these five pathways enhances the discrimination between these situations, and estimates the relative importance of these pathways in the response. We used 24 adult sheep split into four treatments: Control (C; no fasting, no anaesthesia, no surgery), Sham (S; fasting, anaesthesia, no surgery), Rumen Canulation (R; fasting, anaesthesia, rumen cannulation) and Rumen–Duodenal–Ileum cannulation (RDI; fasting, anaesthesia, cannulation of the rumen, duodenum and ileum). Sheep’ responses were measured for 5 days after surgery. When considering each behavioural or physiological pathway independently, discrimination between treatments was acceptable, its sensitivity (Se) ranging from 0% to 100%, and its specificity (Sp) ranging from 62% to 100%. The multiparametric analysis gathering information from the five pathways enhanced the effectiveness of discrimination between treatments (Se, 50% to 100%; Sp, 82% to 100%), and gave additional information on the relative contribution of each pathway to the global sheep response. Sheep global response was higher when exposed to a surgery, and increased with the surgery invasiveness. This response relied mostly on inflammation (absolute correlation for haptoglobin, 0.89), HPA (cortisol, 0.85) and behaviour (antalgic postures, 0.85). The multiparametric approach seems to be a promising tool to discriminate between different degrees of invasiveness of surgical procedures.  相似文献   
858.
Misalignment and soft-tissue imbalance in total knee arthroplasty (TKA) can cause discomfort, pain, inadequate motion and instability that may require revision surgery. Balancing can be defined as equal collateral ligament tensions or equal medial and lateral compartmental forces during the flexion range. Our goal was to study the effects on balancing of linear femoral component misplacements (proximal, distal, anterior, posterior); and different component rotations in mechanical alignment compared to kinematic alignment throughout the flexion path. A test rig was constructed such that the position of a standard femoral component could be adjusted to simulate the linear and rotational positions. With the knee in neutral reference values of the collateral tensions were adjusted to give anatomic contact force patterns, measured with an instrumented tibial trial. The deviations in the forces for each femoral component position were then determined. Compartmental forces were significantly influenced by 2 mm linear errors in the femoral component placement. However, the errors were least for a distal error, equivalent to undercutting the distal femur. The largest errors mainly increase the lateral condyle force, occurred for proximal and posterior component errors. There were only small contact force differences between kinematic and mechanical alignment. Based on these results, surgeons should avoid overcutting the distal femur and undercutting the posterior femur. However, the 2–3 degrees varus slope of the joint line as in kinematic alignment did not have much effect on balancing, so mechanical or kinematic alignment were equivalent.  相似文献   
859.
目的:探讨微创后入路手术治疗肩胛骨骨折的临床疗效。方法:选取2009年6月~2014年1月在我院接受后路内固定手术治疗的40例肩胛骨骨折,治疗组20例,行微创后入路内固定术,对照组20例,行Judet入路内固定术。比较两组间手术时间、术中出血量、切口总长度及术后肩关节功能Constant评分。结果:40例患者均获随访,随访时间12~36个月,平均16.5个月。治疗组手术时间、术中出血量、切口总长度均优于对照组(均P0.05),术后6个月肩关节功能:治疗组优15例,良3例,可1例,差1例,优良率90%,对照组优14例,良2例,可3例,差1例,优良率80%。两组优良率比较,差异有统计学意义(P0.05)。两组均无感染、骨折延迟愈合或不愈合。对照组1例发生肩胛上神经卡压。结论:微创后入路手术操作简单,创伤小,恢复快,是一种安全有效的肩胛骨骨折手术入路。  相似文献   
860.
Monitoring the bioenergetics of leucocytes is now emerging as an important approach in translational research to detect mitochondrial dysfunction in blood or other patient samples. Using the mitochondrial stress test, which involves the sequential addition of mitochondrial inhibitors to adherent leucocytes, we have calculated a single value, the Bioenergetic Health Index (BHI), which represents the mitochondrial function in cells isolated from patients. In the present report, we assess the BHI of monocytes isolated from the post-operative blood and post-operative pericardial fluid (PO-PCF) from patients undergoing cardiac surgery. Analysis of the bioenergetics of monocytes isolated from patients’ PO-PCF revealed a profound decrease in mitochondrial function compared with monocytes isolated from their blood or from healthy controls. Further, patient blood monocytes showed no significant difference in the individual energetic parameters from the mitochondrial stress test but, when integrated into the BHI evaluation, there was a significant decrease in BHI compared with healthy control monocytes. These data support the utility of BHI measurements in integrating the individual parameters from the mitochondrial stress test into a single value. Supporting our previous finding that the PO-PCF is pro-oxidant, we found that exposure of rat cardiomyocytes to PO-PCF caused a significant loss of mitochondrial membrane potential and increased reactive oxygen species (ROS). These findings support the hypothesis that integrated measures of bioenergetic health could have prognostic and diagnostic value in translational bioenergetics.  相似文献   
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