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1.
摘要 目的:观察经脐单孔腹腔镜疝囊高位结扎术治疗腹股沟斜疝患儿的疗效及对血清炎性指标和免疫功能的影响。方法:研究为回顾性研究,选取2018年1月~2020年12月期间在我院接受治疗的198例腹股沟斜疝患儿的临床资料,按照手术方式的差异分为传统组(97例)和微创组(101例)。传统组接受开放性腹股沟斜疝疝囊高位结扎术,微创组接受经脐单孔腹腔镜疝囊高位结扎术,观察两组手术相关指标、血清炎性指标和免疫功能变化情况,记录随访期间并发症发生率并作组间对比。结果:与传统组相比,微创组切口总长度更短,手术时间、住院时间缩短,术中出血量减少(P<0.05)。术后2 d组间对比,微创组免疫球蛋白M(IgM)、免疫球蛋白A(Ig A)、免疫球蛋白G(IgG)水平均高于传统组(P<0.05)。术后2 d组间对比,微创组血清白介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)、C反应蛋白(CRP)、白细胞计数均低于传统组(P<0.05)。与传统组相比,微创组随访期间并发症发生率更低(P<0.05)。结论:经脐单孔腹腔镜疝囊高位结扎术治疗腹股沟斜疝患儿,具有创伤小、手术时间短、并发症少、术后恢复快等优势,且该术式引起的炎症反应及免疫抑制程度均较传统治疗更轻,是治疗此类患儿的良好选择。  相似文献   
2.
The fecundity patterns of S and L type rotifers of Brachionus plicatilis   总被引:1,自引:0,他引:1  
Fecundity patterns of S and L type rotifers Brachionus plicatilis, which were previously found to have distinct growth ability, were analyzed using data of age-specific fecundity. The data were obtained by individual cultures of S and L type strains at 17, 24 and 34 °C. The pattern was analyzed by using normal probability functions. When the age was transformed into logarithmic value, the S and L types had an identical pattern of fecundity at every temperature. This fact indicates that the difference of the growth response to the temperature between S and L type strains stemmed only from the differences in net reproduction rate, not from the pattern.  相似文献   
3.
Vascular support structures are important devices for treating valve stenosis. A large population of patients is treated for valvular disease and the preferred mode of treatment is percutaneous valve replacement. Stent devices are proving to be an improved technology in minimally invasive cardiac surgery. This new technology provides highly effective results at minimal cost and with a short duration of hospitalisation. Stents as a supporting structure for tissue valves have evolved over the years into remarkably useful and effective devices. During this process, a number of specific designs have come and gone, and a few have remained. Many design changes were successful, and many were not. This article describes the merits and demerits of various stent designs and details the specific reasons why a particular novel design is expected to be the most suitable implant during and after percutaneous aortic valve replacement.  相似文献   
4.
Previous studies have compared grassland restoration techniques based on resulting species richness and composition. However, none have determined if different techniques generate different plant distributions in space, which may further impact restoration success. This study tests if there are quadrat‐scale (1 m2) differences between paired drilled and broadcast plantings in diversity, composition, and plant distributions. Higher competition intensity in and more contiguous spaces between rows in drill‐seeded restorations were hypothesized to result in larger patches of native grasses and exotic species. Two paired drill‐ and broadcast‐seeded plantings were sampled in June 2007 in Iowa, U.S.A. Within 10 quadrats in each planting, we measured species abundance with point intercept sampling and plant distributions by dividing the quadrat into 64 cells and recording the most abundant species in each cell. Drilled and broadcast plantings at both sites had similar Simpson’s diversity and evenness. However, the effect of planting type on species richness, composition, and plant distribution was site dependent. Native warm‐season grasses in one site, and exotic species in the second, occupied more space and were distributed in larger patches in drilled plantings. Furthermore, drilled canopies consistently captured more light than broadcast canopies. This suggests that initial differences in seed placement can affect resulting plant distributions, resource use, and potentially long‐term species turnover. Mechanisms structuring vegetation in these communities need to be further investigated to determine if this approach can provide more information on long‐term diversity maintenance in restorations than traditional measures.  相似文献   
5.
大亚湾红树林研究1.澳头港的红树植物群落   总被引:1,自引:0,他引:1  
本文报道了大亚湾澳头港附近的红树植物群落的种类组成、结构、外貌及演替。该地区红树群落的主要类型有7个,即白骨壤群落、白骨壤桐花树群落、白骨壤+秋茄桐花树群落、海漆木榄群落、海漆桐花树群落、桐花树群落、老鼠勒群落。  相似文献   
6.
Product takeback calls for sound strategies of product recovery management One such strategy-is the reuse of the components of a product. There are consumer products such as power tools whose most expensive component, the electric motor; offers potential for reuse. Empirical evidence reveals that the lifetime of a motor often exceeds the life-time of the product using it. This article focuses on the reuse of electric motors. For this purpose, a novel circuit was developed that measures, computes, and records parameters strongly correlated with the degradation of a motor during the use stage of the product. This circuit, called electronic data log (EDL), provides valuable insights into the usage patterns of products. The data recorded during the use stage are retrieved after product takeback as a basis for reuse decisions. In this article, the trade-off between higher initial manufacturing cost caused by the EDL and cost savings from the reuse of used motors is analyzed. The problem of misclassifications of used motors is also addressed. It is shown that the return rate of used products is the critical parameter determining the economic efficiency of a motorreuse strategy based on EDLs. The analysis shows that the implementation of EDLs in products as an enabler for motor reuse may be associated with large cost savings  相似文献   
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Anisotropy is one of the most meaningful determinants of biomechanical behaviour. This study employs micro-computed tomography (μCT) and image techniques for analysing the anisotropy of regenerative medicine polymer scaffolds. For this purpose, three three-dimensional anisotropy evaluation image methods were used: ellipsoid of inertia (EI), mean intercept length (MIL) and tensor scale (t-scale). These were applied to three patterns (a sphere, a cube and a right prism) and to two polymer scaffold topologies (cylindrical orthogonal pore mesh and spherical pores). For the patterns, the three methods provided good results. Regarding the scaffolds, EI mistook both topologies (0.0158, [ ? 0.5683; 0.6001]; mean difference and 95% confidence interval), and MIL showed no significant differences (0.3509, [0.0656; 0.6362]). T-scale is the preferable method because it gave the best capability (0.3441, [0.1779; 0.5102]) to differentiate both topologies. This methodology results in the development of non-destructive tools to engineer biomimetic scaffolds, incorporating anisotropy as a fundamental property to be mimicked from the original tissue and permitting its assessment by means of μCT image analysis.  相似文献   
10.
We investigated the combined use of cast net (CN), otter trawl (OT), and encircling gill net (EG) to characterize the richness, composition, and abundance of species and functional groups of the subtidal fish assemblage in a subtropical shallow ecosystem in Brazil. Our hypothesis, that this combination would improve faunal characterization, was supported. The CN best sampled small pelagic planktivores (e.g., juvenile sardines) and detritivores (e.g., juvenile mullets); OT, small and large demersal benthivores (e.g., mojarras and croakers); and EG, large fast‐swimming species, such as piscivores (e.g., snooks and weakfishes) and large detritivores (adult mullets). The mean and total richness were best sampled with the OT. The most accurate richness estimate using non‐parametric estimators was reached by combining all three types of gear. Our findings emphasize that the careful sampling gear selection and the use of multiple gears are indispensable for solid characterizations of coastal fish fauna, and consequently, for the success of monitoring and research programs.  相似文献   
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