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1.
:痔(Haemorrhoids)是直肠末端黏膜、肛管皮肤下痔静脉丛屈曲或扩张而形成的柔软静脉团,是外科常见的疾病。尽管保守治
疗适用于大部分患者人群,但是手术治疗却适用于大部分严重病人,比如外剥内扎术就被视为治疗IV 度痔的金标准。痔的手术
治疗有传统手术和微创手术,为了减轻患者的痛苦、加速恢复、减少并发症的发生,PPH 和TST 等新型手术方式也逐渐被应用于
III痔的治疗中,这些手术方法的目的是纠正痔疮的病因及病理生理基础,具有微创、痛苦小的特点,但往往复发率较高。随着手术
方式的改进以及操作技术的成熟,痔的外科治疗效果也取得了长足的进步。本文对混合痔的外科手术技术作一综述,为临床治疗
提供理论依据。 相似文献
2.
目的:评价重庆市各级内镜医疗机构医疗执业现状,分析导致医疗执业状况不佳的原因,为改善医疗执业状况和医患关系,促进我国医疗执业健康、和谐发展提供参考。方法:对重庆市137家已开展消化内镜诊疗的医院,506名内镜医师进行调查,调查内容主要包括重庆内镜医师当前的基本素质状况以及医师们如何看待所面临的卫生改革、所处执业状况、管理体制、行业内协会职能、执业内镜医师法、继续教育培训等。结果:54.81%消化内镜医师对自己的工作表示满意,40.13%的医师感觉工作一般;在对医疗事故的调查中,遇到和未遇过医疗事故的比例分别为5%和95%;目前主要困惑重庆消化内镜医师的是以下问题:缺乏休息时间、工作较大强度,比例占到36.09%。结论:应改善消化内镜医师执业环境,缓解消化内镜医师工作压力,有效地发挥媒体导向作用,加强法制建设。 相似文献
3.
A better understanding of how ecological novelty influences interactions in new combinations of species is key for predicting interaction outcomes, and can help focus conservation and management efforts on preventing the introduction of novel organisms or species (including invasive species, GMOs, synthetic organisms, resurrected species and emerging pathogens) that seem particularly ‘risky’ for resident species. Here, we consider the implications of different degrees of eco‐evolutionary experience of interacting resident and non‐resident species, define four qualitative risk categories for estimating the probability of successful establishment and impact of novel species and discuss how the effects of novelty change over time. Focusing then on novel predator–prey interactions, we argue that novelty entails density‐dependent advantages for non‐resident species, with their largest effects often being at low prey densities. This is illustrated by a comparison of predator functional responses and prey predation risk curves between novel species and ecologically similar resident species, and raises important issues for the conservation of endangered resident prey species. 相似文献
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Conserving biological diversity requires a major effort in conducting survey and inventories, establishing priorities, selecting protected areas, managing resources and monitoring the effects of management. Systematics has an important contribution to make to each of these five major activities. Further, the new Convention on Biological Diversity requires systematics information to support action under virtually all of its substantive conservation and sustainable use articles. It seems apparent that large reference collections contribute directly to development, and development assistance agencies should recognize that investing in maintaining these collections is a legitimate form of development assistance. 相似文献
8.
Scott Raymond John Koehn Zeb Tonkin Charles Todd Daniel Stoessel Graeme Hackett Justin O'Mahony Kelvin Berry Jarod Lyon Joanne Sharley Paul Moloney 《Restoration Ecology》2019,27(6):1463-1472
Globally, river degradation has decimated freshwater fish populations. To help reverse this trend in a southeastern Australia river, we used multiple restoration actions, including reintroduction of instream woody habitat, riparian revegetation, removal of a weir hindering fish movement, fencing out livestock, and controlling riparian weeds. We monitored the responses of native fish at the segment scale (20 km) and reach scale (0.3 km) over 7 years to assess the effectiveness of the different restoration strategies. Two closely related species, Murray cod Maccullochella peeli and trout cod Maccullochella macquariensis, increased at the restored segment compared with the control segment. However, inherent differences between river segments and low sample size hampered assessment of the mechanisms responsible for segment‐scale changes in fish abundance. In contrast, at the reach scale, only M. peeli abundance significantly increased in reaches supplemented with wood. These differential responses by 2 closely related fish species likely reflect species‐specific responses to increased habitat availability and enhanced longitudinal connectivity when the weir improved passage around a fishway. Changes in M. peeli abundance in segments supplemented with and without wood suggest an increase in carrying capacity and not simply a redistribution of individuals within the segment, facilitated the observed expansion. Our findings confirm the need to consider individual fish species' habitat preferences carefully when designing restoration interventions. Further, species‐specific responses to restoration actions provide waterway managers with precise strategies to target fish species for recovery and the potential to predict fish outcomes based on ecological preferences. 相似文献
9.
Laurens E. Howle Scott D. Kraus Timothy B. Werner Douglas P. Nowacek 《Marine Mammal Science》2019,35(3):760-778
Population estimates of the critically endangered North Atlantic right whale (Eubalaena glacialis) put the number of individuals at 458 with the actual number likely being lower due to a recent unusual mortality event. Entanglement with fixed fishing gear is the most significant cause of mortality of North Atlantic right whales. There remains little documentation of how North Atlantic right whales become enwrapped during an encounter with fixed fishing gear. In order to gain a better understanding of how entanglements might occur, an interactive simulator was developed that allows the user to swim a virtual whale model using a standard game controller through a gear field in an attempt to re‐create an entanglement. The morphologically accurate right whale model produces realistic swimming motions and is capable of pectoral fin motions in response to user input. Using the simulator, gear entanglements involving the pectoral flippers including ropes wrapping around the body and entanglements involving the tailstock were re‐created. Entanglements involving the pectoral flippers with body wraps were more easily generated than entanglements involving the tailstock only. The simulator should aid scientists, fisheries experts, fishing gear designers, and bycatch reduction scientists in understanding entanglement dynamics and testing potential new gear configurations. 相似文献
10.
《植物生态学报》2018,42(8):806
翅果能够依靠风力进行传播, 可能是被子植物快速散布和物种分化的一个重要因素。狭义的翅果是指果皮延伸成翅且不开裂的干果; 广义的翅果则包括果皮、花被片或苞片形成果翅的所有果实。根据果翅形态及其生长方式的不同, 广义的翅果可分为单侧翅果、周位翅果(圆翅果与蝶翅果)、棱翅果、披针翅果、翼状萼翅果、叶状苞翅果6种类型, 其空中运动方式有自旋式(单侧翅果、翼状萼翅果)、波浪式(周位翅果、叶状苞翅果)、翻滚自旋式(周位翅果)、直升机式(披针翅果、翼状萼翅果)和滚筒式(棱翅果)。棱翅果与圆翅果在被子植物基部类群樟目就有发生, 并同时出现在单子叶植物和双子叶植物中, 可能是最早出现的翅果类型。翅果的演化过程呈现出果翅数量增加、果翅偏向单侧和果翅负荷(果实质量与果翅面积之比)降低的趋势, 以利于适应较小的风并增加传播距离。果翅除了促进果实与种子的风力传播外, 还具有物理防御、调节种子萌发和促进二次传播等作用。泛热带分布的金虎尾科有着极其丰富的翅果类型, 与其多次跨洋长距离扩散密切相关, 可以作为研究翅果适应与演化的一个模式类群。结合生态和演化-发育生物学方法, 研究不同类型翅果在适应风力传播方面的差异、萼片或苞片发育成翅的分子与遗传机制、翅果不同类型的演化历史及其对被子植物物种多样性的影响等是今后值得探讨的重要问题。 相似文献