重庆市消化内镜医师执业状况调查报告

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。     

Best hyperspectral indices for tracing leaf water status as determined from leaf dehydration experiments

Leaf water status information is highly needed for monitoring plant physiological processes and assessing drought stress. Retrieval of leaf water status based on hyperspectral indices has been shown to be easy and rapid. However, a universal index that is applicable to various plants remains a considerable challenge, primarily due to the limited range of field-measured datasets. In this study, a leaf dehydration experiment was designed to obtain a relatively comprehensive dataset with ranges that are difficult to obtain in field measurements. The relative water content (RWC) and equivalent water thickness (EWT) were chosen as the surrogates of leaf water status. Moreover, five common types of hyperspectral indices including: single reflectance (R), wavelength difference (D), simple ratio (SR), normalized ratio (ND) and double difference (DDn) were applied to determine the best indices. The results indicate that values of original reflectance, reflectance difference and reflectance sensitivity increased significantly, particularly within the 350–700 nm and 1300–2500 nm domains, with a decrease in leaf water. The identified best indices for RWC and EWT, when all the species were considered together, were the first derivative reflectance based ND type index of dND (1415, 1530) and SR type index of dSR (1530, 1895), with R² values of 0.95 (p < 0.001) and 0.97 (p < 0.001), respectively, better than previously published indices. Even so, different best indices for different species were identified, most probably due to the differences in leaf anatomy and physiological processes during leaf dehydration. Although more plant species and field-measured datasets are still needed in future studies, the recommend indices based on derivative spectra provide a means to monitor drought-induced plant mortality in temperate climate regions.     

单抗药物专题报告——走过孕育期，收获正当时（Ⅰ）

单抗药物以靶向性强、特异性高、副反应小等优势在癌症、自身免疫性疾病等治疗领域取得了快速发展,成为医药行业增速最快的 细分领域。报告采用文献调研、数据库检索、数据统计与分析等定性定量研究方法,从竞争优势、应用领域、给药剂型、产业现状、成长 路径等角度对国内外单抗药物领域进行多角度、多层次的分析,旨在为相关医药企业明确发展方向、确定产品研发思路及制定市场策略提 供参考。     

Nutritional and antinutritional attributes of faba bean (Vicia faba L.) germplasms growing in Bihar,India

Eleven germplasms of faba bean seeds from four agroclimatic regions of Bihar, India, have been investigated to estimate their nutritional (soluble protein, free amino acids, starch, reducing and non reducing sugar, total soluble sugar) and antinutritional (total extractable phenol and condensed tannin/proanthocyanidin) parameters. These parameters were found in varying concentration in all genotypes studied. The highest concentration of total extractable phenol and proanthocyanidin (condensed tannin) (2.56 and 1.59 % leucocyanidin equivalents respectively on dry matter basis) were found in Samastipur while the lowest from Patna (0.95 and 0.426 % leucocyanidin equivalent on dry matter basis). The different nutritional parameters were also found to be in variable concentration among different germplasms viz. total soluble protein ≈ 20–32 %, free amino acids ≈ 188–348 mg/100 g, starch ≈ 27–33 %, reducing sugars ≈ 85–188 mg/100 g, non reducing sugars ≈ 0.7–1.7 % and total soluble sugars ≈ 0.8–1.9 %.     

纳米氧化锌和接种丛枝菌根真菌对大豆生长及营养吸收的影响

纳米氧化锌是应用最广的人工纳米颗粒(nanoparticles,NPs)之一,具有一定生物毒性。丛枝菌根(arbuscular mycorrhizal,AM)真菌能与陆地上80%以上的高等植物形成丛枝菌根共生体,并能改善宿主植物矿质营养,提高其抗逆性。然而纳米ZnO与丛枝菌根的关系尚不清楚。通过温室沙培盆栽试验,研究了施加不同水平纳米ZnO(0、500、1000、2000、3000 mg/kg)和接种AM真菌Acaulospora mellea对大豆生长及营养状况的影响。结果表明,3000 mg/kg的纳米ZnO显著抑制大豆植株生长,表现出植物毒性,在其他水平时没有显著影响。纳米ZnO在施加水平500、1000 mg/kg时没有抑制AM真菌对大豆根系的侵染,但是高施加水平(2000 mg/kg)时对AM真菌产生毒害,几乎完全抑制大豆根系菌根侵染。接种AM真菌仅在500 mg/kg纳米ZnO时显著促进大豆生长,增加大豆植株对P、K、N的吸收,降低根系Zn含量。纳米ZnO可能会持续释放锌离子,并抑制大豆根系对矿质营养元素的吸收,从而产生生物毒性,而AM真菌与大豆根系的共生可起到有益作用。     

Sex Attraction and Mating in Bursaphelenchus okinawaensis and B. xylophilus

The fungal feeding, hermaphroditic Bursaphelenchus okinawaensis is a laboratory model to understand the biology of Bursaphelenchus. The extent to which B. okinawaensis can be used to model Bursaphelenchus xylophilus mating was investigated. A chemotaxis assay was conducted to examine whether B. xylophilus and B. okinawaensis produce and respond to volatile sex attractants. Unmated B. xylophilus females were found to attract B. xylophilus males. Similarly, old (sperm depleted) but not young (sperm repleted) B. okinawaensis hermaphrodites attract B. okinawaensis males. Thus, in both species, sperm status corresponds to its ability to attract males. B. xylophilus males also produce a volatile pheromone that attracts both mated and unmated females. A second assay, in which the behavior of males on petri plates in the presence of different females or hermaphrodites of Bursaphelenchus was observed, revealed that B. xylophilus unmated females attract B. okinawaensis males, and B. okinawaensis old hermaphrodites attract B. xylophilus males. These observations suggested that the pheromones of Bursaphelenchus work to some extent across species. Mating behavior through spicule insertion occurs across species, suggesting that postcopulatory mechanisms prevent production of interspecific progeny. The hermaphroditic B. okinawaensis will be a useful model to conduct genetic studies for the understanding of the molecular mechanisms underlying mating behavior in Bursaphelenchus nematodes.     

A comprehensive analysis of root morphological changes and nitrogen allocation in maize in response to low nitrogen stress

The plasticity of root architecture is crucial for plants to acclimate to unfavourable environments including low nitrogen (LN) stress. How maize roots coordinate the growth of axile roots and lateral roots (LRs), as well as longitudinal and radial cell behaviours in response to LN stress, remains unclear. Maize plants were cultivated hydroponically under control (4 mm nitrate) and LN (40 μm ) conditions. Temporal and spatial samples were taken to analyse changes in the morphology, anatomical structure and carbon/nitrogen (C/N) ratio in the axile root and LRs. LN stress increased axile root elongation, reduced the number of crown roots and decreased LR density and length. LN stress extended cell elongation zones and increased the mature cell length in the roots. LN stress reduced the cell diameter and total area of vessels and increased the amount of aerenchyma, but the number of cell layers in the crown root cortex was unchanged. The C/N ratio was higher in the axile roots than in the LRs. Maize roots acclimate to LN stress by optimizing the anatomical structure and N allocation. As a result, axile root elongation is favoured to efficiently find available N in the soil.     

Visual Signals of Individual Quality in a European Solitary Founding Paper Wasp

Conventional signals are maintained via social costs and commonly used in the animal kingdom to assess conspecifics' agonistic ability during disputes over resources. In the last decade, some experimental studies reported the existence of visual conventional signals in several social wasp species, being good rank predictors in different social contexts. Females of the social wasp Polistes gallicus do not cooperate to start nests but they often try to usurp conspecific nests. Here, we showed that the reproductive females of this species have variable facial colour patterns that function as conventional signals. Wasps with larger black spots on their clypeus are more likely to successfully overwinter, are larger, and are better at fighting and at holding a nest. Furthermore, in field experiments, resident foundresses rely on facial pattern to assess usurpers' fighting abilities, modulating their defence reaction accordingly, so that rivals with larger black spot receive more aggression than rivals with smaller or no black spots on the clypeus. Our study reveals that visual recognition abilities are widespread among paper wasps that, regardless of their social biology, face similar selective pressures within competitive contexts.     

Asymmetrical Resource Ownership Increases Owners’ and Reduces Non‐Owners’ Motivation to Fight in the Mangrove Rivulus,Kryptolebias marmoratus

Resource ownership often increases an individual's aggressiveness and its probability of defeating a competitor. Individuals contesting resource owners could therefore incur higher costs, making individuals reluctant to compete with owners. We tested the hypothesis that animals use asymmetry in resource ownership as a cue for contest costs and adjust contest decisions accordingly. Using a mangrove rivulus fish (Kryptolebias marmoratus), we staged (1) contests with a randomly assigned asymmetry in resource ownership (one fish was provided with a shelter) and (2) contests in which neither fish had a shelter. Owners that were in their shelters at the contest start showed a greater tendency to fight and won more contests than their intruder opponents; those outside the shelter at the start did not. Compared with fish in contests with no shelters at stake, shelter owners had a higher tendency to fight whether or not they were in their shelters at the start; intruders, however, had a lower tendency to fight only against owners that were inside the shelter at the start. These results demonstrate (1) that ownership status influences both owners’ and intruders’ contest decisions (and in opposite directions), producing a detectable ownership advantage and (2) that intruders required confirmation of their opponents’ ownership status before retreating without challenging them. Ownership status per se is therefore important to the fish's contest decisions.     

Hg2+对南极冰藻Chlorophyceae L-4生长和抗氧化系统的影响及藻体富集Hg2+的规律

南极冰藻Chlorophyceae L-4是南极生态系统重要的初级生产力和组成部分,其长期生长在极地环境中,有着特殊的生理机制。在生存环境和生长条件发生变化时,冰藻的膜脂系统和蛋白含量都会发生变化,而在受到重金属胁迫时,冰藻的超微结构也会发生明显变化。【目的】研究Chlorophyceae L-4在重金属离子Hg2+胁迫条件下的状态和Hg2+富集以及对其抗氧化系统的影响,为南极环境监测提供依据。【方法】绘制南极冰藻细胞在重金属离子Hg2+不同浓度胁迫条件下的生长曲线,观察其超微结构;测定丙二醛含量和SOD酶活性变化;ICP-MS法研究藻体富集Hg2+规律。【结果】Hg2+在低浓度时(≤100μg/L),细胞个数较正常条件明显偏少;在高浓度时(≥250μg/L),出现细胞死亡。丙二醛含量随Hg2+浓度升高而升高,SOD酶活性则先增强再减弱。藻体富集Hg2+在1 h达到峰值,而在Hg2+浓度持续升高时,富集量轻微降低。【结论】Hg2+离子对冰藻生长有抑制毒害作用;对Chlorophyceae L-4抗氧化系统有明显不利影响;L-4富集Hg2+在1 h内饱和,Hg2+过高时,富集量稍微降低。