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1.
Removal of feral cats from island environments is a useful mechanism by which their ecological impact on endangered species can be reduced or ended. Nevertheless, because cats are anthropogenic in their origins, social perceptions of management practices play a large role in their implementation. Four-hundred questionnaires were delivered (386 were returned) with 100 going to each of the following: local residents; environmental workers; tourists; and, hunters. Questions explored respondents’ knowledge about island biodiversity and invasive species as well as attitudes towards cat population management methods. Habitat destruction and introduction of invasive species were considered the main threats for the conservation of island biodiversity. Most respondents considered cats to have a negative impact on biodiversity and sterilization campaigns were considered most appropriate for cat population control. Several free sterilization campaigns have been conducted in La Palma Island Biosphere Reserve in order to reduce free-ranging cats and were well received by local people. This research, which combined concepts of management, ecology and social sciences, provides valuable insights which may to be applicable on several other islands where cats and people are present and in conflict with conservation priorities.  相似文献   
2.
Fender’s blue butterfly is an endangered species restricted to fragmented, grassland remnants that are becoming increasingly dominated by tall, invasive grasses in western Oregon, USA. I performed a removal experiment to assess the impacts of structural degradation accompanying the invasion of Arrhenatherum elatius, tall oat grass, on butterfly fitness and fitness related behaviors. Clipping of A. elatius to native grass sward height resulted in 2.5–5 times as many eggs laid per leaf of host plant. Both male and female butterflies basked more frequently in areas removed of A. elatius inflorescences and upon encountering the treatment edge butterflies had a high rate of return into a large area removed of the grass inflorescences. Although butterfly behavior appeared to be affected by the change in sward height on the treatment edge, there was no evidence for the edge causing a disproportionate egg load. Invasion and dominance by A. elatius appeared to diminish host plant apparency which may result in overloading of eggs on conspicuous host plants, increased incidence of emigration, and a decrease in the likelihood of colonization because female butterflies appeared indifferent to larval resources beneath A. elatius inflorescences. Dominance of natural shortgrass prairies by tall stature grasses like A. elatius may be an insidious form of habitat degradation for grassland Lepidoptera worldwide, but it may go largely unnoticed because larval and adult resources can persist under the unnaturally tall grass canopy.  相似文献   
3.
Abstract A total of 259 Gram-negative Porphyromonas -like rods isolated from subgingival plaque samples of 16 family-owned dogs with naturally occurring periodontitis were characterized phenotypically by biochemical reactions, metabolic end products and enzymatic activities (API-ZYMTM, RoscoTM). Four distinct groups were found. Group A isolates (63) were asaccharolytic, lipase negative, trypsin positive and produced phenylacetic acid (PAA) from peptone-yeast extract glucose broth. Unlike P. gingivalis strains they were catalase positive. Group B isolates (42) differed from those of group A by a positive lipase reaction and from those of group D by failing to ferment sugars. Group C isolates (88) were asaccharolytic and did not produce PAA. They were α-fucosidase, N -acetyl- β -glucosaminidase (β-NAG) and trypsin negative, resembling P. endodontalis , but unlike human isolates, they were catalase positive. Subgroup C.1 isolates (6) differed from those of parent group C by producing minor amounts of PAA, and subgroup C.2 isolates (12) were β-NAG positive. Group D isolates (46) were weakly fermentative, lipase, catalase and trypsin positive, and produced PAA. They resembled the B. (P.) salivosus type strain which, in our hands, fermented weakly glucose, lactose and mannose. Two isolates could not be assigned to any of the previous groups.  相似文献   
4.

Background

Candida can be implicated in the pathology of chronic periodontitis.

Aims

To analyze the oral Candida carriage in patients suffering from chronic periodontitis (CP) and its correlation with the severity of this condition.

Methods

Microbiological samples were taken from 155 patients using the oral rinse (OR) technique and by using paper points in the periodontal pockets (GPP). These patients were divided into 3 groups: 89 patients without CP (control), 47 with moderate CP, and 19 with severe CP. Samples were cultured in a Candida chromogenic agar for Candida. Species were identified by microbiological and molecular methods.

Results

Candida was isolated in the OR of 45 (50.6%), 21 (44.7%), and 11 (57.9%) patients, respectively, and in the GPP of 32 (36%), 14 (29.2%), and 10 (42.6%) patients from the control, moderate CP and severe CP groups, respectively. Candida was isolated more frequently and in a greater burden in OR than in GPP (p < 0.01). Candida albicans was the most prevalent species. GPP of patients with CP had poor fungal biodiversity (p < 0.01).

Conclusions

Colonization by Candida was present in the samples of patients without CP, and with both moderate and severe CP. Nonetheless, patients with severe CP had a higher rate of Candida colonization, especially by C. albicans.  相似文献   
5.
无创产前筛查(Non-Invasive Prenatal Testing, NIPT)通过检测孕妇外周血中的游离胎儿DNA来筛查胎儿常见非整倍体,已成为产前筛查中重要的一项技术,甚至可作为高龄孕妇初步筛查的首选方式。但因为难免会出现假阴性和假阳性,所以其阴性结果也并不能总是保证胎儿正常。而对于阳性结果,需通过有创产前诊断进行验证。目前,我国临床主要采用的有创产前诊断方法有绒毛活检(Chorionic Villous Sampling, CVS)、羊膜腔穿刺(Amniocentesis, AC)和脐血穿刺。绒毛活检和羊膜腔穿刺术是NIPT阳性结果验证的主要方式。本文主要对造成NIPT假阳性和假阴性结果的原因及其阳性结果的验证进行综述。  相似文献   
6.
目的:观察4种不同的化疗方案对侵蚀性葡萄胎的疗效并进行物经济学比较。方法:回顾性分析2014年01月至2017年01月我院收治的侵蚀性葡萄胎患者76例,分为甲氨蝶呤(MTX)组、EMA-CO组、新福菌素组(ACT)、5-氟尿嘧啶(5-Fu)+新福菌素组,观察4组患者治疗后的疗效、安全性,并采用成本-效果分析方法进行药物经济学分析。结果:4组患者在年龄、治疗花费、疗效间没有差异。MTX组药费最低(5876.5±644.9元,P0.01),成本-效果比最低(286.74元),但MTX组的化疗的副反应(骨髓抑制)发生率最高;其他三组同MTX组相比,其增量成本-效果比均2000元。联合化疗方案中,EMA-CO较5-Fu+ACT组药费较低(36027.2±1792.2元vs 60215.2±3632.8元,P0.01),增量成本效果优势明显(2542.69元vs 7963.19元)。结论:对于侵蚀性葡萄胎患者,针对患者的不同情况采用联合化疗或单药化疗,其疗效均无显著性差异。MTX组治疗花费最为经济,其他组增量成本-效果较高,考虑到副反应发生率、住院天数等其他因素,其他三组仍有选择优势。  相似文献   
7.
目的探讨假丝酵母菌甘露聚糖抗原和假丝酵母菌IgG/IgM抗体、曲霉半乳甘露聚糖抗原和烟曲霉IgG抗体在侵袭性真菌病早期临床诊断中的应用价值。方法收集已确诊侵袭性假丝酵母菌病患者18例,侵袭性烟曲霉病患者6例,单纯细菌感染患者20例,浅部真菌感染患者20例,健康体检者(正常对照组)20例,通过酶联免疫吸附法(ELISA)检测患者血清甘露聚糖和假丝酵母菌IgG/IgM抗体以及曲霉半乳甘露聚糖抗原和烟曲霉IgG抗体浓度,计算各指标的灵敏度、特异度、阳性预测值、阴性预测值和受试者工作特征(ROC)曲线下面积。结果甘露聚糖抗原和假丝酵母菌IgG/IgM抗体联合测定的敏感度为66.7%,特异度为83.3%,阴性预测值为100.0%,阳性预测值为85.7%,ROC曲线下面积为0.992(95%CI:0.974~1.000);半乳甘露聚糖抗原和烟曲霉IgG抗体联合测定的敏感度为66.7%,特异度为95.0%,阴性预测值为98.2%,阳性预测值为100.0%,ROC曲线下面积为0.978(95%CI:0.934~1.000)。结论甘露聚糖抗原和假丝酵母菌IgG/IgM抗体、半乳甘露聚糖抗原和烟曲霉IgG抗体联合检测对深部真菌感染的早期诊断具有重要意义。  相似文献   
8.
Knapweeds (Centaurea spp.) are damaging invaders of grasslands and other North American rangelands. A field study was conducted to determine conditions that promote diffuse knapweed (C. diffusa) emergence and establishment in a native Colorado grassland (North America). Knapweed was planted in native grassland under treatments with different opening sizes, levels of competition, knapweed seed burial and season of seeding. There was no effect of opening size where competing natives were alive, but knapweed emergence in 5- and 15-cm openings was higher than 0-cm openings where natives were killed. Reducing competition reduced fall diffuse knapweed emergence, but did not affect spring emergence. Seed burial increased knapweed emergence, but the effect varied by season. Although diffuse knapweed emergence reached 35%, only four plants survived from 3,600 seeds. This native grassland did not prevent knapweed emergence or establishment, but both were so low that rapid knapweed invasion is unlikely.  相似文献   
9.
10.
We examined whether the residual effects on soil caused by the invasion of Carpobrotus edulis, common iceplant, would inhibit the reestablishment of a native plant species. Carpobrotus edulis interacts both directly by suppressing the growth and establishment of other plants and indirectly by altering soil chemistry. We tested whether the residual effects of C. edulis resulted in lowered germination, survival, growth, and reproduction of Gilia millefoliata, a rare dune annual. We compared G. millefoliata planted in plots previously occupied by C. edulis to G. millefoliata planted in plots that previously had native vegetation. Each plot received three treatments: seed, transplant, and unplanted, and were censused every three weeks until senescence. Carpobrotus edulis had strong negative effects on the germination, survival, growth, and reproduction of G. millefoliata. C. edulis lowers soil pH and increases organic content due to the recalcitrance of tissue to decomposition, which may have evolved as a mechanism to facilitate recolonization and invasion.  相似文献   
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