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101.
One of the five most important global biodiversity hotspots, the Neotropical Atlantic forest supports a diverse community of birds that nest in tree cavities. Cavity‐nesting birds may be particularly sensitive to forestry and agricultural practices that remove potential nest trees; however, there have been few efforts to determine what constitutes a potential nest tree in Neotropical forests. We aimed to determine the characteristics of trees and cavities used in nesting by excavators (species that excavate their own nest cavity) and secondary cavity‐nesters (species that rely on existing cavities), and to identify the characteristics of trees most likely to contain suitable cavities in the Atlantic forest of Argentina. We used univariate analyses and conditional logistic regression models to compare characteristics of nest trees paired with unused trees found over three breeding seasons (2006–2008). Excavators selected dead or unhealthy trees. Secondary cavity‐nesters primarily selected cavities that were deep and high on the tree, using live and dead cavity‐bearing trees in proportion to their availability. Nonexcavated cavities suitable for birds occurred primarily in live trees. They were most likely to develop in large‐diameter trees, especially grapia Apuleia leiocarpa and trees in co‐dominant or suppressed crown classes. To conserve cavity‐nesting birds of the Atlantic forest, we recommend a combination of policies, economic assistance, environmental education, and technical support for forest managers and small‐scale farmers, to maintain large healthy and unhealthy trees in commercial logging operations and on farms.  相似文献   
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Tree cavities are used as shelter and breeding nests by numerous avian and mammalian species. In cold environments, tree cavities are often proposed as the best winter nest choice because of the superior protection they offer from precipitation, wind, cold temperatures, and predators. As such, they represent a critical resource, which has the potential to limit population size of non-excavating species. We assessed factors affecting site occupancy in the boreal forest by northern flying squirrels, a secondary user of tree cavities, and to identify which nest type is preferred during the colder days of the autumn–winter period. We trapped flying squirrels twice in 59 aspen-dominated stands in the autumn period using low- (1.5 m above ground-level) and high-mounted (4 m) traps to determine site occupancy. A total of 85 individuals were captured on 2,880 trap-nights. During the winter period, we radio-tracked 26 individuals to 87 diurnal nests in 220 locations. None of the habitat variables considered (cavity availability, woody debris, and lateral cover) explained site occupancy. Detectability decreased with precipitation, and was lower using high traps than low traps. Both females and males used tree cavities (26%), external nests (39%), and ground nests (35%). In cold weather, females preferred ground nests, whereas males preferred external nests. Our results do not support the hypothesis that tree cavities represent a limiting factor to northern flying squirrels in cold environments. Instead, this species seems to be a generalist and is opportunistic, using a variety of nest types. Nevertheless, practices ensuring the persistence of large diameter live cavity trees, providing better insulative properties, are likely to increase the relative use of tree cavities as nest sites by northern flying squirrels. © 2011 The Wildlife Society.  相似文献   
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目的:评价口服孟鲁司特和糠酸莫米松鼻喷剂联合治疗儿童变应性鼻炎的近期疗效,以优化儿童变应性鼻炎的治疗方案。方法:选择2011年4月~2012年4月在潍坊市人民医院耳鼻喉科就诊并确诊为变应性鼻炎的患儿48例,随机分为联合用药组(MM组,24例)和糠酸莫米松组(MS组,24例)。MM组患者给予糠酸莫米松喷鼻(早晨喷鼻1次,每次2喷),孟鲁司特片口服(5mg/次,1次/天,睡前30分口服);MS组患者给予糠酸莫米松喷鼻(早晨喷鼻2次,每次2喷)。两组的治疗疗程均为3个月,治疗后观察和比较两组患者鼻塞、鼻痒、流清涕、喷嚏等临床症状及鼻内镜的检查结果。结果:治疗1个月后,两组治疗总有效率的差异无统计学意义(P0.05);治疗3个月后,两组症状评分的改善高于1月末(P0.05);治疗3个月后,MM组的治疗总有效率显著高于MS组(P0.05)。结论:糠酸莫米松与孟鲁司特联合治疗儿童常年性变异性鼻炎的临床疗效优于单用糠酸莫米松治疗,且不良反应少。对于常年性变应性鼻炎患儿的治疗应以序贯性和个体化治疗为原则,最大程度发挥糠酸莫米松与孟鲁司特间的相互协同作用。  相似文献   
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Background: Hereditary hemorrhagic telangiectasia (HHT) is a dominantly inherited genetic vascular disorder in which epistaxis is the most frequent manifestation, responsible for high morbidity. Management of this symptom has no standard, and local treatments are often aggressive. Their efficacy is variable and has not been proven. Anti-angiogenic drugs, such as bevacizumab, are a new treatment strategy. Its systemic administration in patients with HHT improves liver damage-related symptoms and epistaxis. To limit the systemic adverse effects of bevacizumab and to ease administration, a local administration seems suitable. Primary objective: To evaluate the tolerance of increasing doses of bevacizumab administered as a nasal spray in patients with HHT-related epistaxis. Secondary objectives were to study the bioavailability and efficacy of bevacizumab against epistaxis when given as a nasal spray. Methodology: Phase 1, randomized, double-blind, placebo-controlled, monocentric study performed sequentially (dose escalation) on 5 groups of 8 patients. Each group was made up of 6 verum and 2 placebos. Five increasing doses of bevacizumab nasal spray (25 mg/mL) were evaluated: 12.5, 25, 50, 75 and 100 mg. Results: A total of 40 patients were included between October 2011 and October 2012. Bevacizumab nasal spray was well tolerated in all patients and the drug was not detected in their serum. No dose limiting toxicity was observed. No efficacy was observed at any dose in this study. Conclusion: Based on these results, bevacizumab nasal spray is a safe treatment of epistaxis in HHT. However, a randomized Phase 2 study is needed to determine its efficacy. Trial Registration: ClinicalTrials.gov Identifier #NCT01507480  相似文献   
108.
The floral ontogeny and anatomy ofKoelreuteria paniculata have been investigated to understand the developmental basis for the occurring monosymmetry and the origin of the septal cavities. Petals arise sequentially and one petal is missing between sepals 3 and 5, or rarely between sepals 2 and 5. The eight stamens arise sequentially before petal initiation is completed. The last formed petal and one stamen arise on a common primordium. Two stamen positions are empty (opposite the petal between the sepals 2 and 5, and the petal between sepal 1 and 3); consequently two antesepalous stamens have become displaced. The derivation of octandry from a diplostemonous ancestry, and reduction of the petal are discussed. The triangular gynoecium has a strong impact in obliquely reorganizing the symmetry of the flower, loss of organs, and shifts of stamens. The so-called septal slits occurring within the style are a deepreaching non-nectariferous extension of the stigma. Alternating locular furrows are present which could play a role as pollen transmitting tissue and in the loculicid dehiscence of the capsule.  相似文献   
109.
The growth of Gastrodia elata Bl. and Armillaria mellea (Vahl. ex Fr.) Quel. shares a special symbiotic relation. In general, A. mellea invades the G. elata , the epidermal cells, the cortical cells and the large cells of the growing vegetative propagation corm of G. elata . The empty cavity cells, the cork cells of the isolation in the vegetative propagation corms and the large cells of G. elata were the defensive structure, protecting the new G. elata from pathological invasion by A. mellea . In winter, G. elata enters the stage of hibernation. The faulting layer derived from the cork cells of the isolation was the last defensive structure by which new G. elata could safely live through the winter.  相似文献   
110.
探讨孢子丝菌病不典型的临床表现.孢子丝菌病是皮肤科常见的一种深部真菌病,典型的皮肤科特征是慢性肉芽肿、溃疡性损害、炎性结节等.而部分孢子丝菌病的患者由于各种各样的原因导致皮损丧失特征性临床表现,给皮肤科医生尤其是临床经验尚不丰富的年轻医师于该病的诊断带来了一定的困难.本文所讨论的8例患者均为就诊于我科门诊并已确诊为孢子丝菌病病例,皮损与典型的孢子丝菌病皮损表现不相符,希望皮肤科医师在以后的临床工作中遇到一些不典型皮损但是综合患者病史、生活环境、诊治过程等情况可考虑到此种疾病,及时给予明确的诊断,使患者能够得到及时、有效的治疗.  相似文献   
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