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111.
FRÉDÉRIC SÈBE THIERRY AUBIN RAYMOND NOWAK OLIVIER SÈBE GAËLLE PERRIN PASCAL POINDRON 《Bioacoustics.》2013,22(3):341-355
ABSTRACT In domestic sheep Ovis aries, the mother and the young display a preferential bond for each other that relies on multimodal inter-individual recognition. Lambs show a preference for their own dam shortly after birth, and this is important for their survival. The role of acoustic cues in this early preference for the mother is not clear. The aim of the present work was to analyze the timing of acoustic recognition of the mother and to identify the physical parameters used in the recognition of maternal bleats by the lamb. In a first study, we investigated the ability of lambs to discriminate between the bleats of their own mother and an alien equivalent mother in a two-choice test. Both ewes were hidden behind a canvas sheet and lambs were not allowed to approach the dams closer than 1 m, thus preventing visual as well as olfactory perception. Tests were conducted 12 hr, 24 hr or 48 hr after birth (n=19 or 20/group). An indication of vocal discrimination was already present at 24 hr and at 48 hr lambs spent significantly more time near their mother than near the alien dam. In a second step, we investigated which physical parameters of the bleats were important for recognition. For this, we conducted playback experiments with modified bleats at two weeks postpartum. Ours results show that lambs pay attention to a combination of various time, energy and frequency parameters: timbre (distribution of energy within the spectrum), amplitude and frequency modulations appear to be the most important parameters encoding the individual signature. We conclude that vocal recognition between the ewe and her lamb plays an important role in the display of preferential mother-young bond from very early on. Our studies also demonstrate that the encoding of the individual signature is not limited to the frequency domain but rather involves a multiparametric encoding process. 相似文献
112.
目的:观察长期家庭氧疗配合呼吸操治疗慢性阻塞性肺疾病(COPD)的临床效果。、方法:选择本院收治的COPD患者80例,随机分为研究组和对照组,各40例,两组均给予常规治疗,研究组同时由医务人员指导给予家庭氧疗和呼吸操训练,随访1年.观察两组治疗前、治疗后6个月和1年肺功能,应用StGeorge’S呼吸问卷(SGRQ)评价生存质量、结果:研究组1年内急性发作1次5人,2次2人,3次及以上1人,对照组1年内急性发作1次9人,2次7人,3次及以上4人(P〈0.05);研究组治疗后6个月、1年用力肺活量(FVC)、第1秒用力呼气容积(FEVl)和FEVl/FVC均明显升高(P〈0.05),对照组治疗后6个月、1年FVC、FEVI/FVC与治疗前比较无统计学差异(P〉0.05);研究组治疗后6个月、1年SGRQ明显降低(P〈0.05),对照组治疗后6个月、1年SGRQ与治疗前比较无统计学差异(P〉0.05).结论:家庭氧疗配合呼吸操能明显改善COPD患者肺功能,延缓患者肺功能恶化,提高患者生存质量。 相似文献
113.
目的:探讨血管细胞粘附分子-1(VCAM-1)的检测在儿童过敏性紫癜(AP)早期肾损伤中的临床意义。方法:选择明确诊断为AP 患儿85 例,均为早期无肾损害的AP病儿。根据第七版诸福棠实用儿科学有关章节的诊断标准和随访结果,进一步将研究对象分为有肾损害AP 为APN 组,无肾损害AP为AP 组,于同时间、同群体中选择健康儿童35 名为对照组。应用ELISA 法分别检测三组患儿早期无肾损害时血VCAM-1 的含量,分析血VCAM-1在儿童过敏性紫癜早期肾损伤中的临床意义。结果:APN 组血VCAM-1 水平均高于AP组和正常对照组;AP 组亦高于正常对照组,差异均有统计学意义(P〈0.01)。结论:对早期无肾损害的AP病儿,检测血浆VCAM-1 对AP发生APN 的预后诊断有重要的临床意义。 相似文献
114.
目的:脑卒中是威胁人类健康三大疾病之一,是我国成人致残的首要原因,其中80%是缺血性卒中。本文意在研究血清胆红素水平与缺血性卒中严重程度、发病机理以及颈动脉粥样硬化斑块的关系,以进一步为防治缺血性卒中的发生、发展提供新的途径。方法:选择缺血性脑卒中患者(观察组)150例和同期健康体检者(对照组)150例,分别测定两组的血清总胆红素水平(TBIL)、间接胆红素(DBIL)、直接胆红素(IBIL),并对病例组进行TOAST分型、NIHSS评分及颈部血管超声检查。比较两组间血清胆红素,及观察组内不同分型组间血清胆红素的差异。结果:缺血性卒中患者TBIL、DBIL水平显著高于正常对照组,差异具有统计学意义(P〈0.05)。缺血性卒中患者按TOAST分型各亚型间血清TBIL、DBIL、IBIL水平差异无统计学意义(P〉0.05)。中重型脑梗死组与轻型脑梗死组比较,血清TBIL、DBIL、IBIL浓度均明显升高,差别具有统计学意义(P〈0.05)。缺血性卒中患者中有动脉粥样硬化斑块形成组血清TBIL、DBIL水平低于颈部动脉内膜光滑、完整者组,差别有统计学意义(P〉0.05)。结论:缺血性卒中患者血清胆红素升高,参与急性应激反应,可能作为衡量缺血性卒中严重程度的指标之一;高水平血清胆红素可能预防颈动脉粥样硬化斑块的形成,从而预防缺血性卒中的发生。 相似文献
115.
The aim of this study was to identify the species of ked infesting dogs in the cities of central Poland. A total of 510 dogs were observed between June and September 2015. The presence of keds was noted in 182 (35.7%) animals. Keds were more prevalent in female (38.0%) than in male (33.2%) dogs, and were more frequently found in animals younger than 1 year (46.2%) and in long‐haired dogs (36.6%). The body areas most heavily colonized by keds were the groin (35.4%) and neck (21.4%). A total of 904 keds were isolated from dogs, including Hippobosca equina (Diptera: Hippoboscidae) (17.2%), Lipoptena cervi (Diptera: Hippoboscidae) (32.0%), and two species not previously encountered in Poland: Hippobosca longipennis (45.0%) and Lipoptena fortisetosa (5.9%). Hippoboscidae may act as vectors of pathogens and any shifts in their geographic range may lead to the spread of new diseases affecting animals. 相似文献
116.
117.
GAËL LE PENNEC MARCEL LE PENNEC PETER BENINGER SUZANNE DUFOUR 《Invertebrate reproduction & development.》2013,57(1-3):13-19
Summary Bathypecten vulcani is considered a relict species from the Paleozoic, based on shell characteristics such as the presence of calcite prisms. To date, it is the only pectinid species reported from hydrothermal ecosystems. Histological and ultrastructural studies show that spermatogenesis is identical to that of littoral pectinids. The spermatozoon has a 2.7 μm long pyriform head and a 40 μm flagellum. The four mitochondria of the mid-piece are about 1.2 μm in diameter. The nucleus contains dense chromatin fibres and possesses a wide, shallow (0.1 μm) anterior fossa and a narrow, deeper (0.2 μm) posterior nuclear fossa. Comparison of the ultrastructural characteristics of the spermatozoon of B. vulcani with those of littoral pectinids shows that they can be used as a diagnostic feature of this species. In particular, its acrosome characters will be a useful complement to the shell characters in the study of the phylogenetic position of this species in relation to other pectinids. 相似文献
118.