Genetic diversity,phylogenetic position and morphometric analysis of Astacus colchicus (Decapoda,Astacidae): a new insight into Eastern European crayfish fauna

The phylogeny of European crayfish fauna, especially with respect to Eastern European species, is still far from being completely resolved. To fill this gap, we analyzed most of the European crayfish species focusing on the phylogenetic position of the endemic crayfish Astacus colchicus, inhabiting Georgia. Three mitochondrial and one nuclear marker were used to study evolutionary relationships among European crayfish species, resulting in the unique phylogenetic position of A. colchicus indicating independent species status to A. astacus. Phylogenetic analyses revealed a deep molecular divergence of A. colchicus in comparison to A. astacus (6.5–10.9% in mtDNA and 1.1% in nDNA) as well as to Pontastacus leptodactylus and P. pachypus (5.5–10.0% in mtDNA and 1.4–2.4% in nDNA). Absent ventral process on second male pleopod and abdominal somites II and III with pleura rounded lacking prominent spines clearly indicate taxonomic assignment to the genus Astacus; however, the species is distributed almost in the middle of Ponto-Caspian area typical by occurrence of the genus Pontastacus. Several morphological indices linked to head length, carapace, and total body length and width were found to demonstrate apparent differences between A. colchicus and A. astacus. Although this study provides a novel insight into European crayfish phylogeography, we also point out the gaps in comprehensive study of the P. leptodactylus species complex, which could reveal details about the potential species status of particular species and subspecies within this genus.     

辽宁省糯玉米研究现状与育种方法探讨

回顾了糯玉米的起和发展状况。糯玉米起源于中国，具有广泛的利用价值。辽宁省在糯玉米的研究利用上落后于其它省份，处于起步阶段。在育种目标上应以鲜食和工业加工为主。采用二环选育法、逐代回交改良法以及回交、自交轮回式循环方法是加快辽宁省糯玉米新品种选育的有效方法。     

A comparison of the pathogenicity of two strains of hog cholera virus: 2. Virological studies

Quantitative and qualitative differences were demonstrated in the amount of virus in a range of tissues from pigs infected with either the Weybridge or New South Wales (NSW) strains of hog cholera (HC) virus. The titre of the Weybridge strain in samples, as assessed by either virus titration in cell culture or by the density of specific fluorescing cells in tissue sections, was higher than that for the NSW strain. This correlated with the greater severity of the clinico-pathological syndrome induced by the Weybridge strain. The implications of the differences in the virus content of tissues in the diagnosis of HC is discussed as is the use of monoclonal antibodies to differentiate HC and bovine virus diarrhoea viruses.     

Uterine Responses to Exogenous Oxytocin Before and After Pre-partum Luteolysis in the Cow

The aim of this study was to test the functional status of uterine oxytocin receptors in cows in vivo around parturition. The animals received consecutive, intra‐arterial injections of 800, 1600 and 3200 mU of oxytocin at three different stages: during late gestation (days 260–274), at 12 h and at 24 h after intramuscular injection of a prostaglandin F_2α analogue at day 275 to induce parturition. Cows (n=6) had been provided with myometrial electrodes and a catheter had been installed in the aorta and in a branch of the uterine vein (UV). Regular blood samples were obtained from the UV from 5 min before until 45 min after each oxytocin injection to measure plasma levels of prostaglandin F_2α (PGF_2α) and oxytocin. Uterine electromyographic (EMG) activity was registered continuously during each experiment. The increase of oxytocin levels in UV plasma after intra‐arterial injections was dose dependent (p < 0.02). Pre‐ and post treatment oxytocin levels at 24 h after induction of parturition were significantly increased (p=0.0313). Both during late pregnancy and at 12 h after induction of parturition, oxytocin caused a significant increase in EMG activity (p=0.022). After the 3200 mU dose the increase was significantly higher than with the other 2 doses (p=0.004). After each dose, EMG activity returned to baseline levels within some 15 min. At 24 h after induction of parturition, the pre‐treatment level of EMG activity had increased. Doses of 800 mU and 1600 mU of oxytocin produced a significant (p=0.022) increment of EMG activity, which was of the same magnitude as during the preceding stages; after 3200 mU of oxytocin the response was significantly higher than before (p=0.008). No significant increases of PGF_2α levels in UV plasma could be measured after oxytocin injections at any of the three stages. It is concluded that the myometrium of the pregnant cow responds in vivo to physiological doses of oxytocin. At 24 h after induction of parturition, when luteolysis has occurred and a parturient pattern of parturient myometrial activity has already started to develop, the response is enhanced. Physiological doses of oxytocin did not evoke a spurt release of PGF_2α in uterine venous blood during the peripartal period.     

计算机辅助仪器分析教学

将计算机引入仪器分析教学中,可以激发学生学习的积极性和兴趣,提高教学质量;利用分析仪器的计算机仿真技术,学生可以获得与实际操作仪器一样的经验.     

ESR法在五种植物类辐照食品检测中应用

本文以辣椒粉、干蘑菇、干红枣、核桃和螺旋藻等5种植物类食品为对象,研究了γ辐照诱导产生的ESR波谱特征,以此作为辐照产品鉴别的检测依据,并用此方法对南京辐照中心日常辐照产品进行了3年跟踪检测。结果表明:利用辐照前后ESR波谱的差异可以检测产品辐照与否。常规辐照剂量下,辣椒粉、干蘑菇、红枣辐照的正判率为100%,核桃粉和螺旋藻粉的正判率分别为80%～88%和85%～92%。ESR法在辐照产品快速鉴别和质量控制中有广泛的应用前景。     

促进区域经济发展深化图书馆信息服务

以哈尔滨市图书馆为例,通过图书馆为企业用户提供信息服务的实践,分析了图书馆为区域经济服务的现状,以及为区域经济服务过程中公共图书馆所起到的作用;提出今后图书馆促进区域经济发展、深化信息服务工作的几点举措。     

内蒙古马铃薯疮痂病发生与防治途径

2011～2012年对内蒙古自治区18个种薯生产单位和11个马铃薯县(旗、市)进行了马铃薯疮痂病(Streptomyces spp.)实地访问和调查。结果被调查的18个种薯生产单位有疮痂病率83.0%,病薯率0.0%～100.0%,11个县(旗、市)商品薯有疮痂病率100.0%,病薯率0.1%～38.0%。重复使用蛭石生产种薯、商品薯生产田轮作少、发病重。种薯较商品薯疮痂病问题更为严重。品种感病、条件适宜、重复使用蛭石、轮作少和缺乏有效杀菌剂是病害严重的主要因素。分析认为,使用效果显著的蛭石消毒剂或种薯处理剂是内蒙古马铃薯疮痂病防治的最佳途径。     

Measurement of respiratory system compliance and respiratory system resistance in healthy dogs undergoing general anaesthesia for elective orthopaedic procedures

Objective The aim of this study was to investigate normal values for the dynamic compliance of the respiratory system (Crs) and respiratory system resistance (Rrs) in mechanically ventilated anaesthetized dogs.Study design Prospective clinical study.Animals Forty healthy dogs undergoing elective orthopaedic surgery. Body weight was (mean ± SD) 26.8 ± 10.7 kg (range: 1.9–45.0 kg), age 4.7 ± 2.9 years (range: 0.1–10.6 years).Methods Dogs were premedicated with acepromazine and methadone administered intramuscularly and anaesthesia induced with propofol intravenously. After endotracheal intubation the dog's lungs were connected to an appropriate breathing system depending on body weight and isoflurane in oxygen administered for maintenance of anaesthesia. The lungs were ventilated mechanically with variables set to maintain normocapnia (end‐tidal carbon dioxide concentration 4.7–6.0 kPa). Peak inspiratory pressure, Crs, Rrs, tidal volume, respiratory rate and positive end‐expiratory pressure were recorded at 5, 30, 60, 90 and 120 minutes after start of mechanical ventilation. Cardiovascular variables were recorded at time of collection of respiratory data.Results General additive modeling revealed the following relationships: Crs = [0.895 × body weight (kg)] + 8.845 and Rrs = [?0.0966 × body weight (kg)] + 6.965. Body weight and endotracheal tube diameter were associated with Crs (p <0.001 and p =0.002 respectively) and Rrs (p = 0.017 and p =0.002 respectively), body weight being linearly related to Crs and inversely to Rrs.Conclusion and clinical relevance Body weight was linearly related to Crs while Rrs has an inverse linear relationship with body weight in mechanically ventilated dogs. The derived values of Crs and Rrs may be used for monitoring of lung function and ventilation in healthy dogs under anaesthesia.