卤虫去壳卵在河蟹育苗中应用的研究

本文比较了卤虫去壳卵、无节幼体和人工合成饵料在河蟹育苗中■Ⅲ～■Ⅴ期的饵料效果,探讨了卤虫去壳卵替代无节幼体在河蟹育苗中应用的可能性。     

Low expression of mitofusin 1 is associated with mitochondrial dysfunction and apoptosis in porcine somatic cell nuclear transfer embryos

Mitochondria are necessary for the transition from oocyte to embryo and for early embryonic development. Mitofusin 1 is the main mediator of mitochondrial fusion and homeostasis. We investigated Mitofusin 1 expression levels in porcine somatic cell nuclear transfer (SCNT) embryos. The rate of blastocyst formation in SCNT embryos was reduced significantly compared with that of parthenogenetic activation embryos. SCNT embryos showed significantly decreased Mitofusin 1 expression and mitochondrial membrane potential, while exhibiting increased reactive oxygen species and apoptosis. Mitochondrial functional changes were observed in the SCNT embryos and may be correlated with low levels of Mitofusin 1 to negatively affect development.     

狐狸巴氏杆菌病病原的分离与鉴定

巴氏杆菌病又叫出血性败血症，简称出败，主要是由多杀性巴氏杆菌所引起的各种畜禽和野生动物感染的一种传染病。临床特征急性病例主要表现为败血症和炎性出血，慢性特征表现为皮下组织、关节、各脏器的局灶性化脓性炎症。该病常在畜禽中发生，而在狐狸等经济动物方面报道相对较少。2006年秋，吉林左家某狐场的狐狸突然发病并陆续死亡，经流行病学调查、病理剖检和实验室检验，确诊为多杀性巴氏杆菌感染所致。     

Effects of media,carbon sources and cytokinins on shoot organogenesis in the Christmas tree Scots pine (Pinus sylvestris L.)

Summary

Significant effects of seven basal media and three carbon sources (sucrose, glucose and fructose) on the induction of adventitious buds from embryos of Pinus sylvestris L. were observed. Moreover, hyperhydricity of expiants and shoot regenerants was observed on basal media containing fructose, especially with half-strength Murashige and Skoog (MS), MS, and woody plant medium (WPM). Expiants grown on a Gresshoff and Doy (GD) medium with sucrose produced the highest frequency of regeneration (81%) and with no hyperhydricity observed of developing adventitious shoots. Among three cytokinins tested including BA, BPA, and TDZ (at four concentrations each), 5 μM BA resulted in the highest regeneration frequency and mean number of adventitious shoots per embryo. Shoot régénérants were elongated after transfer to a GD medium containing 2 g-l_–1 activated charcoal and no growth regulators. After one month, rooting was induced on 10% of expiants.     

Introduction of normal preserving force into garment drape simulation for stable sewing process

A new force term for the particle based cloth drape simulation has been defined in this study. In the sewing process which is the starting point of a cloth drape simulation, usually large constraint forces are assigned along the sewing edges and this may generate a very stiff linear system which tends to diverge easily. Therefore, especially for a dynamic cloth simulation with a large time step, additional large damping should be introduced to stabilize the sewing process which slows down the process significantly. The new force term defined in this study was proved to be able to stabilize the sewing process without such a large damping by preserving the surface normal directions of mesh elements.     

Thermal burns of the spectacle associated with supplementary heating in native New Zealand geckos

ABSTRACT

Case history: Gradual onset of ocular opacity was observed in three gold-striped geckos (Woodworthia chrysosiretica), and five Pacific geckos (Dactylocnemis pacificus) held in two adjacent terrariums in a zoological institution located in the North Island of New Zealand. Ultraviolet light and heat had been provided for the previous 3–4 years by a fluorescent bulb, but in the last 4 weeks of winter a ceramic heat bulb had been added, situated 10?cm above the upper mesh of the cage

Clinical findings: All eight geckos presented with mostly bilateral lesions of varying severity confined to the central or upper quadrant of the spectacles. These lesions ranged from variable areas of opacity within the stroma of the spectacle to similarly distributed ulcers of the surface epithelium of both spectacles. The spectacle lesions in the Pacific geckos responded well to treatment with topical combined antimicrobial therapy, within 18–29 days. The gold-striped geckos suffered complications including dysecdysis, severe spectacle ulceration and perforation, mycotic spectaculitis, and widespread mycotic dermatitis resulting in death or leading to euthanasia.

Pathological findings: In the three gold-striped geckos, there were extensive areas of deep ulceration and replacement of the spectacle with a thick serocellular crust containing large numbers of fungal elements. The affected areas of the stroma were expanded by large deposits of proteinaceous and mucinous material, pyknotic cellular debris and moderate numbers of heterophils and macrophages as well as infiltrating fungal hyphae.

Diagnosis: Mycotic spectaculitis with ulceration and perforation, and disseminated mycotic dermatitis likely secondary to thermal burns.

Clinical relevance: This is the first report of thermal burns of the spectacle in any reptile. There was species variation in the burn severity with gold-striped geckos showing more severe lesions, possibly due to a mix of behavioural and anatomical factors. The thermal burns to the spectacles in three cases were complicated by delayed healing, perforation, dysecdysis and severe mycotic infection.     

Astrocytic purinergic signaling coordinates synaptic networks

To investigate the role of astrocytes in regulating synaptic transmission, we generated inducible transgenic mice that express a dominant-negative SNARE domain selectively in astrocytes to block the release of transmitters from these glial cells. By releasing adenosine triphosphate, which accumulates as adenosine, astrocytes tonically suppressed synaptic transmission, thereby enhancing the dynamic range for long-term potentiation and mediated activity-dependent, heterosynaptic depression. These results indicate that astrocytes are intricately linked in the regulation of synaptic strength and plasticity and provide a pathway for synaptic cross-talk.