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1.
在新城疫La Sota半成品检验过程中,发现接种后培养120 h的活胚,经过-20℃低温速冻1 h,有的鸡胚尿囊液中有尿酸盐产生,且出现的几率比较大,而经过2~8℃低温冷冻24 h的鸡胚,产生白色尿酸盐的几率相对小一些。凡是有尿酸盐产生的鸡胚,均没有血凝现象产生。但用含有尿酸盐的尿囊液接种鸡胚,继续增殖,会有病毒大量复制,试验说明有新城疫病毒存在的尿囊液中,若有尿酸盐沉淀,则血凝现象会被遮盖。  相似文献   
2.

Introduction  

Sediments from urban stormwater runoff have been collected and analyzed for the content of various contaminants in harbor areas of Harstad, Trondheim, Bergen, and Drammen, Norway.  相似文献   
3.
Melatonin, the major secretory product of the pineal gland, scavenges a variety of reactive oxygen and nitrogen species in vivo and in vitro, indicating that melatonin is a potent function as an antioxidant. The objective of this study was to investigate the effect of melatonin in the presence or absence of hydrogen peroxide (H2O2) on sperm characteristics (motility, viability, survival rate, membrane integrity, lipid peroxidation (LPO) and mitochondria activity) and also to examine the developmental rates to the blastocysts stage of porcine oocytes fertilized in vitro with semen treated with or without melatonin (100 nm ) in the presence or absence of H2O2 (250 μm ). The sperm were treated with melatonin in the presence or absence of H2O2 for 3, 6, 9 and 12 h at 37°C and then analysed for the sperm characteristics. The porcine embryos were produced by in vitro maturation and in vitro fertilization (IVM/IVF) using semen treated with or without melatonin (100 nm ) in the presence or absence of H2O2 (250 μm ) for 6 h. The semen characteristics, including motility, viability, survival rate, membrane integrity and mitochondria activity, were higher in the groups that were treated with melatonin in comparison to other groups, irrespective of incubation periods. Malondialdehyde levels in control, melatonin and melatonin + H2O2 groups were lower than H2O2 only group. A positive correlation was shown among motility, viability, survival rate and membrane integrity, but a negative correlation was observed between LPO and the other evaluation methods. The developmental rates to blastocysts of IVM/IVF porcine oocytes fertilized by semen treated with melatonin were significantly increased compared with any other groups, with the cell number of blastocysts shown to have a similar trend to the developmental rates. These results demonstrate that melatonin can improve the semen characteristics during in vitro storage and support the developmental ability of IVM/IVF embryos in pigs.  相似文献   
4.
The aim of the present study was to elucidate the fundamental mechanism of bovine oviduct epithelial cell (BOEC) co‐culture on developmental capacity of bovine in vitro oocyte maturation/in vitro fertilization (IVM/IVF) embryos. We examined the effects of astaxanthin against nitric oxide‐induced oxidative stress on cell viability by MTT assay, lipid peroxidation (LPO) by using thiobarbituric acid (TBA) reaction for malondialdehyde (MDA) and the expression of antioxidant genes (CuZnSOD, MnSOD and Catalase) or apoptosis genes (Bcl‐2, Caspase‐3 and Bax) by RT‐PCR in BOEC. We also evaluated the developmental rates of bovine IVM/IVF embryos co‐cultured with BOEC pre‐treated with astaxanthin (500 μm ) in the presence or absence of sodium nitroprusside (SNP, 1000 μm ) for 24 h. Cell viability in BOEC treated with SNP (50–2000 μm ) lowered, while astaxanthin addition (50–500 μm ) increased it in a dose‐dependent manner. Cell viability in astaxanthin plus SNP (1000 μm ) gradually recovered according to the increase in astaxanthin additions (100–500 mm ). The LPO in astaxanthin group (50–500 μM) gradually decreased in a dose dependent manner and among SNP or astaxanthin plus SNP group, SNP alone and astaxanthin (50 μM) plus SNP shown a significant increase than other groups (p < 0.05). Expression of apoptosis or antioxidant genes was detected by RT‐PCR. Bcl‐2 and antioxidant genes were detected in astaxanthin or astaxanthin plus SNP group, and Caspase‐3 and Bax genes were only found in SNP group. When bovine IVM/IVF embryos were cultured for 6–7 days under co‐culture system such as BOEC treated with astaxanthin in the presence or absence of SNP, the developmental ability to blastocysts in 500 μm astaxanthin group was the highest of all groups. These results suggest that astaxanthin has a antioxidative effect on cell viability and LPO of BOEC, and development of bovine IVM/IVF embryos due to the induction of antioxidant genes and suppression of apoptosis genes.  相似文献   
5.
Bacillus subtilis has only seldom been associated with pathological conditions in mammals. As the organism is considered to be ubiquitous in the environment, care has to be taken not to put too much emphasis on the pathogenicity of the organism, even in cases where it is isolated in pure culture. Bacillus subtilis was isolated from 17 cases of bovine mastitis in which it was considered to be the etiological factor.  相似文献   
6.
The effect of diurnal variations in air humidity and temperature under continuous lighting period (LP) on growth, flowering and water loss were studied in two pot-rose cultivars.  相似文献   
7.
Tritrichomonas foetus was found in the uterus of a cat with pyometra and in the faeces of three other cats in the same household, one of which had chronic diarrhoea. This is the first report of a feline uterine infection with T. foetus and also the first time T. foetus has ever been diagnosed in animals in Norway. The diagnosis was made by microscopic examination and sequencing studies.  相似文献   
8.
9.
The pigmentation and corresponding in vivo and in vitro absorption characteristics in three different deep-water coral species: white and orange Lophelia pertusa, Paragorgia arborea and Primnoa resedaeformis, collected from the Trondheimsfjord are described. Pigments were isolated and characterized by High-Performance Liquid Chromatography (HPLC) analysis and High-Performance Liquid Chromatography Time-Of-Flight Mass Spectrometer (LC-TOF MS). The main carotenoids identified for all three coral species were astaxanthin and a canthaxanthin-like carotenoid. Soft tissue and skeleton of orange L. pertusa contained 2 times more astaxanthin g(-1) wet weight compared to white L. pertusa. White and orange L. pertusa were characterized with in vivo absorbance peaks at 409 and 473 nm, respectively. In vivo absorbance maxima for P. arborea and P. resedaeformis was typically at 475 nm. The shapes of the absorbance spectra (400-700 nm) were species-specific, indicated by in vivo, in vitro and the corresponding difference spectra. The results may provide important chemotaxonomic information for pigment when bonded to their proteins in vivo, bio-prospecting, and for in situ identification, mapping and monitoring of corals.  相似文献   
10.
Plants of cucumber (Cucumis sativus L. cv. Euphorbia) were grown in a traditional high-wire cultivation system to investigate the effects of three lighting regimes on photosynthetic characteristics, leaf area and yield. The lighting regimes included overhead lighting (OH), where all the lamps were mounted above the canopy and overhead + intracanopy lighting (OH + IC) which comprised 65% of overhead lamps and 35% of lamps mounted vertically along the plant rows. All overhead lighting was provided for 20 h day−1 and intracanopy lighting was provided for either 20 h or 24 h day−1 lighting period. Intracanopy lighting improved the light distribution in the canopy. Gas exchange measurements showed that intracanopy lighting increased net photosynthesis (PN) and photosynthetic capacity (Pmax). Parameters calculated from CO2 response (A/Ci) curves showed that in vivo estimate of the maximum rate of Rubisco carboxylation (Vcmax) and the maximum rate of electron transport (Jmax) were affected by light regime. Intracanopy light increased yield by 11% compared to traditional overhead light.  相似文献   
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