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1.
‘Gold standard’ OIE reference PCR assay was utilized to detect the presence of infectious spleen and kidney necrosis virus (ISKNV) in freshwater ornamental fish from Malaysia. From total of 210 ornamental fish samples representing 14 species, ISKNV was detected in 36 samples representing 5 fish species. All positive cases did not show any clinical signs of ISKNV. Three restriction enzymes analyses showed that the fish were infected by identical strains of the same virus species within Megalocytivirus genus. Major capsid protein (MCP) genes of 10 ISKNV strains were sequenced and compared with 9 other reference nucleotide sequences acquired from GenBank. Sequence analysis of MCP gene showed that all strains detected in this study were closely related to the reference ISKNV with nucleotide sequence identity that was ranging from 99.8% to 100%. In addition, phylogenetic analysis of MCP gene revealed that viruses from genus Megalocytivirus can be divided into three genotypes: genotype 1 include reference ISKNV and all other strains that were detected in this study, genotype 2 include viruses closely related to red sea bream iridovirus (RSIV), and genotype 3 include viruses closely related turbot reddish body iridovirus (TRBIV).  相似文献   
2.
Thaliblastine exhibits dose dependent cytotoxic effect on HL-60, HL-60/DOX, RHE and HD-MY-2 leukemia cells. Additionally, typical for apoptosis oligonucleosomal DNA fragmentation could be detected in leukemia cells treated with thaliblastine. Moreover, an MDR-phenotype reversing effect of thaliblastine was also identified.  相似文献   
3.
The effect of gamma irradiation on the MOE of various species   总被引:1,自引:0,他引:1  
Gamma irradiation is a simple and effective method to sterilize wood and stop fungal decay. Unfortunately, little is known of the effect of this method on other properties of wood. The purpose of the present study was to establish the relationship between irradiation dosage and the elastic characteristics of wood. The longitudinal and transverse dynamic MOE of five wood species were measured periodically between subsequent irradiation phases. There was a steady decrease in MOE as gamma dosage increased, for all species included. The extent of this decrease was different between the examined species. The experimental data suggests that the MOE of lower density species decreases more sharply than that of higher density ones. Interpolation between the experimental data points shows that the necessary dose for fungal sterilization does not significantly reduce the MOE of the species involved in this study.  相似文献   
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Only a very small amount of physiological data is available about the low fertility (mean litter size is 5.7+/-0.8) of Hungarian native breed, Mangalica (M), sows. The aim of the present paper is to reveal the differences in preovulatory follicle development and intrafollicular oocyte maturation between M and Landrace (L) gilts, with special reference to the peri- and postovulatory secretion and peripheral concentrations of estradiol-17beta (E2), progesterone (P4), and luteinizing hormone (LH). The number of preovulatory follicles was 6.8+/-1.4 and 19.6+/-6.6 in M and L gilts, respectively. A lower degree of cumulus expansion and a lower percentage of mature oocytes (TI/M II) was noted in M. Higher LH and E2 peak levels, a longer E2 to LH peak interval, and lower embryo survival was confirmed. Interestingly, despite the lower number of corpora lutea, a higher peripheral blood level of P4 was shown in M than in L gilts. Both diminished follicular development and protracted oocyte maturation may be involved in low fecundity in M, and the present findings may explain these reproductive phenomena.  相似文献   
6.
This study evaluated the effect of dietary supplementation with l-tryptophan (L-TRP), a serotonin precursor, on the aggressiveness of juvenile matrinxã Brycon amazonicus. Fish were kept in individual aquaria for 7 days receiving the diets: D1 (control: 0.47% of TRP), D2 (0.94% of TRP), D3 (1.88% of TRP), and D4 (3.76% of TRP). After this, they were grouped with an intruder fish to establish a resident–intruder relationship during periods of 20 min. Blood cortisol, glucose, chloride, sodium and calcium; hemoglobin, hematocrit, red blood cell count and volume; liver glycogen and lipids were measured. Territoriality had significant effect on the aggressiveness of matrinxã (the residents were more aggressive than intruders, P < 0.001) and tryptophan significantly affected their behavior. Fish fed with the D2 diet presented a longer latency until the first attack (P = 0.0069) and bit the intruder fewer times (P = 0.0136) during the period of observation, compared to the control group. The frequency of bites and chases after the first attack was not affected by the dietary supplementation of TRP. Physiological variables were not significantly affected by the diet, except for a moderate increase in cortisol level in fish fed with D2 diet after the fight, indicating slight activation of the hypothalamus–pituitary–interrenal axis. The results show that juvenile matrinxã have aggressive and territorial behavior and that a diet containing 9.4 g TRP kg?1 alter their aggressiveness, without affecting the stress-related physiological parameters.  相似文献   
7.
CASE SUMMARY: A 5-year-old male neutered indoor cat presented for evaluation and treatment of an acute onset of nasal discharge and open-mouth breathing of 3 days' duration. He had been treated for asthma prior to presentation, but his clinical signs were more consistent with upper airway disease. Thoracic radiographs were suggestive of asthma. However, a soft tissue mass was noted in the nasopharynx on a lateral cervical radiograph. Nasopharyngeal examination revealed the mass to be a trichobezoar (hair ball) lodged in the nasopharynx, removal of which led to resolution of clinical signs. The cat re-presented with a second nasopharyngeal trichobezoar approximately 1 year later, which was also successfully removed. CLINICAL SIGNIFICANCE: Nasopharyngeal disease has myriad potential infectious, inflammatory and neoplastic etiologies. However, simpler causes such as foreign bodies can be considered in cases of acute-onset nasopharyngeal disease. To the authors' knowledge, this is the first reported case of a nasopharyngeal trichobezoar foreign body in a cat.  相似文献   
8.
Yolk sac development was investigated in 69 ovine and 10 bovine embryos from the blastocyst stage to the 7th week of gestation. Light and electron microscopical findings are reported. The yolk sac in sheep and cattle is composed of an enlarged sac-like portion lying below the embryo and two ends which follow the elongated course of the trophoblast. In sheep, an open connection exists between the intestines and the yolk sac up to a crown-rump length (CRL) of 9 mm. It is closed by 12 mm CRL. The wall of the yolk sac is especially well vascularized in the enlarged, sac-like portion. Primary erythropoiesis occurs within the blood capillaries. In the blastocyst, the yolk sac entoderm is made up of elongated, flat cells. It becomes cuboidal in the 3 mm embryo (ovine) and later columnar. The up to 20 microns tall cells stain darkly and contain numerous light-colored vesicles. At 4.5 mm CRL light cells appear between the dark ones. Both cells are rich in rough endoplasmic reticulum (rER). The increased staining of the darker cells is due to an osmophilic cytoplasm and numerous, often parallel lamella of rER. The rER of the light cells is enlarged to irregularly-shaped cisternae, which nearly fill the entire cytoplasm and give them a rounded appearance. The dark cells contain polygonal nuclei, whereas those in the light cells are round with one or two nucleoli. The oval mitochondria have only a few peripheral cristae. Golgi fields are not very common. Cells of the entoderm are connected to one another over zonulae occludentes. They possess microvilli on the luminal surface and are supported by a basement membrane. From 5 mm CRL onwards (ovine), the yolk sac entoderm folds itself between the capillaries, thereby becoming stratified. The intercellular space between the cells expands as projections between neighboring cells interlock. Canaliculi arise between adjacent epithelia. The wall of the yolk sac thickens as a result of this infolding and the densely packed capillaries. Infoldings are especially predominant in the sac-like portion of the yolk sac, and only suggested in the ends. Involution of the yolk sac begins in the peripheral end segments and proceeds centripetally. Numerous glycogen particles appear in the yolk sac entoderm cells of the ovine fetus at a CRL of 36 mm, and by a CRL of 42 mm, the sac-like portion has also begun to show signs of degeneration. Mesenchyme is very sparse within the wall of the yolk sac throughout the entire period of development.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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韩辉林  李成德 《林业研究》2007,18(2):144-146
本文报道了分布于黑龙江省塔和地区的2个中国夜蛾科新记录种:北方纬夜蛾Atrachea japonica (Leech, 1889) 和暗绿丫金翅夜蛾Autographa macrogamma (Eversmann, 1842),同时首次将以新种记述于韩国和台湾省的中文夜蛾Neustrotia rectilineata Ueda, 1987在大陆予以报道.对标本材料的外部形态特征、生殖器图片和世界性分布予以记述.所用标本材料收藏在东北林业大学林学院昆虫实验室.  相似文献   
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