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71.
The effect of docosahexaenoic acid (DHA) on the growth performance, survival and swim bladder inflation of larval Seriola dumerili during the rotifer feeding period was investigated in two feeding experiments. Amberjack larvae at 3 day post hatching were fed rotifers enriched with (1) freshwater C hlorella (Chlo), (2) a mixture (2:1, v/v) of Chlo and DHA‐enriched C hlorella (DHA‐Chlo), (3) DHA‐Chlo and (4) DHA‐Chlo and commercial DHA emulsion, in triplicate for 7 days. The average DHA contents of the rotifers were 0.0, 0.4, 1.0 and 1.9 mg g?1 DM respectively. The survival rate was improved by the enrichment of rotifers with DHA‐Chlo alone, and DHA‐Chlo and emulsion. Growth and swim bladder inflation of fish fed rotifers enriched with DHA‐Chlo were significantly (< 0.05) improved, however, with increased levels of DHA further improvement was not found. DHA content in the larval whole body proportionally increased with the DHA level in the rotifers. These results suggest that DHA enrichment of rotifers is effective to improve the growth, survival rate and swim bladder inflation of amberjack larvae. The DHA requirement of amberjack larvae is estimated to be 1.5 mg g?1 on a dry matter basis of rotifers.  相似文献   
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‘Niigata S3’ is a new strawberry (Fragaria × ananassa Duch.) cultivar that is early flowering and possesses high soluble solid content and good coloration. It was selected from a cross between Kei812 (seed parent) and ‘Asuka-Ruby’ (pollen parent). The first harvest date of ‘Niigata S3’ was December 27, 34 days earlier than ‘Echigohime’ and 9 days earlier than ‘Asuka-Ruby’ (means of 2007 and 2008). The marketable yield of ‘Niigata S3’ was 85% of ‘Echigohime’, 107% of ‘Asuka-Ruby’, while the early yield was 145% of ‘Echigohime’, 85% of ‘Asuka-Ruby’ (based on 2007 and 2008 means). The shape of the fruit is long conical, and its skin color medium-red. The fruit skin hardness of ‘Niigata S3’ was 31.5 g/mm2, which was harder than ‘Echigohime’, and its average soluble solid content was 11.4%, which was higher than the values for ‘Echigohime’ and ‘Asuka-Ruby’ (2008). Furthermore, ‘Niigata S3’ did not bear apical overripe fruit. This new cultivar is adaptable to the climatic conditions of Niigata, as well as other regions that experience low winter temperatures and insolation.  相似文献   
73.
AIM: To study the expression and roles of muscarinic cholinergic receptor 3 (M3R) in human small cell lung cancer (SCLC) cells. METHODS: Human SCLC cell lines SBC3 and H82 were cultured in vitro. RT-PCR and Western blotting were used to investigate the expression of M3R. MTT assay and Boyden chamber assay were carried out to determine the roles of cholinergic receptor agonist acetylcholine iodide (ACh) and M3R antagonist 4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP) in the proliferation and migration of SBC3 cells. RESULTS: M3R was expressed in SBC3 and H82 cells. The relative protein expression of M3R normalized with β-actin in SBC3 was 2.65-fold higher than that in H82. ACh stimulated SBC3 cell proliferation in a dose-dependent manner. Treatment with ACh at concentrations of 10-4 and 10-3 mol/L significantly stimulated SBC3 cell growth at 48 h and 72 h (P<0.01). SBC3 cell proliferation induced by ACh was inhibited by 4-DAMP in a dose-dependent manner. Pretreatment of the cells with 10-5 mol/L 4-DAMP suppressed the effect of ACh at 48 h (P<0.05). Pretreatment with 4-DAMP at concentrations of 10-6, 10-7 (P<0.05) and 10-5 mol/L (P<0.01) inhibited the effect of ACh at 72 h. Treatment with 10-5 or 10-6 mol/L 4-DAMP alone inhibited the cell proliferation at 48 h (P<0.01) and the inhibitory effect of 4-DAMP at concentration of 10-5 mol/L was stronger than that of 4-DAMP at concentration of 10-6 mol/L at 72 h. ACh increased the cell migration towards fibronectin (Fn) in a dose-dependent manner and ACh at concentration of 10-4 mol/L enhanced the cell migration by about 3 folds. The cell migration stimulated by 10-4 mol/L ACh was almost completely blocked by pretreatment with 4-DAMP at concentration of 10-6 or 10-5 mol/L (P<0.01). CONCLUSION: M3R is expressed in human SCLC cells. The M3R antagonist inhibits SBC3 cell proliferation and migration.  相似文献   
74.
The effects of a higher concentrate feed during the raising period on the growth and carcass of Japanese Black cattle being fattened at a younger age were investigated using three pairs of artificially bred identical twins and three pairs of full‐sibs. The animals were fed the concentrate at 2.4%/day (2.4% group) and 1.2%/day (1.2% group) comparative bodyweight (BW) during the raising period. The BW and subcutaneous fat thickness were measured every month using ultrasonic equipment. The animals were slaughtered at the age of 24 months. The BW of the 2.4% group from the age of 6–10 months appeared to be higher than that of the 1.2% group (P < 0.1). The subcutaneous fat of the 2.4% group from the age of 7–11 months was thicker than that of the 1.2% group (P < 0.1). After those ages, the BW and subcutaneous fat of the two groups did not differ and there was no difference in the carcass characteristics between the two groups. Using a higher concentrate feed during the raising period for younger fattening of Japanese Black cattle influenced growth from the late half of the raising period to the early part of the fattening period.  相似文献   
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Serotype 2 of Marek's disease virus (MDV) was isolated from apparently healthy birds belonging to genus Gallus that had no history of vaccination with MDV or herpesvirus of turkeys (HVT). Buffy-coat cells from these birds were inoculated onto chicken embryo fibroblast (CEF) cultures for primary isolation. Thirteen isolates from one golden pheasant and three white silky fowls, three black silky fowls, three Japanese long crowers, and three Japanese bantams produced herpes-like cytopathic effects (CPE) in the CEF cultures. Using serotype-specific monoclonal antibodies to MDV and HVT, 11 isolates were identified as serotype 2 MDV by indirect fluorescent antibody tests. The other two isolates were complicated with serotypes 1 and 3 of MDV-related viruses. Of 13 isolates, three cloned by the limiting-dilution method were further characterized as serotype 2 MDV biologically, genetically, and serologically. The results showed that the birds of the genus Gallus were naturally infected with serotype 2 MDV. This is the first report ever published about the distribution of serotype 2 MDV among healthy birds of the genus Gallus.  相似文献   
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