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广东大鹏湾虾拖网网囊网目选择性研究 总被引：2，自引：4，他引：2
虾拖网渔业是南海海域重要的作业方式之一,但尚未有关该渔业网目尺寸选择性的报道。为评价虾拖网渔具的渔获性能、合理利用虾类资源,在广东大鹏湾进行了网目选择性试验。试验采用双支架虾拖网作为试验网具,并使用套网法估算了网目内径为35、40和45 mm的网囊对主捕虾类的选择性。结果显示,虾类渔获中刀额新对虾、须赤虾、周氏新对虾和日本囊对虾渔获数量较多,比较以往资料,刀额新对虾和周氏新对虾优势体长、平均体长均有所下降,其它2种虾类平均体长未见明显变化;选择性分析结果显示,主捕虾类的L50随网目尺寸线性增大。根据试验结果并结合历史资料,笔者认为现阶段35 mm的网囊网目尺寸对于保护上述4种虾类资源是比较合适的。 相似文献
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Hideo Sakaji 《Fisheries Science》2001,67(3):444-448
SUMMARY: Seasonal changes in the percentage of mature female Metapenaeopsis dalei were studied histologically, and the annual cycle of maturation and spawning of this species was discussed. Specimens were collected at night by a beam trawler in Tosa Bay (33°N, 133°E) during the period from April 1995 to March 1996. All individuals had a gonado somatic index [ GSI = 100 (gonado weight/body weight)] of higher than 8, and 66.7% of those individuals with a GSI of 6–8 had oocytes in the late phase of the prematuration stage after germinal vesicle shrinking and migrating to the margin of the oocyte or had oocytes in the maturation stage. Such individuals with developed oocytes appeared in April, June, July, August, October, November and March. Individuals with a GSI above 6 appeared throughout the year, except during September and February. Individuals with ovulated oocytes were sampled in March when the water temperature near the bottom depths was lowest (15.4°C) during the year, being similar to February (15.1°C). These facts indicate that maturation occurs all year-round and suggests that spawning in the Metapenaeopsis dalei population in Tosa Bay occurs all year-round. This is the first report of year-round maturation in penaeid shrimps in Japanese waters. 相似文献
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AIM:To study the effects of Scutellaria barbata flavonoids (SBF) on abnormal expression of nitric oxide synthase (NOS), heat-shock protein 70 (HSP70) and apolipoprotein E (apoE) induced by Aβ 25-35 in rat astrocytes. METHODS:The third generation of cultured rat astrocytes was divided into 5 groups. The cells in 3 drug treatment groups were given SBF at dose of 17.5 mg/L, 35 mg/L and 70 mg/L for 24 h, and then the cells in model group and 3 doses of SBF groups were exposed to Aβ 25-35 at concentration of 100 μmol/L for 24 h. The expression of endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS) and neuronal nitric oxide synthase (nNOS) in the cultured cells was assayed by immunohistochemical method. The expression of HSP70 was estimated by Western blotting and the mRNA expression of apoE was assessed by RT-PCR. RESULTS:Compared with control group, the protein level of eNOS were significantly decreased and the protein level of iNOS increased (P<0.01) in model group. The protein expression of HSP70 and mRNA expression of apoE were notably increased (P<0.01) in model group. However, these disturbances were attenuated by SBF at dose of 17.5, 35 and 70 mg/L (P<0.01). CONCLUSION:SBF has an obvious protective effect on damaged astrocytes induced by Aβ 25-35, suggesting that SBF may be helpful for the treatment of Alzheimer disease. 相似文献
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李林轩袁袁林伟袁李翠袁韦丽勤袁李荣峰袁韦坤华 《广东农业科学》2014,41(2):38-40
药用植物半枝莲是一种应用范围广使用量大和药效功能多的传统中药,近年研究表明其还具有良好
的抗肿瘤作用,研究了不同激素及添加量对半枝莲继代培养和生根培养的影响,结果表明院不同的细胞分裂素和生
长素比例对半枝莲继代培养的影响不同半枝莲继代培养最适培养基为MS+6-BA 1.0 mg/L+NAA 0.2 mg/L+IAA 0.2
mg/L,不同的细胞分裂素和生长素比例对半枝莲根的生长影响也不同,半枝莲壮苗生根最适培养基为1/2MS+ NAA
1.0 mg/L+IBA 0.2 mg/L。 相似文献
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AIM：To study the abnormalities of Bcl-2, Bax, Bcl-xL and Bax in the cell mitochondrial membrane of cerebral cortex in the rats injected with β-amyloid beta protein 25-35 (Aβ25-35) in combination with aluminum trichloride (AlCl3) and recombinant human transforming growth factor β1 (rhTGF-β1) (composite Aβ25-35) into lateral cerebral ventricle, and to explore the intervention of Scutellaria Barbata flavonoids (SBF). METHODS：The male SD rats were used to establish the neuronal damaged model by receiving injection of RhTGF-β1 1 μL (10 ng) on day 1 of operation, and then from day 2 of operation, intracerebroventricular injection of Aβ25-35 (4 μg/d, consecutive 14 d) in the morning and 1% AlCl3 in the afternoon (3 μL/d, consecutive 5 d). On the day 49 of operation, the successful model rats were randomly divided into model control and 3 doses of SBF groupss. The rats in SBF groups were daily orally administered with SBF at doses of 35, 70 and 140 mg/kg for 36 d. All the rats were decapitated 60 min after the last administration. The protein expression of Bcl-2, Bax, Bcl-xL and Bak in rat cerebral cortex cell mitochondrial membrane was detected by Western blotting. RESULTS：The composite Aβ25-35 dramatically caused decreases in Bcl-2 and Bcl-xL (P<0.05), and increases in Bax and Bak (P<0.01) in rat cerebral cortex cell mitochondrial membrane. However, oral treatment with SBF for 36 d reversed the above disorders induced by composite Aβ25-35. CONCLUSION：The composite Aβ25-35 induces the expression abnormalities of Bcl-2, Bax, Bcl-xL and Bak in mitochondrial membrane and SBF reverses the above disturbances of apoptotic factors. 相似文献
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Johnson RS Sangster CR Sigler L Hambleton S Paré JA 《Australian veterinary journal》2011,89(12):515-519
Deep fungal dermatitis caused by the Chrysosporium anamorph of Nannizziopsis vriesii (CANV) was diagnosed in a group of coastal bearded dragons (Pogona barbata). The outbreak extended over a 6-month period, with four of six lizards from the same zoological outdoor enclosure succumbing to infection. A fifth case of dermatomycosis was identified in a pet lizard originally sourced from the wild. Diagnosis of infection with the CANV was based on similar clinical signs and histopathology in all animals and confirmed by culture and sequencing of the fungus from one animal. This is the first report of the CANV causing disease in a terrestrial reptile species in Australia and the first in the coastal bearded dragon. 相似文献
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以茎尖为外植体进行了离体快繁研究。利用6-BA×IBA和6-BA×NAA两种激素组合诱导丛生芽,6-BA×IBA激素组合的最佳增殖培养基是MS+6-BA0.5 mg/L+IBA0.1 mg/L,增殖系数可达6.5;6-BA×NAA激素组合的最佳增殖培养基是MS+6-BA0.5 mg/L+NAA0mg/L,增殖系数可达6.1;两种组合无显著性差异。在MS基本培养基上即可生根且长势良好,生根率为100%;诱导丛生芽试验中6-BA浓度不能超过0.5 mg/L,否则会有愈伤组织出现。 相似文献
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半枝莲花粉母细胞减数分裂观察及核型分析 总被引：2，自引：0，他引：2
应用压片法对药用植物半枝莲的花粉母细胞减数分裂过程和核型进行了研究,结果表明:半枝莲绝大多数花粉母细胞减数分裂过程中染色体的行为正常,终变期可形成13个二价体,其减数分裂为同时型;花粉粒育性为98.4%;半支莲的染色体数目为2n=2x=26,核型公式为K(2n)=2x=26=20m+4sm+2st,染色体长度范围为1.49～4.24 μm,染色体相对长度组成为2n=8S+8M1+4M2+6L,其核型为"2B"型,从染色体水平证明半枝莲在系统演化上属于较进化的种类. 相似文献