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1.
科学研究证明珍珠层粉和珍珠粉物质组成和含量非常接近,如果能够制得纯正的珍珠层粉,那么就能应用在化妆品、保健品领域。本文详细介绍了珍珠层粉的几种制备方法的优缺点,提出了采取碱法制备珍珠层粉,优化工艺,制备纯正珍珠层粉的想法。  相似文献   

2.
可溶性珍珠粉制备工艺的研究   总被引:1,自引:0,他引:1  
徐向 《水产科技情报》1997,24(4):167-168
可溶性珍珠粉以珍珠为原料,经粉碎,酶水解后再活化,最后干燥精制而成。它能更充分发挥珍珠的药用功效。  相似文献   

3.
临浬县合口珍珠场是新兴的乡镇企业,建立了从孵化幼蚌到珍珠项链、珍珠粉加工的一条龙生产体系。从1980年开始养殖珍珠,产量产值不断上升,1987年产珠210公斤,全场利润30万元,1988年他们计划生产珍珠800公  相似文献   

4.
为研究壳寡糖(OCS)对珍珠龙胆石斑鱼非特异性免疫能力的影响及作用机制,实验通过在基础实验饲料中分别添加0(对照组)、200、400和800 mg/kg的壳寡糖投喂珍珠龙胆石斑鱼4周,综合分析壳寡糖对石斑鱼免疫调控作用的影响。实验首先检测了壳寡糖对鱼体内免疫及抗菌相关酶活性的影响。结果显示,投喂壳寡糖后显著提高珍珠龙胆石斑鱼谷胱甘肽过氧化物酶(GSH-Px)、溶菌酶(LZM)、过氧化氢酶(CAT)、碱性磷酸酶(AKP)、谷草转氨酶(AST)和谷丙转氨酶(ALT)的活性。其次,添加壳寡糖可显著提高珍珠龙胆石斑鱼头肾占比。为进一步探究壳寡糖对珍珠龙胆石斑鱼的免疫调控作用,本实验通过实时荧光定量PCR(qRT-PCR)检测珍珠龙胆石斑鱼头肾中免疫基因的表达情况。结果显示,壳寡糖对炎症具有双向调控作用,低剂量壳寡糖会激活炎症因子基因IL-6和IL-1β的表达,而高剂量壳寡糖会通过NF-κB途径抑制IL-6、IL-1β和TNF-α的表达。最后,通过哈维氏弧菌攻毒实验检测了壳寡糖对珍珠龙胆石斑鱼的免疫保护作用,结果显示,壳寡糖能通过NF-κB细胞通路抑制炎症因子mRNA的表达,同时显著抑制了细胞凋...  相似文献   

5.
通过对三角帆蚌外套膜上皮组织块培养和上皮细胞培养存包硬核、无包硬核的情况下的钙代谢进行比较分析,用偏光显微镜观察.结果发现,外套膜上皮组织块、上皮细胞在有硬核时与埘照的无硬核培养钙含量无明显差别,外套膜组织块经培养迁移和增值,能形成珍珠囊的上皮细胞,其结缔组织细胞共同围绕珍珠囊上皮细胞组成完整的珍珠囊.偏光显微镜下能观察到舣折射现象,表明产生由碳酸钙结晶形成的片层叠加构成珍珠质.该研究进一步探讨了体外培育珍珠(试管珍珠)的技术,为试管珍珠的研究提供了实验依据.  相似文献   

6.
淡水无核珍珠荧光光谱的研究↑(*)   总被引:19,自引:2,他引:17       下载免费PDF全文
对三角帆蚌珍珠、贝壳珍珠层及商品珍珠粉等进行了固体表面荧光测定。荧光图谱显示:在280nm激发波长下,3种样品都具有345nm和465nm的特征荧光峰,且345nm处荧光强度最大,并伴有荧光淬灭现象。这说明珍珠及其贝壳中含有色氨酸(Trp)。用5mmol/LBa(OH)2碱法水解处理从珍珠及其贝壳中提取的壳角蛋白,测得水解液的内源荧光光谱和其中Trp的含量为004%~007%。  相似文献   

7.
《水产科技情报》1976,(7):46-47
无产阶级文化大革命以来,在毛主席的无产阶级革命路线指引下,我们遵照.毛主席关于“把医疗卫生工作的重点放到农村去”和“备战、备荒、为人民”的教导,三年来,学习了广东澳头珍珠养殖场及广州市中药五厂利用马氏珍珠贝生产珍珠层粉的经验,利用淡水珍珠贝壳生产珍珠层粉代替珍珠粉供药用。并经有关部门化验,认为质量符合药检标准,成份亦与珍珠相似。在临床试验中,已取得了良好效果,获得了广大工农兵的欢迎和好评。  相似文献   

8.
三角帆蚌珍珠囊细胞的分泌活动   总被引:10,自引:0,他引:10  
本文对三角帆蚌珍珠囊细胞的分泌活动进行了亚显微结构的研究。发现珍珠囊表皮细胞能积极地进行物质合成 ,这些物质主要是蛋白质、硫酸化粘多糖和中性粘多糖 ,并将这些物质以微绒毛分泌、块状物分泌、细胞间隙分泌和大颗粒分泌等多种方式分泌到珍珠囊腔 ;而位于珍珠囊表皮细胞之间的、来源于外套膜结缔组织的腺细胞则含有丰富的中性粘多糖 ,并通过开口式分泌的方式释放到珍珠囊腔 ,同珍珠囊表皮细胞分泌的物质一起 ,共同参与珍珠结晶层的形成 ;珍珠囊细胞分泌的多样性与珍珠组成的复杂有关 ;珍珠囊细胞的分泌活动具有节律性和区段性的特点 ,这种区段性和节律性的分泌与珍珠多层结晶纤层的形成相适应。  相似文献   

9.
淡水珍珠养殖业的现状及对策   总被引:2,自引:0,他引:2  
珍珠历来被视为珍宝,又是名贵的中药材,珍珠粉为原料配制的各种化妆品和保健品,深受广大消费者欢迎。我国淡水珍珠生产出口目前仍居世界第一位,1998底淡水珍珠养殖业又呈火爆场面,但珠供过于求的形势并没有发生根本变化,要冷静分析,引导群众生产,使淡水珍珠养殖业走向健康的可持续发展的道路。1历史与现状 建国50年来,我国珍珠养殖飞速发展,特别是改革开放20年中,养殖产量成倍增长。70年代中后期,珍珠市场价格大幅度回升,育珠蚌的人工繁殖已经突破,我国的淡水珍珠产量,特别是褶纹冠蚌珍珠产量上升很快,至198…  相似文献   

10.
本刊讯2003年2月27日,常德市政府召开了珍珠产业化工作会议,这次会议是市委、市政府决定把珍珠业作为该市农业经济发展的一个重要支柱产业之后召开的第一次工作会议,市有关领导、区县(市)主管领导、畜牧水产局局长、洞庭水殖、市农产品(珍珠)大市场、珍珠协会理事和部分珍珠养殖大户参加会议。会议总结了近几年来发展珍珠的经验教训,分析国内外珍珠市场形势,研究实现珍珠产业化的路子和措施。世界珍珠协会主席何乃华先生和省畜牧水产局副局长王宇到会并作了指导性讲话。近几年常德市珍珠养殖业取得一定成绩。2002年育珠面积达1.22万公顷,比…  相似文献   

11.
12.
Previously, we reported 10 PEGE types of 85 tilapia Streptococcus agalactiae(GBS), which shifted from Streptococcus iniae in China, by using PEGE method. Presently, larger and more representative tilapia GBS were isolated, for the ?rst time in China, to characterize their serotypes and genetic diversities more precisely than had done before. 168 GBS strains were distributed in ?ve provinces of China, in which Guangdong, Guangxi and Hainan were the major ones, holding36.9%(62/168), 37.5%(63/168) and 19.6%(33/168), respectively. Serotypes, Ia, Ib and III, were observed in these strains and the most predominant one was Ia(95.2%), which mainly distributed in Guangdong, Guangxi and Hainan. Ia initially occurred in 2009, it shoot up to 32.1% in 2010,but decreased to 16.1% in 2011 before went up to 45.2% in 2012. Ib sporadically occurred during2007–2011, III onlyoccurred in 2012. 14 different PFGE types, including 4 new types(N, O,P and Q), were observed, in which B, D, F and G were the predominant types, holding 83.9%(141/168) of the total GBS strains. Ia corresponded to 11 PFGE types(A–H, N–P), in which type D predominated(51%). Ib represented 3 genotypes(I, J and Q) and III harbored only 2genotypes(N and F). Type N and Fsynchronously presented in Ia and III. In summary, the genetic diversity of tilapia GBS varied by serotypes and changed with geographical locations and years.Although Iastillpredominated, new rareserotypeIII alreadyoccurred in China.  相似文献   

13.
Growth hormone (GH) and reproduction: a review   总被引:5,自引:0,他引:5  
Interaction between growth and reproduction occurs in many vertebrates and is particularly obvious at certain stages of the life cycle in fish. Endocrine interactions between the gonadotropic axis and the somatotropic axis are described, the potential role of GH being emphasised. A comparative analysis of these phenomena in mammals, amphibians and fish, suggests a specific role of GH in the physiology of puberty, gametogenesis and fertility. It also shows the original contribution made by studies on the fish model in this field of investigations.  相似文献   

14.
The environmental processes associated with variability in the catch rates of bigeye tuna in the Atlantic Ocean are largely unexplored. This study used generalized additive models (GAMs) fitted to Taiwanese longline fishery data from 1990 to 2009 and investigated the association between environmental variables and catch rates to identify the processes influencing bigeye tuna distribution in the Atlantic Ocean. The present findings reveal that the year (temporal factor), latitude and longitude (spatial factors), and major regular longline target species of albacore catches are significant for the standardization of bigeye tuna catch rates in the Atlantic Ocean. The standardized catch rates and distribution of bigeye tuna were found to be related to environmental and climatic variation. The model selection processes showed that the selected GAMs explained 70% of the cumulative deviance in the entire Atlantic Ocean. Regarding environmental factors, the depth of the 20 degree isotherm (D20) substantially contributed to the explained deviance; other important factors were sea surface temperature (SST) and sea surface height deviation (SSHD). The potential fishing grounds were observed with SSTs of 22–28°C, a D20 shallower than 150 m and negative SSHDs in the Atlantic Ocean. The higher predicted catch rates were increased in the positive northern tropical Atlantic and negative North Atlantic Oscillation events with a higher SST and shallow D20, suggesting that climatic oscillations affect the population abundance and distribution of bigeye tuna.  相似文献   

15.
16.
Protein and amino acid composition of the mantle of juvenile O ctopus vulgaris (Cuvier, 1797) during fasting for 27 days were determined. Average protein content of octopus mantle was of 711.19 ± 46.80 g kg?1 DW, and it decreased with increasing fasting days. The non‐essential amino acids content was higher (486.18 ± 11.08 g kg?1 protein) than essential amino acids (425.82 ± 9.15 g kg?1 protein) at the start of the experiment (unstarved animals). The results suggest that the amino acid profile of the mantle where the most abundant amino acids are Arg, His, Lys, Gly, Leu and Pro could indicate a prolonged fasting condition (>20 days) or poor nutrition of O . vulgaris. This study supports the idea of using mantle for metabolic needs of starved O . vulgaris suggesting that the degradation pathway of amino acids to pyruvate and tricarboxylic acid cycle intermediates was favoured contrary to the degradation pathway of ketogenic amino acids. Special considerations should be taken concerning Thr, Ile, Ser, Ala, Asx (Asp, Asn), Glx (Glu, Gln) (because of their fast intake) and Lys and His (due to their stable contents) during a prolonged period of fasting.  相似文献   

17.
The endemic, anadromous cyprinidChalcalburnus tarichi is the only fish species known to occur in alkaline Lake Van (Eastern Anatolia, Turkey). EightC. tarichi were maintained individually in Lake Van water (17 – 19°C; pH 9.8; 153 mEq·I–1 total alkalinity; 22 total salinity) and tank water samples analyzed for 24 h in 2 to 4 h intervals. At zero time, < 1µM ammonia was present and urea was undetectable in the tank water; at 24 h, total ammonia and urea made up 114±32 and 35±25µM, respectively. Over the experimental period, ammonia-N and urea-N excretion averaged 1041±494 and 607±169moles·kg–1 fish·h–1, respectively. The extent of urea excretion was highly variable between specimens. Uric acid excretion was not detectable.Urea was present at high concentrations in all tissues and plasma (25 – 35moles·g–1·ml–1) of freshly caughtC. tarichi; total ammonia content of the tissues was by a factor of 1.9 (liver) to 3.0 (brain) lower. High arginase activity (2.4±0.2 U·min–1·g–1) was detected in the liver ofC. tarichi but ornithine carbamoylphosphate transferase, a key enzyme of the ornithine-urea-cycle, was absent. Ureagenesis is likely through degradation of arginine and/or uricolysis. High glutamine synthetase activity (11±0.6 U·min–1·g–1) and low ammonia content in brain suggest that, like other teleosts,C. tarichi has an efficient ammonia detoxification in the brain, but in no other tissue.Nitrogenous waste excretion at alkaline pH is discussed. The ability ofC. tarichi to excrete high levels of ammonia at extremely alkaline pH is unique among teleosts studied so far. The mechanism of ammonia excretion under Lake Van conditions remains to be elucidated.  相似文献   

18.
Two gonadotropins (GtH; Qa and Qb) were purified by gel filtration and ion exchange chromatography from the pituitaries of Indian walking catfish (Clarias batrachus). The presence of GtH during purification was assessed by in vitro oocyte maturation and in vivo steroidogenic activity, and their identities were determined by elution profiles, molecular weight, biological activities and yield. The molecular weights of Qa and Qb were 37 and 42 kDa, respectively, and composed of distinct subunits (Qa: 20 and 14 kDa and Qb: 26 and 18 kDa). Polyclonal antibodies raised against Qa immunostained Qa, Qb and pituitary GtH cells. A competitive Qa‐ELISA was developed whose sensitivity was 6.25 ng mL?1 (1.25 ng well?1) with intra‐ (3.5%) and inter‐ (12.4%) assay coefficients of variation. Displacement curves parallel to the standard were obtained with plasma and pituitary extracts of catfish, Qb and carp GtHII. The assay was validated by measuring the plasma Qa levels after LHRH treatment and in relation to ovarian growth in the female catfish during different reproductive phases. Based on the results, Qa and Qb corresponded to fish LH and FSH respectively. The findings will increase the knowledge of the mechanisms controlling fish reproduction and identification of sensitive phases in fish in captivity for hormonal manipulation.  相似文献   

19.
In this experiment, a feeding trial was performed to determine the effects of fructooligosaccharide (FOS) on growth performance, digestive enzyme activity and immune response of Japanese sea bass, Lateolabrax japonicus juveniles (initial weight 38.3 ± 0.5 g), and the fish were examined following feeding with six levels of FOS (0, 0.5, 1, 2, 4 and 6 g/kg) for 28 days. Significant enhancement of weight gain (WG) and specific growth rate (SGR) was found in fish fed 1 g/kg FOS incorporated diets (p < .05), while the feed conversion ratio (FCR) in the 1, 2 g/kg FOS groups reduced significantly compared with the control (p < .05). Besides, the crude lipid in the 4, 6 g/kg FOS groups increased significantly compared with the control (p < .05). On the other hand, the erepsin and lipase activities significantly elevated in intestine of fish fed 2 g/kg FOS (p < .05) and the lysozyme activity in serum of fish fed 2 g/kg FOS were significantly higher than that in the control (p < .05). Moreover, the alkaline phosphatase activities in serum of fish fed 0.5, 1, 2 g/kg FOS were significantly higher than in control (p < .05). Regression analysis showed that the relationships between dietary FOS levels and either SGR, FCR, erepsin or lysozyme activities were best expressed by regression equations, and the optimal inclusion levels are 1.37, 1.80, 3.06, 3.11, 1.93 and 1.80 g/kg for SGR, FCR, erepsin, lipase, lysozyme and total superoxide dismutase activities, respectively. Overall, this study revealed that FOS incorporated diets could beneficial for L. japonicus culture in terms of increasing the growth, digestion and immune activities. Under the present experimental condition, the optimal supplementary level of FOS in the diet of L. japonicus is 1–3 g/kg.  相似文献   

20.
Tetrahymena is a protozoan parasite, which infects guppy, Poecilia reticulata Peters, and causes substantial economical losses in commercial farms worldwide. Studies of guppy infected by Tetrahymena require standardized infection protocols. The LD50 for Tetrahymena infection of guppies by intraperitoneal (IP) injection was calibrated, and the level obtained was 946 parasites per fish. Guppy infection with Tetrahymena by immersion, imitating the natural route of infection via the integument, was studied under normal or stress conditions. Exposure to cold and netting (CNI) and to cold only (CI) followed by immersion exposure to 10 000 Tetrahymena per mL resulted in 22.5% and 19.2% mortality, respectively, as compared to 14.2% and 10% in groups that were netted only (NI) or non‐stressed (I). Histopathology revealed that immersion infection resulted in a systemic infection. Lysozyme levels, measured 3 weeks after infection, were significantly higher in the CNI group (288 μg per mg protein) compared with CI‐, NI‐ and I‐treated groups (94.5, 64 and 62.3 μg mg?1, respectively). There was no evident parasite immobilization activity in body homogenates, suggesting no development of acquired immunity. Re‐infection by IP injection revealed no increase in protection in any of the treatment groups, mortality range of 56.3–75%, higher than in the non‐exposed control (40.6% mortality).  相似文献   

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