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81.
82.
The biochemical and gel properties of Pacific sardine and Pacific mackerel were characterized as affected by preparation and cooking methods. Four to eight times more salt soluble proteins were extracted from water-washed paste than fish protein isolate (FPI) paste. Higher total sulfhydryl content was measured in FPI, indicating the exposure of sulfhydryl groups during alkaline extraction. Comparing gel properties based on two cooking methods (slow and fast), the two pelagic fish proteins performed quite differently. Heating rate did not differentiate between surimi and FPI gels from sardine. However, mackerel exhibited higher texture values when using the fast cooking method, indicating the presence of high levels of proteolytic enzymes. Water-washed surimi gels were whiter than FPI for both species. Water retention ability appeared to be higher with mackerel than sardine, regardless of isolation and cooking method. Sodium dodecyl sulfate polyacrylamide gel eletrophoresis (SDS-PAGE) also supported a difference in processing chemistry and thermal behavior between two methods for protein isolation and cooking, respectively. 相似文献
83.
扇贝多肽对氧化所致胸腺细胞凋亡的影响 总被引:9,自引:0,他引:9
观察扇贝多肽(Polypeptide from Chlamys ferreri)(PCF)对实验性氧化所致小鼠胸腺细胞凋亡的影响。采用台盼蓝(Trypan Blue)活细胞拒染法在普通光学显微镜下观察细胞的存活率;以四甲基氮唑盐(MTT)法测定细胞的增殖活性;以生化检测(DNA ladder)法观察PCF对细胞DNA片断化的影响;用透射电镜观察细胞的超微形态结构变化。台盼蓝染色法证实PCF能增强细胞的活性并与PCF浓度成正比;MTT法表明PCF不仅能保护细胞免受损伤,而且还能促进细胞的增殖,并有PCF依赖性;生化检测显示PCF能减少细胞凋亡的DNA片断化数目;细胞的超微结构还表明PCF能维持细胞结构的完整性。PCF可明显抑制实验性氧化损伤小鼠胸腺细胞的凋亡并有药物依赖性,而且明显优于维生素C。 相似文献
84.
研究分析了唇(鱼骨)(♀)×花(鱼骨)(♂)杂交育种的特点和可行性.结果表明:2008-2011年,共计获得约164万粒受精卵,杂交F1鱼苗111.7万尾.在水温18~26℃条件下,唇(鱼骨)(♀)×花(鱼骨)(♂)的催产率、受精率和孵化率可达到85.5%~89.2%、80.6%~81.2%和80%~85.6%.在水温(20±1)℃条件下,杂交F1受精卵在受精后94 h 10 min,仔鱼开始出膜.初孵仔鱼全长5.75 ~ 6.83 mm.杂交F1成鱼的体色和体型与母本比较相近.唇(鱼骨)(♀)×花(鱼骨)(♂)的杂交育种是可行的. 相似文献
85.
Jeong-Chae Park Jeong-Hoon Lee Keita Kodama Hiroshi Urushitani Yasuhiko Ohta Toshihiro Horiguchi 《Fisheries Science》2013,79(2):203-211
We conducted histological observation of male germ cells and reproductive organs of the starspotted smooth-hound Mustelus manazo in Tokyo Bay to reveal any abnormality in male reproductive traits, as part of a study to elucidate the factors causing recent fluctuation in abundance of the population. Spermatogenesis proceeded in spermatocysts from the germinal zone in the ventral part of the testis to the degenerative zone in the dorsal part, where the spermatozoa were conveyed into the ciliated lumina of the attached terminal branches of the intratesticular ducts. The intratesticular ducts were classified from their terminal ends into branch, stem, and collecting tubules. The ducts formed in the germinal zone and grew as the spermatocysts developed. An opening formed through the wall of each of the most mature spermatocysts into a branch tubule; bundles of spermatozoa were evacuated through this opening into the branch and then the stem tubule and subsequently into the collecting tubules in the rete testis and the efferent duct connected to the epididymis. Spermatocysts that were unable to emit sperm because of failure of adhesion to the branch tubules were disorganized in situ, as were their spermatozoa. The collapsed spermatocysts seem to be cleared by hemophagocytosis with lymphocytes and leukocytes, which may have been recruited from the epigonal organ. There were no specific abnormalities in the spermatogenesis or the morphological structure of testes, which suggested that an abnormality of male reproductive traits was not the major cause of the recent fluctuation in the population abundance of this species. Details of the intratesticular duct system for sperm emission to the epididymis are the first findings in elasmobranchs worldwide. 相似文献
86.
Seung-Taek Oh Oh-Jin Kwon Byoung-Chul Chun Jae-Whan Cho Jong-Shin Park 《Fibers and Polymers》2009,10(1):21-26
We produced a protein loaded, pH-sensitive alginate-bentonite hydrogel for wound dressings. Alginate is a nontoxic polysaccharide
with favorable pH-sensitive properties that make it useful for the intestinal delivery of protein drugs. However, the use
of alginate for drug delivery is limited by drug leaching and rapid dissolution of alginate at the higher pH, which may result
in lower entrapment efficiency and a burst in the release of entrapped protein drugs. To overcome these problems, we created
a novel cross-linked alginate-bentonite hydrogel by combining mineral-rich bentonite with the alginate matrix along with an
additive to ensure controlled release. We analyzed the gel in the drug loading process in an aqueous environment by looking
at the release profiles of a model protein drug (BSA) from the hydrogel at pH values of 4.5, 5.2 (skin area) and 7.4, 9.2
(wound area). The swelling ratio decreased with bentonite concentration, but did not fall below 6. The rate of drug release
was slowest at a pH value of 4.5 and fastest at a pH value of 9.2. The rate of drug release decreased with bentonite concentration.
The presence of bentonite prevents the rapid dissolution of alginate at the higher pH, ensuring the controlled release of
the entrapped drug. 相似文献
87.
我国林木生物质能源十分丰富,适宜发展林木生物质发电产业。但是目前林木生物质发电产业仍处于初级发展阶段,产业发展模式还不够成熟,产业潜力未被充分挖掘。文中基于产业模式相关研究基础,结合我国林木生物质发电产业发展实践,设计了更为全面系统的林木生物质发电产业发展模式,根据政府对产业发展介入力度不同,将产业发展模式分为萌芽期(政府主导型产业发展模式)、成长期(政府引导型产业发展模式)、成熟期(政府规制型产业发展模式),并从资源、经济、社会、环境、技术5个方面论证林木生物质发电产业发展的可行性、有效性和持续发展的稳定性,以期为国家主管部门制定相关政策提供理论参考。 相似文献
88.
89.
Kwangho Choi Chung Il Lee Kwangseok Hwang Sang-Woo Kim Jong-Hwa Park Yeong Gong 《Fisheries Research》2008,91(2-3):281-290
Data on squid catches of Korean and Japan, water temperatures at depth of 100 m, and night-visible images of fishing boats collected in the East (Japan) Sea from 1970 to 1999 were analyzed to examine the distribution and migration of the Japanese common squid, Todarodes pacificus, in the southwestern part of the East (Japan) Sea. The main fishing grounds detected from squid catch in each grid (0.5° latitude × 0.5° longitude) by Korean squid fishery and night-visible images provided by the Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS) were situated in the southwestern part of the East (Japan) Sea. The distribution and migration route was illustrated from squid catch in each grid and DMSP OLS image. In years of high catches, the fishing grounds were situated mainly between Ulleung Island and the eastern coastal waters of Korea, while in years of low catches they were situated between Ulleung Island and the Yamato Bank in the central East (Japan) Sea. The center of fishing activity began moving northward from around the Korea/Tsushima strait to the northern boundary of the Tsushima Warm Current in March, reaching into the Yamato Bank in September, and then returning to the strait by February. The northward and southward migration routes differed; the northward migration route occurred closer to the mainland coast of Korea than the southward migration route did. This work suggests T. pacificus begin their northward migration almost 2 months earlier than previously suggested. 相似文献
90.
Inja Yeon Mi Young SongMyoung Ho Sohn Hak Jin HwangYang Jae Im Do Hoon KimHee Won Park Chang Ik Zhang 《Fisheries Research》2011,112(3):179-188
Landings in the blue crab, Portunus trituberculatus, fishery in Korean waters of the Yellow Sea have declined substantially from 11,000 t in the 1980s to 2,300 t in 2004. Blue crab habitat quality in the Yellow Sea has been degraded by anthropogenic activities including sand mining, land reclamation, and coastal pollution. Various traditional management measures have been implemented, including closed seasons during spawning and size limits, but these measures alone have been unsuccessful to conserve blue crab stocks. Consequently, a total allowable catch and a stock-rebuilding program using an ecosystem-based management approach were implemented in 2003 and 2006, respectively to rebuild blue crab stocks and restore habitats. This program involved assessment of both blue crab stock status and trammel-net fishery impacts at an ecosystem-level using an ecosystem-based fisheries assessment method (
[Zhang et al., 2009] and [Zhang et al., 2010]), which considered fishery data from catch and effort time-series, crab population biology, and ecosystem characteristics, including habitats and environmental conditions. Recent (2008) management status indices have shown significant positive change compared to conditions in 2000 with respect to sustainability of the stock and fishery and with regards to biodiversity and ecosystem habitat quality. 相似文献