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1.
为了研究不同热杀菌条件对NFC冬枣汁理化性质、活性成分及抗氧化活性的影响,本文以冬枣为研究对象,设置了低温长时杀菌(75℃,5、10、15、20、25 min)和高温短时杀菌(90℃,0.25、0.50、0.75、1.00、1.50 min)两个处理,考察了NFC冬枣汁的可溶性固形物含量、pH值、总酸含量、VC含量、DPPH清除率、亚铁离子还原率等指标。研究结果表明,两种杀菌方式对NFC冬枣汁基本理化性质影响不显著(P>0.05)。相比于低温长时杀菌,高温短时杀菌的△E值更低,更能保持冬枣汁原有的色泽。两种杀菌处理后多酚、VC含量均显著降低(P<0.05),低温长时杀菌25 min后VC含量未检出,抗氧化活性也显著低于高温短时杀菌(P<0.05)。因此,通过对NFC冬枣汁品质变化的分析,发现高温短时杀菌能更好地保持原有的色泽和营养成分。 相似文献
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Haney SAMIR Kazuaki SASAKI Eman AHMED Aly KAREN Kentaro NAGAOKA Mohamed EL SAYED Kazuyoshi TAYA Gen WATANABE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(5):549-556
Although color Doppler ultrasonography has been used to evaluate testicular blood flow in
many species, very little has been done in goat. Eight male Shiba goats were exposed to a
single intramuscular injection of either gonadotropin-releasing hormone (GnRH group; 1
µg/kg BW) or human chorionic gonadotropin (hCG group; 25 IU/kg BW).
Plasma testosterone (T), estradiol (E2) and inhibin (INH) were measured just before (0 hr)
and at different intervals post injection by radioimmunoassay. Testis volume (TV) and
Doppler indices, such as resistive index (RI) and pulsatility index (PI) of the
supratesticular artery, were measured by B-mode and color Doppler ultrasonography,
respectively. The results indicated an increase in testicular blood flow in both groups,
as RI and PI decreased significantly (P<0.05), but this increase was
significant higher and earlier in hCG group (1 hr) than in the GnRH group (2 hr). A high
correlation was found for RI and PI with both T (RI, r= −0.862; PI, r= −0.707) and INH in
the GnRH group (RI, r=0.661; PI, r=0.701). However, a significant
(P<0.05) correlation was found between E2 and both RI (r= −0.610) and
PI (r= −0.763) in hCG group. In addition, TV significantly increased and was highly
correlated with RI in both groups (GnRH, r= −0.718; hCG, r= −0.779). In conclusion, hCG
and GnRH may improve testicular blood flow and TV in Shiba goats. 相似文献
4.
Hamster sperm hyperactivation is enhanced by progesterone, and this progesterone-enhanced hyperactivation is suppressed by 17β-estradiol (17βE2) and γ-aminobutyric acid (GABA). Although it has been indicated that melatonin also enhances hyperactivation, it is unknown whether melatonin-enhanced hyperactivation is also suppressed by 17βE2 and GABA. In the present study, melatonin-enhanced hyperactivation was significantly suppressed by 17βE2 but not by GABA. Moreover, suppression of melatonin-enhanced hyperactivation by 17βE2 occurred through non-genomic regulation via the estrogen receptor (ER). These results suggest that enhancement of hyperactivation is regulated by melatonin and 17βE2 through non-genomic regulation. 相似文献
5.
Yojiro YANAGAWA Yukiko MATSUURA Masatsugu SUZUKI Shin-ichi SAGA Hideto OKUYAMA Daisuke FUKUI Gen BANDO Masashi NAGANO Seiji KATAGIRI Yoshiyuki TAKAHASHI Toshio TSUBOTA 《The Journal of reproduction and development》2015,61(1):61-66
Generally, sika deer conceive a single fetus, but approximately 80% of pregnant females have two corpora lutea (CLs). The function of the accessory CL (ACL) is unknown; moreover, the process of ACL formation is unclear, and understanding this is necessary to know its role. To elucidate the process of ACL formation, the ovarian dynamics of six adult Hokkaido sika deer females were examined ultrasonographically together with peripheral estradiol-17β and progesterone concentrations. ACLs formed in three females that conceived at the first estrus of the breeding season, but not in those females that conceived at the second estrus. After copulation, postconception ovulation of the dominant follicle of the first wave is induced by an increase in estradiol-17β, which leads to formation of an ACL. A relatively low concentration of progesterone after the first estrus of the breeding season is considered to be responsible for the increase in estradiol-17β after copulation. 相似文献
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Dehydrins are proteins associated with conditions affecting the water status of plant cells, such as drought, salinity, freezing and seed maturation. Although the function of dehydrins remains unknown, it is hypothesized that they stabilize membranes and macromolecules during cellular dehydration. Red-osier dogwood (Cornus sericea L.), an extremely freeze-tolerant woody plant, accumulates dehydrin-like proteins during cold acclimation and the presence of these proteins is correlated with increased freeze tolerance (Karlson 2001, Sarnighausen et al. 2002, Karlson et al. 2003). Our objective was to determine the location of dehydrins in cold-acclimated C. sericea stems in an effort to provide insight into their potential role in the freeze tolerance of this extremely cold hardy species. Abundant labeling was observed in the nucleus and cytoplasm of cold-acclimated C. sericea stem cells. In addition, labeling was observed in association with plasmodesmata of cold-acclimated vascular cambium cells. The unique association of dehydrin-like proteins with plasmodesmata has not been reported previously. 相似文献
8.
Takao Kishimoto Tsutomu Ikeda Olov Karlsson Kengo Magara Shuji Hosoya 《Journal of Wood Science》2002,48(1):32-37
Methyl-d-xylopyranoside was allowed to react with-O-4-type quinone methide without a catalyst to elucidate the reactivities of secondary hydroxyl groups at the C2, C3, and C4 positions. Benzyl ether-type lignin-carbohydrate complex (LCC) compounds linked at the C2 and C4 positions were predominant, at a ratio of 23. However, the reactivity of the hydroxyl group at the C3 position was quite low. These results strongly suggest that the reactivity of the C2 hydroxyl group in xylan toward quinone methide intermediate is higher than that of the C3 hydroxyl group during biosynthesis of LCCs. 相似文献
9.
DNA was extracted from wood samples of six representativeCyclobalanopsis species (Fagaceae) growing in Japan that cannot be distinguished from one another by conventional microscopy. A part of the intergenic spacer region betweentrnT andtrnT 5 exon was amplified and sequenced. The sequences obtained from wood samples were grouped into three DNA types by a single nucleotide polymorphism as reported previously in leaf samples: I (Quercus acuta, Q. sessilifolia, Q. salicina), II (Q. myrsinaefolia, Q. glauca), and III (Q. gilva). Thus,Q. gilva can be distinguished from the otherQuercus species, and the others are separated in two subgroups based on DNA polymorphism. The present findings support the possibility of wood identification based on DNA polymorphism. 相似文献
10.
Takao Terashita Ryousuke Murao Kentaro Yoshikawa Jiko Shishiyama 《Journal of Wood Science》1998,44(3):234-236
Carbohydraseproduction of Hypsizygus marmoreus cultured on sawdust rice bran medium by bottle cultivation was investigated to elucidate the carbohydrase utilized as the growth substrate for the fruit-body formation of this fungus. Among the extracellular enzymes assayed, xylanase showed the highest activity. This activity greatly increased during the end of vegetative mycelial growth and fruit-body formation. Among the cellulases. CM-cellulase showed higher activity than avicelase. The activities of -1,3-glucanase, amylase, and chitinase were low. Among the intracellular enzymes, both xylanase and amylase showed higher activity levels than the other carbohydrases. In contrast, -1,3-glucanase, avicelase, and chitinase activities in mycelia were considerably lower. These results suggest that xylanase, CM-cellulase, and amylase play an important role in mycelial maturation and fruit-body growth of H. marmoreus. 相似文献