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91.
Comparison of in vitro vitellogenin synthesis among different nonylphenol products using primary cultures of tilapia hepatocytes 总被引:1,自引:0,他引:1
Effect of nonylphenol (NP) products from different companies on in vitro vitellogenin (VTG) synthesis was compared using tilapia ( Oreochromis mossambicus ) hepatocytes cultures. Addition of NP at a concentration of 10−3 M to the medium caused death of hepatocytes (NP-A and NP-B) and delay of monolayer formation (NP-C). No cell death was observed at a concentration of 10−4 M (NP-A, -B and -C) but cell adhesion was slower than control. These results suggest that high concentration of NP is toxic against tilapia hepatocytes. When effects of estradiol-17β (E2 , 10−7 M) and NP (10−4 M) on in vitro VTG synthesis were examined, addition of E2 and NP-A and NP-B to the media resulted in elevation of VTG. NP-C did not induce VTG in the medium. Co-treatment of NP-B and tamoxifen, a non-steroidal anti-estrogen, reduced VTG synthesis. These results suggest that NP has estrogenic potential in primary cultures of tilapia hepatocytes and acts through binding to the estrogen receptor, and that there is a difference in the induction level of VTG among different NP products. 相似文献
92.
不同生长环境下水稻结实率数量性状位点的检测 总被引:4,自引:0,他引:4
以籼稻密阳23与粳稻吉冷1号配制所获得的F2:3群体200个家系作为作图群体,在北京、昆明、三亚、公主岭和韩国春川等5个点进行水稻结实率的鉴定,并利用SSR标记对水稻结实率数量性状位点进行检测。结果表明,水稻结实率表型值及其在F3家系群中的分布以及所检测到的QTL数目因生长环境不同而有较大差异,说明QTL与环境有明显的互作效应。水稻结实率在F3家系群中呈接近正态或偏态的连续分布,是多个基因所控制的数量性状。共检测到与水稻结实率相关的QTL 14个,分布于第1、2、3、4、6、7、8、10和12染色体上,对表型变异的贡献率为4.9%~15.3%。分别位于第1、2、6和12染色体RM1~RM259、RM263~RM6、RM340~RM30、RM270~RM17区间的qSSR1、qSSR2、qSSR6和qSSR12至少在2种生长环境下均检测到,对表型变异的贡献率分别为4.9%~8.4%、4.8%~7.2%、7.6%~10.7%和7.4%~10.4%。以上多数QTL增效等位基因均来自吉冷1号,基因作用方式主要为部分显性或显性或超显性。 相似文献
93.
Stochasticity dominates assembly processes of soil nematode metacommunities on three Asian mountains
Shuqi ZOU Jonathan ADAMS Zhi YU Nan LI Dorsaf KERFAHI Binu TRIPATHI Changbae LEE Teng YANG Itumeleng MOROENYANE Xing CHEN Jinsoo KIM Hyun Jeong KWAK Matthew Chidozie OGWU Sang-Seob LEE Ke DONG 《土壤圈》2023,33(2):331-342
Nematodes play an important role in ecosystems; however, very little is known about their assembly processes and the factors influencing them. We studied nematode communities in bulk soils from three Asian mountain ecosystems to determine the assembly processes of free-living nematode metacommunities and their driving factors. On each mountain, elevations span a range of climatic conditions with the potential to reveal assembly processes that predominate across multiple biomes. A phylogenetic nu... 相似文献
94.
Two-phase flow in a horizontal pipe was investigated by using numerical and experimental visualization methods.A horizontal pipe was built for qualitative and quantitative flow visualization.The length of horizontal pipe flow system was 9.5 m and the inner diameter was 51 mm.High-speed video method was used for the qualitative visualization and PIV method was applied for the quantitative visua-lization.The same geometry model was used for the numerical study.Three flow regimes including stratified flow,elongated bubble and slug flow field were generated and visualized by using numerical and experimental methods.The results show that the numerical simulation results are qualitatively si-milar to that of the experimental results.In addition,more quantitative results can be analyzed by numerical method.Development and decay process of slug flow was investigated,showing that the decay of slug heavily depends on the magnitude of nose velocity and its lasting time.It can also be found that the liquid superficial velocity plays a significant role in affecting the slug frequency.When keeping the gas superficial velocity constant,the frequency will increase with the liquid superficial velocity. 相似文献
95.
番茄果实颜色形成的分子机制及调控研究进展 总被引:1,自引:0,他引:1
番茄果实颜色主要包括绿色、黄色、红色、粉色和紫色等,这些颜色的形成是叶绿素、类胡萝卜素、番茄红素、黄酮类化合物等多种次生代谢物质积累综合呈现的结果。针对近年来关于控制番茄果实颜色形成的相关基因、生物合成途径及其调控机制的研究进展进行综述,旨在为今后通过生物技术手段进行番茄果色农艺性状改良提供参考。 相似文献
96.
The effects of a range of herbicide doses on crop:weed competition were investigated by measuring crop yield and weed seed production. Weed competitivity of wheat was greater in cv. Spark than in cv. Avalon, and decreased with increasing herbicide dose, being well described by the standard dose–response curve. A combined model was then developed by incorporating the standard dose–response curve into the rectangular hyperbola competition model to describe the effects of plant density of a model weed, Brassica napus L., and a herbicide, metsulfuron‐methyl, on crop yield and weed seed production. The model developed in this study was used to describe crop yield and weed seed production, and to estimate the herbicide dose required to restrict crop yield loss caused by weeds and weed seed production to an acceptable level. At the acceptable yield loss of 5% and the weed density of 200 B. napus plants m–2, the model recommends 0.9 g a.i. metsulfuron‐methyl ha–1 in Avalon and 2.0 g a.i. in Spark. 相似文献
97.
KIDONG EOM HYOSUNG KWAK HYEWON KANG SANGHUN PARK HAEBEOM LEE HYUNGSUB KANG JUNGKEE KWON INSHIK KIM NAMSOO KIM KICHANG LEE 《Veterinary radiology & ultrasound》2008,49(6):545-550
Virtual otoscopy enables noninvasive 3D endoluminal imaging of the middle ear through postprocessing of computed tompgraphy (CT) data. A standardized imaging approach for the middle ear was established in six normal dogs in an attempt to optimize the clinical application and student education. High‐resolution CT data were obtained. Virtual otoscopic images of the middle ear cavity and ossicles were generated using commercially available software. The views of the four different directions (the ear canal, tympanic bulla, eustachian tube, and ossicular chain) were made for virtual otoscopy. The promontory, cochlea window, tympanic bulla, septum bulla, and auditory tube were distinguished easily and clearly. One of the ossicles, the malleus, was visualized accurately. However, small structures such as the incus and stapes always could not be seen. The main advantage of virtual otoscopy is not only to provide diagnostic information but also to enhance the quality and efficiency of student education, because it contributes to an understanding of the anatomy of the middle ear. We describe the normal topographical 3Dimages of the middle ear of the dog using virtual otoscopy. 相似文献
98.
Ren DE SONG Guo M. LI Sung D. LEE Nobumi HASEGAWA Young M. SONG Young H. KIM Hyun J. JUNG Jun C. PARK 《Animal Science Journal》2008,79(2):248-254
The objective of the present study was to investigate the effects on the plasma biochemical composition and growth of piglets of placenta‐fed sows. The experimental animals were a total of 21 sows (L × LW) of third parity, and each sow was suckled by 11 ± 1 piglets. Sows fed without placenta were considered as the control (C), treatment 1 (T1) were placenta‐fed from days 1–7 after farrowing and treatment 2 (T2) were placenta‐fed from day 7 before farrowing to day 7 after farrowing. Glucose of piglets was lower (P < 0.05) in T2 than C and T1 on day 10. Total cholesterol of piglets was higher (P < 0.05) in T2 than C on day 4. Fe of piglets was higher (P < 0.05) in T2 than C on days 4, 20 and 30. Unsaturated iron‐binding capacity was lower (P < 0.05) in T2 than C on days 4 and 30. Immunoglobulin G of piglets was higher (P < 0.05) in T1 and T2 than C on days 4 and 10. Daily gain of piglets was higher (P < 0.05) in T1 than C and T2 on day 4 when daily gain was calculated. Total daily gain increased (P < 0.05) by prolongation of placenta feeding period. The results indicate that feeding placenta to sows may improve the plasma biochemical composition and growth of their piglets. 相似文献
99.
Myung-Chul KIM JaeMyung KIM WoonKi KANG Yunho JANG Yongbaek KIM 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(1):157-160
A 3-year-old neutered female poodle with a long history of dermatophytic skin disease was
presented with lethargy, anorexia and progressive weight loss. Abdominal ultrasonography
revealed markedly enlarged mesenteric lymph nodes and multiple hypoechoic foci in the
spleen. Cytology of the mesenteric lymph nodes and spleen showed granulomatous
inflammation with fungal organisms and negatively stained intracytoplasmic bacterial rods
consistent with Mycobacteria spp. Based on culture, multiplex polymerase
chain reaction and sequence analysis, the bacterium was identified as
Mycobacterium avium subspecies hominissuis. Despite treatment with
antibiotics, the dog’s condition deteriorated, and it died approximately 3 weeks after
first presentation. 相似文献