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171.
栉孔扇贝人工雌核发育的细胞学观察 总被引:5,自引:1,他引:5
运用荧光显微镜观察了栉孔扇贝正常卵子与雌核发育卵子在受精和成熟分裂过程中的核相变化。结果表明,尽管紫外线照射没有影响受精卵的成熟分裂以及雌性、雄性原核的形成,但使雌核卵的发育速度出现明显的滞缓。在第1次卵裂中期,雌核发育卵子中的雄性原核没有像雌性原核那样形成染色体,而是浓缩为一染色质小体(DCB),游离在细胞质中,不参与核分裂。胞质分裂结束时,DCB位于2个卵裂球之一的细胞质内或在赤道板处被分割成两部分。实验结果首次提供了栉孔扇贝雌核发育的细胞学证据。 相似文献
172.
173.
J.D. Foster S. Sample R. Kohler K. Watson P. Muir L.A. Trepanier 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2014,28(3):905-911
Background
Immune‐mediated polyarthopathy (IMPA) is common in dogs, and is monitored by serial arthrocenteses.Hypothesis/Objectives
Plasma C‐reactive protein (CRP), interleukin‐6 (IL‐6), and CXCL8 (interleukin‐8) would serve as noninvasive markers of joint inflammation in IMPA.Animals
Nine client‐owned dogs with idiopathic IMPA; 6 healthy controls.Methods
Prospective study. Plasma CRP, IL‐6, and CXCL8 were measured by ELISA at baseline, 2, and 4 weeks during treatment with prednisone at 50 mg/m2/day. Arthrocenteses, the canine brief pain inventory (CBPI), and accelerometry collars were used to assess joint inflammation, lameness, and mobility at all 3 time points.Results
C‐reactive protein concentrations were higher in IMPA dogs (median 91.1 μg/mL, range 76.7–195.0) compared with controls (median <6.3 μg/mL, <6.3–13.7; P = .0035), and were significantly lower at week 2 (10.6 μg/mL, <6.3–48.8) and week 4 (<6.3 μg/mL, <6.3–24.4; P < .001).C‐reactive protein was correlated with median CBPI scores (r = 0.68; P = .0004), joint cellularity (r = 0.49, P = .011), and mobility by accelerometry (r = −0.42, P = .048). Plasma IL‐6 concentrations were also higher in IMPA dogs (median 45.9 pg/mL), compared with controls (median <15.7 pg/mL; P = .0008). IL‐6 was lower in IMPA dogs by week 4 (<15.7 pg/mL; P = .0099), and was modestly correlated with CBPI scores (r = 0.47, P = .023). CXCL8 did not differ significantly between IMPA and healthy dogs.Conclusions
Plasma CRP and IL‐6 might be useful surrogate markers of synovial inflammation and disease activity in dogs with IMPA. 相似文献174.
175.
将40羽220日龄ISA蛋鸡分为5组,于产蛋后0、2、4.5、8、16h断头处死,采集蛋壳腺组织,运用Real-time PCR和Western-blot方法检测产蛋循环过程中瞬时性受体单位香草精受体6(Transient receptor potential vanilloid receptor 6,TRPV6)、钙结合蛋白(calbindin D28K,CaBP-D28K)、质膜钙离子ATP酶1b(plasma membrane Ca2+-ATPase 1b,PMCA 1b)mRNA和蛋白浓度的动态变化。结果显示,卵子未进入蛋壳腺前(产蛋后0~4.5h),蛋壳腺内TRPV6、CaBP-D28K和PMCA 1bmRNA表达水平较低,随后表达量逐渐升高,在蛋壳钙化过程中达到最大值(产蛋后16h),与0h相比,TRPV6和CaBP-D28KmRNA表达差异均极显著(P〈0.01);另外,产蛋循环过程中,TRPV6、CaBP-D28K和PMCA 1b蛋白浓度变化与mRNA变化一致,产蛋后16h到达最大值,其中CaBP-D28K蛋白浓度与0h相比,差异显著(P〈0.05)。结果表明,产蛋循环可调控蛋壳腺内TRPV6、CaBP-D28K和PMCA 1b的表达,并提示钙离子跨细胞转运途径在钙离子进入蛋壳腺形成蛋壳过程中发挥重要作用。 相似文献
176.
Optimal conditions of 6‐dimethylaminopurine (6‐DMAP) for triploidy induction in the blacklip abalone Haliotis rubra (Leach, 1814) were investigated, targeting inhibition of second polar body (PB2) formation. Two experiments were conducted at a water temperature of 17.5–18.5°C where factorial combination of (1) four dosages (DSs) of 100, 150, 200 and 250 μM 6‐DMAP, four starting times (STs) of 15, 20, 25 and 30 min post fertilization, and two treatment durations (TDs) of 20 and 30 min and (2) three DSs of 50, 100 and 150 μM 6‐DMAP, three STs of 15, 20 and 25 min post fertilization, and three TDs of 10, 20 and 30 min, were applied respectively. Day 3 larvae were sampled for triploidy and survival. Percent triploidy was verified using flow cytometry (FCM). Results show that optimal inductions that combine both high rates of triploidy and reasonable survival were those treatments commenced 15 or 20 min post fertilization and continued for 20 or 30 min, using 100 μM 6‐DMAP. These conditions induced rates of triploidy and relative survival of 80.5–93.3% and 36.5–40.2%, respectively, in the first experiment, and corresponding rates were 79.1–93.6% and 20.7–43.0% in the second experiment. High percent triploidy were also obtained in a number of treatments using 150 μM 6‐DMAP, but with overall survival rates generally lower than those using 100 μM 6‐DMAP. 相似文献
177.
KANG Jing-jing ZHAO De-ming TENG Ke-dao JIAO Xi-lan WANG Ping-li SUN Zhe NI Pei-pei WANG Zhi-feng ZHANG Rui YANG Yu-rong LIANG Hong-de 《农业科学学报》2014,13(4):858-869
Ulcerative colitis (UC) is a lifelong illness with profound emotional and social impacts, and could cause serious damage to large intestine, especially in colon. However, the pathogenesis of UC remained unclear. The present study attempts to find out the role of matrix metalloproteinases-7 (MMP-7) and lysozyme in the pathogenesis of UC through a mice model induced by dextran sulfate sodium (DSS). The UC model was evaluated both by disease activity index (DAI) and the intestinal histopathology. The results show that there is a high correlation between the DAI score and the pathological changes of colon. Interleukin-6 (IL-6) serum levels and large intestinal fluids levels in UC mice are always higher than that of the control groups, which might be associated with the degree of the inflammation damage in the colon. The change tendency of the MMP-7 mRNA and protein expressions are both up-regulated firstly and then down-regulated from 1 to 5 d in the colon, but only the MMP-7 protein is up-regulated at 7 d again. The up-regulated MMP-7 levels in the early stage of UC may play a protective role through the activated defensins, while the down-regulated levels in the mid-later stage of UC may be connected with the severe lesions in the colon. However, the up-regulated MMP-7 levels in the later stage of UC in the colon may also contribute to the tissue repair or be served as a marker to CRC (colorectal cancer). The distribution of lysozyme protein indicates that there may be Paneth-like cells in the colon. Both the changes of MMP-7 and lysozyme in the small intestine may play a protective role for the safe environment of the whole gut, especially to the colon of UC. 相似文献
178.
179.
兰州百合高效再生体系的建立 总被引:4,自引:0,他引:4
以兰州百合新鲜鳞片为试材进行高效再生体系的研究。结果表明:兰州百合中层、内层鳞片比外层鳞片容易再生不定芽,更适于作为外植体。鳞片在MS+0.5 mg·L-1 6-BA+0.5 mg·L-1 NAA 的诱导培养基上再生频率最高,可达90%;不定芽在MS+0.8 mg·L-1 6-BA+0.05 mg·L-1 NAA 的增殖培养基上增殖率最高,平均每芽新增芽4.5 个;不定芽在MS+0.8 mg·L-16-BA+0.05 mg·L-1 NAA+0.5 mg·L-1 AC 的壮苗生根培养基上鳞茎的膨大倍数最高,生根数量较多,小苗长势优,移栽后成活率达98% 以上。 相似文献
180.