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101.
Hanqin Liu Bo Guan Jiang Xu Changchun Hou Hua Tian Hongxi Chen 《Marine biotechnology (New York, N.Y.)》2013,15(3):321-328
Yellow catfish has become one of the most important freshwater aquaculture species in China. The mono-sex male yellow catfish has important application value in aquaculture because the male grows generally faster than the sibling females under the same conditions. This study has screened YY super-male and YY physiological female yellow catfish by sex reversal, gynogenesis, and progeny testing, which can help to achieve the large-scale production of YY super-male and XY all-male. From 2008 to 2010, about 123,000 YY super-male were produced, and about 81 million XY all-male fry were produced with 100 % male rate by random sampling. Therefore, these results indicate that YY super-male and YY physiological female yellow catfish can be viable and fertile. We conclude that the mono-sex breeding technique by YY super-male yellow catfish is stable and reliable, which has great potential for application in yellow catfish aquaculture. 相似文献
102.
在离体大鼠小脑脑片上观察了组胺对小脑皮层第Ⅹ小叶浦肯野细胞的作用。组胺(3~100μmol/L)主要引起浦肯野细胞的兴奋反应(944%,51/54),在少数细胞上也观察到组胺所引起的放电抑制现象(56%,3/54)。用低Ca2+/高Mg2+人工脑脊液灌流脑片,不能取消浦肯野细胞对组胺的兴奋反应(n=4)。H2受体对抗剂ranitidine(01~5μmol/L)能够阻断浦肯野细胞对组胺的兴奋反应(n=20),而H1受体对抗剂triprolidine(05~5μmol/L)不能够(n=9)或仅轻微地(n=4)阻断浦肯野细胞对组胺的兴奋反应。这些结果提示,组胺可能主要通过H2受体的介导对浦肯野细胞起兴奋性调节作用,下丘脑小脑组胺能神经通路可能参与了小脑的某些躯体的和非躯体的功能调节。 相似文献
103.
Comparative proteomics analysis of silkworm hemolymph during the stages of metamorphosis via liquid chromatography and mass spectrometry 下载免费PDF全文
Yong Hou Yan Zhang Jing Gong Sha Tian Jianwei Li Zhaoming Dong Chao Guo Li Peng Ping Zhao Qingyou Xia 《Proteomics》2016,16(9):1421-1431
The silkworm is a lepidopteran insect that has an open circulatory system with hemolymph consisting of blood and lymph fluid. Hemolymph is not only considered as a depository of nutrients and energy, but it also plays a key role in substance transportation, immunity response, and proteolysis. In this study, we used LC‐MS/MS to analyze the hemolymph proteins of four developmental stages during metamorphosis. A total of 728 proteins were identified from the hemolymph of the second day of wandering stage, first day of pupation, ninth day of pupation, and first day as an adult moth. GO annotations and categories showed that silkworm hemolymph proteins were enriched in carbohydrate metabolism, proteolysis, protein binding, and antibacterial humoral response. The levels of nutrient, immunity‐related, and structural proteins changed significantly during development and metamorphosis. Some, such as cuticle, odorant‐binding, and chemosensory proteins, showed stage‐specific expression in the hemolymph. In addition, the expression of several antimicrobial peptides exhibited their highest level of abundance in the hemolymph of the early pupal stage. These findings provide a comprehensive proteomic insight of the silkworm hemolymph and suggest additional molecular targets for studying insect metamorphosis. 相似文献
104.
Li W Tian H Li L Li S Yue W Chen Z Qi L Hu W Zhu Y Hao B Gao C Si L Gao F 《生物化学与生物物理学报(英文版)》2012,44(7):577-583
Lung cancer is the leading cause of cancer-related mortality all over the world. In recent years, pulmonary adenocarcinoma has surpassed squamous cell carcinoma in frequency and is the predominant form of lung cancer in many countries. Epidemiological investigations have shown an inverse relationship between garlic (Allium sativum) consumption and death rate from many cancers. Diallyl trisulfide (DATS) is one of the garlic-derived compounds (also known as: organosulfer compounds, OSC). DATS can induce apoptosis and inhibit the growth of many cancer cell lines. Our study demonstrated that the apoptotic incidents induced by DATS were a mitochondria-dependent caspase cascade through a significant decrease of the anti-apoptotic Bcl-2 that resulted in up-regulation of the ratio of Bax/Bcl-2 and the activity of caspase-3, -8, and -9. Eventually, DATS induced the apoptosis and inhibited the proliferation in a concentration- and time-dependent manner. Furthermore, by establishing an animal model of female BALB/c nude mice with A549 xenografts, we found that oral gavage of DATS significantly retarded growth of A549 xenografts in nude mice without causing weight loss or any other side effects compared with the control group. All the evidence both in vitro and in vivo suggested that DATS could be an ideal anti-cancer drug. 相似文献
105.
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107.
对党参细胞染色体进行了核型分析。研究表明,党参染色体数为2 n=16。染色体的核型为2n=12m 4 sm=16。第1、2、3、4、5、8对是中间着丝粒染色体(m);第6对和第7对染色体属于近中着丝点染色体,未观察到有携带随体的染色体存在。 相似文献
108.
CD40 signaling plays a critical role in the survival rate of gastric cancer patients. Tumour samples were collected from 73 patients with who were diagnosed as gastric cancer in general surgery department in the 1st affiliated hospital of Suzhou University between September 2002 and July 2003. All patients had not received radiotherapy and chemotherapy before operation. These patients include 46 male and 27 female. Here we show that CD40 is constitutively expressed in the human gastric carcinoma tissues, and CD40 protein and mRNA positive expression in gastric cancer tissues closely correlated with lymph node metastasis and tumour TNM stage. CD40 positive expression in gastric cancer patients with lymph node metastasis was markedly higher than that in gastric cancer patients without lymph node metastasis. CD40 positive expression in stage III-IV gastric cancer patients was markedly higher than that in stage I-II gastric cancer patients. Moreover, CD40 expression closely correlated with prognosis of gastric cancer patients. Therefore, CD40 was taken as grouping variable, and lymph node metastasis and clinical staging were taken as stratification variables, respectively, further analysis showed that prognosis in gastric cancer patients with lymph node metastasis and CD40 positive expression was markedly worse than that in gastric cancer patients without lymph node metastasis and CD40 negative expression (P = 0.0076). These results suggest that CD40 signaling plays a critical role in the survival of gastric cancer patients. 相似文献
109.
目的:构建干扰载体pSilencer 3.1-spl,并初步研究其对Spl基因的干扰作用.方法:根据Spl cDNA编码序列,设计并合成针对Spl基因的特异性RNA干扰片段,并将其克隆入pSilencer 3.1-Hl neo干扰载体中,构建Spl基因小干扰RNA(siRNA)真核表达载体pSilencer 3.1-Spl;分别将阴性对照载体pSilencer 3.1与重组载体pSilencer 3.1-Spl经脂质体LipofectAMINE2000介导转染HeLa细胞,采用RT-PCR、Western blot方法分别检测Spl基因的转录与表达水平.结果:构建了Spl基因siRNA真核表达载体pSilencer 3.1-Spl,经酶切、测序鉴定证实克隆正确,并在mRNA水平和蛋白水平证实了载体的干扰效果.结论:特异性siRNA能明显抑制Spl基因在HeLa细胞中的表达,为进一步研究Spl的生物学功能和作用机制奠定了实验基础. 相似文献
110.
濒危植物鹅掌楸(Liriodendron chinense)目前仅零散分布于我国亚热带及越南北部地区, 残存居群生境片断化较为严重。研究濒危植物片断化居群的遗传多样性及小尺度空间遗传结构(spatial genetic structure)有助于了解物种的生态进化过程以及制定相关的保育策略。本研究采用13对微卫星引物, 对鹅掌楸的1个片断化居群进行了遗传多样性及空间遗传结构的研究, 旨在揭示生境片断化条件下鹅掌楸的遗传多样性及基因流状况。研究结果表明: 鹅掌楸烂木山居群内不同生境斑块及不同年龄阶段植株的遗传多样性水平差异不显著(P>0.05), 居群内存在寨内和山林2个遗传分化明显的亚居群。烂木山居群个体在200 m以内呈现显著的空间遗传结构, 而2个亚居群内的个体仅在20 m的距离范围内存在微弱或不显著的空间遗传结构。鹅掌楸的空间遗传结构强度较低(Sp = 0.0090), 且寨内亚居群的空间遗传结构强度(Sp = 0.0067)要高于山林亚居群(Sp = 0.0053)。鹅掌楸以异交为主, 种子较轻且具翅, 借助风力传播, 在一定程度上降低了空间遗传结构的强度。此外, 居群内个体密度及生境特征也对鹅掌楸的空间遗传结构产生了一定影响。该居群出现显著的杂合子缺失, 近交系数(FIS)为0.099 (P < 0.01), 表明生境片断化的遗传效应正逐渐显现。因此, 对鹅掌楸的就地保护应注意维护与强化生境的连续性, 促进基因交流。迁地保护时, 取样距离应不小于20 m, 以涵盖足够多的遗传变异。 相似文献