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51.
重庆市爬行动物物种多样性研究及保护   总被引:6,自引:4,他引:6  
罗键  高红英  周元媛 《四川动物》2004,23(3):249-256
1996~2004年对重庆市35个县(区、市)进行野外调查采集,结合有关资料记载,重庆市共有爬行动物2目12科38属58种,其中龟鳖目4种,有鳞目蜥蜴亚目12种、蛇亚目42种(含重庆市蛇类新记录3属4种)。建议加强对该市爬行动物物种多样性及其生境的保护,合理利用爬行动物资源。  相似文献   
52.
PTSD促进大鼠中缝背核细胞色素c表达   总被引:1,自引:1,他引:1  
目的研究创伤后应激障碍(PTSD)大鼠中缝背核神经元细胞色素C(Cyt-c)的表达变化。方法应用无连续单一刺激(SPS)方法建立PTSD大鼠模型,随机分为SPS刺激后1d、4d、7d和对照组,应用酶组织化学法和RT-PCR方法观察中缝背核神经元Cyt-c的表达变化。结果光镜酶细胞化学法和RT-PCR法显示中缝背核神经元Cyt-c染色阳性细胞于SPS刺激后1d明显高于对照组,4d逐渐增高,并于7d达到高峰。电镜下显示Cyt-c阳性反应产物主要分布在中缝背核神经元线粒体膜,SPS刺激后可见Cyt-c释放到胞浆中。结论 SPS刺激引起Cyt-c在PTSD大鼠中缝背核神经元呈过表达。  相似文献   
53.
Negative control of p53 by Sir2alpha promotes cell survival under stress.   总被引:50,自引:0,他引:50  
J Luo  A Y Nikolaev  S Imai  D Chen  F Su  A Shiloh  L Guarente  W Gu 《Cell》2001,107(2):137-148
The NAD-dependent histone deacetylation of Sir2 connects cellular metabolism with gene silencing as well as aging in yeast. Here, we show that mammalian Sir2alpha physically interacts with p53 and attenuates p53-mediated functions. Nicotinamide (Vitamin B3) inhibits an NAD-dependent p53 deacetylation induced by Sir2alpha, and also enhances the p53 acetylation levels in vivo. Furthermore, Sir2alpha represses p53-dependent apoptosis in response to DNA damage and oxidative stress, whereas expression of a Sir2alpha point mutant increases the sensitivity of cells in the stress response. Thus, our findings implicate a p53 regulatory pathway mediated by mammalian Sir2alpha. These results have significant implications regarding an important role for Sir2alpha in modulating the sensitivity of cells in p53-dependent apoptotic response and the possible effect in cancer therapy.  相似文献   
54.
L Zhang  J Luo  M Hao  L Zhang  Z Yuan  Z Yan  Y Liu  B Zhang  B Liu  C Liu  H Zhang  Y Zheng  D Liu 《BMC genetics》2012,13(1):69-8
ABSTRACT: BACKGROUND: A synthetic doubled-haploid hexaploid wheat population, SynDH1, derived from the spontaneous chromosome doubling of triploid F1 hybrid plants obtained from the cross of hybrids Triticum turgidum ssp. durum line Langdon (LDN) and ssp. turgidum line AS313, with Aegilops tauschii ssp. tauschii accession AS60, was previously constructed. SynDH1 is a tetraploidization-hexaploid doubled haploid (DH) population because it contains recombinant A and B chromosomes from two different T. turgidum genotypes, while all the D chromosomes from Ae. tauschii are homogenous across the whole population. This paper reports the construction of a genetic map using this population. RESULTS: Of the 606 markers used to assemble the genetic map, 588 (97%) were assigned to linkage groups. These included 513 Diversity Arrays Technology (DArT) markers, 72 simple sequence repeat (SSR), one insertion site-based polymorphism (ISBP), and two high-molecular-weight glutenin subunit (HMW-GS) markers. These markers were assigned to the 14 chromosomes, covering 2048.79 cM, with a mean distance of 3.48 cM between adjacent markers. This map showed good coverage of the A and B genome chromosomes, apart from 3A, 5A, 6A, and 4B. Compared with previously reported maps, most shared markers showed highly consistent orders. This map was successfully used to identify five quantitative trait loci (QTL), including two for spikelet number on chromosomes 7A and 5B, two for spike length on 7A and 3B, and one for 1000-grain weight on 4B. However, differences in crossability QTL between the two T. turgidum parents may explain the segregation distortion regions on chromosomes 1A, 3B, and 6B. CONCLUSIONS: A genetic map of T. turgidum including 588 markers was constructed using a synthetic doubled haploid (SynDH) hexaploid wheat population. Five QTLs for three agronomic traits were identified from this population. However, more markers are needed to increase the density and resolution of this map in the future study.  相似文献   
55.
罗放  俞易  陈铭哲  杨以清  魏垠 《生物工程学报》2018,34(12):1895-1905
外源基因的表达及其对细菌种群的影响对于群体感应系统和合成生物学产业的研究具有重要意义。然而,人们对于表达外源蛋白的细菌本身的行为模式仍然知之甚少。为了研究菌落生长和外源基因表达的过程究竟受到哪些因素的影响,文中测量了受Lux类受体调控的外源基因在N-酰基高丝氨酸内酯 (N-acyl homoserine lactone,N-AHL) 信号分子诱导下的表达,并模拟了其对细菌种群动态的影响。文中建立了一个假设性的数学模型,对信号分子诱导表达下细菌种群生长受影响的现象进行了分析。先前的研究通常将细菌种群生长受群体感应系统影响的现象归咎于合成群体感应信号分子的消耗与N-AHL信号分子的毒性,文中提供了对于这种生存压力的另一种可能的解释。  相似文献   
56.
Biology, fisheries, and conservation of sturgeons and paddlefish in China   总被引:26,自引:0,他引:26  
This paper reviews five of the eight species of acipenseriforms that occur in China, chiefly those of the Amur and Yangtze rivers. Kaluga Huso dauricus and Amur sturgeon Acipenser schrenckii are endemic to the Amur River. Both species still support fisheries, but stocks are declining due to overfishing. Acipenseriformes of the Yangtze River are primarily threatened by hydroelectric dams that block free passage to spawning and feeding areas. The Chinese paddlefish Psephurus gladius now is rare in the Yangtze River system, and its spawning activities were severely limited by completion of the Gezhouba Dam in 1981. Since 1988, only 3–10 adult paddlefishes per year have been found below the dam. Limited spawning still exists above the dam, but when the new Three Gorges Dam is complete, it will further threaten the paddlefish. Artificial propagation appears to be the only hope for preventing extinction of P. gladius, but it has yet to be successfully bred in captivity. Dabry's sturgeon A. dabryanus is a small, exclusively freshwater sturgeon found only in the Yangtze River system. It is concentrated today in reaches of the main stream above Gezhouba Dam. The fishery has been closed since 1983, but populations continue to decline. Acipenser dabryanus has been cultured since the 1970s, and holds promise for commercial aquaculture; availability of aquacultural methods offers hope for enhancing natural populations. The Chinese sturgeon A. sinensis occurs in the Yangtze and Pearl rivers and seas of east Asia. There is still disagreement about the taxonomy of the Pearl and Yangtze River populations. The Yangtze River population is anadromous. Adults begin spawning at about age 14 years (males) and 21 years (females), and adults spend over 15 months in the river for reproduction. Spawning sites of A. sinensis were found every year since 1982 below the Gezhouba Dam, but it seems that insufficient suitable ground is available for spawning. Since 1983, commercial fishing has been prohibited but more measures need to be taken such as establishing protected areas and characterizing critical spawning, summering and wintering habitats.  相似文献   
57.
鸭稻共作生态农业模式的功能与效益分析   总被引:41,自引:1,他引:41  
对鸭稻共作生态农业模式的结构、功能和效益进行了综合分析。结果表明,鸭子和水稻可以较好地全天候地同生共长在稻田生态系统中,平均每公顷大约300-375只鸭子。利用鸭子的野性和杂食性在一定程度上可防除病、虫、草害,提高土壤肥力,因而可代替人耕耙田、施肥、施药等,避免了农药和化肥的大量投入;鸭群的活动可刺激和促进水稻的生长发育。利用这种模式可以生产出有机食品或绿色稻米,其经济效益比常规稻作高。鸭稻共作系统的每公顷净收入比常规稻作系统要高出808.5元。若按绿色食品价格高出同类商品市场价格的20%计算,则鸭稻共作系统每公顷比常规稻作系统大约多增加2000元左右的收入。这种模式的推广应用可产生良好的生态-经济-社会效益。  相似文献   
58.
We looked for variations that could be associated with chicken egg number at 300 days of age (EN300) in seven genes of the hypothalamic-pituitary-gonadal axis, including gonadotrophin-releasing hormone-I (GnRH-I), GnRH receptor (GnRHR), neuropeptide Y (NPY), dopamine D2 receptor (DRD2), vasoactive intestinal polypeptide (VIP), VIP receptor-1 (VIPR-1), prolactin (PRL), and the QTL region between 87 and 105 cM of the Z chromosome. Ten mutations in the seven genes were chosen to do marker-trait association analyses in a population comprising 1310 chickens, which were obtained from a company located in Guangdong Province of China. The C1704887T of VIPR-1 was found to have a highly significant association with EN300. The T5841629C of DRD2 and the C1715301T of VIPR-1 were significantly associated with EN300. A highly significant association was also found between the C1704887T-C1715301T haplotypes of VIPR-1 and EN300. H1H3 had the highest EN300. Four PCR-RFLP variations in the candidate QTL region were selected to investigate their genetic effects on EN300. The haplotypes of T32742468C-G32742603A in this region showed a highly significant association with EN300. Bioinformatics analyses showed that both T32742468C and G32742603A were located in intron 1 of the SH3-domain GRB2-like 2 (SH3GL2) gene. We conclude that five SNPs, including C1704887T and C1715301T of VIPR-1, T5841629C of DRD2, and T32742468C and G32742603A of SH3GL2, would be useful as markers for breeding to increase chicken EN300.  相似文献   
59.
Introduction: Abnormal biomechanics plays a role in intervertebral disc degeneration. Adipose-derived stromal cells (ADSCs) have been implicated in disc integrity; however, their role in the setting of mechanical stimuli upon the disc''s nucleus pulposus (NP) remains unknown. As such, the present study aimed to evaluate the influence of ADSCs upon NP cells in compressive load culture.Methods: Human NP cells were cultured in compressive load at 3.0MPa for 48 hours with or without ADSCs co-culture (the ratio was 50:50). We used flow cytometry, live/dead staining and scanning electron microscopy (SEM) to evaluate cell death, and determined the expression of specific apoptotic pathways by characterizing the expression of activated caspases-3, -8 and -9. We further used real-time (RT-) PCR and immunostaining to determine the expression of the extracellular matrix (ECM), mediators of matrix degradation (e.g. MMPs, TIMPs and ADAMTSs), pro-inflammatory factors and NP cell phenotype markers.Results: ADSCs inhibited human NP cell apoptosis via suppression of activated caspase-9 and caspase-3. Furthermore, ADSCs protected NP cells from the degradative effects of compressive load by significantly up-regulating the expression of ECM genes (SOX9, COL2A1 and ACAN), tissue inhibitors of metalloproteinases (TIMPs) genes (TIMP-1 and TIMP-2) and cytokeratin 8 (CK8) protein expression. Alternatively, ADSCs showed protective effect by inhibiting compressive load mediated increase of matrix metalloproteinases (MMPs; MMP-3 and MMP-13), disintegrin and metalloproteinase with thrombospondin motifs (ADAMTSs; ADAMTS-1 and 5), and pro-inflammatory factors (IL-1beta, IL-6, TGF-beta1 and TNF-alpha).Conclusions: Our study is the first in vitro study assessing the impact of ADSCs on NP cells in an un-physiological mechanical stimulation culture environment. Our study noted that ADSCs protect compressive load induced NP cell death and degradation by inhibition of activated caspase-9 and -3 activity; regulating ECM and modulator genes, suppressing pro-inflammatory factors and preserving CK8. Consequently, the protective impact of ADSCs found in this study provides an essential understanding and expands our knowledge as to the utility of ADSCs therapy for intervertebral disc regeneration.  相似文献   
60.
睫状神经营养因子对大鼠去神经骨骼肌的营养作用   总被引:6,自引:0,他引:6  
目的:了解睫状神经营养因子(CNTF)对去神经引起的肌肉萎缩的治疗作用。方法:离断SD大鼠一侧坐骨神经,连续给予CNTF20d,观察肌肉湿重、蛋白含量、肌纤维横截面积、收缩性能和残肢程度。结果:①给予0.2mg/kg的CNTF,可使损务侧肌纤维横截面积增加35%,肌肉湿重增加38%,胫前肌总蛋白含量增加24%,腓长肌强直收缩强度提高40%,显著改善肢残程度;②0.2mg/kg的CNTF作用明显强于0.05mg/kg的CNTF;③此目鱼肌(慢肌)比伸趾长肌(快肌)对CNTF更敏感。结论:CNTF能显著改善成年大鼠坐骨神经离断后骨骼肌的萎缩和功能丧失,该效应的强弱与用药剂量和肌肉类型有关。  相似文献   
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