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31.
Myostatin (GDF-8, MSTN) is a member of trans- forming growth factors (TGF-β) superfamily, which was first described by McPherron et al. in 1997[1]. Myostatin appears to act as a negative regulator of muscle development and controls not only fibre size but also fibre number[2,3]. Mutations in the third exon of the myostatin gene have been shown to cause dou- ble muscling in cattle[4]. By knocking out the gene of myostatin in mice, they were able to show that the transgenic mice developed …  相似文献   
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Anurans often have species-specific vocalizations. To quantify and compare the characteristics of anuran calls in Gutianshan National Nature Reserve, Zhejiang Province, we recorded the advertisement calls of eight species belonging to four families (Ranidae, Microhylidae, Megophryidae and Bufonidae) from June to September 2012 using Sony ICD-FX8 IC recorders. All recordings were analyzed using the "Praat" software. Five acoustics parameters were measured, including temporal traits (call duration, number of notes or pulse number/call) and spectral traits (fundamental frequency, the first three formants and dominant frequency). The characteristic parameters of Microhyla ornate and Fejervarya limnocharis calls were different as were the calls of some populations of the same species recorded in different regions. The advertisement calls of the eight species were specific. Our study has provided a useful reference for identifying the calls of some common Chinese anurans.  相似文献   
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微藻是可广泛用于健康食品及水产养殖的饵料,同时,微藻细胞内积累的油脂可作为可再生生物燃料,因此微藻的生长和代谢受到广泛关注。温度和pH对微藻的生物量积累有很大影响,考察不同温度和pH条件下微藻细胞的生长有助于寻找最佳的条件进行微藻的培养。自絮凝小球藻JSC-7(Chlorella vulgaris JSC-7)可实现自沉降采收,有利于降低微藻生产成本,优化其生长条件对更好地利用该微藻具有重要意义。考察了温度(22∽40℃)及pH(6.0∽10.0)对其细胞生长、叶绿素含量和油脂产量的影响。在所选取的温度及pH范围内,JSC-7细胞均可生长,显示该藻种可以适应广泛的温度和pH条件。适合细胞生长的温度依次为31℃〉28℃〉35℃〉25℃,pH依次为7.0〉8.0〉6.0。pH 8.0时生物量和油脂的积累量最多,说明该藻株在弱碱条件下更适合生长和产油。当温度为31℃、pH为7.0时,可获得最高的生长量(OD690=0.941)、叶绿素含量(19 mg/L)及油脂产量(39.07%/克干重)。  相似文献   
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Studies on the chaperone proteinα-hemoglobin stabilizing protein(AHSP)reveal that abundant AHSP in erythroid cells enhance the cells’tolerance to oxidative stress imposed by excessα-hemoglobin in pathological conditions.However,the potential intracellular modulation of AHSP expression itself in response to oxidative stress is still unknown.The present study examined the effect and molecular mechanism of STAT3,an oxidative regulator,on the expression of AHSP.AHSP expression increased in K562 cells upon cytokine IL-6-induced STAT3 activation and decreased in STAT3 knock-down K562 cells.Regulation of AHSP in oxidative circumstance was then examined inα-globin-overloaded K562 cells,and real-time PCR showed strengthened expression of both AHSP and STAT3.ChIP analysis showed binding of STAT3 to AHSP promoter and binding was significantly augmented with IL6 stimulation and uponα-globin overexpression.Dual luciferase reporter assays of the wildtype and mutated SB3 element,an IL-6RE site,in the AHSP promoter in K562 cells highlighted the direct regulatory effect of STAT3 on AHSP gene.Finally,direct binding of STAT3 to SB3 site of AHSP promoter was confirmed with EMSA assays.Our work reveals an adaptive AHSP regulation mediated by the redox-sensitive STAT3 signaling pathway,and provides clues to the therapeutic strategy for AHSP enhancement.  相似文献   
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鳜鱼(Sinipera chuatsi)鱼苗肠道微生态调节的研究   总被引:4,自引:0,他引:4  
对鳜鱼鱼苗肠道菌进行好氧菌和兼性厌氧菌的分析鉴定 ,发现鳜苗肠道中存在哈夫尼亚菌属和气单胞菌属 ,其中哈夫尼亚菌属量为 4 .8× 10 6cfu/ g ,气单胞菌属量为 2 .4 3× 10 5cfu/ g。哈夫尼亚菌属和气单胞菌属的拮抗实验表明哈夫尼亚菌对气单胞菌的生长有一定的抑制作用。分别用哈夫尼亚菌、气单胞菌作饵料添加剂 ,前者将鱼苗成活率由 18%提高至 33%~ 4 0 % ,后者将鱼苗成活率由 18%降至 2 %~ 4 %。  相似文献   
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Topical application of the Metarhizium anisopliae var. acridum specialist strain CQMa 102 to the locust Locusta migratoria manilensis results in changes of the concentrations of trehalose and glucose in the haemolymph. Micrographs of the locust haemolymph shows Metarhizium anisopliae can effectivly penetrate the external skeleton of locust and after 2 days infection, the hyphae body will appear in the haemolymph of infected insects. The time in decrease of trehalose concentration coincided with that in increase of trehalose-hydrolysing enzyme activity in the haemolymph of the fungus-infected insects. Overlay gel analysis indicated there was considerably more trehalose-hydrolysing activity in the haemolymph of locusts infected by fungus than in controls. A comparable isoform was identified in in vitro culture of the fungus, suggesting a fungal origin for the in vivo enzyme. Haemolymph trehalose decreased significantly during mycosis of locusts by M. anisopliae. All these results suggested that this fungus may take advantage of competing nutrient utilization against the insect by its trehalose-hydrolyzing enzyme secretion. It may provide fundamental knowledge for fungal pathogenesis.  相似文献   
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Two Oedipodinae grasshopper species Oedaleus decorus asiaticus B.-Bienko and Angaracris baraben-sis Pall. (Orthoptera: Acrididae) are important pests on the natural grasslands in Inner Mongolia and often require insecticide treatment during outbreaks[1]. They both prefer overgrazed steppes and xerophytous habi-tats, and have thus been suggested as indicator species for steppe deterioration in typical steppe zones of In-ner Mongolia[2]. The two species have a sympatric distribution and sync…  相似文献   
40.
In China, the estimated number of HIV infected cases is approaching one million. Although public education has been initiated for awareness and behavioral modification for this devastating infection, better diagnostic methods are needed to identify infected persons and manage infection. Simple and more accurate diagnostic tools have become available, particularly for early detection and to monitor treatment in those who receive anti-retroviral treatment. In this short review, we summarize some of the common and new methodologies that can be used in clinical laboratories, in the field, or in private laboratories. These range from simple antibody tests to more sophistical methods that are used to monitor disease progression and identify drug resistance. These tools can assist physicians, medical practitioners, and laboratory personnel to select suitable diagnostic tools for the diagnosis, blood screening, monitoring of disease progression, and for detection of drug resistance to anti-retroviral therapies.  相似文献   
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