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1.
观赏水草是水族箱的重要组成部分,其消费日渐成熟。淘宝在售的观赏水草有淡水观赏水草17科22属96种(含品种),海水观赏水草10科11属13种。其中,淡水观赏水草有20种只具有观赏用途,占总种数的20.83%;76种兼具稳定水质和观赏用途,占总种数的79.17%。海水观赏水草有3种只具有观赏用途,2种兼具观赏和净化水质的用途,8种具有观赏、净化水质和饲用3种用途。淡水种类绝大部分都是外来种,仅13种在中国有分布,仅占总种数的13.54%;海水种类由于海水传播的特殊性,均为全球广布种或东太平洋种类。  相似文献   
2.
旨在探究宿主蛋白程序性细胞死亡因子10(programmed cell death factor 10,PDCD10)通过抑制Ⅰ型干扰素表达进而促进口蹄疫病毒(foot-and-mouth disease virus,FMDV)的复制。首先,本研究验证了过表达和沉默PDCD10对FMDV复制的影响,接着利用双荧光素酶报告系统探究PDCD10对Ⅰ型干扰素信号通路活化的影响,最后,利用实时荧光定量PCR探究PDCD10对Ⅰ型干扰素通路下游刺激基因(IFN-stimulated genes,ISGs)转录的影响。结果表明,过表达PDCD10显著促进FMDV的复制,沉默PDCD10显著抑制FMDV的复制。与对照相比,过表达PDCD10后感染仙台病毒(Sendai virus,SeV)的细胞培养液上清液显著促进FMDV复制,进一步,PDCD10显著抑制SeV诱导的IFN-β启动子以及NF-κB的激活且呈剂量依赖性,并且PDCD10负调控Ⅰ型干扰素通路信号分子转录,最后还发现PDCD10负调控Ⅰ型干扰素下游ISGs转录。本研究结果为深入探究PDCD10在抗病毒天然免疫中的作用积累了资料。  相似文献   
3.
AIM: To investigate the ultrastructural changes of islet microvascular endothelial cells in STZ-induced type 1 diabetic mice. METHODS: BALB/c mice were randomly divided into diabetic group and control group. The expression of insulin and platelet-endothelial cell adhesion molecule-1 (CD31) in islet microvessels was detected by immunohistochemical staining. The ultrastructural changes of islet β cells and islet microvessels were observed under transmission electron microscope. RESULTS: Compared with control group, the number of islet β cells, ratio of β cells/α cells, average number of secretory granules in β cells and insulin expression area per islet in diabetic group were significantly decreased (P<0.01). Besides, diabetic group had fewer microvessels with lower expression of CD31 (P<0.01). Mitochondria in islet microvascular endothelial cells and pericytes in diabetic group were swelling. The basement membrane of islet microvessels became thicker in diabetic group (P<0.01). CONCLUSION: Islet microvascular endothelial cells were impaired in type 1 diabetic mice.  相似文献   
4.
AIM: To explore the effects of hydrogen sulfide (H2S) on the myocardial fibrosis in a rat model of diabetes and its mechanism.METHODS: Single intraperitoneal injection of streptozotocin (STZ) was utilized to establish a rat model of diabetes. Sodium hydrosulfide was used as an exogenous donor of hydrogen sulfide. Male SD rats were randomly divided into control group, STZ group, STZ+H2S group and H2S group. Eight weeks later, HE and VG staining methods were used to observe the collagen distribution and collagen volume fraction was measured by image analysis. The expression levels of type I collagen, PPARγ and NF-κB in the cardiac tissues were determined by Western blotting.RESULTS: Compared with control group, collagen distribution and the expression levels of type I collagen and NF-κB in the cardiac tissues were markedly increased (P<0.05), while PPARγ was significantly decreased in STZ group (P<0.05), but these indexes were reversed significantly in STZ+H2S group (P<0.05). The expression levels of type I collagen, PPARγ and NF-κB had no significant difference between H2S group and control group.CONCLUSION: Hydrogen sulfide attenuates cardiac fibrosis in diabetic rats, and its mechanism may be related to PPARγ-NF-κB signaling pathway.  相似文献   
5.
缓释肥类型与运筹对不同穗型水稻产量的影响   总被引:24,自引:0,他引:24  
以大穗型品种甬优2640和多穗型品种南粳9108为材料,270 kg hm–2纯氮条件下,选用树脂包衣(PCU)、硫包衣(SCU)和脲甲醛(UF)3种缓控释肥类型,设置了缓控释肥与尿素均基施、缓控释肥基施后分蘖期施尿素2种施肥方式,以常规尿素定量分施为对照(CK)。结果表明,缓控释肥的应用对甬优2640无增产效应。主要因为甬优2640穗大粒多,群体颖花量大。与CK比,相对集中在前中期的肥效难以满足植株全生育期生长,中后期叶面积指数下降快,氮素积累少,光合势弱,物质生产量不足,不能实现群体大库容的有效充实。而对南粳9108,脲甲醛基施+尿素分蘖期施处理比CK增产5.2%~5.9%,树脂包衣基施+尿素分蘖期施和脲甲醛+尿素均基施处理与CK平产的同时可减少施肥2~3次。2种运筹方式中,以缓控释肥基施后分蘖期施用尿素处理能有效增加植株茎蘖数,提高成穗率和最终穗数,扩大叶面积指数,增强光合势,增加干物质和氮素的积累,获得高产。3种肥料类型中,产量呈现UFPCUSCU。脲甲醛基施+分蘖期施尿素处理之所以能使南粳9108获得比CK更高的产量,是因为UF的肥效在中后期依然能相对稳定释放,配合尿素的分蘖期施用,既保证了前期分蘖的发生,又能保证高峰苗后稳定的茎蘖数和群体叶面积指数,植株在拔节后的光合势和物质积累量大,氮肥利用率高,增产显著。由此可见,针对不同穗型和产量特性的水稻品种,优选缓控释肥类型基施的同时,分蘖期配合速效肥料的施用,可获得既省工又增产的效果。  相似文献   
6.
Type II innate lymphoid cells (ILC2s) are widely distributed in the blood, intestines, trachea, lung, spleen, liver, animal fat and skin, and involved in the innate immune responses. ILC2s have attracted much attention for its important roles in the conversion of white adipose to beige adipose. Studies have shown that ILC2s are essential for the proliferation and differentiation of adipocyte precursor cells, and they also play a vital role in anti-parasitic infection and allergic inflammation. This review discusses the discovery, differentiation, development, distribution and function of ILC2s, and their relationships with the browning of white adipose tissue for providing valuable references on understanding the pathogenesis, prevention and treatment of obesity and fat metabolism disorders.  相似文献   
7.
8.
AIM To investigate whether microRNA-9-5p (miR-9-5p) mediates sympathetic overactivity by targeting KCNN3 (potassium intermediate/small conductance calcium-activated channel, subfamily N, member 3) gene,which encoded small-conductance calcium-activated potassium channel 3 (SK3) protein, in paraventricular nucleus (PVN) of rats with type 2 diabetes mellitus (T2D). METHODS A rat model of T2D was established by high-fat diet combined with intraperitoneal injection of 30 mg/kg streptozotocin. The levels of miR-9-5p and KCNN3 mRNA in PVN were detected by real-time PCR. The relationship between KCNN3 and miR-9-5p was predicted by TargetScan. Recombinant adeno-associated virus (rAAV)-miR-9-5p or KCNN3 were bilaterally microinjected into the PVN to observe the changes in plasma glucose levels and sympathetic drive indicators. The number of FosB and SK3 positive cells was measured by immunofluorescence staining. The protein expression of SK3 was determined by Western blot. The relationship between KCNN3 and miR-9-5p were confirmed by cell transfection and dual-luciferase reporter assay. RESULTS Compared with the rats in diabetes control (DC) group, the blood glucose, sympathetic drive indexes and the level of miR-9-5p in PVN were significantly increased, while the SK3 expression in PVN was obviously reduced in the diabetes mellitus (DM) rats. After microinjecion of rAAV-miR-9-5p in PVN, the sympathetic drive indexes, blood glucose, and the number of FosB-positive cells were increased significantly, but the SK3 protein expression was significantly reduced (P<0.05). However, up-regulation of KCNN3 in PVN had the opposite effect. These responses were obviously enhanced in DM rats compared with DC rats. The results of cell transfection and dual-luciferase reporter assay demonstrated that miR-9-5p bound to the 3’-UTR of KCNN3 and inhibit its expression. CONCLUSION miR-9-5p was up-regulated in PVN of the rats with T2D, and it may mediate sympathoexcitation by targeting KCNN3.  相似文献   
9.
大熊猫野化培训圈森林植物群落多样性研究   总被引:7,自引:0,他引:7  
本文应用植物群落学理论分析了卧龙大熊猫野化培训圈的植物种类组成、区系地理成分、优势树种以及生活型谱等特征。结果表明:大熊猫野化培训圈主要为野核桃、红肤杨、华西枫杨、连香树、扇叶槭、五裂槭、大翅色木槭、长序稠李、槐树等树种组成的落叶阔叶林。栖息地群落中分布的常见种子植物有71种,分属39科,58属,其中裸子植物3种,双子叶植物63种,单子叶植物5种;且以槭树科、杜鹃花科、忍冬科、蔷薇科、竹亚科、虎耳草科、菊科、百合科、禾本科等科植物构成优势组分。占组成植物总数的40.8%以上。从植物地理成分分析来看,无论是科分布型,还是属分布型,大熊猫栖息地植物都以温带分布类型为主,分别占57.5%和46.55%。植物群落生活型谱中以高位茅植物占优势,达56.34%,反映出大熊猫野化培训圈的植物群落具有温带落叶阔叶林特点,这与卧龙大熊猫栖息地的植物群落的生态特征相似。根据植物群落分类原则,将野化培训圈的植物群落共划分为连香树-拐棍竹-黑鳞耳蕨群落、野核桃-短锥玉山竹群落、野核桃-拐棍竹-艾蒿群落和野核桃-薄叶鼠李-小鳞苔草群落等4个类型。  相似文献   
10.
中国银杏的种核类型及其特征   总被引:18,自引:0,他引:18  
银杏种内变异较大。 2 0世纪 5 0年代起 ,通过广泛调查、收集我国银杏的核用品种资源 ,对种实不同发育时期的组织结构及形态特征进行了解剖观察。主要根据种实的珠托、种核的形状、长、宽、厚及种核两侧、顶端的特征 ,将银杏种核分为长子、佛指、马铃、梅核、圆子 5种类型 ,并确定了隶属于各个类型的主要栽培品种。通过对每一类型的种核重、核形指数及种仁中干物质、直链淀粉、支链淀粉、淀粉、粗蛋白、可溶性糖、氢氰酸含量的分析 ,对种核品质作了鉴评 ,为银杏核用品种资源的利用和改良提供了依据。  相似文献   
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