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111.
罗芳丽  曾波  叶小齐  陈婷  刘巅 《生态学报》2008,28(5):1964-1964~1970
为了阐明水淹对三峡库区岸生植物秋华柳(Salix variegata Franch.)和野古草(Arundinella anomala Steud.)水下光合作用的影响,模拟三峡库区消落带水淹发生情况,考察了在不同水淹处理下秋华柳和野古草的水下光合.实验设置了对照(不进行水淹,常规供水管理)和2m深度水淹(植株置于水中,植株顶部在水面下2 m)2个不同的水淹深度和5、15、20、40 d和60 d等5个不同的水淹时间处理,采用Chlorolab-2液相氧电极(英国Hansatech公司生产)测定了在不同水淹时间和水淹深度处理下秋华柳和野古草的水下光合作用.实验结果表明: (1) 水淹60d后,秋华柳和野古草的存活率均为100%,而典型的陆生植物香樟和马唐分别在水淹40d和15d后全部死亡.(2) 在相同的水淹时间和水淹深度下,秋华柳和野古草的水下光合速率(放氧速率)显著高于典型的陆生植物(香樟(Cinnamomum camphora(L.) Presl.)和马唐(Digitaria sanguinalis (L.)Scop.)) (3) 在长期水淹的条件下,秋华柳和野古草仍具有水下光合的能力.在水淹60 d后,水淹2 m的秋华柳和野古草植株的水下放氧速率显著低于对照植株的水下放氧速率,但仍具有水下光合的能力,其水下光合速率分别为0.202 μmol · m-2 · s-1和0.139 μmol · m-2 · s-1.同时,研究也表明在水淹40 d和60 d后,秋华柳表现出比野古草强的水下光合能力.研究表明,秋华柳和野古草在存活率和水下光合方面对长期水淹表现出良好的适应性,是可以用于三峡库区消落区植被构建的优良植物物种.  相似文献   
112.
目的:利用慢病毒载体建立稳定表达猪载脂蛋白B mRNA编辑酶催化多肽样蛋白3F(pAPOBEC3F,简称pA3F)的PK15细胞系。方法:以实验室前期构建的pBPLV-flag-pA3F质粒为模板,PCR扩增pA3F基因,克隆到pLenti-Puro-3Flag载体构建成pLenti-Puro-pA3F-3Flag质粒,Western印迹鉴定其在HEK293T细胞中的表达;将pLenti-Puro-pA3F-3Flag质粒与包装载体共转染HEK293T细胞,包装成Lenti-pA3F慢病毒并测定病毒滴度;将Lenti-pA3F慢病毒感染PK15细胞,通过嘌呤霉素压力筛选并结合有限稀释法,筛选稳定表达pA3F的细胞单克隆株,最终Western印迹检测细胞单克隆株中pA3F的表达。结果:菌落PCR和序列测定表明pLenti-Puro-pA3F-3Flag质粒构建正确,Western印迹显示该质粒可在HEK293T细胞中表达pA3F蛋白;包装了Lenti-pA3F慢病毒,滴度为1.32×10~8TU/mL,慢病毒感染PK15细胞后可检测到pA3F蛋白的表达;经Western印迹鉴定,筛选得到的单克隆细胞可稳定表达pA3F蛋白。结论:建立了稳定表达pA3F的PK15细胞单克隆株,为进一步深入研究猪内源性反转录病毒在pA3F作用下的免疫逃逸机制奠定了基础。  相似文献   
113.
丹江口水库马口鱼肠道寄生蠕虫群落结构   总被引:3,自引:1,他引:3  
从2004年8月到2005年11月在丹江口水库调查的847尾马口鱼(Opsariichthys bidens)肠道内共获得寄生蠕虫14种,其中线虫7种,复殖吸虫4种,棘头虫2种,绦虫1种。该寄生蠕虫群落以广谱性寄生虫为主。杜父鱼驼形线虫(Camallanus cotti)、鱊头槽绦虫(Bothriocephalus acheilognathi)、卡斯杆咽线虫(Rhabdochona cascadilla)和木村小棘吻虫(Micracanthorhynchina motomurai)为群落的核心种。研究结果表明,寄生蠕虫群落随着马口鱼的体长和食性的改变而发生显著的变化。群落核心种的感染强度与马口鱼体长呈显著相关关系。种间相关性分析表明群落结构呈非随机组合,种间感染强度存在显著的相关性。同时群落种间关系受到马口鱼的体长和食性以及季节变化的显著影响。马口鱼肠道寄生蠕虫群落在宿主较大个体或夏秋季节中更容易形成显著的种间相关性。  相似文献   
114.
115.
Rice planthoppers are notorious plant sap‐feeding pests which cause serious damage. While several microbes in rice planthoppers have been broadly characterized, the abundance and diversity of bacteria and fungi in field planthoppers are largely unknown. This study investigated the bacterial and fungal community compositions of Chinese wild rice planthoppers Laodelphax striatellus and Sogatella furcifera using parallel 16S rRNA gene amplicon and internal transcribed space region sequencing. The bacteria varied significantly between the species and were partitioned significantly by sex, tissues and host environments in each species. The majority of bacteria were affiliated with the genera Wolbachia, Cardinium, Rickettsia and Pantoea. The abundance of Wolbachia was negatively correlated with that of Cardinium in both planthopper species. Compared with bacteria, the abundance and diversity of fungi did not differ between sexes but both were enriched in the gut. The bacterial community as a whole showed no significant correlation with the fungal community. The majority of fungi were related to Sarocladium, Alternaria, Malassezia, Aspergillus and Curvularia. A phylogenetic analysis revealed that these fungi were closely related to botanic symbionts or pathogens. Our results provide novel insights into the bacteria and fungi of rice planthoppers.  相似文献   
116.
四川石棉县蝴蝶资源调查报告   总被引:1,自引:0,他引:1  
彭徐  雷电 《四川动物》2007,26(4):903-905
报道四川石棉城区及5个乡的蝶类调查情况。通过10多年的调查和标本采集,获标本600余号,整理出10科99种。  相似文献   
117.
In this study, we retrospectively analysed a total of 605 clinical isolates from six West or Central African countries (Benin, Cameroon, Central African Republic, Guinea-Conakry, Niger and Senegal). Besides spoligotyping to assign isolates to ancient and modern mycobacterial lineages, we conducted phenotypic drug-susceptibility-testing for each isolate for the four first-line drugs. We showed that phylogenetically modern Mycobacterium tuberculosis strains are more likely associated with drug resistance than ancient strains and predict that the currently ongoing replacement of the endemic ancient by a modern mycobacterial population in West/Central Africa might result in increased drug resistance in the sub-region.  相似文献   
118.
A feeding experiment with piglets was performed to examine the efficacy of a wet preservation of Fusarium (FUS)-contaminated maize with sodium sulphite (SoS) based on deoxynivalenol (DON) and zearalenone (ZEN) residue levels in urine, bile and liquor and health traits of piglets. For this purpose, 80 castrated male piglets (7.57 ± 0.92 kg BW) were assigned to four treatment groups: CON? (control diet, with 0.09 mg DON and <0.01 mg ZEN/kg diet), CON+ (diet CON?, wet-preserved with 5 g SoS/kg maize; containing 0.05 mg DON and <0.01 mg ZEN/kg diet), FUS? (diet with mycotoxin-contaminated maize; containing 5.36 mg DON and 0.29 mg ZEN/kg diet), and FUS+ (diet FUS?, wet-preserved with 5 g SoS/kg maize; resulting in 0.83 mg DON and 0.27 mg ZEN/kg diet). After 42 d, 40 piglets (n = 10 per group) were sampled. A clear reduction of DON levels by approximately 75% was detected in all specimens of pigs fed diet FUS+. ZEN was detected in all urine, bile and liquor samples, while their metabolites were only detectable in urine and bile. Additionally, their concentrations were not influenced by SoS treatment. Among the health-related traits, feeding of FUS diets increased the total counts of leukocytes and segmented neutrophil granulocytes irrespective of SoS treatment. SoS treatment increased the total blood protein content slightly with a similar numerical trend in albumin concentration. These effects occurred at an obviously lower level in FUS-fed groups. Moreover, SoS treatment recovered the reduction of NO production induced by feeding diet FUS? indicating an effect on the redox level. As this effect only occurred in group FUS+, it is obviously related to the adverse effects of the Fusarium toxins. In conclusion, treatment of FUS-contaminated maize with SoS decreased the inner exposure with DON as indicated by the lower DON levels in various piglet specimens. However, health-related traits did not consistently reflect this decreased exposure.  相似文献   
119.
Filippi syndrome is a rare, presumably autosomal-recessive disorder characterized by microcephaly, pre- and postnatal growth failure, syndactyly, and distinctive facial features, including a broad nasal bridge and underdeveloped alae nasi. Some affected individuals have intellectual disability, seizures, undescended testicles in males, and teeth and hair abnormalities. We performed homozygosity mapping and whole-exome sequencing in a Sardinian family with two affected children and identified a homozygous frameshift mutation, c.571dupA (p.Ile191Asnfs6), in CKAP2L, encoding the protein cytoskeleton-associated protein 2-like (CKAP2L). The function of this protein was unknown until it was rediscovered in mice as Radmis (radial fiber and mitotic spindle) and shown to play a pivotal role in cell division of neural progenitors. Sanger sequencing of CKAP2L in a further eight unrelated individuals with clinical features consistent with Filippi syndrome revealed biallelic mutations in four subjects. In contrast to wild-type lymphoblastoid cell lines (LCLs), dividing LCLs established from the individuals homozygous for the c.571dupA mutation did not show CKAP2L at the spindle poles. Furthermore, in cells from the affected individuals, we observed an increase in the number of disorganized spindle microtubules owing to multipolar configurations and defects in chromosome segregation. The observed cellular phenotypes are in keeping with data from in vitro and in vivo knockdown studies performed in human cells and mice, respectively. Our findings show that loss-of-function mutations in CKAP2L are a major cause of Filippi syndrome.  相似文献   
120.
The G protein-coupled receptor 30 (GPR30) has been claimed as an estrogen receptor. However, the literature reports controversial findings and the physiological function of GPR30 is not fully understood yet. Consistent with studies assigning a role of GPR30 in the cardiovascular and metabolic systems, GPR30 expression has been reported in small arterial vessels, pancreas and chief gastric cells of the stomach. Therefore, we hypothesized a role of GPR30 in the onset and progression of cardiovascular and metabolic diseases. In order to test our hypothesis, we investigated the effects of a high-fat diet on the metabolic and cardiovascular profiles of Gpr30-deficient mice (GPR30-lacZ mice). We found that GPR30-lacZ female, rather than male, mice had significant lower levels of HDL along with an increase in fat liver accumulation as compared to control mice. However, two indicators of cardiac performance assessed by echocardiography, ejection fraction and fractional shortening were both decreased in an age-dependent manner only in Gpr30-lacZ male mice. Collectively our results point to a potential role of Gpr30 in preserving lipid metabolism and cardiac function in a sex- and age-dependent fashion.  相似文献   
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