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741.
Topmouth culter (C. alburnus) is an important commercial fish in China. We compared the nucleotide variations in the mtDNA genomes among three geographical groups of Culter alburnus: Liangzi Lake, Hubei Province (referred to as LZH); Taihu Lake, Jiangsu Province (TH); and Poyang Lake, Jiangxi Province (PYH). The similarity of whole mtDNA genomes ranged from 0.992 to 0.999. The similarity among 13 protein-coding genes, 2 rRNA genes, and the D-loop sequences was found to range from 0.982 to 0.996. This is useful data for future designing work for making specific molecular marker for distinguishing individuals of C. alburnus from the three geographical groups. An extended termination-associated sequence (ETAS) and several conserved blocks (CSB-F, CSB-E, CSB-D, CSB1, CSB2, and CSB3) were identified in the mtDNA control regions. A phylogenetic analysis shows a monophyletic relationship of the LZF-female and the LZF-male. However, the analysis also showed paraphyletic relationships for the other two geological groups. This result will be useful for the future breeding work of C. alburnus.  相似文献   
742.
DMD的ATP酶组织化学研究   总被引:1,自引:0,他引:1  
目的观察DMD(Duchenne muscular dystrophy)患者病变肌肉的酶组织化学病理改变,加深对其发病机制和预后的认识.方法对5例Duchenne型肌营养不良症患者进行肌肉活检,标本经处理,分别在HE染色、改良Gomori三色染色以及ATP酶染色(pH9.4和pH4.3)下进行观察,研究病变肌肉酶组织化学的病变特征及其意义.结果在DMD组织中肌纤维大小不等,肌纤维圆形化,炎性细胞浸润,并可见到不透光纤维.在再生肌纤维中可见到IIc型纤维.结论 DMD病变组织中纤维坏死显著,伴有不同程度的再生,故临床症状严重,病程短,预后较差.  相似文献   
743.
动物行为是动物对外界环境变化和内在生理活动改变所做出的整体性反应,研究动物行为节律是了解其活动特征时空变化及影响因素的重要内容。2015年9月15日-10月6日采用直接观察法、2016年5-12月采用红外相机监测技术,在内蒙古赛罕乌拉国家级自然保护区对中华斑羚Naemorhedus griseus的行为节律进行观察,了解其行为适应对策。记录了7类中华斑羚行为,包含27种具体行为内容,通过对每种行为进行描述,建立了行为谱。中华斑羚的行为节律具有月度变化特点,摄食行为11月比例最高、站立行为8月比例最高、移动行为12月比例最高,发情行为在10月、12月出现。研究表明,中华斑羚的行为特点是对该区域生态条件与捕食风险的有效适应,对于自然保护区管理部门采取救护措施、促进隔离种群恢复具有指导作用。  相似文献   
744.
研究海胆黄多糖SEP对S180肉瘤的抑制作用及初步机制。MTT法检测SEP对体外培养的S180细胞生长的抑制作用;建立小鼠S180肉瘤模型观察SEP抗肿瘤活性;检测SEP协同ConA/LPS刺激小鼠脾淋巴细胞增殖作用;同时,考察SEP对NK细胞和杀伤性T淋巴细胞(cytotoxic T lym-phocyte,CTL)活性的影响;碳粒廓清检测SEP对小鼠单核巨噬细胞吞噬功能的影响。研究表明,海胆黄多糖SEP高中低剂量(16、8、4 mg/kg)显著抑制小鼠180实体瘤生长,增加小鼠脾指数和胸腺指数,协同ConA/LPS刺激小鼠脾淋巴细胞增殖,提高小鼠NK细胞和CTL活性,增强小鼠单核巨噬细胞的吞噬功能,通过免疫调节提高小鼠免疫功能达到抑制S180作用。  相似文献   
745.

Objective

The present study investigated the prevalence and risk factors for Metabolic syndrome. We evaluated the association between single nucleotide polymorphisms (SNPs) in the apolipoprotein APOA1/C3/A4/A5 gene cluster and the MetS risk and analyzed the interactions of environmental factors and APOA1/C3/A4/A5 gene cluster polymorphisms with MetS.

Methods

A study on the prevalence and risk factors for MetS was conducted using data from a large cross-sectional survey representative of the population of Jilin Province situated in northeastern China. A total of 16,831 participations were randomly chosen by multistage stratified cluster sampling of residents aged from 18 to 79 years in all nine administrative areas of the province. Environmental factors associated with MetS were examined using univariate and multivariate logistic regression analyses based on the weighted sample data. A sub-sample of 1813 survey subjects who met the criteria for MetS patients and 2037 controls from this case-control study were used to evaluate the association between SNPs and MetS risk. Genomic DNA was extracted from peripheral blood lymphocytes, and SNP genotyping was determined by MALDI-TOF-MS. The associations between SNPs and MetS were examined using a case-control study design. The interactions of environmental factors and APOA1/C3/A4/A5 gene cluster polymorphisms with MetS were assessed using multivariate logistic regression analysis.

Results

The overall adjusted prevalence of MetS was 32.86% in Jilin province. The prevalence of MetS in men was 36.64%, which was significantly higher than the prevalence in women (29.66%). MetS was more common in urban areas (33.86%) than in rural areas (31.80%). The prevalence of MetS significantly increased with age (OR = 8.621, 95%CI = 6.594–11.272). Mental labor (OR = 1.098, 95%CI = 1.008–1.195), current smoking (OR = 1.259, 95%CI = 1.108–1.429), excess salt intake (OR = 1.252, 95%CI = 1.149–1.363), and a fruit and dairy intake less than 2 servings a week were positively associated with MetS (P<0.05). A family history of diabetes (OR = 1.630, 95%CI = 1.484–1.791), cardiovascular disease or cerebral diseases (OR = 1.297, 95%CI = 1.211–1.389) was associated with MetS. APOA1 rs670, APOA5 rs662799 and rs651821 revealed significant differences in genotype distributions between the MetS patients and control subjects. The minor alleles of APOA1 rs670, APOA5 rs662799 and rs651821, and APOA5 rs2075291 were associated with MetS (P<0.0016). APOA1 rs5072 and APOC3 rs5128, APOA5 rs651821 and rs662799 were in strong linkage disequilibrium to each other with r2 greater than 0.8. Five haplotypes were associated with an increased risk of MetS (OR = 1.23, 1.58, 1.80, 1.90, and 1.98). When we investigated the interactions of environmental factors and APOA1/C3/A4/A5 gene cluster gene polymorphisms, we found that APOA5 rs662799 had interactions with tobacco use and alcohol consumption (PGE<0.05).

Conclusions

There was a high prevalence of MetS in the northeast of China. Male gender, increasing age, mental labor, family history of diabetes, cardiovascular disease or cerebral diseases, current smoking, excess salt intake, fruit and dairy intake less than 2 servings a week, and drinking were associated with MetS. The APOA1/C3/A4/A5 gene cluster was associated with MetS in the Han Chinese. APOA5 rs662799 had interactions with the environmental factors associated with MetS.  相似文献   
746.
747.
Tian C  Tobler K  Lamb RA  Pinto LH  Cross TA 《Biochemistry》2002,41(37):11294-11300
The M2 protein from influenza A virus has been expressed, purified, and reconstituted into DMPC/DMPG liposomes. SDS-PAGE analysis of reconstituted M2 protein in DMPC/DMPG liposomes demonstrates a stable tetrameric preparation. Circular dichroism spectra of the intact M2 protein in detergent indicate 67% alpha-helix. The uniformly (15)N-labeled M2 protein and both (15)N-Val- and (15)N-Leu-labeled M2 protein have been expressed from defined M9 media. The (1)H-(15)N HSQC (heteronuclear single quantum correlation) solution NMR experiments have been performed on the amino acid specific labeled protein in 300 mM SDS-d(25) micelles, and the data indicate a homogeneous preparation. The reconstituted M2/DMPC/DMPG proteoliposomes were used for preparing uniformly aligned solid-state NMR samples for (15)N-(1)H dipolar/(15)N chemical shift correlation experiments. The spectra support a transmembrane helix in M2 protein having a tilt angle of approximate 25 degrees, quantitatively similar to results obtained on the isolated M2 transmembrane peptide reconstituted in DMPC bilayers (38 degrees ). In addition, the spectra suggest that the tetrameric protein forms a symmetric or at least pseudosymmetric bundle consistent with data obtained by other research groups based on electrophysiological measurements and substituted cysteine scanning mutagenesis experiments that characterize a tetrameric structure.  相似文献   
748.
冠秀芬  李钦 《微生物学报》1990,30(5):397-399
Catechol-1,2-dioxygenase (EC 1.13.11.1) catalyzes the degradation of catechol to cis, cis-muconic acid. The biochemical properties of catechol-1,2-dioxygenase from Pseudomonas putida 84103 were investigated. The optimum pH and temperature is 7.5-8.0 and 25-30 degrees C, respectively. Cu2+, Zn2+ inhibit the enzyme activity. The paper chromatograph and UV absorption spectrum of enzymatic reaction product are accordance with those of the standard muconic acid.  相似文献   
749.
模拟践踏和降水对高寒草甸土壤养分和酶活性的影响   总被引:2,自引:0,他引:2  
为明晰牦牛和藏羊践踏对高寒草甸的分异影响,通过2年模拟践踏和降水双因子控制试验,研究了践踏和降水对高寒草甸土壤养分和酶活性的影响。研究结果表明,践踏处理提高了0—20 cm土层土壤速效氮和速效钾含量,降低了0—20 cm全磷、脲酶和0—10 cm速效磷、碱性磷酸酶和有机质含量,且适度践踏促进了全氮的矿化。随降水强度的增加,0—30 cm土层土壤全氮和0—20 cm全磷和脲酶活性呈单峰曲线的变化态势,在平水下达到峰值;降水显著降低了0—30 cm土层土壤速效氮、磷、钾和0—10 cm土层土壤全钾含量,对土壤有机质含量无显著影响(P0.05)。同一放牧强度下,藏羊践踏区的土壤养分和酶活性优于牦牛践踏区,但差异不显著(P0.05)。综合可得,家畜的践踏作用促进了土壤氮和钾的矿化,抑制了磷的累积且加速了表层土壤有机质的耗竭,降低了土壤脲酶和碱性磷酸酶活性;适度降水提高了土壤全氮、全磷含量及酶活性,降水过多则相反。适度的家畜践踏与降水相耦合下草地土壤的养分循环和酶活性要优于重度践踏和不践踏小区。在对草地的适度放牧利用前提下,应注重土壤含水量和放牧畜种对草地的影响。草地干旱或土壤含水量过高时,应适当减少放牧畜种中牦牛比例增加藏羊比例,以期使草地得到健康可持续发展。  相似文献   
750.
Liu W  Zou D  Wang X  Li X  Zhu L  Yin Z  Yang Z  Wei X  Han L  Wang Y  Shao C  Wang S  He X  Liu D  Liu F  Wang J  Huang L  Yuan J 《Journal of proteome research》2012,11(8):4024-4033
The co-occurrence of L1 and AmpR-L2 with bla(NDM-1) gene with an upstream 250-bp promoter was detected in a clinical isolate of Stenotrophomonas maltophilia DCPS-01, which was resistant to all β-lactams and sensitive only to colistin and fluoroquinolones. To investigate expression of resistance genes and the molecular mechanisms of bacteria resistance to carbapenems, proteomic profiles of the isolate was passaged with and without the drug by using 2D-PAGE. The results showed that 33 genes exhibiting a ≥3-fold change were identified as candidates that may help S. maltophilia survive drug selection. Strikingly, L1 was expressed more highly in cells grown with imipenem, and the abundant NDM-1 further increased, while very little L2 was detected even following induction. Specific activities for β-lactamase revealed that L2 remained at constitutive low levels (10.6 U/mg), while L1 and NDM-1 showed clear activity (69.8 U/mg). Our data support that imipenem could specifically and reversibly induce L1 and NDM-1, which together played key roles in drug resistance in DCPS-01. Although NDM-1 mediated resistance to carbapenems has been found in very few cases, to our knowledge, this is the first proteomics research of S. maltophilia with NDM-1, giving very broad-spectrum antibiotic resistance profiles.  相似文献   
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