966 resultados para Hemoglobin A2


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The present communication deals with the feeding trials of brown (Sargassum bovianum), green (Caulerpa faridii) and red (Gracilaria corticola) seaweeds in albino rats for a period of thirty days in order to investigate their digestibility and acceptability as supplementary food for animals. The parameters used were: changes in blood hemoglobin, ESR, MCHC, PCV and plasma vitamin levels. The result revealed that all the three species of seaweeds had acceptability up to 5% level, as no ill effect was noted during the experiment. But at 10% and 20% levels, marked changes were observed in blood parameters with diarrhea, vomiting and convulsions indicating possibilities of either tissue and muscular dystrophy, gastrointestinal tract necrosis or functional disorder of central nervous system. A heavy mortality was noted due to excessive water loss through diarrhea and vomiting. However, no mortality was observed after 22nd day at both 10% and 20% levels with subsided clinical signs. The results suggest that these three seaweed species could be used safely as a supplementary food, in native form, in animals at low concentrations.

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森林作为陆地生态系统的主体,在全球陆地碳循环中起着决定性作用。实测和模型研究均表明北半球的森林是重要的大气CO2汇,在缓解全球碳收支失衡中发挥着关键作用。过去几十年北半球所经历的显著气候变化,已经很大地改变了陆地生态系统的碳平衡状况。随着未来100年气候变化继续增大,对未来气候变化下森林生态系统碳平衡的预测研究就尤为重要。 北京山区森林属于典型的暖温带森林生态系统,前人对本区森林的植被特征、生态系统结构和功能、养分循环以及长期动态变化等都进行了深入的研究。然而长期的人类活动已使本区原生的地带性植被破坏殆尽。因此,对该区域森林生态系统碳平衡的模拟研究可以帮助我们认识其生态系统碳平衡变化特点及未来气候变化对其潜在的影响。 本研究采用LPJ-GUESS植被动态机理模型,利用IPCC于2000年发布的《排放情景特别报告》(SRES)的A2和B2两种情景下不同气候模式对华北地区未来100年温度和降水预测的平均值以及相应大气CO2浓度变化情景进行驱动,模拟北京山区未来100年暖温带森林生态系统的净初级生产力和碳平衡,尽可能真实地反映未来百年的变化趋势。通过比较当前和未来气候情景下北京山区以辽东栎(Quercus liaotungensis)为优势种的落叶阔叶林、以白桦(Betula platyphylla)为主的落叶阔叶林和油松(Pinus tabulaeformis)为主的针阔混交林三种典型暖温带森林生态系统的碳平衡差异,了解未来北京山区这三种暖温带森林生态系统的碳源汇功能,认识气候变化和大气CO2浓度升高对净初级生产力(Net primary productivity, NPP)、净生态系统碳交换(Net ecosystem exchange, NEE)、土壤异养呼吸(Heterotrophic respiration, Rh)和碳储量(Carbon biomass, C biomass)的影响,以及不同生态系统碳平衡对气候变化响应的异质性。 结果表明,未来100年两种气候情景下三种森林生态系统的NPP和Rh均增加,并且A2情景下增加的程度更大。由于三种生态系统树种组成的不同,未来气候情景下各自NPP和Rh增加的比例不同,导致三者NEE的变化也相异:100年后辽东栎林由碳汇转变为弱碳源,白桦林仍保持为碳汇但功能减弱,油松林成为一个更大的碳汇。三种森林生态系统的碳生物量在未来气候情景下均增大,21世纪末与20世纪末相比:辽东栎林在A2情景下碳生物量增加的比例为27.6%,大于B2情景下的19.3%;白桦林和油松林在B2情景下碳生物量增加的比例分别为34.2%和52.2%,大于A2情景下的30.8%和28.4%。各森林类型碳平衡状况不同,原因除气候因素外,主要是由于树种组成的差异所导致。SRES A2和B2两种气候情景相比,相对较低的排放情景(B2)下,生态系统有更高的碳储量。

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The sublethal exposure (0.24 ppm) of Nuvan on some biochemical compositions such as serum protein, blood glucose, glutamate oxaloacetate transaminase (AST) and glutamate pyruvate transaminase (ALT) and on some hematological parameters such as red blood corpuscles (RBC), white blood corpuscles (WBC), hemoglobin content (Hb), mean corpuscular concentration (MCV), mean corpuscular hemoglobin concentration (MCHC) of Catla catla fingerlings were studied. The hematological and biochemical parameters evoked a significant reduction (excepting MCV, ALT and AST which is significantly increased) with increasing days of Nuvan exposure.

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高等植物光系统II的捕光天线蛋白(LHC II)在光能的吸收、传递和调节激发能在两个光系统之间的分配以及维持类囊体膜的垛叠等方面都起着重要的作用,因而得到了广泛的研究。目前普遍认为LHC II在植物体内是以三聚体的形式存在并行使功能的,但也有研究者发现了单体和寡聚体等多种形式的LHC II。本论文以菠菜为研究对象,采用改进的方法从类囊体膜中提取纯化了LHC II三聚体,对膜脂和色素在三聚体形成和蛋白空间结构中的影响,以及不同聚集态LHC II组成、结构和功能的差异进行了较系统的研究。此外,还将Lhcb2基因反向插入到烟草中,利用转基因植物来研究其生理功能。获得了如下结果: 1,采用改进的方法从菠菜类囊体膜中分离纯化了LHC II。与改进前比,其流程可以缩短2小时且产率也有明显的提高。SDS变性电泳和Triton X-100非变性电泳的检测结果表明,此样品纯度较高,是由三条分子量分别为29KD、28KD和26KD的多肽组成的异质三聚体。同时样品的吸收光谱和荧光光谱分析结果也与前人的报道一致。 2,分析了LHC II三聚体中的膜脂和脂肪酸组成及含量。与PSII相比,LHC II含有相同的四种膜脂:MGDG、DGDG、PG和SQDG。但LHC II中PG的含量是PSII的两倍,说明PSII中的PG主要富集在外周天线区域。同时PG中含有特异的反式十六碳一烯酸,且含量很高。用专一消化PG上Sn-2位脂肪酸链的磷脂酶A2(PLA2)处理LHC II三聚体,然后再加入PG重组的方法证明了含十六碳一烯酸的PG在三聚体结构的维持中起着至关重要的作用。去掉PG后, LHC II三聚体的结构受到了影响,部分解聚成了单体,同时其光谱特性也发生了变化,表现为叶绿素b分子的吸收峰及其激发的荧光发射峰都明显下降。回加PG则可使解聚的单体又重新聚集成三聚体。 3,分别用电洗脱和蔗糖密度梯度离心两种方法分离了LHC II三聚体、二聚体和单体。两者比较,电洗脱对样品的破坏较大,而蔗糖密度梯度离心更加温和,对蛋白上结合的色素影响不大。系统研究了不同聚集态LHC II的组成和光谱特性后发现,三种聚集态的LHC II有相同的多肽组成,并且都结合着5种色素,但是色素的含量差异较大。二聚体和单体中,叶绿素b和类胡萝卜素分子的含量比三聚体的低很多,此外,单体叶绿素a分子的含量也明显减少。对三种聚集态LHC II的各种光谱特性进行分析的结果表明,由于叶绿素b和类胡萝卜素分子含量较少,二聚体和单体中叶绿素b和类胡萝卜素的吸收均有所下降,而且从类胡萝卜素到叶绿素b以及从叶绿素b到叶绿素a的能量传递效率都低于LHC II三聚体,总体表现为三聚体 > 二聚体 > 单体。此外,不同单体之间叶绿素a到叶绿素a的能量传递也被破坏。推测三种聚集态LHC II在吸能、传能和结构上的差异,可能是植物适应不同外界环境的一种调控机制。 4,模拟体内过程,在体外将大肠杆菌中表达的Lhcb2蛋白和色素进行重组,以此来研究色素与蛋白组装过程中蛋白二级结构和色素结合状态的变化。结果表明色素在脱辅基蛋白的体外重折叠中至关重要。在与色素重组的过程中,蛋白二级结构中-螺旋含量逐渐上升并最终接近天然水平,而无规卷曲逐渐减少。从光谱的变化可以看出,色素分子与蛋白的结合经历了一个由无序到有序的过程,色素蛋白复合物的光谱信号由弱变强,重组得到的样品与天然LHC II十分相似。 5,为了更好地研究LHC II异质三聚体中单体可能具有的独特生理功能,建立了Lhcb2基因的反义抑制植物表达载体pBI-antiLhcb2,用根癌农杆菌介导法转化烟草,获得了转基因植株。酶切和PCR鉴定证明,Lhcb2基因已经成功地插入到烟草里。进一步的分子鉴定和生理生化功能分析还在进行中。

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利用经酸处理的Sepharose 4B为层析介质,以含0.2mol/L半乳糖,pH7.4台氏液作为洗脱液,从广西产金环蛇(Bungarus fasciatus)蛇毒中一步分离得到一种磷脂酶A_(2)。用SDS-聚丙烯酰胺凝胶电泳测定其分子量为14kDa。N端部分序列测定表明,所分离得到的磷脂酶A_(2)其N端16个氨基酸残基序列与已报道的金环蛇蛇毒磷脂酶A_(2)同功酶Ⅵ(Lu&Lo,1978)一致。该酶糖含量较高,为13.4%;具有弱的磷脂酶A_(2)活性,无毒,也无溶血和出血毒活性。

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In mammals, trefoil factor family (TFF) proteins are involved in mucosal maintenance and repair, and they are also implicated in tumor suppression and cancer progression. A novel two domain TFF protein from frog Bombina maxima skin secretions (Bm-TFF2) has been purified and cloned. It activated human platelets in a dose-dependent manner and activation of integrin a(11b)beta(3) was involved. Aspirin and apyrase did not largely reduce platelet response to Bm-TFF2 (a 30% inhibition), indicating that the aggregation is not substantially dependent on ADP and thromboxane A2 autocrine feedback. Elimination of external Ca2+ with EGTA did not influence the platelet aggregation induced by Bm-TFF2, meanwhile a strong calcium signal (cytoplasmic Ca2+ release) was detected, suggesting that activation of phospholipase C (PLC) is involved. Subsequent immunoblotting revealed that, unlike in platelets activated by stejnulxin (a glycoprotein VI agonist), PLC gamma 2 was not phosphorylated in platelets activated by Bm-TFF2. FITC-labeled Bm-TFF2 bound to platelet membranes. Bm-TFF2 is the first TFF protein reported to possess human platelet activation activity. (c) 2005 Elsevier Inc. All rights reserved.

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榕树与其传粉小蜂形成了高度专一的互惠共生系统。非传粉小蜂则是该系统的资源掠夺者, 但它与 该系统共存的机制仍不清楚。于2003 年12 月—2004 年4 月在西双版纳以聚果榕( Ficus racemosa L. ) 为材料, 研究了寄生在聚果榕榕果内的5 种非传粉小蜂的食性及相互关系, 以探讨非传粉小蜂与榕树- 传粉小蜂系统共 存的机制。结果表明: 寄生在聚果榕榕果内的5 种非传粉小蜂中, 仅Platyneura testacea Motschulsky 和Platyneu2 ra mayri Rasplus 能刺激子房发育成瘿花, 是造瘿者; Apocrypta sp . , Apocrypta westwoodi Grandi 和Platyneura a2 graensis Joseph 不能刺激子房发育成瘿花, 是拟寄生者。传粉小蜂的拟寄生者和造瘿者对传粉小蜂有负的影响, 但在蚂蚁和造瘿者的拟寄生蜂作用下, 这种负面影响并不显著, 而且它们对榕树繁殖没有显著影响。对小蜂自 然种群的分析表明, 传粉小蜂处于优势地位。说明在自然情况下传粉小蜂的拟寄生者和造瘿者的种群维持在一 个较低水平, 对榕树- 传粉小蜂系统稳定性影响较小, 故能与之长期共存。

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A fragment of mitochondrial DNA (mtDNA) control region (similar to700 bp) was sequenced in 104 individuals from 20 breeds (three Chinese domestic breeds, five recently derived breeds and 12 introduced breeds) of domestic rabbits, Oryctolagus cuniculus . Nineteen sites were polymorphic, with 18 transitions and one insertion/deletion, and eight haplotypes (A1, A2, A3, A4, A5, A6, A7 and A8) were identified. Haplotype A1 was the most common and occurred in 89 individuals. In the 25 Chinese rabbits, only haplotype A1 was observed, while four haplotypes (A1, A3, A5 and A6) were found in 26 recently derived individuals. Haplotype A2 was shared by seven individuals among three introduced strains. The other six haplotypes accounted for 0. 96-1. 92% of the animals. Combined with the published sequences of European rabbits, a reduced median-joining network was constructed. The Chinese rabbit mtDNAs were scattered into two clusters of European rabbits. These results suggest that the (so-called) Chinese rabbits were introduced from Europe. Genetic diversity in Chinese rabbits was very low.

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在作为成瘾检测手段的条件化位置偏爱模型中,环境背景和成瘾药物间的关联性学习起着关键的作用.突触可塑性作为学习记忆可能的物质基础,在药物成瘾方面的研究也越来越多,但其表现形式,长时程增强(LTP)或者长时程抑制(LTD)在成瘾过程中所发挥的具体作用尚不得而知.因此,本文利用生物信息学手段,设计并合成了旨在分别阻断LTP和LTD的干扰肽,研究其对小鼠吗啡条件化位置偏爱的影响.结果发现,干扰肽Pep-A2和Pep-A3能够分别特异地阻断海马CA1区的LTP和LTD,在测试前尾静脉注射具有穿膜特性的LTP/LTD特异性干扰肽(Tat-A2/Tat-A3),均能阻断或损伤吗啡诱导的条件化位置偏爱的表达.此发现提示我们,LTP和LTD在成瘾性异常记忆的过程中均发挥着重要的作用.

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This study was done in Shahid Kiani Marine Aquaculture Development Center, Choebde, Abadan in order to evaluate the effects of Pediiococcus acidilactici, Lactococcus lactis and vitamin C on growth performance, survival, enzymatic activities and immune responses of L. vannamei during three months. Treatments were included control group, Pediiococcus and Lactococcus treatments which fed with diet containing 1×10P9P cfu gP_1P bacteria and vitamin C. At the end of the experiment, the growth factors, immune parameters, digestive enzymes, intestinal, histology of intestine, carcasses and microbial flora (bacterial total count and lactic acid count) were evaluated. The results indicated that administration of lactobacillus had significant effects on the growth factors as the highest weight, increase specific growth rate, relative growth rate, feed conversion ratio and protein efficiency in the shrimps received pediococcus and then Lactococcus (P<0.05). The best immune function was also observed in the shrimps fed by probiotics, so that proteins and hemoglobin̛ hemolymph, phenoloxidase activity and challenged with V. parahaemolyticus showed a statistical difference comparing to the control group and the group received vitamin C (P<0.05). Some digestive enzymes, in pediococcus treatment showed a significant increase when compared to other treatments (P<0.05). Significant changes in bacterial intestinal flora were observed in probiotic groups compared with control and vitamin C groups (P < 0.05). Histological results showed the positive effects of probiotics in the gut (P < 0.05). While these supplements cannot caused to significant impacts on the shrimp carcass composition (P ˃ 0.05). As a result pediococcus group had the best performance among treatments.

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Seasonal sampling from 40 immature Caspian salmon were performed in summer, autumn, winter and spring. The maximum ranges of RBC counts, Hct, Hb, WBC count and clotting times were observed in spring, summer, spring, spring and winter, respectively. The minimum amounts of these factors were counted in summer, winter, winter, winter and winter, respectively. Blood Samples were taken from healthy smolt, immature and adult Caspian salmon in spawning time. Hematological determinations and biochemical serum analysis were performed in 101 fish in the three samples. The ranges of hematological values for sample mean were counted. Red blood cell counts were 866600 mm3 and 1259400 mm3 in smolt and adult respectively. Hematocrit was 48.39% in smolt and 44.29% in adult. Hemoglobin was 8.85 gr/dl in smolt and 10.91 gr/dl in adult. White blood cell count was 8781.58 mm3 in smolt and 5217.55 mm3 in adult and mean were differential of WBC, Lymphocyte 90.57%in smolt and73.22% in adult. Neutrophil was 5.12% in smolt and 16.92% in adult, Monocyte were 1.27% in smolt and 4.24% in adult, Clotting time was 282.34 Seconds in smolt and 291.47 seconds in adult MCV, MCH and MCHC also meagered in smolt and adult. Biochemical parameter in immature and mature Caspian salmon meagered .Glucose concentration was 2.97 mmol.l- in immature and 1.99 mmol.l- in mature .Cholesterol concentration was 4.26 mmol.l- in immature and 7.06 mmol.l- in mature. Triglyceride amount was 2.35 mmol.l- in immature and 2.47 mmol.l- in mature and Calcium was 2.47 in immature and 2.61 mmol.l- in mature. An in situ study was made on erythrocytic isoantigens and hetero-antigen and their corresponding iso-and hetero-antibodies of sera by means of hemoagglutination tests on the blood sample, of 450 immature and 50 mature Caspian salmon. The absence of erythrocyte iso-antigens and hetero-antigen and their corresponding iso-and hetero-antibodies were shown by the experimental. It could be indicated an intra-specific variation and differences in species for kelardasht hatchery.

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Prebiotics are non-digestible food ingredients that profitably affect the host by selectively stimulating the growth and /or activation of one or a limited number of bacteria in the intestine that can enhance host health status. Immunoster (IS) and Immunowall (IW) are prebiotics and immunostimulants derived from the outer cell wall of brewers yeast, Saccharomyces cerevisiae. These substances contain MOS and �-glucans. After a four-week acclimatization period to rearing conditions and basal diet, 450 farmed great sturgeon juveniles weighing 95.58 ± 9.38 g were randomly distributed into 15 fiberglass tanks (2 × 2 × 0.53 m) in five treatments (Control, IS 1%, IW 1%, IS 3%, and IW 3%) in three replicates (completely randomized design) and kept at a density of 30 fish per tank for a period of 8 weeks at water temperature 20.55 ± 5.11ºC, dissolved oxygen 6.73 ± 0.35 mg L-1 and pH 7.92 ± 0.09. IS and IW were added at two levels of 1% and 3% to the basal diet in place of cellulose, except the control. At the beginning, in the middle and at the end of the trial, carcass analysis was done to determine the moisture, protein, fat, ash, and total carbohydrate. Also, blood samples were collected to measure hematological, biochemical and immune indices. At the end of the trial, final weight, final length, body weight increase (BWI), specific growth rate (SGR), average daily growth (ADG), protein efficiency ratio (PER), feed conversion ratio (FCR), and condition factor (CF) in fish fed on IS and IW in both levels 1% and 3% showed some differences. These differences were significant in IS 3% and IW 1% and 3% compared with the control (P<0.05). HSI showed no significant difference (P>0.05) and survival rate was 100% in all treatments. Crude protein of carcass in fish fed on IS and IW at 1% and 3% showed an increase in comparison with the control. There was significant difference between IS 3% and the control in crude protein of carcass (P<0.05). Fish fed on IS and IW at 1% and 3% showed various results in hematological and biochemical factors. It was observed significant difference in MCV between IW 1% and IS 3% compared with the control (P<0.05). Although there was an increase in values of hematocrit, hemoglobin (except IS 1%), WBC (except IW 3%), MCH, neutrophil, total protein, albumin (except IS 3%), K+, and lysozyme in fish fed on IS and IW compared with the control, it was no significant (P>0.05). The maximum count of WBC and the highest value of Ca2+ were seen in IW 1%. The maximum count of lymphocyte, the highest values of total protein, albumin and IgM were recorded in IW 3%. IS 1% had the maximum count of neutrophil and the highest concentration of lysozyme. Based on obtained results, it can be declared that IS and IW at two levels of 1% and 3% can enhance growth performance and feed efficiency and also improve some hematological, biochemical, and immune indices in farmed great sturgeon juveniles.

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In this study the process of female gray mullet brooders was carried out by using histological study and masurment of sex steroids. Results of histological studies showed that oocyte of gray mullet brooders in Gomishan Rearing Center conditions of develop to the end of yolk globule stage. The results were observed with oocyte in chromatin nucleolar stage (first stage) with means of diameter of 20 p m, in August, perinucleolar stage (second stage) in September with mean diameter of 87 p m, yolk vesicle stage (third stage) in October with mean diameter 200 p m and yolk granules stage (forth stage) from October to November with average diameter of 180 — 650 p m. For the reason of stopping oocyte develop at the end of fourth stage, hormonal induction to final oocyte maturation and ovulation was used. For this purpose, carp pituitary , HCG and LRH-A2 with different combinations were used in two stages, second injection was used 24 hours after first injection. 15 females brooders were divided in 5 groups, different hormonal combinations were injected to four groups and to fifth group as control, only saline, was injected. The process of female brooder rippening in hormonal induction was studied via masurment of sex steroids including 17 a - hydroxy progestrone, estradio1-17)6 and testosterone. Blood samples were collected from caudal vein during first injection, 24, 30 and 48 hours after the first injection. At the same time, for distinguishing histological changes the sample has been attained from the gonads Sex stroid fluctuation patterns in different brooder groups that injected hormon were similar, however hormonal composition had similar effects. All brooder that their oocyte in the beginning of hormonal injection were At the end of fourth stage with oocyte diameter average of 600 p m received to final maturation and ovulation. The brooder that its oocytes were At the begining or mid-fourth stage did not show ovulation but hormonal induction caused oocyte develop at the beginning of fifth stage. Study of 17-hydroxy progestrone fluctuation showed that the maximum level of this steroid (0.347 ng/ml) measured 30 hours after the first injection and was significantly higher (p< 0.05) than those of control group. So, 17-hydroxy progestrone is probably precursor of maturation inducing steroid (MIS). However the maximum level of that observed was coincident with germinal vesicle breakdown, oil droplets coalescence and dissolution of yolk granuls The maximum levels of esteradiol— 17/0 and testosterone (3.778 and 16.801ng/ml,respectively) in spawned brooders,were observed 24 hours after the first injection. levels of those steroids were significantly higher (p<0.05) than control group. Maximum level of sex steroids in the brooders that did not spawn to the end of treatment was observed with more delay than those in spawned brooders. Therefor maximum level of 17a-hydroxy progestrone (0.264 ng/ml) in those brooders observed in fourth sampling time and the maximum levels of estradio1-17a and testosterone (2.944 and 18.993 ng/ml, respectivly)observed in third sampling time that was significantly higher (p<0.05) than those of control group. For the study of stress effect on brooders during the hormonal induction, level of cortisol was measured in every sampling time. level of cortisol had high fluctuation that showed handling level and stress effect on brooders. However maximum level of cortisol in majority of brooders was dominant in third sampling time that was coincident with final maturation.

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One of the most important marine ecologic phenomenon , is the study of animal community among the bed or benthic fauna. Macrobenthoses are the graet part of the benthic faune , that are more biomasses than meiofauna and microfauna. To study polychaetes diversity of Mangroves, located in Khoore-Khooran , sampling was conducted on a bimonthly and carried out from December 2001 to October 2002. Bottom samples were collected by Van Veen grab (0.025 m2)at 6 station from 2 transect Insitu measurement of temperature , pH , Do and salinity were done . Atotal of polychaetes werw identified within study 32 Family and 43 Genus . Cirriphormia and Nephtys were the most dominant genus in the studies . The range fomumerical abundance of polychaets was between 3006 per m2 in the station A3 to 559individual per mein the station A1 and the variation was done to different bottom , texture the variable environment conditions govrtneng the different parts of each creeks as well as within creeks . Application of diversity indices (Shannon H') on the dominant polychates assambladges has higher H' in the Azar and lower 1-1/ in the Mehr . and the stations B3 has the highest H' and the station A2 has the lowest H' Application of diversity and Richness, Evennes were studied and showed that the station A3 has the lowest evenness and the most individual , and station A1 has the middle pollution.

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Objective To confirm the genetic relation between Giardia lamblia (G. lamblia) isolates from different geographic regions of China and other countries. Methods Genomic DNA were extracted from the trophozoites or cysts of Giardia lamblia. The triose phosphate isomerase (tim) gene was amplified using polymerase chain reaction (PCR) technique. PCR products were digested with endonuclease and sequenced. The data of sequencing were analyzed with the DNAstar software and compared with that of the isolates acquired from GenBank. Results Of nine isolates of Giardia lamblia from China (C1, C2, CH2 and CH3), Cambodia (CAM), Australia (A1 and A2) and America (BP and CDC), respectively, 3 (A1, A2 and CAM) fit into Group 1 (WB), 2 (CH2 and CH3) into Group 2, and 4 (C1, C2, BP and CDC) into Group 3 (GS). The results confirmed the genetic relatedness of G. lamblia isolates from all over the world. Conclusion Genotyping isolates of G. Lamblia provides important information for establishing the phylogenetic relationship or for the epidemiological evaluation of the spreading of this organism.