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1.
中华稻蝗消化道内分泌细胞的鉴别与定位   总被引:1,自引:0,他引:1  
采用整块组织Grimelius银染法和过氧化物酶标记的链霉亲和素免疫组织化学技术,结合生物统计学分析,对中华稻蝗Oxya chinensis消化道内分泌细胞进行鉴别与定位。结果表明:嗜银细胞分布于中华稻蝗的胃盲囊、中肠和后肠各段,以中肠和直肠中最多(P<0.05), 前肠中未见分布。免疫组织化学法检测出了五羟色胺(5-hydroxytryptamine, 5-HT)、 胃泌素(gastrin, Gas)、 胰高血糖素(glucagon, Glu)和胰多肽(pancreatic polypeptide, PP)细胞, 未检出生长抑素(somatostatin, SS)细胞。免疫阳性细胞分布于中肠和后肠中, 前肠中未见分布。5-HT细胞和Gas细胞均主要分布于胃盲囊、中肠及直肠中,且均以直肠中最多(P<0.05)。Glu细胞在胃盲囊及整个中、后肠均有分布, 在中肠和直肠中最多(P<0.05)。PP细胞主要分布于中肠、回肠和直肠中,中肠中分布密度最大(P<0.05)。本研究显示中华稻蝗消化道中存在多种内分泌细胞,它们的分布情况与其他节肢动物相比存在一定的共性,也有其一定的特异性,可能与中华稻蝗特定的消化道结构和消化生理功能有关。  相似文献   

2.
钟海英  张雅林  魏琮 《昆虫学报》2020,63(4):421-432
【目的】本研究通过合哑蝉Karenia caelatata成虫消化道的形态学、组织学和超微结构研究,进一步了解蝉科(Cicadidae)代表种类的消化道形态和功能分化。【方法】利用光学显微镜和透射电子显微镜技术,对合哑蝉雄成虫消化道的整体形态以及食道、滤室(中肠前端及后端、马氏管基部、后肠基部)、滤室外中肠(锥形体、中肠环)、后肠(回肠、直肠)的一般形态和超微结构进行了详细观察,同时对滤室的组织结构进行了研究。【结果】结果表明,合哑蝉消化道由食道、滤室、滤室外中肠及后肠组成。食道狭长,被有上表皮和内表皮。中肠前端、中肠后端、马氏管基部以及后肠基部被一肌肉鞘包围形成滤室构造。组成中肠前端和后端的细胞基膜高度内褶,顶端的微绒毛发达。中肠后端分布许多线粒体和高电子密度的分泌颗粒。滤室外的中肠包括膨大的锥形体、中肠环。其中,锥形体由两种细胞组成;中肠环分为前、中、后3个不同的区段。前中肠细胞包含大量的分泌颗粒、线粒体、粗面内质网和溶酶体;中中肠细胞含有分泌颗粒;后中肠细胞包括许多低电子密度的分泌颗粒和滑面内质网。类铁蛋白颗粒零星分布于中肠环的前、中区段。组成锥形体和中肠环前端的细胞顶端微绒毛被丝状物质覆盖。后肠被有一层表皮。食道、中肠环中段、直肠细胞中含有微生物。【结论】本研究获得的合哑蝉消化道形态、组织结构和超微结构方面的信息为其功能分化研究提供了重要信息。同时,相关微生物的发现为进一步探讨共生菌与蝉总科昆虫的协同进化提供了信息。  相似文献   

3.
王玲丽  刘文哲 《植物学报》2005,22(5):584-589
通过HPLC测定了喜树(Camptotheca acuminata)不同器官及不同种源幼枝中喜树碱的含量。结果表明, 喜树碱含量在叶、种子和幼枝(幼叶和幼茎)中较高, 木质部中较少, 髓中最低。不同种源的幼枝中, 来自成都种源喜树的喜树碱含量最高。通过比较, 两年生喜树各器官中喜树碱含量普遍比一年生高, 幼枝中顶枝的喜树碱含量比侧枝高。  相似文献   

4.
文中通过对中药渣资源、处理和食用菌栽培的现状介绍,分析中药渣栽培食用菌的优势及产业现状。并以平菇为对象,简要阐述中药渣栽培食用菌技术路线,同时针对中药渣栽培食用菌产业中存在的问题进行反思,探讨解决问题的策略和方法。为进一步研究中药渣在食用菌生产上的应用提供依据,同时为中药渣合理处理提供方法。  相似文献   

5.
目的 对我国中医药卫生资源配置情况及变化趋势进行分析。方法 运用集聚度研究我国中医药卫生资源配置情况,分析不同区域中医药卫生资源集聚度的变化趋势。结果 我国中医药卫生资源配置的区域差异性大,且按地理和人口配置的卫生资源公平性有待进一步提高和优化。结论 提高中医药卫生资源可及性,满足不同区域人群的多样化中医药卫生服务需求。  相似文献   

6.
对白菜核雄性不育两用系可育花药和不育花药的ATPase做了定位分析。可育花药的花粉母细胞核中积累了大量的ATPase反应颗粒,而细胞质中ATPase反应颗粒较少,但在线粒体中特异地聚集了一些大的ATPase反应颗粒。减数分裂后,小孢子细胞质中ATPase反应颗粒明显增加。随着小孢子发育,其细胞质中ATPase反应颗粒逐渐减少,但在线粒体中又特异性地聚集了较多的AT-Pase反应颗粒。当花药发育到二胞花粉时期,花粉和绒毡层细胞中的ATPase反应颗粒已很少了。不育花药的花粉母细胞中呈现较多的ATPase,然而在线粒体中很少。异常四分体小孢子细胞质中虽然有较多的ATPase反应颗粒,但还是通过细胞质收缩和质壁分离方式退化。对可育花药的花粉母细胞线粒体中特异出现的簇状ATPase分布现象进行了分析,讨论了不育花药中花粉母细胞线粒体ATPase的异常与花粉败育的可能关系。  相似文献   

7.
营养膜无土栽培技术   总被引:1,自引:0,他引:1       下载免费PDF全文
营养膜技术(Nutrient Film Technique简称NFT)是国外广泛采用的一种特殊的无土栽培方法。它是将植物栽植在一个狭长的不透水的营养槽中,槽中有缓慢流动的营养液。植物根系的一部分浸没在营养液中,一部分露在空气中,植物从这种小环境中吸收水、营养物和氧气。  相似文献   

8.
小麦成熟胚囊卵细胞中存在较多围核分布的淀粉粒和少量散布的脂类颗粒;两个助细胞中积累很多脂类,未见有淀粉粒存在;中央细胞中存在中等量均匀分布的淀粉粒和脂类颗粒。受精时期,胚囊内各细胞中淀粉粒变化不大。精卵核融合时,卵细胞和中央细胞中的脂类分别存在一个积累高峰。合子与相应时期游离核胚乳中的脂类颗粒均较少。原胚初期,每个原胚细胞及胚乳原生质中均积累较多脂类。珠孔附近的内珠被细胞中脂类颗粒较多,并存在一个有规律的变化。在观察的所有发育时期的胚珠中,均未发现贮存蛋白质。胚珠中脂类的一系列变化可能与雌性细胞的营养、胚胎发育初期的养料及花粉管的定向生长等有关  相似文献   

9.
目的:近年来大肠中分化腺癌检出比例有所增高。本研究旨在探讨大肠中分化腺癌临床病理学及分子遗传学特征。方法:回顾过去30年1073例大肠癌的病理分型,比较其中328例高、中分化腺癌临床病理学特点。激光细胞学扫描技术,双荧光高分辨率微卫星不稳定性技术评价129例大肠癌遗传不稳定性特点,TP53、KRAS基因突变采用直接测序法检测。结果:由1979年始每10年为1组,至2008年计3组。中分化腺癌所占比例分别为37%、38%及55%。其中的328例大肠癌高、中分化腺癌病理学研究表明,中分化者较高分化者病期晚、浸润深、淋巴结转移率高、静脉侵袭阳性率高。对74例高分化腺癌与55例中分化腺癌的分子遗传学研究表明,高、中分化腺癌的DNA倍体与微卫星不稳定性情况无显著性差异,TP53与KRAS基因突变频率也无显著差异。但TP53的移码突变仅在高分化腺癌中检出(4例,P<0.05)。KRAS的颠换突变在高分化癌中检出5例(23%),在中分化癌中检出12例(57%),差异有显著性意义(P<0.05)。结论:高、中分化腺癌在临床病理学特征方面存在明显差异。大肠中分化腺癌较高分化腺癌生物学行为差,发现时病期较晚,治疗随访中需要引起足...  相似文献   

10.
赤链蛇不同组织Sox基因表达的RT-PCR分析   总被引:1,自引:0,他引:1  
采用RT-PCR技术,研究了赤链蛇不同组织Sox基因的表达。通过PCR产物直接克隆法和SSCP技术筛选阳性克隆,分析了雄性睾丸和雌性卵巢组织中的Sox基因序列。结果显示,在赤链蛇雌雄成体组织中,Sox基因在睾丸、卵巢、脑和脾组织中均有不同程度的表达,而在雌雄成体肌肉组织中均无表达,显示该基因表达有一定的组织特异性。序列分析显示睾丸组织中表达的是DRSox3,卵巢组织中表达的是DRSox22。在Sox家族中,Sox3表达于中枢神经系统和尿生殖嵴的发育过程中;Sox22则表达于多种组织和神经系统中,可横跨CNS和PNS的整个过程。此结果表明Sox基因不仅在性别决定中起作用,还可能在胚胎发育过程中担负重要功能。  相似文献   

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12.
Physical and immunogenic properties of reconstituted membranes designed for the presentation of tumour-associated antigens (TAA) to the immune system are described. Proteins and lipids of crude membranes of SL2 murine lymphosarcoma cells were partially solubilized with octylglucoside. Reconstituted membranes, consisting mainly of unilamellar vesicles with a diameter of 0.03–0.15 μm, were formed by detergent removal and were purified by floatation in a discontinuous sucrose gradient to remove non-lipid-bound protein. Subcutaneous immunization of syngeneic mice with reconstituted membranes or with purified reconstituted membranes induced protection against an intraperitoneal challenge with 103 viable SL2 cells. Reconstituted membranes were more immunogenic than crude membranes in immunoprotection experiments when compared on the basis of protein dose. Detergent removal was required to obtain an immunogenic presentation form of SL2 membrane antigens and to avoid toxicity associated with the detergent. Reconstitution of SL2 membranes in the presence of exogenous phospholipid slightly increased the fraction of protein that associated with the reconstituted membranes. However, the immunogenicity of the solubilized membrane TAA was not significantly affected by the presence of exogenous phospholipid. The reconstitution procedure described may be useful in identifying membrane factors required for the induction of immune responses against TAA. The versatility of the system may be employed to develop safe alternatives for whole-cell vaccines.  相似文献   

13.
A multifunctional calmodulin-dependent protein kinase (calmodulin kinase) was purified from the cytosol of rabbit skeletal muscle as a subunit of 58 kDa. A 58-kDa protein in sarcoplasmic reticulum (SR) and sarcolemma (SL) of rabbit skeletal muscle was endogenously phosphorylated in a calmodulin-dependent manner. The 58-kDa protein in SR and SL was considered to be identical to the subunit of cytosol calmodulin kinase on the basis of immunoreactivity, calmodulin binding, and autophosphorylation studies and on the patterns of protease-treated phosphopeptides. Calmodulin kinase showed broad substrate specificity and phosphorylated troponins I and T.  相似文献   

14.
To design anti-nucleocapsid drugs, it is useful to know the affinities the protein has for its natural substrates under physiological conditions. Dissociation equilibrium constants are reported for seven RNA stem-loops bound to the mature HIV-1 nucleocapsid protein, NCp7. The loops include SL1, SL2, SL3, and SL4 from the major packaging domain of genomic RNA. The binding assay is based on quenching the fluorescence of tryptophan-37 in the protein by G residues in the single-stranded loops. Tightly bound RNA molecules quench nearly all the fluorescence of freshly purified NCp7 in 0.2 M NaCl. In contrast, when the GGAG-tetraloop of tight-binding SL3 is replaced with UUCG or GAUA, quenching is almost nil, indicating very low affinity. Interpreting fluorescence titrations in terms of a rapidly equilibrating 1:1 complex explains nearly all of the experimental variance for the loops. Analyzed in this way, the highest affinities are for 20mer SL3 and 19mer SL2 hairpin constructs (K(d) = 28 +/- 3 and 23 +/- 2 nM, respectively). The 20mer stem-UUCG-loop and GAUA-loop constructs have <0.5% of the affinity for NCp7 relative to SL3. Affinities relative to SL3 for the other stem-loops are the following: 10% for a 16mer construct to model SL4, 30% for a 27mer model of the 9-residue apical loop of SL1, and 20% for a 23mer model of a 1 x 3 asymmetric internal loop in SL1. A 154mer construct that includes all four stem-loops binds tightly to NCp7, with the equivalent of three NCp7 molecules bound with high affinity per RNA; it is also possible that two strong sites and several weaker ones combine to give the appearance of three strong sites.  相似文献   

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摘要: 【目的】构建N-乙酰高丝氨酸内酯酶-木聚糖酶双酶活性表达毕氏酵母重组菌株,并对经纯化的重组蛋白SL2B 进行N-乙酰高丝氨酸内酯酶及木聚糖酶酶学性质的研究。【方法】利用PCR 拼接技术得到N-乙酰高丝氨酸内酯酶基因aiiA-B546 和木聚糖酶基因xynAS27cd 融合而成的基因Sl2b。构建重组表达载体pPIC9 / Sl2b 转化毕氏酵母,筛选得到同时具有木聚糖酶和N-乙酰高丝氨酸内酯酶活性的重组子,随后对经硫酸铵沉淀、分子筛纯化后得到的重组蛋白SL2B 进行N-乙酰高丝氨酸内酯酶及木聚糖酶  相似文献   

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Although it is well-accepted that the phosphatidylinositol signalling transduction pathway, producing inositol-1,4,5-P3 (InsP3) and inositol-1,3,4,5-P4 (InsP4) as second messengers, functions in heart muscle, virtually nothing is known about the roles of the higher inositol polyphosphates such as inositolhexakisphosphate (InsP6). This study demonstrates that InSP6 has the ability to bind intracellularly, with different binding characteristics, to different myocardial membranes. Binding to purified sarcoplasmic reticulum (SR) membranes, purified sarcolemmal (SL) membranes as well as to viable mitochondria were characterized. Binding to all these membranes display high as well as low affinity binding sites, with differing affinities. Kd values of binding to SR were 32 and 383 nM, to SL 61 and 1312 nM, while those of mitochondrial binding were 230 and 2200 nM respectively.InsP4 binding was also investigated and displayed the following characteristics: to SR, one low affinity binding site (Kd = 203 nM) and to SL, a high as well as a low affinity binding site with Kd values of 41 and 2075 nM respectively. Presence of InsP3, the second messenger for SR calcium release, at concentrations of 1 nM, elevated the binding of InsP4 to SR and SL by a mean of 30% and 20% respectively.Fractionation of SR and SL membranes on sucrose density gradients, after solubilization with CHAPS, indicated that InsP6 bound to two separate protein peaks in both these membranes, while InsP4 bound to only one. In SR membranes, InsP4 bound preferentially to a protein separating at high sucrose density while it bound to a protein separating at low sucrose density in SL membranes.  相似文献   

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20.
Somatolactin, a pituitary hormone belonging to the growth hormone/prolactin family, is produced in the intermediate lobe of teleost pituitary. To date, the functions of this new hormone and the target tissues are unknown. ASolea senegalensissomatolactin (ssSL) cDNA has previously been cloned and isolated. Here we have inserted this cDNA into a pET-3a plasmid in order to produce recombinant ssSL inE. coliBL21 (DE3) cells. The protein induced was isolated from inclusion bodies by a solubilization–renaturation procedure originally developed to generate native disulfide bonds, to get putative active proteins. The recombinant somatolactin was further purified to homogeneity by gel filtration on FPLC. The estimated molecular weight of 26 kDa by sodium dodecyl sulfate–polyacrylamide gel electrophoresis agrees well with the molecular mass calculated from the translated cDNA sequence and with native somatolactin (SL). The recombinant protein showed electrophoretic mobility identical to that of one of the native forms of SL secretedin vitroby cultured pituitaries from sole. Another native SL expressed inS. senegalensisrepresented a glycosylated modified hormone as shown byN-glycosidase treatment. Further, recombinant SL was recognized by an anti-native SL antibody and used to generate polyclonal sera reactive with the native pituitary hormone. To date, this represents the first recombinant SL protein isolated in sufficient quantities for biophysical and biochemical investigation and for studies on its physiological actions.  相似文献   

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