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1.
本文对不同海拔地区白唇鹿的呼吸、心率、体温、红细胞数、白细胞数、血红蛋白含量、红细胞形态等12项生理指标进行了测定.发现生活在高海拔地区的白唇鹿,其呼吸、心率、红细胞数、血红蛋白含量,中性和酸性白细胞均高于低海拔地区的白唇鹿,而红细胞压积和红细胞平均体积却与海拔高度呈负相关。体温在不同海拔高度大致相同,电镜下,红细胞形态呈双面凹陷的轮胎状,直径4.368±0.192μm。  相似文献   

2.
以洋葱为材料,研究1%TritonX-100抽提非骨架蛋白时间、细胞环境温度和紫外线照射活细胞对洋葱细胞骨架形态观察效果的影响。结果表明:1%TritonX-100抽提非骨架蛋白25min观察效果较好,细胞处在20℃和4℃环境下骨架清晰完整,呈网络状分布;-18℃、50℃及紫外线照射60min处理均会造成细胞骨架不同程度的解聚,影响细胞骨架的观察。  相似文献   

3.
本研究以苯胺(AN)为单体,含磺酸基的水性界面活性剂N,N-二(2-羟乙基)-2-氨基乙磺酸(BES)为掺杂剂,过硫酸铵(APS)为引发剂,利用化学氧化合成法制备含BES掺杂的结构型导电聚苯胺(简称PANI-BES).产物以四点探针测量导电度发现,经由导电度测试,AN∶APS∶BES=1∶1∶0.6为最佳,并经穿透式电子显微镜(TEM)测试表明其产物大部分为中空状的,场发射型扫描式电子显微镜(FE-SEM)测试得知不同摩尔比的部分产物呈现中空状,且具有球状、树枝状、片状等型态,并利用傅立叶转换红外线光谱仪(FTIR)进一步确认以BES掺杂聚苯胺的化学结构,利用这些不同的方法分别探讨PANI-BES的界面形态、表面形态、结晶特性等相关性质.  相似文献   

4.
以木棉、香蒲绒、竹浆、木浆、苇浆纤维素粉末为研究对象,研究了其形态结构、回潮率及热性能.研究发现,纤维素粉末断面呈不规则状,表面有不同程度的损伤,但保留了其相应纤维的形态特征;木棉、香蒲绒、竹浆、木浆、苇浆纤维素粉末回潮率分别为11.3%,10.5%,9.2%,11.6%和9.5%;通过热失重(TG)分析发现,5种纤维素粉末起始降解温度均高于250℃,比较而言,香蒲绒纤维素粉末热稳定性较差,竹浆纤维素粉末热稳定性较好.研究结果为纤维素粉末应用提供理论依据.  相似文献   

5.
低温诱导对组培川贝母胚状体成苗的影响   总被引:7,自引:1,他引:6  
组培川贝母(Fritillaria Cirrhosa D.Don)的胚状体经低温处理不同的时间,随后转入无激素的MS培养基中培养,发现低温处理40d的胚状体成苗率最高.对过氧化物酶的活性及其电泳图谱的研究发现,在低温处理及随后的培养过程中,过氧化物酶的活性、表达量及谱带数(特别是B区酶带)已发生明显的变化.C区酶带的出现,是川贝母低温处理诱导胚状体成苗的一个重要因素.  相似文献   

6.
采用柠檬酸钠还原H2PtCl6制备得到浅黄棕色负电铂纳米颗粒.研究发现,该纳米颗粒使α,β,γ,δ-四(N-甲基-3-吡啶基)卟啉(TMPyP-3)发生J-型聚集,使其特征的Soret带和Q带吸收降低,荧光猝灭、散射信号增强,圆二色光谱及暗场成像发生变化.当铂纳米粒子浓度发生变化时,TMPyP-3聚集程度不同,其光学信号的变化强度也有差异,为进一步阐明卟啉类物质聚集体形成的过程及形态奠定了基础.  相似文献   

7.
中国野生牡丹花粉形态的研究   总被引:4,自引:0,他引:4  
通过扫描电镜观察了芍药科(Paeoniaceae)芍药属(Paeonia)牡丹组(Sect.Moutan DC.)9个野生种23个居群的花粉形态.该组花粉多为长球形,少数近球形和超长球形,具三拟孔沟,大小为22.7~46.4 μm×13.6~29.9 μm,外壁纹饰形态多样,可分为穴状、网状、粗网状、条纹-网状、皱波-网状、皱波状.分析结果表明:花粉形态与植物的外部形态特征有一定关系,同一种野生牡丹生长在不同的环境中,其花粉形态也不同.因此,花粉分析对牡丹组种的区分有一定的参考价值,但要合理揭示其系统发育意义,仍需进行更全面深入的研究.  相似文献   

8.
本文报告万宁县两个区苗族居民185户共522人地中海贫血症(以下简称地贫)的调查结果。共检出不同类型地贫患者126人,分属81户。地贫人数占受检人数24.1%。地贫患者户数占受检户数43.8%。检出 HbA_2。含量在3.5%以上者67人,占受检数12.8%,他们分属35户。有一个村 HbA_2含量在3.5%以上人数高达26.7%,HbA_2增高的67例中有5例伴有 HbF 带,HbA_2含量在3.5%以下有 HbF 带者19例。在受人数中发现有 NHP 带深染,经联苯胺染色证明此位置有成份为 HbC_o-nstant Spring 慢泳带者29例,占5.5%,同时发现β°-地贫纯合子1例。HbH 病3例。α-地贫_1(又称标准型α-地贫)9例。该处为地贫发生率较高及类型较多地区。海南岛苗族居民的地贫发病情况资料较少,1986年初对万宁县苗族进行了调查如下:  相似文献   

9.
马元铅锌矿床是扬子板块周缘发现的大型铅锌矿床之一,该矿床类型为密西西比河谷型(MVT)铅锌矿床。角砾状白云岩为主要的富矿岩系,可见脉状、透镜体状矿脉,矿体中富含大量的固体或者焦沥青,沥青为灰黑色,呈球颗状、细(网)脉状、液滴状或不规则状,与铅锌矿石密切共生/伴生在一起。沥青来源为上伏地层下寒武统郭家坝组黑色炭质板岩,构造活动对有机质运移产生重要作用。不同高程和不同形态沥青的反射率大致相同,沥青反射率3.10%~4.71%,平均值为3.93%,有机质达到过成熟阶段,最大古地温(T_(max))261~311℃,平均值288℃。  相似文献   

10.
以洋葱表皮细胞为材料,探究其经卡诺氏液固定后进行细胞骨架制片观察时,1%Triton X-100抽提非骨架蛋白的最佳时间,并研究洋葱不同表皮细胞及经不同理化因素处理的材料,经卡诺氏液固定后进行细胞骨架制片的步骤及制片效果。结果表明:经卡诺氏液固定后,1%Triton X-100抽提非骨架蛋白内表皮30min较佳,外表皮25min较佳;不同成熟度的鳞片叶细胞骨架形态及稳定性有差异;经紫外线、温度、秋水仙素处理后增加固定步骤再制片对制片观察结果基本无影响。  相似文献   

11.
遗传球形红细胞增多症红细胞膜力学特性研究   总被引:1,自引:0,他引:1  
彩和微管吸吮实验技术并结合十二烷基硫酸钠-聚丙烯酰胺凝胶电泳等生化方法研究遗传球形红细胞增多症红细胞膜粘弹性特及膜骨架蛋白的变化。结果表明:HS红细胞膜的弹性模量和正常对照组比较无明显差异而粘性系数显著高于正常值,细胞粘滞性增大型汽轮发电机组轴系的变形能力降低;  相似文献   

12.
V Bennett  P J Stenbuck 《Nature》1979,280(5722):468-473
Ankyrin, the membrane attachment protein for human erythrocyte spectrin, is tightly linked in a 1:1 molar ratio with band 3 in detergent extracts of spectrin-depleted membranes. Ankyrin-linked band 3, which represents 10--15% of the total band 3, spans the membrane, and is nearly identical to the major band 3 by peptide analysis. Spectrin binds to solubilised ankyrin-linked band 3, but not to free band 3. A portion of band 3 remains firmly associated with detergent-extracted cytoskeletal proteins. It is concluded that a fraction of band 3 is attached to the erythrocyte cytoskeleton through association with ankyrin, which in turn is bound to spectrin.  相似文献   

13.
V Bennett 《Nature》1979,281(5732):597-599
Ankyrin is a polypeptide of molecular weight (MW) 200,000 which is tightly bound to the cytoplasmic surface of the human erythrocyte membrane and has been identified as the high-affinity membrane attachment protein for spectrin. This protein has also been shown to be associated with band 3 (ref. 4), the major transmembrane protein which links a cytoplasmic structural protein to an integral membrane protein. A water-soluble, 72,000-MW, proteolytic fragment of ankyrin has been purified which retains the ability to bind to spectrin, and competitively inhibits reassociation of spectrin with membranes. Monospecific antibodies directed against this fragment have been prepared and demonstrated to cross-react only with ankyrin among the erythrocyte membrane proteins. The present study reports the use of these antibodies to develop a radioimmunoassay capable of detecting femtomolar quantities of ankyrin, and demonstrates the presence of small but significant amounts of immunoreactivity in a variety of types of cells and tissues.  相似文献   

14.
15.
Band 3 and glucose transport protein (GluT1) are two kinds of important proteins in the human erythrocyte membranes. Bis(sulfosuccinimidyl)suberate (BS3), an impermeable cross-linker of band 3, inhibited NO2 transport, showing that anion exchange is affected by the association state of band 3 in the intact erythrocyte membranes. At the same time, the rates of glucose transport of both exit and entry declined. The amount of monomers of band 3 was decreased after treatment of the erythrocytes with BS3, but there was no change in GluT1 according to the SDS-PAGE patterns. This demonstrates that band 3 and GluT1 would be linkaged together in the erythrocyte membranes for the requirement of rapid and cooperative performance of physiological functions of the membrane proteins.  相似文献   

16.
R A Anderson  V T Marchesi 《Nature》1985,318(6043):295-298
Many of the physical properties of the erythrocyte membrane appear to depend on the membrane skeleton, which is attached to the membrane through associations with transmembrane proteins. A membrane skeletal protein, protein 4.1, is pivotal in the assembly of the membrane skeleton because of its ability to promote associations between spectrin and actin. Protein 4.1 also binds to the membrane through at least two sites: a high-affinity site on the glycophorins and a site of lower affinity associated with band 3 (ref. 11). The glycophorin-protein 4.1 association has been proposed to be involved in maintenance of cell shape. Here we show that the association between glycophorin and protein 4.1 is regulated by a polyphosphoinositide cofactor. This observation suggests a mechanism which may explain the recently reported dependence of red cell shape on the level of polyphosphoinositides in the membrane.  相似文献   

17.
To explore the possibility of absorption of lanthanides via digestive duct and their effects on the membrane structure and permeability of erythrocytes, the fine structure of erythrocyte membrane from Wistar rats, fed for 70 days of daily administrationper os with 20 mg CeCl3/kg weight, was imaged by means of atomic force microscopy and FT-IR deconvolution spectra. The results show that, although the erythrocytes maintain the intact shape, the change of secondary structure, aggregation and crosslinking of the protein particles of membrane surface and the enlarged lipid regions lead to the domain structure formation. This structure might be responsible for the increasing permeability of erythrocyte membrane.  相似文献   

18.
Y Jinbu  S Sato  M Nakao 《Nature》1984,307(5949):376-378
The shape of the human erythrocyte depends on intracellular ATP content and echinocytic erythrocyte ghosts obtained in the presence of Mg-ATP acquire a diskocytic shape after incubation at 37 degrees C; however, agreement is lacking about the molecular basis of the shape changes. The suggestion that phosphorylation of cytoskeletal structures underlying the membrane is involved has been disputed and alternative explanations based on lipid bilayer theory and metabolism of phospholipid have been proposed. Recently, we re-examined the effect of ATP on the shape of ghosts and found that it consists of two distinct steps. We have, therefore, now examined the effect of physiological concentrations of Ca2+ and ATP on the cytoskeleton of the erythrocyte membrane directly using Triton-treated ghosts which had lost this permeability barrier. Our findings suggest that a noncovalent effect of ATP on the cytoskeleton is a prerequisite for shape change.  相似文献   

19.
To explore the possibility of absorption of lanthanides via digestive duct and their effects on the membrane structure and permeability of erythrocytes,the fine structure of erythrocyte membrane from Wistar rats,fed for 70 days of daily administration per os with 20 mg CeCl3/kg weight,was imaged by means of atomic force microscopy and FT-IR deconvolution spectra.The results show that,although the erythrocytes maintain the intact shape,the change of secondary structure,aggregation and crosslinking of the protein particles of membrane surface and the enlarged lipid regions lead to the domain structure formation.This structure might be responsible for the increasing permeability of erythrocyte membrane.  相似文献   

20.
Modulation of spectrin-actin assembly by erythrocyte adducin   总被引:3,自引:0,他引:3  
K Gardner  V Bennett 《Nature》1987,328(6128):359-362
The spectrin-based membrane skeleton, an assembly of proteins tightly associated with the plasma membrane, determines the shape and mechanical properties of erythrocytes. Spectrin, the most abundant component of this assembly, is an elongated and flexible molecule that, with potentiation by protein 4.1, is cross-linked at its ends by short actin filaments to form a lattice beneath the membrane. These and other proteins stabilize the plasma membrane, organize integral membrane proteins and maintain specialized regions of the cell surface. A membrane-skeleton-associated calmodulin-binding protein of erythrocytes is a major substrate for Ca2+- and phospholipid-dependent protein kinase C (ref. 5), and thus is a target for Ca2+ by two regulatory pathways. Here we demonstrate that this protein, called adducin: (1) binds tightly in vitro to spectrin-actin complexes but with much less affinity either to spectrin or to actin alone; (2) promotes assembly of additional spectrin molecules onto actin filaments; and (3) is inhibited in its ability to induce the binding of additional spectrin molecules to actin by micromolar concentrations of calmodulin and Ca2+. Adducin may be involved in the action of Ca2+ on erythrocyte membrane skeleton and in the assembly of spectrin-actin complexes.  相似文献   

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