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1.
Following extraperiosteal injections of saline, serum, or whole blood, the synthesis of DNA in the cells of the osteogenic layer of the femora of mice was stimulated to approximately two-thirds of the level obtained by fracture of the femora. Irrespective of the material injected, the proliferative response of the cells in the periosteum was similar. These studies have shown that neither bone fracture nor direct disruption of the periosteum is necessary to induce periosteal cell proliferation since a single extraperiosteal injection of physiological saline induces DNA synthesis.  相似文献   

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3.
本文研究了注射含微囊藻毒素的微囊藻细胞抽提掖对小鼠血液以及免疫系统的亚慢性毒性作用。实验分为3个处理组和1个对照组(每组10只昆明小鼠,雌雄各半),采用腹腔注射的染毒方法对3个处理组进行暴露,剂量分别为2.4、4.8 和 9.6 μg microcystin-LR/kg body weigh,对照组注射等量的生理盐水,连续注射14d。实验结果表明,14d 染毒后,小鼠的肝体比和脾体比都明显增大(p < 0.05), 同时在9.6 μg/kg处理组,血清丙氨酸转移酶、天冬氨酸转移酶、乳酸脱氢酶和碱性磷酸酶活性与对照相比明显升高,但血清总蛋白、白蛋白和白蛋白/球蛋白比率下降。这些指标的变化说明,含微囊藻毒素的微囊藻细胞提取液对处理组小鼠肝脏造成了损伤,肝组织学观察也印证了这个结果,在处理组小鼠肝组织有明显的水样变性。另外,9.6 μg/kg处理组小鼠血液白细胞数量比对照组明显减少。组织细胞学观察发现,处理组小鼠脾脏也有明显的损伤。该实验结果说明,含微囊藻毒素的微囊藻细胞抽提液对小鼠的血液和免役系统都产生了一定程度的损伤。  相似文献   

4.
The ability of protaglandins E1 and E2 to stimulate the proliferation of haemopoietic stem cells (CFUs) was studied in vivo. PGE2, in a dose range of 10-4 to 10-1μg/g body weight and PGE1 in a dose range of 10-5 to 10-1μg/g body weight, produced a rapid cycling wave of CFUs. The increase in the number of CFUs in S phase was not followed by a rise in the femoral CFUs content, and except for a transient increase in femoral CFUc level, no increase in differentiation was found either. Therefore, it is proposed that haemopoiesis after PG-induced CFU stimulation is ineffective. PGE2 did not stimulate regeneration of CFUs in a perturbed state (after sublethal irradiation). All these findings support the idea that PGEs might represent potent stimulators of the haemopoietic stem cells acting in physiological doses. However, if acting concurrently with physiological control systems PGs lead to ineffective haemopoiesis (under normal conditions) or do not exert any measurable effect (after sublethal irradiation).  相似文献   

5.
1. The addition of blood serum displaces the optimum for agglutination of red blood cells in a salt-free medium to the reaction characteristic of flocculation of the serum euglobulin. 2. This effect is not due merely to a mechanical entanglement of the cells by the precipitating euglobulin, since at reactions at which the latter is soluble it protects the cells from the agglutination which occurs in its absence. 3. A combination of some sort appears therefore to take place between sheep cells and sheep, rabbit, and guinea pig serum euglobulin, and involves a condensation of the serum protein upon the surface of the red cell. 4. At the optimal point for agglutination of persensitized cells both mid- and end-piece of complement combine with the cells. 5. Agglutination is closely related to an optimal H ion concentration in the suspending fluid, and probably of the cell membrane, and not to a definite reaction in the interior of the cell.  相似文献   

6.
我们从体内及体外二个方面研究了棉酚对大鼠前列腺细胞的影响。在体内研究中,给成年SD大鼠口服棉酚对其前列腺作组织学观察;在体外研究中,将棉酚溶液直接加入培养系统中,对包括组织学结构、细胞生长速度、DNA合成状态及细胞分裂周期等多项指标进行分析。实验结果指出,在形态学上,经棉酚处理的大鼠前列腺的体积及重量均下降,与对照组有明显差异;二组前列腺的腺泡在组织学结构上也有明显不同:对照组前列腺的腺泡中充满突出的褶襞,由饱满的立柱形的上皮细胞构成这些褶襞及腺泡壁;而在实验组的腺泡中褶襞较少,构成褶襞及腺泡壁的为方形或扁方形的细胞。而腔内具有褶襞的腺泡总量实验组低于对照组约14%。根据体外实验的结果,可见随着棉酚浓度的增加,细胞增殖水平和DNA合成水平也相应下降,而呈剂量及时间的相关效应,其中10μg/ml的剂量能引起最大的抑制作用。根据对细胞分裂周期的分析,在棉酚组细胞进入S期的比例仅为全部细胞的31%,而对照组则为41%,这进一步说明了由于棉酚阻碍细胞进入S期从而抑制了细胞的增殖。  相似文献   

7.
客家人的红细胞血型分布   总被引:3,自引:0,他引:3  
对父母双方上溯三代均为客家人的广东梅县200名 (其中男89人,女111人) 健康学生进行了红细胞血型ABO,MNSs,Rh,Kidd,Duffy,Diego,Xg,Lewis及P等系统的分布调查。结果显示,客家人的基因频率S=0.0250,NS=0,pl=0.0917和Fyb=0.0300,都是汉族人群中最低的。其它基因频率为r=0.6632,p=0.1863,q=0.1505;m=0.5250,n=0.4750,MS=0.0250,Ms=0.5000,Ns=0.4750,s=0.9750;C=0.6575,D=1.0000,E=0.1515,CDe=0.6226,cDE=0.1200,cDe=0.2189,CDE=0.0389;JKa=0.4642,JKb=0.4881,JK=0.0477;Fya=0.9700;Dia=0.0202,Dib=0.9798;Xga=0.3633,Xg=0.6367;P2=0.9083。发现了国内第二例Jk(a-b-)表型,未发现MNS型,NS型,NSs型,CCDEE型,CcDEE型,Fy(a-)型和Rho(-)型。Le(a+b-)型29人,Le(a+b+)型2人,Le(a-b+)型67人,Le(a-b-)型102人。客家人与国内19个群体的遗传距离计算结果表明,与客家人遗传距离最近的是福建汉族、湖南苗族、贵州汉族及广西侗族,其次为河南汉族、黑龙江汉族、陕西汉族,福建畲族及上海汉族,而与云南白族、辽宁满族、甘肃汉族、广西瑶族、广西壮族、内蒙汉族及四川彝族的遗传距离较远。与客家人遗传距离最远的是湖南土家族、海南苗族及海南黎族。  相似文献   

8.
1. Unsensitized sheep cells suspended in sugar solutions are agglutinated by electrolytes whenever the potential is depressed to 6 millivolts or less, except in the case of MgCl2 or CaCl2. 2. With these salts no agglutination occurs although there is practically no potential. The presence of these salts prevents acid agglutination. This is presumably due to a decrease in the "cohesion" between the cells. 3. Cells which have been sensitized with specific antibody, ricin, colloidal stannic hydroxide, or paraffin oil, are agglutinated whenever the potential is decreased below about 12 millivolts. 4. The agglutination by electrolytes is therefore primarily due to a decrease in the potential whereas agglutination by immune serum, ricin, etc., is due primarily to an increase in the critical potential.  相似文献   

9.
采用不同浓度的抗坏血酸(50—800μmol/L)和硫酸亚铁(2.5—40μmol/L)系统生成以羟自由基为主的各种程度氧胁迫,使之作用于人肝癌细胞。本文所采用的不同程度的氧胁迫均能抑制癌细胞的生长。低水平氧胁迫可使肝癌细胞失去某些恶性特征,趋向分化,表现为细胞表面对Con-A的凝集力、甲胎蛋白含量、γ-谷氨酰转肽酶和酪氨酸-α-酮戊二酸转氨基酶活性都朝着分化方向变化,差异显著。分化后的细胞克隆形成能力显著降低。在分化过程中,出现一定量的凋亡细胞。随着氧胁迫程度的增高,凋亡细胞增多,表现为非贴壁细胞增多,细胞体积变小,染色质凝缩在核膜边缘,呈新月形,核碎裂,但质膜完整。细胞核中DNA降解成大约21.2kbp大小的大片段DNA。有望通过严格控制氧胁迫程度来减慢肝癌细胞增殖,促进分化和凋亡,使恶性细胞逆转成良性细胞。  相似文献   

10.
研究重点针对雨生红球藻绿色游动细胞的增殖培养阶段,分析了在利于细胞增殖的红光条件下,几种培养方式的调整对增殖过程和细胞活力的影响。结果显示:(1)在红光下,增殖平台期维持时间长,细胞活力稳定,细胞中性脂无累积,但进入平台期前,细胞中性脂有规律波动,进入平台期后相对稳定;通过更新率为20%的半连续培养,细胞数产出较批次培养提高57%;半连续培养中细胞呈现胁迫调节的时间较批次培养晚。随着培养时间增加,半连续培养下细胞营养盐吸收能力降低。(2)初始接种密度与细胞增殖速率及细胞光合活力呈负相关:初始密度低的细胞增殖速率较高,细胞光合作用活力高。(3)在培养过程中添加CO2时,最大密度均有提高,达6.0105 cells/mL,较无添加组提高54%;细胞分裂速率均有提高,但红光下较白光下增殖速率高(分别为0.223/d和0.198/d);添加CO2降低培养液pH,利于维持适宜增殖的pH环境。叶绿素荧光参数以及细胞粒径在红光和白光下有显著差异:红光下,Fv/Fm显著高于白光下;红光下补充CO2显著减小细胞粒径,而白光下粒径无显著变化。研究结果显示,在红光下,采用间断式半连续培养补充CO2培养绿色游动细胞,有利于提升细胞活力与产出。  相似文献   

11.
The cell proliferation of pre-implanted mouse embryos was investigated after development in vivo and in vitro. The studies were started at the pronuclear stage, 2 h post conception (p.c.) and continued until the hatching of blastocysts, 120–144 h p.c. The number of cell nuclei, the DNA content of each nucleus, the mitotic index and the labelling index were determined. From these data it was possible to calculate the length of the cell generation cycle and its various phases. With the exception of the first cell cycle the S-phase was constant. The G1- as well as the G2-phase varied in length during the different cell cycles. From 31–72 h p.c. the increase in cell number was exponential. After cultivation in vitro this increase was smaller than in vivo. At later periods the proliferation rate decreased with proceeding development. In late blastocysts most of the cells were in the G1-phase. The development of the embryos was somewhat faster in vivo than in vitro. But in principle conditions were comparable.  相似文献   

12.
激光能刺激造血细胞增殖,促使粒-巨噬细胞集落形成单位(GM—CFUc)增多。从人脐带血中分离制备的有核细胞,加入集落刺激因子(CSF)后,形成的GM—CFUc为18.6±12.6/10~4;如果加入的CSF是经激光照射后的细胞制成的,其GM—CFUc为40.5±20.2/10~4;若先用激光照射脐带血的有核细胞,在培养时加入的是未经激光处理细胞制成的CSF,也有增殖效应,GM—CFUc为36.5±18.5/10~4;如果脐带血有核细胞和制备CSF的细胞都用低能激光照射,就可以见到GM—CFUc明显地增多,其值为57.4±41.2/10~4是未经激光处理者的三倍。表明激光照射脐带血有核细胞及制备CSF的细胞均可使GM—CFUc增殖。  相似文献   

13.
离体培养的动物细胞增殖规律已有不少的报道,但是两栖类活体内细胞增殖过程如何,尚未见报道。本文运用SCD术,对泽蛙活体内骨髓细胞增殖动力学进行了较系统地观察,最后推算出Tc为12—24小时。  相似文献   

14.
本实验从新生大鼠嗅球中分离出嗅成鞘细胞,进行体外培养。运用RT-PCR方法检测甘丙肽及其受体在体外培养的嗅成鞘细胞中的表达;运用MTT法检测甘丙肽及其受体激动剂、拮抗剂对嗅成鞘细胞增殖的影响。结果显示:嗅成鞘细胞表达甘丙肽(GAL)及其受体GalR2,而不表达其他两种受体GalR1和GalR3;甘西肽及两种受体激动剂GAL1-11和GAL2-11能够明显地抑制体外培养的嗅成鞘细胞的增殖,这一效应可被非特异性甘丙肽受体拮抗剂M35所阻断。  相似文献   

15.
健康SD雄性大鼠,体重250—300g,麻醉、气管插管,用人工呼吸机经气袋供气,自发吸入氧浓度为9%的氧氮混合气,用SMUP-PC生物信号处理系统处理左心室功能。结果:(1)急性低氧经动脉血气分析可见PaO2下降(P<0.01),pH值升高(P<0.05),PaCO2稍下降(P>0.05),左心室功能各指标如LVP,HR,Vmp,±dp/dtmax,Vce40,Vmax,L0、等均下降;血液流变学指标如全血粘度(高、低切值及其还原值)升高,红细胞滤过指数(IF)升高;复氧后上述各指标恢复正常。(2)静脉注射心得安(0.5mg/Kg)后,使急性低氧诱发的左心室功能各指标更加明显下降,而血液流变学各值不再明显上升;静脉注射酚妥拉明(3mg/Kg)后,使急性低氧诱发的血液流变学各值上升不明显。(3)石炭酸破坏双侧颈动脉窦区后也可致低氧诱发的左心室功能各指标进一步下降,而血液流变学指标也不再明显上升。结果提示:急性低氧可引起左心室功能下降和全血粘度升高,红细胞变形能力降低,复氧后可恢复;交感神经活动及颈动脉窦区化学感受性反射可能对抗低氧诱发的左心室功能的下降,促进血粘度的升高。  相似文献   

16.
GENETIC VARIATION IN THE SHEEP RED BLOOD CELL   总被引:2,自引:0,他引:2  
1. There are 7 well-established red-cell antigen (blood group) loci. The R-O system has 3 phenotypes, R, O and i, identified by the ‘naturally occurring’ antibodies, anti-R and anti-O. The R and O substances are also present in soluble form in some body secretions. The expression of R and O is controlled by a dominant gene I, epistatic in effect, at an independent locus from that of R. The systems, A, C, M-L, B, D and X-2 are identified by means of ‘immune-type’ antibodies, and several of the loci have multiple alleles. An isoenzymic form of serum alkaline phosphatase is associated with the R-O system. The frequency for the genes at the various loci has been determined in a limited number of breeds. 2. Some sheep red cells have high K+ and low Na+ concentrations (HK type, or Key), others have low K+ and high Na+ concentrations (LK type or Kea). Two other rare forms exist; Key type which is HK but with lower than normal K+ values, and Kep type which has approximately equal Na+ and K+ concentrations. The red cells of foetuses and newborn lambs have high K+ levels irrespective of their potassium genotype. HK cells have 3–4 times greater (Na+-K+)-activated ATPase activity, a 3–4 times increased rate of active K+ transport and a larger number of ouabain-binding sites than LK cells. Antigen M is present on homozygous HK and heterozygous LK red cells, and antigen L is present on homozygous and heterozygous LK red cells. Sensitization of LK cells with anti-L stimulates active K+ transport and ATPase activity and exposes a larger number of ouabain-binding sites in these cells. Anti-M has no effect. The red cells of newborn lambs only show weak L and M antigen activity. It is postulated that L antigen inhibits cation transport in LK cells by masking the pump sites on the membrane. Immature red cells in LK-type sheep have a high rate of active K+ transport and yet have L antigen present. No satisfactory explanation for this has yet been advanced. There is no conclusive evidence that the potassium types have any significance from the point of view of adaptation or sheep breeding. The potassium-gene frequencies are known for a large number of breeds. 3. Two allelic genes, Hb4 and HbB control 3 haemoglobin phenotypes, A, AB, and B. Foetal haemoglobin (HbF) is present in foetuses and newborn lambs. Sheep with HbA also synthesize small amounts of another haemoglobin (HbC) and under conditions of severe anaemia, synthesis of HbC takes over from that of HbA. No change in HbB is observed in anaemia. A rare haemoglobin (HbD) has been found in 3 Yugoslavian sheep. Hbs A, B, C and F differ in their physicochemical properties; they share the same alpha chains but their non-alpha chains differ in a number of amino acids. HbD differs from HbA in one amino acid in the alpha chain. Certain genetic aspects are discussed. There is some evidence that sheep with HbA are less fertile than those with HbB. The gene frequencies for Hb are known for a large number of breeds. 4. Two isoenzymic forms of carbonic anhydrase are found in red-cell lysates and these are controlled by a pair of allelic autosomal genes, producing 3 phenotypes, CAF, CAFS and CAS. Only a few breeds have been studied but CAF is apparently quite rare. 5. An unidentified protein, designated ‘X’ is present in electrophoretic separations of haemolysates from some sheep. Its presence is dominant to its absence. Polymorphism at this locus is present in all breeds so far studied. 6. A deficiency of reduced glutathione (GSH) in red cells is found in some sheep and is inherited as an autosomal recessive disorder. Sheep with this deficiency have lower red-cell K+ and Naf concentrations than normal and it is suggested that the HK GSH-deficient sheep may be Ked type sheep. This deficiency has so far only been found with certainty in one breed of sheep. 7. In sheep twin chimeras, admixture of red-cell antigens, haemoglobin and ‘X’ protein types has been found. Various aspects of chimerism, which occurs only rarely in sheep, are discussed. 8. The significance of the genetic variation is discussed in the light of the physiology and immunology of the red cell and of the sheep itself.  相似文献   

17.
为探讨自由基对红细胞钙调机制的影响, 采用荧光标记的方法, 分别观察了健康人的红细胞在单纯Fenton 反应体系作用下和钙通道阻断剂+ Fenton 体系作用下胞内钙浓度的动态变化。发现:(1) 在Fenton 体系开始作用2 ~3 分钟后,红细胞内钙浓度才突然地急剧增加,此后便维持在一个明显低于胞外浓度的稳定水平;(2) 在Fenton 体系作用前后, 采用钙通道阻断剂镍可防止胞内钙的增加或使胞内钙浓度逐渐降至作用前水平。以上结果说明, 在Fenton 体系作用下, 红细胞仍保持对胞内异常高钙的清除能力,即自由基并不完全损害红细胞的钙调机制  相似文献   

18.
19.
本文用钙调素抑制剂——三氟拉嗪处理人胃癌MGC-803细胞,用免疫荧光细胞化学方法,放射免疫法和速流荧光分析等方法研究了钙调素对细胞增殖,环核苷酸代谢及微管组装,有丝分裂等细胞功能的调节作用。实验结果表明,TFP明显地抑制了人胃癌细胞的增殖,这种抑制增殖的作用,具有剂量和时间依赖关系,细胞群体中G_1期细胞增多,S期细胞下降,DNA合成明显地受到抑制。TFP处理的胃癌细胞仅在短时间内(5'-30')cAMP含量升高,cGMP浓度降低,cAMP/ ??cGMP比值比对照组高4.4倍,但此后环核苷酸含量又很快恢复到对照组水平。本实验还观察到TFP处理后的MGC-803细胞胞质铺展,细胞形态的改变与胞质微管的分布有密切联系,实验结果表明TFP加强了人胃癌细胞MTOC对微管的组装能力,使微管分布得到恢复,微管纤维呈放射状延伸到细胞边缘,充满胞浆,使细胞呈现出展平的多边形,趋向于正常上皮细胞形态的变化,本实验结果表明TFP抑制癌细胞增殖及使微管组装加强可能是通过对CaM活性的抑制作用。此结果有助于说明转化细胞内钙调素的变化,可能是与转化细胞增殖失控和胞质微管消退有关。  相似文献   

20.
1. No significant change with time (to 24 hours) in the cataphoretic velocity of certain mammalian red cells occurs when the cells are suspended in M/15 phosphate buffer at pH = 7.35. Neither successive washings nor standing effect a change. 2. In M/15 phosphate buffer at pH 7.35 ± 0.03 the following order of red cell velocity has been obtained. The numbers in parenthesis are µ per second per volt per centimeter. See PDF for Structure The order, though not the absolute values, was the same in buffered isotonic dextrose. Human and rabbit cells showed similar differences when both were studied simultaneously in the serum of either. Under these conditions, there is no apparent relationship between zoological Order and cataphoretic velocity. 3. Cholesterol and quartz adsorb gelatin from dilute solution in the phosphate buffer. Red cells, on the other hand, even after 24 hours contact with gelatin solution, retain their previous velocity. 4. Pregnant and non-pregnant white female humans have the same red cell cataphoretic velocity. (The cells were not agglutinated.) 5. In a series of severe anemias no significant change in cataphoretic velocity was in general apparent, although marked changes in the morphology of the red cells were present.  相似文献   

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