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991.
对10头怀孕的中国荷斯坦奶牛和10头处于发情期的健康未孕同种奶牛的乳汁滤纸片,用放射免疫分析法测定乳汁中的孕酮含量,二者之间有极显著差异(P<005)。此方法,可为奶牛怀孕诊断提供1种简便、准确的新方法,并为监测卵巢功能活动及诊断、防治某些奶牛繁殖障碍疾病提供孕酮方面的依据。  相似文献   
992.
豇豆新品种穗丰8号的选育   总被引:2,自引:0,他引:2  
穗丰8号是从浙江省农家品种红嘴燕中采用系统选育育成的油青豇豆新品种。该品种中早熟,播种至初收春栽55~60d(天),夏秋栽49~50d(天);生长势强,分枝2条,主蔓第1荚着生节位第5节,荚长60cm、厚0.85~0.90cm,单荚质量25g,荚色油青,有光泽,荚条均匀,不露仁,无鼠尾,品质爽甜,耐贮运。抗逆性强,抗枯萎病,耐雨水,前期产量500kg·(667m~2)~(-1),总产量1 500kg·(667m~2)~(-1)左右。适宜华南地区种植。  相似文献   
993.
We have studied the ability of human peripheral blood lymphocytes (HuPBL)4 to interact with IgG from several animal species. Three functions or activities that are reported to depend on an interaction between complexed IgG and HuPBL receptors (R) for the Fc piece of IgG (FcγR) were compared: (1) antibody-dependent cell-mediated cytotoxicity (ADCC); (2) binding of heat-aggregated IgG (aggG); and (3) rosette formation with IgG-sensitized erythrocytes [RBC-A(γ)]. IgG (and IgM) antibodies to chicken erythrocytes (CRBC) were purified from the sera of the following species after injection with CRBC stroma: (1) horse (Ho); (2) goat (Go); (3) rabbit (Ra); and (4) guinea pig (Gp). Good IgG-agglutinating antibody titers were obtained from each injected species.

Using 51Cr-labeled CRBC targets and HuPBL effector cells, only Ra anti-CRBC IgG gave good ADCC at high dilutions. Ho and Go anti-CRBC (IgG) failed to give A C , and p anti-CRBC (IgG) gave approx. 30% of the level of kill as Ra. Ra Fab'2 fragments of IgG antibody failed to produce ADCC.

Treatment of HuPBL with Ra anti-lymphocyte serum (ALS) almost totally ablated ADCC, whereas HoALS failed to alter ADCC. Pretreatment of HuPBL with aggG showed that Ra or Hu aggG gave essentially equal inhibition of ADCC, Gp gave approx. 30% of the degree of inhibition as Hu and Ra, and Ho or Go aggG had essentially no effect of ADCC. These results confirmed the following order of ability of IgG to interact with HuPBL ADCC killer (K) cells: (Hu )Ra > Gp Ho, Go. The data suggest that Gp IgG interacts with only a subpopulation (≈ 30%) of HuPBL K cells.

The binding of aggG to total HuPBL failed to strictly correlate with the ADCC results or with the results of rosette formation between total HuPBL and CRBC-A(γ). The observations suggest that there is a heterogeneity of FcγR between K and non-K cell subpopulations of HuPBL both in terms of the type of complexed IgG they are able to bind, and in terms of the species of origin of the IgG. The data also support contentions that FcγR that bind RBCA(γ) complexes differ from those that bind aggG.  相似文献   

994.
AIM and METHODS: Chemotactic migration of peripheral blood mononuclear cell(PBMNC) of healthy blood donors(BD) and patients with blood stasis syndrome(BSS) across polycarbonate membrane(PCM) and human umbilical vein endothelial cell(HUVEC) monolayer, IL-8 produced by migrat PBMNC and effects of protocatechuic aldehyde(PCA) on the process mentioned above were investigated. RESULTS:1) The numbers of migrating PBMNC in group BSS was higher than that in group BD(P<0.01); 2) PCA inhibited PBMNC chemotactic migration in both groups; 3)Activity of IL-8 production PBMNC in group BSS was higher than that in group BD (P<0.05); 4)PCA inhibited activity of IL-8 produced by PBMNC. CONCLUSION:Ability of chemotactic migration and IL-8 production of PBMNC was much stronger in patient with blood stasis syndrome than those in healthy blood doner. PCA could significantly inhibit chemotactic migration of PBMNC and production of IL-8 by PBMNC.  相似文献   
995.
Bluetongue (BLU) virus is transmitted from infected to susceptible ruminants by hematophagous vector midges (Culicoides species). Cattle are important reservoir hosts of the virus because infection typically is asymptomatic and characterized by prolonged cell associated viremia, and because at least some species of insect vector preferentially feed on cattle. Interaction of BLU virus with the cell membrane of erythrocytes in infected cattle likely facilitates both prolonged viremia as well as infection of the insect vector. BLU disease is most common in sheep and some wildlife species. A variety of host, agent and environmental factors clearly can influence expression of disease in these species. The pathogenesis of BLU virus infection of cattle and sheep is remarkably similar, thus the basis for expression of disease in sheep but not cattle remains to be firmly established. Some difference in susceptibility of endothelial cells to infection in the two species is one potential explanation.

Ruminants develop a variety of antiviral responses after BLU virus infection. Antibodies to outer capsid protein VP2 are responsible for virus neutralization, and confer resistance to reinfection with the homologous serotype of BLU virus. Antibodies to epitopes on proteins which are common to all viruses of the BLU serogroup form the basis of current diagnostic serologic tests. Cell mediated responses have been incompletely characterized, in part because BLU virus replicates within dividing lymphocytes and virus-mediated cytolysis inhibits in vitro blastogenesis. Immunological competence of ruminants to BLU virus arises prior to midgestation, and suggestions that persistent immune tolerant BLU virus infection occurs after in utero exposure of cattle have not been substantiated and are not consistent with recent findings.  相似文献   

996.
文章提出了基于机器视觉的测量方式,主要测量工件的面积、周长和边长等数据。测量采用固定装置,标定采用传统标定法。硬件系统采用了USB接口的工业相机。软件主要对图像进行了预处理,预处理为图像的切割、灰度化、滤波。  相似文献   
997.
八爪除草机构的设计与实验-基于虚拟样机技术   总被引:2,自引:0,他引:2  
为了实现田间株间精确机械除草,设计了一种八爪式智能除草机构,并重点研究了在实现不同株距株间除草时所需的前进速度和转速,进行了ADAMS动力学仿真实验和土槽中的物理样机实验.仿真和实验结果表明:该结构的设计能使工作爪端的割刀伸入株间进行除草,仿真实验中的割刀中心轨迹能够有效完成株间除草,并在样机试验中得到了验证.  相似文献   
998.
大豆异黄酮受多基因控制,采用传统育种方法提高大豆异黄酮含量比较困难。我们之前的研究中表明,CHS8基因在异黄酮生物合成过程中发挥着重要作用,但CHS8基因过量表达并不能显著提高异黄酮含量。本研究利用Microarray技术,检测了高异黄酮品种RCAT Angra (RCAT)和低异黄酮品种Harovinton (HVNT)的18 362基因在种子发育过程中表达水平的变化以及大豆种子中异黄酮累积的趋势,利用RT-PCR证实CHS8和IFS2分别是CHSs和IFSs基因家族中的主要基因;证实CHS8是类苯基丙醇主路径中的主基因,并发现异黄酮支路中的IFS2基因在RCAT和HVNT品种中表达差异亦达到显著水平。进一步利用发根农杆菌转化系统,在大豆上分别过量表达CHS8、IFS2和CHS8+IFS2,前两者异黄酮含量较对照分别提高65.9%和34.4%,但增幅未达显著水平;而后者则提高了82.3%,增幅达显著水平(P<0.0001),因而证实大豆中异黄酮的积累由CHS8和IFS2基因共同决定。  相似文献   
999.
AIM: To investigate the role of Th17 cells in the patients with cervical cancer.METHODS: We measured the peripheral levels of Th17 cells and CD3+CD8-IL-21+ T cells in 37 cervical cancer (CC) patients, 25 cervical intraepithelial neoplasia (CIN) patients and 18 healthy controls by flow cytometry. The percentages of Th17 cells and CD3+CD8-IL-21+ T cells in total CD4+ cells were calculated.RESULTS: Compared with controls, the patients with CC or CIN had higher proportions of Th17 cells (all P<0.01) and CD3+CD8-IL-21+ T cells (all P<0.05). Notably, in CC patients, the increased percentages of Th17 cells and CD3+CD8-IL-21+ T cells were independently associated with the clinical stage(all P<0.05), lymph node metastasis (P<0.01,P<0.05) and vasoinvasion (all P<0.01), while the elevated percentage of CD3+CD8-IL-21+ T cells was also associated with the tumor size(P<0.01). Furthermore, the percentage of Th17 cells was positively correlated with that of CD3+CD8-IL-21+ T cells in healthy controls and CC patients, but not in CIN patients.CONCLUSION: Our results indicates a possible role of Th17 cells in CC patients correlated with CD3+CD8-IL-21+T cells, and the elevated percentage of circulating Th17 cells may be involved in the development and progression of cervical cancer.  相似文献   
1000.
为了促进南瓜单倍体育种,通过介绍雌配子形成过程,综述了近年来南瓜属蔬菜未授粉子房(或胚珠)离体培养概况,并对离体雌核培养的影响因素进行分析,对再生植株倍型鉴定和单倍体加倍方法进行阐述,最后探讨其当前存在的问题和应用前景。  相似文献   
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