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21.
肺癌组织培养液和病人血清对自身T细胞集落形成能力的影响 总被引:2,自引:1,他引:2
本文观察了10例肺癌病人围术期的肺癌组织、正常肺组织培养液和血清对自身外周血T细胞集落形成能力的影响,并以14例正常人的血清作为对照。结果显示:肺癌人病在去肿瘤负荷前T细胞集落产率为160.73±124.02/10~5,故低于正常人的397.81±133.89/10~5(P<0.001),也低于去肿瘤负荷后的(P<0.001)306.53±79.86/10~5(P<0.001)。术前病人的血清对T细胞集落的抑制率为46.97±21.42%,术后则下降至27.63±23.25%(P<0.01)。加进肺癌组织培养液时,病人的T细胞集落产率为224.83±104.05/10~5,正常肺组织培养液则为323.12±125.27/10~5(P<0.001),肺癌组织培养液和病人血清两者对T细胞集落产率的抑制性呈正相关关系(r=0.817,P<0.005)。本研究结果认为,肺癌组织能产生细胞免疫抑制物质进入血循环,导致病人T细胞集落形成能力明显下降。手术根治性切除肺癌组织,能有效地解除T细胞集落形成能力受抑制的情况。 相似文献
22.
小鼠巨细胞病毒模型的建立 总被引:3,自引:0,他引:3
目的为了探讨巨细胞病毒的致病机理。方法4周龄Balb/C小鼠腹腔内接种小鼠巨细胞病毒(MCMV)。结果导致小鼠急性感染期体重下降,生长迟缓,唾液腺肿胀以至于死亡。唾液腺中检出高滴度感染性病毒(2.0×105PFU/ml)。在小鼠3T3/Swisalbino细胞单层上形成的空斑清晰,易判断计数、镜检组织切片可见脑神经原细胞胞浆内包涵体。结论小鼠巨细胞病毒模型的建立为抗-CMV有效药物的筛选以及对CMV感染的预防、治疗提供了资料。 相似文献
23.
Bone marrow cells from young and old mice (C3H/HeMs) were transplanted into irradiated syngeneic recipients. The growth rates of spleen colonies in both groups were compared by measuring the mean volume of colonies. Growth rates in spleen colonies derived from bone marrow cells of 462-day-old mice (Y-R) were higher than those from 917-day-old mice (O-R). Bone marrow cells from 62-day-old mice and those from 642-day-old mice were injected into 112-day-old irradiated (950 rad) recipients and after 400 days were killed. The bone marrow cells were assayed for spleen colony-forming units (CFU-S) and injected into irradiated secondary recipients, 50-55 days of age (Y-M-R and O-M-R). The cellular age at testing was 462 and 1042 days, respectively. The growth rates of colonies from young mice (Y-M-R) and from old ones (O-M-R) were similar in contrast to the first experiment in which the younger CFU-S produced more rapidly growing colonies. These studies clearly show that CFU-S from 462-day-old mice produce larger splenic colonies than CFU-S from 686- or 917-day-old mice. However, spleen colonies formed by CFU-S with cellular ages of 462 days (62 days + 400 days in vivo) and 1042 (642 days + 400 days in vivo) are not significantly different, suggesting that "in vivo incubation" has removed some of the proliferative defect of the 642-day-old CFU-S. 相似文献
24.
We have determined cutaneous DTH reactions to SK-SD and PPD and peripheral blood lymphocyte profiles in a group of asbestos workers in two consecutive surveys. It was found that asbestosis and, to a lesser extent, the presence of ANA are significantly correlated with the lack of response to the above antigens. 83% of asbestos workers when tested at a 4 year interval fell into the same two categories of responsiveness (lack of response or response at least to one antigen).The asbestosis cases had lower total lymphocyte count as well as proportions and absolute number of E-RFC as compared to asbestos workers without asbestosis and/or ANA. Furthermore, the latter group showed the lower percentages and absolute number of E-RFC than the matched controls. The presence of ANA is also correlated with lower proportions of E-RFC. However, this is related at least in part to asbestosis. 相似文献
25.
Labeling of cells with ferumoxides-protamine sulfate complexes does not inhibit function or differentiation capacity of hematopoietic or mesenchymal stem cells 总被引:12,自引:0,他引:12
Arbab AS Yocum GT Rad AM Khakoo AY Fellowes V Read EJ Frank JA 《NMR in biomedicine》2005,18(8):553-559
Two FDA-approved agents, ferumoxides (Feridex), a suspension of superparamagnetic iron oxide (SPIO) nanoparticles and protamine sulfate, a drug used to reverse heparin anticoagulation, can be complexed and used to label cells magnetically ex vivo. Labeling stem cells with ferumoxides-protamine sulfate (FePro) complexes allows for non-invasive monitoring by MRI. However, in order for stem cell trials or therapies to be effective, this labeling technique must not inhibit the ability of cells to differentiate. In this study, we examined the effect of FePro labeling on stem cell differentiation. Viability, phenotypic expression and differential capacity of FePro labeled CD34 + hematopoietic stem cells (HSC) and mesenchymal stem cells (MSC) were compared with unlabeled control cells. Colony-forming unit (CFU) assays showed that the capacity to differentiate was equivalent for labeled and unlabeled HSC. Furthermore, labeling did not alter expression of surface phenotypic markers (CD34, CD31, CXCR4, CD20, CD3 and CD14) on HSC, as measured by flow cytometry. SDF-1-induced HSC migration and HSC differentiation to dendritic cells were also unaffected by FePro labeling. Both FePro-labeled and unlabeled MSC were cultured in chondrogenesis-inducing conditions. Alcian blue staining for proteoglycans revealed similar chondrogenic differentiation for both FePro-labeled and unlabeled cells. Furthermore, collagen X proteins, indicators of cartilage formation, were detected at similar levels in both labeled and unlabeled cell pellets. Prussian blue staining confirmed that cells in labeled pellets contained iron oxide, whereas cells in unlabeled pellets did not. It is concluded that FePro labeling does not alter the function or differentiation capacity of HSC and MSC. These data increase confidence that MRI studies of FePro-labeled HSC or MSC will provide an accurate representation of in vivo trafficking of unlabeled cells. 相似文献
26.
Kikuchi T Ichimiya S Kojima T Crisa L Koshiba S Tonooka A Kondo N Van Der Saag PT Yokoyama S Sato N 《International immunology》2004,16(6):831-841
In this study, we investigated the localization and functional significance of p53 tumor suppressor-like molecules, p63 and p73, in human thymic epithelial cells (TECs). Immunohistochemical studies showed particular distribution profiles of p63 and p73 in thymic epithelium, in which cortical TECs preferentially expressed p63 in their nuclei whereas subcapsular and medullary TECs expressed both p63 and p73 in their nuclei. The wide distribution of p63 in TECs was further suggested by studies using TECs of primary culture. In vitro studies using two human TEC lines demonstrated that p63 was capable of up-regulating intercellular adhesion molecule-1 (ICAM-1) and enhancing the production of IL-6 and IL-8. Moreover, in vitro studies also indicated that p73, but not p63, had the capacity to induce granulocyte macrophage colony stimulating factor (GM-CSF) and granulocyte colony stimulating factor (G-CSF) in the TEC lines. These findings suggest that p63 would regulate the cell adhesive property through ICAM-1/LFA-1 interaction and the production of IL-6 and IL-8, probably in all TEC subtypes. p73 in subcapslar and medullary TECs was suggested to play a role in the regulation of the production of GM-CSF and G-CSF, which might stimulate other stromal cells such as dendritic cells, macrophages and endothelial cells around these regions. 相似文献
27.
As yeast colonies ceased growth, cells at the edge of these colonies transited from the cell division cycle into meiosis at high efficiency. This transition occurred remarkably synchronously and only at late stages of colony maturation. The transition occurred on medium containing acetate or low concentrations of glucose, but not on medium containing high glucose. The repression by high glucose was overcome when IME1 was overexpressed from a plasmid. Experiments with different growth media imply that meiosis in colonies is triggered by changes in the nutrient environment as colonies mature. HAP2 is required to sporulate in any carbon source, whereas GRR1 is required for glucose repression of sporulation. CLN3 is required to repress meiosis in colonies but not in liquid cultures, indicating that the regulators that mediate the transition to meiosis in colonies are not identical to the regulators that mediate this transition in liquid cultures. 相似文献
28.
目的 :探讨草酸钙结石的形成机理和影响因素。方法 :根据微溶电解质动力学原理 ,利用草酸与氯化钙作用形成草酸钙的性质 ,加入其它尿液中常见组分 ,测定草酸钙诱导期与过饱和溶液浓度的关系 ,并分析结石的显微结构。结果 :草酸钙的诱导期与溶液过饱和浓度呈反比关系 ,且不同干扰因素对草酸钙的过饱和比影响也不同。结论 :钙和草酸是草酸钙形成的必要条件 ;溶液的过饱和是草酸钙成核的基础 ;基质对草酸钙起胶结作用 ;氯化钠、氯化铵、氯化镁能促进草酸钙的形成 ,而氯化铁、尿素、甘氨酸能抑制草酸钙的沉淀。 相似文献
29.
《Seminars in Fetal & Neonatal Medicine》2022,27(1):101322
Neonatal diseases such as hypoxic ischemic encephalopathy, diseases of prematurity and congenital disorders carry increased morbidity and mortality. Despite technological advancements, their incidence remains largely unabated. Stem cell (SC) interventions are novel therapies in the neonatal world. In pre-clinical models of neonatal diseases, SC applications have shown encouraging results. SC sources vary, with the bone marrow being the most utilized. However, the ability to harvest bone marrow SCs from neonates is limited. Placental-tissue derived SCs (PTSCs), provide an alternative and highly attractive source. Human placentas, the cornerstone of fetal survival, are abundant with such cells. Comparing to adult pools, PTSCs exhibit increased potency, decreased immunogenicity and stronger anti-inflammatory effects. Several types of PTSCs have been identified, with mesenchymal stem cells being the most utilized population. This review will focus on PTSCs and their pre-clinical and clinical applications in neonatology. 相似文献
30.