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81.
The production of dendritic cells (DC) from haemopoietic progenitors maintained in long term stroma-dependent cultures (LTC) of spleen or bone marrow (BM) occurs independently of added granulocyte/macrophage colony stimulating factor (GM-CSF). The possibility that cultures depend on endogenous GM-CSF produced in low levels was tested by attempting to generate LTC from spleen and BM of GM-CSF-/- mice. Multiple cultures from GM-CSF-/- and wild type mice were established and compared for cell production. GM-CSF-/- LTC developed more slowly, but by 16 weeks produced cells resembling DC in numbers comparable to wild type cultures. LTC maintained distinct populations of small and large cells, the latter resembling DC. Cells collected from GM-CSF-/- LTC were capable antigen presenting cells (APC) for T cell stimulation and morphologically resembled DC. Large cells expressed the CD11b, CD11c, CD86, 33D1 and Dec-205 markers of DC. Addition of GM-CSF to GM-CSF-/- LTC increased the proportion of large, mature DC present in culture. Stromal cells from GM-CSF-/- LTC could support the differentiation of DC from early progenitors maintained in LTC without addition of GM-CSF. However, GM-CSF is not a critical factor in the in vitro generation of DC from progenitors. It can, however, substitute for stromal cells in increasing the survival of mature DC. 相似文献
82.
原发性肝细胞癌中5种细胞周期蛋白的表达及其临床意义 总被引:4,自引:0,他引:4
目的探讨原发性肝细胞癌中5种细胞周期蛋白(cyclin)的表达及其与肝癌细胞的增殖状态、侵袭转移和乙型肝炎病毒(HBV)感染的相关性。方法应用Instrumedics公司生产的组织芯片制作仪,将273例原发性肝癌组织、144例癌旁肝组织和10例尸检非肝病死亡肝组织制成组织芯片,取样针直径2.0am,采用免疫组织化学方法分别检测了cyclin A、cyclin B、cyclin D1、cyclin D3及cyclin E在肝癌、癌旁肝及尸检肝组织的表达率,并分析了肝癌、癌旁肝组织中HBV感染与这5种cyclin表达间的相关性。结果共获得3个肝癌组织芯片蜡块,分别含136、143和148个位点。在273例肝癌组织标本中5种cyclin的阳性表达率分别为cyclin A 52.7%、cyclin B 45.4%、cyclin D1 35.9%、cyclin D3 44.3%和cyclin E 23.1%;在144例癌旁肝组织中分别为8.3%、5.6%、4.9%、6.3%和1.4%;10例尸检肝组织除1例cyclin D1阳性外,其余均为阴性。5种cyclin在肝癌组织中的阳性表达率均显著高于癌旁肝组织(P<0.01);组织学分级为Ⅱ、Ⅲ级的肝癌组织5种cyclin的表达高于Ⅰ级(P<0.05);除cyclinA外,伴有门静脉癌栓组的阳性率高于无癌栓组(P<0.01);HBV感染与cyclin的表达无明显相关性(P>0.05)。结论各个cyclin在肝癌细胞中呈不同程度的高表达,使癌细胞周期缩短,处于细胞增殖活跃状态,并有利于肝癌细胞的侵袭转移;未发现与HBV感染有关。 相似文献
83.
Genistein对体外培养的Parkinson病模型大鼠多巴胺能神经元及突触素的影响 总被引:3,自引:0,他引:3
为了探讨genistein(GST)对离体培养的Parkinson病模型大鼠多巴胺能神经元以及突触素的影响,取孕14~16d SD大鼠胚胎中脑腹侧部,常规体外培养。将培养的中脑腹侧细胞分为四组:正常对照组、雌二醇(E2)+MPP+组、GST+MPP+组、MPP+组。进行四甲基偶氮唑盐(MTT)法测定细胞活力和代谢状态。采用TH和突触素(synaptophysin,SYN)免疫荧光组织化学染色技术,观察各组TH阳性神经元的生长状况以及突触数量的变化。结果显示:与正常对照组、E2+MPP+组以及GST+MPP+组相比,MPP+组TH阳性神经元数量少,SYN免疫活性产物表达亦减少,细胞活力差。而E2+MPP+组、GST+MPP+组中上述指标与正常对照组相比,差异无统计学意义。以上结果提示Genistein对体外培养的多巴胺能神经元具有类似雌激素样的神经保护作用。 相似文献
84.
Catt SL; Sakkas D; Bizzaro D; Bianchi PG; Maxwell WM; Evans G 《Molecular human reproduction》1997,3(9):821-825
Controlling the sex of offspring by the separation of X and Y
chromosome-bearing spermatozoa using flow cytometry has been reported as a
clinical technique aiding prevention of X-linked diseases. Although this
technique has resulted in several hundred normal births in animals and at
least one human birth, there is still concern over its genetic safety due
to the involvement of two potentially mutagenic agents: UV light and the
fluorochrome dye, Hoechst 33342 (H33342). Human spermatozoa, particularly
those considered abnormal, may be more likely to suffer DNA damage
following exposure to mutagenic agents, compared with other mammalian
species. The stability of normal fresh and decondensed human spermatozoa
were examined after exposure to a range of levels of UV and H33342
staining, using an assay that detects endogenous nicks in the DNA of
spermatozoa. The stability of abnormal and normal, fresh and frozen-thawed
human spermatozoa was examined following UV laser, H33342 staining and flow
cytometry treatments utilizing the same assay. There was an increase in the
presence of endogenous nicks when spermatozoa were decondensed compared
with fresh spermatozoa. There was no increase in the incidence of nicks in
any group of spermatozoa after UV and fluorochrome exposure compared with
controls without exposure.
相似文献
85.
用反卷积法校正X线图像散射的方法 总被引:3,自引:0,他引:3
在数字X线摄影中,散射造成了图像对比度的下降,在影像增器-电视链成像系统中来自病人的散射和来自探测器系统的眩光更是恶化图像质量的主要原因。为了提高数字X线图像的质量,我们利用高斯曲线近似散射点扩展函数,并在一特定的系统上用实验的方法确定了散射量ρ和散射分布参数σ, 相似文献
86.
Patterns of contrast enhancement of benign and malignant hepatic neoplasms during bolus dynamic and delayed CT 总被引:7,自引:0,他引:7
Bolus dynamic and delayed computed tomographic (CT) scans of the liver were evaluated in 43 patients with 54 hepatic hemangiomas and 111 patients with primary or secondary malignant hepatic neoplasms. Twelve patterns of contrast enhancement were recognized during the bolus dynamic phase and delayed scanning. A "typical" CT pattern for hemangiomas (present in 29 of 54 hemangiomas [53.7%]) was established: (a) diminished attenuation prior to intravenous contrast medium administration (excluding lesions arising in a liver with diffuse fatty infiltration), (b) peripheral contrast enhancement during the bolus dynamic phase, and (c) complete isodense fill-in on delayed scan images. Using these criteria, we distinguished hemangiomas from malignant neoplasms in most patients. Only one of 63 (1.6%) malignant neoplasms manifested these typical CT criteria of hemangioma. There is an 86% chance that a lesion with the typical CT appearance of hemangioma is actually a hemangioma, even when found in a patient with a known nonhepatic primary neoplasm. 相似文献
87.
目的 了解长沙地区无偿献血人群隐匿性乙型肝炎病毒感染(occult hepatitis B virus infection,OBI)流行情况,探讨HBV基因型分布特征和S区氨基酸突变的情况。方法 对长沙地区检测结果为HBsAg-/HBV DNA+的无偿献血血液样本进行HBV血清标志物检测,对其中的OBI样本进行HBV病毒载量检测和S区基因扩增,分析血清学标志物抗HBs与病毒载量检出与否的关系,并对扩增产物进行HBV基因分型和突变位点分析。结果 2019年1月—2020年1月长沙地区173 893份无偿献血标本共确认58例OBI样本,OBI流行率为0.033%;共发现7种血清学模式,抗HBc单独阳性最多,占38.98%,所有样本中抗HBc阳性率为89.83%;16例样本能检测出病毒载量,其中14例样本浓度小于100 IU/ml;抗HBs阳性组和阴性组间的病毒载量检出率无统计学差异;75.0%(12/16)样本扩增出S区序列,基因型均为B型,均发生突变,其中11例的HBsAg抗原决定簇及周边主要亲水区域(major hydrophilic region, MHR)发生氨基酸突变。结论 长沙地区无偿献血者中的OBI感染率在全国属于偏低水平;HBV基因型主要是B型,MHR区的氨基酸突变可能是造成OBI的原因,突变有本地特点。 相似文献
88.
目的探索老年患者日间手术全程质量管理模式。方法通过医院病历系统采集2015年-2020年应用老年患者日间手术全程质量管理模式前后患者信息,进行对比分析。结果老年患者应用日间手术全程质量管理模式后,≥65岁老年患者日间手术人数逐年上升,占比从13.52%上升至18.62%,差异有统计学意义(χ2=6.450,P=0.011);日间手术住院时间>5 d的比例从0.72%下降至0.50%,差异有统计学意义(χ2=338.088,P<0.001);不良事件发生率从3.77‰下降至1.56‰,差异有统计学意义(χ2=5.156,P=0.023),其中严重不良事件发生率从2.08‰下降至0.35‰,差异有统计学意义(χ2=7.019,P=0.008)。结论应用日间手术全程质量管理模式能够有效提高老年患者日间手术的安全性,值得借鉴与推广。 相似文献
89.
目的 研究广东省中老年人群睡眠状况与高血压患病的关联性,为高血压防控“关口前移”提供科学依据。方法 采用“2018年广东省慢性病及危险因素监测数据”,按照多阶段整群随机抽样方法,纳入5 636名≥45岁中老年人为研究对象。运用SAS 9.4软件进行Rao-Scott 检验和基于复杂抽样构建logistic回归模型分析睡眠状况与高血压患病的关系。运用R 4.0.5软件绘制限制性立方样条曲线分析睡眠时间与高血压患病风险的量效关系。结果 广东省中老年人高血压患病率是37.93%,平均睡眠时间是(7.36±1.61)h; 其中男性平均睡眠时间多于女性,而女性睡眠问题比例显著高于男性。经多因素回归模型控制后,睡眠时间不足或过多(OR=1.280,95%CI:1.128~1.452; OR=1.300,95%CI:1.038~1.627)、入睡困难(OR=1.286,95%CI:1.018~1.626)、中间觉醒≥2次(OR=1.239,95%CI:1.036~1.483)和服用安眠药(OR=1.567,95%CI:1.086~2.261)均使高血压患病风险升高。结论 广东省中老年人群的睡眠时间不足或过多、入睡困难、中间觉醒≥2次和服用安眠药均与高血压患病显著正相关,应对该特征的人群进行干预,旨在降低高血压的患病率。 相似文献
90.
Ryan Gage Martin Girling-Butcher Ester Joe Moira Smith Cliona Ni Mhurchu Christina McKerchar Viliami Puloka Rachael McLean Louise Signal 《Nutrients》2021,13(1)
Snacking is a common eating behaviour, but there is little objective data about children’s snacking. We aimed to determine the frequency and context of children’s snacking (n = 158; mean age = 12.6 years) by ethnicity, gender, socioeconomic deprivation and body mass index (BMI) children. Participants wore wearable cameras that passively captured images of their surroundings every seven seconds. Images (n = 739,162) were coded for snacking episodes, defined as eating occasions in between main meals. Contextual factors analysed included: snacking location, food source, timing, social contact and screen use. Rates of total, discretionary (not recommended for consumption) and healthful (recommended for consumption) snacking were calculated using negative binomial regression. On average, children consumed 8.2 (95%CI 7.4, 9.1) snacks per day, of which 5.2 (95%CI 4.6, 5.9) were discretionary foods/beverages. Children consumed more discretionary snacks than healthful snacks in each setting and at all times, including 15.0× more discretionary snacks in public spaces and 2.4× more discretionary snacks in schools. Most snacks (68.9%) were sourced from home. Girls consumed more total, discretionary and healthful snacks than boys, and Māori and Pacific consumed fewer healthful snacks than New Zealand (NZ) Europeans. Results show that children snack frequently, and that most snacking involves discretionary food items. Our findings suggest targeting home buying behaviour and environmental changes to support healthy snacking choices. 相似文献