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961.
An Adenocarcinoma cell line (Breast-M) and an Epstein-Barr virus (EBV)-infected B-cell line (Hairy-BM) were established from breast tumor tissue. The Hairy-BM was CD20+, CD25 (Tac)+ and surface immunoglobulin (sIg)+. Hairy-BM suppressed the in vitro proliferation of Breast-M in a time and a dose-dependent manner. The suppression was also found in 5 different human tumor targets showing tumor-Hairy-BM binding, but not; in 2 murine tumor targets showing no significant tumor-Hairy-BM binding. Lytic activity of Hairy-BM was found only against Breast-M.Abbreviations sIg Surface immunoglobulin - CTL Cytotoxic T-cells - NK Natural killer - IL2 Interleukin 2 - LAK Lymphokine activated killer - CSN Culture supernatant - MTT 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoolium bromide - PCR Polymerase chain reaction - TIL Tumor-infiltrating lymphocytes - HCL Hairy cell leukemia - TNF Tumor necrosis factor  相似文献   
962.
Summary A B-cell line was established from the liver of an 11-yr-old boy with Epstein-Barr virus (EBV)-associated post-transplant lymphoproliferative disease (PTLD). The cells were morphologically heterogenous, CD10 (CALLA) negative, and expressed several B-cell antigens, including CD23, in a manner reminiscent of lymphoblastoid cell lines (LCLs) reported in the literature. However, the cells also showed expression of the CD77 antigen, carried a 14q32+ chromosomal anomaly, and showed IgM-kappa immunoglobulin isotype restriction immediately after their outgrowth in culture. These latter properties are typically associated with Burkitt’s lymphoma cell lines rather than LCLs. Aberrant expression of the L60 antigen on these B-cells was found as additional evidence of altered growth regulation in these cells. EBV infection was demonstrated by the abundant expression of EBNA-2 and LMP viral antigens in culture. The cell line described should be useful in planning in vitro experiments designed to understand the factors that modulate the growth of PTLD in vivo.  相似文献   
963.
Patterns of tree species distribution and their structural-functional features were studied along an altitudinal gradient in the Indian Central Himalaya. The forest vegetation falls within three formation types: low to mid-montane sclerophyllous, broad-leaved forests; mid-montane deciduous forests; and high-montane mixed stunted forests. Deciduous tree species formed a considerable (49%) portion of the high altitude forests between 1500–3300 m. The upper limit of forests ranges from 3000 to 3300 m, and three taxa are commonly found at tree line: an evergreen, needle-leaved gymnosperm (Abies pindrow Spach.), an evergreen, broad-leaved sclerophyllous oak (Quercus semecarpifolia Sm.), and a deciduous, broad-leaved birch (Betula utilis Don).The high altitude forests differed from the low altitude forests of Central Himalaya in their greater proportion of microphanerophytes. Vernal flowering is common at this elevation in Central Himalaya. In general, in their elevational distribution and structural-functional attributes, these high altitude forests are similar to other forests of cool temperate zones in Himalaya.  相似文献   
964.
本文采用系列凝集素柱层析法,并配合外切精苷酶研究了在双丁酰环磷酸腺苷(dB-cAMP)作用1~5天过程中人肝癌细胞株SMMC-7721细胞表面N-糖链类型及复杂型糖链天线数的变化。结果表明,dB-cAMP促进3H—Man参入细胞表面N-糖链,使高甘露糖型N-糖链的百分比下降,并促进二天线N-糖链的生物合成。使多天线特别是四天线和C2C2C6三天线N-糖链的百分比减少.结果提示,N-糖链结构的这些变化可能是dB-cAMP诱导SMMC-7721细胞向正常方向分化的结果。  相似文献   
965.
应用低温同步法与秋水酰胺处理,对人体乳腺癌细胞系Bcap-37和MCF-7的中期及早中期细胞进行G-显带分析。研究表明,Bcap-37细胞染色体众数为63,可识别其结构的标记染色体17条;MCF-7细胞染色体众数为56,可识别其结构的标记染色体13条。结合文献报道以及本研究结果显示,乳腺癌中最常涉及到第1、3、5、7、11、13和17号染色体结构及数目的异常,染色体断裂点1p11(1q11)、1p13、3p21、3q11、5q11、6q13、6q23、7q22、11p13和11p15也经常涉及;它们可能与癌相关基因的激活和抗癌基因的丢失有关,从而在乳腺癌发生发展中起一定作用。  相似文献   
966.
聂道泰  周广和 《遗传学报》1994,21(6):468-473
利用多个生化标记系统对一个抗小麦黄矮病新种质(HG295)进行了分析鉴定,胚乳水溶蛋白等电聚焦表明,在pH8.0-10.2范围内,中5有3条在其小麦亲本南大2419、克强中匀不存在的克异带,其中只有和经2条在HG295中得到表达。在HG295中,2DS控制的那条水溶蛋白带发生了的缺失,HG295中2DS的缺失在Per-5与Est-6电泳分析中进一步得到确证,Est-7酶谱表明,中5与HG295均表  相似文献   
967.
Some studies indicated a relationship between modern, fast-growing, lean-meat-producing hybrid pigs and the occurrence of tail-biting, one of the major issues of conventional pig husbandry. Therefore, this study investigated the effects of different local, traditional sire breeds on the behaviour and performance of rearing pigs. Between December 2019 and November 2020, a total of 1 561 piglets were weaned from hybrid sows (Bundes Hybrid Zucht Programm (BHZP) Landrace × BHZP Large White) that were paired with either Swabian-Hall (SH), Bentheim Black Pied (BB) or BHZP-Piétrain (Pi) boars. Tails of the piglets were left intact (43.5%) or docked (56.5%), and male piglets were castrated. Piglets were conventionally reared on fully slatted plastic flooring in mixed-sex groups. Starting one day after weaning, skin lesions were scored once per pig, and tail lesions and losses were scored weekly until the end of rearing. The average daily gain was documented for the suckling and rearing period. The activity behaviour of eight focal pens was analysed using video recordings. Differences between modern and traditional breeds were found in this study for so-called aggressive and non-aggressive biting pronounced by skin and tail lesions and tail losses. Significantly fewer BB pigs had severe skin lesions on the front body than SH or Pi pigs (P < 0.05). Additionally, piglets that were classified as light (<5.6 kg) at weaning showed skin lesion scores of 0 more often than piglets that were classified with a medium (≥5.6–≤8.3 kg) or heavy (>8.3 kg) weaning weight (P < 0.05). In the first half of the rearing period, significantly more BB pigs were assessed as having no tail lesions and tail losses than SH and Pi pigs (P < 0.01). However, these differences disappeared in the second half of rearing. Either docked or undocked Pi pigs had significantly higher average daily gains than SH and BB pigs (P < 0.05). The activity of the focal pens was not influenced by the sire breed or tail lesion class, which might be due to the limited sample size of eight pens. To conclude, the use of the traditional sire breed BB has the potential to reduce injurious behaviour in the offspring. However, adjustments to the housing and feeding should be taken to further reduce the incidence of tail lesions and losses and to enhance performance.  相似文献   
968.
摘要 目的:探讨与分析手足口病(HFMD)合并脑炎患儿外周血T淋巴细胞亚群、血清VCAM-1及CRP的表达水平及其检测价值。方法:2017年4月到2020年10月选择在本院诊治的手足口病合并脑炎患儿42例作为合并组,同期选择手足口病不合并脑炎患儿68例作为对照组,检测两组外周血T淋巴细胞亚群、血清血管细胞粘附分子-1(VCAM-)及C-反应蛋白(CRP)表达水平,并判断检测价值与进行相关性分析。结果:合并组的CD4+、CD8+T淋巴细胞相对比例都明显少于对照组(P<0.05)。合并组的血清VCAM-1及CRP含量明显高于对照组(P<0.05)。在80例患儿中,Spearsman分析显示CD4+、CD8+T淋巴细胞相对比例和血清VCAM-1、CRP含量都与手足口病合并脑炎的发生存在相关性(P<0.05)。二分类Logistic回归分析显示CD4+、CD8+T淋巴细胞相对比例和血清VCAM-1、CRP含量都为导致手足口病合并脑炎发生的重要因素(P<0.05)。结论:手足口病合并脑炎患儿多伴随有外周血T淋巴细胞亚群异常与血清VCAM-1、CRP的高表达,CD4+、CD8+T淋巴细胞相对比例、血清VCAM-1、CRP含量都为导致手足口病合并脑炎发生的重要因素。  相似文献   
969.
摘要 目的:对比内侧开放楔形胫骨高位截骨术(OWHTO)、人工全膝关节置换术(TKA)治疗膝关节内翻畸形的疗效及对术后下肢力线和创伤应激的影响。方法:回顾性分析贵州医科大学附属医院2020年3月~2022年1月期间接收的膝关节内翻畸形患者临床资料,共计75例。根据手术方案的不同分为OWHTO组(n=40)和TKA组(n=35)。对比两组围术期指标、视觉疼痛模拟评分(VAS)评分、美国特种外科医院(HSS)膝关节评分、膝关节活动度(ROM)、应激指标和术后下肢力线改变情况。结果:OWHTO组手术时间、切口长度短于TKA组,术中出血量、住院费用少于TKA组(P<0.05)。OWHTO组术后1个月VAS评分低于TKA组,ROM、HSS膝关节评分高于对照组(P<0.05)。OWHTO组术后3 d、术后7 d血清皮质醇(COR)、促肾上腺皮质激素(ACTH)水平低于TKA组(P<0.05)。两组术后6个月股胫角(FTA)下降,髋-膝-踝角(HKA)升高(P<0.05)。两组术后6个月FTA、HKA组间对比差异不显著(P>0.05)。两组并发症发生率组间对比未见差异(P>0.05)。结论:OWHTO、TKA这两种治疗方案治疗膝关节内翻畸形,具有相当的疗效,均可有效改善下肢力线,但OWHTO的创伤小、应激程度轻。  相似文献   
970.
Summary A new cell line was developed from 3-d-old embryonated eggs of the cabbage looper,Trichoplusia ni, and has been designated IPLB-TN-R2. It contains a variety of morphological cell types, including myoblastlike, neuroblastlike, and epithelial-like cells. Chromosome analysis revealed typical lepidopteran chromosomes. Isozyme characterization showed patterns similar to two other cabbage looper cell lines (TN-368 and IAL-TND1) in the case of five enzymes but differed from these two lines for two other enzymes. Virus infectivity tests revealed the line is highly susceptible toAutographa californica nuclear polyhedrosis virus, but no cytopathology was observed after inoculation with several other lepidopteran viruses.  相似文献   
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