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951.
We previously found that the ability of peripheral blood mononuclear cells (PBM) of cancer patients to generate lymphokine-activated killer (LAK) cells became remarkably augmented after mitomycin C administration. On the basis of the clinical finding, we designed a treatment regimen comprised of 12 mg/m2 mitomycin C i. v. on day 1 and 700 U/m2 recombinant interleukin-2 (IL-2) i.v. every 12 h from day 4 through day 8. Of 25 patients with advanced carcinoma, 9 had a partial response and 3 had a minor response. Cytotoxic cell function, including natural killer activity, lymphokine-activated killer (LAK) activity, and the ability to generate LAK cells, and lymphocyte subsets in PBM was measured 1 day before and after either the first or second course of this therapy. The relationship between these parameters and the clinical antitumor response to this treatment was examined. Although the cytotoxic activities were significantly augmented after either the first or second treatment course, no positive correlation was observed between the changes in these cytotoxic activities and the clinical response to this therapy, when patients who either showed a partial response or whose disease remission was partial or minor were defined as responders. Further, phenotypic analysis showed a significant increase in CD2+, CD3+ CD4+ and CD4+Leu8 cells after the firs course, and CD25+ cells after either the first or second course of this treatment. The precentages of CD2+ and CD25+ cells were significantly elevated only in responders but not in nonresponders, suggesting the increase in these subsets was related to clinical response.  相似文献   
952.
本文就HHT、RA、WB_(852)对HL-60细胞的诱导分化作用及此过程中PKC活力在细胞胞浆部分及膜溶脱部分的变化进行研究。结果表明,在适当的用药浓度下,从细胞生长抑制情况、形态学观察及NBT还原能力测定判断,三种药物对HL-60细胞有明显的诱导分化作用。PKC活力分布变化的研究结果表明,用药组细胞胞浆部分酶活力有不同程度的下降,尤在用药早期(约6h以前)下降显著;而膜部分PKC活力则表现上升、或下降,或活力相差不大的结果。暗示在信息传递过程中起核心作用的PKC对不同的胞外刺激可能采取不同的应答方式。PKC的作用可能主要发生在信息传递的早期。  相似文献   
953.
本文采用系列凝集素柱层析法,并配合外切糖苷酶处理研究了在视黄酸(RA)作用1—5天过程中人肝癌细胞株SMMC-7721细胞表面N糖链结构的变化。结果表明,RA促进3~H-甘露糖(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,复杂型百分比上升,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C_2,C_(21)b三天线N糖链的合成减少。结果提示,N糖链结构的这些变化可能是RA诱导SMMC-7721细胞向正常方向分化的结果。  相似文献   
954.
In the present paper we investigated the effects of stem cell factor/mastocyte growth factor (SCF/MGF), leukemia inhibitory factor/differentiating inhibitory activity (LIF/DIA) (two growth factors known to affect primordial germ cell growth in vitro) and forskolin (FRSK) (an activator of adenylate cyclase in many cell types) alone or in combination on the survival and proliferation of primordial germ cells (PGCs) obtained from 8.5, 10.5, and 11.5 days post coitum (dpc) mouse embryos and cultured without pre-formed cell feeder layers. The results showed that both at 1 and 3 days of culture the addition of 100 ng/ml SCF, 20 μM FRSK, or in some instances 20 ng/ml LIF alone caused a significant increase of PGC number as compared with controls. The highest effects were obtained when SCF and/or LIF were used together with FRSK. Moreover, we found that FRSK elevated cAMP levels in purified 11.5 dpc PGCs and that this compound, but not SCF and LIF, stimulated PGC proliferation, as assessed by 5-bromo-2′-deoxyuridin (BrdU) incorporation. These results suggest a mechanism of combined action of cAMP with SCF and/or LIF in the control of proliferation of mouse PGCs in vitro. © 1993 Wiley-Liss, Inc.  相似文献   
955.
The effects of different epithelial cells, namely, hamster oviduct, sheep oviduct, and pig kidney epithelial cells (IBRS-2), on the viability, percentage of progressive motility (PPM), and acrosome reactions of ejaculated ram spermatozoa were investigated. Sperm aliquots were cultured on cells, cell-conditioned medium 199, or control medium 199. The PPM of unattached spermatozoa was estimated after 0, 3, 6, 9, 12, and 24 hr of incubation at 37°C under 5% CO2 in air. Viability and the occurrence of true acrosome reactions were assessed using a triple-stain technique. Spermatozoa started to attach within 1 hr of coculture with the hamster or sheep oviductal epithelial cell (OEC) monolayers, and these spermatozoa showed vigorous tail motion. No spermatozoa were found to attach to the IBRS-2 monolayer. The PPM of unattached spermatozoa cocultured with the various types of epithelial cell monolayers for 12 hr was significantly higher than that of spermatozoa incubated in conditioned media or medium 199 alone (54% in hamster OEC vs. 40% in conditioned; 68% in sheep OEC vs. 38% in conditioned; 36% in control medium). On the other hand, after 24 hr of incubation, there were no differences in the PPM of spermatozoa cocultured with epithelial cells or incubated in conditioned media. The percentages of cells undergoing a true acrosome reaction reached maximum values (P < 0.05) in spermatozoa incubated for 9 hr in the presence of hamster OEC (22.5%) or for 12 hr on sheep OEC (20.5%) monolayers. IBRS-2, a commercial nonreproductive cell type, had a positive influence on both PPM and sperm viability but no effect on the occurrence of the acrosome reaction. Interactions leading to the acrosome reaction were thus observed only when spermatozoa were cocultured with OEC monolayers. The values of PPM in unattached sperm cells seen after 12 hr of coculture with OEC or IBRS-2 were still at a high level (52–67%) for in vitro fertilization. The coculture with OECs provides an “in vitro” model to study the capacitation processes in a situation that may resemble that occurring in vivo. Moreover, the coculture with hamster OECs may provide a convenient and standardized in vitro system to study mechanisms underlying capacitation and the acrosome reaction. © 1993 Wiley-Liss, Inc.  相似文献   
956.
本研究用PAP法、胸腺细胞增殖法、脾细胞增殖法,分别检测16例体外HBV感染的骨髓单个核细胞与16例慢性乙型肝炎患者体内感染的骨髓单个核细胞(MNCs)中的HBcAg和白细胞介素-1(IL-1)、白细胞介素-2(IL-2)的诱生活性(以△cpm值表示)。结果显示,体外HBV感染组与体内HBV感染组骨髓MNCs中HBcAg检出率分别为50%和43.7%。本实验结果表明,HBV在体外感染骨髓MNCs,且与体内自然感染相符,但光镜下未观察到致细胞病变效应(CPE)。体外感染组与体内感染组IL-I和IL-2活性均较对照组明显下降(P<0.01)。且细胞中HBcAg检出阳性者较阴性者下降更为明显(P<0.01)。IL-1和IL-2诱生活性降低与HBV侵染免疫细胞及其在细胞内复制有密切关系,从而提示,IL-1和IL-2降低可能影响HBV的清除而引起慢性化过程。  相似文献   
957.
应用纤维连接素(Fn)、S—100蛋白、胶质纤维酸性蛋白(GFAP)、细胞角蛋白(CK)和神经特异性烯醇蛋白(NSE)5种抗体对63例正常人垂体前叶内滤泡星状细胞(FSC)进行了免疫细胞化学研究。结果表明:人FSC内26.9%S_(100)阳性,9.3%GFAP阳性,63.8%两者都为阳性。CK、NSE和Fn均为阳性。从而提示了FSC来自神经外胚层的原始细胞而非Rathke's囊上皮的残留。  相似文献   
958.
Using cytochemical method,microspectrophotometry and image analysis,effects of va-soactive intestinal peptide(VIP)on activities of succinic dehydrogenase(SDH)and alkalinephosphatase(ALP)in rat hepatoma cells were studied in vitro.The results showed that thehepatoma cell expressed potent positive reactions of SDH and ALP,the positive positionswere located at the cell membranes and/or cytoplasm.Having been treated with VIP,ALPdecreased obviously in activity(P<0. 01,compared with hepatoma cells untreated by VIP).The sites of ALP activty were chiefly located at the cell membranes,particularly at the cell-cell contacts.Cultured rat hepatoma cells had intensive SDH activity in their cytoplasm.Compared with untreated eclls,there was no marked difference in the intensity of SDH activ-ity in VIP-treated hepatoma cells(P>0.05).  相似文献   
959.
本文用高浓度的G418(800μg/ml)和低浓度的G418(200μg/ml)对包装细胞PLXSN/IL-2/PA317细胞进行40天的选择筛选培养,使其细胞呈稳定状态生长时,收集上清液转染NIH/3T3细胞,进行病毒滴度测定。试图在高选择标记的情况下筛选出高表达目的基因的包装细胞。实验结果表明:高、低浓度的G418对PLXSN/IL-2/PA317包装细胞的选择作用相同,即包装细胞的病毒滴度同选择标记物浓度无关。提示可用低浓度的G418来维持包装细胞的生命。  相似文献   
960.
山医群体近交系中国地鼠的红细胞、白细胞、网织红细胞、血红蛋白及血清蛋白量均与人类相近。血小板数高于人类,但低于小鼠。嗜中性与淋巴细胞的比值与人类相反而与小鼠近似。血清尿素氮及谷丙转氨酶高于人类生理值,低于SD大鼠。心率为658±102次/min,呼吸率20±30次/min。心电图除T波低平外,其余与人类相近。颈动脉血压为13.47±1.01/12.48±1.09kPa。染色体数为2n=22。以上各项在近交系地鼠和野生地鼠间未见明显差异。  相似文献   
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