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991.
应用激光电泳技术对MA737小鼠乳腺癌细胞膜表面电荷特性的研究 总被引:2,自引:0,他引:2
本工作应用激光多普勒电泳技术对MA737小鼠乳腺癌细胞膜表面电荷特性及高温(42.5℃)对癌细胞的热效应进行了深入的研究。结果发现,MA737癌细胞的电泳迁移率(EPM)明显高于相应正常细胞的EPM(约20%),表明癌细胞表面负电荷增高;实验发现唾液酸可能是MA737癌细胞膜表主要负电基团的来源之一。研究还发现,MA737癌细胞的热敏性比相应的正常细胞强,随高温受热时间的延长,癌细胞的EPM呈下降趋势。 相似文献
992.
993.
目的:评估特瑞普利单抗联合舒尼替尼治疗晚期肾细胞癌的疗效与安全性。方法:回顾性分析2020年1月—2022年3月海军军医大学第二附属医院接受特瑞普利单抗联合舒尼替尼治疗的25例晚期肾癌患者临床资料,其中男21例,女4例,中位年龄为59 (33~80)岁。25例患者病理类型均为透明细胞癌,其中2例为TFE3融合基因相关肾癌,1例部分肉瘤样变,25例患者均发生局部进展或远处转移。评价其生存获益和相关不良反应发生情况。结果:中位随访时间11.0(2.5~24)个月,25例患者均可评价疗效,总体人群ORR 36.0%,DCR 84.0%,9例患者部分缓解,12例患者病情稳定,4例患者疾病进展,中位PFS 12.7个月(95%置信区间:10.7~14.7),中位OS尚未达到。治疗总体不良反应发生率为88.0%,常见不良反应包括皮疹、腹泻、手足皮肤反应、高血压等,90%的不良反应为1~2级。 相似文献
994.
995.
W. Thoenes H. J. Rumpelt S. Störkel 《Journal of molecular medicine (Berlin, Germany)》1990,68(22):1102-1111
Summary After a controversial phase of nomenclature (including — among others — the terms hypernephroma and hypernephroid carcinoma) a cytomorphologically defined subtyping of renal cell tumours (adenomas, carcinomas, oncocytomas) is offered, based on new electron microscopical and histochemical observations. These data are in part supported by cytogenetical findings reported in the literature. Phenotypical/histogenetical relations to different parts or cell types, respectively, of the nephron-collecting duct system could be demonstrated. Chromophobe cell carcinoma and oncocytoma exhibit features of the intercalated cells.
Herrn Prof. Dr. Dr. h.c. Adalbert Bohle gewidmet 相似文献
996.
Nika Adham Laurence A. Borden Lee E. Schechter Eric L. Gustafson Tamara L. Cochran Pierrre J.-J. Vaysse Richard L. Weinshank Theresa A. Branchek 《Naunyn-Schmiedeberg's archives of pharmacology》1993,348(6):566-575
We recently described the cloning of a fifth member of the 5-hydroxytryptamine (5-HT)1 (serotonin1) receptor class that inhibits adenylyl cyclase, namely the human 5-HT1F receptor (Adham et al. 1993 a). In the present study we have examined in greater detail the functional coupling of the 5-HT1F receptor in two different cell lines, NIH-3T3 and LM(tk–) fibroblasts (receptor densities of 1.7 and 4.4 pmol/mg protein, respectively). The maximal inhibitory response elicited by 5-HT was significantly greater in NIH-3T3 as compared to LM(tk–) cells, whereas the EC50 values were comparable.To investigate the relationship between receptor occupancy and inhibition of cAMP accumulation mediated by 5-HT1F receptors in NIH-3T3 cells (and hence the degree of receptor reserve), we used the irreversible receptor antagonist N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ). The half-maximal response required only about 10% receptor occupancy, consistent with a receptor reserve of 90% (88±2.1%, n = 4) for 5-HT-induced inhibition of FSCA. Despite the presence of such a high degree of receptor reserve, a range of intrinsic activities was displayed by structurally diverse classes of compounds. For example, sumatriptan and lysergol were as efficacious as 5-HT itself and thus acted as full agonists, whereas metergoline and 1-NP behaved as partial agonists and as shown previously (Adham et al. 1993a), methiothepin was a silent antagonist (Kb = 438 nM).We have also investigated activation of additional signal transduction pathways by the 5-HT1F receptor and found that the responses differ in the two cell lines with respect to stimulation of phospholipase C. For example, in NIH-3T3 cells no elevation of inositol phosphates (IP) of [Ca2+]i was observed even at very high agonist concentrations (100 M). In contrast, in LM(tk–) cells concentrations of 5-HT as low as 10 nM induced stimulation of IP and a rapid increase of [Ca2+]i. The 5-HT1F receptor failed to alter arachidonic acid release in either cell line.The maximal increase in IP accumulation in LM(tk–) cells was modest, averaging about 100% above basal. The increases of IP and [Ca2+]i required 5-HT concentrations less than one order of magnitude greater than those inhibiting FSCA (EC50 = 17, 55 and 8 nM, respectively), and both responses were blocked by 100 M methiothepin. All three responses (cAMP, IP, and [Ca2+]i) were sensitive to pertussis toxin pre-treatment, suggesting the involvement of Gi/Go protein(s) in these signal transduction pathways. [Ca2+]i was also elevated by sumatriptan, which may provide a mechanism by which this drug causes constriction of the vasculature. In conclusion, these data indicate that the human 5-HT1F receptor can couple to multiple effectors, and that this coupling is cell-type dependent.Abbreviations FSCA
forskolin-stimulated cAMP accumulation
- [Ca2+]
intracellular free calcium concentration
- AA
arachidonic acid
- EEDQ
N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline
- CHO
chinese hamster ovary cell
- LM(tk–)
mouse fibroblast cell
- Bmax
maximal binding site density
- Ki
apparent dissociation constant obtained from competition binding studies
- G protein
guanine nucleotide-binding protein
- HBS
HEPES-buffered saline
- IP
inositol phosphates
- IP3
inositol 1,4,5 trisphosphate
- PLC
phospholipase C
- Kb
antagonist dissociation constant
- Kd
equilibrium dissociation constant
- N-1F-6
stable NIH-3T3 cells expressing the cloned 5-HT1F receptor
- L-1F-3
stable LM(tk–) cells expressing the cloned 5-HT1F receptor
- PTX
pertussis toxin
- BSA
bovine serum albumin
- METH
methiothepin
- SUMA
sumatriptan
- 5-MeO-DMT
5-methoxy-N,N-dimethyltryptamine
- 1-NP
1-(1-napthyl)piperazine
- 5-CT
5-carboxyamidotryptamine
Correspondence to: N. Adham at the above address 相似文献
997.
J. Pfeilschifter H. Mühl W. Pignat F. M?rki H. van den Bosch 《European journal of clinical pharmacology》1993,44(Z1):S7-S9
Phospholipase A2 (PLA2) is believed to play an essential role in inflammatory processes by releasing arachidonic acid from membrane phospholipids for synthesis of important lipid mediators, such as prostaglandins, leukotrienes and platelet activating factor.We have used glomerular mesangial cells as a model system to study the regulation of PLA2 under inflammatory conditions. Potent pro-inflammatory cytokines, such as interleukin 1 (IL-1) and tumour necrosis factor (TNF), as well as agents that increase cellular cAMP levels have been found to increase Group II PLA2 gene expression in a time- and dose-dependent manner. 相似文献
998.
T. M. de Reijke P. C. N. Vos E. C. de Boer R. F. M. Bevers W. H. de Muinck Keizer K. H. Kurth D. H. J. Schamhart 《Urological research》1993,21(5):349-352
Summary The study was initiated as an in vitro approach to the situation existing during intravesical bacillus Calmette-Guerin (BCG) instillation in patients with superficial bladder cancer. Cytokine secretion of a human bladder carcinoma cell line T24 treated with BCG was investigated. A 24-h treatment of T24 cells with BCG resulted in a tenfold higher secretion of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF) when compared with T24 cells treated with Escherichia coli, Streptococcus faecalis or a cell wall preparation of Nocardia rubra (N-CWS). No secretion of IL-1 and IL-2 was detected. Pre-exposing T24 cells to BCG for various periods of time indicated that a minimum exposure time of 0.5–1 h was required to upregulate IL-6 and TNF production. Extending the BCG pre-exposure time to 2 and 3 h further increased the rate of cytokine production. No significant difference was found, however, between the rate of secretion initiated after a 2-h or 3-h pre-exposure period. The amounts of these cytokines secreted in the presence of BCG-conditioned medium did not differ significantly from the constitutively secreted amounts, excluding an effect of products possibly secreted by BCG on the upregulation of IL-6 and TNF. In addition, upregulation of cytokine production appeared to be dependent on the concentration of BCG. The results suggest that cytokines may be produced by urothelial tumor cells after intravesical instillation in patients with superficial bladder cancer, which may play a role in the mode of action of BCG. 相似文献
999.
Masaaki Oka Hitoshi Mitsunaga Shoichi Hazama Shigefumi Yoshino Takashi Suzuki 《Surgery today》1993,23(8):669-674
The natural killer (NK) activity of peripheral blood mononuclear cells and serum immunosuppressive acidic protein (IAP) levels were examined in patients with esophageal or gastric cancer, before and after surgery. Patients with stage IV esophageal or stage IV gastric cancer had significantly lower NK activity (39.5±14.8% and 37±11.6%, respectively), and also higher serum IAP levels (778±264 g/mL and 633±156 g/mL, respectively), than the corresponding control values (50±5.6% and 375±26 g/mL, respectively). Patients with esophageal or gastric cancer who underwent curative resection had high NK activity (54.8±11.6% and 54.8±8.0%, respectively), and low IAP levels (471±116 g/mL and 490±42 g/mL, respectively), compared with those who underwent non-curative resection. Patients who underwent non-curative resection had lower NK activity and higher serum IAP levels than those who underwent curative resection, even 1 month after surgery. Mononuclear cells in the regional lymph nodes and tumor specimens showed significantly lower NK activity than those in the peripheral blood and spleen. Thus, NK activity and the IAP level reflected the immunocompetence, clinical course, and surgical curability of those patients. NK cells appeared not to have any significant antitumor activity in the regional lymph nodes or in the tumor itself, although they were still active in the peripheral blood. 相似文献
1000.
<正> The effect of radiation on lymphocyte subpopulations and T cell subsets of peripheral blood was studied in mice after X- and y-irradiation.lt was found that (1) there were neither marked changes in the percentage and absolute number of acid alpha-naphthol acetyl esterase "positive(ANAE + )cells of different granular patterns, nor significant lowering of the T11/Ts ratio after single whole body X-irradiation in the dose range of 25-250 mGy with a dose rate of 12.5mGy/min. At the same time no significant changes were found at different time intervals after irradiation. After continuous low level irradiation with 60Co γ-rays with a dose rate of 5.4 mGy/6h.d,the ANAE grauular pattern of lymphocytes showed no significant changes with cumulative doses of 32.4 -520 mGy. (3)There was no decrease in the "splenocyte Ts index in Kunming mice after low dose X-irradiation. The results suggest that the stimulatory effect of low dose radiation on the PFC reaction can not be explained on the basis of a decrease in num 相似文献