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101.
Benjamin Sadlack Ralf Kühn Hubert Schorle Klaus Rajewsky Werner Müller Ivan Horak 《European journal of immunology》1994,24(1):281-284
Interleukin (IL)-2 and IL-4 are considered as important regulators of growth and differentiation of lymphocytes. We report that in mice made deficient for both IL-2 and IL-4 by gene targeting all major T cell subsets and B cells were normal, indicating that IL-2 and IL-4 are not essential for development of the immune system. Paradoxically, proliferation of T cells was increased in both IL-2- and IL-4-deficient homozygous mice. 相似文献
102.
ImmunoadjuvantactionofliposomesforentrappedJapaneseEncephalitisvirusE-glucoprotein¥HuJun(胡军);MaWenyu(马文煜);HuangQingsheng(黄庆生)... 相似文献
103.
小柴胡汤口服液药效作用的研究 总被引:2,自引:0,他引:2
观察了小柴胡汤口服液的主要药理作用。研究表明,小柴胡汤口服液有显著抑制角叉菜胶诱发的大鼠踝关节水肿(p<0.05),保护四氯化碳所致的大鼠急性肝功能损害,有极显著降低血清SGPT及LDH的作用(P<0.01)。对家兔发热反应也有较好的抑制作用。此外,小柴胡汤口服液对小鼠兔疫反应也有一定的增强作用,可促进小鼠碳粒廓清速率,提高血清溶血素水平及增强鸡红细胞所致的迟发性过敏反应。 相似文献
104.
Chy-3 mice are Vegfc haploinsufficient and exhibit defective dermal superficial to deep lymphatic transition and dermal lymphatic hypoplasia. 总被引:1,自引:0,他引:1
Michael T Dellinger Robert J Hunter Michael J Bernas Marlys H Witte Robert P Erickson 《Developmental dynamics》2007,236(8):2346-2355
Recent advances in molecular lymphology and lymphatic phenotyping techniques in small animals offer new opportunities to delineate mutant mouse models. Chy-3 mutant mice were originally named for their chylous ascites, but the underlying lymphatic disorder was not defined. We now re-examined these mice and applied advanced genotyping and lymphatic phenotyping techniques to pinpoint the specific lymphatic defect in this mouse model. We demonstrated that Chy-3 mice carry a large chromosomal deletion that includes Vegfc and narrowed this region by monitoring the heterozygosity of genetic markers. We found that Chy-3 mice not only exhibited chylous ascites but also lymphedema of the hind paws and, in approximately half of the males, lymphedema of the penis. Visual lymphangiography and immunofluorescence staining showed a hypoplastic dermal lymphatic network, whereas the blood vasculature appeared unaffected. This hypoplastic lymphatic network was functional, and all adult Chy-3 mice exhibited a lateral lymphatic pathway directly connecting the inguinal to the axillary lymph node. The dermal superficial to deep lymphatic connections in upper limbs and in all cervical regions were intact and functionally drained the upper body. Lymphatic tracer was not transported from the dermal to the deep truncal lymphatic system in the lower limbs, even though the deep lymphatic vessels and nodes were present and patent. These findings further delineate the lymphatic phenotype of Chy-3 mice, identify a collateral lymph drainage pathway previously undescribed in other genetic models of lymphedema, and demonstrate a predilection for lymphatic abnormalities of the lower limbs. 相似文献
105.
目的观察奥明格健脑口服液对改善小鼠记忆作用的影响。方法断乳小鼠,体重12~14g,每组14~16只。把实验动物随机分为正常对照组、高剂量组、中剂量组和低剂量组,连续给样30d,进行跳台和水迷宫试验,以上试验按同样方法重复一次。结果两次小鼠实验表明,灌胃奥明格健脑口服液1mo后,跳台试验中受电击动物数和错误总数,各试验组均低于对照组,其中高剂量试验组显著低于对照组,而且潜伏期显著延长。水迷宫试验中,动物到达终点所需时间和错误总数,高中剂量组试验组均显著低于对照组。结论奥明格健脑口服液具有改善动物记忆的作用。 相似文献
106.
Michael S. Boosalis Tohru Ikuta Betty S. Pace Silvana da Fonseca Gary L. White Douglas V. Faller Susan P. Perrine 《Blood cells, molecules & diseases》1997,23(3):434-442
ABSTRACT: Short-chain fatty acids, such as butyrate and propionate, induce fetal globin gene expression and are under clinical investigation in the β-hemoglobinopathies. Limitations of the short-chain fatty acids as therapeutics include their rapid metabolism and a tendency to induce cell growth arrest if administered for prolonged periods. In studies described here, the cellular effects of other inducers of fetal globin, phenoxyacetic acid and derivatives of short-chain fatty acids and cinnamic acids, were investigated in the human erythroid cell line K562, the IL-3 dependent multi-lineage cell line (32D), and in mice and primates. Several test compounds supported 32D cell proliferation despite a 50-fold depletion of IL-3, which resulted in growth arrest and apoptotic death in control cells. The degree of proliferation induced by certain test compounds was similar to the degree of proliferation induced by Erythropoietin and G-CSF in the cells. Eight of ten compounds induced γ globin mRNA in K562 cells. A 2.5 to 6-fold increase in reticulocytosis was observedin vivoin mice treated with two prototype compounds. Pharmacokinetic studies of three prototype compounds demonstrated millimolar plasma concentrations after single oral doses for many hours in primates. These findings identify orally bioavailable compounds which induce γ globin gene expression and hematopoietic cell proliferation through an activity which partially abrogates requirements for IL-3. Such compounds provide potential for oral therapeutics which stimulate proliferation of hematopoietic cells of multiple lineages, as well as inducing fetal globin. 相似文献
107.
Enhanced in vivo cytotoxicity of recombinant human tumor necrosis factor with etoposide in human renal cell carcinoma 总被引:1,自引:0,他引:1
Summary The combination of tumor necrosis factor (TNF) and etoposide (ETP) was evaluated for potential cytotoxic efficacy against a human renal cell carcinoma xenograft using an in vivo assay employing an athymic mouse host with tumor implanted a the subrenal capsule site. Both antitumor efficacy (relative survival or RTS) and toxicity (weight loss) of TNF and ETP alone and in combination were evaluated. While TNF and ETP alone were mildly inhibitory (RTS 90% and 71%, respectively), the combination caused marked tumor inhibition (45% of controls). Host toxicity encountered with the combination did not exceed the toxicity associated with ETP alone, suggesting that the therapeutic index may have been augmented. It is concluded that enhanced antitumor activity without substantial augmentation of toxicity is observed with this combination, providing a rationale for further evaluation of tumor necrosis factor-based regimens for the treatment of advanced renal carcinoma.Supported by a Merit Review grant, VA Medical Research Service, Durham, NC 27710, USA 相似文献
108.
用微量甲基纤维素培养方法探讨冬虫夏草结晶制剂(CS-Cr)对小鼠骨髓红系祖细胞(CFU-E和BFU-E)增殖的影响。实验结果表明,CS-Cr明显提高骨髓CFU-E和BFU-E产率、自杀率,并能对抗三尖杉酯碱对造血机能的损害。采用液体培养技术发现CS-Cr促进骨髓成纤维祖细胞(CFU-F)增殖,其产率变化与CFU-E和BFU-E产率变化一致。 相似文献
109.
This study was designed to investigate the effect of morphine on formalin-induced nociceptive responses in streptozotocin (STZ) induced-diabetic mice, noninsulin-dependent genetically diabetic db/db mice and their respective controls (ddY and +/+). In nondiabetic (ddY and +/+) mice, morphine (1–10 mg/kg, PO) dose dependently attenuated the biphasic nociceptive responses induced by SC injection of formalin to the hindpaw, demonstrating equipotency on both the first and second phases. Para-chlorophenylalanine (800 mg/kg × 2, PO) and pindolol (1 mg/kg, IP) reduced the effect of morphine on the first phase, sulpiride (10 mg/kg, IP) abolished the effect on both phases, while ketanserin (1 mg/kg, IP) had no effect. In STZ (200 mg/kg, IP)-diabetic mice, morphine weakly attenuated the nociception in comparison to control ddY mice, whereas it had comparable effects in both the first and second phases of control +/+ mice and db/db mice. The serotonergic agonist, meta-chlorophenylpiperazine (0.32–3.2 mg/kg, PO), dose dependently attenuated the biphasic nociceptive responses to formalin in both phases of diabetic mice; however, FR64822, a dopaminergic compound (0.1–10 mg/kg, PO), had little effect. We speculate that activation of both dopaminergic (DA)- and serotonergic-mediated mechanisms are potentially responsible for the effect of morphine on the first phase, while the DA-mediated effect is involved in the second phase. The DA-mediated mechanism, but not the serotonin-mediated one, appears to be altered in both STZ-diabetic and db/db mice. These results suggest that the attenuated effects of morphine might be due to a dopaminergic dysfunction in STZ mice, and that there might be other mechanisms compensating for this attenuation of dopaminergic function in db/db mice. 相似文献
110.
Ultraviolet radiation (UVB) in sunlight is known to have multiple effects on the immune system. Evidence suggests that UVB-induced immunosuppression is mediated in part by immunosuppressive and immunoregulatory cytokines. Our studies have utilized gene-targeted mutant mice to determine key molecular requirements essential for the development of UVB-induced immunosuppression. Preliminary results from our laboratory suggest that TNF-α plays a regulatory role in contact hypersensitivity, but is not a crucial factor for UVB-induced immunosuppression, and that multiple factors are involved in the induction of UVB mediated immunosuppression. 相似文献