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61.
Lymphokine-activated killer (LAK) cells modulate the effects of IL-2 on a T cell-mediated immune response. 下载免费PDF全文
P McCulloch G Gallagher L P Walsh Y Zaloom J Xie 《Clinical and experimental immunology》1991,85(3):519-524
The ability of LAK cells and/or IL-2 to affect the course of an established T cell response was examined in a delayed-type hypersensitivity (DTH) model. IL-2 greatly increased the magnitude of the response at 24 h, while LAK cells alone had no effect. The administration of LAK cells and IL-2 together also had no effect on the magnitude of the DTH response, demonstrating that LAK cells were able to remove the enhancement seen with IL-2 alone. The presence of LAK cells reduced the serum half-life of IL-2 significantly, but not to an extent able to account for the observed loss of IL-2 induced DTH enhancement. IL-2 administration influenced cell phenotypes in the spleen and draining lymph nodes (DLN), as well as increasing splenic weight; the additional presence of LAK cells markedly altered these effects of IL-2 in the spleen (but not the DLN). Taken together, these results suggest that LAK cells interact with activated T-cells within the immune system and modulate their function. 相似文献
62.
大肠癌“移行粘膜”病理变化研究——粘液组化、免疫组化及电镜观察 总被引:2,自引:0,他引:2
对200例大肠癌旁“移行粘膜”进行了粘液组化HID/AB及PAT/KOH/PAS检测,单克隆抗体MC3和CEA免疫组化标记,凝集素PNA、UEA-1及DBA受体测定,扫描电镜观察。其结果与10例正常直肠粘膜、130例癌组织、155例各型腺瘤型息肉及3-5个月胎儿大肠粘膜进行对照。结果表明大肠粘膜从良性到恶性的各阶段粘液组化及免疫组化的改变有显著差异(P<0.05或P<0.01),癌旁“移行粘膜”也存在类似癌及胎儿大肠的不成熟性病理变化,异常范围88.0%的病例在2-3cm以内。 相似文献
63.
术中应用丝裂霉素C预防翼状胬肉术后复发的疗效观察 总被引:2,自引:0,他引:2
OBJECTIVE: To explore the feasibility of intraoperative application of mitomycin C (MMC) in pterygium and observe the ultrastructure change of pterygium with or without intraoperative application of MMC. METHODS: Sixty two eyes of 57 patients with primary pterygium were randomly divided into MMC group and control group, 29 patients (32 eyes) in MMC group underwent transposition with intraoperative application of MMC (0.4 mg.ml-1 for 1 minute), whereas 28 patients (30 eyes) in control group underwent transposition. The recurrence rate, complications and side effects were observed and compared between the two groups. The ultrastructure of pterygium with or without intraoperative application of MMC was studied with transmission electron microscopy. The mean follow-up was(7.6 +/- 3.4) months (1-13 minths). RESULT: Eleven eyes of the 30 eyes in control group (36.%) showed recurrence, whereas only 2 of 32 eyes (6.3%) in MMC group showed recurrence (P < 0.005). No severe complication and side effect appeared during the follow-up. Most of fibroblasts in pterygium that underwent intraoperative MMC occurred the change of rough endoplasmic reticulum (RER) dilatation. CONCLUSION: Intraoperative MMC appears to be an effective treatment in preventing recurrence of primary pterygium. The fibroblasts in pterygium have RER dilatation after application of MMC for 1 minute during the operation. 相似文献
64.
目的研究治疗白血病的有效药物。方法将槲皮素作用于培养的NB4细胞株,应用RT-PCR及Westem bolt方法,研究不同浓度槲皮素(30、60、90μmol/L)诱导细胞24、48、72、96、120h后,急性早幼粒细胞白血病NB4细胞株中突变型p53基因及蛋白表达的情况。结果证实其在30~90μmol/L浓度时对突变型p53基因无影响,而对突变型p53蛋白的表达有抑制作用。结论本研究为槲皮素应用于急性早幼粒细胞白血病的研究提供了有效手段。 相似文献
65.
The GNAS locus is an imprinted site. The α-subunit of the stimulatory G protein (Gsα) and extralarge variant (XLαs) are the two important products of the GNAS locus. The abnormal expression of Gsα is associated with pseudohypoparathyroidism (PHP) and related disorders, including Albright hereditary osteodystrophy (AHO), pseudopseudohypoparathyroidism (PPHP), and progressive osseous heteroplasia (POH). XLαs protein can mimic the catalytic intracellular synthesis of cyclic adenosine monophosphate (cAMP) by Gsα in response to parathyroid hormone (PTH) stimulation, which may be involved in the pathogenesis of PPHP and POH in patients with paternal GNAS defects. A paternally inherited nonsense variant in the first exon of XLαs in an adult patient may be associated with fractures and osteopetrosis. The relationship between the XLαs product of the GNAS locus and bone remodeling may have been overlooked. Here, we summarize the phenotypes of genetic mouse models and clinical cases of XLαs variations and suggest that the abnormal paternal expression of XLαs may be associated with the development of POH and affect osteoblast and osteoclast differentiation. 相似文献
66.
Xin Sun Yunfeng Guo Shengdu Yang Kai Wang Lan Xie Bai Xue 《Macromolecular chemistry and physics.》2023,224(15):2300072
The poly(l -lactic acid) (PLLA)/carbon nanomaterials composite foams with hierarchical surface microstructural and internal conductive pathways are successfully prepared by a simple crystallization-assisted rapid phase separation (CARPS). The dimension and morphology of carbon nanomaterials can induce different crystallization forms to construct the hierarchical surface microstructure, and they are distributed on the phase interface of solvent and non-solvent to form conductive pathways. It is found that the heterogeneous nucleation of nanomaterials promotes a significant increase in crystallinity, and a stacked granular structure formed on the surface promotes the increase of the water contact angle to 148.7°. Foams with interconnecting pore structures contribute to the formation of 85.3% porosity and 12.33 g g−1 oil absorption. Carbon nanomaterials are distributed on the pore walls of the porous foam, which converts the foam from an insulating material to a conducting polymer. Furthermore, the uniform distribution of nanomaterials significantly affects the thermal stability of the PLLA. In belief, the multifunctional biodegradable foam, prepared by a CARPS method, makes it promising for industrial production and has potential applications in electrical conductivity, oil-water separation, and many other fields. 相似文献
67.
论述了中药材“地区习惯用药”的由来与含义,近现代和历史上的“地区习惯用药”的实例以及产生“地区习惯用药”的原因,随品种性质判明而渐趋分化等。最后提出应该积极研究,促其分化,按其本质分类处理的建议。 相似文献
68.
深圳市一孩先天性残疾家庭的二孩同类病研究 总被引:1,自引:0,他引:1
本文对深圳市1990~1997年因独生子女先天残疾通过病残儿鉴定再生育二孩的家庭进行调查,并以同期通过鉴定的后天性残疾家庭为内对照,以农村地区一孩先天残疾未经病残儿鉴定生育二孩的家庭为外对照,了解其二孩先天残疾再发情况,尤其是同类病的再发情况,拟对独生子女病残儿医学鉴定和二胎生育指标的审批工作效果进行评价,为优生工作提供依据。研究结果表明,鉴定组一孩先天残疾家庭二孩先天残疾的患病率为5.81%,与广州市1986~1991年情况类似(5.9%),高于外省(辽宁1990~1992年为1.35%)。鉴定组二胎同类病发生率为2.8%,非鉴定组为4.55%,两组比较虽无统计学差异,但病种上却有不同,鉴定组为再发风险低的血友病、先天性共转性内斜视、脑萎缩,而非鉴定组为再发风险高的先天聋哑、进行性肌萎缩。提示病残儿鉴定工作颇有成效,避免了相当一部分遗传病家庭再次生育残疾儿,但某些环节有待进一步完善;对农村一胎先天残疾家庭生育二胎也必须纳入管理范围。 相似文献
69.
70.
腹腔镜下全子宫切除术的临床评估 总被引:1,自引:0,他引:1
目的:对腹腔腔镜下全宫切除的临床价值进行评估。方法:对43 例因诊断为子宫肌瘤(33 例) 、子宫腺肌症(6例) 及子宫内膜增殖症(4 例) 的患者行腹腔镜下全子宫切除术,对同时期121 例具有同样适应症的患者行腹式全子宫切除手术。比较两组病人术中术后情况。结果:两组病人的手术时间、术中出血量无显著性差异,腹腔镜下全子宫切除术的手术时间与子宫增大有关,术中出血量与手术时间及子宫大小无关;行腹腔镜下全子宫切除术的病人手术损伤及术后阴道残端出血发生率无增高,术后疼痛的发生率明显减少,术后使用抗菌素时间、术后住院时间及术后恢复正常活动的时间缩短。结论:腹腔镜下全子宫切除术虽不能完全代替腹式全宫切除术,却是一种安全、可靠,适于临床广泛开展的手术方式。 相似文献