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1.
RP215 monoclonal antibody (Mab) was shown to recognize a specific carbohydrate-associated epitope found in cancer cell-expressed glycoproteins, known as CA215. The membrane-bound and soluble forms of CA215 were detected in almost all of the cancer cells in humans, but rarely found in normal tissues. Through MALDI-TOF MS analysis, it has been reported previously that as much as 40% of the detected tryptic peptides of CA215 showed high degrees of sequence homology to those found in immunoglobulin heavy chains. The cancer cell-derived immunoglobulins were further purified from CA215 by affinity column-linked with goat anti-human IgG for molecular characterizations. Semi-quantitative RT-PCR was used to determine the mRNA levels of various immunoglobulin genes expressed by cancer cells of single or multi-cell origins and compared with those found in normal human serum. The stability of CA215 was investigated under different experimental conditions. It was observed that the RP215-specific epitope in CA215 is stable at neutral pH, in human serum or in mice (half life of 5–18 days), but unstable at extreme pH’s (pH ≤ 2.0; pH ≥ 12.0) or high temperatures. Enzyme immunoassays were performed with several secondary antibody probes related to human IgG. It was demonstrated that cancer cell-expressed immunoglobulins with RP215-specific epitope have much lower immunoactivity than that of normal human IgG (≤ 5%), despite the fact that both showed almost identical amino acid sequence in the respective Fc region reported previously. This could be the result of aberrant glycosylation of CA215 in cancer cells. Aberrant glycosylation of glycoproteins may have important biological implications on the proliferation of cancer cells in vitro or in vivo.  相似文献   
2.
 胞嘧啶与鸟嘌呤二核苷酸序列(CpG ODN)是一段以非甲基化胞嘧啶与鸟嘌呤(CpG)为核心的碱基序列,能够激活体内的多种免疫细胞,发生免疫应答,抵抗疾病。调节CpG的结构,化学修饰可提高CpG的生物活性, 提高CpG作为免疫佐剂和放疗、化疗增敏剂治疗肿瘤的效果。  相似文献   
3.
枸杞多糖免疫调节作用机制研究进展   总被引:23,自引:0,他引:23  
枸杞子是传统的名贵补益中药,具有"滋阴补血、益精明目"之功效.枸杞多糖是其中的主要生物活性成分,具有免疫调节、抗肿瘤、抗衰老等多种生物学作用.近年来,随着植物化学分离纯化技术的不断改进,枸杞多糖得到了进一步的分离和纯化,因此其免疫作用的分子机制如其作用的靶细胞、信号转导途径等研究取得了较明显进展.  相似文献   
4.
目的 研究链霉菌多糖(SMP)对正常小鼠和免疫抑制模型小鼠的免疫调节活性.方法 通过混合淋巴细胞培养方法检测SMP对正常小鼠脾脏淋巴细胞增殖作用的影响,用酸性α-醋酸萘酯酶染色法观察免疫抑制小鼠模型外周血中T淋巴细胞的变化,以及流式细胞仪检测免疫抑制模型小鼠脾细胞中T细胞亚群Lyt2 和L3T4 的比例变化.结果 SMP可以明显促进混合淋巴细胞的增殖,并对免疫抑制模型小鼠T淋巴细胞的抑制有保护作用,还可以调节模型小鼠CD4 /CD8 的比值至正常水平.结论 SMP具有调节免疫功能的作用.  相似文献   
5.
Polysaccharides were extracted from young branches of Morus alba L. (M); a green alga, Chlamydomonas mexicana Lewin, (C1 and C2) and a fungus, Poria cocos (Fr.) Wolf, (P1 and P2). M consisted of rhamnose, arabinose, xylose, mannose, galactose and glucose, C1 of fucose, 2-MeO-arabinose, ribose, arabinose, 6-MeO-mannose, xylose, 2-deoxy-galactose, mannose, galactose and glucose, C2 of 3-MeO-arabinose, arabinose, xylose, 2-MeO-galactose, galactose and glucose, P1 was mannose, galactose, glucose and a small amount of ribose and P2 consisted of erythritol, arabinose, glucose and muramic acid with the ratio of 1:1:4:1. Pharmacological tests for all of these polysaccharides were performed. Based on the results, M was less effective, but C1 and C2 were immunostimulant either in humoral immunity or in cellular immunity. C2 was effective in nonspecific immunity only, and P1 was as effective in humoral or in nonspecific immunities. P2 expressed enhancement in humoral, cellular or nonspecific immunities, but its activities were less than P1.  相似文献   
6.
人血清泌乳素生物活性与免疫活性的不一致性   总被引:2,自引:0,他引:2  
刘孟元  周肃 《天津医药》1991,19(5):268-271
本研究利用放射免疫分析法和放射受体分析法对几种不同病理条件下的人血清泌乳素水平进行了测定,并对其生物活性和免疫活性的变化作进一步探讨。结果发现,垂体泌乳素腺瘤患者血清泌乳素的比生物活性(8.6±7.4IU/mg)明显低于健康正常对照(26.5±14.4IU/mg,P<0.001);而垂体非泌乳素腺瘤(包括生长激素腺瘤、促肾上腺皮质激素腺瘤和无分泌功能腺瘤)患者血清泌乳素水平虽然明显升高(P<0.05),但其比生物活性与正常对照则无显著性差异;舞蹈手足徐动症和帕金森氏病患者无论血清泌乳素水平,还是其比生物活性与正常对照的差异均无显著性。  相似文献   
7.
The serum concentrations of digoxin-like immunoactivity (DLIA) were measured in 99 patients: 20 healthy volunteers (HV), 15 patients with insulin-dependent diabetes mellitus (IDDM), 14 patients with non–insulin-dependent diabetes mellitus without hypertension taking oral hypoglycemic (OHA) agents (NIDDM/−HT), 11 patients with NIDDM without hypertension taking insulin (NIDDM/−HT+INS), 12 NIDDM patients with hypertension taking OHA (NIDDM/+HT), nine NIDDM patients with hypertension taking insulin (NIDDM/+HT/+INS), 10 patients with essential hypertension with normal insulin levels (HT/−HI), and in eight patients with essential hypertension with hyperinsulinemia (HT/+HI). The numbers (%) of subjects with DLIA levels above the detection limit of the assay used (> 0.1 nmol/L) were, in the NIDDM/−HT group, 12/14 (85.7%) and in the NIDDM/+HT group, 9/12 (75%), significantly higher (P < .05) than in the HV (7/20; 35%), IDDM (3/15; 20%), and HT/−HI groups (2/10; 20%). The number and percentage of subjects with DLIA levels above the detection limit in the HT/+HI group was six of eight (75%), significantly (P < .05) higher than in the IDDM and HT/−HI groups, and tended to be higher than in the HV group (P < .055). Means and SD of serum DLIA levels (nmol/L) in the NIDDM/−EH (0.18/0.09) and NIDDM/+EH (0.19/0.15) groups were significantly higher (P < .05) than in the HV (0.09/0.07), IDDM (0.05/0.05), and EH/−HI (0.06/0.06) groups. DLIA levels in the HT/+HI group (0.15/0.12) were significantly higher (P < .05) than in the IDDM and HT/−HI groups. The percentage of DLIA levels above the detection limit, as well as the mean and SD of DLIA in the NIDDM group taking OHA, did not differ from those in subjects taking insulin. In all subjects studied (n = 99), DLIA correlated with C-peptide (r = 0.30; P < .01) and glomerular filtration (GF) (r =− 0.21; P < .05). After exclusion of insulin-treated patients, DLIA correlated significantly with plasma glucose (PG; r = 0.25; P < .05), immunoreactive insulin (IRI; r = 0.41; P < .001), C-peptide (r = 0.27; P < .05), and GF (r =− 0.26; P < .05) (n = 64). Correlation of DLIA with IRI (r = 0.33; P < .05; n = 38) also persisted after exclusion of patients taking insulin and those with DLIA levels below the detection limit. Similarly, DLIA also correlated with C-peptide (r = 0.64; P < .05) and IRI (r = 0.70; P < .05) in the subgroup of 10 patients with the highest levels of DLIA (> 0.25 nmol/L). None of the sera (n = 15) with different DLIA concentrations (0.0–0.38 nmol/L) exhibited K-pNPPase (Na+-K+-ATPase) inhibitory activity. In conclusion, this work demonstrated elevated serum DLIA in NIDDM and HT/+HI patients, and its correlation with IRI and GF. However, due to the fact that the chemical nature and biologic properties of DLIA are still a matter of debate, it is too early to speculate whether the elevation of DLIA is just a secondary result associated with HI and reduced GF, or whether it also has pathophysiologic consequences. Nevertheless, in both cases the elevated concentrations of substances with DLIA and their interference with antidigoxin antibodies may affect therapeutic monitoring of digitalization in NIDDM and HT/+HI patients. Also, the elevated DLIA could subclassify these patients. The significance of such subclassifications (pathophysiologic, therapeutic, or prognostic), however, will need further investigation.  相似文献   
8.
The existence of a heterogeneous population of follicle stimulatinghormone (FSH) was described many years ago. Other pituitaryglycoproteins, such as thyroid stimulating hormone (TSH) andluteinizing hormone (LH) as well as placental human chorionicgonadotrophin (HCG) also exhibit heterogeneity. Because FSHplays a significant role in a variety of ovarian activitiessuch as follicular maturation, selection of the dominant follicleand ovulation, the possible role of sub-populations of FSH withdistinct physicochemical characteristics is of great interest.After a great deal of investigation, the physiological significanceof this biochemical phenomenon has yet to be fully understood.Investigators have employed immunoassays, in-vitro bioassaysand radioreceptor assays to study the biological activity ofthe individual isoforms ofFSH. As more informations has accumulated,it has become clear that some ofthe initial assumptions usedto interpret data may be incorrect. This review is Providedto Update the reader with availableinformation on the topicas it relates to FSH and to pointout issues that require re-evaluationin this area.  相似文献   
9.
目的:鉴定自制的抗CD3-抗胶质瘤双特异性抗体(双抗)的双向结合能力,测定其免疫活性及其对T淋巴细胞的作用.方法:用标化凝胶柱洗脱、免疫组化等方法对自制双抗的相对分子质量及双向结合能力进行测定,用酶联免疫吸附试验(ELISA)等方法对双抗的双向免疫活性及其对T淋巴细胞表型的作用进行测定,并观察T淋巴细胞形态的变化.结果:经洗脱证实该双抗相对分子质量为11万;经双抗作用后,胶质瘤细胞和淋巴细胞阳性染色率分别>80%和>90%;免疫活性测定显示双抗不仅可与T淋巴细胞结合(结合效价为1∶32 000),还可结合胶质瘤细胞(结合效价为1∶8 000);在细胞表型方面,被双抗活化时,CD3+细胞数占绝大多数,CD8+细胞比例随着培养时间的延长逐渐增加.结论:所制备的复合物确系具有双向结合能力的双抗,有双向免疫活性,并可活化T淋巴细胞.  相似文献   
10.
枸杞糖缀合物LbGp2的理化性质和活性研究   总被引:5,自引:0,他引:5  
目的 分离纯化枸杞糖缀合物(LbGp2 )并研究其理化性质及活性。方法 采用柱色谱法得到LbGp2 ,经HPLC ,CE ,GC ,SEC及糖含量分析、元素分析和氨基酸分析等研究其理化性质,并用半体内法、形态学计数法和比色法等研究了Lbp2对腹腔巨噬细胞吞噬功能、淋巴细胞的转化以及对小鼠血清半数溶血等的影响。结果 LbGp2是均一组份,其分子量为6.8×104,糖含量为90.7% ,糖组成为Ara Gal 3∶4(摩尔比) ,并含有18种天然氨基酸。免疫活性试验表明Lbp2具有显著的免疫增强作用。同时还具有很好的抗氧化作用。结论 LbGp2是均一的糖缀合物,有免疫活性和抗氧化活性  相似文献   
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