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排序方式: 共有811条查询结果,搜索用时 15 毫秒
11.
应用四唑盐比色法对5种骨水泥的细胞毒性的测试 总被引:4,自引:1,他引:3
0 引言 应用细胞培养法对牙科材料的生物相容性进行评价是一种简便、有效、经济的方法 .近年来 ,国内外有许多学者报道用 MTT检测细胞活性 ,并认为用 MTT法可以代替活细胞计数、同位素标记进行细胞毒性试验 .我们应用 MTT法对 5种骨水泥的细胞毒性进行了评价 ,并对有关问题进行了讨论 .1 材料和方法1.1 测试材料 1号 :生物水泥 ,2号 :羟基磷灰石人工骨 ,3号 :氰基丙烯酸酯骨水泥 1号 (自制 ) ,4号 :氰基丙烯酸酯骨水泥 2号 (自制 ) ,5号 :氰基丙烯酸酯骨水泥 3号 (自制 ) .阴性对照采用珊瑚 ,阳性对照采用聚氯乙烯 .1.2 实验步骤… 相似文献
12.
目的合成三尖杉碱吲哚类似物。方法以色胺为原料经缩合、环合、水解与脱羧反应得吲哚哌啶酮化合物,经Bischler-Napieralski反应得烯胺。通过烯胺的溴化与氧化-重排反应得到吲哚氮杂 相似文献
13.
T. J. Mühlebach H. J. Feickert K. Welte R. A. Seger 《European journal of pediatrics》1991,150(8):575-578
Variant X-linked chronic granulomatous disease (CGD) is characterised by a decreased but still measurable respiratory burst and cytochrome b content of phagocytes resulting in a clinically milder form of the disease. We examined the in vivo effect of recombinant human granulocyte-macrophage colony stimulating factor (rh-GM-CSF) on the neutrophil functions of a patient treated for liver abscess. The number of white blood cells was markedly increased at the highest dose of GM-CSF injected (30 g/kg per day). This was mainly due to a large increase in eosinophils and to a lesser extent in neutrophils. No change in the deficient neutrophil respiratory burst nitroblue tetrazolium (NBT)-reduction, superoxide (O
2
–
)-production and cytochrome b content was observed during 6 weeks of therapy with increasing doses of GM-CSF. No significant clinical improvement of the liver abscess was observed during treatment with GM-CSF. 相似文献
14.
The relationship of serum-eosinophil cationic protein and eosinophil count to disease activity in children with bronchial asthma 总被引:1,自引:0,他引:1
15.
Han JY; Kim HK; Choi BG; Moon H; Hong YS; Lee KS 《Japanese journal of clinical oncology》1998,28(12):749-753
BACKGROUND: Quality of life (QOL) assessment has emerged to measure and
quantify the balance between treatment benefit and toxicity, and has a
value in predicting response and overall survival in cancer patients.
METHODS: From July 1995 to February 1997, 38 symptomatic patients with
advanced non-small cell lung cancer (NSCLC) were treated with MIP
chemotherapy (mitomycin 6 mg/m2, ifosfamide 3000 mg/m2 and cisplatin 50
mg/m2 on day 1 every 3 weeks). Patients were assessed for QOL including
physical well-being, general symptoms and lung cancer-specific symptoms, as
well as objective response. RESULTS: The overall response rate was 38.9%
(14/36, all were partial response) and the median duration of response was
3.5 months [95% confidence interval (CI) 2.0-4.0]. The median duration of
overall survival was 7 months (95% CI 5.9-8.5). The overall improvement of
QOL was 58.3% with 21 patients feeling better on treatment. The toxicity of
chemotherapy was mild, mainly nausea/vomiting and minimal alopecia. Using
multiple clinical predictors of survival (age, histology, stage,
performance status), only change of QOL emerged significantly (P = 0.0007).
CONCLUSIONS: MIP had an endurable response and low toxicity profile, and
provided good QOL. Integral QOL data in our study provided the strong
prediction of survival in advanced NSCLC. Further experienced QOL study
will provide greatly enhanced outcome data in clinical trials.
相似文献
16.
Christoph Seger Harald R?mpp Sonja Sturm Ernst Haslinger Peter C Schmidt Franz Hadacek 《European journal of pharmaceutical sciences》2004,21(4):453-463
Supercritical fluid extracts (carbon dioxide without modifiers) of St. John's Wort (Hypericum perforatum L., Clusiaceae) were analyzed by GC-MS, HPLC-DAD and HPLC-DAD-MS. Besides the dominating phloroglucinols hyperforin (36.5 +/- 1.1%) and adhyperforin (4.6 +/- 0.1%), the extracts mainly contained alkanes (predominantly nonacosane), fatty acids and wax esters. The apolar components tended to accumulate in a waxy phase resting a top of the hyperforin-enriched phase. No components of higher polarity like naphthodianthrones were found. A set of hyperforin oxidation products was detected and tentatively assigned using HPLC-MS. 相似文献
17.
18.
Role of extracellular adenosine triphosphate in the cytotoxic T- lymphocyte-mediated lysis of antigen presenting cells 总被引:4,自引:0,他引:4
The lysis of antigen presenting cells (APCs) by cytotoxic T lymphocytes (CTLs) may be one mechanism whereby an immune response is downregulated by Staphylococcus superantigens. Disappearance of monocytes/macrophages from staphylococcal enterotoxin A (SEA)-activated peripheral blood mononuclear cell (PBMC) cultures, but not from control PBMC cultures was seen by flow cytometry. Recently, adenosine triphosphate (ATP) has been described as an effector molecule in CTL-mediated lysis of some murine tumor target cells. We have also shown that ATP caused the lysis of human macrophages, and that treatment of cells with interferon gamma (IFN gamma) rendered macrophages significantly more sensitive to ATP than untreated cells. To show that this purine nucleotide may play a role in modulating the immune system, we generated human CTLs that were stimulated with SEA, and used them as effector cells against SEA-pulsed autologous macrophages. CTLs were found to specifically lyse SEA-pulsed macrophages, while control, unpulsed, macrophages were unaffected. The addition of hexokinase, an enzyme that hydrolyzes ATP, significantly abrogated the killing of SEA-pulsed cells during the assay. In examining the mechanism of cytotoxicity, electron microscopy showed that macrophages incubated with both ATP and CTLs underwent necrosis, rather than apoptosis. From these results, it is suggested that ATP is released from CTLs during antigen presentation, and that IFN gamma- activated macrophages, which are inherently more sensitive to this mediator, are readily lysed and therefore removed from circulation, thus downregulating an immune response. 相似文献
19.
Human monocytes express interleukin-2 receptor beta (IL-2R beta) constitutively; however, the function of these receptors has not been fully delineated. We discovered that IL-2R beta directs two biologic activities in human monocytes, the release of granulocyte-macrophage colony-stimulating factor (GM-CSF) and increased susceptibility to lysis by lymphokine-activated killer cells (LAK) cells. Human monocytes were purified from peripheral blood mononuclear cells by plastic adherence and anti-CD2 plus complement lysis. By a 5-hour 51Cr-release assay, monocytes cultured in IL-2 were found to gain increasing susceptibility to LAK cells with time and this effect was dose dependent. Maximal susceptibility was obtained with a 4-day culture in 1,000 U/mL of IL-2. Monocytes were also found to release GM-CSF in response to IL-2 using a CSF-dependent cell line, Mo7e. Because IL-2- induced GM-CSF release coincides with LAK lysis of IL-2-cultured monocytes, we treated monocytes with anti-GM-CSF and anti-IL-2R beta to determine whether GM-CSF release and LAK susceptibility were dependent or independent events. We found that both phenomena were inhibited by either antibody. Therefore, we conclude that IL-2-induced release of GM- CSF is mediated by IL-2R beta, which then acts to modulate the susceptibility of monocytes to lysis by LAK cells. 相似文献
20.