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排序方式: 共有504条查询结果,搜索用时 15 毫秒
81.
目的:考察鲎试剂方法检测注射用盐酸丙帕他莫中细菌内毒素的可行性。方法:参照《中国药典》2010年版(二部)附录ⅪE细菌内毒素检查法对注射用盐酸丙帕他莫进行细菌内毒素检测。结果:质量浓度为5.0 mg·ml-1的样品溶液对凝集反应有抑制作用,质量浓度稀释至2.5 mg·ml-1时,用灵敏度λ为0.25 EU·ml-1的鲎试剂进行试验,干扰作用消失。结论:注射用盐酸丙帕他莫可用鲎试剂方法进行细菌内毒素检测。  相似文献   
82.
目的:确立用鲎试剂(TAL)法检测泛影葡胺注射液中的内毒素。方法:参照《美国药典》23版及《中国药典》1995年版二部收载的细菌内毒素检查方法的要求进行试验。结果:用标示值灵敏度为0.5EU.ml^-1的鲎试剂检查泛影葡胺注射中的细菌内毒素是有效的。结论:0.5EU.ml^-1鲎试剂可以用于泛影葡胺注射液中的内毒素检测。鲎试剂(TAL)法可替代泛影葡胺注射液热原检查项目中的家兔(RT)法。  相似文献   
83.

Background:

B7-H3, an immunoregulatory protein, is overexpressed in several cancers and is often associated with metastasis and poor prognosis. Here, our aim was to identify microRNAs (miRNAs) regulating B7-H3 and assess their potential prognostic implications in breast cancer.

Methods:

MicroRNAs targeting B7-H3 were identified by transfecting two breast cancer cell lines with a library of 810 miRNA mimics and quantifying changes of B7-H3 protein levels using protein lysate microarrays. For validations we used western immunoblotting and 3′-UTR luciferase assays. Clinical significance of the miRNAs was assayed by analysing whether their expression levels correlated with outcome in two cohorts of breast cancer patients (142 and 81 patients).

Results:

We identified nearly 50 miRNAs that downregulated B7-H3 protein levels. Western immunoblotting validated the impact of the 20 most effective miRNAs. Thirteen miRNAs (miR-214, miR-363*, miR-326, miR-940, miR-29c, miR-665, miR-34b*, miR-708, miR-601, miR-124a, miR-380-5p, miR-885-3p, and miR-593) targeted B7-H3 directly by binding to its 3′-UTR region. Finally, high expression of miR-29c was associated with a significant reduced risk of dying from breast cancer in both cohorts.

Conclusions:

We identified miRNAs efficiently downregulating B7-H3 expression. The expression of miR-29c correlated with survival in breast cancer patients, suggesting a tumour suppressive role for this miRNA.  相似文献   
84.
复方钾钙镁液中细菌内毒素检查法的可行性研究   总被引:2,自引:0,他引:2  
蔡慎  郑英丽  陈宝玲  方丽 《中国药房》2010,(21):1997-1998
目的:建立心脏跳停液——复方钾钙镁液的细菌内毒素检查法。方法:利用鲎试剂,依据《中国药典》2005年版二部附录细菌内毒素检查法中的凝胶半定量试验方法对3批复方钾钙镁液进行检查。结果:复方钾钙镁液经6倍以上稀释后进行试验可排除干扰因素,用半定量法估算3批样品中细菌内毒素的含量分别为0.36、0.36、0.255EU·mL-1,均小于规定限值1.5EU·mL-1。结论:所建立的半定量分析方法检查复方钾钙镁液中的细菌内毒素是可行的。  相似文献   
85.
背景:干细胞具有“环境依赖性分化”特性,以心肌组织裂解液模拟心肌微环境诱导骨髓间充质干细胞向心肌细胞方向分化的研究甚少。 目的:观察心肌组织裂解液对大鼠骨髓间充质干细胞向心肌细胞方向分化的影响。 方法:选用生长良好的第2代骨髓间充质干细胞,加入诱导液连续培养5周,连续观察细胞形态学特征的变化规律,采用α-Actin进行免疫细胞化学染色观察干细胞是否向肌细胞方向分化,收集诱导后的细胞行苏木精-伊红染色观察是否存在闰盘,并通过电镜观察其超微结构。 结果与结论:加入诱导液后大部分细胞呈“竹节样”,α-Actin免疫细胞化学染色阳性,表明间充质干细胞向肌细胞方向分化;苏木精-伊红染色可见闰盘,透射电镜下见排列整齐明暗相间的肌丝,扫描电镜下可见胞浆内有纤维状结构,说明“竹节样”细胞具有心肌细胞的典型形态结构特点。连续诱导12 d多个区域出现成片的、具有自律性搏动的多核肌管结构。心肌组织裂解液可模拟心肌细胞的微环境,诱导骨髓间充质干细胞分化为具有典型形态结构特征和相应功能活动的心肌样细胞。  相似文献   
86.
Wang Y  Li Y  Wang D  Li Y  Chang A  Chan WK 《Cancer letters》2012,320(1):111-121
The aryl hydrocarbon receptor nuclear translocator (ARNT) heterodimerizes with hypoxia inducible factor-1α (HIF-1α), followed by upregulation of genes that are essential for carcinogenesis. We utilized a novel peptide (Ainp1) to address whether the HIF-1α signaling could be suppressed by an ARNT-mediated mechanism. Ainp1 suppresses the HIF-1α-dependent luciferase expression in Hep3B cells and this suppression can be reversed by ARNT. Ainp1 reduces the interaction between ARNT and HIF-1α, suppresses the formation of the HIF-1 gel shift complex, and suppresses the ARNT recruitment to the vegf promoter. These effects are partly mediated by redistribution of the nuclear ARNT contents to the cytoplasm.  相似文献   
87.
Background  Platelets play a pivotal role in wound healing. Their beneficial effect is attributed to the release of bioactive substances, although the involved mechanisms are mostly unknown.
Objectives  To investigate mechanisms underlying platelet-induced wound healing using HaCaT keratinocytes, representing an in vitro model of proliferating and migrating keratinocytes.
Methods  Cells were exposed to platelet lysate (PL) purified from whole blood samples. Cell metabolism and proliferation were assessed using MTS and crystal violet assays, respectively, wound healing was assessed by scratch wound assay and cell migration by transwell assay. Extracellular signal-regulated kinase (ERK) 1/2 and p38 activations were studied using Western immunoblotting and intracellular Ca2+ dynamics by confocal imaging.
Results  Wound closure rates showed a significant increase at 6 and 24 h in cells exposed to nontoxic 20% PL. The cell migration assay showed a strong chemotactic effect toward PL. The intracellular Ca2+ chelator BAPTA-AM induced 100% inhibition of the PL effect on wound closure rate, while among the kinase inhibitors, SB203580 exerted about 50% inhibition, and PD98059, wortmannin and LY294002 about 30% inhibition. SB203580 and BAPTA-AM induced 100% inhibition of the PL effect on cell migration, PD98059 about 50% inhibition, and wortmannin and LY294002 no significant inhibition. Confocal imaging allowed detection of a sustained Ca2+ transient in PL-treated cells, while Western blot showed a more rapid activation of p38 than of ERK1/2.
Conclusions  Data indicate that PL increases wound healing rate by stimulating keratinocyte migration through a calcium- and p38-dependent mechanism. ERK1/2 and phosphoinositide-3 kinase seem to play minor roles.  相似文献   
88.

Background

An improved nonavalent PorA native outer membrane vesicle vaccine was developed with intrinsic adjuvating activity due to presence of less-toxic (lpxL1) LPS. In the present study, the safety and immunogenicity of this next-generation NonaMen vaccine were evaluated following repeated vaccination in rabbits and mice.

Methods

A repeated–dose toxicology study was performed in rabbits. Immunogenicity of next-generation NonaMen was evaluated by determining the serum bactericidal antibody (SBA) titers against meningococcal serogroup B strains containing several PorA subtypes. Release of the pro-inflammatory cytokine, interleukin-6 (IL-6), by the human monocytic cell line (MM6) was measured to estimate pyrogenic activity.

Results

No toxicologically relevant findings were noted in vaccinated rabbits receiving plain next-generation NonaMen. In agreement, next-generation NonaMen induced reduced amounts of the pro-inflammatory cytokine, IL-6, released by human monocyte cell line. In both rabbits and mice, next-generation NonaMen induced high SBA titers against all tested MenB strains regardless of whether or not aluminium phosphate adjuvant is used.

Conclusions

The data suggest that next-generation NonaMen is a safe vaccine with the potential to develop a broadly protective immune response and encourage the start of the first clinical studies.  相似文献   
89.
Immunotherapy using dendritic cells has shown encouraging results in both haematological and non-haematological malignancies. In this study, monocyte-derived dendritic cells from patients with B-CLL were cultured for 6 days in the presence of IL-4 and GM-CSF. Autologous B-CLL T-cells were cultured alone or with B-CLL lysate-pulsed and unpulsed autologous dendritic cells. IFN-gamma secretion was assessed using ELISA. Cytotoxicity was assessed, after 21 days in culture and re-stimulation, using flow cytometry with and without blockade by anti-HLA class I, anti-HLA class II, anti-CD4, anti-CD8 and anti-TCRalphabeta monoclonal antibodies. B-CLL T cells stimulated with B-CLL lysate-pulsed autologous dendritic cells showed a significant (P = 0.0004) increase in IFN-gamma secretion and a significant (P = 0.0008) increase in specific cytotoxicity to autologous B-cell targets, but none to autologous T cell or B cell targets from healthy individuals. B-CLL T cells cultured with (non-B-CLL) B-cell lysate-pulsed B-CLL dendritic cells showed no significant response. Pulsing dendritic cells from healthy volunteers with an autologous (non-B-CLL) B-cell lysate did not stimulate proliferation, cytokine production or cytotoxicity by autologous T cells. Pulsing B-CLL dendritic cells with allogeneic B-CLL lysates and culturing with autologous T-cells elicited cytotoxicity against autologous B-CLL targets in some cases, but not in others. Cytotoxicity was significantly reduced by blocking with anti-HLA class II (P = 0.001), anti-TCRalphabeta (P = 0.03) and anti-CD4 (P = 0.046) antibodies. Phenotyping of the responding T-cell population demonstrated the majority to be CD4 positive. Our data demonstrate that HLA class II-restricted proliferative and cytotoxic T-cell responses to B-CLL can be generated using autologous dendritic cells pulsed with tumour cell lysate.  相似文献   
90.
Following kidney transplantation, urine endotoxin levels were measured among 44 patients and compared to bacterial cultures. Urine samples were collected either via transurethral catheters or – after removal of the catheter on postoperative day 4 – by midstream void. In a control group of ten healthy volunteers, urine endotoxin levels were measured daily for 10 days. Urinary endotoxin concentration was measured by means of a chromogenically modified Limulus amebocyte lysate (LAL) test. The levels among patients with positive bacteriological findings (n = 21) were always elevated ( > 0.7 EU/ml). Furthermore, there was a marked, statistically significant difference in endotoxin values between samples with bacterial growth and samples with fungal or without any growth (P < 0.001). All 21 of the 44 patients with urinary tract infection (UTI) were endotoxin-positive. Seven more patients who received antibiotics had elevated urinary endotoxin levels, but no bacterial growth in the urine culture. No bacterial infection or significant urinary endotoxin was found in the control group. In summary, the detection of urinary endotoxin in samples obtained by either suprapubic/transurethral catheters or midstream void is an early, sensitive, and specific means of diagnosis that can be carried out even during antibiotic treatment. Received: 30 June 2000 Accepted: 24 April 2001  相似文献   
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