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991.
The priming action of tumour necrosis factor-alpha (TNF-α) and granulocyte-macrophage colony-stimulating factor (GM-CSF) on neutrophils activated by inflammatory microcrystals 下载免费PDF全文
We studied the effects of TNF-α or GM-CSF on the production of reactive oxygen species (as measured by chemiluminescence) and degranulation responses of neutrophils to opsonized inflammatory microcrystals. TNF-α in the 10–2000 pm or GM-CSF in the 2–200 pm concentration range caused the concentration-dependent amplification of neutrophil chemiluminescence responses to both calcium pyrophosphate dihydrate (CPPD) and monosodium urate monohydrate (MSUM) crystals. Degranulation responses, as measured by the extracellular release of the granule enzymes myeloperoxidase or lysozyme, were amplified by ≈ 50–100% for both MSUM or CPPD crystal-induced neutrophil activation when cells were pretreated with TNF-α at 2000 pm or GM-CSF at 75 pm. 相似文献
992.
A sensitive and reproducible enzyme-linked immunosorbent assay (ELISA) has been developed using T cell hybridomas as coating antigen, for detection of Fc receptors for IgA (Fc alpha R). T-T hybridomas were generated from fusions of Fc alpha R+ T cell clones from mouse Peyer's patches with the Fc alpha R- R1.1 T lymphoma cell line. The 2 T-T hybridomas (designated Th HA) used here express Fc alpha R as determined by a rosette method and by ELISA. Th HA cells were cultured under conditions for maximum Fc alpha R expression, were added to individual wells of 96-well EIA plates, and were fixed in situ with glutaraldehyde. Plates were incubated with purified mouse monoclonal IgA, IgM or IgG1 and were developed with beta-galactosidase-coupled goat IgG antibodies specific for mouse heavy chains. Using the ELISA, both Th HA cell lines were shown to express significant levels of Fc alpha R, lower but detectable Fc mu R, and no discernible Fc gamma 1R. Interestingly, the rosette assay only allowed detection of receptors for IgA. When splenic lymphocytes were used, good Fc mu R and less Fc alpha R expression occurred on these cells as determined by ELISA and rosetting; however, no Fc gamma 1R cells were detected by either method. Thus, the ELISA is sensitive and reproducible, and allows an objective measurement of FcR expressed on T cells. 相似文献
993.
994.
Aim: Several studies have shown that a variety of peptides and cytokines are involved in ovarian regulatory mechanisms; however, their exact function is still unclear. In this work we study whether the administration of peptide α‐melanotropin and the cytokines interleukin‐1β (IL‐1β) and tumour necrosis factor‐α (TNF‐α) on their own modify the release of progesterone in cultured granulosa cells (GC) from pro‐oestrous rats. We also investigate an interaction between these cytokines and α‐melanotropin in the modulation of progesterone secretion. Methods: Granulosa cells were collected from the ovaries of female Wistar rats and cultured for up to 24 h in the presence of different concentrations of α‐melanotropin, cytokines or a combination of both. Progesterone concentration was measured by radioimmunoassay. Results: The addition of α‐melanotropin in a dose of 0.01 and 0.1 mm had no effect on progesterone release, whereas a dose of 1 mm significantly increased progesterone release (P < 0.01) compared with the control culture. Progesterone release was not modified when different concentrations of interleukin‐1β or TNF‐α were added to the cell cultures. However, when interleukin‐1β or TNF‐α were added simultaneously with 1 μm α‐melanotropin, a significant reduction (P < 0.01 for interleukin‐1β and P < 0.05 for TNF‐α) of the steroid release was found with respect to the α‐melanotropin‐treated group. Conclusions: These results lead us to suggest that, although α‐melanotropin stimulates progesterone release in pre‐ovulatory GC, this effect is blocked by the presence of interleukin‐1β or TNF‐α. 相似文献
995.
Elizabeth Knyihar-Csillik Laszlo Vecsei Andras Mihaly Robert Fenyo Ibolya Farkas Beata Krisztin-Peva Bertalan Csillik 《Annals of anatomy》2007,189(1):39-45
Vinpocetine, a derivate of vincamine, is widely used in the clinical pharmacotherapy of cerebral circulatory diseases. Herewith we report on a novel effect of vinpocetine: inhibition of retrograde axoplasmic transport of nerve growth factor (NGF) in the peripheral nerve. Blockade of retrograde transport of NGF results in transganglionic degenerative atrophy (TDA) in the segmentally related ipsilateral superficial spinal dorsal horn, which is characterized by depletion of the marker enzymes fluoride-resistant acid phosphatase (FRAP) and thiamine monophosphatase (TMP). At the same time, pain-related neuropeptides such as substance P (SP) and calcitonin gene-related peptide (CGRP), are depleted from lamina I-III from the segmentally related, ipsitateral Rolando substance of the spinal cord. On the basis of these experiments it is suggested that vinpocetine may result in a locally restricted decrease of nociception, that might be useful in clinical treatment of intractable pain. Pilot self-experiments support this assumption. 相似文献
996.
大学生就业效能量表的编制 总被引:1,自引:0,他引:1
刘永贤 《中国健康心理学杂志》2008,16(7):821-822
目的编制适用于我国大学生的就业的效能量表。方法在深入访谈和文献综述的基础上,编制出大学生就业效能量表,运用探索性和验证性因素分析技术对568名全日制在校本科生的就业效能的内在结构进行了探讨。结果大学生就业效能主要有3个因素组成:个性自我了解、就业信息与技能和就业应对信心,问卷的各项测量指标良好。结论本问卷可以作为测量大学生就业效能的工具。 相似文献
997.
998.
Sandra E. File S. Pellow L. H. Jensen 《Journal of neural transmission (Vienna, Austria : 1996)》1986,65(2):103-114
Summary The effects of the-carboline ZK 93426, a putative benzodiazepine receptor antagonist, were investigated in the social interaction test of anxiety and in the holeboard. Like the receptor antagonist Ro 15-1788, ZK 93426 (2.5–10 mg/kg) caused a specific reduction in social interaction (interpreted as an anxiogenic effect) and caused a significant elevation in exploratory head-dipping (5 mg/kg). When low (ineffective) doses of both compounds (1 mg/kg ZK 93426; 4 mg/kg Ro 15-1788) were administered together they significantly reduced social interaction. No further reductions in social interaction were observed when effective doses of both compounds (5 mg/kg ZK 93426; 10 mg/kg Ro 15-1788) were tested in combination; it is likely that this is due to almost total benzodiazepine receptor occupancy at effective doses of either compound. When doses of each compound (5 mg/kg ZK 93426; 10 mg/kg Ro 15-1788) that resulted in stimulation of head-dipping were examined in combination, the elevation in exploration was no longer observed. Since at higher doses of both compounds there is an attenuation of the elevation in head-dipping, it is again likely that the effects of the two compounds are additive. 相似文献
999.
Two distinct patterns of somatization were identified in 807 Swedish adopted men, using comprehensive lifetime psychiatric and sick-leave records. "Diversiform" somatizers had a high frequency of brief sickness occasions for a wide diversity of complaints, particularly pain in the head, joints, and abdomen. "Asthenic" somatizers had a lower frequency and diversity of complaints. They recuperate more slowly, however, and were more often disabled by fatigue, weakness, and minor illnesses such as upper respiratory infections. Both types of somatizers had associated psychosocial maladjustment, but they had discrete clinical patterns, with infrequent overlap. Diversiform somatizers had a higher risk of alcohol abuse, psychiatric hospitalization, and substandard income than either asthenic somatizers or non-somatizers. Asthenic somatizers had a higher risk of divorce than either diversiform somatizers or non-somatizers. Men with prominent somatization had an excess of psychiatric treatment for alcoholism or anxiety disorders, but, unlike female somatizers, no excess of criminality. These clinical differences suggest that the psychiatric processes associated with somatization may be qualitatively different in men and women. The method used here is generally applicable in genetic epidemiology to identify natural clinical subtypes within a heterogeneous phenotype. 相似文献
1000.