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101.
A series of 5-aminomethinimino-3-methyl-4-isoxazolecarboxylic acid phenylamides 4 has been prepared by condensation of 5-amino-3-methyl-4-isoxazolecarboxylic acid phenylamides 1 with trichloroacetic aldehyde. Alcoholysis of trichloro derivatives 2 gave 5-alkoxymethine derivatives 3 which, on reaction with an appropriate amine, formed the corresponding compounds 4 . The compounds obtained were evaluated for their immunological activity. The properties of three compounds, described in this report, permitted inhibition of the immune response in all possible ways: diminishing both types of immune response ( 4d ), humoral immune response ( 4a ), or cellular immune response ( 4c ). Preparation 4d is comparable in its effectiveness to CsA, so it may be potentially used as an agent for prolongation of the function of transplanted organs. Two other compounds may potentially be used in cases where only one type the immune response is required for combating pathogen invasion.  相似文献   
102.
采用四氮唑蓝(MTT)比色法检测TSH存在和缺乏时白细胞介素1α(IL-1α)对鼠FRTL-5细胞增殖的影响。结果提示,在无TSH条件下IL-1α20~2000kU/L对FRTL-5细胞无明显促增殖作用;在TSH存在时IL-1α20和200kU/L对FRTL-5细胞增殖亦无明显抑制作用,IL-1α2000kU/L则可显著抑制TSH介导的FRTL-5细胞增殖。  相似文献   
103.
104.
We report a patient with eosinophilia accompanied by Hodgkin's disease who showed remarkable increase in granulocyte-macrophage colony-stimulating factor (GM-CSF) in plasma but no increase in interleukin-5 (IL-5). The plasma GM-CSF level normalized as eosinophilia and lymphadenopathy disappeared after chemotherapy. Immunohistochemical study with immunoperoxidase staining technique showed a positive stain in lymph node cells by monoclonal anti-GM-CSF antibody. Eosinophilia is often accompanied by Hodgkin's disease, and several cases have been reported to show high levels of plasma IL-5. To our knowledge, this is the first report to show a high level of plasma GM-CSF in Hodgkin's disease with eosinophilia.  相似文献   
105.
以环己酮为起始原料,经与苯肼缩合、氧化、Mannich 反应制得1,2,3,9-四氢-3-二甲胺基甲基-4H-咔唑-4-酮盐酸盐(5),后者再与2-甲基咪唑缩合、甲基化合成翁丹西隆,总收率为10.4%。  相似文献   
106.
The content of serotonin (5-HT), 5-hydroxyindoleacetic acid (5-HIAA) and norepinephrine (NE) was analysed in 71 human spinal cords obtained post-mortem. The highest content of 5-HT, 5-HIAA and NE was found in the lumbar enlargement of the spinal cord. 5-HT and 5-HIAA content increased from fetal to adult spinal cord whereas the content of NE decreased. Characteristic segmental distribution of measured monoamines was present in adult spinal cord only. In two patients spinal cord lesion led to the reduction in spinal cord content of 5-HT, 5-HIAA and NE and loss of characteristic segmental distribution of these substances. These results are in general agreement with observations on spinal cord of different animal species.  相似文献   
107.
In rabbit platelet rich plasma (PRP), 5-hydroxytraptamine (5-HT,0.03~3μmol/L) induced decrease in light transmission (DLT) dose-de pendently with centralization, as revealed by electron microscopy. However, 5-HT did not induced platelet aggregation and release reaction. 5-HT-induced DLT was inhibited by methysergide (0.3~30μmol/L), indomethacin (0.3~10μmol/L) and PGE_1 (0.01~0.3μmol/L) in a dose-dependent manner, but not EGTA(0.3~3mmol/L). Collagen(Coll), arachidonic acid (AA), adenosine diphosphate (ADP) and a stable thromboxane A2 analoge(STA_2) also induced DLT before aggregation by themselves, which was also inhibited by PGE_1, but not inhibited by EGTA except for Coll However,Coll-, AA-, STA_2-and ADP-induced DLT were reduced by pretreatment of PRP with 5-HT dose-depen-dently. The duration of DLT by Coll and AA were decreased from 151.4±5.93 sec and 15(?)38±0.60sec to 45.44±4.04 sec and 9.00±1.25 sec respectively ((?)±s(?) P<0.01), but not by ADP and STA_2, 3μmol/L of ADP-and 0.3μmol/L of STA_2-induced aggregation which was not accompanied with release reaction were enhanced by 5-HT pretreatment, but in those (Coil 5μg/ml, AA 100~200μmol/L and STA_2 1~3 μmol/L) with release reaction, the amount of adenosine triphosphate(ATP)were suppressed significantly (P<0.001) by 5-HT pretreatment without the effect on the magnitude of aggregation, The mobilization of cytosolic free calcium concentration ([Ca~(2+)]i) was observed after 5-HT treatment in single washed platelet, the results indicated that the basic level of [Ca~(2+)] i was 64.78±3.24nmol/L and this level was increased dose-dependently and significantly at 30 sec after administration of 5-HT and the time of peak value of [Ca~(2+)] i was at 90~100 sec.The similar time courses of suppression of ATP released during aggregation, in cases of Coll(5μg/ml), AA (200μmol/L) and STA_2(3μmol/L), by 5-HT were also found in the present experiment.  相似文献   
108.
With the method of rapid gel sequencing, the complete nueleotide sequence of Fasciolopsis buski 5S rRNA has been determined: AAC GGG AUG AAG CUA GAC AUG UGG CGG CCU AGU UGG AGG UCG GAA CUC GGA AGU UAA GGA AUG UUG GGC CUG GUU AGU ACU GGU AUG GGU GAC CUU GGG AAU ACC GGG UGU UGC GUC CA_(OH) This have been compared with 553 species of other organisms 5S rRNA sequences previously published and fitted to a secondary structural model.  相似文献   
109.
This study examined the effect of acute and chronic administration of the selective 5-HT3 receptor antagonist BRL 46470A, an analog of granisetron, on the number of spontaneously active dopamine (DA) cells in the substantia nigra pars compacta (A9 or SNC) and the ventral tegmental area (A10 or VTA) in the rat. In the A10 area, the acute administration of BRL 46470A decreased the number of spontaneously active DA cells at a dose of 0.1 mg/kg (0.28 μmol/kg) ip, yet increased the number of spontaneously active DA cells at a dose of 0.3 mg/kg (0.84 μmol/kg). The chronic administration (21 days) of BRL 46470A appeared to produce a multiphasic dose-response curve. Thus, the chronic treatment with BRL 46470A increased the number of spontaneously active A10 DA cells at 0.03 (0.084 μmol) and 0.3 mg/kg, but decreased the number of spontaneously active A10 DA cells at a dose of 0.1 mg/kg. In contrast, BRL 46470A did not decrease the number of spontaneously active A9 DA cells after either acute or chronic administration (0.01-0.3 mg/kg). However, BRL 46470A did increase the number of spontaneously active A9 DA cells at acute and chronic doses similar to those that were effective in A10. The iv administration of (+)-apomorphine (APO) not only failed to reverse the decrease produced by chronic administration of BRL 46470A at 0.1 mg/kg, but further decreased the number of spontaneously active A10 DA cells. Similar to the results obtained with granisetron, the pretreatment of naive rats with either 0.01 or 0.1 mg/kg iv of BRL 46470A significantly potentiated (2-fold) the suppressant action of APO on the basal firing rate of A10, but not A9 DA cells. Overall, our results indicate that similar to granisetron, chronic BRL 46470A at 0.1 mg/kg selectively decreases the number of spontaneously active A10 DA cells, via a mechanism not related to depolarization inactivation. Presently, it is not clear what factors may contribute to the multiphasic dose-response curve of BRL 46470A. © 1994 Wiley-Liss, Inc.  相似文献   
110.
Medifoxamine, an antidepressant agent which has an original chemical structure, has been shown through in vitro studies, utilising radioligand binding in tissue homogenates, to bind with moderately high affinity to 5-HT1c and 5-HT2 receptor subtypes and to 5-HT uptake sites (IC50 950, 980, and 1,500 nM, respectively). It has been shown to bind in vivo to rat brain 5-HT2 receptors after acute treatment with high dose (50 mg/kg, i.e., 133.9 μmol/kg). After 14 days continuous treatment with low dose (20 mg/kg, 53.6 μmol/kg), a decrease in the capacity of [3H]-5-HT uptake and a dose-dependent down-regulation of 5-HT2 receptors in rat cerebral cortex were observed. These results indicate that medifoxamine, which has been shown previously to act through dopaminergic systems, interacts also with central serotonergic neurotransmission and particularly with the 5-HT2 receptors, which could contribute to its antidepressant effect.  相似文献   
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