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1.
The synthesis of N-substituted 4,5(3)-diphenyl-3(5)-pyrazoleamines by reaction of N-substituted 3-oxo-2,3-diphenylpropane-carbothioamides with hydrazine is described. Some compounds showed remarkable antipyretic, antiarrhythmic and hypotensive activity in rats, as well as weak antiinflammatory, analgesic and in vitro platelet antiaggregating activity.  相似文献   

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(Y1-a, Gda)3-x(Al1-b, Gab)5O12∶Ce3 x was synthesized by high-temperature solid state reaction in reducing atmosphere based on high purity raw materials. The influences of Y3 , Gd3 , Al3 , Ga3 and activator-Ce3 on the performance of the phosphor were investigated. Ce3 is the luminescent center and activates the phosphor after it replaces Y partially. When x is less than 0.12, the volume of the crystal and the emission intensity of the phosphor increase with the quantity of Ce3 . When CeO2 is added too much, the phase CeAlO3 will appear. The excitation and emission peaks of the phosphor will shift to longer wavelength when the amount of Gd3 increases. The wavelength of the emission peak can shift about 20 nm when a equals 0.45. In opposite, the excitation and emission peaks will shift to shorter wavelength, when part of Al3 is replaced by Ga3 . The wavelength of the emission peak can shift about 20 nm when b equals 0.55. Through the replacemeat of Y3 or Al3 by Gd3 or Ga3 , the emission peak of the phosphor can be adjusted from 520 to 560 nm. In this way, the phosphor is more suitable for different chips.  相似文献   

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Structural modifications requiring novel synthetic chemistry were made to the morpholine acetal human neurokinin-1 (hNK-1) receptor antagonist 4, and this resulted in the discovery of 2-(R)-(1-(R)-3, 5-bis(trifluoromethyl)phenylethoxy)-3-(S)-(4-fluoro)phenyl-4-(3-ox o-1 ,2,4-triazol-5-yl)methyl morpholine (17). This modified compound is a potent, long-acting hNK-1 receptor antagonist as evidenced by its ability to displace [125I]Substance P from hNK-1 receptors stably expressed in CHO cells (IC50 = 0.09 +/- 0.06 nM) and by the measurement of the rates of association (k1 = 2.8 +/- 1.1 x 10(8) M-1 min-1) and dissociation (k-1 = 0.0054 +/- 0.003 min-1) of 17 from hNK-1 expressed in Sf9 membranes which yields Kd = 19 +/- 12 pM and a t1/2 for receptor occupancy equal to 154 +/- 75 min. Inflammation in the guinea pig induced by a resiniferatoxin challenge (with NK-1 receptor activation mediating the subsequent increase in vascular permeability) is inhibited in a dose-dependent manner by the oral preadmininstration of 17 (IC50 (1 h) = 0.008 mg/kg; IC90 (24 h) = 1.8 mg/kg), indicating that this compound has good oral bioavailbility and peripheral duration of action. Central hNK-1 receptor stimulation is also inhibited by the systemic preadministration of 17 as shown by its ability to block an NK-1 agonist-induced foot tapping response in gerbils (IC50 (4 h) = 0.04 +/- 0.006 mg/kg; IC50 (24 h) = 0.33 +/- 0.017 mg/kg) and by its antiemetic actions in the ferret against cisplatin challenge. The activity of 17 at extended time points in these preclinical animal models sets it apart from earlier morpholine antagonists (such as 4), and the piperidine antagonists 2 and 3 and could prove to be an advantage in the treatment of chronic disorders related to the actions of Substance P. In part on the basis of these data, 17 has been identified as a potential clinical candidate for the treatment of peripheral pain, migraine, chemotherapy-induced emesis, and various psychiatric disorders.  相似文献   

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Highly specific antibodies against 3,3',5'-triiodothyronine (reverse T3, R-T3) have been produced in rabbits. The crossreaction with T4 is about 0.05%. A radioimmunoassay for R-T3 in unextracted serum was developed. ANS is used for blocking the binding of tracer and endogenous R-T3 to TBG. The sensitivity to the assay is 0.06 ng/ml plasma. The mean normal R-T3 concentration is 0.20 ng/ml. Thyrotoxic patients show elevated levels; in most hypothyroid patients R-T3 concentrations are below the detection limit.  相似文献   

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Separation of Tb~(3 ) , Dy~(3 ) , Ho~(3 ) , Er~( 3 ) with Solvent Impregnated Resins Containing Di-(2,4,4-trimethylpentyl) Phosphinic Acid  相似文献   

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The Y3(AI,Ga)_5O_(12):Ce~(3+),Cr~(3+),Nd~(3+)(YAGG) nano-phosphors with homogeneous particle-size distribution,low aggregation and average crystalline size of about 65 nm were obtained using a modified Pechini method.Only slight aggregation of the crystallites occurs after post-annealing at 1100℃.The intense Ce~(3+)bands in the excitation spectra of the Ce~(3+),Cr~(3+),Nd~(3+)co-doped materials monitoring the Cr~(3+) emission at 690 nm indicate energy transfer from Ce~(3+) to Cr~(3+).Weak Nd~(3+) lines are observed,as well.In addition,the emission of Nd~(3+)at 1060 nm with excitation of Ce~(3+) and Cr~(3+) confirms the Ce~(3+)/Cr~(3+)to Nd~(3+)energy transfer.The short average luminescence decay times for the Ce~(3+) emission indicate the Ce~(3+)/Cr~(3+)to Nd~(3+)energy transfer.Eventually,the Y_3(AI,Ga)_5O_(12):Ce~(3+),Cr~(3+),Nd~(3+) nano-phosphors exhibit persistent luminescence originating from the 4f~3→4f~3 transitions of Nd~(3+) which matches well to the first biological window to be used in bioimaging applications.  相似文献   

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In order to estimate the relative magnitude of the two alternative pathways of monodeiodination of thyroxine (T4) in adult humans, the metabolic clearance rates (MCR) and production rates (PR) of 3,3',5'-triiodothyronine (reverse-T3,rT3) and of 3,5,3'-triiodothyronine (T3) were determined in six euthyroid control subjects (C) and in five hypothyroid patients (H) receiving L-T4 as replacement therapy (0.15-0.3 mg/day). MCR was computed by a non-compartmental method of analysis from the plasma disappearance of 125I rT3 and 131I T3 during 72 h following simultaneous injection of tracers. PR was calculated from MCR and the serum concentration of rT3 and T3, respectively, determined by radioimmunoassay. In the H subjects, rT3 MCR averaged 97.1 +/- 12.8 (SD) 1/day and rT3 PR, 34.3 +/- 12.8 microng/day; T3 MCR was 28.7 +/- 6.1 1/day and T3 PR, 20.3 +/- 6.6 microng/day (all corrected to 70 kg body weight). These results were not significantly different from those in the control group; rT3 MCR 104 +/- 24 1/day, rT3 PR 33.0 +/- 9.2 microng/day; T3 MCR 24.0 +/- 5.9, T3 PR 24.2 +/- 4.1. The proportionof total triiodothyronine (rT3 averaged 62% in H patients and was similar (57%) in the C group. The results obtained in the H subjects indicate that the production of rT3 is a major route of T4 metabolism, equal to or exceeding that of T3. From the close agreement between the mean values for rT3 PR in the C and H groups it is concluded that most, if not all of the rT3 produced in normal humans is derived by extrathyroidal conversion from T4.  相似文献   

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The in-vivo biodistribution and pharmacokinetics in mice of 3'-azido-2',3'-dideoxythymidine (1, AZT), 2-bromomyristic acid (2) and their common prodrug, (+/-)-3'-azido-2',3'-dideoxy-5'-O-(2-bromomyristoyl)thymidine (3) are reported. The objectives of the work were to enhance the anti-human immunodeficiency virus and anti-fungal effects of 1 and 2 by improving their delivery to the brain and liver. The pharmacokinetics of AZT (beta t1/2 (elimination, or beta-phase, half-life) = 112.5 min; AUC (area under the plot of concentration against time) = 29.1 +/- 2.9 micromol g(-1) min; CL (blood clearance) = 10.5 +/- 1.1 mL min(-1) kg(-1)) and its ester prodrug (3, beta t1/2 = 428.5 min; AUC = 17.3 +/- 4.7 micromol g(-1) min; CL = 17.6 +/- 4.8 mL min(-1) kg(-1) were compared after intravenous injection of equimolar doses (0.3 mmol kg(-1)) via the tail vein of Balb/c mice (25-30 g). The prodrug was rapidly converted to AZT in-vivo, but plasma levels of AZT (peak concentration 0.17 micromol g(-1)) and AUC (12.3 micromol min g(-1)) were lower than observed after AZT administration (peak concentration 0.36 micromol g(-1); AUC 29.1 micromol min g(-1). The prodrug also accumulated rapidly in the liver immediately after injection, resulting in higher concentrations of AZT than observed after administration of AZT itself (respective peak concentrations 1.11 and 0.81 micromol g(-1); respective AUCs 42.5 and 12.7 micromol min g(-1)). Compared with doses of AZT itself, 3 also led to significantly higher brain concentration of AZT (25.7 compared with 9.8 nmol g(-1)) and AUCs (2.8 compared with 1.4 micromol min g(-1)). At the doses used in this study the antifungal agent 2-bromomyristic acid was measurable in plasma and brain within only 2 min of injection. Hepatic concentrations of 2-bromomyristic acid were higher for at least 2 h after dosing with 3 than after dosing with the acid itself. In summary, comparative biodistribution studies of AZT and its prodrug showed that the prodrug led to higher concentrations of AZT in the brain and liver. Although the prodrug did not result in measurably different concentrations of 2-bromomyristic acid in the blood and brain, it did lead to levels in the liver which were higher than those achieved by dosing with the acid itself.  相似文献   

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Sexually receptive, intact, proestrous rats were infused bilaterally into the ventromedial nucleus of the hypothalamus with one of several serotonin (5-HT) agonists and with the endogenous ligand, 5-HT. Serotonin (2000 ng) and the 5-HT1A agonists, 8-hydroxy-2-(di-n-propylamino)tetralin [8-OH-DPAT (200 ng)], 5-methoxy-3-(di-n-propylamino)chroman [5-MEO-DPAC (200-2000 ng)] and 5-hydroxy-3-(N-di-n-propylamino)chroman [5-OH-DPAC (200-2000 ng)] inhibited female lordosis behavior within 10 min of the infusion. The rank order of the effectiveness of these compounds was 8-OH-DPAT > 5-OH-DPAC > or = 5-MEO-DPAC > 5-HT. The nonselective 5-HT agonist, 1-(m-trifluoromethyl) piperazine [TFMPP (2000 ng)], did not reduce lordosis behavior. In addition to their reduction of lordosis behavior, the 5-HT1A agonists elicited resistive behavior toward the male's attempts to mount. There were minimal effects of the 5-HT1A agonists on either quality of the lordosis reflex or on proceptivity. However, rats pretreated with TFMPP and infused with 8-OH-DPAT 1 hr later, did show a transient suppression of lordosis quality. These results provide further evidence that the ventromedial nucleus of the hypothalamus contains 5-HT1A sites, the activation of which reduces lordosis behavior in regularly cycling, proestrous rats.  相似文献   

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合成并鉴定了一种新的三氮烯试剂1-(2-苯并噻唑) -3-(3,5-二溴吡啶)-三氮烯(BTPyBT),考察了酸度、缓冲溶液用量、铜离子浓度、试剂用量、反应温度及反应时间等影响该试剂与铜发生荧光反应的条件,建立了一个测定铜的荧光分析方法。实验表明,在pH 9.16的硼砂-氢氧化钠缓冲液中,BTPyBT与铜离子在室温下反应20 min后可形成组成比为3∶1的稳定络合物。所建立铜的荧光分析方法的线性范围为0.5~80.0 μg/L,检出限为0.2 μg/L。方法应用于矿泉水、纯净水及河水等水样品中痕量铜的测定,测定结果与原子吸收光谱法一致,相对标准偏差(n=6)为1.2%~4.7%。  相似文献   

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The present study was designed to determine if frequency of repetitive photic stimulation could affect the response rate of an operant upon which such stimulation was made contingent. To test this hypothesis, we trained retarded and autistic children, equated for mental age, to pull a lever to obtain photic stimulation of different frequencies. It was found that (a) response rates of autistic children were related to the frequency of stimulation, while retarded children showed no such consistency. (b) The two groups did not differ in the average duration of time they engaged in stereotypies. (c) During a subsequent extinction session, two autistic children ceased responding, but one of two retarded children did not. (d) Noncontingent photic stimulation suppressed a food-motivated operant in one autistic child. These results were interpreted as evidence for frequency-dependent properties of repetitive visual feedback in autistic children. In addition, support was given to the position that performance deficits in autistic children correlating with the occurrence of stereotypies result from competition of different sources of reinforcement.  相似文献   

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