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1.
李腾 《首钢科技》2003,(5):23-24,36
阐述了RS-485总线规范,结合实例介绍了RS-485总线和智能累积仪的通讯解决方式;能源数据在关系数据库上的存储统计;自动抄量数据的自动报量功能。  相似文献   

2.
文章论述了基于RS-485总线的数据采集系统通信协议的设计与实现,本协议简单有效,经过工业现场测试,达到了设计要求.  相似文献   

3.
岳发强  胡乃联  宋鑫  陈玉民 《黄金》2007,28(12):33-35
基于ADAM-4000的RS-485总线结构,应用VC 和OpenGL,建立了黄金矿山生产调度模拟系统,模拟显示矿山各主要生产环节与主要设备状态.文中介绍了系统总体结构、ADAM模块、RS-485总线通讯方式和关键软件实现等系统主要组成部分.系统在矿山应用后,取得了满意的效果.  相似文献   

4.
针对企业电量自动采集的要求,使用计算机和RS-485总线技术实现了电量数据的自动采集、存储、监视、统计和制表等功能,为企业电能安全、经济、高效的运转提供了重要的数据依据。  相似文献   

5.
控制技术、计算机技术和网络技术相结合促进了集散控制系统(DCS)的进一步发展,使控制系统实现了集中管理、分散控制.本文以一个基于RS-485总线的温度、湿度控制系统为例,全面介绍了该系统的硬件组成及软件结构,并对通信过程中使用的Modbus协议进行说明.  相似文献   

6.
分析了AT89C2051单片机和西门子S7-200PLC串行通信接口的特性,介绍了PLC与单片机进行串行通信的实现方法,并给出了用于电焊机控制系统的以AT89C2051单片机为核心,输出信号通过RS-485总线与西门子S7-200PLC通信的应用实例.实际应用表明,该设计可靠性高,便于二次开发.  相似文献   

7.
本文对常用的几种串行接口-RS-232C、RS-422、RS-423做了对比分析,重点介绍了应用国内、外的集成电路芯片组成RS-422接口的方法,及其在工业控制中的应用实例。  相似文献   

8.
为了能及时、方便地掌握直流电弧炉循环水系统温度的变化情况,提出了采用PT100热电阻温度传感器结合高性能的ARM Cortex-M3微控制器和PC机实现分布式温度巡检报警的方案。为此,设计了以MB9AF116N微控制器为核心的高精度多路温度采集与报警模块,该模块采用JRM12864图形液晶动态显示采集到的数据和IO状态,通过按键或监控主机可设置报警启动延时时间以及可编程触点的动作方式。采用RS-485总线和ModbusRUT通信协议与监控主机通信,实现数据上传,同时可以接收主机下传的数据和控制信息。计算机监控程序采用LabWindows CVI开发平台,实现了对多个采集模块的集中监控。  相似文献   

9.
AS-i总线已广泛应用于多种行业,但在国内选矿厂应用较少。介绍了AS-i总线系统的体系结构,并通过实例阐述了AS-i总线在国外某大型浮选厂的应用,满足了现场控制要求,同时AS-i总线系统安全可靠,施工简单,并具有良好的开放性和可扩展能力。  相似文献   

10.
本文介绍了CAN总线在铝电解控制系统中的应用。叙述了基于CAN总线的系统结构、组成及特点。介绍了CAN总线通讯接口软件设计方案,用CAN总线解决了过去BITBUS控制系统中存在的不足之处。  相似文献   

11.
Highly lipophilic antitumor agent, palmitoyl rhizoxin (RS-1541), was incorporated into stable lipid emulsions about 100-1000nm in mean diameter consisting of triglyceride ODO and surfactant HCO-60. The pharmacokinetics of RS-1541 were studied after i.v. injection in mice, rats, rabbits, and dogs. Dog showed characteristic pharmacokinetics of RS-1541, compared with other species. RS-1541 was much more rapidly eliminated from plasma with emulsion particles in dogs than in mice, rats, and rabbits. Most amounts of injected RS-1541 were recovered in the liver six hours after administration to dogs, while less than 20% recoveries were observed for mice and rats. To clarify this species variation, opsonization of emulsion particles were evaluated. When emulsions (about 200nm in size) were opsonized by dog plasma, and intravenously injected to rats, total clearance and liver uptake of RS-1541 were increased to 1.8 fold and 2.7 fold of control values, respectively. In contrasts, emulsions opsonized by mouse, rabbit and human plasma did not show such drastic changes in pharmacokinetics of RS-1541 in rats. Furthermore, total clearance of RS-1541 for emulsions opsonized by dog plasma was increased to 1.9 fold of controls after injection to rabbits. These results indicate that opsonizing activities of dog plasma for RS-1541 emulsions are high, compared with other species. This species variation in opsonizing process probably caused the species variation in the pharmacokinetics of RS-1541 incorporated in lipid emulsions.  相似文献   

12.
13.
We evaluated the safety and efficacy of RS-25259, a potent and long-acting selective 5-HT3 receptor antagonist, for the prevention of postoperative nausea and vomiting (PONV) in women undergoing hysterectomy procedures. In this randomized, double-blind, placebo controlled, dose-ranging study, 218 healthy, consenting women were assigned to one of the six treatment groups: placebo or RS-25259 0.1, 0.3, 1.0, 3.0, or 30 microg/kg. All patients underwent a standardized general anesthetic technique. The study medication was administered i.v. 20-30 min before the end of surgery. During the initial 24-h period after surgery, the incidence of vomiting, the need for rescue antiemetics, the time to the first episode of emesis, and administration of rescue antiemetic medication, as well as a nausea visual analog scale and verbal categorical scale scores were recorded. In addition, recovery times from the end of anesthesia and the incidences of perioperative side effects were noted. Only 30 microg/kg RS-25259 significantly decreased the incidence of vomiting and the requirement for rescue antiemetics. The largest dose of RS-25259 also delayed the time to the first emetic episode and reduced the number of treatment failures. However, no differences were found in the severity of postoperative nausea (versus saline), and postoperative headaches were more common after the administration of RS-25259 0.3-30 microg/kg i.v. In conclusion, RS-25259 30 microg/kg i.v. was effective in reducing the incidence of PONV after major gynecologic surgery, but the occurrence of headaches with the larger doses of RS-25259 is a concern. Implications: RS-25259, a long-acting 5-HT3 antagonist, was effective in reducing postoperative vomiting only at the largest dose studied (30 microg/kg). However, RS-25259 had no antinausea activity, and the larger doses were associated with an increased incidence of headaches in the postoperative period.  相似文献   

14.
Cooperation in the action of agonists suggests that there are multiple binding sites on 5-hydroxytryptamine3 (5-HT3) receptors. The purpose of this study was to characterize these binding sites and their interactions on both native and cloned 5-HT3 receptors. The affinities of competitive 5-HT3 receptor antagonists were similar regardless of whether the receptors were labeled with [3H]RS-42358, [3H]granisetron, or 1-(m-[3H]chlorophenyl)biguanide ([3H]mCPG). By contrast, the affinities of the agonists 5-HT, mCPG, and phenylbiguanide were approximately 10-fold higher when the receptors were labeled with [3H]mCPG. The dissociation of [3H]mCPG, [3H]RS-42358, and [3H]RS-25259, but not [3H]granisetron, from both cloned and native 5-HT3 receptors was markedly slower in the presence of 5-HT or 2-methyl-5-HT than in the presence of antagonists such as RS-42358. This suggests that the binding of these agonists to unoccupied sites on the receptor can increase the receptor's affinity for prebound ligands and thereby slow their dissociation. These data support previous indications of positive cooperation among multiple binding sites on both native and cloned 5-HT3 receptors, and they extend this idea by demonstrating that agonists can modify the interaction of some, but not all, antagonists with the receptor.  相似文献   

15.
Inadequate vascularization and microvascular rejection are major limitations for successful free pancreatic islet xenotransplantation. Commonly used immunosuppressive regimens may alter the process of vascularization, and are ineffective at preventing graft rejection. In this study, we investigated, in vivo, the action of the new immunosuppressive agent RS-61443 on angiogenesis and microvascular rejection of rat pancreatic islets after xenogeneic transplantation into the dorsal skinfold of Syrian golden hamsters. In nontreated xenografts, intravital fluorescence microscopy demonstrated a regular process of vascularization during the first 6 days after transplantation. On days 10, 14, and 20, graft rejection was observed, characterized by microvascular leukocyte accumulation (244+/-59 mm(-2)), loss of endothelial integrity, and capillary perfusion failure. Islet xenografts of animals treated with RS-61443 (40 mg/kg per day) demonstrated inhibition of vascularization with the consequence of a markedly reduced size of the grafts' microvascular network (0.05+/-0.007 mm2), when compared with that of nontreated xenografts (0.09+/-0.015 mm2; P< 0.05). However, treatment with RS-61443 effectively prevented microvascular graft rejection, as indicated by the absence of leukocyte accumulation (24+/-9 mm(-2); P<0.01), endothelial damage, and nutritive perfusion failure. Thus, RS-61443 treatment may represent an interesting approach for improving the outcome of pancreatic islet xenotransplantation.  相似文献   

16.
Racemic oxybutynin (CAS 1508-65-2) is used clinically to treat urinary incontinence and reportedly undergoes N-deethylation to metabolites R- and/or S-desethyloxybutynin. To assess the role of these metabolites in the therapeutic effects of oxybutynin, the antimuscarinic and antispasmodic effects of RS-, R- and S-oxybutynin, RS-, R- and S-desethyloxybutynin and, for comparative purposes, RS-terodiline (CAS 7082-21-5) on isolated strips of guinea pig bladder, were examined. All of these compounds exhibited antimuscarinic activity: they competitively antagonized carbachol-induced contractions, with mean pA2 values (+/- S.E.) of 8.91 +/- 0.20, 8.80 +/- 0.27, 7.09 +/- 0.13, 8.55 +/- 0.32, 9.04 +/- 0.32, 7.31 +/- 0.35 and 6.77 +/- 0.22, respectively. Consistent with an antispasmodic action, all of the compounds produced similar inhibition of potassium-induced contraction; the mean IC50 values for reducing responses to 137.7 mmol/l potassium were between 2.22 and 5.68 mumol/l. Thus, RS- and R-oxybutynin and RS- and R-desethyloxybutynin exhibited high antimuscarinic activity relative to their antispasmodic activity, while S-oxybutynin, S-desethyloxybutynin and RS-terodiline exhibited relatively weak antimuscarinic activity. It is concluded that deethylation of oxybutynin to desethyloxybutynin does not appreciably alter its antimuscarinic or antispasmodic activity and that R- and/or S-desethyloxybutynin probably contribute significantly to the pharmacological properties of oxybutynin in humans. In addition, since the relative potency of the antimuscarinic-to-antispasmodic actions of S-oxybutynin was equivalent to that of RS-terodiline, S-oxybutynin deserves consideration for development as a single-enantiomer drug for the treatment of urinary incontinence. It may produce the same beneficial therapeutic effects as both RS-terodiline and RS-oxybutynin but, like RS-terodiline, produce a lower incidence of antimuscarinic side-effects than seen with RS-oxybutynin.  相似文献   

17.
The 5-HT2C receptor is one of three closely related receptor subtypes in the 5-HT2 receptor family. 5-HT2A and 5-HT2B selective antagonists have been described. However, no 5-HT2C selective antagonists have yet been disclosed. As part of an effort to further explore the function of 5-HT2C receptors, we have developed a selective 5-HT2C receptor antagonist, RS-102221 (a benzenesulfonamide of 8-[5-(5-amino-2,4-dimethoxyphenyl) 5-oxopentyl]-1,3,8-triazaspiro[4.5]decane-2,4-dione). This compound exhibited nanomolar affinity for human (pKi = 8.4) and rat (pKi = 8.5) 5-HT2C receptors. The compound also demonstrated nearly 100-fold selectivity for the 5-HT2C receptor as compared to the 5-HT2A and 5-HT2B receptors. RS-102221 acted as an antagonist in a cell-based microphysiometry functional assay (pA2 = 8.1) and had no detectable intrinsic efficacy. Consistent with its action as a 5-HT2C receptor antagonist, daily dosing with RS-102221 (2 mg/kg intraperitoneal) increased food-intake and weight-gain in rats. Surprisingly, RS-102221 failed to reverse the hypolocomotion induced by the 5-HT2 receptor agonist 1-(3-chlorophenyl)piperazine (m-CPP). It is concluded that RS-102221 is the first selective, high affinity 5-HT2C receptor antagonist to be described.  相似文献   

18.
介绍了一种基于RS-485通信技术和现场总线技术结合的全数字高炉冷却系统水温差及热流强度在线监测技术在南钢4号高炉的应用,包括系统组成、特点、功能等,并对该系统的应用情况进行了分析和总结。  相似文献   

19.
Four types of lipid emulsion for highly lipophilic antitumour agent RS-1541 (13-O-palmitoylrhizoxin) with mean particle diameters of 200-260 nm were prepared using soybean oil (SOY) or dioctanoyldecanoylglycerol (ODO) for the oil phase and lecithin (LEC) or polyoxyethylene-(60)-hydrogenated castor oil (HCO-60) for surfactants. The lipolysis rate of HCO-60-emulsified emulsions by lipoprotein lipase was much slower than that of LEC-emulsified emulsions. Particle sizes of emulsions incubated in plasma with the lipase for six hours were 75%, 79%, 101%, and 93% of initial values for SOY/LEC, ODO/LEC, SOY/HCO-60, and ODO/HCO-60 emulsions, respectively, showing an apparent size decrease for LEC-emulsified emulsions. In rats, uptake clearance values of SOY/LEC and ODO/LEC emulsions of RS-1541 in the reticuloendothelial system (RES) were 81.2 and 135.3 mL h(-1), respectively, and AUC values were 4.0 and 1.3 microg h mL(-1), respectively. In contrast, RES uptake clearances of HCO-60 emulsions of RS-1541 were considerably lower (4.2 mL h(-1) for SOY/HCO-60; 2.2 mL h(-1) for ODO/HCO-60), resulting in high AUC values (35.4 microg h mL(-1) for SOY/ HCO-60; 63.9 microg h mL(-1) for ODO/HCO-60). The concentrations of RS-1541 in tumour tissues after an intravenous administration of ODO/HCO-60 emulsions of RS-1541 to mice bearing solid tumour M5076 sarcoma were about ten times higher than those after the administration of SOY/LEC emulsions. These results indicate that HCO-60 emulsions, compared with conventional LEC emulsions, are more stable to lipoprotein lipase and show low uptakes by RES organs, long circulations in the plasma, and high distributions in tumours. Thus, these sterically stabilized emulsions could show potential as effective carriers for highly lipophilic antitumour agents to enhance the drug delivery in tumours.  相似文献   

20.
Activation of alpha 1-Adrenergic receptors via systemic administration of drugs such as phenylpropanolamine (PPA) and cirazoline results in the suppression of feeding in rats. Whether PPA acts via activation of the three currently identified alpha 1-Adrenoceptor subtypes is unknown. The intent of the present study was thus to examine the effects of systemic administration of the novel alpha 1a-Adrenoceptor antagonist RS-17053 on PPA-induced anorexia. Adult male rats (n = 6 to 8 per group) were pretreated (IP) with either 0, 0.1, 0.5, 2.5, or 10.0 mg/kg RS-17053 or with 2.0 mg/kg of the prototypical alpha 1-Adrenoceptor antagonist prazosin. Five minutes later, each rat was treated (IP) with either 0, 5, 10 or 15 mg/kg PPA. Food and water intakes were recorded for a 30 min period starting 10 min after the the treatment injection. Rats pretreated with vehicle and then treated with PPA exhibited a dose-dependent suppression of feeding with a maximal effect evident at the 15 mg/kg dose of PPA. Pretreatment with 2.0 mg/kg prazosin reversed the anorexic activity of PPA. Pretreatment with RS-17053 (0.1-2.5 mg/kg) did not alter either baseline feeding or the anorexic action of PPA. These results suggest that PPA does not act via the alpha 1a-Adrenergic receptor subtype to suppress food intake.  相似文献   

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