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采用知识点的方式组织知识资源,有利于知识的获取、分享、分配和存取.但是传统的树型结构对知识的整体关系描述能力不足,不利于分布式环境下对知识资源的查找和定位.语义网是一种可以详细描述本体间复杂关系并具有天然分布式特性的技术.然而一般的语义网本身不是按照知识点的方式进行组建.本文对语义网进行扩展,使其适用于描述基于知识点组织的知识资源.通过应用案例,按照知识点进行扩展的语义网可以有效地描述知识资源间的相互关系,便于知识的理解和利用,并且对知识的查找和定位也变得更加方便. 相似文献
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查询扩展技术通过向初始查询请求中加入相似或者相关的词,来减少查询请求与相关文献在表达上的不匹配现象,改善检索性能.本文利用语义单元的语义表达能力和语义单元之间的关系,将与初始查询具有密切语义关系的查询词或短语加入到初始查询请求中,更加全面地表示了用户的查询意愿.算法的时间复杂度为O(L),只与搜索请求的长度L有关,与语义单元表示库的规模无关,这对实时性要求较高的搜索引擎来讲是很实用的. 相似文献
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依据模型知识的特性,定义了模型描述本体和任务求解本体,为模型提供语义支持.模型语义分为描述语义和行为语义.基于描述语义的相似性判定,模型可进行潜在冲突预测;然后根据任务求解本体的定义,模型通过行为语义交互,进行行为协商;而在执行过程中,模型需要为每一个操作申请资源,因此模型根据模型描述本体和描述语义对资源申请进行协商,从而得到互不冲突的操作执行序列,消除冲突.最后通过实验分析验证算法的有效性. 相似文献
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曾小武 《中国现代应用药学》2004,(1):142-146
文章主要从微观角度对歇后语的语面和语底之间的语义关系进行考察 ,探讨二者之间语义关联方式的多样性 :从总体上可以分为词义关联和句义关联二类 ,其中又包含多个细节情形。试图通过揭示歇后语的微观语义关系 ,找寻歇后语语义生成的普遍原理 ,并通过这个原理从侧面解释歇后语趣味性的成因。 相似文献
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《Pharmacological reports : PR》2014,66(5):727-731
BackgroundA combination of phenylbutazone (PBZ) and ketoprofen (KP) is popular in therapy of rheumatoid arthritis (RA) but could be unsafe due to the uncontrolled growth of toxicity.MethodsQuenching fluorescence of serum albumin in the presence of the both drugs has been characterized by dynamic KQ [M−1], static V [M−1] quenching constants and also association constants Ka [M−1].ResultsThe quenching of tryptophanyl residues fluorescence by the KP and PBZ indicates the capability of these drugs to accept the energy from Trp-214 and Trp-135. Strong displacement of KP and PBZ bound to albumin cause by the binding of the second drug to SA close to Trp-214 (subdomain IIA) has been obtained. The displacement was also confirmed on the basis of quenching and association constants.ConclusionsThe conclusion, that both PBZ and KP form a binding site in the same subdomains (IIA or/and IB), points to the necessity of using a monitoring therapy owning to the possible increase of the uncontrolled toxic effects. 相似文献
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Objective To investigate the relationship between the consumption of antibacterial agents and resistance rate of Klebsiela pneumoniae(KP)in the hospital respiratory unit for 3 consecutive years in 2005-2007.Methods The total antibacterial consumption expressed as defined DDDs/100BD,as well as resistance rate of total KP and producing ESBLs KP were collected,and their correlation was analyzed.Results The rate of resistance of KP to cefoperazone/sulbactam,Cefepime,Imipenem,Moxifloxacin was significantly positively associated with the consumption of Cefotaxime,Ceftazidime,Moxifloxacin,Amikacin respectively;A significant positive association was observed between the rate of resistance of KP to Piperacillin/Tazobactam,Ceftriaxone and the consumption of Imipenem;The rate of resistance of KP to Piperacillin,Cefotaxime,Ciprofloxacin was significantly positively associated with the consumption of Levofloxacin.ESBLs producing bacilli of KP were detected in 44 of 75 isolates(58.7%),The rate of resistance of producing ESBLs KP to Piperacillin/Tazobactam,Ceftriaxone was significantly positively associated with the consumption of Imipenem,Ceftazidime;A significant positive association was observed between the rate of resistance of producing ESBLs KP to Piperacillin,Imipenem and the consumption of Moxifloxacin.There was no significant correlation in other drugs.Conclusions A relationship existed between antimicrobial consumption and rates of resistance of KP in the hospital respiratory unit.We must use antibiotics carefully and with reason to control and lessen the drug resistance of bacterial. 相似文献
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Nakao K Murata K Deguchi T Itoh K Fujita T Higashino M Yoshioka Y Matsumura S Tanaka R Shinada T Ohfune Y Matsuda H 《Biological & pharmaceutical bulletin》2011,34(7):1143-1146
Kaempferia parviflora (KP), a Zingiberaceae plant, is used as a folk medicine in Thailand for the treatment of various symptoms, including general pains, colic gastrointestinal disorders, and male impotence. In this study, the inhibitory activities of KP against xanthine oxidase (XOD) were investigated. The extract of KP rhizomes showed more potent inhibitory activity (38% at 500 μg/ml) than those of the other Zingiberaceae plants tested. Ten methoxyflavones were isolated from the KP extract as the major chemical components and their chemical structures were elucidated by X-ray crystallography. The structurally confirmed methoxyflavones were subjected to the XOD inhibitory test. Among them, 3,5,7,4',5'-pentamethoxyflavone and 3',4',5,7-tetramethoxyflavone showed inhibitory activities (IC(50) of 0.9 and >4 mM, respectively) and their modes of inhibition are clarified as competitive/non-competitive mixed type. To the best of our knowledge, this is the first report to present the inhibitory activities of KP, 3,5,7,4',5'-pentamethoxyflavone and 3',4',5,7-tetramethoxyflavone against XOD. 相似文献
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Coaccioli S 《European review for medical and pharmacological sciences》2011,15(8):943-949
Ketoprofen (KP), a nonsteroidal anti-inflammatory drug (NSAID), possesses analgesic, antipyretic and anti-inflammatory properties. Oral KP is widely used in musculoskeletal pain and inflammation in muscles and joints, including arthritis pain, osteoarthritis, stiffness of the joints, soft tissue rheumatism, and sports injuries. In common with all NSAIDs, oral KP has been associated with systemic adverse events and in particular gastrointestinal disorders. Topical application of the active ingredient is locally effective and at the same time minimises the risk of systemic adverse events. Pharmacokinetic studies show that serum levels of the active ingredient following topical KP 2.5% gel are less than 1% of those reported after oral dosing, thereby providing good levels of pain relief without the systemic adverse events normally associated with oral NSAIDs. In comparative studies, topical KP 2.5% gel twice daily showed clinical benefits in patients with a range of musculoskeletal conditions. KP 2.5% gel is generally well tolerated but the treated skin area should not be exposed to direct sunlight, including solarium (sunbeds), during the treatment and for 2 weeks afterwards as topical photosensitization has been reported. To our knowledge, this is the first overview on the use of topical KP (tKP) 2.5% gel which includes data from both clinical trials and from 'real-life' clinical practice. 相似文献
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目的探讨深圳市龙岗区常用抗菌药物用量与肺炎克雷伯菌耐药率的相关性。方法统计2005~2010年深圳市龙岗区5个二甲医院26种常用抗菌药物平均每日每百张床位所消耗的DDDs及各类标本培养的肺炎克雷伯菌的耐药率.并对抗菌药物用量与耐药率进行相关性分析。结果肺炎克雷伯菌对头孢唑啉、氨苄西林、头孢他啶、庆大霉素、妥布霉素、环丙沙星、左氧氟沙星、复方新诺明、阿米卡星、美岁培南的耐药率与部分抗生素的用量有正相关关系(P〈0.05)。结论肺炎克雷伯菌对部分抗菌药物耐药水平与部分常用抗菌药物用量之间存在正相关哭系。、临床必须加强抗菌药物的使用管理,规范应用抗生素。 相似文献
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Kisspeptins: a multifunctional peptide system with a role in reproduction, cancer and the cardiovascular system 总被引:2,自引:0,他引:2
Orphan G-protein-coupled receptors that have recently been paired with their cognate ligand are an often untapped resource for novel drug development. The KISS1 receptor (previously designated GPR54) has been paired with biologically active cleavage peptides of the KiSS-1 gene product, the kisspeptins (KP). The focus of this review is the emerging pharmacology and physiology of the KP. Genetic linkage analysis in humans revealed that mutations in KISS1 (GPR54, AXOR12 or hOT7T175) result in idiopathic hypogonadotrophic hypogonadism and knockout mouse studies confirmed this finding. Identification of KISS1 (GPR54) as a molecular switch for puberty subsequently led to the discovery that KP activate the GnRH cascade. Prior to the role of KISS1 (GPR54) in puberty being described, KP had been shown to be inhibitors of tumour metastasis across a range of cancers. Subsequently the mechanism of this inhibition has been suggested to be via altered cell motility and adhesiveness. PCR detected highest expression of KP and KISS1 (GPR54) in placenta, and changes in KP levels throughout pregnancy and expression in trophoblasts suggests a role in placentation. Placentation and metastasis are invasive processes that require angiogenesis. Investigation of KISS1 (GPR54) and KP in vasculature revealed discrete localisation of KISS1 (GPR54) to blood vessels prone to atherosclerosis and a potent vasoconstrictor action. A role for KP has also been shown in whole body homeostasis. KP are multifunctional peptides and further investigation is required to fully elucidate the complex pathways regulated by these peptides and how these pathways integrate in the whole body system. 相似文献
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Jennifer J Sheng Nehal A Kasim Ramachandran Chandrasekharan Gordon L Amidon 《European journal of pharmaceutical sciences》2006,29(3-4):306-314
This study investigated the combined effect of pH and surfactant on the solubility and dissolution of ketoprofen (KP), a highly permeable and an ionizable and water-poorly soluble drug in gastrointestinal tract. The equilibrium solubility of KP was determined in buffers at the pH range from 4.0 to 6.8 and sodium lauryl sulfate (SLS) concentrations from 0% to 2.0%. Its intrinsic dissolution rate was measured in the same media using a rotating disk apparatus. A simple additive model accounting for the free unionized KP and ionized KP(-) forms, and their corresponding micellar forms was employed to study the in vitro solubility and dissolution behavior. Non-linear regression analysis showed that the proposed model agreed well with the experimental data, with R(sq)=0.96 (P<0.0001) for the solubility study, and R(sq)=0.98 (P<0.0001) for the intrinsic dissolution rate measurement. The pK(a) and c(KP) values are estimated as 4.76+/-0.00 and 0.253+/-0.05 mg/mL, respectively, in good agreement with literature reports. The micellar solubilization coefficient k(*) for the unionized [KP](micelle) is 757+/-165 L/mol, whereas the value k(**) for the ionized [KP(-)](micelle) is 9.88+/-6.70 L/mol. The diffusion coefficients of various species: KP, KP(-), [KP](micelle), and [KP(-)](micelle), are 7.68 x 10(-6), 1.54 x 10(-6), 2.32 x 10(-7), and 2.13 x 10(-20)cm(2)/s, respectively. The maximum enhancement of solubilization is approximately 232-fold, while the maximum dissolution amplification is only 54-fold because of the smaller diffusivity of micellar species. The dramatic enhancement of in vitro solubility/dissolution attributable to an increase of pH and presence of SLS mimics the in vivo solubilization/dissolution behavior of KP along the gastrointestinal tract, when the pH increases from 1-2 in the stomach to 5-6 in the duodenum. The results suggest that the KP dissolves very rapidly in small intestine, implying that its absorption will be predominantly controlled by gastric emptying, and only minimally limited by the subsequent dissolution processes. This behavior is very similar to BCS I drugs, thus KP may be considered for possible waivers of bioequivalence. 相似文献
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目的 分析儿童肺炎克雷伯菌(Klebsiella pneumoniae,KP)感染的临床特征及耐药性,为预防和控制耐药的KP感染提供临床依据。方法 收集枣庄市妇幼保健院2019年1月至12月经细菌培养为KP感染的68例脓毒症儿童临床资料(男28例,女40例),按照KP耐药表型分为超广谱β-内酰胺酶(extended spectrum β-lactamases,ESBLs)阳性KP感染组、ESBLs阴性KP感染组,比较两组患儿预后、住院时间、治疗中使用抗生素级别、抗生素种类、机械通气等的差别。计数资料采用χ2检验或Fisher确切概率法,计量资料采用Mann-Whitney U检验。结果 ESBLs阳性KP感染组病死率高于ESBLs阴性KP感染组(3/23比0/45),住院时间长于ESBLs阴性KP感染组,使用抗生素种类多于ESBLs阴性KP感染组,使用碳青酶烯类率高于ESBLs阴性KP感染组,机械通气率高于ESBLs阴性KP感染组(均P<0.05);两组住院史及抗生素暴露差异均无统计学意义(均P>0.05)。结论 ESBLs阳性KP感染与预后呈负相关性。 相似文献
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An on-line, high-performance frontal analysis (HPFA)-high-performance liquid chromatographic system was developed for the enantioselective determination of a low level of unbound ketoprofen (KP) that is in equilibrium with KP that is bound to protein. The system consists of three subsystems (HPFA system, preconcentration system, and chiral separation system) connected in series in the stated order via column-switching valves. When either a 300-microL portion of buffer solution containing 300 or 550 microM human serum albumin and 100 or 300 microM racemic KP or a 300-microL portion of human plasma containing 12.5-100 microM racemic KP was directly injected onto the HPFA column with the mobile phase at a low flow rate, KP was separated from proteins and eluted as a zonal peak with a plateau. The KP concentration in the eluant of the plateau region was the same as the unbound-KP concentration that was in equilibrium with protein-bound KP in the initial sample solution. A 1-mL portion of the eluant of the plateau region was switched to the preconcentration system, where KP was adsorbed and condensed on an octadecylsilyl silica (ODS) column. The adsorbed KP was eluted out of the ODS column and transferred to the chiral separation system, via another switching valve, where the enantiomers of unbound KP were separated and determined. The results agree well with those obtained by the conventional ultrafiltration method.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Pectin-ketoprofen (PT-KP) prodrug with the potential for colon targeted delivery has been evaluated. A sensitive HPLC method was established for the determination of concentration of ketoprofen (KP) in rats. This method was also used to evaluate the colon targeting property of PT-KP. KP or PT-KP was given to rats by oral administration at a dosage of 10mg/kg. Plasma and the different parts of gastrointestinal (GI) tract were taken after 2, 4, 6, 8, 10 and 12h of oral administration of KP or PT-KP to rats and the concentration of KP was measured by HPLC. Preliminary experiments show KP distributes mainly in stomach, proximal small intestine and distal small intestine. However, KP released from PT-KP mainly distributes in cecum and colon. Therefore, this approach suggests that PT-KP prodrug has a good colon targeting property. 相似文献