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81.
Continually phytochemical study of the roots of Heracleum dissectum had led to the isolation of three previously undescribed polyacetylene glycosides ( 1 – 3 ), together with seven known compounds, including one polyacetylene ( 8 ) and six coumarins ( 4 – 7 and 9 – 10 ) using diverse chromatographic methods. The structures of these three new compounds were characterized and identified as deca‐4,6‐diyn‐1‐yl β‐d ‐glucopyranosyl‐(1→6)‐β‐d ‐glucopyranosyl‐(1→2)‐β‐d ‐glucopyranoside ( 1 ), (8Z)‐dec‐8‐ene‐4,6‐diyn‐1‐yl β‐d ‐glucopyranosyl‐(1→6)‐β‐d ‐glucopyranosyl‐(1→2)‐β‐d ‐glucopyranoside ( 2 ), and (8E)‐dec‐8‐ene‐4,6‐diyn‐1‐yl β‐d ‐glucopyranosyl‐(1→6)‐β‐d ‐glucopyranosyl‐(1→2)‐β‐d ‐glucopyranoside ( 3 ) based on their physicochemical properties and extensive analyses of various spectroscopic data. Their triglycerides accumulating activities were assayed and the results showed that the three new polyacetylene glycosides ( 1 – 3 ) exhibited triglyceride accumulating activities in 3T3‐L1 adipocytes.  相似文献   
82.
Sodium alendronate is the first in a pharmacological class known as bisphosphonates, used for treatment of various bone diseases. Assay of bisphosphonates by a spectroscopic technique is very challenging due to the fact that they lack chromophores and none of them are fluorescent. In this work, a simple method is presented for determination of alendronate in bulk and in pharmaceutical tablets using spectrofluorometry by exploiting the ability of alendronate to displace salicylate from the iron(III)–salicylate chelate, forming a non‐fluorescent colorless iron(III)–alendronate complex. The liberated salicylate is fluorescent and is equivalent to the mount of alendronate added. The response was linear over the concentration range 20–90 μM and the proposed method was validated according to the guidelines of the International Conference on Harmonization. The correlation coefficient was found to be 0.995 and the limit of detection was 7.5 μM. The method was successfully applied for determination of alendronate in the commercially available Osteonate® tablets. The average percent recovery ± percent relative standard deviation was found to be 102.118 ± 2.033 which is congruent with the label claim of the dosage form. The results were also compared to a reported method using t‐test and F‐test at 95% confidence level; no significant differences were observed. The presented method is simple, fast, easy, cost‐effective and suitable for routine pharmaceutical analysis.  相似文献   
83.
84.
The objective of this study is to establish a novel method for continuously monitoring thrombus progression with various outcome measures and to assess the efficacy of antithrombotic drugs in murine thrombosis model in mice. In the study, thrombus was induced in the femoral vein of mice by FeCl3 and monitored over time by spectral‐domain optical coherence tomography (OCT). Three‐dimensional images of thrombi with or without heparin as an antithrombotic agent were obtained from OCT angiography. In addition, several parameters of thrombi were analyzed and compared between control and anticoagulant groups. By using OCT, we were able to trace thrombus generation in the same mouse in real time. We found that in our model heparin reduced thrombus size by ~60% and thrombus cross‐sectional area by 50%. OCT results also show that both time to thrombus size (>0.02mm3) and time to occlusion (>30%) were significantly reduced after heparin addition. This study demonstrates that OCT reliably monitors thrombus generation and progression from various aspects including thrombus size. This enables us to measure the kinetic of thrombosis more accurately, and effectively evaluate the efficacy and activities of antithrombotic drugs. This model may represent a useful tool in antithrombotic drug discoveries in preclinical studies.   相似文献   
85.
肺隐球菌病41例临床分析   总被引:9,自引:0,他引:9  
目的总结分析41例肺隐球菌病患者的临床特点。方法回顾性分析我院(2003年1月~2006年10月)41例肺隐球菌病的临床、影像学表现,免疫学检查、病理及抗真菌治疗疗效。结果①41例肺隐球菌病,男28例,女13例,有基础疾病者18例,有临床症状者22例,影像学表现为结节肿块型27例,肺炎型8例,混合型6例。②有基础疾病的18例患者中有临床症状者15例;影像学表现为肺炎型8例,混合型4例,结节肿块型6例;并发隐球菌脑膜炎2例。无基础疾病患者23例,多无临床症状或临床症状较轻,多表现为结节肿块型(21例),无并发症,预后较好。③抗真菌药物治疗36例,治愈34例,好转2例(有效率100%)。都使用氟康唑治疗,疗程2周~2年不等。结论免疫功能正常的肺隐球菌病患者病变局限,多为结节肿块型,并发症少,预后好;免疫功能异常者多表现为肺炎型或混合型,易出现全身播散。肺隐球菌病单用氟康唑抗真菌治疗效果好,应为首选。  相似文献   
86.
Most peptide and protein drugs are short-lived species in vivo with a circulatory half-life of several minutes. This is particularly valid for non-glycosylated proteins with a molecular mass of less than 50 kDa. Since peptide/protein drugs are not absorbed orally, prolonged maintenance of therapeutically active drugs in the circulatory system is of primary clinical importance. Another major obstacle of injected polypeptide drugs is the elevated concentration of 100–1000 times above the therapeutical level that may be present in the circulatory system shortly after administration. Such overdosing may lead to undesirable side effects such as over-stimulation or down-regulation of receptor sites. In this review we describe two new strategies that overcome these two problems of systemically injected peptide/protein drugs. The first strategy includes Fmoc and FMS derivatization of peptides, proteins and low molecular-weight drugs, converting them to inactive prodrugs that undergo reactivation with desirable pharmacokinetic patterns in body fluids. Based on this Fmoc/FMS-technology, we have developed a second strategy, reversible pegylation. Inactive pegylated peptide/protein drugs release the native active parental molecule at slow rates, and in homogeneous fashion under physiological conditions, thus facilitating prolonged therapeutic effects, following a single administration.  相似文献   
87.
88.
骨关节炎(osteoarthritis,OA)是运动系统常见的退行性疾病,具有高发病率和高致残率。骨关节炎的发病机制目前尚不明确,既往研究认为骨关节炎发病主要与创伤因素相关,而近期研究表明,以胆固醇代谢异常为主的代谢性因素同样与骨关节炎密切相关,骨关节炎的治疗以早期对症治疗和晚期手术治疗为主,尚无针对病因的特效药物。既往研究中发现,有一种具有软骨保护作用的小分子药物BNTA,其在创伤引起的骨关节炎中具有较好的疗效,但其对高胆固醇引起的骨关节炎的作用尚不明确。本研究为探究BNTA对高胆固醇引起的骨关节炎的治疗作用及其机制,采用高胆固醇饮食构建了大鼠骨关节炎模型,取膝关节石蜡切片进行组织学评估,使用油红O染色评估大鼠软骨细胞内的脂质积聚情况,使用RT-qPCR、免疫荧光和免疫组化评估软骨细胞合成代谢、分解代谢及胆固醇代谢相关基因和蛋白质的表达。结果显示,BNTA可缓解高胆固醇大鼠骨关节炎模型中的病理表现,改善OARSI评分。在大鼠软骨细胞中,BNTA可促进合成代谢相关基因col2、sox9、acan的表达,抑制分解代谢相关基因mmp13、adamts5的表达,可改善高胆固醇引起的大鼠软骨细胞脂质积聚。在大鼠软骨细胞和高胆固醇大鼠骨关节炎模型中BNTA均可上调Insig1表达。本研究证实,高胆固醇可在体内和体外实验中加重骨关节炎,可引起大鼠软骨细胞脂质积聚增加。在体内和体外实验中BNTA均能缓解高胆固醇引起的骨关节炎表型,改善软骨细胞内的异常脂质积聚,其作用可能为通过上调Insig1抑制细胞内的胆固醇生物合成,从而缓解脂质异常积聚。  相似文献   
89.
Antiepileptic drugs (AED) have been associated to in vivo deleterious consequences in bone tissue. The present work aimed to characterize the cellular and molecular effects of five different AED on human osteoclastogenesis and osteblastogenesis. It was observed that the different drugs had the ability to differentially modulate both processes, in a way dependent on the identity and dose of the AED. Shortly, valproic acid stimulated either osteoclastogenesis and osteoblastogenesis, whereas carbamazepine, gabapentin, and lamotrigine revealed an opposite behavior; topiramate elicited a decrease of osteoclast development and an increase in osteoblast differentiation. This is the first report describing the direct effects of different AED on human primary bone cells, which is a very important issue, because these drugs are usually consumed in long-term therapeutics, with acknowledged in vivo effects in bone tissue.  相似文献   
90.
Cyclooxygenase-2 is a very important physiological enzyme playing key roles in various biological functions especially in the mechanism of pain and inflammation, among other roles, making it a molecule of high interest to the pharmaceutical community as a target. COX 2 enzyme is induced only during inflammatory processes or cancer and reflects no role in the guarding stomach lining. Thus, selective COX-2 inhibition can significantly reduce the adverse effects including GI tract damage and hepatotoxic effects of traditional NSAIDs like aspirin, ibuprofen, etc. Recent developments on COX-2 inhibitors is primarily focused on improving the selectivity index of the drug towards COX-2 along with enhancing the potency of the drug by modifying the scaffolds of Coxibs currently in the market like Celecoxib, Indomethacin, Oxaprozin, etc. We have reported the progress on new COX-2 inhibitors in the last decade (2008–2019) focussing on five heterocyclic rings- Pyrazole, Indole, Oxazole, Pyridine and Pyrrole. The addition of various moieties to these core rings and their structure-activity relationship along with their molecular modelling data have been explored in the article. This review aims to aid medicinal chemists in the design and discovery of better COX-2 inhibitors constructed on these five heterocyclic pharmacophores.  相似文献   
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