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41.
Asongalem EA Foyet HS Ngogang J Folefoc GN Dimo T Kamtchouing P 《Journal of ethnopharmacology》2004,91(2-3):301-308
This study was intended to evaluate the analgesic and antiinflammatory activities of an aqueous extract of Erigeron floribundus (H.B. & K) or (syn": Conyza sumatrensis (Retz) E.K. Walker) (Asteraceae). Phytochemical analysis was carried out using standard methodologies. The analgesic investigations were carried out against two types of noxious stimuli, chemical (formalin-induced pain and acetic acid-induced writhing) and thermal (hotplate and tail immersion tests). The effects following aspirin and naloxone pretreatments were also studied. For the antiinflammatory activities, the carrageenan-induced oedema of the hindpaw of rats was used and the paw volume measured plethysmometrically from 0 to 24 h after injection. This was compared to a standard drug indomethacin (10 mg/kg). The results were subjected to statistical analysis. The plant had saponins, flavonoids, glycosides, alkaloids, oils, phenols and tannins and significantly increased the reaction time of hotplate and immersion tests. It decreased the writhings of acetic acid-induced abdominal contractions and lickings of formalin-induced pain. Aspirin had no effect on hotplate and tail immersion tests but showed an effect on writhing test. These results showed that the plant had both central and peripheral acting effects and this was confirmed by its effect on both phases of formalin-induced pain. The extract also significantly decreased the rat paw oedema volume at 50 mg/kg and above. In conclusion, Erigeron floribundus has central and peripheral analgesic properties as well as antiinflammatory activities. 相似文献
42.
7β-(6-取代-2-喹诺酮-3-乙酰氨基)头孢菌素的合成 总被引:1,自引:0,他引:1
以6-取代-2-喹诺酮-3-乙酸为侧链,用CDI法和潘化酯法与7-ADCA,7-ACA,7-ACT,和7-ACD缩合,合成了16个新的7β-(6-取代-2-喹诺酮-3-乙酰氨基)头孢菌素类化合物,通过溶媒转提,葡聚糖凝胶(Sephadex LH-20)柱层析及离心薄层层析分离精制,得到纯品。初步体外抑菌试验表明:新化合物对革兰氏阳性及某些阴性菌具有高度敏感性。大多数化合物对所试试验菌的抗菌活性与头孢唑啉和青霉素G钠相当,有些比它们还强。 相似文献
43.
Cloning and expression of the gene involved in Sanfilippo B syndrome (mucopolysaccharidosis III B) 总被引:4,自引:1,他引:4
Sanfilippo B syndrome is caused by a deficiency of alpha-N-
acetylglucosaminidase, a lysosomal enzyme involved in the degradation of
heparan sulphate. Accumulation of the substrate in lysosomes results in
degeneration of the central nervous system with progressive dementia often
combined with hyperactivity and aggressive behaviour. In order to clone the
deficient gene, we purified the enzyme from human placenta and obtained
amino acid sequence information. Alignment of one of the CNBr generated
internal peptides to sequence from the database revealed the chromosomal
location of the gene in the 5' upstream flanking region of the gene for
17-beta-hydroxysteroid-dehydrogenase at 17q21.1. The available DNA sequence
was used to clone the cDNA coding for alpha-N- acetylglucosaminidase and
analyse its gene structure. The gene is fully contained in the 5' upstream
flanking region of the gene for 17-beta- hydroxysteroid-dehydrogenase and
interrupted by five introns. The cDNA clone has a length of 2575 bp and
encodes a protein of 743 amino acids. Chinese hamster ovary cells
transfected with the cDNA construct show alpha-N-acetylglucosaminidase
activity about 17-fold over background. This will allow correction studies
with NAG deficient Sanfilippo B cell lines and facilitate the development
of enzyme replacement therapy for these patients.
相似文献
44.
45.
Ming Zhao Yan‐Fang Xian Siu‐Po Ip Harry HS Fong Chun‐Tao Che 《Phytotherapy research : PTR》2010,24(9):1414-1416
A new protoberberine alkaloid, 3‐hydroxy‐2‐methoxy‐9,10‐methylenedioxy‐8‐oxo‐protoberberine, along with three known compounds, was isolated from Rhizoma Coptidis. The new compound displayed weak antispasmodic activity against acetylcholine‐induced contraction in isolated guinea‐pig ileum with an IC50 of 83.7 μm . Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
46.
颈动脉血管重构特征在自发性高血压大鼠体内的表现 总被引:2,自引:0,他引:2
目的:血管重构是高血压的重要病理变化,是高血压导致器官损害的结构基础。实验观察自发性高血压大鼠颈动脉中层组织学的相关变化,以验证血管重构的特点。方法:实验于2006-06/2007-03在福建医科大学附属协和医院心血管内科实验室完成。①实验材料及分组:12周龄雄性自发性高血压大鼠10只,同性别周龄的WKY大鼠10只为对照,喂养18周后终止实验。②实验过程及评估:开始及每2周测鼠尾收缩压。实验结束后,麻醉后取颈动脉,行苏木精-伊红、苦味酸-天狼星红、弹力纤维和胶原纤维的双重染色(P/VB法),利用计算机辅助成像系统测算颈动脉中膜厚度、腔径、血管中膜厚/腔径、中膜横截面积、中膜细胞平均核面积及中膜的胶原面积百分比、弹性纤维面积百分比、弹性纤维面积与胶原面积的比值。SP免疫组织化学染色检测α-平滑肌肌动蛋白、增殖细胞核抗原、纤维粘连蛋白、层粘连蛋白等抗原在颈动脉壁的表达,并计算颈动脉中膜细胞增殖指数;以原位末端标记法标记血管壁的凋亡细胞,计算颈动脉中膜细胞凋亡指数。结果:20只大鼠全部进入结果分析。①自发性高血压大鼠实验开始和结束前的收缩压均>150mmHg,高于WKY大鼠(P<0.01)。②自发性高血压大鼠颈动脉中膜厚度、腔径、中膜厚度/腔径、中膜横截面积、中膜胶原面积百分比均高于WKY大鼠(P<0.01),而中膜弹性纤维面积百分比、弹性纤维面积与胶原面积比值均低于WKY大鼠(P<0.01)。③α-平滑肌肌动蛋白在两组大鼠颈动脉中膜均可表达,提示中膜细胞为血管平滑肌细胞。④自发性高血压大鼠中膜血管平滑肌细胞平均核面积大于WKY大鼠(P<0.01),中膜细胞增殖指数与WKY大鼠差异无显著性(P>0.05),中膜细胞凋亡指数显著低于WKY大鼠(P<0.01)。⑤自发性高血压大鼠颈动脉中膜纤维粘连蛋白、层粘连蛋白的光密度值(IA值)及染色阳性面积百分比高于WKY大鼠(P<0.01)。⑥颈动脉中膜血管平滑肌细胞凋亡指数与中膜横截面积呈显著负相关(r=-0.872,P<0.01);纤维连接蛋白表达的吸光度值与中膜横截面积呈显著正相关(r=0.954,P<0.01)。结论:自发性高血压大鼠颈动脉存在明显的重构,其特点为中膜肥厚、平滑肌细胞肥大、凋亡减少及胶原、纤维粘连蛋白、层粘连蛋白的过度沉积。 相似文献
47.
Background: Calcium channel blockers potentiate the effects of local anaesthetics. We examined the effect of adding verapamil to local anaesthetic solution on anaesthetic duration in patients undergoing surgery under brachial plexus block. 相似文献
48.
49.
S. W. Woo PhD S. Bang HS M. W. Chung PhD S. K. Jin PhD Y. S. Kim† MD PhD S. H. Lee‡ MD PhD 《Journal of clinical pharmacy and therapeutics》2009,34(5):561-567
Background & Objective: Angiotensin converting enzyme (ACE) inhibitors are used widely in therapy for hypertension, congestive heart failure and myocardial infarction. However, coughing, one of their major adverse effects limits their use. It is documented that Asians are more liable to coughing than Europeans. The aim of this study was to investigate genetic polymorphism involved in ACE inhibitor-induced coughing.
Methods: We monitored hypertensive subjects ( n = 110) treated with ACE inhibitors, and tested for any associations between ACE inhibitor-induced coughing and polymorphisms in the genes for ACE and the bradykinin B2 receptor, which are suspected to be related to coughing.
Results & Discussion: We found no significant differences between the groups with coughing and without coughing in the frequency of ACE I/D (Insertion/Deletion) polymorphisms. One single nucleotide polymorphism was discovered in the promoter (−58T/C) and, one in intron-exon junction upsteam of exon 2 (−59C/A), of the bradykinin B2 receptor gene. However, no significant correlation was found between those genotypes or allele distributions and ACE inhibitor-induced coughing.
Conclusion: We found no significant links between polymorphisms of the ACE gene or bradykinin B2 receptor gene with ACE inhibitor-induced coughing in hypertensive Koreans. But, the topic remains controversial and requires more study. 相似文献
Methods: We monitored hypertensive subjects ( n = 110) treated with ACE inhibitors, and tested for any associations between ACE inhibitor-induced coughing and polymorphisms in the genes for ACE and the bradykinin B2 receptor, which are suspected to be related to coughing.
Results & Discussion: We found no significant differences between the groups with coughing and without coughing in the frequency of ACE I/D (Insertion/Deletion) polymorphisms. One single nucleotide polymorphism was discovered in the promoter (−58T/C) and, one in intron-exon junction upsteam of exon 2 (−59C/A), of the bradykinin B2 receptor gene. However, no significant correlation was found between those genotypes or allele distributions and ACE inhibitor-induced coughing.
Conclusion: We found no significant links between polymorphisms of the ACE gene or bradykinin B2 receptor gene with ACE inhibitor-induced coughing in hypertensive Koreans. But, the topic remains controversial and requires more study. 相似文献
50.