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31.
Roxatidine acetate, a new H2 receptor antagonist, was compared with ranitidine in the treatment of duodenal ulcers in a double-blind multicentre study. Eighty-four patients with endoscopically proven duodenal ulcer were randomized to receive 150 mg roxatidine acetate or 300 mg ranitidine at bedtime. Repeat endoscopy was performed after 4 weeks (25–33 days) and if the ulcer had not healed, another endoscopy was performed after a further 4 weeks of treatment. Using per protocol analysis 73.6% of ulcers treated with roxatidine healed at 4 weeks compared to 72.2% of ulcers treated with ranitidine (P=NS). The healing rates at 8 weeks were 92% with roxatidine and 83.3% with ranitidine (P=NS). Using equivalence tests, the healing rate of roxatidine was found to be equivalent to that of ranitidine within a 20% region. Roxatidine users took significantly less antacids than ranitidine users (P < 0.05). There were no significant adverse effects due to roxatidine or ranitidine. Roxatidine is a safe effective drug in the treatment of duodenal ulcers with a healing rate comparable to that of ranitidine.  相似文献   
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AIM: To evaluate whether cortical scars can be detected using the summed images of technetium-99m-L,L-ethylenedicysteine (99mTc-L,L-EC) renal dynamic scan, and to compare the results with technetium-99m-dimercaptosuccinic acid (99mTc-DMSA) scan. To evaluate the inter-observer variability for 99mTc-L,L-EC and 99mTc-DMSA scan reporting. METHODS: One hundred and three patients were initially included in the study; 21 were excluded, five due to a single functioning kidney and 16 due to impaired renal function (serum creatinine>2.5 mg.dl(-1)). Eighty-two patients (39 females, 43 males), including 31 children, with a mean age of 33.4+/-11.3 years (range, 4 months to 74 years), underwent both 99mTc-DMSA and 99mTc-L,L-EC scintigraphy within a period of 14 days. 99mTc-L,L-EC images were regrouped into 2 min image sets, and the initial 2 min summed image (cortical phase) was used for the evaluation of scars. Three independent observers analysed both images separately on different days without being aware of the identity and clinical details of the patients. Their 99mTc-L,L-EC findings were compared with the consensus 99mTc-DMSA scan findings taken as reference. RESULTS: The overall sensitivity of 99mTc-L,L-EC scans was 93% and the specificity was 96%. The inter-observer variability was 0.91 for 99mTc-L,L-EC and 0.94 for 99mTc-DMSA scan reporting, using the weighted kappa analysis at P<0.05. CONCLUSIONS: 99mTc-L,L-EC is an excellent single-modality comprehensive investigational agent for renal morphology, function and outflow tract evaluation with the added advantages of lower cost, convenience and low radiation exposure to the patient.  相似文献   
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Wedelolactone (WL) and demethylwedelolactone (DWL) isolated from Eclipta alba were tested in the trypsin inhibition bioassay (in vitro). Both compounds showed potent activity. IC(50) values of WL and DWL were found to be 2.9 and 3.0 microg/mL respectively.  相似文献   
35.
A community based study was Conducted in the rural areas of Udupi taluk, Karnataka state of South India to identify the socio-demographic, maternal and obstetric determinants of low birth weight. All singleton live births that occurred in the study area during a one year period (October 1991 to September 1992) were included. A total of 2919 singleton child-mother pairs formed the basis of the analysis. Information about social, demographic and economic conditions of the families; maternal factors such as age, parity, quality of antenatal care and previous obstetric history were collected by interviewing the mothers and family members and verifying the available medical records through the field investigators especially recruited and trained for this purpose. Data was analyzed using multiple logistic regression model. Primis, elderly mothers and mothers who had not received good quality antenatal care were found to be more at risk of having low birth weight babies. Other significant determinants were family custom, socio-economic status and environmental sanitation.  相似文献   
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亮氨酸脑啡肽的电子结构及构效关系研究   总被引:1,自引:0,他引:1  
对亮氨酸脑啡肽进行了量子化学(INDO)计算,研究其电子结构特征,讨论其活性部位、作用机理及构效关系。同吗啡和R31833进行了活性部位的电子结构与空间结构比较,推断它们的活性药效结构具有共同特点,与阿片受体相互作用时作用方式相同,作用部位有对应关系,因而具有相同的药理性质。  相似文献   
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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   
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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   
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