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211.
This study compared the effects of angiotensin converting enzyme (ACE) inhibitors captopril versus enalapril on left ventricular (LV) muscle mass and LV systolic and diastolic function in 58 patients with primary glomerulonephritis and moderate chronic renal failure. The design was a 6-8 week titration phase and 6-month maintenance phase. Mean myocardial mass calculated by M-mode echocardiography in the captopril group was 153 +/- 26 g/m2 before, and 130 +/- 14 g/m2 after 6 months of treatment, in enalapril group 147 +/- 22 g/m2 before, and 126 +/- 23 g/m2 after 6 months of treatment (p < 0.05). LV ejection fraction, early and late transmitral flow velocities and early to late LV inflow velocities ratio were not significantly affected by both ACE inhibitors. 相似文献
212.
The O antigen is a polymer with a repeated unit. The chain length in most Escherichia coli strains has a modal value of 10 to 18 O units, but other strains have higher or lower modal values. wzz (cld/rol) mutants have a random chain length distribution, showing that the modal distribution is determined by the Wzz protein. Cloned wzz genes from E. coli strains with short (7 to 16), intermediate (10 to 18), and long (16 to 25) modal chain lengths were transferred to a model system, and their effects on O111 antigen were studied. The O111 chain length closely resembled that of the parent strains. We present data based on the construction of chimeric wzz genes and site-directed mutagenesis of the wzz gene to show that the modal value of O-antigen chain length of E. coli O1, O2, O7, and O157 strains can be changed by specific amino acid substitutions in wzz. It is concluded that the O-antigen chain length heterogeneity in E. coli strains is the result of amino acid sequence variation of the Wzz protein. 相似文献
213.
AD Anichkov AV Vodianov SV Mozhaev TN Trofimova VB Nizkovolos AV Obliapin IuZ Polonski? AL Spirin 《Canadian Metallurgical Quarterly》1998,(3):6-9; discussion 9-10
The paper summarizes experience with stereotactic operations by magnetic resonance imaging data by using a Russian OREOL stereotactic manipulator. It describes methods of preoperative preparation of patients by employing diagnostic magnetic resonance tomographs. A number of points of the procedure for identification and localization of deep target structures from magnetic resonance images in parkinsonism, temporal epilepsy and some mental disorders. 相似文献
214.
MI Youshko TA Shamolina DF Guranda AV Synev VK Svedas 《Canadian Metallurgical Quarterly》1998,63(9):1104-1109
Penicillin acylase substrates suitable for colorimetric determination of the enzyme activity have been tested in this study. The kinetic parameters (Km and kcat) have been elucidated for the following nine substrates: six phenylacetic acid derivatives (p-nitroanilide, p-nitrophenyl ester, p-nitro-m-carboxyanilide, p-nitro-o-carboxyanilide, p-nitro-o-hydroxyanilide, m-nitro-p-carboxyanilide), two D-phenylglycine derivatives (p-nitroanilide, p-nitro-m-carboxyanilide), and also p-nitrophenyl ester of acetic acid (p-nitrophenyl acetate). With the exception of p-nitrophenyl acetate, all the compounds studied are highly specific chromogenic substrates for penicillin acylase, but their reactivity is very variable and kcat/Km values are in a range from 0.8.10(4) to 5.10(6) M(-1).sec(-1). 相似文献
215.
H Dosogne AV Capuco MJ Paape E Roets C Burvenich B Fenwick 《Canadian Metallurgical Quarterly》1998,81(3):672-677
Bovine neutrophils contain the enzyme acyloxyacyl hydrolase, which hydrolyzes the acyloxyacyl linkage of the two nonhydroxylated fatty acyl chains to two 3-hydroxy fatty acids in the highly conserved lipid A part of endotoxins with high specificity. This hydrolysis decreases the toxicity of lipid A, but the immunostimulatory capacity of endotoxins is largely maintained. In two trials, we studied the activity of acyloxyacyl hydrolase in neutrophils that had been isolated from the blood of 18 dairy cows around parturition. Between 10 and 26 d after parturition, the activity of acyloxyacyl hydrolase in neutrophils decreased approximately 20% below prepartum activity. At about 2 mo after parturition, acyloxyacyl hydrolase activity returned to prepartum values. Changes in acyloxyacyl hydrolase activity could not be attributed to changes in binding of lipopolysaccharides by the CD14 molecules on neutrophils or monocytes. We hypothesize that decreased acyloxyacyl hydrolase activity in neutrophils shortly after parturition is a factor that increases the susceptibility of dairy cows to coliform mastitis during early lactation. 相似文献
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AV Gasparian KK Laktionov MS Belialova NA Pirogova AG Tatosyan IB Zborovskaya 《Canadian Metallurgical Quarterly》1998,77(10):1604-1611
The mapping of allelic loss on the short arm of chromosome 1 has been performed in non-small-cell lung cancer. We used a set of 11 microsatellite loci spanning 1p to examine the frequency of allelic imbalance in a panel of 58 tumours. Fifty-one of 58 (87.9%) cases have shown somatic allelic loss at one or more loci tested. The two shortest regions of the overlap (SRO) of the deletions have been identified: SRO 1 at 1p13.1 and SRO 2 at 1p32-pter. Allelic losses at these regions have been compared among adenocarcinoma and squamous cell carcinoma and no difference has been found. In contrast to SRO 1, deletions at SRO 2 significantly correlated with advanced stage of the disease as well as post-operative metastasizing and relapse. These data may suggest that SRO 1 and SRO 2 can harbour tumour-supressor genes (TSGs) involved in different stages of NSCLC development. SRO 2 is still quite large and its refined mapping should help attempts to clone and identify the putative TSG(s). Microsatellite instability (replication errors) affecting only 6 (10.3%) of 58 tumour samples is an infrequent genetic alteration at the loci tested. 相似文献
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220.
AV Sidorov VV Zverev AG Zdanovski? AV Pugach VV Maliushova OG Andzhaparidze 《Canadian Metallurgical Quarterly》1994,39(1):6-10
Lack of uniformity in the classification of oral diseases, and variability of study designs, measurements, methods, and statistical formats, hamper the interpretation, comparison and review of the evidence linking smoking and oral diseases. However, there have been a significant number of controlled studies, allowing definitive conclusions to be drawn. This review of 22 controlled scientific studies from 1983-1992, considers the role of smoking as an aetiological agent in: gingival problems (impaired gingival bleeding, ANUG), periodontal problems (periodontitis, bone loss, tooth loss), and caries. 相似文献