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81.
S Benk? S Drabant G Grézal I Urm?s M Cs?rg? I Klebovich 《Canadian Metallurgical Quarterly》1997,47(8):913-916
A comparative pharmacokinetic study has been performed in 19 healthy male volunteers in a single-dose, randomized, two way cross-over design with two preparations of gemfibrozil (CAS 25812-30-0) capsules each of them containing 300 mg active ingredient. The test preparation was Innogem 300 mg capsule. The plasma concentration of gemfibrozil was determined by a validated HPLC-UV analytical method. The statistical comparison of individual pharmacokinetic parameters (AUC0-16, AUC0-oc Cmax, tmax) of the two capsule preparations was performed by three-way analysis of variance (ANOVA), Wilcoxon's, Westlake's, Schuirmann's and Hanck-Anderson's method as well as by the calculation of confidence intervals on the ratio of test/reference. The relative bioavailability of the test preparation with respect to the reference preparation in terms of the AUC0-oc was 104.06 +/- 21.61%. No statistically significant difference was found between the pharmacokinetic parameters, calculated from plasma concentration-time curves, indicating that the two preparations were bioequivalent. 相似文献
82.
D Popovi? 《Canadian Metallurgical Quarterly》1997,50(11-12):559-563
Tissue and organ transplantation is a very complex interdisciplinary treatment, particularly in regard to unpaired organs, and it carries numerous risks for all participants in such an action. For the purpose of minimizing the risks to the allowed level and the preservation the humanitarian goals in medicine when performing the transplantation, professional and scientific doctrines and the respect of ethical and legal principles should be strictly observed. The paper presents the basic approaches in the estimation of justification, usefulness and certain forms of responsibility in the process of transplantation. Ethical and legal postulates which support transplantation to prevent deviation, deprivation or delinquency have also been reviewed. 相似文献
83.
84.
JM Derlon MC Petit-Taboué F Chapon V Beaudouin MH No?l C Creveuil P Courtheoux JP Houtteville 《Canadian Metallurgical Quarterly》1997,40(2):276-87; discussion 287-8
OBJECTIVE: The object of the present study was to identify metabolic differences between low-grade astrocytomas and oligodendrogliomas and to improve their diagnosis and noninvasive assessment, because both types of tumors look very similar from the point of view of clinical and radiological data (as assessed by computed tomography and magnetic resonance imaging). METHODS: Before any aggressive treatment, 22 patients with primary low-grade gliomas (astrocytomas in 12 patients and oligodendrogliomas in 10) were investigated with positron emission tomography for both glucose metabolism (18F-fluorodeoxyglucose) and amino acid uptake (11C-L-methylmethionine). An original software that allows a full metabolic analysis of the tumor region of interest (defined from the T1-weighted magnetic resonance image) and compares tumor tissue uptake tracer concentrations with average healthy tissue values has been implemented for data processing. Heterogeneity of each individual tumor has been taken into account and was expressed in histograms, which provided data about the mean and also extreme and intermediate values of tracer concentrations and the way these values are distributed among the full tumor mass. RESULTS: It has been shown that both tumor types exhibit a glucose hypometabolism (slightly more pronounced with astrocytomas), whereas they strongly differ in methionine uptake, which is high in all oligodendrogliomas and either decreased, normal, or moderately increased in astrocytomas. This latter metabolic difference between both tumor populations may be partially explained by their different cell densities. CONCLUSION: This study suggests that despite similar radiological and clinical presentations, these two kinds of low-grade gliomas are metabolically different and could therefore have specific responses to different therapies. Moreover, their in vivo metabolic follow-up with positron emission tomography should rely on different parameters, depending on their histological type; methionine uptake may be more relevant than glucose metabolism in the follow-up of oligodendrogliomas. 相似文献
85.
The cytosolic chaperonin containing TCP-1 (CCT) is known to keep fold cytoskeletal proteins and is involved in the proper organization of the cytoskeleton. These studies are based on the assumption that growth responses linked to structural rearrangement of the plant cytoskeleton include the action of CCT and the need for newly synthesized tubulin. The presence of the alpha- and epsilon-subunits of CCT was investigated in soluble fractions of protein extracts from maize mesocotyls and coleoptiles at distinct growth stages. The CCT-subunits, tubulins and actin decreased in the coleoptile in response to far-red light. In addition, independent from light treatment, the amount of CCT epsilon abundance declined with age in coleoptiles and mesocotyls between 2 and 4.5 days after sowing. In contrast to CCT epsilon, no significant light regulation of CCT alpha was found in the mesocotyl. In two day old, light-grown rapidly elongating coleoptiles part of the CCT alpha subunit and the bulk of actin and tubulin was found shifted into fractions of high molecular weight complexes when compared to slowly elongating, dark grown coleoptiles. In 4.5 day old, etiolated and elongating coleoptiles, part of both CCT-subunits and cytoskeleton proteins were found in fractions of high molecular weight. A complete disappearance of these polypeptides was observed in old far-red irradiated growth-arrested coleoptiles. CCT epsilon was found to be colocalized to microtubular structures and to the nucleus. We conclude from our data that abundance of CCT-subunits in soluble extracts is dependent on age and light treatment, but independent from the growth stage of mesocotyl and coleoptile. 相似文献
86.
J Weber P Majer J Litera J Urban M Soucek J Vondrásek J Konvalinka P Novek J Sedlácek P Strop HG Kr?usslich I Pichová 《Canadian Metallurgical Quarterly》1997,341(1):62-69
The results of investigation of haptoglobin (Hp) types in 596 donor blood samples in some towns of Ukraine (Dnepropetrovsk, Kharkov, Odessa, Kiev, Uzhgorod, Zhitomir) are presented. Three normal Hp types (Hp1-1, Hp2-1 and Hp2-2) have been found. The reliable interpopulation differences in the Hp types frequency were not found. On the whole the Hp types frequency in the type Hp1-1 comprised 12.7%. In the type Hp2-1-48.1% and in the type Hp2-2-36.5%. The frequency of the gene Hp1 is 0.38. The frequency of the Hp types and of the gene Hpl in Ukraine is similar to that in population of Eastern Europe and European Part of Russia. 相似文献
87.
Two Ghanaian women, aged 21 and 29 years, who were involved in road traffic accidents sustaining blunt trauma to the chest and who had delayed diagnosis of their total bronchial rupture and underwent successful surgical repair 18 and 29 months, respectively after injury are reported with a review of the literature. We believe these to be the first reported cases of delayed diagnosis and successful repair of total bronchial rupture in Tropical Africa. 相似文献
88.
89.
BACKGROUND: To maintain good exposure during major video-assisted thoracic surgery it is necessary to deflate completely the ipsilateral lung. However, little is known about the effects of one-lung ventilation (OLV) on pulmonary function in newborn patients. METHODS: Ten neonatal domestic pigs with a mean age of 6+/-0.6 days were intubated and ventilated in pressure-controlled mode (inspired oxygen fraction=1.0). One-lung ventilation was maintained for 120 minutes. Serial measurements of hemodynamics and gas exchange were done before, during, and until 90 minutes after OLV. Pulmonary function testing was performed before and after OLV for each lung separately. RESULTS: With the inspired oxygen fraction set at 1.0, arterial oxygen saturation remained stable at 100% during OLV. Venous admixture and alveolar-arterial oxygen tension gradient increased slightly from the baseline value of 2.6% +/-0.3% to 3.8%+/-0.3% during OLV (mean+/-standard error of the mean; p=0.02), and from 358+/-28 to 407+/-18 mm Hg (not significant), respectively. Both values returned to baseline during the subsequent ventilation of both lungs. Static compliance and resistance of the ventilated lung did not change. Compliance of the collapsed lung decreased after reexpansion from 0.42+/-0.07 to 0.29+/-0.06 mL x cm H2O(-1) x kg(-1), p=0.008). Resistance remained unchanged (0.22+/-0.02 versus 0.25+/-0.05 cm H2O x L(-1) x s(-1); not significant). CONCLUSIONS: There were only minor effects on pulmonary function during and after OLV in the neonatal piglet. Alterations in gas exchange during OLV were minimal. Prolonged collapse of the lung with subsequent reexpansion was associated with a slight decrease in compliance, indicating some mild lung injury. 相似文献
90.
J Pa?yga 《Canadian Metallurgical Quarterly》1998,36(3-4):79-92
Three polymorphic subtypes of erythrocyte histone H1 (H1.a, H1.b, and H1.z) were analyzed using a sodium dodecyl sulfate polyacrylamide gel in quail populations divergently selected for a high (line 1) or low (line 2) reduction in body mass following temporary food withdrawal. Both H1.b and H1.z histone alleles were found to be differently distributed in these populations during the selection period. The frequency of b1 in line 2 was approximately 1.9-2.8 times lower than in line 1 and approached the values in line 1 when the selection was suspended. Similarly, the frequency of allele z2 at locus H1.z increased significantly (about 1.6-2.3 times) in line 2 during selection and returned to the initial values when selection was stopped. On the other hand, allele a0 at locus H1.a was kept at relatively low levels (usually below 0.05) in both lines during selection. At that time its level was approximately three to four times lower than in a random mating control population. When selection was suspended, the frequency of a0 in line 1 increased significantly, approaching the values in the control line, and remained essentially unchanged in line 2. Thus, all three polymorphic histone H1 loci in quail responded through changes in allele frequencies to the breeding selection, which was directed at the amount of body weight loss upon transient starvation. It seems that either H1 histone locus could be linked to loci controlling the rate of body weight reduction following starvation or weight loss during fasting might be influenced by a panel of H1 histone alleles that can contribute to functional differences in avian chromatin. 相似文献