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81.
82.
Nucleotide sequences from two nuclear loci, alcohol dehydrogenase and internal transcribed spacer-1 of the nuclear ribosomal DNA repeats, and two mitochondrial genes, cytochrome oxidase I and cytochrome oxidase II, were determined from nine species in the Drosophila saltans species group. The partition homogeneity test and partitioned Bremer support were used to measure incongruence between phylogenetic hypotheses generated from individual partitions. Individual loci were generally congruent with each other and consistent with the previously proposed morphological hypothesis, although they differed in level of resolution. Since extreme conflict between partitions did not exist, the data were combined and analyzed simultaneously. The total evidence method gave a more resolved and highly supported phylogeny, as indicated by bootstrap proportions and decay indices, than did any of the individual analyses. The cordata and elliptica subgroups, considered to have diverged early in the history of the D. saltans group, were sister taxa to the remainder of the saltans group. The sturtevanti subgroup, represented by D. milleri and D. sturtevanti, occupies an intermediate position in this phylogeny. The saltans and parasaltans subgroups are sister clades and occupy the most recently derived portion of the phylogeny. As with previous morphological studies, phylogenetic relationships within the saltans subgroup were not satisfactorily resolved by the molecular data. 相似文献
83.
MG Tibiletti M Trubia E Ponti L Sessa F Acquati D Furlan B Bernasconi M Fichera A Mihalich A Ziegler A Volz C Facco C Riva L Cremonesi M Ferrari R Taramelli 《Canadian Metallurgical Quarterly》1998,16(12):1639-1642
A detailed long range restriction map of the region defined by markers D6S149 and D6S193 on chromosome 6q27 has been constructed. This was achieved by YAC cloning and contig assembling of the same region. Seven YAC clones were found to span the almost 1000 Kb region flanked by the two markers which on the genetic map resulted to be 1.9 cM apart. With some of the characterized YAC clones we undertook a molecular cytogenetic analysis of 20 benign ovarian tumors. The rationale for this was the recent mapping to a region of chromosome 6q27, flanked by markers D6281 and D6S133, of a locus for the SV40-mediated immortalization of human cells (SEN6 gene). Noteworthy we found that the the D6S149-D6S193 region (comprised in the larger D6S281-D6S133 physical interval) was altered in all samples analysed adding support to the occurrence of a immortalization step in this type of tumors. 相似文献
84.
Y Bergeron N Ouellet AM Deslauriers M Simard M Olivier MG Bergeron 《Canadian Metallurgical Quarterly》1998,42(10):2527-2533
It has recently become apparent that overwhelming inflammatory reactions contribute to the high mortality rate associated with pneumococcal infection in immunocompetent hosts. Cefodizime (CEF) is an antibiotic that seems to be endowed with immunomodulating properties. To investigate the influence of CEF on the pulmonary inflammatory response induced by Streptococcus pneumoniae, we infected mice with repeated intranasal inoculations of 10(7) CFU of heat-killed fluorescein isothiocyanate-labeled bacteria, which are insensitive to the killing properties of the drug. CEF downregulated but did not abolish the strong polymorphonuclear leukocyte (PMN) recruitment induced by S. pneumoniae. PMN recruitment was not primarily mediated by leukotriene B4 in this model. The drug did not interfere with intrinsic mechanisms of phagocytosis by PMNs and alveolar macrophages. CEF totally abrogated the pneumococcus-induced tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6) secretion in bronchoalveolar lavage fluid. The drug also prevented IL-6 release in lung homogenates and partly inhibited TNF-alpha, but it did not interfere with IL-1alpha secretion in the lungs of infected mice. The fractional and selective downregulation of inflammatory cells and cytokines by CEF suggests cell-specific and intracellular specific mechanisms of interaction of the drug. The immunomodulatory properties of CEF may help restrain excessive inflammatory reactions, thus contributing to the reported good clinical efficacy of the drug against lower respiratory tract infections. 相似文献
85.
AV Susekov MG Tvorogova GG Arabidze VV Kukharchuk 《Canadian Metallurgical Quarterly》1998,70(9):57-61
AIM: The study of the hypolipidemic efficiency, safety and tolerance of ciprofibrate (lipanor) in therapy of atherogenic hyperlipoproteinemia. MATERIALS AND METHODS: The trial included 14 hypertensive postmenopausal females, 14 patients with diabetes mellitus type II, 14 males with coronary heart disease and primary hyperlipoproteinemia (total cholesterol > 6.5 mmol/l, triglycerides < 4.5 mmol/l under low-cholesterol diet). Lipanor was given for 12 weeks in a daily single dose 100 mg in the morning. Lipids and other biochemical indices were measured in a fasting state after 1 and 3 months of lipanor treatment. RESULTS: After 1 month of lipanor treatment there was a 22-30%, 24-49% decrease in the level of low-density lipoprotein cholesterol, triglycerides, respectively. High-density lipoprotein cholesterol increased by 16%. The hypolipidemic effect of lipanor persisted for 3 months during which triglycerides continued to fall (up to 38.5%). Lipanor was well tolerated, only one patient with diabetes mellitus had hyperactivity of creatine phosphokinase manifesting with clinical symptoms (the drug was discontinued). 3 patients developed mild side effects. Alkaline phosphatase activity inhibited in all the groups by 25-41%. CONCLUSION: Lipanor is a highly effective, safe hypolipidemic drug with good tolerance. It can be recommended for correction of atherogenic hyperlipoproteinemia in patients at high risk of atherosclerosis progression. 相似文献
86.
BACKGROUND: Although a compulsory examination in medical English has been present in the medical degree curriculum in Italy since 1990, guidelines indicating what should be learnt and suggesting some means of overcoming the various problems this entails are still lacking. OBJECTIVE: To investigate the main features of teaching English in the Medical Faculties and enquire into how the various problems are solved in the individual English teaching units. METHOD: A questionnaire addressing the above issues was sent out to all the Italian Universities with a Medical Faculty. RESULTS: The first finding of our survey was that response was very poor: less than 30% of the survey volunteered any reply. Within the very reduced sample which responded, there was a high degree of variation among the solutions adopted, although the underlying problems were perceived to be much the same throughout Italy. CONCLUSIONS: The general objective of the English course for medicine should be more precisely defined, together with a series of specific minimum skills the student should possess to pass the final examination. A closer collaboration among the English teaching units might help to standardize these requirements, improve the quality of the teaching and hence the level of proficiency in English for the specific purpose of medical practice. 相似文献
87.
An integrated design procedure which is composed of structural design, control design, and actuator locations design is proposed in this paper. First, a composite objective function, formed by a structural and a control objective, is optimized in steady state through the homogenization design method. Then an independent modal space control algorithm (IMSC) is performed on this optimal structure to reduce the dynamic response. Finally, to minimize the control force while still obtaining the same modal response for the controlled modes, the optimal choice for actuator locations is discussed.Part of this paper was presented in the First World Congress of Structural and Multidisciplinary Optimization (held in Goslar, Germany, May 28–June 2, 1995). 相似文献
88.
A formulation that finds the optimal design of a controlled structure is proposed. To achieve this goal, a composite objective composed of structural and control objectives is introduced to be optimized, and the effect of the control weighting is examined. A feedback control law is defined before the structural optimization and then the composite objective will only become a function of structural design variables. As a result, optimal structural design and control forces in steady state are obtained.Part of this paper was presented at WCSMO1 (First World Congress of Structural and Multidisciplinary Optimization), held in Goslar, Germany, May 28–June 2, 1995 相似文献
89.
90.