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Univariate and multivariate statistical analyses have been performed on 19 morphometric variables of adult male specimens belonging to three genetically identified species within Pseudoterranova decipiens (Nematoda: Ascaridida) parasitic in the digestive tract of seals. Two morphometric keys are proposed for the identification of the three species. One key, which uses two variables, determines a frequency of error of 3.8% (3/79). The second key, which uses two canonical discriminant functions based on seven variables previously selected with a stepwise procedure, gives 100% (76/76) accurate classification. 相似文献
74.
P. Cugini G. Leone P. Lucia F. A. Sepe A. Pelosio T. Caparrelli R. Verardi A. Zannella P. Zannella G. Pannozzo F. Di Fonzo F. P. Zannella 《Chronobiology international》1994,11(6):381-392
Noninvasive ambulatory blood pressure (BP) monitoring is a developing method in clinical practice. Its interpretation needs reference standards stratified by age and gender. This study addresses ambulatory BP monitoring in elderly people with the purpose of quantifying the discrete and periodic variability of BP pattern over a 24-h period. The ABPM was performed in 92 clinically healthy subjects (45 men and 47 women) ranging in age from 76 to 102 years. The results refer to the time-qualified mean values with their dispersion, to the circadian rhythm with its parameters, and to the daily baric impact (BI) with its variability. The conclusion is drawn that BP preserves its nychtohemeral variability and circadian rhythmicity despite old age. The daily BP mean level and BI in older people in good health are comparable with those of young subjects, suggesting that humans surviving into old age are characterized by a eugenic control of their pressure regimen. 相似文献
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P. Cugini C. Letizia S. Cerci L. Di Palma P. Battisti A. Coppola D. Scavo 《Chronobiology international》1993,10(2):119-122
This study deals with a chronobiological approach to the circadian rhythm of the renin-angiotensin-aldosterone system (RAAS) and the ACTH-cor-tisol axis (ACA) in patients with Addison's disease (PAD). The aim is to explore the mechanism(s) for which the circadian rhythmicity of the RAAS and ACA takes place. The study has shown that both the RAAS and ACA are devoid of a circadian rhythm in PAD. The lack of rhythmicity for renin and ACTH provides indirect evidence that their rhythmic secretion is in some way related to the circadian oscillation of aldosterone and cortisol. This implies a new concept: a positive feedback may be included among the mechanisms which chronoregulate the RAAS and ACA. 相似文献
78.
Pietro Cugini Loredana Di Palma Salvatore Di Simone Piernatale Lucia Paola Battisti Alessandro Coppola Giuseppe Leone 《Chronobiology international》1993,10(1):73-78
This study aimed to explore the 24-h patterns of stroke volume, cardiac output, and peripheral vascular resistance along with other correlated variables, such as left ventricular ejection time, ejection velocity index, thoracic fluid index, heart rate, and blood pressure. The study was performed on 12 clinically healthy subjects by means of a noninvasive beat-to-beat monitoring using the thoracic electric bioimpedance technique associated with the automated sphygmomano-metric recording. Time data series were analyzed by means of chronobiological procedures. The results documented the occurrence of a circadian rhythm for all the variables investigated, giving relevance to the beat-to-beat bioperiodicity of cardiac output and peripheral vascular resistance. Temporal quantification of the investigated variables may be useful for a better insight of the chronophysiology of the cardiovascular apparatus. 相似文献
79.
Xiong Zhang Ming-You Peng En-Ming Feng Qing-Dan Li Lu Chen Hu-Cheng Yang Bing Guo Hong Liang Ying-Tong Di Lei Tang Ying Yan 《化学与生物多样性》2023,20(10):e202301061
Three previously undescribed diterpenoids, helioscopnoids A–C, and eight known compounds were isolated from the whole plants of Euphorbia helioscopia. Their structures were established by extensive analysis of spectra and data comparison with previous literatures. Among them, compound 4 was identified as 24,24-dimethoxy-25,26,27-trinoreuphan-3β-ol with revised configurations of C-13, C-14, and C-17 (13R*, 14R*, 17R*). Cytotoxicity assays revealed that all compounds exhibited varying levels of cytotoxicity against H1975 cells, with compound 9 displaying the most potent activity, as indicated by cell viability rates of 18.13 % and 20.76 % at concentrations of 20 μM and 5 μM, respectively. This study expands the understanding of E. helioscopia terpenoids’ structural diversity and biological activities, contributing to the exploration of potential therapeutic applications. 相似文献
80.
A survey of literature for the various types of helices experimentally observed in high-resolution single crystal x-ray diffraction analyses of peptides has allowed to determine accurate conformational and helical parameters for the various secondary structures such as the alpha-helix, the 3(10)-helix, the fully extended conformation (2(5)-helix) and the beta-bend ribbon spiral. For each of these structures the characteristic phi, psi conformational parameters, n, the number of residues per turn, h, the height per residues and p, the pitch of the helix are described. 相似文献