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21.
A. Dal Monte F. Sardella B. Alippi M. Faina A. Manetta 《European journal of applied physiology》1994,69(2):159-162
We describe a new respiratory valve system with minimal dead space, which allows measurement of ventilation and oxygen uptake during swimming. The device offers considerable advantages in efficiency and accuracy over current equipment, and can be used in conjunction either with a miniaturized telemetry system for oxygen uptake measurement or with a conventional system. The valve has a low airflow resistance, a small dead space (15 ml), and an electrically operating, closed-circuit pump to remove excess water from the expiratory tube. The external form and the buoyancy of the valve have been hydrostatically and hydrodynamically designed to reduce drag and to ensure a correct mass in the water. To obtain this result a very sophisticated material, carbon fibre, has been utilized. Our studies showed that this respiratory system is ideal for obtaining valid and reliable values of oxygen uptake during swimming, even at high speed and in endurance swimming tests. 相似文献
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24.
A Dal Pozzo M Acquasaliente G Donzelli P DeMaria M C Nicoli 《Journal of medicinal chemistry》1987,30(9):1674-1677
A number of 3-carbonylacrylic acid derivatives were prepared, with a view to varying systematically the stereoelectronic environment of the conjugated double bond. The rates of reaction with cysteine were measured spectrophotometrically when possible or by stopped flow when very fast. Some of the final reaction products were isolated. Other properties examined were partition substituent constants and antimicrobial activity. On the basis of published data and these studies, the activity appears to be the combined effect of at least two mechanisms, one probably related to the effect of these structures on surface tension, the other to the electrophilic properties of the unsaturated system. 相似文献
25.
S. Bernander J. Dalén B. Gästrin L. Hedenborg L. O. Lamke R. Öhrn 《European journal of clinical microbiology & infectious diseases》1993,12(4):282-285
To test the validity of reports on detection ofHelicobacter pylori in the mouth, samples were obtained simultaneously from the gastric mucosa and dental plaques for culture in 94 patients examined consecutively by endoscopy. Histological examinations and serological tests were also performed.Helicobacter pylori was not found in the mouth of any of the patients including 52 who had culture-positive gastric biopsies. Thus earlier results could not be confirmed, however, other techniques such as the polymerase chain reaction might give different results. 相似文献
26.
Laura Santambrogio Maria Lipartiti Alessandro Bruni Roberto Dal Toso 《Journal of neuroimmunology》1993,45(1-2)
The presence of functional dopamine receptors on differentiated cells of the mammalian immune system is still under discussion. This study has utilized (-)-[3H]sulpride as a ligand to detect the presence of recognition sites of the dopamine D2 receptor family on human T- and B-lymphocytes. The (-)-[3H]sulpiride binding was of high affinity (Kd 0.9 nM ± 0.2 nM, specific, saturable (Bmax 10.2 ± 1.4 fmol/106 cells) and reversible. The pharmacological characterization of the recognition site suggests, similarities mainly with the D2 and D4 rather than D3 subtype of dopamine receptor. Furthermore, dopamine treatment was able to reduce the intracellular cAMP levels of lymphocytes stimulated with forskolin, thus suggesting a potential functional significance of this dopamine receptor in mediating neural-immune interactions. 相似文献
27.
A M Zotti G Ambroso G B Ambrosio G Vidotto C Dal Palù 《Giornale italiano di cardiologia》1989,19(2):136-144
The aim of this study was to evaluate the presence of "type A" behaviour and possible psychological distress in 373 hypertensive patients. One-hundred and ninety-five males, 56.2 +/- 6.2 years old and one-hundred and seventy-eight females, 57.1 +/- 6.2 years old, coming from the IPPPSH and still under double-blind treatment with or without a beta-blocker (oxprenolol 160 mg SR), were studied by means of the Jenkins Activity Survey form C and several tests from the Cognitive Behavioural Assessment Battery (CBA-2.0). Seventy-four point eight percent of the patients showed a "type A" pattern, and 25.5% were in the extreme predictive interval for coronary heart disease according to WCGS. "Type A" pattern was not influenced by variables such as age, sex, education, job or previous pharmacological treatment. The patients studied did not show any particular psychological distress at the psychometric evaluation. However, special social and cultural characteristics and different therapies influenced some symptoms, such as anxiety, depression and somatic lamentation. According to this study: "type A" behaviour seems to be a steady feature of the hypertensive patient; furthermore, it seems to be due to a "biological imprinting" which can be considered a cause of hypertension; psychological distress depends on a particular set of environmental stimuli. In the first case an accurate prevention is needed while, in the second case adequate pharmacological and/or psychological therapies are needed. 相似文献
28.
Genotypes and haplotypes in the IL-1 gene cluster: analysis of two genetically and diagnostically distinct groups of Alzheimer patients 总被引:5,自引:0,他引:5
Seripa D Matera MG Dal Forno G Gravina C Masullo C Daniele A Binetti G Bonvicini C Squitti R Palermo MT Davis DG Antuono P Wekstein DR Dobrina A Gennarelli M Fazio VM 《Neurobiology of aging》2005,26(4):455-464
Increased risk of Alzheimer's disease (AD) has been associated with polymorphisms in the IL-1 gene cluster, and in particular with the IL-1alpha-889 T/T genotype. However, this association is still unclear, and needs further investigation. In order to clarify the role of these polymorphisms in the complex pathogenesis of AD we examined genotype and haplotype frequencies of the two C-to-T SNPs at position -889 and -551 in the IL-1alpha and IL-1beta genes, respectively, and of the 86 bp VNTR intron-2 polymorphisms in the IL-1Ra gene. The analysis was performed in two genetically and diagnostically distinct groups of sporadic AD from Italy and the USA. In the Italian group a significant association between the IL-1alpha-889 T/T genotype and AD (OR=3.022, 95% CI: 1.001-9.119) was found, whereas no difference was found in the group from the USA. Results were also compared with previously published studies that analyzed the same IL-1 polymorphisms in AD. In both groups, the analysis of the estimated haplotypes shows that AD patients and controls who carry the IL-1beta-511 C allele, were also more frequently carriers of the IL-1Ra 1 allele (haplotypes -C-1). The total frequency of the two -C-1 haplotypes (C-C-1 plus T-C-1) was about one half of the total frequency of the eight estimated haplotypes. This was confirmed by significant linkage disequilibrium between these two loci in both the Italian and USA groups. In the Italian group a weak association of the T-C-2 haplotype with the disease (OR=1.648, 95% CI: 1.519-1.788) was also found, whereas in the USA group no difference was found. Although ours and other published data on different samples of Caucasian and non-Caucasian AD show a great heterogeneity in the frequencies of the IL-1alpha-889, the IL-1beta-511 and the IL-1Ra VNTR gene polymorphisms, we confirm the role of the IL-1alpha-889 T/T genotype as a risk factor for sporadic AD, and show the presence of an allelic association between IL-1beta C and IL-1Ra 1 alleles in both the Italian and the USA groups, confirmed by the presence of significant levels of linkage disequilibrium between these two loci. 相似文献
29.
Gabrielle T. Lemire Éliane Beauregard‐Lacroix Philippe M. Campeau Stefan Parent Marjolaine Roy‐Beaudry Dorothée Dal Soglio Andrée Grignon Françoise Rypens Sandrine Wavrant Marie‐Ange Delrue 《American journal of medical genetics. Part A》2020,182(4):664-672
Our objectives were to describe fetal cases of vertebral defects (VD), assess the diagnostic yield of fetal chromosomal analysis for VD and determine which investigations should be performed when evaluating fetal VD. We performed a retrospective chart review for fetuses with VD seen between 2006 and 2015. Cases were identified from CHU Sainte‐Justine's prenatal clinic visits, postmortem fetal skeletal surveys, and medical records. Cases with neural tube defects were excluded. Sixty‐six fetuses with VD were identified at a mean gestational age of 20 weeks. Forty‐seven (71.2%) had associated antenatal anomalies, most commonly genitourinary, skeletal/limb, and cardiac anomalies. Thirteen mothers (19.7%) had pregestational diabetes (95% CI [10.1%–29.3%]). Fifty‐three cases had chromosomal analysis. Three had abnormal results (5.6%): trisomy 13, trisomy 22, and 9q33.1q34.11 deletion. Thirty‐four (51.5%) pregnancies were terminated, one led to intrauterine fetal demise and 31 (46.9%) continued to term. Of 27 children who survived the neonatal period, 21 had congenital scoliosis and 3 had spondylocostal dysostosis. Seven had developmental delay. In conclusion, prenatal evaluation of fetuses with VD should include detailed morphological assessment (including fetal echocardiogram), maternal diabetes screening, and chromosomal microarray if non‐isolated. Our findings provide guidance about management and counseling after a diagnosis of fetal VD. 相似文献
30.
M. Faina V. Billat R. Squadrone M. De Angelis J. P. Koralsztein A. Dal Monte 《European journal of applied physiology》1997,76(1):13-20
Using 23 elite male athletes (8 cyclists, 7 kayakists, and 8 swimmers), the contribution of the anaerobic energy system to the time to exhaustion (t lim) at the minimal exercise intensity (speed or power) at which maximal oxygen uptake (V˙O2 max) occurs (I V˙O2 max) was assessed by analysing the relationship between the t lim and the accumulated oxygen deficit (AOD). After 10-min warming up at 60% of V˙O2 max, the exercise intensity was increased so that each subject reached his I V˙O2max in 30?s and then continued at that level until he was exhausted. Pre-tests included a continuous incremental test with 2?min steps for determining the I V˙O2max and a series of 5-min submaximal intensities to collect the data that would allow the estimation of the energy expenditure at I V˙O2max . The AOD for the t lim exercise was calculated as the difference between the above estimation and the accumulated oxygen uptake. The mean percentage value of energy expenditure covered by anaerobic metabolism was 15.2 [(SD 6)%, range 8.9–24.1] with significant differences between swimmers and kayakists (16.8% vs 11.5%, P≤0.05) and cyclists and kayakists (16.4% vs 11.5%, P≤0.05). Absolute AOD values ranged from 26.4?ml?·?kg?1 to 83.6?ml?·?kg?1 with a mean value of 45.9 (SD 18)?ml?·?kg?1. Considering all the subjects, the t lim was found to have a positive and significant correlation with AOD (r?=?0.62, P≤0.05), and a negative and significant correlation with V˙O2 max (r?=??0.46, P≤0.05). The data would suggest that the contribution of anaerobic processes during exercise performed at I V˙O2max should not be ignored when t lim is used as a supplementary parameter to evaluate specific adaptation of athletes. 相似文献