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91.
Tapani Pöyhönen Kari L. Keskinen Arto Hautala Jukka Savolainen Esko Mälkiä 《European journal of applied physiology》1999,80(1):52-56
This study was designed to determine trial-to-trial and day-to-day reproducibility of isometric force and electromyogram activity (EMG) of the knee extensor muscles in water and on dry land as well as to make comparisons between the two training conditions in muscle activity and force production. A group of 20 healthy subjects (12 women and 8 men) were tested three times over 2 weeks. A measurement session consisted of recordings of maximal and submaximal isometric knee extension force with simultaneous recording of surface EMG from the vastus medialis, vastus lateralis and biceps femoris muscles. To ensure identical measurement conditions the same patient elevator chair was used in both the dry and the wet environment. Intraclass correlation coefficients (ICC) and coefficients of variation (CV) showed high trial-to-trial (ICC=0.95–0.99, CV=3.5%–11%) and day-to-day reproducibility (ICC=0.85–0.98, CV=11%–19%) for underwater and dry land measurements of force and EMG in each muscle during maximal contractions. The day-to-day reproducibility for submaximal contractions was similar. The interesting finding was that underwater EMG amplitude decreased significantly in each muscle during maximal (P?0.01–P?0.001) and submaximal contractions (P?0.05–P?0.001). However, the isometric force measurements showed similar values in both wet and dry conditions. The water had no disturbing effect on the electrodes as shown by slightly lowered interelectrode resistance values, the absence of artefacts and low noise levels of the EMG signals. It was concluded that underwater force and EMG measurements are highly reproducible. The significant decrease of underwater EMG could have electromechanical and / or neurophysiological explanations. 相似文献
92.
Plyusnina A Krajinović LC Margaletić J Niemimaa J Nemirov K Lundkvist Å Markotić A Miletić-Medved M Avšič-Županc T Henttonen H Plyusnin A 《Journal of medical virology》2011,83(1):108-114
In Europe, Dobrava-Belgrade (DOBV), Saaremaa (SAAV), and Puumala (PUUV) viruses are known to cause hemorrhagic fever with renal syndrome (HFRS). All three hantaviruses are now found in Croatia. Lung tissue samples of 315 Apodemus mice trapped in 2003-2004 were screened for the presence of hantaviral N-Ag and 20 mice (6.3%) were found either strongly positive or weak/suspected-positive. Partial sequences of hantavirus M and S segments were recovered by RT-PCR from six mice and subjected to (phylo)genetic analysis that revealed the presence of four novel strains of DOBV and one of SAAV. Curiously, one of the newly described DOBV strains was found in Apodemus agrarius mouse, that is, not in the traditional host, A. flavicollis mice, suggesting a spillover event. S segment sequences recovered previously from HFRS cases [Markoti? et al., 2002] were confirmed as DOBV sequences; one of which appeared particularly close to the prototype Slovenian DOBV isolate. Taken together with earlier data on PUUV in Croatia, these results show a co-circulation of three European hantavirus pathogens in this country. So far, not a single SAAV sequence has been recovered from HFRS patients either in Croatia or neighboring Slovenia and Hungary nor in Slovakia suggesting a somewhat lower fequency of acute SAAV infection in humans in this part of Europe than for example in the Baltics. 相似文献
93.
Jesper Lundbom Antti Hakkarainen Sanni Söderlund Jukka Westerbacka Nina Lundbom Marja‐Riitta Taskinen 《NMR in biomedicine》2011,24(3):238-245
Cross‐talk between adipose tissue and liver is disturbed in the metabolic syndrome. Moreover, the relative fatty acid composition of adipose and liver fat is poorly characterized. Long‐TE 1H MRS can determine the unsaturation and polyunsaturation of adipose tissue. The aim of this study was to use long‐TE 1H MRS to determine the composition of liver fat and its relation to adipose tissue composition. Sixteen subjects with increased liver fat (>5%) were recruited for the study. Using TE = 200 ms, we were able to resolve the olefinic (?CH, 5.3 ppm) and water (H2O, 4.7 ppm) resonances in liver spectra and to obtain a repeatable estimate of liver fat unsaturation (coefficient of variation, 2.3%). With TE = 135 ms, the diallylic (?C? CH2? C?, 2.8 ppm) resonance was detectable in subjects with a liver fat content above 15%. Long‐TE 1H MRS was also used to determine the unsaturation in subcutaneous (n = 16) and visceral (n = 11) adipose tissue in the same subjects. Liver fat was more saturated (double bonds per fatty acid chain, 0.812 ± 0.022) than subcutaneous (double bonds per fatty acid chain, 0.862 ± 0.022, p < 0.0004) or visceral (double bonds per fatty acid chain, 0.865 ± 0.033, p < 0.0004) fat. Liver fat unsaturation correlated with subcutaneous unsaturation (R = 0.837, p < 0.0001) and visceral unsaturation (R = 0.879, p < 0.0004). The present study introduces a new noninvasive method for the assessment of the composition of liver fat. The results suggest that liver fat is more saturated than subcutaneous or visceral adipose tissue, which may be attributed to differences in de novo lipogenesis. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
94.
Matti K. Karvonen Ullamari Pesonen Markku Koulu Tomi‐Pekka Tuomainen Matti I.J. Uusitupa Jukka T. Salonen 《American journal of medical genetics. Part A》2000,93(2):117-121
Neuropeptide Y (NPY) plays an important role in the hypothalamic regulation of food intake and energy balance. According to recent findings in animals, NPY also seems to be a potent regulator of alcohol consumption. We used the recently identified Leu(7) to Pro(7) polymorphism in the signal peptide part of NPY to investigate whether the NPY system is associated with alcohol consumption in humans. The subjects (N = 889) were an ethnically homogenous, nonselected population sample of middle‐aged men from Eastern Finland. The gene variant producing Pro(7) substitution was associated with a 34% higher average alcohol consumption, even after adjustment for a number of covariates (P = 0.03). The proportion of heavy drinkers (over 230 g of ethanol/week) was also somewhat higher in this group (13.1% vs. 8.2%, P = 0.10). Our study provides the first evidence that alcohol preference in humans is likely to be regulated by the NPY system. Am. J. Med. Genet. 93:117–121, 2000. © 2000 Wiley‐Liss, Inc. 相似文献
95.
96.
Eira Poikonen Outi Lyytikäinen Veli-Jukka Anttila Irma Koivula Jukka Lumio Pirkko Kotilainen Hannu Syrjälä Petri Ruutu 《BMC infectious diseases》2010,10(1):312
Background
In a previous study we observed an increasing trend in candidemia in Finland in the 1990s. Our aim was now to investigate further population-based secular trends, as well as outcome, and evaluate the association of fluconazole consumption and prophylaxis policy with the observed findings. 相似文献97.
Objectives
To review the literature about oral symptoms and signs at the menopause with an emphasis on hormone replacement therapy (HRT). To give practical guidelines for women and their physicians in menopause-related oral health problems.Methods
The PubMed and Cochrane databases was searched until mid January 2009 with key words such as “menopause”, “menopausal complaints”, “postmenopausal complaints” and “oral diseases”, “oral discomfort”, “dental health”, “dental diseases”, “saliva”, “burning mouth syndrome”, “dry mouth”, “xerostomia”. Because of a scarcity of controlled studies no systematic review could be conducted.Results
Oral discomfort is found in many menopausal women in addition to more general climacteric complaints. The principal peri- and postmenopausal symptoms are dry mouth and burning mouth (glossodynia) which, in turn, may increase the occurrence of oral mucosal and dental diseases, such as candidiasis. The mechanisms of hormone-related oral symptoms and signs are not known although oestrogen receptors, for example, have been detected in the oral mucosa and salivary glands. In principle, the histology of oral and vaginal mucosa is very similar and thus their symptoms might share a common cause. Yet, hormone replacement therapy use does not necessarily prevent or help women with oral symptoms.Conclusion
Properly controlled long-term randomized studies are needed to assess the effect of HRT on oral discomfort. Future gene profiling could identify women who may or may not benefit from HRT with regard to oral symptoms. 相似文献98.
Antti O. Helminen Harri Korhonen Jukka V. Seppl 《Macromolecular chemistry and physics.》2002,203(18):2630-2639
Cross‐linked ε‐caprolactone (CL) and D ,L ‐lactide (DLLA) copolymers with elastic properties were synthesized in three steps. First, the monomers were copolymerized in ring‐opening polymerization to obtain telechelic star‐shaped oligomers with almost completely random monomer distribution. The oligomers were methacrylated with methacrylic anhydride in the second step and cured in a third. Molar CL/DLLA compositions of 30/70, 50/50, 70/30, 90/10, and 100/0 were used to obtain elastic structures with a wide range of properties. The effect of the average length of the copolymer block on the properties of the networks was evaluated with three different co‐initiator contents (0.5, 1.0, and 2.0/100) in the oligomer synthesis. The oligomers were characterized by 13C NMR spectroscopy, size‐exclusion chromatography (SEC), and differential‐scanning calorimetry (DSC). The formation of elastic networks was confirmed by the absence of a flow region in dynamic mechanical analysis (DMA), the increase in Tg in DSC, and the full recovery of the sample dimensions after tensile testing. In addition, gel contents were high and the samples swelled in CH2Cl2. The networks possessed break stresses from 0.7–9.7 MPa with elongations from 80–350%. Networks with 100 or 90% of ε‐caprolactone retained their form in vitro for 12 weeks, but an increase in lactide content made the networks more vulnerable to hydrolysis.
99.
100.
Xiuying Li Shiyan Guo Chunliu Zhu Quanlei Zhu Yong Gan Jukka Rantanen Ulrik Lytt Rahbek Lars Hovgaard Mingshi Yang 《Biomaterials》2013
Chitosan nanoparticles (NC) have excellent capacity for protein entrapment, favorable epithelial permeability, and are regarded as promising nanocarriers for oral protein delivery. Herein, we designed and evaluated a class of core shell corona nanolipoparticles (CSC) to further improve the absorption through enhanced intestinal mucus penetration. CSC contains chitosan nanoparticles as a core component and pluronic F127-lipid vesicles as a shell with hydrophilic chain and polyethylene oxide PEO as a corona. These particles were developed by hydration of a dry pluronic F127-lipid film with NC suspensions followed by extrusion. Insulin nested inside CSC was well protected from enzymatic degradation. Compared with NC, CSC exhibited significantly higher efficiency of mucosal penetration and, consequently, higher cellular internalization of insulin in mucus secreting E12 cells. The cellular level of insulin after CSC treatment was 36-fold higher compared to treatment with free insulin, and 10-fold higher compared to NC. CSC significantly facilitated the permeation of insulin across the ileum epithelia, as demonstrated in an ex vivo study and an in vivo absorption study. CSC pharmacological studies in diabetic rats showed that the hypoglycemic effects of orally administrated CSC were 2.5-fold higher compared to NC. In conclusion, CSC is a promising oral protein delivery system to enhance the stability, intestinal mucosal permeability, and oral absorption of insulin. 相似文献