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991.
Stefanie Kimbacher Ingrid Gerstl Branko Velimirov Sylvia Hagemann 《Molecular genetics and genomics : MGG》2009,282(2):165-172
P transposons belong to the eukaryotic DNA transposons, which are transposed by a cut and paste mechanism using a P-element-coded transposase. They have been detected in Drosophila, and reside as single copies and stable homologous sequences in many vertebrate species. We present the P elements Pcin1, Pcin2 and Pcin3 from Ciona intestinalis, a species of the most primitive chordates, and compare them with those from Ciona savignyi. They showed typical DNA transposon structures, namely terminal inverted repeats and target site duplications. The coding
region of Pcin1 consisted of 13 small exons that could be translated into a P-transposon-homologous protein. C. intestinalis and C. savignyi displayed nearly the same phenotype. However, their P elements were highly divergent and the assumed P transposase from C. intestinalis was more closely related to the transposase from Drosophila melanogaster than to the transposase of C. savignyi. The present study showed that P elements with typical features of transposable DNA elements may be found already at the base of the chordate lineage.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
992.
993.
THE EXPRESSION OF APELIN AND ITS RECEPTOR APJ DURING DIFFERENT PHYSIOLOGICAL STAGES IN THE BOVINE OVARY 总被引:1,自引:0,他引:1
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Stefanie Schilffarth Bernadette Antoni Dieter Schams Heinrich HD Meyer Bajram Berisha 《International journal of biological sciences》2009,5(4):344-350
Recent studies implicate that apelin and its receptor APJ may have important role for the modulation of angiogenesis. The aim of this study was to further characterise the regulation of apelin/APJ system in bovine ovary. Experiment 1: corpora lutea (CL) were assigned to the following stages: days 1-2, 3-4, 5-7, 8-12, 13-16, >18 (after regression) of oestrous cycle and of gravidity (month <3, 3-5, 6-7 and >8). Experiment 2: Follicles during maturation were divided into granulosa cells (GC) and theca interna (TI) and were examined separately. Classification of follicles occurred by follicle size and oestradiol-17β (E2) concentration in the follicular fluid (FF) (<0.5 ng/ml, 0.5-5 ng/ml; 5-40 ng/ml; 40-180 ng/ml; >180 ng/ml). Real-time RT-PCR (qPCR) was applied to investigate mRNA expression of examined factors. In general, the expression level of apelin during the oestrous cycle was significantly higher compared to the one during pregnancy. Apelin mRNA levels were always high during the cycle with a tendency of decrease after CL regression. The APJ mRNA in the CL was significantly up regulated on days 5-7 and 8-12 followed by a decrease on days 13-16, and further on days >18. The expression of APJ does not show any significant regulation in the CL throughout pregnancy. The expression of apelin and APJ was not statistically regulated in GC, but was significantly up regulated in follicles with an E2 concentration of more than 5 ng/ml and showed an increase according to growth and maturation of follicles. In conclusion, our data suggest that apelin/APJ system is involved in the mechanism regulating angiogenesis during follicle maturation as well as during CL formation and function in the bovine ovary. 相似文献
994.
Rembert Koczulla Silvano Dragonieri Robert Schot Robert Bals Stefanie A Gauw Claus Vogelmeier Klaus F Rabe Peter J Sterk Pieter S Hiemstra 《Respiratory research》2009,10(1):78
Background
Analysis of exhaled breath condensate (EBC) is a non-invasive method for studying the acidity (pH) of airway secretions in patients with inflammatory lung diseases.Aim
To assess the reproducibility of EBC pH for two commercially available devices (portable RTube and non-portable ECoScreen) in healthy controls, patients with asthma or COPD, and subjects suffering from an acute cold with lower-airway symptoms. In addition, we assessed the repeatability in healthy controls.Methods
EBC was collected from 40 subjects (n = 10 in each of the above groups) using RTube and ECoScreen. EBC was collected from controls on two separate occasions within 5 days. pH in EBC was assessed after degasification with argon for 20 min.Results
In controls, pH-measurements in EBC collected by RTube or ECoScreen showed no significant difference between devices (p = 0.754) or between days (repeatability coefficient RTube: 0.47; ECoScreen: 0.42) of collection. A comparison between EBC pH collected by the two devices in asthma, COPD and cold patients also showed good reproducibility. No differences in pH values were observed between controls (mean pH 8.27; RTube) and patients with COPD (pH 7.97) or asthma (pH 8.20), but lower values were found using both devices in patients with a cold (pH 7.56; RTube, p < 0.01; ECoScreen, p < 0.05).Conclusion
We conclude that pH measurements in EBC collected by RTube and ECoScreen are repeatable and reproducible in healthy controls, and are reproducible and comparable in healthy controls, COPD and asthma patients, and subjects with a common cold. 相似文献995.
996.
Jay R. Hoffman Nicholas A. Ratamess Christopher P. Tranchina Stefanie L. Rashti Jie Kang Avery D. Faigenbaum 《Amino acids》2010,38(3):771-778
The effect of 42 g of protein ingested pre- and post-exercise on recovery from an acute resistance exercise session was examined
in 15 male strength/power athletes who were randomly divided into a supplement (SUP) or placebo (PL) group. Subjects reported
to the Human Performance Laboratory (HPL) on four separate occasions (T1–T4). Maximal strength [one repetition-maximum (1-RM)]
testing was performed during T1. During T2 subjects performed four sets of ten repetitions at 80% of their 1-RM in the squat,
dead lift and barbell lunge exercises with 90 s of rest between each set. Blood draws occurred at baseline (BL), immediate
and 15 min post-exercise to determine testosterone, cortisol and creatine kinase (CK) concentrations. Subjects reported back
to the HPL 24 (T3) and 48 h (T4) post-exercise for a BL blood draw and to perform four sets of ten repetitions with 80% of
1-RM for the squat exercise only. No differences in the number of repetitions performed in the squat exercise were seen between
the groups at T2. Relative to T2, PL performed significantly (P < 0.05) fewer repetitions than SUP at T3 and T4 (−9.5 ± 5.5 repetitions vs. −3.3 ± 3.6 during T3, respectively, and −10.5 ± 8.2
repetitions vs. −2.3 ± 2.9 repetitions during T4, respectively). No differences in hormonal measures were seen between the
groups. CK concentrations were significantly (P < 0.05) elevated at T3 for both groups, but continued to elevate (P < 0.05) at T4 for PL only. No significant group differences were noted for CK at any time point. Results indicate that a
proprietary protein SUP consumed before and after a resistance training session significantly contributes to improvements
in exercise recovery 24 and 48 h post-exercise. 相似文献
997.
Tjaša Tolar Stefanie Jacomet Anton Velušček Katarina Čufar 《Vegetation History and Archaeobotany》2010,19(1):53-67
This paper presents the first comparable overview of different recovery techniques used for waterlogged Neolithic sediments
in the surroundings of the Alps in the last decades. Such an investigation became necessary because it was not known which
parts of plants and types of remains were absent or completely underrepresented due to inappropriate recovery techniques in
Slovenian archaeobotany up to 2006. During the 2007 excavation of the approximately 5,200 years old Neolithic pile dwelling
site of Stare gmajne, Ljubljansko barje, Slovenia, we compared three methods for the investigation of botanical macroremains: method 1 (M1) included
rough wet-sieving and subsequent drying of the fractions; method 2 (M2) rough wet sieving and keeping the fractions wet; and
method 3 (M3) washing over and keeping the fractions wet. M3 with gentle washing, systematic subsampling, examination, and
sorting of macroremains while wet, as well as using 0.355 mm as the smallest sieve mesh size gave the best results. When using
the cruder M2 or M1 methods, waterlogged uncarbonized seeds of taxa such as Linum usitatissimum, Papaver somniferum and Brassica rapa, waterlogged chaff of Cerealia and pericarps of Maloideae and Quercus sp., which are all fragile, were underrepresented or even completely absent and therefore the plant spectra were strongly biased.
On the contrary, taxa with lignified seed/fruit walls like Cornus mas, Corylus avellana or Rubus sp. were overrepresented when using the M2 and particularly the M1 method. The application of the M3, instead of the M1 method
which has been traditionally used in Slovenian archaeobotany, helped us to identify uncarbonized remains of Linum usitatissimum and various species of Triticum for the first time in a waterlogged Neolithic site in Slovenia. Our study should contribute to a standardization of methods,
which is desperately needed in archaeobotany. The study clearly shows that the plant spectra can be strongly biased if inappropriate
handling techniques are used. The conclusions hold for all kinds of waterlogged sediments of different periods. 相似文献
998.
999.
This study reports body temperature regulation (Tb) and circadian rhythms of undisturbed feral cats in their natural environment in Australia over a continuous period of three months. It furthermore compares these data with Tb data collected of feral cats, after a period of one year in captivity. In free-ranging, undisturbed feral cats, a distinct robust, regular circadian rhythm (strength of rhythm) (21–59.8%) with higher body temperature in the dark (active) phase (mean±STD: 39.2±0.27 °C) and significantly lower body temperature during the light (rest) phase (mean±STD: 38.1±0.47 °C, P<0.001) was found. The acrophase (time of the daily peak) of the three free-ranging cats investigated varied from 22:34 h (LG 2), 22:57 h (LG 1) to 23:17 h (LG 3). In the course of captivity, the cats’ circadian rhythms shifted from nocturnality to a diurnal tendency, with an acrophase ranging from 12:00 h (MtK 2), 12:23 h (MtK 1) to 16:25 h (MtK 3). This change in rhythmicity was accompanied by a significant decrease in robustness (1.7–5.2%) and mean body temperature levels (37.77±0.34 °C) as well as minima and maxima (36–39 °C versus 35.5–41.9 °C, free-ranging cats) of three captive cats, resulting in a significant shift towards a decrease in amplitude. 相似文献
1000.
Nohrdent D Cattaneo C Gabriel P Ohlrogge S Poppa P Schmitt R Tutkuviene J Rizgeliene R Ratnayake M Obertová Z Ritz-Timme S 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》2010,68(1):101-109
Recruiting test persons is crucial in many scientific fields. The recognition of motivators or barriers to survey participation may support the design and recruitment strategy of future studies. The recruitment of under age test persons is very complex and sensitive. This paperpresents and analyses the experiences in recruitment of female juveniles (10-18 years old) in Germany, Italy and Lithuania within the context of an EU funded project concerning the extremely sensitive topic of "child pornography". The purpose of the project was to develop a method for age estimation of juveniles on photographs and videos. The faces of the test persons were photographed and anthropologically measured after an informed consent was signed by their parents and themselves. The analysis of the recruitment strategies and response rates revealed that culturally influenced factors played a significant role in the individual decision for or against a participation in the study. In all countries, the sensitive topic of child pornography had a great influence on the decision process. Many German parents agreed especially in light of this topic while in Italy and Lithuania the word "child pornography" triggered a very negative response. In Germany, the anthropological investigation of the faces provoked negative associations with the anthropometric surveys in the Third Reich. Social and political climate were further relevant factors for decision-making especially in Lithuania. The "top-down" principle of recruitment proved to be very effective for this kind of study. The authorities of headmasters, scientists and institutions positively influenced the decisions of the parents. 相似文献