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11.
Nociceptive atrophy of the rat soleus muscle induced by bone fracture: a morphometric study 总被引:1,自引:0,他引:1
Zachaová, Gisela, HelenaKnotková-Urbancová, Pavel Hník, andTomá Soukup. Nociceptive atrophy of the rat soleus muscle induced by bone fracture: a morphometric study.J. Appl. Physiol. 82(2): 552-557, 1997.Reflex atrophy of the soleus muscle induced by ipsilateralmetatarsal bone fracture in Sagatal-anesthetized adult male rats wasstudied by using two-dimensional stereological methods 7 days after theoperation. When compared with contralateral solei, the wet weight ofthe experimental soleus muscles was decreased by ~24% and the areaof the entire muscle section by ~29%. In atrophied solei, the numberof type 1 fibers was lower by ~8%, resulting in lower total numberof fibers (by ~6%). This indicates that slow motor units might bemore sensitive to nociceptive stimulation. However, with respect to thefiber area, the reflex atrophy induced by metatarsal bone fracture inthe rat soleus muscle resembles simple atrophy after 7 days, as themean muscle fiber area was decreased by ~26% with no significantdifference between atrophy in type 1 and type 2a fibers (by 27.3 and23.0%, respectively). 相似文献
12.
13.
S. Pavel F.A.J. Muskiet G.T. Nagel Z. Schwippelov J. Ducho 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1981,222(3):329-336
The isolation of two Thormählen-positive compounds from the urine of a patient with malignant melanoma and the elucidation of their structure by gas chromatography—mass spectrometry is described. The compounds were isolated using a poly-N-vinylpyrrolidone column and separated by preparative thin-layer chromatography. After elution they were analyzed by gas chromatography and gas chromatography—mass spectrometry as their trimethylsilyl derivatives and after hydrolysis also as their tert.-butyldimethylsilyl derivatives. The results showed the main Thormählen-positive compound A to be the glucuronide of 5-hydroxy-6-methoxyindole, whereas the minor compound AX appeared to be the glucuronide of its isomer 6-hydroxy-5-methoxyindole. 相似文献
14.
Antonin Pavlok Pavel Trvník Vclav Kope
n
y Jitka astn 《Molecular reproduction and development》1982,6(3):189-197
In the course of in vitro fertilization of zona-free hamster and pig eggs by boar and guinea-pig spermatozoa it was observed that homologous and heterologous eggs fused together, forming cell hybrids between two or more cells. The fusogenic activity was attributed to spermatozoa and this was the hypothesis tested. The fusogenic activity (coinciding with sperm penetration activity) was dependent on the duration of sperm preincubation, which may be regarded as capacitation in vitro. Fusion occurred only after 3 hr of sperm preincubation and a narrow optimum was detected at 4–4.5 hr. Fusion of eggs was also dependent on sperm concentration. A relatively high proportion of fusions was observed at a sperm concentration of 4.0 × 104 per ml and an optimum was attained at a concentration of 5.0 × 105 per ml. The first fusions were observed at 90 min after semination. After 3 hr more than a half of the eggs reacted, and by 20 hr of incubation 80% of ova were fused. The fusability of eggs was tested and found to occur at 14 hr after ovulation. The fusion process was also studied using transmission electron microscopy. It is supposed that the process of egg fusion may be caused either by a similar mechanism to sperm-egg fusion, or by products released during the sperm acrosome reaction. 相似文献
15.
Two new saponins, yuccoside C and protoyuccoside C, have been isolated from the methanolic extract of Yucca filamentosa root and their structures elucidated. Yuccoside C is 3-O-[α-d-galactopyranosyl-(1 → 2)-β-d-glucopyranosyl-(1 → 4)-β-d-glucopyranosyl]-(25S)-5β-spirostan-3β-ol, whereas protoyuccoside C is 3-O-[α-d-galactopyranosyl-(1 → 2)-β-d-glucopyranosyl-(1 → 4)-β-d-glucopyranosyl]-26-O-[β-d-glucopyranosy]-(25S)-5β-furostan-3β,22α,26-triol. 相似文献
16.
Pavel Hrako 《American journal of physical anthropology》1975,43(2):243-244
This paper presents the first data in the alpha-amylase isoenzymes in primates of the families: Lemuridae, Cebidae, Cercopithecidae, Hylobatidae and Pongidae. By means of agar-gel electrophoresis of urine samples from 33 individuals belonging to ten species of the above mentioned families a total of 14 different variants of amylase heterogeneity were found. 相似文献
17.
Josef Trögl Ivana Jirková Petra Zemánková Věra Pilařová Petra Dáňová Jana Pavlorková Pavel Kuráň Jan Popelka Lucie Křiklavová 《Folia microbiologica》2013,58(2):135-140
The content of phospholipid fatty acids (PLFA) was determined in samples of polyvinyl alcohol lenses (Lentikats Biocatalyst, LB) with encapsulated Paracoccus denitrificans withdrawn during long-term denitrification experiments. The total PLFA content correlated highly with specific denitrification activities of LB as well as biomass estimation based on image analyses of microscopic photos. The results confirmed the applicability of PLFA determination for estimation of the amount of living encapsulated microbial biomass during biotechnological applications. 相似文献
18.
Orientation tests performed with Emlen funnels show much variation. This scatter in responses can be partially explained by considering the birds’ personalities.We studied a Passerine migrant, the Sedge Warbler (Acrocephalus schoenobaenus), on autumn passage at Kalimok Biological Station, Bulgaria. Birds caught in the morning were kept in cages with known and regularly controlled amounts of food. In the evening they were tested for orientation, the next morning they were observed for 3 min in an unfamiliar cage, then released.Birds that ate on the first day oriented in the expected, southward direction, non-eating birds were scattered.Eating behaviour was related to the exploration pattern on the next day. Eating birds moved and flew less, hopped, looked around and explored the cage more, and were quicker in eating a food item if present.Lean birds ate and explored more but also oriented better, contrary to expectations where fat reserves indicate readiness for migration. A hypothesis is discussed where fat, migration and personality may be linked.Personality aspects may influence the individuals’ ability to cope with an experimental situation and influence the outcome of the tests, therefore its analysis can help in predicting the birds’ performance in apparently unrelated experiments. 相似文献
19.
Svetlana V. Koltsova Sergei V. Kotelevtsev Pavel Hamet 《Biochemical and biophysical research communications》2009,379(4):1080-1083
Bumetanide and other high-ceiling diuretics (HCD) attenuate myogenic tone and contractions of vascular smooth muscle cells (VSMC) triggered by diverse stimuli. HCD outcome may be mediated by their interaction with NKCC1, the only isoform of Na+, K+, 2Cl− cotransporter expressed in VSMC as well as with targets distinct from this carrier. To examine these hypotheses, we compared the effect of bumetanide on contractions of mesenteric arteries from wild-type and NKCC1 knockout mice. In mesenteric arteries from wild-type controls, 100 μM bumetanide evoked a decrease of up to 4-fold in myogenic tone and contractions triggered by modest [K+]o-induced depolarization, phenylephrine and UTP. These actions of bumetanide were preserved after inhibition of nitric oxide synthase with NG-nitro-l-arginine methyl ester, but were absent in mesenteric arteries from NKCC1-/- mice. The data show that bumetanide inhibits VSMC contractile responses via its interaction with NKCC1 and independently of nitric oxide production by endothelial cells. 相似文献
20.
Katarína Nemjová Jiří Neustupa Jan Št'astný Pavel Škaloud Jana Veselá 《Phycological Research》2011,59(3):208-220
The morphological and molecular differentiation of the Micrasterias truncata (Corda) ex Bréb species complex was investigated. In total, 17 strains traditionally assigned to M. truncata were isolated from different European localities (Czech Republic, southwest France, Ireland), and obtained from public culture collections. In addition, strains of the morphologically similar species, M. decemdentata (Nägeli) W. Archer and M. zeylanica F. E. Fritsch, were also included. Molecular phylogenetic analysis based on trnGucc intron sequences revealed five well supported clades. Two Australian strains assigned to M. truncata var. pusilla G. S. West formed a lineage sister to M. zeylanica. This was evident from a concatenated phylogeny based on small subunit rDNA and trnGucc intron sequences. The isolated position of these strains was also illustrated by parallel landmark‐based geometric morphometric analysis of cell shapes. The strains NIES 783 and NIES 784 probably represent a separate species. Particular analysis, including additional strains, is needed to resolve the relationship inside this lineage. The second phylogenetic lineage, containing two strains of M. truncata var. semiradiata (Kützing) Wolle, was also different from other strains on the basis of morphometric data. We suggest recognizing this variety as a separate species, Micrasterias semiradiata L.A. Brébisson ex F. T. Kützing. The remaining three clades formed a firmly supported group of the ‘core’M. truncata recognized by both molecular markers. However, neither any morphological, morphometric, nor geographical pattern was detected among members of these three clades. This pattern could be caused by a relatively recent origin of these lineages that may represent a sympatric, truly cryptic species. Strains attributable to traditional morphologically defined variety M. truncata var. neodamensis were nested within the ‘core’M. truncata. 相似文献