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61.
Lott ME Hogeman CS Vickery L Kunselman AR Sinoway LI MacLean DA 《American journal of physiology. Heart and circulatory physiology》2001,281(4):H1734-H1741
We examined the effects of dynamic one-legged knee extension exercise on mean blood velocity (MBV) and muscle interstitial metabolite concentrations in healthy young subjects (n = 7). Femoral MBV (Doppler), mean arterial pressure (MAP) and muscle interstitial metabolite (adenosine, lactate, phosphate, K(+), pH, and H(+); by microdialysis) concentrations were measured during 5 min of exercise at 30 and 60% of maximal work capacity (W(max)). MAP increased (P < 0.05) to a similar extent during the two exercise bouts, whereas the increase in MBV was greater (P < 0.05) during exercise at 60% (77.00 +/- 6.77 cm/s) compared with 30% W(max) (43.71 +/- 3.71 cm/s). The increase in interstitial adenosine from rest to exercise was greater (P < 0.05) during the 60% (0.80 +/- 0.10 microM) compared with the 30% W(max) bout (0.57 +/- 0.10 microM). During exercise at 60% W(max), interstitial K(+) rose at a greater rate than during exercise at 30% W(max) (P < 0.05). However, pH increased (H(+) decreased) at similar rates for the two exercise intensities. During exercise, interstitial lactate and phosphate increased (P < 0.05) with no difference observed between the two intensities. After 5 min of recovery, MBV decreased to baseline levels after exercise at 30% W(max) (4.12 +/- 1.10 cm/s), whereas MBV remained above baseline levels after exercise at 60% W(max) (Delta19.46 +/- 2.61 cm/s; P < 0.05). MAP and interstitial adenosine, K(+), pH, and H(+) returned toward baseline levels. However, interstitial lactate and phosphate continued to increase during the recovery period. Thus an increase in exercise intensity resulted in concomitant changes in MBV and muscle interstitial adenosine and K(+), whereas similar changes were not observed for MAP or muscle interstitial pH, lactate, or phosphate. These data suggest that K(+) and/or adenosine may play an active role in the regulation of skeletal muscle blood flow during exercise. 相似文献
62.
Chilingarian LI Preobrazhenskaia LA 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》2006,56(5):629-640
Instrumental defensive (avoidance/escape) and alimentary responses (reinforced with palatable food) in dogs were conditioned by the same stimulus (6-Hz light flashes). Differential inhibition for these responses (0.6-Hz flashes) was formed in unalterable series. Later on, alternative experiments with choice between reinforcements were carried out. In both of experimental series, the degree of alimentary excitability (hunger, satiation) was changed. Numbers of responses to differential and positive conditioned stimuli and their latencies were calculated. Under condition of choice (electrodes on a leg and a pedal in front of a dog) the response depended on a dominant motivation. The dogs differed in the degree of motivation dominance. Differential inhibition was less perfect in unalterable experimental series with dominant motivation. Under conditions of choice between alimentary and defensive reinforcements, the response to the differential stimuli depended on the balance between these motivations: two days of hunger increased the number of alimentary responses, defensive responses prevailed after satiation. 相似文献
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65.
The genetic diversity of 98 potato cultivars of Russian and foreign breeding was studied using of PCR with organelle-specific primers. The polymorphism of both plastid (atpE, trnG/trnK) and mitochondrial (rps, atp6) loci was revealed. Eight different haplotypes were detected in the sample of cultivars studied. Comparatively low of polymorphism of organelle DNA in the potato cultivars was demonstrated: most cultivars (91 or 92.9%) possessed only two haplotypes (I and II); 62 cultivars of them had similar "cultural" cytoplasmic type (haplotype I). The breeding cultivars of the Russian and foreign origin did not differ from each other in frequency of basic haplotypes. 相似文献
66.
van Lenteren JC Ruschioni S Romani R van Loon JJ Qiu YT Smid HM Isidoro N Bin F 《Arthropod Structure & Development》2007,36(3):271-276
Location, structure and histology of chemosensilla on the tip of the ovipositor of the parasitoid Leptopilina heterotoma are described based on SEM and TEM studies. Furthermore, we developed a method for recording extracellular action potentials from the gustatory neurons in response to host haemolymph. This method allowed us to record multi-unit recordings from a sensillum occurring singly on the unpaired ovipositor valve. The TEM study of the ovipositor tip revealed the presence of six dendrites, the electrophysiological recordings provided evidence for the activity of three or possibly four gustatory neurons in response to the complex stimulus offered, leaving other taste functions or a mechanoreceptor function open for the remaining neurons. 相似文献
67.
Brandes N Reichmann D Tienson H Leichert LI Jakob U 《The Journal of biological chemistry》2011,286(48):41893-41903
To understand and eventually predict the effects of changing redox conditions and oxidant levels on the physiology of an organism, it is essential to gain knowledge about its redoxome: the proteins whose activities are controlled by the oxidation status of their cysteine thiols. Here, we applied the quantitative redox proteomic method OxICAT to Saccharomyces cerevisiae and determined the in vivo thiol oxidation status of almost 300 different yeast proteins distributed among various cellular compartments. We found that a substantial number of cytosolic and mitochondrial proteins are partially oxidized during exponential growth. Our results suggest that prevailing redox conditions constantly control central cellular pathways by fine-tuning oxidation status and hence activity of these proteins. Treatment with sublethal H(2)O(2) concentrations caused a subset of 41 proteins to undergo substantial thiol modifications, thereby affecting a variety of different cellular pathways, many of which are directly or indirectly involved in increasing oxidative stress resistance. Classification of the identified protein thiols according to their steady-state oxidation levels and sensitivity to peroxide treatment revealed that redox sensitivity of protein thiols does not predict peroxide sensitivity. Our studies provide experimental evidence that the ability of protein thiols to react to changing peroxide levels is likely governed by both thermodynamic and kinetic parameters, making predicting thiol modifications challenging and de novo identification of peroxide sensitive protein thiols indispensable. 相似文献
68.
Eremina EIu Bondarenko VM Zvereva SI Nikitina OI Shaposhnikova LI 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》2008,(3):62-66
Forty-eight patients with duodenal peptic ulcer disease infected with Helicobacter pylori were examined. All patients undergo conventional 1-week eradication therapy. After its ending the patients were randomized to two groups: those who will be treated by synbiotics or control group. Normoflorin B and Normoflorin L, which contain bifidobacteria or lactobacilli in complex with different microelements, vitamins, aminoacids, organic acids, and antioxidants, were used as synbiotics. Morphologic study of biopsy samples of small intestine mucosa were performed in patients from both groups. It was determined that eradication therapy worsened existing symptoms of dyspepsia in 80.9% of cases or lead to their emergence, connected with dysbiotic manifestations, in 55.5% of patients. Inclusion of synbiotics in complex therapy resulted in rapid and effective elimination of dyspeptic symptoms, promoted recovery of affected morphologic and functional states of small intestine mucosal epithelium, and optimized metabolic processes important for the digestion. 相似文献
69.
Svetoch EA Borzilov AI Eruslanov BV Korobova OV Kombarova TI Levchuk VP Teĭmurazov MG Stepanshin IuG Marinin LI Diatlov IA 《Antibiotiki i khimioterapii͡a》2011,56(9-10):13-18
The therapeutic efficacy of enterocin S760, a broad spectrum antimicrobial peptide produced by Enterococcus faecium LWP760 was tested on mice infected with Bacillus anthracis M-71 to induce anthrax (second Tsenkovsky's vaccine). Intraperitoneal four-, two- or one-fold administration of the peptide in a dose of 25 mg/kg for 10 days for prophylactic (1 hour after the contamination) and therapeutic (24 hours after the contamination) purposes prevented or cured the infection in 90-100% of the mice versus the 100-percent lethality in the control (untreated animals). The antimicrobial activity of enterocin S760 against B. anthracis M-71 in vivo correlated with activity in vitro. Enterocin S760 is considered a novel promising antimicrobial for the treatment of grampositive and gramnegative infections. 相似文献
70.
Deutsch EW Ball CA Berman JJ Bova GS Brazma A Bumgarner RE Campbell D Causton HC Christiansen JH Daian F Dauga D Davidson DR Gimenez G Goo YA Grimmond S Henrich T Herrmann BG Johnson MH Korb M Mills JC Oudes AJ Parkinson HE Pascal LE Pollet N Quackenbush J Ramialison M Ringwald M Salgado D Sansone SA Sherlock G Stoeckert CJ Swedlow J Taylor RC Walashek L Warford A Wilkinson DG Zhou Y Zon LI Liu AY True LD 《Nature biotechnology》2008,26(3):305-312
One purpose of the biomedical literature is to report results in sufficient detail that the methods of data collection and analysis can be independently replicated and verified. Here we present reporting guidelines for gene expression localization experiments: the minimum information specification for in situ hybridization and immunohistochemistry experiments (MISFISHIE). MISFISHIE is modeled after the Minimum Information About a Microarray Experiment (MIAME) specification for microarray experiments. Both guidelines define what information should be reported without dictating a format for encoding that information. MISFISHIE describes six types of information to be provided for each experiment: experimental design, biomaterials and treatments, reporters, staining, imaging data and image characterizations. This specification has benefited the consortium within which it was developed and is expected to benefit the wider research community. We welcome feedback from the scientific community to help improve our proposal. 相似文献