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131.
The present study examined the physiological impact of a school based sprint interval training (SIT) intervention in replacement of standard physical education (SPE) class on cardio-respiratory fitness (CRF) and glucose homeostasis during the semester following summer vacation. Participants (n=49) were randomly allocated to either intervention (SIT; n=26, aged 16.9 ± 0.3 yrs) or control group who underwent standard physical education (SPE; n=23, aged 16.8 ± 0.6 yrs). CRF (VO2max) and glucose homeostasis were obtained prior-to and following 7 weeks of SIT exercise. Significant group x time interaction was observed for CRF (P < 0.01) with non-significant trends for fasting insulin (P= 0.08), and HOMA-IR (P=0.06). CRF decreased (P < 0.01) in SPE such that POST intervention CRF was significantly lower (P< 0.05) in SPE. Fasting plasma glucose (P < 0.01), insulin (P< 0.01) and HOMA-IR (P< 0.01) increased significantly amongst SPE. The main finding of the present study is that 7-weeks of SIT exercise is an effective method of maintaining (but not improving) CRF and fasting insulin homeostasis amongst school-going adolescents. SIT exercise demonstrates potential as a time efficient physiological adjunct to standard PE class in order to maintain CRF during the school term.  相似文献   
132.
Following the recent disclosure of 3-methyl pyrrole-2,4-dicarboxylic acid 2-propyl ester 4-(1,2,2-trimethyl-propyl) ester as a potent and selective mGluR1 non-competitive antagonist, the use of a doubly (13)C-labeled analogue to identify, and consequently prevent, metabolically labile positions is reported.  相似文献   
133.
A single copy of bacteriophage T7 DNA polymerase and DNA helicase advance the replication fork with a processivity greater than 17,000 nucleotides. Nonetheless, the polymerase transiently dissociates from the DNA without leaving the replisome. Ensemble and single-molecule techniques demonstrate that this dynamic processivity is made possible by two modes of DNA polymerase-helicase interaction. During DNA synthesis the polymerase and the helicase interact at a high-affinity site. In this polymerizing mode, the polymerase dissociates from the DNA approximately every 5000 bases. The polymerase, however, remains bound to the helicase via an electrostatic binding mode that involves the acidic C-terminal tail of the helicase and a basic region in the polymerase to which the processivity factor also binds. The polymerase transfers via the electrostatic interaction around the hexameric helicase in search of the primer-template.  相似文献   
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Andrew JS Coats 《Trials》2000,1(3):155-6
Chronic heart failure (CHF) is a common condition with a poor prognosis. It is associated with poor exercise tolerance and debilitating symptoms. These symptoms appear to be associated with pathophysiological changes that occur systemically in the patient with CHF. Exercise training in carefully selected patients has been shown to be safe and to improve exercise capacity. Many of the pathophysiological abnormalities of CHF are improved by training. Some studies have suggested a possible improvement in morbidity and mortality with training. This review analyzes the controlled clinical trials of exercise training in CHF published to date.  相似文献   
137.
Three polymerase chain reaction (PCR) techniques were compared to analyse the genetic diversity of Clinacanthus nutans eight populations in the northern region of Peninsular Malaysia. The PCR techniques were random amplified polymorphic deoxyribonucleic acids (RAPD), inter-simple sequence repeats (ISSR) and random amplified microsatellite polymorphisms (RAMP). Leaf genomic DNA was PCR amplified using 17 RAPD, 8 ISSR and 136 RAMP primers . However, only 10 RAPD primers, 5 ISSR primers and 37 RAMP primers produced reproducible bands. The results were evaluated for polymorphic information content (PIC), marker index (MI) and resolving power (RP). The RAMP marker was the most useful marker compared to RAPD and ISSR markers because it showed the highest average value of PIC (0.25), MI (11.36) and RP (2.86). The genetic diversity showed a high percentage of polymorphism at the species level compared to the population level. Furthermore, analysis of molecular variance revealed that the genetic diversity was higher within populations, as compared to among populations of C. nutans. From the results, the RAMP technique was recommended for the analysis of genetic diversity of C. nutans.  相似文献   
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The human cytochrome CYP2A13, which is mainly expressed in the respiratory tract, has been shown to be highly efficient in vitro in the metabolism of tobacco-smoke carcinogens and procarcinogens such as 4-methylnitroso-1-(3-pyridyl)-1-butanone (NNK). In order to investigate the extent of CYP2A13 genetic polymorphism in a French Caucasian population of 102 individuals, a screening for sequence variations in the 5'-untranslated and protein encoding regions of its gene was performed using a polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) strategy. Six polymorphisms in the coding region were identified, including two rare missense mutations (C474G or Asp158Glu, G967T or Val323Leu) and one nonsense mutation (Arg101Stop). This deleterious mutation, the most frequent (5%) in our population, presumably encodes a severely truncated protein. The influence of the nonsense mutation in lung cancer susceptibility was examined by PCR-SSCP using peripheral blood DNA from 204 cases of lung cancer and 201 controls. The CYP2A13*7 allele, which harbours the C301T mutation, was present in 2.0% of controls and 3.4% of cases. However, multivariate analysis showed an elevated risk for small cell lung cancer in subjects heterozygous for the null allele (odds ratio OR=9.9; 95% confidence interval CI=1.9-52.2). This increased risk was not linked to other histological types of lung cancer.  相似文献   
139.
BackgroundThe present investigation aims to determine the chemical structure and protoscolicidal effects of Elettaria cardamomum L. essential oil (ECEO) and its main compounds 1–8 cineole alone and along with albendazole (ALZ) against Echinococcus granulosus protoscoleces in vitro and ex vivo. We also decided to evaluate some cellular mechanisms such as the apoptotic activity and the permeability of plasma membrane of protoscoleces treated with ECEO and 1–8 cineole.MethodsHydatid cyst protoscoleces were divided into seven groups including protoscoleces treated with ECEO 50 µl/mL (T1), protoscoleces treated with ECEO 100 µl/mL (T2), protoscoleces treated with ECEO 200 µl/mL (T3), protoscoleces treated with 1–8 cineole 100 µg/mL (T4), protoscoleces treated with 1–8 cineole 200 µg/mL (T5), protoscoleces treated with 1–8 cineole 100 µg/mL + albendazole 50 µg/mL (T6), and protoscoleces treated with 1–8 cineole 200 µg/mL + albendazole ALZ-50 µg/mL (T7). The viability of protoscoleces were recorded by eosin staining examination. Moreover, the induction of apoptosis and the plasma membrane permeability of the protoscoleces treated with ECEO and 1–8 cineole were evaluated.ResultsThe highest protoscolicidal effect of ECEO was observed at the dose of 200 µl/ml (T3). 1,8-Cineole alone and combined with ALZ, particularly at the dose of 200 µg/ml (T5 and T7), destroyed the 100% protoscolices after 10 min incubation. The ECEO (T1-T3) and 1–8 cineole alone (T4 and T5) and in combination with ALZ (T6 and T7) took longer to display their protoscolicidal effect ex vivo. The obtained results of relative fuorescent items exhibited that the protoscoleces incubated with ECEO and 1,8-Cineole, alter the permeability of plasma membrane by Sytox Green with increasing the concentration. The findings revealed exhibited that ECEO and 1,8-Cineole increasingly and dose-dependently induced activation of caspase-3 enzyme ranging from 6.8 to 23.3%.ConclusionOur obtained results revealed that ECEO and its main compound, 1,8-Cineole exhibited the potent protoscolicidal in vitro and ex vivo; and if more research is done on their efficacy and toxicity in animal models and even clinical setting, it can be suggested as a protoscolicidal agent to use during hydatid cyst surgery.  相似文献   
140.
Oils with high oleic acid content are in great demand because they have optimal properties for food and non-food uses. Two different levels of high oleic acid content (>75 and >84%) have been reported in safflower (Carthamus tinctorius L.). The trait is mainly controlled by partially recessive alleles at a major gene Ol, but the highest levels have been attributed to modifying genes. The objectives of this research were to map the Ol locus and modifying genes involved in oleic acid content of safflower seeds and to determine the nature of Ol through a candidate gene approach. Two F2 mapping populations from the nuclear male-sterile line CL-1 and the high oleic acid lines CR-6 (>75% oleic acid) and CR-9 (>84%) were developed and phenotyped for oleic acid content at the F2 and F3 seed level. A genetic linkage map comprising 15 linkage groups and 116 random amplified polymorphic DNA, simple sequence repeat (SSR), and sequence-characterized amplified regions marker loci was constructed for the CL-1?×?CR-9 population. The Ol gene was mapped to linkage group (LG) T3 tightly linked to the SSR marker ct365, which was confirmed in the CL-1?×?CR-6 population. Additionally, a quantitative trait locus with a minor effect on increasing oleic acid content was identified on LG T2. The candidate gene approach indicated that an oleoyl-phosphatidylcholine desaturase FAD2-1 locus underlies the Ol gene. Both the genetic information and the markers developed in this research will contribute to marker-assisted selection for high oleic acid content in safflower.  相似文献   
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