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排序方式: 共有465条查询结果,搜索用时 31 毫秒
81.
Josep M. Serrano-Ramon Juan M. Cortell-Tormo Iker Bautista Miguel García-Jan Ivn Chulvi-Medrano 《Biology of sport / Institute of Sport》2023,40(1):209
The aim was to compare the acute effects of bench press (BP) and squat (SQ) exercises with blood flow restriction (BFR) (40%, 60%, 80% and 100% of the complete arterial occlusion pressure (AOP)) and without BFR (CON) on the mean propulsive (VelMED) and maximum (VelMAX) bar velocity. Fourteen healthy, physically active males (age, 23.6 ± 4.1 years; height, 1.85 ± 0.11 m; body weight 85.4 ± 4.1 kg) took part in the study. There was one set for each testing condition (CON, 40%, 60%, 80% and 100%) with 6 repetitions for BP and 6 repetitions for SQ, at 60% of 1RM, and 3 minutes of recovery between sets. The results showed statistically significant differences of the sets with 80% BFR vs. CON (mean difference [MD] = 0.035 m · s-1, p < 0.05, ES = 0.52 [1.02–0.03]) and 100% BFR sets vs. CON (MD = 0.074, p < 0.001, ES = 1.08 [1.79–0.38]) for BP. In the SQ exercise, statistically significant differences were found between 100% BFR vs. CON (DM = 0.031 m · s-1, p < 0.05), vs. 100% BFR 40% (MD = 0.04 m · s-1, p < 0.05). Trend analysis showed a statistically significant linear trend (F[1,9] = 34.9, p < 0.001, F[1,13] = 27.32, p < 0.001) for the VelMED in relation to the different levels of BFR. In conclusion, our results showed that BFR levels above ˜80% AOP (BP) and ˜100% AOP (SQ) produce a VelMED improvement at 60% 1RM. 相似文献
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Santiago Royo Tanja Schirmeister Marcel Kaiser Sascha Jung Santiago Rodríguez José Manuel Bautista Florenci V. González 《Bioorganic & medicinal chemistry》2018,26(16):4624-4634
A family of dipeptidyl enoates has been prepared and tested against the parasitic cysteine proteases rhodesain, cruzain and falcipain-2 related to sleeping sickness, Chagas disease and malaria, respectively. They have also been tested against human cathepsins B and L1 for selectivity. Dipeptidyl enoates resulted to be irreversible inhibitors of these enzymes. Some of the members of the family are very potent inhibitors of parasitic cysteine proteases displaying k2nd (M?1s?1) values of seven orders of magnitude. In vivo antiprotozoal testing was also performed. Inhibitors exhibited IC50 values in the micromolar range against Plasmodium falciparum, Trypanosoma brucei, Trypanosoma cruzi and even more promising lower values against Leishmania donovanii. 相似文献
86.
A New Glucose-6-Phosphate Dehydrogenase Variant, G6PD Orissa (44 Ala→Gly), is the Major Polymorphic Variant in Tribal Populations in India 下载免费PDF全文
J. S. Kaeda G. P. Chhotray M. R. Ranjit J. M. Bautista P. H. Reddy D. Stevens J. M. Naidu R. P. Britt T. J. Vulliamy L. Luzzatto P. J. Mason 《American journal of human genetics》1995,57(6):1335-1341
Deficiency of glucose-6-phosphate dehydrogenase (G6PD) is usually found at high frequencies in areas of the world where malaria has been endemic. The frequency and genetic basis of G6PD deficiency have been studied in Africa, around the Mediterranean, and in the Far East, but little such information is available about the situation in India. To determine the extent of heterogeneity of G6PD, we have studied several different Indian populations by screening for G6PD deficiency, followed by molecular analysis of deficient alleles. The frequency of G6PD deficiency varies between 3% and 15% in different tribal and urban groups. Remarkably, a previously unreported deficient variant, G6PD Orissa (44 Ala→Gly), is responsible for most of the G6PD deficiency in tribal Indian populations but is not found in urban populations, where most of the G6PD deficiency is due to the G6PD Mediterranean (188 Ser→Phe) variant. The K of G6PD Orissa is fivefold higher than that of the normal enzyme. This may be due to the fact that the alanine residue that is replaced by glycine is part of a putative coenzyme-binding site. 相似文献
87.
Effect of insectary rearing on host preference and oviposition behavior of the fruit fly parasitoid Diachasmimorpha longicaudata 总被引:1,自引:0,他引:1
Diachasmimorpha longicaudata (Ashmead) has been produced in the laboratory for >160 generations on the larvae of oriental fruit fly, Bactrocera dorsalis (Hendel), the propagation hosts raised routinely on a semi-synthetic wheat diet formulation. Choice tests using modified stinging units were conducted in the laboratory to investigate whether insectary rearing had altered the host seeking and oviposition behavior of female parasitoids. Results showed that fruit fly larvae that developed in papaya, Carica papaya L. var. solo, were less preferred for oviposition than fruit fly larvae that developed on wheat diet when both were exposed concurrently to naive D. longicaudata females (= females without prior oviposition experience). The substrates (pureed papaya or wheat diet) in which treatment larvae were exposed to parasitoids did not affect oviposition preference of gravid D. longicaudata for wheat diet-reared fruit fly larvae. Our study demonstrated the possibility that rearing in an insectary system may have modified the parasitization behavior of female D. longicaudata. 相似文献
88.
Current phylogenetic tree reconstruction methods assume that there is a
single underlying tree topology for all sites along the sequence. The
presence of mosaic sequences due to recombination violates this assumption
and will cause phylogenetic methods to give misleading results due to the
imposition of a single tree topology on all sites. The detection of mosaic
sequences caused by recombination is therefore an important first step in
phylogenetic analysis. A graphical method for the detection of
recombination, based on the least squares method of phylogenetic
estimation, is presented here. This method locates putative recombination
breakpoints by moving a window along the sequence. The performance of the
method is assessed by simulation and by its application to a real data set.
相似文献
89.
We used the repetitive character of transposable elements to isolate a
non-LTR retrotransposon in Drosophila subobscura. bilbo, as we have called
it, has homology to TRIM and LOA elements. Sequence analysis showed a 5'
untranslated region (UTR), an open reading frame (ORF) with no RNA-binding
domains, a downstream ORF that had structural homology to that of the I
factor, and, finally, a 3' UTR which ended in several 5-nt repeats. The
results of our phylogenetic and structural analyses shed light on the
evolution of Drosophila non-LTR retrotransposons and support the hypothesis
that an ancestor of these elements was structurally complex.
相似文献
90.
Cephaleuros virescens is a pantropical subaerial green alga with no known long‐range dispersal mechanisms. Sexual reproduction is relatively rare and may involve intragametangial fusion of identical, mitotically produced gametes. This situation may be a consequence of adaptation to the subaerial habitat. Genetic variation among populations of C. virescens may be very low and might be positively correlated to the distance (hence, time) separating populations. Thus, assessing the global biogeography of C. virescens requires analysis of what might be low levels of variation. Because C. virescens occurs on literally hundreds of different host species, the question of host‐races must also be considered. Preliminary analysis of local populations of C. virescens, originally obtained as field collections from three different host species and subsequently raised in culture, is the first step in addressing the biogeography of this alga. We are using the AFLP plant mapping protocol by PE Applied Biosystems to detect genetic variability in the three isolates of C. virescens. AFLP is a PCR‐based DNA fingerprinting technique that detects the presence or absence of restriction fragments rather than fragment length differences. Because the number of restriction fragments that can be detected with the AFLP technique is “virtually unlimited,” it is a very powerful tool for assessing the degree of relatedness or variability among cultivars or isolates. AFLP techniques have been used successfully to distinguish morphologically identical bacteria, determine relatedness among soybean accessions, reveal genetic variability within bee samples, and identifyfall armyworm strains and hybrids. 相似文献