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61.

Background

Angiotensin converting enzyme (ACE) gene contains a polymorphism, consisting of either the presence (I) or absence (D) of a 287 base pair fragment. Deletion (D) is associated with increased circulating ACE (cACE) activity. It has been suggested that the D-allele of ACE genotype is associated with power-oriented performance and that cACE activity is correlated with muscle strength. Respiratory muscle function may be similarly influenced. Respiratory muscle strength in infants can be assessed specifically by measurement of the maximum inspiratory pressure during crying (Pimax). Pressure-time index of the respiratory muscles (PTImus) is a non-invasive method, which assesses the load to capacity ratio of the respiratory muscles.The objective of this study was to determine whether increased cACE activity in infants could be related to greater respiratory muscle strength and to investigate the potential association of cACE with PTImus measurements as well as the association of ACE genotypes with cACE activity and respiratory muscle strength in this population.

Methods

Serum ACE activity was assayed by using a UV-kinetic method. ACE genotyping was performed by polymerase chain reaction amplification, using DNA from peripheral blood. PTImus was calculated as (Pimean/Pimax) × (Ti/Ttot), where Pimean was the mean inspiratory pressure estimated from airway pressure, generated 100 milliseconds after an occlusion (P0.1), Pimax was the maximum inspiratory pressure and Ti/Ttot was the ratio of the inspiratory time to the total respiratory cycle time. Pimax was the largest pressure generated during brief airway occlusions performed at the end of a spontaneous crying effort.

Results

A hundred and ten infants were studied. Infants with D/D genotype had significantly higher serum ACE activity than infants with I/I or I/D genotypes. cACE activity was significantly related to Pimax and inversely related to PTImus. No association between ACE genotypes and Pdimax measurements was found.

Conclusions

These results suggest that a relation in cACE activity and respiratory muscle function may exist in infants. In addition, an association between ACE genotypes and cACE activity, but not respiratory muscle strength, was demonstrated.  相似文献   
62.
The nitrogen fixing Sinorhizobium meliloti possesses two genes, ppiA and ppiB, encoding two cyclophilin isoforms which belong to the superfamily of peptidyl prolyl cis/trans isomerases (PPIase, EC: 5.2.1.8). Here, we functionally characterize the two proteins and we demonstrate that both recombinant cyclophilins are able to isomerise the Suc-AAPF-pNA synthetic peptide but neither of them displays chaperone function in the citrate synthase thermal aggregation assay. Furthermore, we observe that the expression of both enzymes increases the viability of E. coli BL21 in the presence of abiotic stress conditions such as increased heat and salt concentration. Our results support and strengthen previous high-throughput studies implicating S. meliloti cyclophilins in various stress conditions.  相似文献   
63.
This article aims to investigate the stabilization of Pb, Zn, and Cd contained in contaminated soil from a former mining site in Montevecchio, Sardinia, using clinoptilolite-rich tuff from Pentalofos, Evros. The study included (1) batch experiments and their environmental characterization and (2) column experiments. The first tests involved 1-month pot experiments with varying soil-zeolite mixtures, and their evaluation was carried out by standard USEPA leaching tests (TCLP, EPT test, SPLP). Moderate solubility reductions were recorded according to the TCLP (Pb: 38%, Zn: 33%, and Cd: 32%) due to the introduction of competing Na ions in the solution, while the EPT test showed more significant variations (Pb: 55%, Zn: 74%, and Cd: 46%). A major decrease is achieved in both cases by 10% w/w zeolite addition. The study was complemented by column experiments involving soil-zeolite mixtures eluted by CH3COOH solutions (0.003N and 0.05N). The solubility of Pb was reduced by 50 to 60% compared with the control column, thus indicating the considerable selectivity of clinoptilolite for Pb. In addition, Na and Ca measurements in the leachates confirmed that the immobilization of Pb was mainly attributed to ion exchange reactions.  相似文献   
64.
Spatial synchrony in population dynamics has been documented recently across a range of taxa, and a number of hypotheses about the mechanisms driving spatial synchrony and the consequences of this phenomenon for the persistence of populations have emerged. Spatial environmental covariance is one of the principal factors influencing this synchrony on a large scale. However, most studies focus on population abundances, and little evidence exists on the spatial synchrony of demographic parameters. We used a 15-year dataset from two populations of a vulnerable bird species, the Dalmatian Pelican (Pelecanus crispus), to identify local and global environmental factors that cause population synchrony. We show that survival rates were temporally synchronised between the studied populations and that a large part (>50 % for both populations) of this covariation was driven by local environmental conditions. Several components of the North Atlantic Oscillation index were correlated with local climatic conditions, but not all of these components can be used as informative proxies for future variation in survival. We also present evidence that an individual's future survival can be strongly influenced by the conditions occurring during the early period of its life. Environmental factors such as water level and food availability had similar influences on breeding success and juvenile survival. Juvenile survival was lower during dry years and years of low food availability. This finding indicated that intra-specific competition may act as a limiting factor for species demography, especially in large populations. Estimating the strength of synchrony is important and should be considered in population and metapopulation analyses and in relationship to conservation measures.  相似文献   
65.
66.
ABSTRACT

The current study aims at monitoring, measuring and evaluating the ‘Safe havens for wild birds’ campaign, implemented within the framework of the LIFE programme, in Greece and more specifically in the Ionian Islands. The study detects attitude changes that occurred in three target groups (pupils, local hunters and residents) on three islands where the phenomenon of illegal spring killing is more intense. A questionnaire-based survey was conducted in two phases, just before the launch (2013) and after the completion of the campaign (2015), to enable a comparison of answers and data. The results show that pupils and to a lesser extent residents, enhanced their knowledge and awareness of poaching, the migration of avifauna and the consequences of illegal killing on migratory birds, while this aspect of attitude change was not observed in the hunting community which still believes that spring poaching should be treated as a legal activity and part of local culture.  相似文献   
67.
Background

Tsetse flies (Diptera: Glossinidae) are solely responsible for the transmission of African trypanosomes, causative agents of sleeping sickness in humans and nagana in livestock. Due to the lack of efficient vaccines and the emergence of drug resistance, vector control approaches such as the sterile insect technique (SIT), remain the most effective way to control disease. SIT is a species-specific approach and therefore requires accurate identification of natural pest populations at the species level. However, the presence of morphologically similar species (species complexes and sub-species) in tsetse flies challenges the successful implementation of SIT-based population control.

Results

In this study, we evaluate different molecular tools that can be applied for the delimitation of different Glossina species using tsetse samples derived from laboratory colonies, natural populations and museum specimens. The use of mitochondrial markers, nuclear markers (including internal transcribed spacer 1 (ITS1) and different microsatellites), and bacterial symbiotic markers (Wolbachia infection status) in combination with relatively inexpensive techniques such as PCR, agarose gel electrophoresis, and to some extent sequencing provided a rapid, cost effective, and accurate identification of several tsetse species.

Conclusions

The effectiveness of SIT benefits from the fine resolution of species limits in nature. The present study supports the quick identification of large samples using simple and cost effective universalized protocols, which can be easily applied by countries/laboratories with limited resources and expertise.

  相似文献   
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