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1.

Background

Campylobacteriosis is a zoonotic disease, and animals such as poultry, pigs and cattle may act as reservoirs for Campylobacter spp. Cattle shed Campylobacter spp. into the environment and they can act as a reservoir for human infection directly via contact with cattle or their faeces or indirectly by consumption of contaminated food. The aim of this study was to determine the prevalence, the quantitative load and the genetic strain diversity of Campylobacter spp. in dairy cattle of different age groups.

Results

Faecal samples of 200 dairy cattle from three farms in the central part of Lithuania were collected and examined for Campylobacter. Cattle herds of all three farms were Campylobacter spp. positive, with a prevalence ranging from 75% (farm I), 77.5% (farm II) to 83.3% (farm III). Overall, the highest prevalence was detected in calves (86.5%) and heifers (86.2%). In contrast, the lowest Campylobacter prevalence was detectable in dairy cows (60.6%). C. jejuni, C. coli, C. lari and C. fetus subsp. fetus were identified in faecal samples of dairy cattle. C. upsaliensis was not detectable in any sample. The high counts of Campylobacter spp. were observed in faecal material of dairy cattle (average 4.5 log10 cfu/g). The highest numbers of Campylobacter spp. were found in faecal samples from calves (average 5.3 log10 cfu/g), whereas, faecal samples from cows harboured the lowest number of Campylobacter spp. (average 3.7 log10 cfu/g). Genotyping by fla A PCR-RFLP analysis of selected C. jejuni isolates showed that some genotypes were present in all farms and all age groups. However, farm or age specific genotypes were also identified.

Conclusions

Future studies are needed to investigate risk factors related to the degree of colonisation in cattle. Based on that, possible measures to reduce the colonisation and subsequent shedding of Campylobacter in cattle could be established. It is important to further investigate the epidemiology of Campylobacter in the cattle population in order to assess associated risks to public health.
  相似文献   
2.
Studies have linked the use of corporal punishment of children to the development of mental health disorders. Despite the recommendation of international governing bodies for a complete ban of the practice, there is little European data available on the effects of corporal punishment on mental health and the influence of laws banning corporal punishment. Using data from the School Children Mental Health Europe survey, the objective of this cross-sectional study was to examine the prevalence and legal status of corporal punishment across six European countries and to evaluate the association between parental use of corporal punishment and children’s mental health. The study found that odds of having parents who reported using occasional to frequent corporal punishment were 1.7 times higher in countries where its use is legal, controlling for socio-demographic factors. Children with parents who reported using corporal punishment had higher rates of both externalized and internalized mental health disorders.  相似文献   
3.
Probiotic encapsulation is an entire system that not only involves but also depends on many factors. Elements such as the encapsulation method itself, materials, environmental conditions, and last, but not least, the strain; all play an important role in the encapsulation process. The current paper focuses on the right selection of probiotics, the various stress factors that impact the survival capacity of probiotics during and after encapsulation, and the rational selection of appropriate protection strategies to overcome these factors and achieve the highest possible encapsulation efficiency under optimal conditions. This review discusses the effects of temperature, moisture content, and water activity as well as pH, oxygen, and pressure on the viabilities of microorganisms. The effect of the surface and structure of the capsules on the encapsulated microorganisms and the impact of the materials used for the encapsulation are discussed as well. Last, but not least, the importance of choosing the right bacteria is reviewed.  相似文献   
4.
Human activities generate waste, whose amounts tend to increase as the demand for quality of life becomes greater and greater. Hazardous waste (HW) generally makes up only about 1% of all waste in Europe; nevertheless, it presents a serious risk to the ecosystem and human health unless managed and treated safely. Several countries of the European Union (EU) report treatment rates of HW in excess of 40%; the others export a large portion of it. Notwithstanding that lots of efforts have been made to properly identify, treat, recycle, store, transport, and dispose of HW, this is still a hot topic faced by the governments of many EU countries. The objective of this article is to present a sustainable indicators system to assist in the implementation of a modern and sustainable hazardous waste management (HWM) system in Lithuania. The specific goals are (1) to promote the development of a comprehensive monitoring and enforcement system for timely implementation of HWM rules and other related pieces of legislation and (2) to assist in the implementation of training and awareness of the programs of HWM in support of the development of background data for policy making, including improvement of a hazardous waste identification scheme. The emphasis is put on preventing future discharges of HW by promoting the actions that will result in avoidance, recycling, or recovery of the otherwise hazardous waste.  相似文献   
5.
Changes in plasmalemma K+Mg2+-ATPase dephosphorylating activity and H+ transport were examined in freezing-tolerant and non-tolerant genotypes of the perennial grass species Festuca pratensis Huds. Enzyme activity and ΔμH+ were measured in plasmalemma fractions isolated from basal nodes and roots. Three types of experiments were undertaken: (i) a field experiment, utilizing the seasonal growth and cessation cycle of a perennial plant; (ii) a cold acclimation experiment in hydroponics; and (iii) an instant freezing test. A specific fluctuation in K+Mg2+-ATPase activity was found throughout the seasonal growth of the plants (i). The K+Mg2+-ATPase activity peaks for both the basal node and the root plasmalemma were determined early in the spring before the renewal of growth. The lowest activity values in roots occurred at the time approaching flowering, and in basal nodes at the transition into the growth cessation. The K+Mg2+-ATPase activity was approximately 50% lower in the basal node plasmalemma of freezing-tolerant plants than of non-tolerant ones, when assessed at the optimal growth stage in hydroponics. In hydroponics (ii) and in the freezing test (iii), temperature stress was followed by a more pronounced change in the level of K+Mg2+-ATPase activity than in that of H+ transport, and this change was more clearly differentiated in the basal node plasmalemma of contrasting genotypes than in the roots. Stress response was manifested differently in freezing-tolerant and non-tolerant plants at cold acclimation (4–2 °C) and at freezing (−8 °C) temperatures. Proton transport regulation via coupled changes in the hydrolysed ATP/transported proton ratio, as an attribute of freezing-tolerant plants, is discussed.  相似文献   
6.

Background

2D strain imaging of the left atrium (LA) is a new echocardiographic method which allows us to determine contractile, conduit and reservoir functions separately. This method is particularly useful when changes are subtle and not easily determined by traditional parameters, as it is in arterial hypertension and atrial fibrillation (AF). The aims of our study were: to determine LA contractile, conduit and reservoir function by 2D strain imaging in patients with mild arterial hypertension and paroxysmal AF; to assess LA contractile, conduit and reservoir functions’ relation with LV diastolic dysfunction (DD) parameters.

Methods

LA contractile, conduit and reservoir functions together with echocardiographic signs of LV DD were assessed in 63 patients with arterial hypertension and paroxysmal AF. Patients were grouped according to number of signs showing LV DD (annular e’ velocity: septal e’?<?7 cm/s, lateral e’?<?10 cm/s, average E/e’ ratio?>?14, LA volume index >?34 ml/m2, peak tricuspid regurgitation velocity?>?2.8 m/s) present. Number of patients with 0 signs – 17, 1 sign – 26, 2 signs – 19. Contractile, conduit and reservoir functions were compared between the groups.

Results

Mean contractile, conduit and reservoir strains in all the patients were???14.14 (± 5.83) %, 15.98 (± 4.85) % and 31.03 (± 7.64) % respectively. Contractile strain did not differ between the groups. Conduit strain was higher in patients with 0 signs compared with other groups (p =?0.016 vs 1 sign of LV DD and p =?0.001 vs 2 signs of LV DD). Reservoir strain was higher in patients with 0 signs compared with other groups (p =?0.014 vs 1 sign of LV DD and p <?0.001 vs 2 signs of LV DD).

Conclusions

The patients with paroxysmal AF and primary arterial hypertension have decreased reservoir, conduit and pump LA functions even in the absence of echocardiographic signs of LV DD. With increasing number of parameters showing LV DD, LA conduit and reservoir functions decrease while contractile does not change. LA conduit and reservoir functions decrease earlier than the diagnosis of LV DD can be established according to the guidelines in patients with primary arterial hypertension and AF.
  相似文献   
7.

Objective

To ascertain patterns of parental smoking in the vicinity of children in Eastern and Western Europe and their relation to Tobacco Control Scale (TCS) scores.

Methods

Data on parental smoking patterns were obtained from the School Child Mental Health Europe (SCMHE), a 2010 cross-sectional survey of 5141 school children aged 6 to 11 years and their parents in six countries: Germany, Netherlands, Lithuania, Romania, Bulgaria and Turkey ranked by TCS into three level categories toward tobacco control policies.

Results

A slightly higher proportion of Eastern compared to Western European mothers (42.4 vs. 35.1%) were currently smoking in but the difference was not statistically significant after adjusting for maternal age and maternal educational attainment. About a fifth (19.3%) and a tenth (10.0%) of Eastern and Western European mothers, respectively, smoked in the vicinity of their children, and the difference was significant even after adjustment for potential confounders (p<0.001). Parents with the highest educational attainment were significantly less likely to smoke in the vicinity of their children than those with the lowest attainment. After control of these covariates lax tobacco control policies, compared to intermediate policies, were associated with a 50% increase in the likelihood of maternal smoking in the vicinity of children adjusted odds ratio (AOR) = 1.52 and 1.64. Among fathers, however, the relationship with paternal smoking and TCS seems more complex since strict policy increases the risk as well AOR = 1,40. Only one country, however belongs to the strict group.

Significance

Tobacco control policies seem to have influenced maternal smoking behaviors overall to a limited degree and smoking in the vicinity of children to a much greater degree. Children living in European countries with lax tobacco control policies are more likely to be exposed to second hand smoking from maternal and paternal smoking.  相似文献   
8.
Ethephon and Aventrol were used as tools to provoke the processes taking part in the formation of rape seed yield and quality. Investigations on spring rape (Brassica napus L.) cultivars ‘Terra’ and ‘Landmark’ were carried out from 2008–2010. Ethephon (10 mM) and Aventrol (1 l/ha — pinolene 960 g/l) were used on different plant growth stages: BBCH-62–64 and BBCH-72–74, BBCH-80–82, respectively. Impact of ethephon manifested itself as activation of ethylene evocation by siliqua and a slight activation of growth of siliqua dehiscence zone. Siliqua cell plasmalemma and tonoplast H+-ATPases activation under the influence of ethephon occurred but did not lead to the destruction of transmembrane electrochemical potential. Extra seed yield and crude fat yield increased; tendency towards a lowering of the saturated/unsaturated fatty acid ratio was observed. Under the influence of Aventrol the dehiscence zone of siliqua was more closed when compared to the control and the ethephon treated variants, seed loss was significantly lowered and transmembrane cation transport was not damaged. The seed yield increased, and this was due to the accumulation of extra crude fat. Aventrol did not change the fatty acid content in rape seed oil. The positive impacts of ethephon and Aventrol for spring rape seed yield formation and possible mechanisms are discussed.  相似文献   
9.
The aim of this work was to examine H+-ATPase hydrolytic activity and the stability of transmembrane electrochemical gradients in membrane vesicles isolated from seedlings and leaf cells of an invasive Washington lupine (Lupinus polyphyllus Lindl.) and compare them with non-invasive yellow lupine (Lupinus luteus L.). Temperatures of 25 and 30°C, keeping in mind possible climate warming, were used. For harder stress conditions, short term cold treatment (?8°C in vivo) was used. Plasmalemma-, tonoplast-, and endoplasmic reticulum-enriched membrane fractions were obtained from a sucrose density gradient and identified. Differences in ATPase hydrolytic activity were significant only between lupine species and were more obvious in plasmalemma-enriched fractions. Preincubation of seedlings and leaves at ?8°C for 15 min to 24 h showed that microsomic fraction membranes of invasive lupine were more stable (according to Na+-diffusive potential) at low temperature compared to yellow lupine ones. The level of transmembrane electrochemical potential, mainly evoked by ATP-dependent active proton transport, was almost equal in both lupine species. Supposedly, the cells of invasive lupine are able to maintain transmembrane electrochemical potential by the employment of lower hydrolytic activity of H+-ATPase, thus saving energy for growth.  相似文献   
10.
GABAergic interneurons (INs) in the dorsal lateral geniculate nucleus (dLGN) shape the information flow from retina to cortex, presumably by controlling the number of visually evoked spikes in geniculate thalamocortical (TC) neurons, and refining their receptive field. The INs exhibit a rich variety of firing patterns: Depolarizing current injections to the soma may induce tonic firing, periodic bursting or an initial burst followed by tonic spiking, sometimes with prominent spike-time adaptation. When released from hyperpolarization, some INs elicit rebound bursts, while others return more passively to the resting potential. A full mechanistic understanding that explains the function of the dLGN on the basis of neuronal morphology, physiology and circuitry is currently lacking. One way to approach such an understanding is by developing a detailed mathematical model of the involved cells and their interactions. Limitations of the previous models for the INs of the dLGN region prevent an accurate representation of the conceptual framework needed to understand the computational properties of this region. We here present a detailed compartmental model of INs using, for the first time, a morphological reconstruction and a set of active dendritic conductances constrained by experimental somatic recordings from INs under several different current-clamp conditions. The model makes a number of experimentally testable predictions about the role of specific mechanisms for the firing properties observed in these neurons. In addition to accounting for the significant features of all experimental traces, it quantitatively reproduces the experimental recordings of the action-potential- firing frequency as a function of injected current. We show how and why relative differences in conductance values, rather than differences in ion channel composition, could account for the distinct differences between the responses observed in two different neurons, suggesting that INs may be individually tuned to optimize network operation under different input conditions.  相似文献   
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