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21.
The results of a serological survey of livestock in Kazakhstan, carried out in 1997–1998, are reported. Serum samples from 958 animals (cattle, sheep and goats) were tested for antibodies to foot and mouth disease (FMD), bluetongue (BT), epizootic haemorrhagic disease (EHD), rinderpest (RP) and peste des petits ruminants (PPR) viruses, and to Brucella spp. We also investigated the vaccination status of livestock and related this to changes in veterinary provision since independence in 1991. For the 2 diseases under official surveillance (FMD and brucellosis) our results were similar to official data, although we found significantly higher brucellosis levels in 2 districts and widespread ignorance about FMD vaccination status. The seroprevalence for BT virus was 23%, and seropositive animals were widespread suggesting endemicity, despite the disease not having being previously reported. We found a few seropositives for EHDV and PPRV, which may suggest that these diseases are also present in Kazakhstan. An hierarchical model showed that seroprevalence to FMD and BT viruses were clustered at the farm/village level, rather than at a larger spatial scale. This was unexpected for FMD, which is subject to vaccination policies which vary at the raion (county) level.  相似文献   
22.

Background  

Complex Regional Pain Syndrome type one (CRPS I) or formerly Reflex Sympathetic Dystrophy (RSD) is a disabling syndrome, in which a painful limb is accompanied by varying symptoms. Neuropathic pain is a prominent feature of CRPS I, and is often refractory to treatment. Since gabapentin is an anticonvulsant with a proven analgesic effect in various neuropathic pain syndromes, we sought to study the efficacy of the anticonvulsant gabapentin as treatment for pain in patients with CRPS I.  相似文献   
23.
The Volta River delta developed as an asymmetric lobe in a tectonic offset on the coast of Ghana. The delta comprises a large curvilinear spit that widens in its central portion due to the adjunction of successive sandy beach ridges. The appearance of a distinct spit, in lieu of a continuous barrier from the present mouth of the Volta River to the Bight of Benin coast, may be an outgrowth of a natural change in the location of the mouth of the Volta. The spit marks a segmentation of the unique sand drift cell that hitherto prevailed on this bight coast. Spit growth has been accompanied by a wave of erosion over the last century of the immediate downdrift sector of the bight coast, endangering the town of Keta. Erosion since the 1960s may have been aggravated by the construction of the Akosombo hydropower dam. The tip of the spit has recently welded to the shoreline, thus assuring resumption of sand supply from the Volta towards the rest of this formerly sand-starved sector of the bight coast. Blocking of sediment by the Akosombo Dam is, in due course, likely to become the overarching factor in delta shoreline stability.  相似文献   
24.
To evaluate the receiver operating characteristics (ROC) to determine the cutoffs of waist circumference as a potential population directed screening tool for hypercholesterolaemia (≥6.5 mmol/L), low high density lipoprotein cholesterol (<0.9 mmol/L), and hypertension (treated and/or systolic ≥160 and/or diastolic blood pressure ≥95 mmHg), in 2183 men and 2698 women aged 20 to 59 years selected at random from Dutch civil registries. Main outcome measures: Height, weight, body mass index (BMI), waist circumference, total plasma cholesterol and high density lipoprotein cholesterol concentrations, and blood pressure. Results: ROC curves showed that sensitivity equalled specificity at waist circumferences between 93–95 cm in men and 81–84 cm in women for identifying individual risk factors, and 92 cm in men and 81 cm in women for identifying those with at least one risk factor. Sensitivity and specificity were equal at levels between 61% to 69% for identifying individual risk factors, with positive predictions (56.8% in men and 37.8% in women) within 2% of those using previously defined ‘Action Level 1’ of waist circumference 94 cm in men and 80 cm in women (58.8% in men and 37.4% in women). Risk prediction by anthropometric methods was relatively low: ROC areas for identifying each risk factor by waist varied from 55% to 60%, and reached about 65% for identifying at least one risk factor. Height accounted for less than 03% of variance in waist circumference. Using BMI at 25 kg/m2 gave similar prediction to waist, but its combination with waist did not improve predictive values. Conclusions: Measurement of waist circumference ‘Action Level 1’ at 94 cm (37 inches) in men and 80 cm (32 inches) in women could be adopted as a simpler valid alternative to BMI for health promotion, to alert those at risk of cardiovascular disease, and as a guide to risk avoidance by self-weight management  相似文献   
25.
26.

Aims

The readily available global rock phosphate (P) reserves may be depleted within the next 50–130 years warranting careful use of this finite resource. We develop a model that allows us to assess a range of P fertiliser and soil management strategies for Barley in order to find which one maximises plant P uptake under certain climate conditions.

Methods

Our model describes the development of the P and water profiles within the soil. Current cultivation techniques such as ploughing and reduced till gradient are simulated along with fertiliser options to feed the top soil or the soil right below the seed.

Results

Our model was able to fit data from two barley field trials, achieving a good fit at early growth stages but a poor fit at late growth stages, where the model underestimated plant P uptake. A well-mixed soil (inverted and 25 cm ploughing) is important for optimal plant P uptake and provides the best environment for the root system.

Conclusions

The model is sensitive to the initial state of P and its distribution within the soil profile; experimental parameters which are sparsely measured. The combination of modelling and experimental data provides useful agricultural predictions for site specific locations.
  相似文献   
27.
Codakine is a new Ca(2+)-dependent mannose-binding C-type lectin (MBL) isolated from the gill tissue of the tropical clam, Codakia orbicularis. Bioinformatic analyses with the BLAST program have revealed similarities with marine lectins involved in immunity whose three-dimensional (3D) structures were unknown up until recently. In this article, we present bioinformatic analyses of marine lectins that are homologous to codakine, in particular lectins from the sea worm Laxus oneistus, named mermaid. These lectins are involved in the symbiotic association with sulphur-oxidizing bacteria which are closely related to the C. orbicularis gill symbiont. Using homology modelling, folding that is characteristic of C-type lectins was observed in all the marine Ca(2+)-dependent lectins studied, with conservation of random coiled structures of the carbohydrate recognition domain (CRD) and Ca(2+)-binding sites. Like codakine, the marine lectins analysed contain a signal peptide commonly found in secreted and transmembrane proteins. The majority of the predictive 3D models established from the lectins exhibit a common feature, namely the involvement in invertebrate and vertebrate immunity (dendritic cell receptor, macrophage receptor, etc.). These bioinformatic analyses and the literature data support the hypothesis that codakine, like the L. oneistus mermaids, is probably involved in the cellular mediation of symbiosis and defence against pathogenic microorganisms.  相似文献   
28.
This work relates to the characterisation of the predominant gill protein of the white clam, Codakia orbicularis (Linné, 1758), which harbours endosymbiotic sulphur-oxidising chemoautotrophic bacteria. Total RNA was extracted from the clam to perform 3'rapid amplification of cDNA ends (3'RACE) using degenerate oligonucleotides prepared from a partial sequence of a predominant protein of about 14kDa, termed codakine. The partial peptide sequence was obtained by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) and Edman degradation. Clones isolated from the cDNA library and containing the gene of interest were used in polymerase chain reaction (PCR). The PCR and RACE-PCR products were sequenced to determine the entire coding DNA sequence of codakine. BLAST analysis revealed about 23% to 29% sequence identity between codakine and various animal C-type lectins that are often involved in symbiosis and immune defences. Codakine also contains the motifs and domains of Ca(2+)-dependent C-type lectins, and in particular the tripeptide EPN motif frequently found in mannose-binding lectins (MBLs). Analysis of the protein by affinity chromatography on a mannose-agarose column is consistent with the findings that codakine is a dimeric Ca(2+)-dependent MBL of about 29kDa. Based on the present results, it is hypothesised that this novel C. orbicularis gill protein is involved in the recognition of symbiotic and pathogenic bacteria.  相似文献   
29.
30.

Background  

E. coli O157 is a bacterial pathogen that is shed by cattle and can cause severe disease in humans. Phage type (PT) 21/28 is a subtype of E. coli O157 that is found across Scotland and is associated with particularly severe human morbidity.  相似文献   
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