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101.
The vesicular stomatitis virus has an atypical membrane fusion glycoprotein (G) exhibiting a pH-dependent equilibrium between two forms at the virus surface. Membrane fusion is triggered during the transition from the high- to low-pH form. The structure of G in its low-pH form shows the classic hairpin conformation observed in all other fusion proteins in their postfusion conformation, in spite of a novel fold combining features of fusion proteins from classes I and II. The structure provides a framework for understanding the reversibility of the G conformational change. Unexpectedly, G is homologous to gB of herpesviruses, which raises important questions on viral evolution. 相似文献
102.
Lopes P Saucier C Teissedre PL Glories Y 《Journal of agricultural and food chemistry》2006,54(18):6741-6746
Wine bottle aging is extremely dependent on the oxygen barrier properties of closures. Kinetics of oxygen ingress through different closures into bottles was measured by a nondestructive colorimetric method from 0.25 to 2.5 mL of oxygen. After 12, 24, and 36 months of storage, only the control (glass bottle ampule) was airtight. Other closures displayed different oxygen ingress rates, which were clearly influenced by the closure type and were independent of bottle storage position (upright, laid down) for most of the closures tested, at least during the first 24 months of the experiment under controlled conditions. The oxygen ingress rates into bottles were lowest in screw caps and "technical" corks, intermediate in conventional natural cork stoppers, and highest in the synthetic closures. 相似文献
103.
104.
Samoy Y Gielen I Saunders J van Bree H Van Ryssen B 《Veterinary radiology & ultrasound》2012,53(3):236-244
Elbow incongruity is an important factor regarding the treatment and prognosis of elbow dysplasia. Our purpose was to determine the sensitivity and specificity for radiographic detection of elbow incongruity in clinical patients, to establish inter- and intraobserver variation for different parameters, and to evaluate the possibility of radiographic grading of incongruity. Standard radiographic projections were acquired from 29 incongruent and nine congruent elbows of dogs of various ages and breeds. Computed tomography (CT) was used to diagnose and grade the incongruity. All radiographs were evaluated by four observers for detection and grading of elbow incongruity. Sensitivity, specificity, inter- and intraobserver variability were calculated. The mean sensitivity for detection of incongruity was very good (88.8%) with a mean specificity of 91.7%. Correct grading of incongruity was difficult. The radioulnar step and the widening of the humeroulnar and humeroradial joint space were seen most frequently. Intraobserver and interobserver variability were fair to excellent (Kappa = 0.372-0.809), depending on the investigated parameters. Radiography is valuable to screen for elbow incongruity. In over 91% of the patients, a clear distinction could be made between a congruent and an incongruent joint grading was not possible. 相似文献
105.
Objective The in‐vitro validation of a novel Respiratory Ultrasonic Plethysmography (RUP) system designed to detect circumference changes of rib cage and abdominal compartments in large and small animals. Study design Experimental in vitro study. Methods The experimental system includes two compliant fluid‐filled rubber tubes functioning as ultrasonic waveguides. Each has an ultrasonic transmitter and a detector at the opposing ends. Sensor length can be individually adapted in the range of 0.15–2 m. Data are downloaded to a computer at a sampling rate of 10 or 100 Hz. Measurements have a resolution of 0.3 mm. Baseline stability, linearity and repeatability were investigated with dedicated experiments. The base line drift was tested measuring a fixed distance for 2 hours continuously and then 18 hours later. A hand‐operated horse thorax dummy (elliptically shaped, circumference 1.73 m) was used to compare waveforms of RUP with a respiratory inductive plethysmograph (RIP). The electromagnetic interference was tested by approaching metallic objects. Results Baseline drift and repeatability (10 repeated steps of 1.6% and 6.6% elongations and contractions) were within ± 0.3 mm. The response of the system for tube stretching up to 11% of total length was linear with a coefficient of determination for linearity of 0.998. In contrast to RIP, electromagnetic interference could not be observed with RUP. Conclusions and clinical relevance The low baseline drift and the lack of electromagnetic interference favours the use of RUP compared to an RIP device when studying the breathing pattern and end expiratory lung volume changes in conscious and anaesthetized animals. 相似文献
106.
Martina Mosing Dr med vet Diplomate ECVAA Jan M Kuemmerle† Dr med vet Agnes Dadak‡ PhD & Yves PS Moens Dr med vet PhD Diplomate ECVAA 《Veterinary anaesthesia and analgesia》2009,36(3):255-260
Observations A case of a pony with severe cyanide intoxication as a result of cherry ingestion is presented. General anaesthesia was performed for colic surgery. Severe metabolic lactate acidosis in combination with a high arterial oxygen partial pressure and clinically good peripheral perfusion parameters were the remarkable signs during anaesthesia. Severe hypothermia was obvious during recovery. Ten hours post-surgery the pony was euthanized as a result of neurological signs. The diagnosis of cyanide intoxication was made post-mortem.
Conclusion Cherry ingestion can lead to lethal cyanide intoxication in horses indicated by severe nonhypoxic lactic acidosis during anaesthesia. 相似文献
Conclusion Cherry ingestion can lead to lethal cyanide intoxication in horses indicated by severe nonhypoxic lactic acidosis during anaesthesia. 相似文献
107.
The idea that landscape has been created by human activities on a biophysical basis allows for clear cause–effect reasoning.
However, landscape planning and management practice learns that it is impossible to neglect the social perception of landscape,
i.e. the ways people think about nature and landscape. It is the result of social research and human sciences of the last
decade that a differentiation in views of nature and landscape can be identified in the different groups of social actors
in the landscape. Case studies from France and the Netherlands show a marked change in values attributed to nature and landscape
in the end of the last century. Social demand for landscape is growing and a shift from a functional image of nature and landscape
to a more hedonistic image like the Arcadian and wilderness images has taken place. Comparing the Netherlands with France
and rural with urban inhabitants, the influence of urbanisation is evident in this process. It is further shown that images
of nature vary considerably between for example farmers, urban residents, hunters and conservationists. The way people perceive
landscape seems determined by their functional ties with the landscape and the social praxis in which they encounter the landscape.
It is concluded that the concept of landscape is nearer to the lifeworld of people than the abstract notions of nature and
biodiversity. This implies a big challenge both for national and international landscape policies and for local landscape
management initiatives to be developed, taking into due consideration both the material and immaterial nature of landscape. 相似文献
108.
109.
Proteins were extracted from styles of 29 self-incompatible cultivars of almond and separated using non-equilibrium pH gradient
electro-focusing, and the gels were stained for ribonuclease activity. Mutually incompatible cultivars had similar banding
patterns and, for the 24 cultivars already genotyped in France or California, the bands correlated well with the reported
alleles. The band corresponding to S1 of the French labelling system was indistinguishable from that corresponding to Sb of the Californian labelling system, and a controlled cross confirmed that these alleles are identical. The band corresponding
to the Californian Sa was distinct from the bands corresponding to French alleles and, to harmonise the allele labels, it was redesignated S5. The genotypes of five uncharacterised self-incompatible cultivars were inferred from zymograms as follows: ‘Desmayo Largueta’
and ‘Glorieta’, S1S5, ‘Masbovera’, S1S9, ‘Tarragones’, S2S9, and ‘Tokyo’, S6S7. The alleles designated S6 and S9 have not previously been reported. Nine self-compatible cultivars or selections were analysed, and each showed a band corresponding
to an incompatibility allele as well as a common band; however, the correspondence of this common band to Sf, the allele for self-compatibility, is unproven.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
110.
Zoulikha Krimi Aïda Raio Annik Petit Xavier Nesme Yves Dessaux 《European journal of plant pathology / European Foundation for Plant Pathology》2006,116(3):237-246
In the Sidi M’djahed nursery (Algeria), over 60,000 eucalyptus (Eucalyptus occidentalis) plantlets exhibited tumour-like growths localized at the crown of the plants that resembled crown galls caused by Agrobacterium tumefaciens. Bacteria colonizing the galls were isolated and purified. Most (22 out of 24) of the isolates had cultural and biochemical characteristics similar to those of strains of the biovar 1 of A. tumefaciens. Twenty out of 22 Agrobacterium isolates induced tumour formation on various test plants. In PCR experiments, DNA extracted from these virulent strains yielded an amplification signal corresponding to a 247-bp fragment located within the virulence region of nopaline type Ti plasmid. Consistent with this, the opine nopaline was detected in the tumours induced on test plants – but not on eucalyptus plants. Nopaline was degraded by the 20 pathogenic isolates that were also sensitive to agrocin 84, indicating the presence of a nopaline-type pTi in these strains. The chromosomal region encoding the 16S rRNA was analyzed in a sub-population of the pathogenic agrobacterial isolates. The analyzed strains were found to belong to the ribogroup of the reference strain B6. Interestingly, Eucalyptus camaldulensis and Eucalyptus cladocalyx grown in the same nursery and in the same soil substrate developed no galls. 相似文献