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1.
In six experimental dogs, arthrographic quality and synovial inflammatory response with shoulder arthrography comparing meglumine-sodium diatrizoate (Urovison) and the monoacidic dimer, meglumine-sodium ioxaglate (Hexabrix) was evaluated. In our study initial films were of equally high diagnostic quality for both contrast media, but delayed films significantly favored ioxaglate for diagnostic quality. The rise in white blood cells in synovial fluid samples collected 24 hours after the arthrographic procedure was significantly lower after the use of ioxaglate. Histologic examination performed 14 days after the intra-articular injection revealed no drug related lesions.  相似文献   
2.
Amplified fragment length polymorphism (AFLP) analysis was used to study genetic variation among 76 isolates of Verticillium. A dendrogram based on the AFLP data revealed three main groups. One group consisted of 35 European isolates derived from Brassica napus together with five Californian isolates taken from B. oleracea. This group displayed a high degree of genetic similarity and included three isolates earlier classified as Verticillium longisporum, indicating that all isolates in this group probably should be regarded as members of V. longisporum. V. dahliae isolates constituted the second group while the third group contained four V. albo-atrum isolates. In addition to these three groups, a cluster of six V. nigrescens isolates was observed. However, the genetic distances between the isolates of V. nigrescens were much higher than those between members in the other groups and the bootstrap value for the V. nigrescens cluster was subsequently low. Four isolates classified as V. tricorpus were highly diverse and did not cluster together. Analysis of molecular variance revealed that the isolates of V. longisporum were separated into four subgroups, based on geographic origin. The study furthermore shows that AFLP is a suitable method for studying population structure in Verticillium.  相似文献   
3.
微管、微丝特异性抑制剂处理对水稻抗病性的影响   总被引:3,自引:0,他引:3  
 微管特异性抑制剂oryzalin、微丝特异性抑制剂细胞松弛素A (cytochalasin A,CA)和细胞松弛素D (cytochalasin D,CD)的试验表明:oryzalin在5~50μmol/L、CA在0.5~1.0μg/mL、CD在1~20μg/mL的浓度范围内,对稻瘟病菌孢子的萌发和附着胞的形成基本上没有影响。采用以上几种细胞骨架特异性抑制剂处理水稻叶鞘都可以不同程度地抑制寄主细胞抗病菌扩展的能力。在抑制剂处理的水稻叶鞘细胞中,病菌扩展的速度加快。进一步的观察发现,抑制剂处理抑制水稻细胞抗病菌的扩展能力与水稻的抗病防卫反应如原生质颗粒化、多酚类物质的积累和HR发生的延迟是相关的。  相似文献   
4.
Rabbit does from R line selected for growth rate present a low reproductive performance and this study aimed to evaluate both the recovery efficacy and viability of recovered embryos after vitrification and the reproductive performance of donor does subjected to in vivo recovery. Does were divided into three groups: 28 does without in vivo recovery (control), 25 does in which in vivo recovery was started in the nulliparous state (group 1) and 30 does with at least one litter before in vivo recovery (group 2). Does were superovulated with a single subcutaneous injection of 50 IU of equine chorionic gonadotropin (eCG) per female, and were then artificially inseminated 60 h later and immediately administered an intravenous dose of 75 IU of human chorionic gonadotropin (hCG) per female. Does from group 1 and 2 were recovered in vivo 76-80 h post-insemination by repeated laparoscopies at one to four times and permitted one or two parturitions between recoveries [in vivo (IV) recovery]. At the end of the experiment, about 16 does of all groups were recovered post-mortem (PM recovery). All normal embryos were vitrified, devitrified and then cultivated in vitro to evaluate the viability after thawing. A significant increase in the ovulation rate was found in does recovered PM than in those recovered IV in the nulliparous state. However, no significant differences were observed in the recovery rate, the donor rate, the number of normal embryos recovered with at least one normal embryo per doe and the viability after thawing between the PM and IV groups. A significant decrease in the fertility rate, total born, live born and weaned kids was found for does from group 1 in comparison with does from group 2. Results support the use of repeated laparoscopy to increase the number of recovered embryos per donor doe especially in such R line does, if they are permitted to produce at least one litter before the beginning of in vivo recovery.  相似文献   
5.
Egg yolk is a common additive to sperm cryopreservation diluents. Because of its animal origin, however, it also represents a potential risk of microbiological contamination in the diluent. This potential contamination can be avoided by using powdered egg yolk, instead of fresh egg yolk, as it is pasteurized. This study was conducted to determine ram sperm cryosurvival was affected by the type of egg yolk used (powdered egg yolk or fresh egg yolk) and by yolk concentration (10, 15 or 20%) in the diluent. Microbiological analyses were also performed to quantify the microbiological contamination in the diluents containing the two types of egg yolk. Sperm cryosurvival was determined by motility and morphology analyses after thawing. Motility parameters were assessed using a computer-assisted sperm analysis (CASA) system, and the percentage of sperm with a normal apical ridge was evaluated using a differential interference contrast microscope. No significant differences were observed between diluents in the percentage of sperm with normal apical ridge. However, higher percentages of total motile cells were observed for samples containing powdered egg yolk (69%) compared to samples containing fresh egg yolk (60%). However, sperm in diluents containing fresh egg yolk, exhibited higher values for average-path velocity, straight-line velocity and beat cross frequency and lower values for amplitude of lateral head displacement (p <0.05), compared to cells in diluents containing powdered egg yolk. Microbiological contamination was similar (<200 CFU/ml) in both diluents, and no bacterial growth was observed in either, when antibiotics were added. Therefore, powdered egg yolk can be effective used in diluents for the freezing of ram semen. However, the in vivo fertility of sperm frozen in diluents containing powdered egg yolk should be tested, as some motility parameters were different for sperm treated with powdered egg yolk compared to fresh egg yolk.  相似文献   
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In recent years, the interest in equine foetal gender determination (FGD) during gestation increased remarkably. Ultrasonographic FGD can be performed in two different periods during gestation. The earliest examination can take place at a gestational age of 60–70 days, whereby the genital tubercle is used to differentiate between male and female foeti. The time window of the second approach is wider (120–210 days), and there are more characteristics to take into consideration. In this article, the feasibility and accuracy of ultrasonographic FGD in mid‐ to late gestation are evaluated. One hundred twenty‐one mares from different breeds with a pregnancy stage between 120 and 270 days were examined once, using B‐scale ultrasonography (Esaote MyLab™ClassC). None of the mares were sedated nor shaved, and the procedure was completed within 15 min. Diagnosis was firstly based on the gonads. The final judgement was made based on all visible foetal reproductive organs. In three cases with a pregnancy stage beyond 257 days, FGD was not possible. All of the examined mares in which a FGD could be performed gave birth to a healthy foal. In 98% of the examinations (116/118), the diagnosis was correctly made. In both cases of misdiagnosis, only one characteristic was seen during the procedure and wrongly interpreted. Beyond 210 days of pregnancy, the extremities can preclude a good visualization of the inguinal region. In conclusion, equine FGD in mid‐ to late gestation is an accessible and accurate technique, although a good ultrasound device is a prerequisite and experience and expertise is necessary.  相似文献   
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Context

‘Conserving Nature’s stage’ has been advanced as an important conservation principle because of known links between biodiversity and abiotic environmental diversity, especially in sensitive high-latitude environments and at the landscape scale. However these links have not been examined across gradients of human impact on the landscape.

Objectives

To (1) analyze the relationships between land-use intensity and both landscape-scale biodiversity and geodiversity, and (2) assess the contributions of geodiversity, climate and spatial variables to explaining vascular plant species richness in landscapes of low, moderate and high human impact.

Methods

We used generalized additive models (GAMs) to analyze relationships between land-use intensity and both geodiversity (geological, geomorphological and hydrological richness) and plant species richness in 6191 1-km2 grid squares across Finland. We used linear regression-based variation partitioning (VP) to assess contributions of climate, geodiversity and spatial variable groups to accounting for spatial variation in species richness.

Results

In GAMs, geodiversity correlated negatively, and plant species richness positively, with land-use intensity. Both relationships were non-linear. In VP, geodiversity best accounted for species richness in areas of moderate to high human impact. These overall contributions were mainly due to variation explained jointly with climate, which dominated the models. Independent geodiversity contributions were highest in pristine environments, but low throughout.

Conclusions

Human action increases biodiversity but may reduce geodiversity, at landscape scale in high-latitude environments. Better understanding of the connections between biodiversity and abiotic environment along changing land-use gradients is essential in developing sustainable measures to conserve biodiversity under global change.
  相似文献   
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