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71.
Tani H Tada Y Sasai K Baba E 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(5):461-467
To eradicate canine babesiosis in epidemic areas, mass-screening of the infection situation of Babesia gibsoni including occult infection is necessary. The development of cost-effective method for storage and transport of blood samples is required. A highly efficient DNA extraction procedure from dried blood spots (DBS) onto Whatman 3MM filter paper was developed for the diagnosis of B. gibsoni infection in dog by PCR. In 3 extraction methods, Chelex-based method in combination with saponin washing and phenol-chloroform-isoamyl alcohol extraction (Saponin-PCI method) provided the best results. Sensitivity of the 4 previously described PCR methods for detection of B. gibsoni infection was also compared using serially diluted blood samples of B. gibsoni-infected dogs. The PCR method using Gib599F/Gib1270R primer pair provided the best performance. To evaluate the stability of DNA in DBS, DBS of B. gibsoni-infected dogs stored at room temperature for 2 months. The stability was superior to whole blood samples stored at -20 degrees C for 2 months. This highly efficient DNA extraction method on DBS using Whatman 3MM filter paper has potential to be cost-effective and high performance tool for storage, and molecular diagnosis of clinical blood sample from dog. This procedure in combination with the PCR method using Gib599F/Gib1270R primer pair may greatly assist in diagnosis of B. gibsoni infection in dog populations that are geographically distant. 相似文献
72.
Yoshitaka Kanaoka Daichi Kuniyoshi Eri Inada Yohei Koide Yoshihiro Okamoto Hideshi Yasui Yuji Kishima 《Plant methods》2018,14(1):102
Background
To investigate plant hybrid sterility, we studied interspecific hybrids of two cultivated rice species, Asian rice (Oryza sativa) and African rice (O. glaberrima). Male gametes of these hybrids display complete sterility owing to a dozen of hybrid sterility loci, termed HS loci, but this complicated genetic system remains poorly understood.Results
Microspores from these interspecific hybrids form sterile pollen but are viable at the immature stage. Application of the anther culture (AC) method caused these immature microspores to induce callus. The segregation distortion of 11 among 13 known HS loci was assessed in the callus population. Using many individual calli, fine mapping of the HS loci was attempted based on heterozygotes produced from chromosome segment substitution lines (CSSLs). Transmission ratio distortion (TRD) from microspores was detected at 6 of 11 HS loci in the callus population. The fine mapping of S1 and S19 loci using CSSLs revealed precise distances of markers from the positions of HS loci exhibiting excessive TRD.Conclusions
We demonstrated that AC to generate callus populations derived from immature microspores is a useful methodology for genetic study. The callus population facilitated detection of TRD at multiple HS loci and dramatically shortened the process for mapping hybrid sterility genes.73.
Quantifying landscape pattern and ecosystem service value changes in four rapidly urbanizing hill stations of Southeast Asia 总被引:1,自引:0,他引:1
Context
Hill stations are known for their favorable cool climate and natural environments which generate valuable ecosystem services that benefit the local population, tourists and visitors. However, rapid urbanization threatens the sustainability of these highly valued fragile landscapes.Objectives
We aim to characterize and quantify the changes in the landscape patterns and ecosystem service values (ESVs) of Baguio (Philippines), Bogor (Indonesia), Dalat (Vietnam), and Pyin Oo Lwin (Myanmar), and discuss their implications to landscape sustainability.Methods
We used remote sensing imagery to map land-use/cover (2001 and 2014), and spatial metrics and gradient analysis to characterize the changes in landscape pattern. We employed a benefit transfer method to estimate the changes in ESV and human-to-ESV ratio. A land-change model was used to simulate different scenarios of future built-up expansions (2014–2030).Results
The landscapes of Dalat and Pyin Oo Lwin are becoming more fragmented, while those of Baguio and Bogor are getting more aggregated. Dalat had the highest decrease (absolute change) in ESV and H-ESV ratio, while Bogor had the highest percentage decrease (2001–2014).Conclusions
Rapid urbanization has been a major factor in the landscape transformation of Baguio, Bogor, Dalat and Pyin Oo Lwin. If the current built-up expansion rate will speed up, the decline in future ESV and H-ESV ratio (2014–2030) will be higher than if the rate will continue or slow down. Unless the concept of landscape sustainability is taken seriously in landscape and urban planning, the respective ‘values’ of these precious hill stations will become less and less.74.
The effects of nursery practices on genetic composition and structure were studied inChamaecyparis obtusa by analyzing seeds and one-, two-, and three-year-old seedlings. Enzyme polymorphisms of the6Pgd-2, G6pd, Got, Gk, Shd-2, Pod, Dia-1, andPgm loci were used. OnlyDia-1 indicated significantly different allelic frequencies between seeds and three-year-old seedlings. Most of the genetic diversity
of the parental clones in this seed orchard could be transferred to the offsprings. Genetic diversity on the basis of an average
expected heterozygosity did not differ between seeds and seedlings. A slight excess of homozygotes in seeds and a significant
excess of heterozygotes in seedlings of different ages to the expected panmictic proportions were found. Most of the differences
in genotypic distributions among the seed and seedling stages, probably resulted from viability selection favoring outcrosses,
and selective removal of inbred offsprings including self-fertilized ones prior to their transplantation in the nursery.
A part of this paper was orally presented at the 107th Annual Meeting of the Japanese Forestry Society (1996). 相似文献
75.
Liquid penetration of precompressed wood VI: Anatomical characterization of pit fractures 总被引:3,自引:0,他引:3
Pit fractures of refractory coniferous heartwoods caused by precompression in the radial direction were investigated and are discussed in terms of improved liquid penetration. Small cracks appeared at the boundary between the torus and margo, along the outer margin of the margo, and on the torus when specimens were compressed and deformation was fixed by drying. The remarkable cracks were generally observed for Cryptomeria japonica D. Don. Pseudotsuga menziesii Franco showed peculiar detachment of the torus from the pit border, and Larix leptolepis Gordon exhibited only small cracks on the torus. These fractures patterns were clearer when the precompressed specimens were recovered by water impregnation and then redried.This report was presented at the 46th Annual Meeting of the Japan Wood Research Society, Kumamoto, April 1996 相似文献
76.
Pavarot Noranarttragoon Yuji Ueda Tsutomu Hattori Takashi Matsuishi 《Fisheries Science》2011,77(4):497-502
The yield-per-recruit (YPR) analysis has been used to assess growth overfishing of exploited fish stocks. Since the ex-vessel
price per weight widely depends on the size of the fish, the result of the YPR does not imply the revenue. The value-per-recruit
(VPR) analysis, which is an economic expansion of the YPR analysis, was conducted for bighand thornyhead Sebastolobus macrochir caught off the Pacific coast of northern Honshu, Japan. The results showed that, for the current age at first capture (t
c = 3), the current fishing mortality (F = 0.12) was close to the optimum level. However, for the current F, optimum t
c in the VPR model was 8 years and would lead to a 47% increase compared to the current revenue. The maximum YPR was obtained
at t
c = 6 years, but the revenue at t
c = 6 only gave a 20% increase in the maximum revenue. The difference was caused by the size dependency of the ex-vessel price
per weight. The VPR model would generate fisheries management plans with both economical and biological consideration and
would help in making general consensus of fisheries management strategies. 相似文献
77.
Go Suzuki Wataru Okada Youko Yasutake Sayaka Kai Yuji Fujikura Iwao Tanita Hiroshi Yamashita Takeshi Hayashibara Wataru Ando Koichi Nogami Masayuki Fudo 《Fisheries Science》2018,84(5):849-856
Extremely low post-settlement survival is one of the largest barriers for artificial rehabilitation of Acropora corals. However, little data have been found for interspecific difference of the post-settlement survival probably because the observation of coral juvenile is difficult in the field. Here, we analyzed the survival of three dominant species of Acropora corals (A. digitifera, A. tenuis, A. yongei), with different colony morphologies and habitat preferences, for 2 years after settlement under the same environmental conditions. The post-settlement survival was significantly higher for A. tenuis than for A. digitifera 3 months after settlement. Two years later, the survival rate of A. tenuis was approximately 15 times higher than A. digitifera. In a separate analysis of three bottle-brush species (A. awi, A. echinata, A. subglabra) and A. tenuis, post-settlement survival was always higher for A. awi than for other two bottle-brush species, suggesting that the initial survival was different among morphologically sister species. Low survival was possibly associated with slow growth rates during the first 7 months. Thus, species selection is important for successful artificial coral rehabilitation, with A. tenuis being the most viable option. Alternatively, new techniques are required to improve post-settlement survival of slow growing coral species. 相似文献
78.
79.
It is now widely recognized that probiotics have health-beneficial effects on humans and animals. Probiotics should survive in the intestinal tract to exert beneficial effects on the host's health. To keep a sufficient level of probiotic bacteria in the gastrointestinal tract, a shorter interval between doses may be required. Although adherence to the intestinal epithelial cell and mucus is not a universal property of probiotics, high ability to adhere to the intestinal surface might strongly interfere with infection of pathogenic bacteria and regulate the immune system. The administration of probiotic Lactobacillus stimulated indigenous Lactobacilli and the production of short-chain fatty acids. This alteration of the intestinal environment should contribute to maintain the host's health. The immunomodulatory effects of probiotics are related to important parts of their beneficial effects. Probiotics may modulate the intestinal immune response through the stimulation of certain cytokine and IgA secretion in intestinal mucosa. The health-beneficial effects, in particular the immunomodulation effect, of probiotics depend on the strain used. Differences in indigenous intestinal microflora significantly alter the magnitude of the effects of a probiotic. Specific probiotic strains suitable for each animal species and their life stage as well as each individual should be found. 相似文献
80.
Comparisons among MRI signs,apparent diffusion coefficient,and fractional anisotropy in dogs with a solitary intracranial meningioma or histiocytic sarcoma
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Masae Wada Daisuke Hasegawa Yuji Hamamoto Yoshihiko Yu Aki Fujiwara‐Igarashi Michio Fujita 《Veterinary radiology & ultrasound》2017,58(4):422-432
Although MRI has become widely used in small animal practice, little is known about the validity of advanced MRI techniques such as diffusion‐weighted imaging and diffusion tensor imaging. The aim of this retrospective analytical observational study was to investigate the characteristics of diffusion parameters, that is the apparent diffusion coefficient and fractional anisotropy, in dogs with a solitary intracranial meningioma or histiocytic sarcoma. Dogs were included based on the performance of diffusion MRI and histological confirmation. Statistical analyses were performed to compare apparent diffusion coefficient and fractional anisotropy for the two types of tumor in the intra‐ and peritumoral regions. Eleven cases with meningioma and six with histiocytic sarcoma satisfied the inclusion criteria. Significant differences in apparent diffusion coefficient value (× 10?3 mm2/s) between meningioma vs. histiocytic sarcoma were recognized in intratumoral small (1.07 vs. 0.76) and large (1.04 vs. 0.77) regions of interest, in the peritumoral margin (0.93 vs. 1.08), and in the T2 high region (1.21 vs. 1.41). Significant differences in fractional anisotropy values were found in the peritumoral margin (0.29 vs. 0.24) and the T2 high region (0.24 vs. 0.17). The current study identified differences in measurements of apparent diffusion coefficient and fractional anisotropy for meningioma and histiocytic sarcoma in a small sample of dogs. In addition, we observed that all cases of intracranial histiocytic sarcoma showed leptomeningeal enhancement and/or mass formation invading into the sulci in the contrast study. Future studies are needed to determine the sensitivity of these imaging characteristics for differentiating between these tumor types. 相似文献