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11.
Horter DC Yoon KJ Zimmerman JJ 《Animal health research reviews / Conference of Research Workers in Animal Diseases》2003,4(2):143-155
The porcine tonsils are a group of lymphoepithelial tissues located at the common openings of the gastrointestinal and respiratory tracts. The tonsils participate in a variety of functions involving innate, cellular and humoral immunity at the local and systemic levels. Among these immunological functions is the continuous surveillance for the presence of foreign antigens at the openings of the gastrointestinal and respiratory tracts. Within the pig, the movement of lymphocytes, cytokines and chemotactic molecules from the tonsils to other lymphoid organs confers immunity to other portals of pathogen entry and facilitates an efficient and rapid systemic immune response. In spite of the immunological nature of the tonsils, some microorganisms have acquired adaptations that allow them to circumvent the tonsillar immune defenses and utilize the tonsils as a site of entry, replication and colonization. Several bacterial and viral pathogens persist asymptomatically within the tonsils, making identification of asymptomatic carrier animals difficult in disease control and/or pathogen elimination. This paper reviews the current information on the anatomy, immunology and pathobiology of porcine tonsils and discusses the tonsils as a site of pathogen entry, replication and colonization using Salmonella spp., classical swine fever virus and porcine reproductive and respiratory syndrome virus as examples. 相似文献
12.
Min-Hee Kang Min-Joo Chae Jang-Won Yoon So-Young Lee Jong-Hyun Yoo Hee-Myung Park 《The Canadian veterinary journal. La revue veterinaire canadienne》2014,55(7):678-682
Resistance to fluoroquinolones and methicillin was determined for 49 ophthalmic isolates of Staphylococcus pseudintermedius from dogs with and without ophthalmic disease. Resistance was observed for ciprofloxacin (40.8%), ofloxacin (38.8%), enrofloxacin (38.8%), levofloxacin (34.7%), and moxifloxacin (4.1%). Eighteen isolates, 16 of which were resistant to oxacillin, were mecA-positive. Nine of the 16 oxacillin-resistant mecA-positive S. pseudintermedius isolates were resistant to more than one fluoroquinolone and 2 isolates were resistant to 5 fluoroquinolones. The frequency of mecA gene occurrence and fluoroquinolone resistance was twice as high among S. pseudintermedius isolates derived from dogs with ophthalmic disease compared with isolates for dogs without ophthalmic disease. The high prevalence of methicillin and fluoroquinolone resistance in S. pseudintermedius from dogs with ophthalmic disease is a concern. 相似文献
13.
Mi-Young Yoon Young Sup Kim Shi Yong Ryu Gyung Ja Choi Yong Ho Choi Kyoung Soo Jang Byeongjin Cha Seong-Sook Han Jin-Cheol Kim 《Pesticide biochemistry and physiology》2011,101(2):118-124
Blast is considered the most important fungal disease of rice due to its wide distribution and destructiveness under favorable conditions. Development of new effective and environmentally benign agents against the causal pathogen, Magnaporthe oryzae, is of great interest. In the course of a search for natural antifungal compounds in medicinal plants, we found that the methanol extract of Angelica gigas roots showed a potent control efficacy against rice blast caused by M. oryzae. We isolated antifungal coumarins from the extract, and they were identified as decursin and decursinol angelate. Antifungal activities of these compounds, along with kasugamycin, were tested on M. oryzae in vivo and in vitro. In an in vivo assay, the three compounds effectively suppressed the development of rice blast at concentrations more than 100 μg/mL. Coumarins showed relatively weak inhibitory effect on fungal mycelial growth when compared to kasugamycin. However, they strongly inhibited M. oryzae spore germination, which was not observed in kasugamycin treatments. This is the first report demonstrating that decursinol angelate can provide control against rice blast and that the two coumarins inhibit M. oryzae spore germination. In addition, the wettable powder formulation of the crude extract of A. gigas prohibited the development of blast symptoms on rice plants more effectively than liquid concentrate formulation of kasugamin, a commercial fungicide. Based on our study, we propose that coumarin compounds as well as the A. gigas root crude extract can be used as natural, benign fungicides for controlling rice blast. 相似文献
14.
Hwang IK Choi JH Li H Yoo KY Kim DW Lee CH Yi SS Seong JK Lee IS Yoon YS Won MH 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(9):965-969
Astrocytes perform neuron-supportive tasks, repair and scarring process in the central nervous system. In this study, we observed glial fibrillary acidic protein (GFAP), a marker for astrocytes, immunoreactivity in the dentate gyrus and hippocampus proper (CA1-3 region) of adult (2-3 years of age) and aged (10-12 years of age) dogs. In the adult group, GFAP immunoreactive astrocytes were distributed in all layers of the dentate gyrus and CA1-3 region, except in the stratum pyramidale of the CA1-3 region. In the aged group, GFAP immunoreactivity decreased markedly in the molecular layer of the dentate gyrus. However, GFAP immunoreactivity in the CA1-3 region increased in all layers, and the cytoplasm of GFAP immunoreactive astrocytes was hypertrophied. GFAP protein levels in the aged dentate gyrus decreased; however, GFAP levels in the CA1-3 region increased. These results suggest that the morphology of astrocytes and GFAP protein levels in the hippocampal dentate gyrus and CA1 region are changed, respectively, with age. 相似文献
15.
Heechun Lee Seongchan Yeon Hyojong Lee Dongwoo Chang Kidong Eom Junghee Yoon Hojung Choi Youngwon Lee 《Veterinary radiology & ultrasound》2005,46(4):317-318
A 7-year-old female Maltese presented for evaluation of severe vomiting. A diagnosis of pylorogastric intussusception was made during ultrasonographic examination. The intussusception spontaneously underwent reduction by the following morning. 相似文献
16.
Jundae Lee Jae Bok Yoon Jung-Heon Han Won Phil Lee Sang Hoon Kim Hyo Guen Park 《Euphytica》2010,173(1):55-61
Genic male sterility (GMS) has long been used as a tool for hybrid seed production in chili pepper (Capsicum annuum L.). We developed DNA markers linked to the GMS ms
3
gene in a segregating population using bulked segregant analysis (BSA) and amplified fragment length polymorphism (AFLP)
techniques. The segregating population was subjected to BSA-AFLP with 512 primer combinations. Three AFLP markers (Eagg/Mccc276, Eagc/Mctt178, and Ecag/Mtgc204) were identified as tightly linked to the ms
3
locus. Among them, we converted the AFLP marker Ecag/Mtgc204 to the cleavage amplified polymorphic sequence (CAPS) marker, named GMS3-CAPS, based on sequencing analysis of internal and
flanking regions for the markers between male-fertile and sterile plants. This marker will be useful for pepper breeding using
the GMS system. 相似文献
17.
Mun Sup Yoon Jeongran Lee Chang Yung Kim Jung Hoon Kang Eun Gi Cho Hyung Jin Baek 《Euphytica》2009,165(1):69-77
Approximately 7,000 accessions of Korean soybean (Glycine max (L.) Merrill) landraces, largely composed of three collections, the Korea Atomic Energy Research Institute’s soybean (KAS),
the Korean Crop Experiment Station’s soybean (KLS) and the Korean Agricultural Development and Technology Center’s soybean
(KADTC) collections, have been conserved at the Rural Development Administration (RDA) genebank in Korea. The accessions within
collections were classified based on their traditional uses such as sauce soybean (SA), sprouted soybean (SP), soybean for
cooking with rice (SCR), and OTHERS. A total of 2,758 accessions of Korean soybean landraces were used to profile and to evaluate
genetic structure using six SSR loci. A total of 110 alleles were revealed by at the six SSR loci. The number of alleles per
SSR locus ranged from 9 to 39 in Satt187 and Satt_074, respectively. The number of alleles ranged from 87 in the KADTC collection
to 96 in the KLS collection, and from 63 in the SCR group to 95 in the SP group. Nei’s average genetic diversity ranged from
0.68 to 0.70 across three collections, and 0.64 to 0.69 across the usage groups. The average between-group differentiation
(G
st) was 0.9 among collections, and 4.1 among the usage groups. The similar average diversity among three collections implies
that the genetic background of the three collections was quite similar or that there were a large number of duplicate accessions
in three collections. The selection from the four groups classified based upon usage may be a useful way to select accessions
for developing a Korean soybean landrace core collection at the RDA genebank. DNA profile information of accessions will provide
indications of redundancies or omissions and aid in managing the soybean collection held at the RDA genebank. The information
on diversity analysis could help to enlarge the genetic diversity of materials in breeding programs and could be used to develop
a core collection. 相似文献
18.
Hong SY Kim JY Ahn HY Shin JH Kwon O 《Journal of agricultural and food chemistry》2012,60(12):3086-3091
Nitric oxide (NO) produced by endothelial nitric oxide synthase (eNOS) is a fundamental regulator of systemic blood pressure. Ginsenosides from Panax ginseng have been investigated in vitro for the molecular and biochemical mechanisms by which they stimulate NO release in vascular endothelial cells; however, little research has been done to confirm the physiological relevance of these in vitro studies. To address this research gap, the effects of a P. ginseng extract rich in ginsenosides from protopanaxatriol on spontaneously hypertensive rats (SHRs) was examined. Ginseng extract administration stimulated nongenomic Akt-mediated eNOS activation, enhanced NO production, improved vessel wall thickening, and alleviated hypertension in SHRs, confirming the physiological relevance of previous in vitro studies with ginsenosides. 相似文献
19.
20.
Shogo Moriya Shunpei Sato Moongeun Yoon Tomonori Azumaya Shigehiko Urawa Akihisa Urano Syuiti Abe 《Fisheries Science》2009,75(2):359-367
More than 1,000 age-identified chum salmon Oncorhynchus keta collected at 23 stations in the Bering Sea and the North Pacific Ocean in June to July 2003 were used to estimate their origin
of stocks using a DNA microarray developed for analyzing the mitochondrial (mt)DNA haplotypes. The observed haplotype distribution
was nearly the same as that reported previously for fish collected in September 2002 and 2003 in the present surveyed areas.
A conditional maximum-likelihood method for estimation of stock compositions indicated that the Japanese stocks mainly distributed
in north central Bering Sea, whereas the Russian stocks were mainly in western Bering Sea. The North American stocks were
abundant in eastern Bering Sea and around the Aleutian Islands. Such an area-specific stock composition was not significantly
different between mature and immature fish. Thus, the combined results of 2 years suggest that the distribution of chum salmon
is nonrandom in the surveyed areas in summer and autumn, and that fish of the same origin migrate together to the same area
irrespective of age. 相似文献