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排序方式: 共有2221条查询结果,搜索用时 234 毫秒
961.
Hwang IK Yoo KY Li H Park OK Lee CH Choi JH Kwon DY Won MH 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(9):1005-1010
In this study, we investigated changes in glutamic acid decarboxylase 67 (GAD67) immunoreactivity and its protein levels in the gerbil somatosensory cortex after ischemia/reperfusion. GAD67 immunoreactivity was significantly increased in layers III and V of the somatosensory cortex 12 hr after ischemia/reperfusion. Thereafter, GAD67 immunoreactivity was decreased with time after ischemia/reperfusion. GAD67 immunoreactivity in the somatosensory cortex 4 days after ischemia/reperfusion was similar to that in the sham-operated group. In addition, GAD67 protein levels were also significantly increased 12 hr after transient forebrain ischemia. These results suggest that the transient increase of GAD67 immunoreactivity in layers III and V may be associated with responses to transient ischemia-induced neuronal damage. 相似文献
962.
Hyun-Kyu Park Woori Jo Hyun-Ji Choi Sungwoong Jang Jae-Eun Ryu Hyo-Ju Lee Hyojin Lee Hyejin Kim Eun-Sil Yu Woo-Chan Son 《Journal of veterinary science (Suw?n-si, Korea)》2016,17(1):45-51
Drug-induced liver injury (DILI) is a significant threat to patient health and a major concern during drug development. Recently, multiple circulating microRNAs (miRNAs) have been reported to be potential biomarkers for DILI. To adapt and validate miRNAs for clinical use, we investigated the time-course changes in miR-122 expression levels in an acetaminophen-induced liver injury model in rats. In addition, miR-155 and miR-21 were evaluated as makers of inflammation and regeneration, respectively, to characterize liver status. Our results revealed that miR-122 is an early and sensitive biomarker of hepatocellular injury at a stage when alanine transaminase, aspartate transaminase, and total bilirubin were not detectable. However, no significant differences in the expression levels of other miRNAs (miR-155 and -21) were observed between treatment and vehicle groups. Collectively, these time-course changes in the expression levels of miRNAs may be useful as markers for clinical decision-making, in the diagnosis and treatment of DILI. 相似文献
963.
Ahmed glaucoma valve implantation with Ologen® Collagen Matrix for the surgical treatment of feline glaucoma
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Kang‐hyo Park Joon‐Young Kim Seoung‐woo Choo Hun‐young Yoon Soon‐wuk Jeong 《Veterinary ophthalmology》2018,21(1):96-100
An Ahmed valve implantation with an Ologen® Collagen Matrix (Ologen® CM, Aeon Astron, Leiden, the Netherlands) was performed for the treatment of uncontrolled glaucoma in a cat. This cat was a 5‐year‐old castrated Russian Blue male with a 12‐week history of conjunctival hyperemia and mydriasis of the left eye. During the ophthalmic examination, the intraocular pressure (IOP) oculus sinister (OS) was 52 mmHg, and a narrow iridocorneal angle (ICA) was detected by gonioscopy. Medical treatment with Cosopt® (2% dorzolamide and 0.5% timolol) failed to decrease the IOP. The left eye still had vision, and an Ahmed valve implantation was performed. During the gonioimplantation, Ologen® CM was used to inhibit scar formation around the valve. Following the operation, the IOP was stable at an approximate average of 15 mmHg during the 7‐month follow‐up period, and vision in the left eye was retained without medication. An adequate subconjunctival filtering bleb was formed after 140 days. This is the first case report in which an Ahmed valve gonioimplant with an Ologen® CM has been used for the surgical treatment of glaucoma in a cat. 相似文献
964.
Expression of the glutamine metabolism‐related proteins glutaminase 1 and glutamate dehydrogenase in canine mammary tumours
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J.‐E. Ryu H.‐K. Park H.‐J. Choi H.‐B. Lee H.‐J. Lee H. Lee E.‐S. Yu W.‐C. Son 《Veterinary and comparative oncology》2018,16(2):239-245
Glutamine metabolism is an important metabolic pathway for cancer cell survival, and there is a critical connection between tumour growth and glutamine metabolism. Because of their similarities, canine mammary carcinomas are useful for studying human breast cancer. Accordingly, we investigated the correlations between the expression of glutamine metabolism‐related proteins and the pathological features of canine mammary tumours. We performed immunohistochemical and western blot analysis of 39 mammary tumour tissues. In immunohistochemical analysis, the expression of glutaminase 1 (GLS1) in the epithelial region increased according to the histological grade (P < .005). In the stromal region, complex‐type tumours displayed significantly higher GLS1 intensity than simple‐type tumours. However, glutamate dehydrogenase expression did not show the same tendencies as GLS1. The western blot results were consistent with the immunohistochemical findings. These results suggest that the expression of GLS1 is correlates with clinicopathological factors in canine mammary tumours and shows a similar pattern to human breast cancer. 相似文献
965.
Min Hee Park Jung Im Yun Eunsong Lee Seung Tae Lee 《Reproduction in domestic animals》2019,54(11):1497-1500
A previous study found that undifferentiated porcine spermatogonial stem cells (SSCs) did not adhere to tenascin C, indicating that the integrin α9 and β1 subunits are inactive on the surface of porcine SSCs. However, that study used recombinant tenascin C without FNIII‐like repeats. Therefore, this study re‐evaluated the existence of integrin α9β1 actively functioning on the plasma membrane of porcine SSCs using full‐length native tenascin C with FNIII‐like repeats. The localization and function of the integrin heterodimer were confirmed using immunocytochemistry, attachment and antibody inhibition assays. In undifferentiated porcine SSCs with integrin α9β1 on the cell surface, adhesion to native tenascin C was significantly higher compared with cells lacking native tenascin C and functional blocking of integrin α9β1 significantly inhibited the attachment to native tenascin C compared with no functional blocking. Accordingly, we confirmed that the integrin α9 and β1 subunits function as an active heterodimer on the surface of porcine SSCs in the undifferentiated state. 相似文献
966.
Hong Jo Lee Kyung Je Park Kyung Youn Lee Yongxiu Yao Venugopal Nair Jae Yong Han 《畜牧与生物技术杂志(英文版)》2019,(2)
Background: Previously, we showed that targeted disruption of viral receptor genes in avian leukosis virus(ALV)subgroups using clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9))-based genome editing confers resistance to ALV subgroups B and J. Here, we used the same strategy to target the receptor expressed by ALV subgroup A(TVA) and generate chicken cells resistant to infection by this virus.Results: CRISPR/Cas9-based disruption of exon 2 within the tva gene of DF-1 fibroblasts conferred resistance to infection by ALV subgroup A regardless of whether frameshift mutations were introduced during editing. Conversely,overexpression of the wild-type TVA receptor(wtTVA) by tva-modified DF-1 clones restored susceptibility to ALV subgroup A. The results confirm that exon 2, which contains the low-density lipoprotein receptor class A domain of TVA, is critical for virus entry. Furthermore, we sequentially modified DF-1 cells by editing the tva, tvb, and Na~+/H~+ exchange 1(chNHE1) genes, which are the specific receptors for ALV subgroups A, B, and J, respectively.Conclusions: Simultaneous editing of multiple receptors to block infection by different subgroups of ALV confirmed that ALV subgroups A, B, and J do not share host receptors. This strategy could be used to generate cells resistant to multiple viral pathogens that use distinct receptors for cell entry. 相似文献
967.
Transgenesis and genome editing in birds are based on a unique germline transmission system using primordial germ cells(PGCs), which is quite different from the mammalian transgenic and genome editing system. PGCs are progenitor cells of gametes that can deliver genetic information to the next generation. Since avian PGCs were first discovered in nineteenth century, there have been numerous efforts to reveal their origin, specification, and unique migration pattern, and to improve germline transmission efficiency. Recent advances in the isolation and in vitro culture of avian PGCs with genetic manipulation and genome editing tools enable the development of valuable avian models that were unavailable before. However, many challenges remain in the production of transgenic and genome-edited birds,including the precise control of germline transmission, introduction of exogenous genes, and genome editing in PGCs.Therefore, establishing reliable germline-competent PGCs and applying precise genome editing systems are critical current issues in the production of avian models. Here, we introduce a historical overview of avian PGCs and their application, including improved techniques and methodologies in the production of transgenic and genome-edited birds, and we discuss the future potential applications of transgenic and genome-edited birds to provide opportunities and benefits for humans. 相似文献
968.
Evaluation of a Biofloc System for Intensive Culture of Fathead Minnows,Pimephales promelas
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Jeonghwan Park Luke A. Roy Nilima Renukdas Trevor Luna 《Journal of the World Aquaculture Society》2017,48(4):592-601
This study was carried out to test the suitability of biofloc technology to improve the productivity of the fathead minnow, Pimephales promelas, a commercially important baitfish in North America. Biofloc growth was induced in treatment tanks by periodic additions of a carbon source (glucose) to maintain a C : N ratio of 12:1. Control tanks (no aeration and no carbon addition) accommodated densities equivalent to 1 million fish/ha, while treatment tanks (biofloc) had densities of 1, 2, 4, and 8 million fish/ha. Fish were fed 4% body weight using a 32% protein commercial diet. There were no significant differences in condition of fish harvested from control and treatment densities (P < 0.05). However, fish growth indicators such as final individual weight, feed conversion efficiency, and specific growth rate were significantly impaired at higher stocking densities. Survival rate was significantly lower in the 8 million/ha treatment (P < 0.05). Results were indicative of possible production efficiencies of twofold higher in biofloc systems stocked at or below 4 million/ha compared with traditional ponds. Although biofloc systems maintained the desired water‐quality parameters, biofloc microbial biomass did not seem to significantly enhance feed conversion and specific growth rates of fathead minnows. 相似文献
969.
Azohydroxypyridone disperse dyes containing a fluorosulfonyl group were dyed on PET/cotton blends and their dyeing and fastness
properties were investigated. Specially, the azohydroxypyridone dyes containing a nitro group in place of the fluorosulfonyl
group in the para position to azo group were synthesized in order to compare their dyeing and fastness properties on PET/cotton blends with
those of fluorosulfonyl-substituted analogues. As these dyes can be alkali cleared in the same bath, a one-bath dyeing method
was used and the results were compared with that of a conventional two-bath dyeing method. In particular, the cross-staining
of cotton was studied in order to assess their suitability for the one-bath dyeing of PET/cotton blends. 相似文献
970.
Jong Shin Park Yong-Chan Chung Sang Do Lee Jae Whan Cho Byoung Chul Chun 《Fibers and Polymers》2008,9(6):661-666
The shape memory polyurethane (PU) copolymers cross-linked by celite, a porous inorganic material with enormous surface area
and hydroxyl groups on the surface, were prepared to see if the shape memory effect and the mechanical properties were improved.
The PU copolymers with different celite contents were compared and characterized by IR, DSC, DMA, and UTM. The melting temperatures
of PU soft segment were around 20 oC independent of celite content. The shape memory effect and mechanical properties were
dependent on the celite content, and the celite addition into the reaction mixture should be made in the middle of polymerization
to get the best shape memory and mechanical properties. The best mechanical properties were found at 0.2 wt% celite content
and its shape retention rate went up to 98 %. The inclusion of celite as a cross-linker increased both shape memory effect
and mechanical properties. The reasons underlining the improvements by adopting celite as a cross-linker are discussed in
this paper. 相似文献