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排序方式: 共有319条查询结果,搜索用时 31 毫秒
311.
Yanad ABOU MONSEF Osman KUTSAL 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(4):613
Hepatic progenitor cells are periportally resident cells capable of differentiating into mature hepatocytes or cholangiocytes to ensure hepatic regeneration. This reaction is termed a ductular reaction. In the present study, regenerative response of the feline liver to different hepatic diseases was investigated immunohistochemically. Regeneration of the liver through hepatocellular replication and proliferation of progenitor cell compartment were comparatively evaluated. Histological and immunohistochemical stainings were conducted on feline liver samples (n=40) representing various hepatobiliary diseases. Cytokeratin (CK) 7, CK19, Proliferating cell nuclear antigen (PCNA), Ki67, and Human hepatocyte marker 1 (Hep Par-1) were used. The presence of progenitor cells within feline livers was proved, both as passive cells in normal liver and as active cells (ductular reaction) in hepatic lesions. CK7 was found to be a suitable antibody for immunohistochemically detecting feline progenitor cells. In acute events, regeneration was predominantly shaped by the division of hepatocytes. In chronic events and severe acute events, hepatocytes lost their ability to divide and regeneration mainly occurred through progenitor cells. Location of the ductular reaction varied between different hepatic diseases. Parenchymal ductular reaction was detected in fulminant hepatitis, chronic hepatitis, hepatocellular lipidosis and metastatic lymphoma, whereas septal ductular reaction was detected in chronic hepatitis and metastatic lymphoma. Ductular reaction exhibited positive staining for Hep Par-1 in chronic and severe acute events. This study indicates the major role played by hepatic progenitor cells in regeneration of the feline liver. Moreover, it shows how the activation pattern of ductular reaction varies according to the hepatobiliary disease type. 相似文献
312.
313.
Summary The F2's from crosses between Dyfed (S.240; a black grained cultivar) and monosomics of Sun II (non-black cultivar) were analysed. With the exception of F2 progenies involving monosomes, II, VI, VII, X, XI, XII, XIII and XIV, all other deviated from the genetic ratio 3 black: 1 non-black. The cytological examination of the non-black individuals belonging to those families that did not deviate from the 3:1 ratio showed that they were either 41- or 42-chromosome plants. However, non-black individuals involving monosome XIV were 40-chromosome plants. The gene conferring the black colour to the grains in Avena sativa cv. Dyfed (S.240) is located on chromosome XIV.Department of Plant Breeding and Genetics, Sind Agriculture University. Tando Jam. Pakistan. 相似文献
314.
Weyand S Shimamura T Yajima S Suzuki S Mirza O Krusong K Carpenter EP Rutherford NG Hadden JM O'Reilly J Ma P Saidijam M Patching SG Hope RJ Norbertczak HT Roach PC Iwata S Henderson PJ Cameron AD 《Science (New York, N.Y.)》2008,322(5902):709-713
The nucleobase-cation-symport-1 (NCS1) transporters are essential components of salvage pathways for nucleobases and related metabolites. Here, we report the 2.85-angstrom resolution structure of the NCS1 benzyl-hydantoin transporter, Mhp1, from Microbacterium liquefaciens. Mhp1 contains 12 transmembrane helices, 10 of which are arranged in two inverted repeats of five helices. The structures of the outward-facing open and substrate-bound occluded conformations were solved, showing how the outward-facing cavity closes upon binding of substrate. Comparisons with the leucine transporter LeuT(Aa) and the galactose transporter vSGLT reveal that the outward- and inward-facing cavities are symmetrically arranged on opposite sides of the membrane. The reciprocal opening and closing of these cavities is synchronized by the inverted repeat helices 3 and 8, providing the structural basis of the alternating access model for membrane transport. 相似文献
315.
E. E. Babiker E. A. E. El Sheikh A. J. Osman A. H. El Tinay 《Plant foods for human nutrition (Dordrecht, Netherlands)》1995,47(3):257-263
A field investigation of two faba bean cultivars (cv.), Agabat and Silaim, showed that bean yellow mosaic virus (BYMV) infection reduced (p≤0.001) yield (Kg/ha), protein content and in vitro protein digestibility (IVPD) but increased (p≤0.05) tannin content (mg/100 ml). Nitrogen fertilization with viral infection significantly reduced yield and IVPD for cv. Silaim and increased (p≤0.05) protein and tannin contents. Nitrogen fertilization alone was found to increase (p≤0.05) yield, protein and tannin contents but slightly reduced IVPD.Rhizobium inoculation with viral infection significantly decreased yield per unit area, protein content and IVPD, but increased (p≤0.05) tannin content.Rhizobium inoculation alone significantly increased (p≤0.001) yield and tannin content and slightly increased protein content but decreased IVPD. The results indicated that nitrogen fertilization or nitrogen fixation increased yield, protein and tannin contents and decreased IVPD. Viral infection had an adverse effect on yield, protein content and IVPD but had no effect on tannin content. 相似文献
316.
Sabry A. El-Khodery Mitsu Ishii Salama A. Osman Magdy H. Al-Gaabary 《Tropical animal health and production》2009,41(7):1505-1511
The aim of the present study was to carry out comparative therapeutic effect of moxidectin pour on, doramectin and ivermectin
on psoroptes infestation in buffalo. A total of 318 buffalo in 77 small scale herds suspected to have mange mites were examined
clinically and parasitologically. Fifty-three (16.66%) buffalo in 25 herds were recorded to be infested; 51 (16.35%) with
psoroptic mites, and two (0.31%) with chorioptic mites. Buffalo with psoroptic mites were randomly allocated into three groups
(17 buffalo each). First group was treated with moxidectin pour on at a dose rate of 0.5 mg kg-1. The second group received doramectin (200 μg kg-1 twice subcutaneously, 14 days apart). The third group received ivermectin (200 μg kg-1 twice subcutaneously, 14 days apart). Adjunct to each drug, deltamethrin was applied to the surrounding environment twice
at a two week interval. Treatment outcomes of 51 buffalo with psoroptic mites showed that moxidectin pour on and doramectin
had a significant higher effect on mite count reduction (MANOVA, P < 0.01; Walks, Lambda, P < 0.01) and clinical sum scores (MANOVA, P < 0.05; Walks, Lambda, P < 0.05) compared with injectible ivermectin. On clinical level, the number of clinically recovered buffalo in moxidectin
and doramectin treated groups was significantly (P < 0.05) higher than that of ivermectin treated group. The result of the
present study indicated that psoroptic mites are the main cause of mange in buffalo in Lower Egypt. This is the first report
that describes the effect of moxidectin in buffalo. Moxidectin is a good alternative and easily applied drug for treatment
of psoroptes infestation in buffalo. 相似文献
317.
Imad Khan Hafsa Zaneb Saima Masood Saima Ashraf Hafiz F. Rehman Sajid K. Tahir Habib U. Rehman Adnan Khan Raheela Taj Sadeeq U. Rahman Muqader Shah 《The Journal of Poultry Science》2022,59(3):272
The current study aimed to evaluate the efficacy of selenium nanoparticles (SeNPs), combined or loaded with chitosan (COS), in broiler chickens reared under standard management protocols. The parameters under investigation were production performance, organ development, components of the intestinal barrier, and ileal microbial count. Two hundred and forty day-old chicks were raised in five groups, with each group containing eight replicates (n=6/replicate). The control group received a basal diet whereas the other four groups received basal diets supplemented with SeNPs (0.5 mg/kg), COS (200 mg/kg), SeNPs+COS (0.5 mg/kg SeNPs + 200 mg/kg COS), and SeNPs-loaded COS (SeNPs-L-COS) (200 mg/kg) respectively. On day 35, two birds/replicate were sampled to collect the viscera under investigation. The results revealed that dietary inclusion of SeNPs-L-COS increased (p<0.05) the body weight gain and improved (p<0.05) feed conversion ratio. Similarly, SeNPs-L-COS supplementation increased (p<0.05) the small intestinal villus surface area as well as the count of acidic goblet cells and intraepithelial lymphocytes when compared with the control group. Whereas the total goblet cell count was higher (p<0.05) in the small intestines of both the SeNPs+COS and SeNPs-L-COS groups. Microbial analysis of ileal contents also revealed an increase (p<0.05) in Lactobacilli species count with a concurrent decrease (p<0.05) in Escherichia coli count in the SeNPs-L-COS group when compared with the COS and control groups. Based on the results of the current trial, we can conclude that supplementation with SeNPs-L-COS is a superior combination for promoting the gut health and performance of broilers. 相似文献
318.
Raheel Osman Yan Zhu Weixing Cao Zhifeng Ding Meng Wang Leilei Liu Liang Tang Bing Liu 《作物学报(英文版)》2021,(4):889-900
Extreme high-temperature stress (HTS) associated with climate change poses potential threats to wheat grain yield and quality. Wheat grain protein concentration... 相似文献
319.
玛丽帕·吐达洪 阿不都外力·阿布都热依木 孜来古丽·米吉提 卡依尔·玉素甫 马丽艳木·阿木东 艾尼江·尔斯曼 祖母拉提·阿布都热依木 艾尔肯·热合曼 《干旱区研究》2011,28(6):1071-1080
以西昆仑山2个海拔样点的土样为对象,利用(LB和TSA)2种培养基,基于16S rRNA基因序列的系统发育,采用纯培养法对其可培养细菌多样性进行研究。2样点中共分离到91株细菌,分为25个属,52个种。厚壁菌门(Firmicutes)占总菌数的48.75%,放线菌门(Actinobacteria)占36.25%,γ-变... 相似文献