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排序方式: 共有125条查询结果,搜索用时 15 毫秒
1.
Phan Van Kiem Chau Van Minh Nguyen Tien Dat La Van Kinh Dan Thuy Hang Nguyen Hoai Nam Nguyen Xuan Cuong Hoang Thanh Huong Trinh Van Lau 《Fitoterapia》2010
Phytochemical investigation of the methanol extract of Tinospora cordifolia aerial parts led to the isolation of four new and seven known compounds. The structures of two new aporphine alkaloids, N-formylasimilobine 2-O-β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranoside (tinoscorside A, 1) and N-acetylasimilobine 2-O-β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranoside (tinoscorside B, 2), a new clerodane diterpene, tinoscorside C (3), and a new phenylpropanoid, sinapyl 4-O-β-d-apiofuranosyl-(1 → 6)-O-β-d-glucopyranoside (tinoscorside D, 6) were determined by extensive spectroscopic methods including FTICR-MS and 1D and 2D NMR. 相似文献
2.
固体粉末可以作为乳化剂早在本世紀初就已发现[1]。由于所得的乳浊液一般地讲液滴较粗,稳定性也差,因而长期以来很少被注意。最近L.N.Mukerjee和S.N.Srivastava等人系統地检查了多种难溶无机化合物和粘土作为工业用和农业喷洒用乳化剂的可能性[2,3]。但对于粘土粉末作为乳化剂的条件没有深入研究。本文是研究一定pH范围内几种本国粘土的乳化效能。 相似文献
3.
AH RA LEE MIN SU LEE IN SEONG JUNG DAE YOUNG KIM SANG SEOP NHAM HYUN WOO CHUNG KIDONG EOM 《Veterinary radiology & ultrasound》2010,51(2):145-147
An 8‐year‐old Shih Tzu developed abdominal pain and hyperglobulinemia. A round splenic mass was noted radiographically and sonographically. The patient was evaluated by fluorodeoxyglucose positron emission tomography coupled with computed tomography (FDG‐PET/CT). There was no evidence of metastasis or bone marrow involvement on PET/CT images. The standardized uptake value (SUV) of the splenic mass was increased over the reference range (SUV=4.83). The patient was diagnosed as splenic extramedullary plasmacytoma through immunohistopathologic study. After the splenectomy, the globulin level normalized and the patient is alive without complications. 相似文献
4.
MIN SU LEE JEFF KO AH RA LEE IN HYE LEE MI AE JUNG BRENDA AUSTIN HYUNWOO CHUNG SANGSOEP NAHM KIDONG EOM 《Veterinary radiology & ultrasound》2010,51(2):130-135
The purpose of this study was to assess the effects of four anesthetic protocols on normal canine brain uptake of 2‐deoxy‐2‐[18F]fluoro‐d ‐glucose (FDG) using positron emission tomography/computed tomography (PET/CT). Five clinically normal beagle dogs were anesthetized with (1) propofol/isoflurane, (2) medetomidine/pentobarbital, (3) xylazine/ketamine, and (4) medetomidine/tiletamine–zolazepam in a randomized cross‐over design. The standard uptake value (SUV) of FDG was obtained in the frontal, parietal, temporal and occipital lobes, cerebellum, brainstem and whole brain, and compared within and between anesthetic protocols using the Friedman test with significance set at P<0.05. Significant differences in SUVs were observed in various part of the brain associated with each anesthetic protocol. The SUV for the frontal and occipital lobes was significantly higher than in the brainstem in all dogs. Dogs receiving medetomidine/tiletamine–zolazepam also had significantly higher whole brain SUVs than the propofol/isoflurane group. We concluded that each anesthetic protocol exerted a different regional brain glucose uptake pattern. As a result, when comparing brain glucose uptake using PET/CT, one should consider the effects of anesthetic protocols on different regions of the glucose uptake in the dog's brain. 相似文献
5.
Quadratic fitting was used to regress semen characteristics of 1441 samples consisting of 12‐month collection from 58 Duroc boars against animal age varied from 10 to 80 months. Data was divided into two groups of cool (14.0–22.7°C, RH 81.5%) and hot season (22.9–29.9°C, RH 86.6%), to test effects of age, season and their interactions. Results revealed that young boars of around 1 year old could endure the hot season. The endurance gradually diminished as animals grew. In the hot season animals exhibited peak performance at age around 33 month and it remained for 1 month, while cool‐season kept boars could last for 48 months from 16 months old onward. The reproductive longevity should be 51 month in a subtropical environment and it may extend to 70 month if heat stress can be avoided. The estimated total sperm contribution of a Duroc boar would be 1.8 times more when kept below 22°C than in a natural subtropical environment. It is concluded that to maintain Duroc boars as semen donor to at least 4 years of age is feasible in a subtropical environment and boar longevity could reach 6 years old if well kept in a temperate region. 相似文献
6.
The Firm as Social Networks: An Organisational Perspective 总被引:1,自引:0,他引:1
HENRY WAI‐CHUNG YEUNG 《Growth and change》2005,36(3):307-328
ABSTRACT This paper offers an organizational perspective on the firm in new economic geographies. It starts with the premise of the firm as a production function in neoclassical economics and a cost minimisation device in transaction cost economics. By pointing out the inadequacy in these mainstream economic perspectives on the firm, I draw upon recent behavioral and managerial theories to develop a relational conception of the firm as social networks in which actors are embedded in ongoing power relations and discursive processes. In further elaborating this relational perspective on the firm as an organisational device, I show how the firm is governed through social relations among different actors, how it is a site of contested ideologies and political representations among these actors, and how space and geographical scales matter in shaping its social construction. Taken together, this organisational perspective aims to shift our research agenda in urban and regional development from promoting the growth of the firm per se to understanding how the firm serves as a relational institution that connects spatially differentiated actors in different places and regions. 相似文献
7.
Development of biodegradable films from whey proteins by cross-linking and entrapment in cellulose 总被引:1,自引:0,他引:1
Le Tien C Letendre M Ispas-Szabo P Mateescu MA Delmas-Patterson G Yu HL Lacroix M 《Journal of agricultural and food chemistry》2000,48(11):5566-5575
When cross-linked by heating or by gamma-irradiation and entrapped in cellulose, whey proteins can generate insoluble biofilms with good mechanical properties and high resistance to attack by proteolytic enzymes. Interchain cross-linking of proteins generated an increase in the puncture strength, and a decrease in water vapor permeability. Gelatin was added in film formulation as a stabilizer to improve the puncture strength and film appearance. The structure of the biofilms was also analyzed. SDS-PAGE revealed that heating and gamma-irradiation produce an increase of the molecular weight of the cross-linked protein. Size exclusion chromatography showed a molecular mass of 40 kDa for un-cross-linked whey proteins, whereas for the soluble fractions of the cross-linked proteins, molecular distributions were between 600 and 3800 kDa for the heated proteins and between 1000 and 2000 kDa for gamma-irradiated proteins. No major alteration of the structural conformation of the proteins was observed by FTIR for biofilms obtained after heat treatment, whereas gamma-irradiation induced some modifications in the protein structure. X-ray diffraction analysis suggests that cross-linking by gamma-irradiation seems to modify the conformation of proteins, which became more ordered and more stable. 相似文献
8.
Tien‐Chun WAN Fu‐Yuan CHENG Yu‐Tse LIU Chao‐Ming WANG Ching‐Lin SHYU Chih‐Ming CHEN Liang‐Chuan LIN Ryoichi SAKATA 《Animal Science Journal》2008,79(6):693-698
A novel Bacillus species of Calculus Bovis (cow gallstone) was isolated and identified in this study. Morphological features, bacterial fatty acid analysis using a microbial identification system, carbon source utilization profiles using Biolog system and 16S rDNA sequencing were employed to identify the isolated bacterium. This isolated bacterium was observed to be Gram‐negative, aerobic growing, rod‐shaped and short chain. The results of bacterial fatty acid analysis and physiological characteristics were not matched to the database. The main fatty acids found in the bacterium were 65.96% branched chain saturated fatty acids (iso C11:0, anteiso C11:0 and iso C13:0~anteiso C19:0). The bacterium oxidized 35 carbon sources and weakly responded with 49 of the 95 different carbon sources analyzed with the Biolog identification system. Based on 16S rDNA sequence analysis, this bacterium was classified as a novel Bacillus species. 相似文献
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