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排序方式: 共有485条查询结果,搜索用时 15 毫秒
1.
Zengjuan Zheng Weifen Zhang Weiqing Sun Xiaojian Li Jinghua Duan Juanjuan Cui Zhanqin Feng Heidi M. Mansour 《Journal of materials science. Materials in medicine》2013,24(11):2549-2559
The aim of this paper was to investigate the effect of carboxymethyl chitosan anti-adhesion solution on prevention of postsurgical adhesion. Forty adult male Wistar rats were randomly divided into three groups: 0.9 % normal saline solution (group A), hyaluronic acid gels (group B) and carboxymethyl chitosan anti-adhesion solution (group C). The animals were treated with normal saline, hyaluronic acid gels or carboxymethyl chitosan anti-adhesion solution at the time of surgery. After 2 or 3 weeks, the degree of adhesions and histological effects were determined. The adhesions in groups B and C were significantly decreased, and the levels of TGF-β1 and hydroxyproline in group C were significantly lower than that in group A (P < 0.05). The histopathology in group C showed fewer inflammatory cells and fibroblasts. Carboxymethyl chitosan anti-adhesion solution can effectively prevent postoperative adhesion which is a promising drug delivery system in the context of postsurgical anti-adhesion. 相似文献
2.
The impact of gamma-irradiation on 5′-nucleotides and on the free amino acids tyrosine and phenylalanine in fresh mushrooms was studied. After irradiation the samples were freeze-dried to avoid enzyme induced chemical changes. Three 5′-nucleotides could be detected using HPLC–UV and LC–ESI-MS: adenosine 5′-monophosphate (AMP), guanosine 5′-monophosphate (GMP) and guanosine 5′-diphosphate (GDP). Irradiation significantly reduced (p = 0.05) the GDP concentration (22%). AMP showed a marked reduction (46%) only at 5 kGy. GMP, tyrosine, and phenylalanine were not affected by gamma-irradiation. 相似文献
3.
4.
Heidi R Grimmer Veena Parbhoo Robert M McGrath 《Journal of the science of food and agriculture》1992,59(2):251-256
Polyphenols extracted from a bird-resistant sorghum (Sorghum bicolor (L) Moench) grain cultivar SSK30 were separated into three crude fractions: non-tannin polyphenols with small Mr (F1); proanthocyanidins with Mr values between 2000 and 10000 (F2); and proanthocyanidins with much larger Mr values of around 10000-50000 (F3). Each fraction was tested for mutagenicity using mutants of Salmonella typhimurium (the Ames test) or the somatic mutation and recombination test (SMART) employing Drosophilu melanogaster. None of the fractions was positive with either test. On the other hand the crude polyphenols all acted as antimutagens when coincubated with mutants of S typhimurium and standard mutagens (sodium azide, daunomycin and 2-aminofluorene). The order of antimutagenicity was F3> F2> F1, a decrease with decreasing Mr. It is possible that a different mechanism of polyphenol antimutagenicity occurs against the mutagen sodium azide when compared with the mutagens daunomycin and 2-aminofluorene. 相似文献
5.
Muniyandi Kasipandi Jagadeesan Gayathri George Blassan P. Manoharan Ashwini Lydia Nataraj Gayathri Abrahamse Heidi Thangaraj Parimelazhagan 《Food science and biotechnology》2022,31(13):1717-1728
Food Science and Biotechnology - A rich source of nutrients, figs have a number of clinically validated benefits. This study aimed to evaluate the in vitro simulated gastrointestinal digestion, and... 相似文献
6.
Mari J. Jaakamo Tytti J. Luukkonen Piia K. Kairenius Ali R. Bayat Seppo A. Ahvenjärvi Tuomo M. Tupasela Johanna H. Vilkki Kevin J. Shingfield Heidi M. Leskinen 《Journal of dairy science》2019,102(10):8825-8838
We examined the effects of 2 grass silage-based diets differing in forage:concentrate (FC) ratio and those of a red clover silage-based diet on intake, milk production, ruminal fatty acid (FA) biohydrogenation, milk FA composition, and milk fat globule (MFG) size distribution. Ten multiparous Nordic Red cows received the following treatments: grass silage-based diets containing high (70:30, HG) or low (30:70, LG) FC ratio or a red clover silage-based diet with an FC ratio of 50:50 (RC) on a dry matter basis. Determinations of MFG were performed from fresh milk samples without addition of EDTA so the results of fat globules >1 µm in diameter are emphasized instead of the entire globule population. Lower FC ratio in grass silage-based diets increased milk production with no effect on daily fat yield, leading to 13% lower milk fat concentration. The effect of FC ratio on MFG size was moderate. It did not affect the volume-weighted diameter in grass silage-based diets, although LG lowered the volume-surface diameter of MFG in the size class >1 µm compared with HG. Compared with HG, feeding LG moderately decreased the biohydrogenation of 18:2n-6, leading to a higher level of polyunsaturated fatty acids in milk fat. Feeding RC lowered milk fat concentration and daily milk fat yield compared with grass silage-based diets. The volume-weighted diameter of MFG in the size class >1 µm was smaller in RC milk compared with grass silage-based diets. Feeding RC increased the flow of 18:3n-3 at the omasum by 2.4-fold and decreased the apparent ruminal 18:3n-3 biohydrogenation compared with grass silage-based diets despite similar intake of 18:3n-3. It also resulted in the lowest amount of saturated FA and the highest amounts of cis-9 18:1, 18:3n-3, and polyunsaturated FA in milk. In conclusion, LG decreased milk fat content and induced minor changes in MFG size distribution compared with HG, whereas RC lowered milk fat production, altered milk FA composition to nutritionally more beneficial direction, and led to smaller MFG compared with grass silage-based diets. 相似文献
7.
Mirjam Frischknecht Theodorus H.E. Meuwissen Beat Bapst Franz R. Seefried Christine Flury Dorian Garrick Heidi Signer-Hasler Christian Stricker Anna Bieber Ruedi Fries Ingolf Russ Johann Sölkner Alessandro Bagnato Birgit Gredler-Grandl 《Journal of dairy science》2018,101(2):1292-1296
The accuracy of genomic prediction determines response to selection. It has been hypothesized that accuracy of genomic breeding values can be increased by a higher density of variants. We used imputed whole-genome sequence data and various single nucleotide polymorphism (SNP) selection criteria to estimate genomic breeding values in Brown Swiss cattle. The extreme scenarios were 50K SNP chip data and whole-genome sequence data with intermediate scenarios using linkage disequilibrium-pruned whole-genome sequence variants, only variants predicted to be missense, or the top 50K variants from genome-wide association studies. We estimated genomic breeding values for 3 traits (somatic cell score, nonreturn rate in heifers, and stature) and found differences in accuracy levels between traits. However, among different SNP sets, accuracy was very similar. In our analyses, sequence data led to a marginal increase in accuracy for 1 trait and was lower than 50K for the other traits. We concluded that the inclusion of imputed whole-genome sequence data does not lead to increased accuracy of genomic prediction with the methods. 相似文献
8.
Swanson HK Johnston TA Schindler DW Bodaly RA Whittle DM 《Environmental science & technology》2006,40(5):1439-1446
We compared total mercury concentrations ([Hg]) among 6 forage fish species in 25 central Canadian lakes and related [Hg] to adjusted-delta15N (an index of trophic position), delta13C, growth rate, and a suite of environmental variables. Growth rates were also compared among species and related to environmental variables. We found that rainbow smelt (Osmerus mordax), a recent invader in many of these lakes, had intermediate [Hg] and growth rates relative to other species. Forage fish growth rates differed significantly among species and were related to latitude (inverse relationship) and lake conductivity (positive relationship). Mercury concentrations also differed significantly among species and the strongest predictors were growth rate and lake conductivity; [Hg] was significantly and negatively related to both. Adjusted-delta15N explained very little variation in [Hg] and was significant only when the analysis was restricted to biotic variables. These results indicate that biomagnification may not be observed at fine scales of trophic differentiation and that rainbow smelt are unlikely to cause post-invasion [Hg] increases in most predatory fish species. 相似文献
9.
Peters J Mac K Wichmann-Schauer H Klein G Ellerbroek L 《International journal of food microbiology》2003,88(2-3):311-314
Presently, enterococci take the third place of bacterial pathogens associated with nosocomial infections, after staphylococci and Escherichia coli. Especially, the resistances of enterococci to several available antibiotics are threatening. We attempted to determine which species of enterococci could be found in food of animal origin and their significance according to their antibiotic resistances for human beings. From November 2000 to May 2002 we investigated 155 samples of food of animal origin bought in retail outlets in Germany: 27 samples of sausages, 19 of ham, 83 of minced meat, 26 of cheese. From these food samples we isolated 416 enterococcal strains. The most frequent species was Enterococcus faecalis (299 strains); furthermore, we found Enterococcus faecium (54 strains), Enterococcus durans together with Enterococcus hirae (24 strains), Enterococcus casseliflavus (22 strains), Enterococcus avium (9 strains) and Enterococcus gallinarum (8 strains). We focused on the resistance patterns of 118 selected E. faecium and E. faecalis strains to 13 antimicrobial active agents (ampicillin, amoxicillin/clavulanic acid, avilamycin, chloramphenicol, enrofloxacin, erythromycin, flavomycin, gentamicin, penicillin, quinupristin/dalfopristin, teicoplanin, tetracycline and vancomycin). From the clinical point of view, the situation of antibiotic resistance to the examined antimicrobial agents seemed to be favourable. The investigated strains were sensitive to ampicillin and amoxicillin/clavulanic acid. These antibiotics are, in combination with an aminoglycoside, for example gentamicin, agents of choice for the treatment of enterococcal infections in human medicine. Only one E. faecium strain was resistant to penicillin, while all strains were sensitive to the glycopeptide antibiotics, vancomycin and teicoplanin. Resistances found against the antibiotics, tetracycline, quinupristin/dalfopristin and erythromycin, are causes for concern. 相似文献
10.