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排序方式: 共有596条查询结果,搜索用时 15 毫秒
1.
2.
Peter R. Ellis Victoria J. Burley Anthony R. Leeds David B. Peterson† 《Journal of human nutrition and dietetics》1988,1(2):77-84
We have developed a guar wholemeal bread and tested its physiological efficacy and sensory qualities. The objective of the study was to estimate the optimum concentration of guar in bread required to reduce postprandial glycaemia and insulinaemia without adversely affecting the quality of the bread. Following overnight fasts, 15 normal weight, non-diabetic subjects consumed meals of wholemeal bread alone (controls) and supplemented with guar at three different concentrations (5, 10 and 15% replacement of wheat flour). Blood samples for glucose and insulin analysis were taken preprandially, and at 30 and 60 min after the start of each meal. The acceptability of the wholemeal control and guar breads was assessed using a hedonic scaling method. A significantly lower blood glucose rise at 30 min was found after the 15% guar bread meal compared to the control. Plasma insulin responses at 30 and 60 min were significantly lower after the 10 and 15% guar bread meals compared to the controls. Hedonic scores indicated that the subjects found the 5 and 10% guar breads acceptable and in the case of the 5% variety the mean score was identical to the control. We suggest that a guar concentration of between 5 and 10% replacement of wheat flour (wholemeal or white) should be used for the baking of guar wholemeal bread but further work is needed to define the precise quantity of guar required. 相似文献
3.
Synthesis and structure-activity relationships of new 9-N-alkyl derivatives of 9(S)-erythromycylamine 总被引:4,自引:0,他引:4
H A Kirst J A Wind J P Leeds K E Willard M Debono R Bonjouklian J M Greene K A Sullivan J W Paschal J B Deeter 《Journal of medicinal chemistry》1990,33(11):3086-3094
A series of new 9-N-alkyl derivatives of 9(S)-erythromycylamine has been synthesized by reductive alkylation of erythromycylamine with aliphatic aldehydes and sodium cyanoborohydride. Alternative syntheses employing hydrogenation methods have also been developed. These new 9-N-alkyl derivatives possess excellent antimicrobial activity in vitro and in vivo, especially when administered orally to treat experimental infections in mice. From structure-activity studies, 9-N-(1-propyl)erythromycylamine (LY281389) was selected as the most efficacious derivative. These methods have also been extended to the synthesis of some 9-N,N-dialkyl derivatives of erythromycylamine. 相似文献
4.
Structure-activity studies of 20-deoxo-20-amino derivatives of tylosin-related macrolides 总被引:1,自引:0,他引:1
H A Kirst K E Willard M Debono J E Toth B A Truedell J P Leeds J L Ott A M Felty-Duckworth F T Counter E E Ose 《The Journal of antibiotics》1989,42(11):1673-1683
Reductive amination of the C-20 aldehyde group of tylosin and related macrolides yielded a large series of derivatives with potentially useful antibiotic properties. Evaluation of these new compounds was conducted on the basis of: 1) Broad antimicrobial spectrum in vitro, with particular emphasis on inhibition of Pasteurella multocida and Pasteurella haemolytica; 2) in vivo efficacy, especially when given orally, against P. multocida in experimental infections in chicks; and 3) bioavailability after oral administration to laboratory animals. The most useful activity was found within a series of derivatives produced by reductive amination of desmycosin with secondary amines. 相似文献
5.
Different modulation by histamine of IL-4 and interferon-gamma (IFN-γ) release according to the phenotype of human Th0, Th1 and Th2 clones
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Histamine, an important inflammatory mediator in allergic diseases and asthma, has been reported to have modulator effects on T cells, suggesting that the bronchial microenvironment may regulate the function of resident T cells. We examined the effect of histamine on the release of the Th2-associated cytokines IL-4 and IL-5 and the Th1-associated cytokine IFN-γ by 30 CD4+ T cell clones from peripheral blood or bronchial biopsy of one atopic subject. Based on the IL-4/IFN-γ ratio, the clones were ascribed to the Th2 (ratio >1), Th0 (ratio 0.1 and 1) or Th1 (ratio <0.1) phenotype. Histamine inhibited IFN-γ production by Th1-like cells (P<0.02, Kruskall–Wallis), especially from bronchial biopsy, but had no effect on IL-4 release. Regarding Th0 clones, histamine inhibited IL-4 production (P<0.02) in a dose-dependent manner and slightly inhibited IFN-γ production, but had no effect on Th2-like cells. Histamine had a heterogeneous and insignificant effect on IL-5 production. The H2-receptor antagonist ranitidine completely reversed the inhibition of IL-4 and IFN-γ production, whereas the agonist dimaprit mimicked this effect. In contrast, H1- and H3-receptor agonists and antagonists had no significant effect. These data demonstrate that histamine has different effects on IL-4 and IFN-γ release by T helper cells according to their phenotype via H2-receptors. This study extends the immunomodulatory effects of histamine which may contribute to the perpetuation of airway inflammation in asthma. 相似文献
6.
The role of size, sequence and haplotype in the stability of FRAXA and FRAXE alleles during transmission 总被引:2,自引:5,他引:2
Murray A; Macpherson JN; Pound MC; Sharrock A; Youings SA; Dennis NR; McKechnie N; Linehan P; Morton NE; Jacobs PA 《Human molecular genetics》1997,6(2):173-184
Factors involved in the stability of trinucleotide repeats during
transmission were studied in 139 families in which a full mutation,
premutation or intermediate allele at either FRAXA or FRAXE was
segregating. The transmission of alleles at FRAXA, FRAXE and four
microsatellite loci were recorded for all individuals. Instability within
the minimal and common ranges (0-40 repeats for FRAXA, 0-30 repeats for
FRAXE) was extremely rare; only one example was observed, an increased in
size at FRAXA from 29 to 39 repeats. Four FRAXA and three FRAXE alleles in
the intermediate range (41-60) repeats for FRAXA, 31-60 for FRAXE) were
unstably transmitted. Instability was more frequent for FRAXA intermediate
alleles that had a tract of pure CGG greater than 37 although instability
only occurred in two of 13 such transmissions: the changes observed were
limited to only one or two repeats. Premutation FRAXA alleles over 100
repeats expanded to a full mutation during female transmission in 100% of
cases, in agreement with other published series. There was no clear
correlation between haplotype and probability of expansion of FRAXA
premutations. Instability at FRAXA or FRAXE was more often observed in
conjunction with a second instability at an independent locus suggesting
genomic instability as a possible mechanism by which at least some FRAXA
and FRAXE mutations arise.
相似文献
7.
Acromegaly is a disease with protean manifestations that are well described in the literature. One finding infrequently encountered is aneurysmal dilatation of the internal carotid arteries and their branches. A case is presented, with CT documentation, in which the enlarged cavernous portions of the internal carotid arteries prolapsed into the sella turcica and enlarged it. Frontal bossing, frontal sinus enlargement, a dense cortical calvarium, prominent inion, and proptosis secondary to extraocular muscular enlargement were findings also present in this patient. The sella CT appearance has brought the term "kissing intrasellar arteries" to mind to suggest the diagnosis. 相似文献
8.
9.
Lymphangiograms were made in dogs with experimental congestive heart failure by cannulation of the left cardiac efferent (LCE), left pulmonary efferent (LPE), or cardiopulmonary lymphatic and injection of radiopaque medium. The lymphoangiograms showed cardiac enlargement and dilated mediastinal lymphatic channels consistent with an increase in lymph flow. By consecutive injections in the LCE and LPE, wer demonstrated that a common channel, the cardiopulmonary lymphatic, is opacified by injection in either the LPE or LCE. This common channel has been called the "cardiac lymphatic" and used for the collection of "cardiac" lymph. The authors' experiments suggest that this cardiopulmonary lymphatic carries both cardiac and pulmonary lymph. 相似文献
10.
Falx and interhemispheric fissure on axial CT: II. Recognition and differentiation of interhemispheric subarachnoid and subdural hemorrhage 总被引:1,自引:0,他引:1
R D Zimmerman E J Russell E Yurberg N E Leeds 《AJNR. American journal of neuroradiology》1982,3(6):635-642
Interhemispheric hyperdensity or unenhanced computed tomography was originally considered a sign of subarachnoid hemorrhage, the "falx sign." It has since been identified as a normal feature and has also been seen with interhemispheric subdural hemorrhage. To determine the differential features of interhemispheric hemorrhage, 50 patients with subarachnoid hemorrhage and 32 patients with interhemispheric subdural hematomas were reviewed. Subarachnoid hemorrhage produced anterior interhemispheric hyperdensity only, with a zigzag contour and extension from the calvarium to the rostrum of the corpus callosum. Interhemispheric subdural hematomas produce unilateral crescentic hyperdensities that are largest in the posterior superior part of the fissure, behind and above the splenium of the corpus callosum. Interhemispheric hyperdensity in children is more complex. Because the anterior part of the fissure is narrow in younger patients, subarachnoid hemorrhage may go undetected. Likewise, interhemispheric subdural hematomas in children are smaller and more difficult to recognize. They produce asymmetric thickening of the falx shadow with extension over the tentorium. They are, however, of great significance since they are generally seen in abused patients and carry a poor prognosis. 相似文献