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991.
Human mononuclear cell modulation of endothelial cell proliferation   总被引:4,自引:0,他引:4  
Endothelial cell proliferation is a histologic characteristic of several forms of nephritis characterized by infiltration of the glomerulus with mononuclear cells. To investigate the mechanism mediating this event, human endothelial cells isolated from umbilical veins and cultured in vitro were incubated with supernatants of cultured human mononuclear cells. Supernatants from mononuclear cells exerted a dose-dependent stimulatory effect on endothelial cell proliferation. The stimulatory effect of supernatant was almost entirely removed by prior depletion of mononuclear cells of monocytes by adherence, suggesting that a monocyte product was responsible for the activity. To investigate the nature of the ligand responsible, partially purified human interleukin I added to endothelial cell cultures was found to stimulate cellular proliferation.  相似文献   
992.
The asymmetric phase-transfer catalytic alkylation of peptides has been achieved by the use of designed C(2)-symmetric chiral quaternary ammonium bromide 1 as catalyst. Excellent stereoselectivities were uniformly observed in the alkylation with a variety of alkyl halides and the efficiency of the transmission of stereochemical information was not affected by the side-chain structure of the preexisting amino acid residues. This method also enables an asymmetric construction of noncoded alpha,alpha-dialkyl-alpha-amino acid residues at the peptide terminal. Since this chirality can be efficiently transferred to the adjacent amino acid moiety, our approach provides a general procedure not only for the highly stereoselective terminal functionalization of peptides but also for the sequential asymmetric construction of unnatural oligopeptides, which should play a vital role in the peptide-based drug discovery process.  相似文献   
993.
Vitamin A, cigarette smoking, and airway obstruction   总被引:3,自引:0,他引:3  
The hypothesis that vitamin A, or foods rich in vitamin A such as milk, protects against the development of airway obstruction was tested in a subsample of data from the 1971-1975 National Health and Nutrition Examination Survey. The relative risk (estimated by relative odds) of having airway obstruction, defined as a FEV1/FVC less than or equal to 65%, was measured for different levels of nutrient and food group intakes after adjustment for age, sex, Quetelet Index, caloric intake, and cigarette smoking. Among the white respondents (never smokers or current smokers) whose recalled diet could be considered as typical of their usual diet, the relative odds of having airway obstruction was inversely related to vitamin A intake (x2 for trend = 7.2, p less than 0.01). In the analysis by food groups, the adjusted relative odds of airway obstruction for meat and poultry were 2.4 (95% confidence limits: 1.0 to 5.8) and for milk 1.6 (95% confidence limits: 1.0 to 2.5). The association of airway obstruction with lack of vitamin A or milk intake was clearer among smokers. These findings suggest that a diet poor in vitamin A increases the risk of airway obstruction, and are consistent with the previously reported association of chronic bronchitis, milk intake, and smoking.  相似文献   
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Objectives

The aim of this article is to present an overview of omega-3 fatty acids, their anti-inflammatory properties and potential use as an adjunct for periodontal therapy.

Materials and methods

A general literature search was conducted to provide an overview of omega-3 fatty acids, their metabolism and anti-inflammatory properties. A more specific literature search of PubMed and EMBASE was conducted to identify articles dealing studies investigating the effects of omega-3 fatty acids in the treatment of periodontitis in animals and humans and included cross-sectional, longitudinal and intervention designs.

Results

To date, there is good emerging evidence that dietary supplementation with fish oil may be of some benefit and this is enhanced if combined with aspirin. All clinical intervention studies to date have been on small sample sizes, and this indicates there is need for larger and more robust clinical trials to verify these initial findings.

Conclusions

Dietary supplementation with fish oil could be a cost-effective adjunctive therapy to the management of periodontal disease.

Clinical relevance

The host modulatory properties of omega-3 fatty acids warrant further assessment of their use as an adjunct in the management of periodontitis.
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