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61.
62.
Objective This study compared distributions of carotenoid intake and diet-serum correlations using two sources of carotenoid data: the US Department of Agriculture-National Cancer Institute (USDA-NCI) carotenoid food composition database and values accompanying the Block-NCI Health Habits and History Questionnaire (HHHQ).

Design and subjects A 100-item food frequency questionnaire was used to collect dietary data from 2,152 adults, aged 43 to 85 years, who were participating in the Nutritional Factors in Eye Disease Study, a population-based study designed to evaluate nutritional factors associated with age-related eye disease. Blood samples were collected from a random sample of 400 nonfasting participants in the study.

Results Median carotenoid intakes using HHHQ vs USDA-NCI data were alpha carotene (229 vs 223 μg/day), beta carotene (1,321 vs 1,325 μg/day), beta cryptoxanthin (72 vs 21 μg/day), lutein + zeaxanthin (653 vs 811 μg/day), and lycopene (593 vs 1,615 μg/day). All paired differences in carotenoid intake were significantly different from zero (Wilcoxon signed-rank, P<.0001). Despite these differences, the two databases similarly ranked individuals according to carotenoid intake: Spearman correlations ranged from .71 (lycopene) to .93 (alpha carotene). Differences between diet-serum correlations (adjusted for energy, body mass index, high density lipoprotein, and total cholesterol) using HHHQ vs USDA-NCI data were minor and not significant (P>.05): alpha carotene (r=.33 vs .32), beta carotene (r=.27 vs .32), beta cryptoxanthin (r=48 vs .53), lutein + zeaxanthin (r=.28 vs .24), and lycopene (r=.29 vs .25).

Conclusions Although estimates of carotenoid intake differed significantly, only minor differences in carotenoid rankings and diet-serum correlations were observed using either data source in this population. J Am Diet Assoc. 1996; 96:1271-1275.  相似文献   

63.
Culturally perceived illness and guinea worm disease surveillance   总被引:1,自引:0,他引:1  
Surveillance is a central component of the international guineaworm eradication effort to aid planning, monitoring and certificationof disease elimination. The programme is based on a standardcase definition of 'a person exhibiting or having a historyof a skin lesion with emergence of a guinea worm'. Local namesfor and cultural conceptions of the guinea worm illness experiencevary from this definition, either by being non-specific or inclusiveof other presentations, thus setting the stage for false positivecase reporting. False reports have serious implications on decisionsto allocate disease control resources, especially in the remoteregions where guinea worm is endemic. A recent case search inone district of southwestern Nigeria provided an opportunityto determine the prevalence of the various cultural manifestationsof guinea worm. Only 65% of total cases reported matched thestandard case definition. Furthermore, an additional 26% ofsmall farm villages would have been targeted for programme intervention,had interviewers not verified positive responses. Previous workhad shown that local health staff were not sensitive to theimportance of the case definition. Thus there is need, not onlyfor ethnographic study preceding design of surveillance activities,but also for the involvement of local health staff in this processto increase their commitment to and understanding of eradicationefforts  相似文献   
64.
Endocrine Modulation of Reproduction   总被引:4,自引:0,他引:4  
The ability of foreign compounds to affect the functioning ofvarious endocrine systems is currently thought responsible fora wide variety of effects. The presentations in this Symposiumreviewed the evidence for and against the involvement of endocrinesystems in several different aspects of reproduction. The mechanismbehind the ability of a triazine herbicide to cause enhancedappearance of mammary tumors in one strain of female rats isreviewed by Stevens. The data suggest that enhanced aging, notdirect mammary modulation, is responsible. Dietary phytoestrogens,the mediators of their actions, their effects in various biologicalsystems, and the relationships between phytoestrogen producersand consumers are all provocatively and succinctly reviewedby Hughes. Kelce presents the strategy used to dissect the modeand mechanisms of action of a fungicide that opened a new awarenessin reproductive toxicology: the possibility of xenobiotics beingantiandrogens. Finally, to heighten our understanding of theinterplay among hormonal systems in vivo, Hess reviews the datathat show that androgens are not the only hormones importantin the development of the male reproductive system: the pituitaryis shown to play a critical role at specific stages of development.The breadth of these presentations, and the implications oftheir findings, should make us pause and realize how much thereis still to discover about the interaction between the reproductivesystem and anthropogenic compounds.  相似文献   
65.
An Analysis of Nasal Irritation Thresholds Using a New Solvation Equation   总被引:2,自引:1,他引:2  
In the present paper we have developed a quantitative structure-activityrelationship (QSAR) equation for nasal pungency caused by nonreactivevolatile organic compounds (VOCs). Our QSAR was developed uponpreviously published nasal pungency thresholds in anosmics,i.e., patients lacking a sense of smell and thus respondingonly to sensory irritation evoked by trigeminal nerve stimulation.The reported solvation equation, which fits the data with considerableprecision, describes sensory potency in terms of interactionvia electron pairs, dipolarity/polarizability, hydrogen bondacidity and basicity, and hydrophobicity. It correspondinglysuggests relevant physicochemical properties of the biophasewhere the sensory response is brought about. The equation impliesthat in the range of molecular size where nonreactive VOCs canproduce any pungency, transport from the air to the biophasestrictly determines potency. In this respect, the potency ofnasal pungency shares characteristics with the ability of VOCsto cause narcosis and anesthesia.  相似文献   
66.
Forms of 2,4-dichlorophenoxyacetic acid (collectively knownas 2,4-D) are herbicides used to control a wide variety of broadleafand woody plants. Doses in the 2-year chronic/oncogenicity ratstudy were 0, 5, 75, and 150 mg/kg/day. The chronic toxicityparalleled subchronic findings, and a NOEL of 5 mg/kg/day wasestablished. A slight increase in astrocytomas observed (inmales only) at 45 mg/kg/day in a previously conducted chronicrat study was not confirmed in the present study at the highdose of 150 mg/kg/day. Doses in the 2-year mouse oncogenicitystudies were 0, 5, 150, and 300 mg/kg/day for females and 0,5, 62.5, and 125 mg/kg/day for males. No oncogenic effect wasnoted in the study. In summary, the findings of these studiesindicate low chronic toxicity of 2,4-D and the lack of oncogenicresponse to 2,4-D following chronic dietary exposure of 2,4-Din the rat and mouse.  相似文献   
67.
Detection of Aldehydes in Bronchoalveolar Lavage of Rats Exposed to Ozone   总被引:2,自引:0,他引:2  
We report the detection of hexanal, heptanal, and nonanal inthe bronchoalveolar lavage (BAL) of rats exposed to 0.5 to 10ppm ozone with or without simultaneous 5% CO2. These three aldehydesprimarily result from the Criegee ozonation of specific mono-or polyunsaturated fatty acids that are present in significantamounts in the rat lung; e.g., palmitoleic acid gives heptanal,oleic gives nonanal, and linoleic and arachidonic can give hexanal.Hexanal also is produced in the ozone-initiated autoxidationof any n-6 polyunsaturated fatty acid, and thus is a measureof generalized oxidative stress. (Monounsaturated fatty acidsdo not undergo appreciable autoxidation.) This detection andquantitation of aldehydes directly demonstrates for the firsttime that unsaturated fatty acids undergo Criegee ozonationin the lung when ozone is inhaled. Exposure to ozone alone producedsmaller apparent yields of the three aldehydes than did exposureto ozone plus 5% CO2. Hexanal, heptanal, and nonanal can bedetected in BAL of rats 5 hr after the end of the ozone exposure,but after more than 5 hr only hexanal can be found, probablyfrom ozone-induced autoxidation of n-6 PUFA that continues afterozone exposure. The measured amounts of aldehydes are low, andthat, coupled with inherent biovariability, suggests that aldehydesmay not be useful as quantitative dosimeters. However, theycan be useful biomarkers, since some of these aldehydes (e.g.,nonanal) are produced in ozone-specific pathways and aldehydesare the most easily detected among the lipid ozonation products(LOP). Furthermore, our identification of these aldehydes byBAL, coupled with our recognition that ozone itself cannot penetratefar enough into the lung to cause many of the effects associatedwith the inhalation of ozone, suggests that these aldehydes,as well as other types of LOP (such as hydroxyhydroperoxidesand Criegee ozonides), may act as signal transduction molecules,activating lipases and causing the release of inflammatory moleculesby a variety of pathways not yet entirely elucidated.  相似文献   
68.
BACKGROUND Expanded polytetrafluoroethylene implants have been used successfully for augmentation of thinning lips, deep nasolabial folds, and marionette lines without the risk, recovery time, and expense of major surgery.
OBJECTIVE The objective was to assess long-term results and patient satisfaction with expanded polytetrafluoroethylene implants.
MATERIALS AND METHODS A retrospective chart review was performed on all patients treated with expanded polytetrafluoroethylene implants from January 1, 2001, to July 1, 2002.
RESULTS Eighty-five implants were placed in 33 patients. Forty-six percent of implants were placed in the nasolabial folds, 34% in the lips, 16.5% in the marionette lines, 2% in the oral commisures, and 1% in the glabella. Eighty-seven percent of implants remain in place with excellent correction. Eleven implants in 6 patients were removed. Four of the 11 implants removed were considered too small by the patient and were replaced with larger implants without difficulty. The other reasons for implant removal included malposition, localized swelling, and an unnatural feel. Patient and physician satisfaction with the treatment was high.
CONCLUSION Expanded polytetrafluoroethylene implants are a safe, effective, and permanent option for facial volume augmentation. Patients who have had their implants in place for 5 years or more continue to report high satisfaction with the treatment.  相似文献   
69.
TARO KONO  MD  PHD    BRIAN M. KINNEY  SM  MD    WILLIAM FREDERICK GROFF  DO    HENRY H. CHAN  MD  FRCP    ALI RIZA ERCOCEN  MD    MOTOHIRO NOZAKI  MD  PHD 《Dermatologic surgery》2008,34(S1):S25-S30
BACKGROUND At present, various hyaluronic acids are being used to rejuvenate facial skin. There is no comparative study of single cross-linked hyaluronic acid (SCHA) versus double cross-linked hyaluronic acid (DCHA). The objective of our study is to compare the effectiveness and complications of SCHA versus DCHA in the treatment of glabellar lines.
METHODS Ten female patients were enrolled in this randomized, evaluator-blind study. One side (left vs. right) of each patient's glabellar lines was treated with SCHA and the other side was treated with DCHA. Two independent blinded observers reviewed the clinical photographs at 3, 6, 9, and 12 months after the treatment and assessed for degree of improvement as well as complications.
RESULTS The two products were equally effective in producing an optimal cosmetic result, although at 6, 9, and 12 months posttreatment, a higher proportion of patients showed over 50% improvement with DCHA than with SCHA. At 12 months posttreatment, DCHA was considered superior in 70% of patients, whereas SCHA was superior in 10% of patients.
CONCLUSIONS Both SCHA and DCHA are equally effective in producing an optimal cosmetic result. DCHA provides a more durable esthetic improvement when compared to SCHA in the treatment of glabellar lines.  相似文献   
70.
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