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Taste sensitivity was evaluated by suprathreshold scaling of six concentrations each of sodium chloride, sucrose, citric acid, and quinine hydrochloride. Magnitude estimation was used as the method of scaling. The study group was composed of 22 males and 19 females were either patients (institutionalized) or staff members of the Jewish Institute for Geriatric Care. Data from each patient were used to compute individual slopes and Y-intercepts of the log to log transformations for each solution sequence. The mean age of the persons who were institutionalized was significantly higher than that of the staff members. In addition, the mean age of the females was 10 years older than that of the males. The older adult males seemed to have impaired taste function that resulted in significant decreases in total perceived intensity of several taste solutions. No significant differences were shown in taste ability between the relatively healthy younger staff member subjects and the older, more infirm, institutionalized subjects. 相似文献
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STOWELL L. I.; FAWCETT J. P.; BROOKE M.; ROBINSON G. M.; STANTON W. R. 《Alcohol and alcoholism (Oxford, Oxfordshire)》1997,32(4):507-516
Serum levels of carbohydrate-deficient transferrin (CDT) weremeasured in subjects of two independent studies using two differentcommercial kits. The kits measure CDT either as a percentageof total transferrin (AXIS %CDTTM, AXIS Biochemicals AS, Norway),or as the absolute amount (CDTectTM, Pharmacia, Sweden). Ina population of males (mean age 41 years) consisting of alcoholics,heavy, moderate and non-drinkers, a strong correlation was foundbetween AXIS %CDT and CDTect results (r=0.92, n=58, P<0.001).Sensitivity and specificity in detecting chronic alcoholic drinkingof over 60 g/day were 78 and 94% for the AXIS assay, and 83and 88% for the CDTect assay, respectively. In a populationfrom a birth cohort study, consisting of 21-year-old males andfemales with less excessive alcohol consumption, the correlationbetween AXIS %CDT and CDTect CDT was weaker but still statisticallysignificant (r=0.46. n=212, =<0.001). In this population,with specificities >83% in detecting alcohol consumptionlevels of 相似文献
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Data from a 1988 survey of US drinking habits and related problems revealed differences in male and female patterns of alcohol consumption. Men were more likely than women to be current drinkers (64 v. 41%), and beer accounted for a larger proportion of their overall intake. Men's average daily ethanol intake was about twice as high as that of women, 17.5 v. 8.9 g. Adjustment for differences in body weight and composition substantially reduced the male-to-female ratio of consumption. Men were more likely than women to be classified as heavy drinkers, and the excess proportion of males so categorized increased with the severity of the measure of heavy drinking. 相似文献
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Development of the neural crest involves a remarkable feat of coordinated cell migration in which cells detach from the neural tube, take varying routes of migration through the embryonic tissues and then differentiate at the end of their journey to participate in the formation of a number of organ systems. In general, neural crest cells appear to migrate without the guidance of long-range physical or chemical cues, but rather they respond to heterogeneity in the extracellular matrix that forms their migration substrate. Molecules such as fibronectin and laminin act as permissive substrate components, encouraging neural crest cell attachment and spreading, whereas chondroitin sulphate proteoglycans are nonpermissive for migration. A balance between permissive and nonpermissive substrate components seems to be necessary to ensure successful migration, as indicated by a number of studies in mouse mutant systems where nonpermissive molecules are over-expressed, leading to inhibition of neural crest migration. The neural crest expresses cell surface receptors that permit interaction with the extracellular matrix and may also modify the matrix by secretion of proteases. Thus the principles that govern the complex migration of neural crest cells are beginning to emerge. 相似文献
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REDMAN SALLY; WATKINS JULIA; EVANS LOUISE; LLOYD DEBORAH 《Health promotion international》1995,10(2):101-113
Breast feeding has nutritional, immunologic and antiallergicadvantages for the infant. Although it has been widely recommendedthat infants be exclusively breast fed until 46 monthsof age, only about half of all Australian babies currently receiveextended breast feeding. The present study evaluated an intensiveprogramme designed to increase the proportion ofprimi-parousmothers who breast fed for 4 months or longer. Women who registeredwith the hospital at least 20 weeks before delivery and whointended to breastfeed were eligible for the study. Two hundredand thirty-five women were allocated to receive either usualcare or an intensive breast feeding programme when they registeredwith the hospital. The intensive programme consisted of writtenmaterials, and group and individual sessions with a lactationcounsellor. It also included a visit from a breastfeeding consultantwhile in hospital after the birth and contact on return home.Women were followed up 6 weeks and 4 months after delivery.There were no significant differences in breastfeeding ratesbetween the control and intervention groups at either follow-uppoint. Breast feeding until 4 months was more likely among womenwhose baby did not receive a bottle feed while still in hospitaland who did not smoke, use the combined oral contraceptive pillor introduce solid food before 4 months. Those mothers who enjoyedand felt satisfied with breastfeeding were more likely to continueto 4 months. It seems likely that programmes designed to increasebreastfeeding will need to address underlying factors such ashospital policy rather than simply providing more health education. 相似文献
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The previously described cyclic delta opioid receptor-selective tetrapeptide H-Tyr-d -Cys-Phe-d -Pen-OH (JOM-13) was modified at residue 3 by incorporation of both natural and unnatural amino acids with varying steric, electronic, and lipophilic properties. Effects on mu and delta opioid receptor binding affinities were evaluated by testing the compounds for displacement of radiolabeled receptor-selective ligands in a guinea pig brain receptor binding assay. Results obtained with the bulky aromatic 1-Nal3 and 2-Nal3 substitutions suggest that the shape of the receptor subsite with which the side chain of the internal aromatic residue interacts differs for delta and mu receptors. This subsite of either receptor can accommodate the transverse steric bulk of the 1-Nal3 side chain but only the delta receptor can readily accept the more elongated 2-Nal3 side chain. Several analogs with pi-excessive heteroaromatic side chains in residue 3 were examined. In general, these analogs display diminished binding to mu and delta receptors, consistent with previous findings for analogs with residue 3 substitutions of modified electronic character. Several analogs with alkyl side chains in residue 3 were also examined. While delta receptor binding affinity is severely diminished with Val3, Ile3, and Leu3 substitutions, Cha3 substitution is very well tolerated, indicating that, contrary to the widely held belief, an aromatic side chain in this portion of the ligand is not required for delta receptor binding. Where possible, comparison of results in this delta-selective tetrapeptide series with those reported for analogous modification in the cyclic delta-selective pentapeptide [d -Pen2, d -Pen5]enkephalin (DPDPE) and linear pentapeptide enkephalins reveals similar trends. 相似文献
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Alcohol misuse prevention for young people: a systematic review reveals methodological concerns and lack of reliable evidence of effectiveness 总被引:2,自引:0,他引:2
In a systematic review we assessed the methodological quality of evaluations of alcohol misuse prevention programmes for young people, and recorded evidence of effectiveness. Studies were identified through systematic searches of electronic databases; hand searches of all obtained papers, existing reviews and several journals; and mailshots to key organizations, conferences and individuals. Relevant papers were checked and cross-checked by members of the review team, and only those studies with an experimental or quasi-experimental design and positive attributes on a number of other quality criteria were included in the review. After pre-screening over 500 papers which reported prevention programmes, information was systematically abstracted from 155 papers. Only 33 studies merited inclusion in the review, and most of these had some methodological shortcomings. Twenty-one studies reported some significant short- and medium-term reductions in drinking behaviour. Of two studies which carried out longer-term evaluations, only one reported a significant longer-term effect, with small effect sizes. No factors clearly distinguished partially effective from ineffective or harmful prevention programmes. In conclusion, the lack of reliable evidence means that no one type of prevention programme can be recommended. In particular there is a need to carry out well-designed scientific evaluations of the effectiveness of current or new prevention efforts which target young people's alcohol misuse. 相似文献