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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
3.
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
4.
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
5.
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
6.
7.
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
8.
We have constructed a series of retroviral vectors in which the expression of antisense RNA targeted at the full length coding sequence of HIV-1 tat or rev was driven by three different promoters and in the context of double-copy or single-copy vectors. Jurkat cells transduced by these vectors were shown to express the expected tat or rev antisense RNA without alteration in cell proliferation or surface CD4 expression. After challenge with HIV, four patterns of protection were identified, with the degree of protection being determined primarily by the design of the expression system. In those patterns showing long-term complete protection, we could detect no HIV p24 in the culture supernatants or in the cells, and no HIV RNA or HIV proviral DNA (by PCR), during a 23-week follow-up. Experiments designed to rescue any live virus still formed in the culture after 20 weeks’ challenge demonstrated that, with some constructs, infectious virus could no longer be isolated, while with other constructs, only a low level of infectious virus was still being formed and providing a continuing virus challenge, although all other markers of infection remained undetectable. Our results demonstrated that antisense RNA expression driven by tRNA promoter in the context of a double-copy vector conferred better long-term protection against HIV infection compared to that driven by HIV LTR or MLV LTR promoters, and that the optimized vectors may be useful in developing a gene therapy against HIV-1 infection and AIDS. 相似文献
9.
PETERSEN DEBORAH WISSINK; POWERS JOHN F.; AARDEMA MARILYN J.; LEBOEUF ROBERT A.; SMITH LAURENCE A. 《Toxicological sciences》1989,13(1):137-145
The estimated single-dose oral toxicity (50% lethality) of succinatetartrates (ST) was 23 g/kg in rats. ST produced minimalto moderate dermal irritation but no evidence of systemic toxicityin a standard acute percutaneous toxicity test in rabbits. STwas not an eye irritant in a standard rabbit low-volume eyeirritation test ST was not genotoxic in a series of six genotoxicitytests. A 14-day oral gavage study in rats at a dose range of0.051.0 g ST/kg/day produced only gastric irritation.The no-observed-effect level (NOEL) for gastric irritation was0.1 g/kg for males and 0.05 g/kg for females. A 28-day percutaneoustoxicity study in rabbits produced minimal to moderate dermalirritation and no adverse systemic effects at a high dose of450 mg ST/kg/day. Single-dose absorption, distribution, andelimination (ADE) studies in male rats showed that 1015%of an oral dose and 13% of a dermal dose were absorbed.Approximately 98% of the orally administered ST was eliminatedas 14C in urine, feces, or expired CO2 after 72 hr. Approximately80% of the dermally absorbed 14C dose was eliminated in urine,feces, or expired CO2 after 72 hr. In conclusion, no adverseeffects were noted in acute toxicity, genotoxicity, or subchronictoxicity studies conducted with ST. 相似文献
10.
DEBORAH J. ANDERSON JOSEPH A. HILL 《American journal of reproductive immunology (New York, N.Y. : 1989)》1988,17(1):22-30
ABSTRACT: A role of cell-mediated immunity in immunologic infertility is indicated by a number of animal immunization studies and by reported clinical associations between cellular immune responses and infertility. Furthermore, recent technical advances in the field of cellular immunology have enabled advanced studies on the cellular and soluble mediators of cell-mediated immune responses and their interactions with reproductive processes. In this article we review some of the recent technical and conceptual advances in cellular immunology, the classic literature on cellular immune responses in infertility, and recent evidence that certain products of activated lymphocytes and macrophages significantly affect reproductive functions. 相似文献