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1.
The absorption of iron from soya-bean (Glycine hispida)-based and milk-based infant formulas was assessed in 138 multiparous Indian women, using the erythrocyte utilization of radioactive Fe method. Fe absorption was significantly greater from the basal milk formula (1.5 g protein) than it was from the basal soya-bean formula (2.3 g protein), with geometric mean values of 0.083 and 0.044 respectively. Ascorbic acid markedly increased Fe absorption from the milk-based formula in a dose-dependent fashion. The increase was fivefold when the ascorbic acid:Fe ratio on a weight-for-weight basis was 6:1 and over tenfold when it was 20:1. In contrast, ascorbic acid had a less-marked effect on the absorption of Fe from the soya-bean-based formula, with only a two- to threefold increase at an ascorbic acid:Fe ratio of 20:1. The geometric mean Fe absorption from the soya-bean formula (1.27 mg Fe, 2.3 g isolated soya-bean protein (ISP] was somewhat less than that from the same amounts of ISP and ascorbic acid made up in milk (0.075 and 0.113 respectively). However, a direct comparison between the soya-bean formula in milk and in water showed no significant difference (0.043 and 0.060 respectively). Fe absorption from a drink containing 10 g ISP and 30 mg ascorbic acid was significantly better than that from a similar drink containing the soya-bean flour from which ISP is extracted (0.044 and 0.027 respectively). Heating ISP to 200 degrees for 2 h before its use had no effect on Fe availability.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Recurrent aphthous ulcers in patients with HIV infection can cause significant morbidity, which makes successful diagnosis and treatment imperative. We have found that the diagnostic paradigm for recurrent aphthous ulcers in HIV-seronegative patients, which is based on the ulcers' clinical appearance, location, absence of other ulcer-causing pathogens or pathogenic processes, and response to therapy, may be successfully applied to recurrent aphthous ulcers in HIV-infected patients. However, one must be alert for ulcers with uncommon causes as well as ulcers with common causes that have atypical clinical appearances that may mimic recurrent aphthous ulcers. The topical glucocorticoids, which are used to treat recurrent aphthous ulcers in HIV-seronegative patients, proved very effective in HIV-infected patients for treatment of herpetiform and minor ulcers and most major ulcers and were without notable side effects. A few severe cases of major recurrent aphthous ulcers required treatment with systemic prednisone, and some side effects were encountered.  相似文献   
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Triadimefon is a triazole fungicide that produces hyperactivity in both mice and rats similar to that seen following administration of compounds with catecholaminergic activity (e.g., d-amphetamine). To determine whether the triadimefon-induced hyperactivity is due to an action on CNS catecholaminergic systems, we evaluated the effects of combined treatment of triadimefon with either the tyrosine hydroxlase inhibitor d,l--methyl-p-tyrosine methyl ester HCl (MPT) or the amine depletor reserpine. Adult male Long-Evans hooded rats, approximately 70 days of age were used. Dosage-effect functions were determined for MPT (0–200 mg/kg IP), reserpine (0–2.5 mg/kg IP), d-amphetamine (0–3 mg/kg IP), and methylphenidate (0–40 mg/kg IP). Motor activity was measured as photocell interruptions in figure-eight mazes. The interaction between triadimefon and MPT was determined with the following groups: 1) vehicle control; 2) 200 mg/kg triadimefon PO; 3) 100 mg/kg MPT; and 4) both MPT and triadimefon. A similar design was used to determine the interaction between triadimefon and reserpine (0.62 mg/kg), MPT and d-amphetamine (1.5 mg/kg), and reserpine and methylphenidate (5.0 mg/kg). In the first experiment MPT did not block the increased motor activity produced by triadimefon (i.e., both triadimefon alone and MPT in combination with triadimefon produced significant increases in motor activity). MPT did, however, block d-amphetamine-induced hyperactivity. Since MPT did not antagonize the effect of triadimefon, these data suggest that increased motor activity produced by triadimefon is not mediated through release of newly synthesized catecholamines. In contrast, pretreatment with reserpine blocked the hyperactivity induced by both triadimefon and methylphenidate, which suggests that triadimefon-induced hyperactivity may be due to an interaction with CNS catecholamines stored in reserpine-sensitive pools.The research described in this article has been reviewed by the Health Effects Research Laboratory, US Environmental Protection Agency, and approved for publication. Approval does not signify that the contents necessarily reflect the views and policies of the Agency nor does mention of trade names or commercial products constitute endorsement or recommendation for use. Presented in part at the Annual Meeting of the Society for Neuroscience, New Orleans, LA, November, 1987  相似文献   
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Formetanate (FMT) is a formamidine acaricide/insecticide with a carbamate moiety in its molecular structure. FMT-induced lethality is reportedly due to inhibition of acetylcholinesterase. Here we report evidence of the neurochemical basis for the sublethal, behavioral effects of FMT in rats. In this experiment, 0.5 mg/kg of FMT (5 min before the 55-min test session) produced a pronounced suppression of response rates in rats trained to lever-press under a multiple fixed-interval 1-min fixed-interval 5-min schedule of milk reinforcement. Injections of scopolamine (0.1 mg/kg) and methylscopolamine (0.1 mg/kg) 15 min before FMT blocked the response rate suppression, whereas pretreatment with either mecamylamine (2 mg/kg) or hexamethonium (2 mg/kg) did not. These data suggest that FMT acts as an indirect agonist on central and peripheral muscarinic receptors, by inhibiting acetylcholinesterase, to produce changes in schedule-controlled responding.  相似文献   
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ObjectivesAsthma is one of the most common major noncommunicable diseases in the world and affects individuals of all ages. Medication is used to achieve and maintain quality of life (QOL) for people with asthma. Telehealth interventions offer optimized and personalized symptom monitoring with timely treatment adjustment and the potential to increase medication adherence for individuals with asthma. This study examines and synthesizes the available data on the change in the QOL for patients with asthma who use interactive telehealth interventions, and identifies the most effective telehealth modalities used for intervention in this area.MethodsLiterature searches were conducted in 5 databases in November 2018 for studies measuring a change in QOL for patients with asthma. Study QOL outcomes, where possible, were pooled in a meta-analysis.ResultsSeventeen publications (describing 16 studies) comprising 2015 patients were included. Based on a meta-analysis, interactive telehealth interventions can improve QOL outcomes for people living with asthma, although the improved effects may be small: web portals (0.51, 95% confidence interval [CI] –0.00 to 1.03), interactive smartphone apps (0.30, 95% CI –0.16 to 0.76) and remote monitoring (standardized mean difference 0.20, 95% CI –0.11 to 0.52). Intervention delivery modalities identified include interactive web portals, smartphone apps, and remote monitoring programs.ConclusionsThe findings provide a comprehensive overview of the available literature on interactive telehealth interventions, including interactive web portals, smartphone apps, and remote monitoring programs. These findings demonstrated that a positive change in QOL can be attributed to these interventions and provide evidence for the implementation of telehealth interventions for individuals with asthma.  相似文献   
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OBJECTIVES: To determine whether South African youths living in communities that had either of two youth human immunodeficiency virus (HIV) prevention interventions [(a) loveLife Youth Centre or (b) loveLife National Adolescent Friendly Clinic Initiative] would have a lower prevalence of HIV, sexually transmitted infections (STIs), and high risk sexual behaviours than communities without either of these interventions. METHODS: In 2002 the baseline survey of a quasi-experimental, community-based study was conducted in South Africa. In total 33 communities were included in three study arms (11 communities per study arm). The final sample included 8735 youths aged 15-24 years. All participants took part in a behavioural interview and were tested for HIV, gonorrhoea (Neisseria gonorrhoeae) and Chlamydia (Chlamydia trachomatis). RESULTS: HIV prevalence was 20.0% among females and 7.5% among males (OR 3.93 95% CI 2.51-6.15). There were no significant differences between study arms for HIV, NG or CT prevalence at baseline. In multiple regression analyses, HIV was significantly associated with NG infection (OR 1.96 95% CI 1.24-3.12) but not with CT infection. Youths who reported >1 lifetime partner were also significantly more likely to be infected with HIV (OR 1.98 95% CI 1.55-2.52), as were those who reported ever having engaged in transactional sex (OR 1.86 P = 0.02) or having had genital ulcers in the past 12 months (OR 1.71 P < or = 0.001). CONCLUSIONS: HIV prevention programmes must ensure that gender inequities that place young women at greater risk for HIV infection are urgently addressed and they must continue to emphasize the importance of reducing the number of sexual partners and STI treatment.  相似文献   
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The profile of patients on chronic dialysis has shifted. There is a growing group of older patients with comorbid dementia and ESKD, who are at risk of overuse, underuse, and misuse of dialysis. Policy is lacking to help guide treatment decisions in this group. This paper explores clinical considerations specific to patients with comorbid ESKD and dementia. These include: the impact of comorbid dementia on dialysis effectiveness and feasibility; burden of care issues that are specific to patients with dementia; and capacity, autonomy, and consent. A better understanding of these issues may help guide discussions and decision making about treatment. For some older patients with multiple comorbidities including dementia, dialysis does not provide survival or quality of life benefit compared to medical management. These patients also experience additional treatment burden due to a ‘dementia unfriendly’ environment. However, exceptions may include patients who are younger, more independent, and have fewer comorbidities. Patients with dementia are often inappropriately assumed to lack capacity to participate in treatment decision making, and are at risk of having their preferences overlooked. Many patients with mild‐to‐moderate dementia remain capable of reporting their preferences and quality of life, and should always be involved in treatment discussions where possible.  相似文献   
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OBJECTIVES: To determine the prevalence of HIV infection, HIV risk factors, and exposure to national HIV prevention programs, and to identify factors associated with HIV infection among South African youth, aged 15-24 years. DESIGN: A cross-sectional, nationally representative, household survey. METHODS: From March to August 2003 we conducted a national survey of HIV prevalence and sexual behavior among 11 904 15-24 year olds. Multivariable models for HIV infection were restricted to sexually experienced youth. RESULTS: Young women were significantly more likely to be infected with HIV in comparison with young men (15.5 versus 4.8%). Among men, a history of genital ulcers in the past 12 months was associated with HIV infection [adjusted odds ratio (AOR), 1.91; 95% confidence interval (CI), 1.04-3.49) whereas among women a history of unusual vaginal discharge in the past 12 months was associated with HIV infection (AOR, 1.75; 95% CI, 1.26-2.44). Young women with older partners were also at increased risk of HIV infection. Among both men and women, increasing partner numbers and inconsistent condom use were significantly associated with HIV infection. Males and females who reported participation in at least one loveLife program were less likely to be infected with HIV (AOR, 0.60; 95% CI, 0.40-0.89; AOR, 0.61; 95% CI, 0.43-0.85, respectively). CONCLUSION: This survey confirms the high HIV prevalence among young people in South Africa and, in particular, young women's disproportionate risk. Programs for youth must continue to promote partner reduction, consistent condom use and prompt treatment for sexually transmitted infections while also addressing contextual factors that make it difficult for them to implement behavior change.  相似文献   
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