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41.
《Free radical research》2013,47(10):1179-1189
Abstract

Aim of the present study was to test, by vitamin E treatment, the hypothesis that muscle adaptive responses to training are mediated by free radicals produced during the single exercise sessions. Therefore, we determined aerobic capacity of tissue homogenates and mitochondrial fractions, tissue content of mitochondrial proteins and expression of factors (PGC-1, NRF-1, and NRF-2) involved in mitochondrial biogenesis. Moreover, we determined the oxidative damage extent, antioxidant enzyme activities, and glutathione content in both tissue preparations, mitochondrial ROS production rate. Finally we tested mitochondrial ROS production rate and muscle susceptibility to oxidative stress. The metabolic adaptations to training, consisting in increased muscle oxidative capacity coupled with the proliferation of a mitochondrial population with decreased oxidative capacity, were generally prevented by antioxidant supplementation. Accordingly, the expression of the factors involved in mitochondrial biogenesis, which were increased by training, was restored to the control level by the antioxidant treatment. Even the training-induced increase in antioxidant enzyme activities, glutathione level and tissue capacity to oppose to an oxidative attach were prevented by vitamin E treatment. Our results support the idea that the stimulus for training-induced adaptive responses derives from the increased production, during the training sessions, of reactive oxygen species that stimulates the expression of PGC-1, which is involved in mitochondrial biogenesis and antioxidant enzymes expression. On the other hand, the observation that changes induced by training in some parameters are only attenuated by vitamin E treatment suggests that other signaling pathways, which are activated during exercise and impinge on PGC-1, can modify the response to the antioxidant integration.  相似文献   
42.
Exercise training has demonstrated cardioprotection effects. However, the exact mechanism behind this effect is not is clear. The present study evaluated the effects of 12 weeks of previous treadmill training on the levels of oxidative damage, antioxidant enzyme activity and injury in the myocardium of rats submitted to infarction induced by isoproterenol (ISO). Isoproterenol treatment (80 mg/kg given over 2 days in two equal doses) caused arrhythmias and 60% mortality within 24 h of the last injection in the control group (C + ISO) group when compared with the saline control group (saline). Creatine Kinase ? MB levels were markedly increased in hearts from ISO-treated animals in the C + ISO group. Twelve weeks of treadmill training reduced superoxide production, lipid peroxidation levels and protein carbonylation in these animals, as well as increasing the activities and expressions of SOD and CAT. Previous training also reduced CK-MB levels and numbers of deaths by 40%, preventing the deleterious effects of ISO. Based on the data obtained in this study, it is suggested that 12-week treadmill training increases antioxidant enzymes, decreases oxidative damage and reduces the degree of infarction induced by ISO in the hearts of male rats.  相似文献   
43.
To clarify changes of neutrophil functions, mental conditions and relationships among them, 19 male elite long‐distance runners participated in this study for 6 months. Examinations, with informed consent, were carried out once a month. According to the results of physical characteristics, it was thought that training intensity was reduced after the main race, Hakone‐Ekiden. Neutrophil functions were estimated by indices of reactive oxygen species production, determined by luminol‐ and lucigenin‐dependent chemiluminescence (LmCL and LgCL, respectively) and cytochrome c reduction methods. The peak times (PT) in LmCL and LgCL (LgPT) were most prolonged in January and December, respectively. The peak heights (PH) in LmCL (LmPH) were enhanced in February. Decreased levels of negative categories in the profile of mood state (POMS) questionnaire and the total mood state (TMS) of POMS were observed in February without significance. Correlation analysis using measured values revealed significant negative correlation between LmPH and negative categories in POMS; however, these correlations were possibly a mere appearance, caused by personal differences. After eliminating personal differences, LgPT correlated positively to depression (p < 0.05), anger (p < 0.05), fatigue (p < 0.01) and TMS (p < 0.05). These results suggest that the mean time from the recognition of foreign matter to the maximum production of superoxide from neutrophils is prolonged in the mentally suppressed conditions found under continuous physical training. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
44.
目的:分析早期强化步行基本功训练对脑卒中预后的影响。方法:选取我院2008年10月一2011年10月收治的176例恢复期脑卒中患者,按照随机数字表分为观察组及对照组,各88例,均接受常规药物治疗和康复训练,观察组在此基础上接受早期强化步行基本功训练,对比两组患者的预后。结果:两组患者治疗后FMA—LE、BBS及MBI评分均见上升,观察组较对照组上升程度更为明显(P〈0.05),T2时期观察组评分亦见升高,而对照组评分与T1时期相比无明显统计学差异(P〉0.05);两组患者治疗后步长、步宽及步速均见上升,观察组较对照组上升程度更为明显(P〈0.05),T2时期观察组步态参数亦见升高,而对照组步态参数与T1时期相比无明显统计学差异(P〉0.05)。结论:早期强化步行基本功训练能够有效改善脑卒中患者下肢运动功能和平衡能力,保证治疗后步行功能,避免生活质量下降,该康复方法值得广泛推广。  相似文献   
45.
The aim of this study was to investigate the heart rate (HR) responses, the rate of perceived exertion (RPE), and the feeling during physical education schooling while performing traditional games activities compared to intermittent exercise. Nineteen pre-pubertal children randomly performed on different days two types of lessons (intermittent running mode vs. traditional Tunisian “Raqassa” game) lasting 12-min each. HR was continuously recorded during both lessons, while ratings of perceived exertion and Feeling values were recorded after the sessions. The mean HR value during the traditional game was significantly higher than during intermittent exercise (p<0.05). Conversely, the perceived exertion score was significantly higher after intermittent exercise than the traditional exercise game (p<0.05), showing that the higher cardiovascular strain of the game was perceived as “lighter” than the run. Simultaneously, the children''s Feeling was significantly higher after the traditional game than intermittent exercise (p<0.001), showing a higher satisfaction from playing with respect to running. Exercise based on the “Raqassa” traditional game could be used in pre-pubertal children as an alternative or as an additional method for suitable cardiovascular stimulation during physical education lessons with lower perceived exertion and better feeling compared to intermittent running.  相似文献   
46.
The objective of this study was to determine the effects of a 10-week dynamic back extension training programme and its effects on back muscle strength, back muscle endurance and spinal range of motion (ROM) for healthy young females. Seventy-three young females (age: 19.32±1.80 years, height: 158.89±4.71 cm, body weight: 55.67±6.30 kg) volunteered for the study. Prior to the training period, all participants completed anthropometric measurements, back muscle strength and endurance test, lateral bending and spinal ROM measurements. After measurements, the participants were divided into two groups. The exercise group (N:35) performed the dynamic back extension exercise 3 days per week for 10 weeks. The control group (N:38) did not participate in any type of exercise. The mixed design ANOVA (group x time) was used to determine the difference in pre- and post-training values. The present findings show that there were significant differences between pre-training and post-training values for back muscle strength and spinal ROM in the exercise group. Following the dynamic strength training programme, back muscle strength and spine ROM values except flexion of the lumbar 5-sacrum 1 (L5-S1) segment of the exercise group showed a significant increase when compared with the pre test values. The control group did not show any significant changes when compared with the pre-training values. The results demonstrate that the 10-week dynamic strength training programme was effective for spinal extension ROM and back muscle strength, but there was no change in back muscle endurance. In this context, this programme could potentially be used to prevent the decrease of spinal ROM as well as provide an increase in the fitness parameters of healthy individuals.  相似文献   
47.
《Anthrozo?s》2013,26(4):352-359
Abstract

Humane education programs often target at-risk children and seek to teach empathy and gentleness with animals, but few of these have been assessed. This prospective, longitudinal study examined the effects of “Teaching Love and Compassion” (TLC), a humane education program employing educational group discussions and dog training for seventh-grade, inner city youth in Los Angeles, California. The TLC program is offered to groups of 10 to 12 students during their three-week vacation at the year-round school. Students for the experimental and control groups were selected from the pool of those scoring below the 25th percentile in reading and mathematics. The study, conducted over a two-year period, assessed four successive sessions, comprising an experimental group of 41 children and a control group of 42 children. In morning sessions, the experimental group had discussions focusing on interpersonal issues and conflict management. In the afternoons they were taught the proper care and obedience training of shelter dogs. Pre-, post-, and follow-up tests, specially developed to accommodate the children's reading ability and scheduling constraints, were given to both the experimental and control groups to assess their knowledge of animal care, conflict management skills, attitudes toward self and others, and fear of dogs. Members of the experimental group increased their understanding of pet care and the needs of animals and retained this information more than did the control group for all four TLC sessions, both at post-testing (F=58.4, p=0.0001) and follow-up testing (F=18.9, p=0.0001). At post-testing, the experimental group showed a trend toward a decreased fear of dogs (F=3.6, p=0.062), that was significant at follow-up testing (F=4.2, p=0.019). For these children who are exposed to daily violence and aggression to people and animals, these modest changes were associated with the three-week intervention.  相似文献   
48.
《Anthrozo?s》2013,26(3):304-317
Abstract

In this study we tested the hypothesis that the process of training a non-human primate (NHP) affects it's general behavior patterns, outside of training. A group of Abyssinian colobus monkeys (Colobus guereza, n = 8), housed at Paignton Zoo, UK, were observed for four 12-day periods. Behaviors were noted prior to training, using positive reinforcement to achieve oral examinations, and each month for three months after training had started. These data were used to construct daily activity budgets and investigate social behaviors (both colobus–colobus and colobus–human). A comparison of these data (using doubly repeated measures MANOVAs) showed activity budget (F(3,3) = 9.8, λ = 0.4, p < 0.001) and colobus-initiated interactions with people (F(3,2) = 16.6, λ = 0.3, p < 0.001) differed significantly across the four observation periods. Resting behavior was negatively correlated with feeding behavior (Pearson: n = 56, r = -0.25, p < 0.05); this relationship was considered to be independent of the onset of training. The significant decline in colobus-initiated interactions with the public appeared to be a direct result of the training.

The results in this study showed that the implementation of training reduced colobus–human interactions. Two reasons are suggested in this paper to account for these unexpected results; either or both of these explanations may be true. The increased level of keeper–colobus interactions necessary for training may have acted to socialize the colobus to humans, so that they habituated to the general presence of humans. Equally, the training sessions may have provided the colobus with predictable interactions with humans that provided rewards, outside of which colobus-initiated interactions were not worthwhile.

Training in this situation was found to be beneficial for the colobus and did not adversely affect the behavior of the colobus outside of the training sessions. It is concluded that caution should be taken when instigating training as part of captive primate management, due to species differences and the paucity of studies that have quantified the impact of training on zoo primate biology. What is greatly needed is more studies which are able to empirically compare the biology (behavior and physiology) of zoo housed primates before and after training has been implemented.  相似文献   
49.
《Anthrozo?s》2013,26(3):255-272
Abstract

Horses are used worldwide for a range of activities. Their usefulness and welfare in these pursuits are strongly influenced by their trainability, which may in turn be influenced by learning ability. Handling and riding horses can expose both handler and horse to a considerable risk of injury. This risk can be reduced by employing correct handling procedures that can facilitate learning in horses. As with all training, efficacy is influenced by consistency and timing. To determine the optimum timing of reinforcement, 16 unweaned naïve foals, that had previously undergone minimal human–animal interaction (i.e., not had a headcollar previously applied), of warmblood (WB; n = 6), thoroughbred (TB; n = 5) or warmblood x thoroughbred (WB x TB; n = 6) breeding were randomly assigned to three treatment groups for testing on ten training days at approximately 14-day intervals. Pressure applied to a headcollar via a lead rope was used as the stimulus for each foal to walk forward, and this was repeated until the foal had walked a distance of 8 m. The effects of three different latencies of negative reinforcement were evaluated by releasing the pressure either immediately: as the first foreleg step commenced (Treatment 1); when the second step of the forelegs was completed (Treatment 2) or when the fourth step of the forelegs was completed (Treatment 3). Each foal's rate of learning was measured by the proportion of correct responses relative to the total number of responses performed. Behavioral responses exhibited (rears, strikes, head shakes, falls, sideways movement and hops) and the steps taken over the distance were also recorded.

Initially, the foals undergoing Treatment 1 appeared to learn more quickly than those foals undergoing Treatments 2 and 3, suggesting that Treatment 1 was associated with the greatest compliance and the quickest learning. However, the foals undergoing Treatment 3 ultimately achieved significantly (p < 0.001) more correct responses, suggesting that the longer delay of reinforcement (i.e., the longer duration of aversive stimulus) may enhance learning via the negative reinforcement inherent in lead training in foals. While some conflict behaviors were shown in all treatment groups, most were exhibited on training day 2. This was reflected in the analysis of composite behaviors performed, with training days 1 and 2 being different (p < 0.001) from training day 3, and training days 1–3 being different (p < 0.001) from training days 4–10. These changes indicate that learning occurred in all treatment groups.

The foals used in this study were sired by five different stallions. While the foals sired by stallion 2 (WB) performed significantly (p < 0.001) more correct responses, those foals sired by WB stallions were significantly (p < 0.001) less likely to perform correct responses when compared with those foals of TB or WB x TB breeding. Colts were significantly (p < 0.001) more likely to perform correct responses than were fillies.  相似文献   
50.
《Anthrozo?s》2013,26(3):196-207
Abstract

In a previous study of canine temperament (Hsu and Serpell 2003), a distinct “trainability” factor was identified, characterized by a dog's willingness to attend to its owner and obey simple commands, combined with a high “fetch” motivation, and low levels of distractibility and/or resistance to correction. This paper explores the distribution of this trait in a large sample of dogs in relation to breed, sex and neuter status. The owners of 1,563 dogs belonging to 11 common breeds were invited to assess them for “trainability” using a standardized questionnaire (C-BARQ©). Highly significant breed differences in trainability were detected. In two breeds with distinct field and show bred lines, show bred dogs obtained significantly lower trainability scores. Although no overall sex differences in trainability were detected, male Dachshunds and West Highland White Terriers were found to be significantly more trainable than females. Neutering was not associated with any differences in trainability in female dogs in any breed, but was associated with positive effects on trainability in male Shetland sheepdogs. The findings suggest that there is scope for improving trainability in most breeds of dog, and emphasize the dangers of generalizing among breeds with respect to sex differences in trainability or the benefits of neutering. The biological basis of the trainability trait is also discussed in light of recent research on the evolution of canine social cognition.  相似文献   
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