全文获取类型
收费全文 | 1802篇 |
免费 | 82篇 |
出版年
2023年 | 8篇 |
2021年 | 13篇 |
2020年 | 28篇 |
2019年 | 37篇 |
2018年 | 30篇 |
2017年 | 41篇 |
2016年 | 66篇 |
2015年 | 38篇 |
2014年 | 38篇 |
2013年 | 234篇 |
2012年 | 76篇 |
2011年 | 80篇 |
2010年 | 50篇 |
2009年 | 53篇 |
2008年 | 53篇 |
2007年 | 85篇 |
2006年 | 67篇 |
2005年 | 69篇 |
2004年 | 68篇 |
2003年 | 65篇 |
2002年 | 65篇 |
2001年 | 24篇 |
2000年 | 31篇 |
1999年 | 32篇 |
1998年 | 27篇 |
1997年 | 28篇 |
1996年 | 31篇 |
1995年 | 41篇 |
1994年 | 31篇 |
1993年 | 24篇 |
1992年 | 23篇 |
1991年 | 17篇 |
1990年 | 22篇 |
1989年 | 15篇 |
1988年 | 10篇 |
1987年 | 14篇 |
1986年 | 13篇 |
1985年 | 12篇 |
1984年 | 16篇 |
1983年 | 22篇 |
1982年 | 31篇 |
1981年 | 16篇 |
1980年 | 21篇 |
1979年 | 13篇 |
1978年 | 16篇 |
1977年 | 14篇 |
1976年 | 11篇 |
1975年 | 14篇 |
1974年 | 15篇 |
1973年 | 8篇 |
排序方式: 共有1884条查询结果,搜索用时 15 毫秒
101.
Recent behavioral and brain imaging data indicate that performance on explicit tests of episodic memory is associated with interaction between the left and right cerebral hemispheres, in contrast with the unihemispheric basis for implicit tests of memory. In the present work, individual differences in strength of personal handedness were used as markers for differences in hemispheric communication, with mixed-handers inferred to have increased interhemispheric interaction relative to strong right-handers. In Experiment 1, memory for words was assessed via recall or word fragment completion. In Experiment 2, memory for real-world events was assessed via recall. Results supported the hypothesis, in that mixed-handers displayed better episodic memory in comparison with strong right-handers. 相似文献
102.
A dynamic developmental theory of attention-deficit/hyperactivity disorder (ADHD) predominantly hyperactive/impulsive and combined subtypes 总被引:12,自引:0,他引:12
Sagvolden T Johansen EB Aase H Russell VA 《The Behavioral and brain sciences》2005,28(3):397-419; discussion 419-68
Attention-deficit/hyperactivity disorder (ADHD) is currently defined as a cognitive/behavioral developmental disorder where all clinical criteria are behavioral. Inattentiveness, overactivity, and impulsiveness are presently regarded as the main clinical symptoms. The dynamic developmental behavioral theory is based on the hypothesis that altered dopaminergic function plays a pivotal role by failing to modulate nondopaminergic (primarily glutamate and GABA) signal transmission appropriately. A hypofunctioning mesolimbic dopamine branch produces altered reinforcement of behavior and deficient extinction of previously reinforced behavior. This gives rise to delay aversion, development of hyperactivity in novel situations, impulsiveness, deficient sustained attention, increased behavioral variability, and failure to "inhibit" responses ("disinhibition"). A hypofunctioning mesocortical dopamine branch will cause attention response deficiencies (deficient orienting responses, impaired saccadic eye movements, and poorer attention responses toward a target) and poor behavioral planning (poor executive functions). A hypofunctioning nigrostriatal dopamine branch will cause impaired modulation of motor functions and deficient nondeclarative habit learning and memory. These impairments will give rise to apparent developmental delay, clumsiness, neurological "soft signs," and a "failure to inhibit" responses when quick reactions are required. Hypofunctioning dopamine branches represent the main individual predispositions in the present theory. The theory predicts that behavior and symptoms in ADHD result from the interplay between individual predispositions and the surroundings. The exact ADHD symptoms at a particular time in life will vary and be influenced by factors having positive or negative effects on symptom development. Altered or deficient learning and motor functions will produce special needs for optimal parenting and societal styles. Medication will to some degree normalize the underlying dopamine dysfunction and reduce the special needs of these children. The theory describes how individual predispositions interact with these conditions to produce behavioral, emotional, and cognitive effects that can turn into relatively stable behavioral patterns. 相似文献
103.
This article examines whether various cognitive abilities are associated with symptoms of ADHD. Cognitive ability is conceptualized using Cattell-Horn-Carroll (CHC) theory as measured using the Woodcock-Johnson Tests of Cognitive Ability (3rd ed.). This article also examines whether test session behavior mediates the association between cognitive ability and ADHD. Participants are children ages 6 to 12 with (n= 33) and without (n= 19) ADHD. Results show that inattentive symptoms of ADHD are significantly related to the CHC ability of processing speed above and beyond the effect of test session behavior. Symptoms of ADHD (both inattention and hyperactivity/impulsivity) are also significantly associated with visual spatial processing, but this is completely mediated by test session behavior. It is concluded that inattentive symptoms of ADHD are associated with slower processing speed and that this relationship is not explained by test session behavior. 相似文献
104.
105.
106.
This study examined body-esteem in 10-yr.-old children. The study group comprised 960 schoolchildren, 515 girls and 445 boys (M age= 10.4, SD=0.5). Analysis showed that girls who were overweight had more negative body-esteem on all dimensions (weight, appearance, and attribution). The overweight boys had more negative perceptions on only two dimensions (weight and appearance). Twice as many girls perceived themselves as too fat (20%) as too skinny (10%). Of the girls who perceived themselves as fat, only 31% were overweight; similarly only 33% of the boys who perceived themselves as fat were overweight. The children's perception of their weight seemed as important as their actual weight and was associated with their body-esteem in the same way. Although few children had dieted (7% of the girls and 5% of the boys), the ones who had dieted had more negative body-esteem than children who had not dieted. 相似文献
107.
Genetic Cancer Risk Assessment and Counseling: Recommendations of the National Society of Genetic Counselors 总被引:4,自引:0,他引:4
Trepanier A Ahrens M McKinnon W Peters J Stopfer J Grumet SC Manley S Culver JO Acton R Larsen-Haidle J Correia LA Bennett R Pettersen B Ferlita TD Costalas JW Hunt K Donlon S Skrzynia C Farrell C Callif-Daley F Vockley CW;National Society of Genetic Counselors 《Journal of genetic counseling》2004,13(2):83-114
These cancer genetic counseling recommendations describe the medical, psychosocial, and ethical ramifications of identifying at-risk individuals through cancer risk assessment with or without genetic testing. They were developed by members of the Practice Issues Subcommittee of the National Society of Genetic Counselors Cancer Genetic Counseling Special Interest Group. The information contained in this document is derived from extensive review of the current literature on cancer genetic risk assessment and counseling as well as the personal expertise of genetic counselors specializing in cancer genetics. The recommendations are intended to provide information about the process of genetic counseling and risk assessment for hereditary cancer disorders rather than specific information about individual syndromes. Key components include the intake (medical and family histories), psychosocial assessment (assessment of risk perception), cancer risk assessment (determination and communication of risk), molecular testing for hereditary cancer syndromes (regulations, informed consent, and counseling process), and follow-up considerations. These recommendations should not be construed as dictating an exclusive course of management, nor does use of such recommendations guarantee a particular outcome. These recommendations do not displace a health care provider's professional judgment based on the clinical circumstances of a client. 相似文献
108.
Randomized clinical trials remain the most valid method of testing the efficacy and safety of treatments. While efforts to elucidate the genetic and neurodevelopmental bases of autism are underway, clinicians and families are in need of scientifically valid information on how to best treat patients with autism. The effectiveness of many interventions currently used in communities has not been adequately tested. Given the high public health relevance of autism treatment research and the low interest of the pharmaceutical industry in autism, the role of the National Institutes of Health in supporting this research is paramount. Among recently launched initiatives in autism clinical trials, there are the Research Units on Pediatric Psychopharmacology Autism Network and the network of centers for Studies to Advance Autism Research and Treatment. These and other government activities in the area of autism clinical trials are here briefly reviewed. 相似文献
109.
Hollander E Phillips A King BH Guthrie D Aman MG Law P Owley T Robinson R 《CNS spectrums》2004,9(1):49-56
There are specific challenges to studying the design of pharmacologic trials in child/adolescent and adult autism, such as subject stratification and parallel versus crossover designs. This article describes how optimal study design is influenced by subject selection and outcome measures chosen. Lessons learned in study design from the Research Units on Pediatric Psychopharmacology Autism Network trial with risperidone, Seaver Center trials with fluoxetine and valproate, Dartmouth trials with amantadine, and National Institutes of Health secretin trials are highlighted. The Internet System for Assessing Autistic Children system for managing multicenter clinical trials in autism and statistical issues in autism research are also described. 相似文献
110.
Infants' expressions of discrete emotions were coded during the more stressful episodes (4 through 8) of the Strange Situation at 13 and 18 months. The data showed a significant decrease in full-face expressions (more complex configurations of movements) and a significant increase in component expressions (simpler and more constrained patterns of movements). The authors interpreted this trend as a developmental change toward more regulated and less intense emotions. Consistent with this view, the aggregate index of infants' full-face negative emotion expressions, interpreted as reflecting relatively unregulated intense emotions, correlated significantly with maternal ratings of difficult temperament. The authors discuss alternative interpretations of the findings in terms of changes in reactivity/arousability and the emerging capacity for self-regulation. 相似文献