首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   20277篇
  免费   465篇
  国内免费   204篇
  20946篇
  2012年   2053篇
  2011年   2279篇
  2010年   517篇
  2009年   247篇
  2008年   1802篇
  2007年   1760篇
  2006年   1635篇
  2005年   1364篇
  2004年   1173篇
  2003年   1083篇
  2002年   1017篇
  2001年   701篇
  2000年   821篇
  1999年   339篇
  1998年   111篇
  1997年   72篇
  1996年   81篇
  1995年   50篇
  1994年   96篇
  1993年   121篇
  1992年   113篇
  1991年   121篇
  1990年   115篇
  1989年   111篇
  1988年   139篇
  1987年   142篇
  1986年   112篇
  1985年   136篇
  1984年   124篇
  1983年   150篇
  1982年   100篇
  1981年   104篇
  1980年   88篇
  1979年   100篇
  1978年   90篇
  1966年   49篇
  1965年   136篇
  1964年   104篇
  1963年   127篇
  1962年   56篇
  1958年   175篇
  1957年   148篇
  1956年   140篇
  1955年   94篇
  1954年   84篇
  1953年   81篇
  1952年   67篇
  1951年   58篇
  1950年   45篇
  1949年   51篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
992.
Subjects had to judge the size of a tactile stimulus held in the unseen hand, while a visible phantom hand representing that unseen hand held a tactile stimulus of same or different size. No asymmetries in interference effects were found that could be related to hand or handedness. The method lends itself to quantification of virtual reality box illusions and can be used to evaluate the role of experience and sources of variability in the strength of the illusion across subjects.  相似文献   
993.
This article critically re-examines the application of the principle of patient autonomy within bioethics. In complex societies such as those found in North America and Europe health care professionals are increasingly confronted by patients from diverse ethnic, cultural, and religious backgrounds. This affects the relationship between clinicians and patients to the extent that patients' deliberations upon the proposed courses of treatment can, in various ways and to varying extents, be influenced by their ethnic, cultural, and religious commitments. The principle of patient autonomy is the main normative constraint imposed upon medical treatment. Bioethicists typically appeal to the principle of patient autonomy as a means for generally attempting to resolve conflict between patients and clinicians. In recent years a number of bioethicists have responded to the condition of multiculturalism by arguing that the autonomy principle provides the basis for a common moral discourse capable of regulating the relationship between clinicians and patients in those situations where patients' beliefs and commitments do or may contradict the ethos of biomedicine. This article challenges that claim. I argue that the precise manner in which the autonomy principle is philosophically formulated within such accounts prohibits bioethicists' deployment of autonomy as a core ideal for a common moral discourse within multicultural societies. The formulation of autonomy underlying such accounts cannot be extended to simply assimilate individuals' most fundamental religious and cultural commitments and affiliations per se. I challenge the assumption that respecting prospective patients' fundamental religious and cultural commitments is necessarily always compatible with respecting their autonomy. I argue that the character of some peoples' relationship with their cultural or religious community acts to significantly constrain the possibilities for acting autonomously. The implication is clear. The autonomy principle may be presently invalidly applied in certain circumstances because the conditions for the exercise of autonomy have not been fully or even adequately satisfied. This is a controversial claim. The precise terms of my argument, while addressing the specific application of the autonomy principle within bioethics, will resonate beyond this sphere and raises questions for attempts to establish a common moral discourse upon the ideal of personal autonomy within multicultural societies generally.  相似文献   
994.
Using Irish suicide data for the period 1990-1998, the independent effects of month and day adjusting for age, gender, and calendar year effects and distinguishing between holiday and working Mondays were assessed. The male suicide rate was significantly higher on working Mondays (+31%) and Saturdays (+14%), and during April, June, and August (+17%), after adjustment for the other variables. In contrast, female suicide rates were higher only in August (+35%) and exhibited no day effect. Teenage men had a greater elevation of risk on Saturdays, Sundays, and both working and holiday Mondays than any other group. The study findings should be taken into account in the planning of specialized health care services and helplines for suicidal people. Furthermore, the findings provide support for Gabennesch's (1988) broken promise theory and the relationship between dysfunctions of the serotonergic system and suicidal behavior.  相似文献   
995.
Pigeons (Columba livia) searched for food hidden in the center of a square enclosure. On occasional tests without food, the enclosure was (a) unchanged from training (control tests), (b) moved to different corners of the testing room (corner tests), or (c) doubled in size (expansion tests). The birds showed localized search in the center of the enclosure on control and corner tests. On expansion tests, some birds searched near the center of the enclosure, suggesting relative-distance encoding. Other birds searched at locations that maintained the training distance from walls, suggesting absolute-distance encoding. These results are consistent with previous studies on chicks (Gallus gallus) in similar enclosures and contrast with previous results on pigeons' responses to expansions of discrete landmark arrays.  相似文献   
996.
The authors trained 3-, 4-, 7-, and 10-year-old children and adults (Homo sapiens) on a nonverbal serial-order task to respond to 5 items in a specific order. Knowledge of each item's sequential position was then examined using pairwise and triplet tests. Adults and 7- and 10-year-olds performed at high levels on both tests, whereas 3- and 4-year-olds did not. The latency to respond to the first item of a test pair or triplet was linearly related to that item's position in the training series for the 7- and 10-year-olds and adults, but not for the 3- and 4-year-olds. These data suggest that older children and adults, but not younger children, developed a well-integrated internal representation of the serial list.  相似文献   
997.
The number, amplitude, duration, and bout structure of isolation-induced ultrasonic vocalization (USV) of infant rats (Rattus norvegicus) were measured on postnatal Day 10. Measurements were made before and after a brief, 1-min, active interaction with their mother or before and after a "pick-up" control procedure. Consistent with prior studies, the number of USVs emitted was significantly increased in the period following the maternal reunion but not after the control procedure. The average amplitude of USVs was also greater following maternal reunion. Finally, analyses characterizing the bout structure of USV production indicated that the average bout size (i.e. number of USVs/bout) was increased severalfold following the reunion with the mother, accounting for the greater rate of USV production during the second isolation period.  相似文献   
998.
Despite a growing awareness of the unique needs of psychiatric patients with co-occurring substance abuse and dependence disorders (i.e. dual diagnosis), there is a dearth of research investigating the prevalence of dual diagnosis in forensic psychiatric populations. Similarly, little work has been done to determine the implications of dual diagnosis for forensic psychiatric patients. Patients at the Thomas Embling Hospital in Victoria, Australia, were assessed to determine the prevalence of substance abuse disorders and mental illnesses within this population. Results reveal that the majority of patients (approximately 74%) have a lifetime substance abuse or dependence disorder. Information was collected concerning patients' criminal histories and the Level of Service Inventory, Revised, was completed for each patient who participated. Results suggest that patients with both major mental illnesses and substance abuse disorders have more extensive criminal histories and demonstrate a higher level of risks and needs when compared with patients with major mental illness alone. The implications for the development and delivery of effective forensic mental health services that address both co-occurring disorders are also discussed.  相似文献   
999.
Lawyers are often called upon by their older clients to draft contracts, make up wills or powers of attorney, or provide other forms of legal advice or service. With the increasing numbers of older people in the population, the numbers of older clients for legal practitioners is likely to increase. Older people are also at increased risk for impaired cognitive processes that can affect their ability to make reasoned judgements in civil contracts and other legal arrangements. Here we report on the results of a survey of 302 Australian solicitors as to their experience and practices in determining the capacity of older clients to make legal decisions. The responses, reflecting a 20.7% return rate, showed a wide range of experience in conducting capacity assessments, with a mean of 15.7 years (SD = 10.59). There was a very wide range of practices in determining capacity with no consensus. The most frequent form of questions older clients were asked related to personal and family history. Less than one-quarter asked for the rationale of the decision: the most appropriate form of question in the literature. The results suggest a need for further training of solicitors in the assessment of the capacity of older clients to make legal decisions.  相似文献   
1000.
Young and older adults' eye fixations were monitored as they read sentences with temporary ambiguities such as "The experienced soldiers warned about the dangers conducted the midnight raid." Their fixation patterns were similar except that older adults made many regressions. In a 2nd experiment, high- and low-span older adults were compared with high- and low-span young adults. Pint-pass fixations were similar, except low-span readers made many regressions and their total fixation times were longer. High-span readers also used the focus operator "only" (e.g., "Only experienced soldiers warned about the dangers.") to immediately resolve the temporary ambiguities. No age group differences were observed. These results are discussed with reference to theories of the role of working memory in sentence processing.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号