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   7460篇
  免费   759篇
  国内免费   95篇
耳鼻咽喉   35篇
儿科学   238篇
妇产科学   56篇
基础医学   1249篇
口腔科学   215篇
临床医学   789篇
内科学   995篇
皮肤病学   26篇
神经病学   1880篇
特种医学   154篇
外科学   272篇
综合类   439篇
一般理论   2篇
预防医学   1024篇
眼科学   42篇
药学   645篇
  1篇
中国医学   96篇
肿瘤学   156篇
  2024年   21篇
  2023年   174篇
  2022年   207篇
  2021年   474篇
  2020年   426篇
  2019年   377篇
  2018年   290篇
  2017年   339篇
  2016年   358篇
  2015年   379篇
  2014年   494篇
  2013年   795篇
  2012年   366篇
  2011年   412篇
  2010年   257篇
  2009年   318篇
  2008年   343篇
  2007年   265篇
  2006年   240篇
  2005年   228篇
  2004年   172篇
  2003年   165篇
  2002年   158篇
  2001年   126篇
  2000年   103篇
  1999年   77篇
  1998年   65篇
  1997年   57篇
  1996年   54篇
  1995年   82篇
  1994年   48篇
  1993年   50篇
  1992年   50篇
  1991年   36篇
  1990年   33篇
  1989年   28篇
  1988年   32篇
  1987年   25篇
  1986年   20篇
  1985年   27篇
  1984年   33篇
  1983年   17篇
  1982年   13篇
  1981年   23篇
  1980年   16篇
  1979年   14篇
  1978年   5篇
  1977年   6篇
  1976年   7篇
  1968年   2篇
排序方式: 共有8314条查询结果,搜索用时 286 毫秒
71.
The evaluation of behavioral effects is an important component for the in vivo screening of drugs or potentially toxic compounds in mice. Ideally, such screening should be composed of monitoring general health, sensory functions, and motor abilities, right before specific behavioral domains are tested. A rational strategy in the design and procedure of testing as well as an effective composition of different well-established and reproducible behavioral tests can minimize the risk of false positive and false negative results in drug screening. In the present review we describe such basic considerations in planning experiments, selecting strains of mice, and propose groups of behavioral tasks suitable for a reliable detection of differences in specific behavioral domains in mice. Screening of general health and neurophysiologic functions (reflexes, sensory abilities) and motor function (pole test, wire hang test, beam walking, rotarod, accelerod, and footprint) as well as specific hypothesis-guided testing in the behavioral domains of learning and memory (water maze, radial maze, conditioned fear, and avoidance tasks), emotionality (open field, hole board, elevated plus maze, and object exploration), nociception (tail flick, hot plate), psychiatric-like conditions (porsolt swim test, acoustic startle response, and prepulse inhibition), and aggression (isolation-induced aggression, spontaneous aggression, and territorial aggression) are described in further detail. This review is designed to describe a general approach, which increases reliability of behavioral screening. Furthermore, it provides an overview on a selection of specific procedures suitable for but not limited to behavioral screening in pharmacology and toxicology.  相似文献   
72.
Two types of behavioral changes arise in cats after repetitive low-frequency stimulation of the head of the caudate nucleus in cats. Behavioral inhibition is more frequently triggered from the dorsomedial zone of the head, whereas activation phenomena precede depression during stimulation of the ventrolateral zone. The assortment and pattern of stereotyped movements following injection of the minimal effective dose of amphetamine vary in different ways against the background of these changes. After stimulation of the dorsomedial zones of the nucleus stereotypy is first disorganized and then weakened, whereas caudate activation is associated with strengthening of stereotypy.Department of Pharmacology, Chita Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Zakusov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 87, No. 6, pp. 518–521, June, 1979.  相似文献   
73.
Examined the effects of pain symptom severity and patient diagnosticstatus on pediatric staffs' acceptability ratings of 6 interventionsused to treat pediatric pain. Results indicated that (a) extinctionwas significantly less acceptable than all other behavioraland pharmacologic interventions, (b) self-management was moreacceptable than all other interventions with the exception ofcontingency management, (c) accelerative procedures and self-managementinterventions were preferred to pharmacologic treatment, (d)patient diagnostic status and pain symptom severity failed tosignificantly influence treatment ratings, (e) self-managementwas the only intervention differentially rated as a functionof pain symptom severity, and (f) pharmacologic treatment wasdifferentially rated as a function of patient diagnostic status.  相似文献   
74.
目的 比较阿尔茨海默病(Alzheimer Disease,AD)、AD混合型痴呆(Mixed dementia,MD)、血管性痴呆(Vascular dementia,VD)心理和行为症状(Psychological and behavioral symptoms of dementia,PBSD)的特征。方法 AD、MD及VD患者各30名参加本研究。采用Alzheimer病行为症状评定量表(The Begavioral Pathlolgy in Alzheiner Disease Rating Scale,BEHAVE—AD)、Cohen—Masfield激惹性问卷(The Cohen Mansfield Agitation Inventory,CMAI)评定痴呆患者BPSD。结果 AD患者激惹、焦虑与恐惧发生率较高,VD患者无目的游荡发生率、严重程度较低,MD患者BPSD症状无特异性。结论 AD、VD患者BPSD症状有特异性,MD患者BPSD表现无特异性。  相似文献   
75.
This paper presents the response in subjects with asthma to gaseous air-pollution levels, weather, and medicine intake as identified by principal-component analysis and neutral network techniques. Pulmonary function measured by respiratory peak-flow rate in nonallergic asthmatics was associated with ambient, low level, air-pollution concentrations of sulphur dioxide and nitrogen dioxide, temperature, relative humidity, and medicine intake. Results from 27 nonallergic asthmatics aged 18–60 years with well-characterized bronchial asthma and regular medical treatment were analyzed from two cities. During an 8-month period, each subject kept a diary table, which included symptoms, lung function (evening peak flow), medicine intake, and tobbaco smoking.
High intake of medicine and high ambient temperatures correspondend to decreased peak flow. The changes in temperature did not occur in situations with low medicine intake. During frost periods, peak-flow values decreased independently of medicine intake and levels of so2. During other times, increased levels of so2 and no2 increased temperature, and increased intake of medicine, and low relative humidity corresponded to synergistically to decreased peak flow at levels above 40μ/m3.  相似文献   
76.
Examined the utility of a new parent-report measure designedspecifically for pediatric inpatients, the Behavioral Upsetin Medical Patients-Revised (BUMP-R). The BUMP-R was administeredto 151 mothers of hospitalized children ages 4–12 yearsthe day following the child's hospital admission. The BUMP-Rdemonstrated good internal consistency and a factor analysisrevealed four factors identified as negativity/agitation, amiability,dysphoria, and noncom-pliance. Children exhibiting behavioraldistress at home were more likely to experience adjustment problemsupon hospitalization. Demographic and illness-related variableswere not substantial risk factors for hospital adjustment difficulties.  相似文献   
77.
OBJECTIVE: To determine use, appreciation and effectiveness of an electronic health information support system in head and neck (H&N) cancer care. DESIGN: A prospective evaluation study. The evaluated system has four different functions: (1) communication amongst health care providers and between health care providers and patients, (2) information for health care providers and patients, (3) contact with fellow sufferers and (4) monitoring of discharged patients by means of electronic questionnaires. Evaluation of the system was done both objectively using automatically created log files and stored messages, and subjectively by using paper questionnaires from patients and general practitioners (GPs). SETTING: Department of Otorhinolaryngology and Head and Neck Surgery of a tertiary health care centre in the Netherlands. The system was put at patients' disposal for a period of 6 weeks following discharge from the hospital after surgery for H&N cancer, and was additional to standard care. PARTICIPANTS: Head and neck cancer patients, hospital physicians, members of a hospital-based support team, GPs, district nurses and speech therapists. MAIN OUTCOME MEASURES: Actual use of the system by patients and health care providers. Patients' appreciation for each of the system's four different functions. GPs' appreciation for the system. Capability to detect potential patient problems with the system. RESULTS: The system was used by 36 H&N cancer patients, 10 hospital physicians, 2 members of the support team, 8 GPs, 2 district nurses and 2 speech therapists. The total number of patient-sessions was 982: an average of 27.3 sessions per patient during the 6 weeks study period. In total, 456 monitoring questionnaires were completed. The support team in hospital responded with 231 actions. In 16 cases, an extra appointment was made for a patient with the hospital physician. Out of these cases, immediate action was considered necessary eight times. Patients appreciated the system highly, rating it with an average score of 8.0 on a 10-point scale. All patients used the monitoring function, and rated 'monitoring' with a mean score of 8.0 on a 10-point scale. Least used and appreciated was the 'contact with fellow sufferers' function. Only 8 out of possible 36 GPs used the system, rating it with an average of 5.6 on a 10-point scale. CONCLUSIONS: The electronic health information support system was used intensively and highly appreciated by H&N cancer patients. The system enabled the early detection of occurring health problems that required direct intervention. ICT can play an additional role in the management of patients, also in a relatively elderly and computer illiterate patient population.  相似文献   
78.
Summary: Light‐induced reversible changes in elasticity of semi‐interpenetrating network (semi‐IPN) films bearing azobenzene moieties were achieved under both ultraviolet (UV) and visible light irradiation. The semi‐IPN film was prepared by a cationic copolymerization of azobenzene‐containing vinyl ethers in a linear polycarbonate (PC) film as a matrix. When the irradiation was switched on and off, the semi‐IPN film showed rapid reversible deformation with the same behavior occurring over a range of wavelengths, including both the UV and visible regions. The observed reversible deformation of the film was attributed to the decrease in the film's elasticity, which was assumed to be caused by the frequent transcis cycling isomerization of azobenzene moieties taking place during the UV and visible light irradiation. This cycling makes it difficult for the azobenzene groups to aggregate, thus hindering their ability to function as pseudo‐crosslinking points.

  相似文献   

79.
Group treatment for pain and discomfort   总被引:4,自引:0,他引:4  
Rheumatic patients very often suffer from chronic pain and impairment and show psychological reactions as a consequence of their physical condition. These reactions may vary from psychophysiological symptoms to anger, anxiety, or depression. We developed a cognitive-behavioral treatment programme in a group setting format with components of relaxation, cognitive restructuring, and the promotion of well-being. Subjects included in the study were given diagnoses of low back pain, tension headache, rheumatoid arthritis, and ankylosing spondylitis. Treatment effects in different diagnostic groups were compared to each other, supporting the assumption that pain reduction is greatest in low back pain and least in ankylosing spondylitis. Subjects with inflammatory rheumatic diseases showed some improvement in self-reported physical complaints and in their feelings of well-being.  相似文献   
80.
Substance P administered 30 min after the onset of cerebral ischemia improved the neurological status and prevented postischemic hyperactivity in rats with a passive type of behavior; had no effect on the neurological status of rats with an intermediate type of behavior but reduced their postischemic hyperactivity; aggravated the neurological status of rats with an active type of behavior without exerting a significant effect on their behavioral responses; and averted a rise in the level of depression in rats of all three groups. The results of this study indicate that there is a relationship between the type of behavior, manifestations of cerebral ischemia, and the effects of substance P. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N o 8, pp. 132–136, August, 1995 Presented by P. V. Simonov, Member of the Russian Academy of Medical Sciences  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