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   48557篇
  免费   3696篇
  国内免费   192篇
耳鼻咽喉   570篇
儿科学   1021篇
妇产科学   992篇
基础医学   6685篇
口腔科学   1028篇
临床医学   4955篇
内科学   10233篇
皮肤病学   1085篇
神经病学   4646篇
特种医学   1977篇
外国民族医学   2篇
外科学   8699篇
综合类   491篇
一般理论   77篇
预防医学   2825篇
眼科学   942篇
药学   2849篇
中国医学   76篇
肿瘤学   3292篇
  2023年   437篇
  2022年   752篇
  2021年   1739篇
  2020年   1036篇
  2019年   1371篇
  2018年   1550篇
  2017年   1052篇
  2016年   1223篇
  2015年   1413篇
  2014年   1908篇
  2013年   2235篇
  2012年   3654篇
  2011年   3574篇
  2010年   1989篇
  2009年   1773篇
  2008年   2812篇
  2007年   2872篇
  2006年   2672篇
  2005年   2512篇
  2004年   2330篇
  2003年   2114篇
  2002年   1952篇
  2001年   535篇
  2000年   518篇
  1999年   549篇
  1998年   440篇
  1997年   349篇
  1996年   267篇
  1995年   253篇
  1994年   213篇
  1993年   222篇
  1992年   368篇
  1991年   342篇
  1990年   314篇
  1989年   273篇
  1988年   260篇
  1987年   245篇
  1986年   235篇
  1985年   264篇
  1984年   218篇
  1983年   206篇
  1982年   171篇
  1981年   159篇
  1980年   172篇
  1979年   183篇
  1978年   154篇
  1977年   140篇
  1976年   141篇
  1974年   145篇
  1972年   121篇
排序方式: 共有10000条查询结果,搜索用时 203 毫秒
131.
Application of attachment theory to the study of sexual abuse.   总被引:1,自引:0,他引:1  
Research on sexual abuse frequently fails to address the influence of the family as a risk factor for the onset of all kinds of sexual abuse and as a mediator of its long-term effects. Attachment theory provides a useful conceptual framework for understanding the familial antecedents and long-term consequences of sexual abuse. Themes associated with insecure parent-child attachment (rejection, role reversal/parentification, and fear/unresolved trauma) are frequently found in the dynamics of families characterized by sexual abuse, and specific categories of sequelae are related to probable attachment experiences. Implications for intervention and research on sexual abuse are suggested.  相似文献   
132.
133.
134.
Objective: Mental nerve block is frequently used to aid repair of facial lacerations; both percutaneous and intraoral approaches to blocking this nerve are used, but have never been compared. The authors compared the two techniques for pain of administration and effectiveness of anesthesia. Methods: A prospective, randomized, single-blind, crossover study was conducted using ten healthy volunteers aged 22 to 33 years. Patients having prior experience with mental nerve blocks, lidocaine allergy, active oral/facial infection, or previous facial fractures were excluded. Bilateral mental nerve blocks were done using intraoral technique on one side and percutaneous technique on the other. Both techniques were used by the same investigator and were carried out with 27-gauge needles and 2.5 mL of 2% buffered lidocaine at room temperature injected over 20 seconds. The oral mucosa was topically anesthetized with viscous lidocaine for 1 minute prior to intraoral injection. The orders of the blocks and sides of the face anesthetized were randomized. Subjective and objective pain (visual-analog scale), efficacy (anesthesia of lower lip), time to onset, and duration of anesthesia were evaluated. Results: The intraoral technique was subjectively less painful than the percutaneous approach in nine of ten subjects (p = 0.02). Scores on the visual-analog pain scale were significantly lower for the intraoral technique (p = 0.03). Intraoral injection produced lower-lip anesthesia in 10/10 subjects versus 7/10 for percutaneous (p = 0.25). Times to onset (approximately 1–2 minutes) and durations of anesthesia (approximately one hour) were similar for the two techniques. Conclusion: The intraoral approach to the mental nerve block with adjunctive topical anesthesia was subjectively and objectively less painful than the percutaneous approach without adjunctive anesthesia. While the intraoral approach had a greater efficacy of lower-lip anesthesia and a longer duration of action, these differences were not statistically significant.  相似文献   
135.
The purpose of this study was to implement and evaluate a program for obese school children. A pretest-posttest design was utilized. Data was collected related to weight status, skinfold measurements, self-esteem, and nutritional knowledge. A convenience sample of 26 children, in the fourth to sixth grades, completed this 9-week program. The results indicate that self-esteem increased significantly (p less than .001) between the pretest and posttest interval. Weight status and nutritional knowledge showed no improvement. Exercise was difficult to assess on self-report, therefore no conclusions were were drawn in relation to this variable. Future research will be directed toward refining this intervention program.  相似文献   
136.
Behavioral risk factors for injury among rural adolescents.   总被引:5,自引:0,他引:5  
This 3-year, longitudinal, prospective study examined behavioral risk factors for medically attended injuries among a cohort of 758 rural students from Maryland's Eastern Shore region who were 12-14 years of age in 1987. Students were surveyed annually in the eighth, ninth, and tenth grades with a self-administered questionnaire. Information was obtained on the number of injuries experienced, risk-taking behaviors, delinquency, alcohol and drug use, physical exercise and sports, parental supervision, and work experience. Information on the parents' education was obtained from a parental interview. Slightly more than half (53.5%) of the students reported having experienced one or more injuries in the eighth grade as compared with one-third of the students in ninth grade, and 38% of those in the tenth grade. Poisson regression analyses were conducted to examine the association of eighth grade variables with ninth grade injuries and ninth grade variables with tenth grade injuries. Results from these analyses indicated that, in addition to sex and race, a high degree of risk taking, frequent cruising, and having high and low parental supervision in the eighth grade significantly increased the number of injuries in ninth grade. In the tenth grade, risk taking continued to be associated with injuries. In addition, students who reported disciplinary problems in school, working 1-10 hours per week, drinking on 1-2 days during the past month, lifetime use of marijuana equal to 1-5 occasions, and involvement in sports experienced greater numbers of injuries in the tenth grade.  相似文献   
137.
138.
We report on a woman with a an 8-year history of multiple system atrophy with predominance of parkinsonism who developed jaw-locking oromandibular dystonia within hours after insertion of ill-fitting dentures. Dystonia spread rapidly to involve other facial muscles and the larynx causing stridor with respiratory failure necessitating crush intubation.  相似文献   
139.
The opioid transmitters enkephalin and dynorphin are known to regulate pallidal output and consequently cortical excitability. Indeed, abnormal basal ganglia opioid transmission has been reported in several involuntary movement disorders, including levodopa-induced dyskinesias in Parkinson's disease (PD), tardive dyskinesias/dystonia, Huntington's disease, and Tourette's syndrome. Moreover, a previous 11C-diprenorphine PET study investigating levodopa-induced dyskinesias found reduced opioid receptor availability in PD with but not without dyskinesias. We wished to investigate if a similar alteration in basal ganglia opioid binding was present in DYT1 primary torsion dystonia (PTD). Regional cerebral 11C-diprenorphine binding was investigated in 7 manifesting carriers of the DYT1 gene and 15 age-matched normal controls using a region-of-interest (ROI) approach and statistical parametric mapping (SPM). No difference in regional mean 11C-diprenorphine binding was found between DYT1-PTD and controls, and no correlation between the severity of dystonia and opioid binding was seen. We conclude that aberrant opioid transmission is unlikely to be present in DYT1-PTD and altered opioid transmission is not a common mechanism underlying all disorders of involuntary movement.  相似文献   
140.
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