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   12651篇
  免费   676篇
  国内免费   168篇
耳鼻咽喉   187篇
儿科学   457篇
妇产科学   125篇
基础医学   1336篇
口腔科学   229篇
临床医学   1927篇
内科学   1510篇
皮肤病学   137篇
神经病学   2398篇
特种医学   222篇
外科学   1177篇
综合类   1147篇
预防医学   1480篇
眼科学   106篇
药学   511篇
  3篇
中国医学   276篇
肿瘤学   267篇
  2024年   21篇
  2023年   280篇
  2022年   529篇
  2021年   670篇
  2020年   587篇
  2019年   654篇
  2018年   653篇
  2017年   476篇
  2016年   471篇
  2015年   419篇
  2014年   876篇
  2013年   953篇
  2012年   665篇
  2011年   859篇
  2010年   611篇
  2009年   555篇
  2008年   627篇
  2007年   552篇
  2006年   430篇
  2005年   344篇
  2004年   251篇
  2003年   234篇
  2002年   202篇
  2001年   148篇
  2000年   163篇
  1999年   122篇
  1998年   110篇
  1997年   101篇
  1996年   76篇
  1995年   87篇
  1994年   89篇
  1993年   66篇
  1992年   48篇
  1991年   62篇
  1990年   42篇
  1989年   39篇
  1988年   46篇
  1987年   39篇
  1986年   32篇
  1985年   55篇
  1984年   51篇
  1983年   25篇
  1982年   21篇
  1981年   16篇
  1980年   15篇
  1979年   21篇
  1978年   19篇
  1977年   22篇
  1976年   19篇
  1974年   14篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
IntroductionIndividuals with the same ability of speech recognition in quiet can have extremely different results in noisy environments.ObjectiveTo standardize speech perception in adults with normal hearing in the free field using the Brazilian Hearing in Noise Test.MethodsContemporary, cross-sectional cohort study. 79 adults with normal hearing and without cognitive impairment participated in the study. Lists of Hearing in Noise Test sentences were randomly in quiet, noise front, noise right, and noise left.ResultsThere were no significant differences between right and left ears at all frequencies tested (paired t  1 test). Nor were significant differences observed when comparing gender and interaction between these conditions. A difference was observed among the free field positions tested, except in the situations of noise right and noise left.ConclusionResults of speech perception in adults with normal hearing in the free field during different listening situations in noise indicated poorer performance during the condition with noise and speech in front, i.e., 0°/0°. The values found in the standardization of the Hearing in Noise Test free field can be used as a reference in the development of protocols for tests of speech perception in noise, and for monitoring individuals with hearing impairment.  相似文献   
2.
3.
4.
学习困难儿童智力及记忆力特征分析   总被引:4,自引:3,他引:1  
目的探讨学习困难儿童的智力、记忆力特征。方法学习困难(LD)根据ICD-10五条诊断标准,精神发育迟滞(MR)根据国际疾病分类第10版(ICD-10)诊断标准,分为实验组LD组;对照组a.正常组,b.弱智组。采用中国韦氏儿童智力量表进行智力测验,记忆力测验采用中国科学研究院编制的临床记忆量表。结果LD组与正常对照组在语言智商、操作智商、总智商[(86.23±10.65)分,(87.44±12.59)分,(84.09±13.96)分vs(102.27±10.21)分,(103.22±11.65)分,(103.28±9.88)分]及分测验值差异均有显著性(P<0.01);LD组儿童VIQ与PIQ相距一个标准差以上的比率明显高于对照组(2=9.29,P<0.01),也较MR对照组多(2=4.29,P<0.05)。LD组记忆商(MQ)明显低于正常对照组(P<0.01)。结论LD儿童智商、记忆商水平低于正常儿童,且存在明显智力结构发展不平衡。  相似文献   
5.
Background and objective  The purpose of this study is to assess whether Chinese children with high apnea–hypopnea index (AHI) are sleepier by a modified Epworth Sleepiness Scale (ESS). Materials and methods  Records were retrospectively reviewed. We included children who were between 3 and 12 years old, admitted for overnight polysomnogram because of suspected obstructive sleep apnea syndrome (OSAS). A modified ESS was used to assess excessive daytime sleepiness (EDS) of the children. Results  One hundred ninety-two Chinese children were included. Children with high AHI, defined as AHI > 5.0, were sleepier than children with AHI less than or equal to 5. After adjustment by age, gender, and obesity, children with high AHI remained significantly sleepier. Modified ESS was significantly correlated with AHI (rho = 0.124, 95% CI = 0.004–0.281). Modified ESS score of >8 was the best cutoff point with the sensitivity and specificity of 0.29 and 0.91, respectively. The odds ratio of children with modified ESS > 10 having high AHI was 4.231 (95%CI = 1.248 to 14.338) and children with modified ESS > 8 had the highest odds ratio, 4.295(95%CI = 1.66 to 11.1), of having high AHI. Conclusion   Chinese children with high AHI appear to be sleepier than children with low AHI. Children with suspected OSAS and high modified ESS, i.e., ESS > 8, had significantly higher odds ratio of having high AHI. Increased sleepiness is a specific but not a sensitive symptom in snoring children with high AHI. Screening for EDS in snoring children may help us identify those with high AHI and prioritize the management of those children. All authors worked and the study was carried out in Kwong Wah Hospital in Hong Kong. There was no conflict of interest and no specific source of funding for the study.  相似文献   
6.
Objectives –  To assess long‐term functioning and disability after traumatic brain injury (TBI). Material and methods –  Individuals (n = 88) in Norrbotten, northern Sweden, who had been transferred for neurosurgical care were assessed with internationally established TBI outcome measures 6–15 years post‐injury. Results –  There was an improvement in overall outcome from discharge from inpatient rehabilitation to follow‐up. Many individuals had a high degree of motor and cognitive functioning, which enabled them to live independently in their own home without assistance, but there remained a disability related to community reintegration and social participation. This affected their productivity and to some degree their marital stability. The remaining disability and reduced productivity were related to the age at injury and the injury severity. Conclusions –  Our data showed that individuals with a TBI can achieve and maintain a high degree of functioning many years after the injury. Increasing age and a greater injury severity contributed to their long‐term disability.  相似文献   
7.
Flavocoxid (Limbrel), a proprietary mixture of flavonoid molecules (baicalin and catechin), was tested against a traditional nonsteroidal anti-inflammatory drug, naproxen, for the management of the signs and symptoms of moderate osteoarthritis (OA) in humans. Discomfort and global disease activity were used as the primary end points, and safety assessments were also taken for both treatments as a secondary endpoint. In this double-blind study, 103 subjects were randomly assigned to receive either flavocoxid [500 mg twice daily (BID)] or naproxen (500 mg BID) in a 1-month onset of action trial. Outcome measures included the short Western Ontario and McMaster University Osteoarthritis Index, subject Visual Analogue Scale for discomfort and global response, and investigator Visual Analogue Scale for global response and fecal occult blood. Both flavocoxid and naproxen showed significant reduction in the signs and symptoms of knee OA (P ≤ .001). There were no statistically detectable differences between the flavocoxid and naproxen groups with respect to any of the outcome variables. Similarly, there were no statistically detectable differences between the groups with respect to any adverse event, although there was a trend toward a higher incidence of edema and nonspecific musculoskeletal discomfort in the naproxen group. In this short-term pilot study, flavocoxid was as effective as naproxen in controlling the signs and symptoms of OA of the knee and would present a safe and effective option for those individuals on traditional nonsteroidal anti-inflammatory drugs or cyclooxygenase-2 inhibitors. A low incidence of adverse events was reported for both groups.  相似文献   
8.
Laparoscopic procedures continue to gain popularity over traditional open procedures for a number of abdominal and pelvic surgeries. With increasing experience, the application of this technique is rising because it provides an alternative, less invasive, approach to various surgical procedures. Herein, we report our experience with adult patients with polycystic kidney disease, requiring bilateral laparoscopic nephrectomy before renal transplantation.  相似文献   
9.
Causal attributions may interact with other variables to determine staff responses to challenging behaviour. Furthermore, staff perceptions of the causes of challenging behaviour are likely to change as a result of theoretical and practical training. However, there is no established simple method for measuring staff attributions that could facilitate research in these areas. The present paper describes the development and preliminary psychometric analysis of the Challenging Behaviour Attributions Scale (CHABA).  相似文献   
10.
Smoking and raven IQ   总被引:1,自引:0,他引:1  
Nicotine has recently been shown to enhance measures of information processing speed including the decision time (DT) component of simple and choice reaction time and the string length measure of evoked potential waveform complexity. Both (DT and string length) have been previously demonstrated to correlate with performance on standard intelligence tests (IQ). We therefore hypothesised that nicotine is acting to improve intellectual performance on the elementary information processing correlates of IQ. In the current experiment we tested this hypothesis using the Raven Advanced Progressive Matrices (APM) test. APM scores were significantly higher in the smoking session compared to the non-smoking session, suggesting that nicotine acts to enhance physiological processes underlying performance on intellectual tasks.  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