全文获取类型
收费全文 | 154篇 |
免费 | 13篇 |
国内免费 | 6篇 |
专业分类
儿科学 | 14篇 |
妇产科学 | 2篇 |
基础医学 | 15篇 |
口腔科学 | 6篇 |
临床医学 | 17篇 |
内科学 | 32篇 |
皮肤病学 | 6篇 |
神经病学 | 3篇 |
特种医学 | 32篇 |
外科学 | 12篇 |
综合类 | 14篇 |
预防医学 | 9篇 |
眼科学 | 1篇 |
药学 | 7篇 |
中国医学 | 1篇 |
肿瘤学 | 2篇 |
出版年
2022年 | 2篇 |
2021年 | 1篇 |
2020年 | 7篇 |
2019年 | 3篇 |
2018年 | 4篇 |
2017年 | 3篇 |
2016年 | 5篇 |
2015年 | 6篇 |
2014年 | 3篇 |
2013年 | 2篇 |
2012年 | 1篇 |
2011年 | 3篇 |
2010年 | 9篇 |
2009年 | 4篇 |
2008年 | 5篇 |
2007年 | 4篇 |
2006年 | 3篇 |
2005年 | 2篇 |
2004年 | 6篇 |
2003年 | 4篇 |
2001年 | 5篇 |
2000年 | 1篇 |
1999年 | 5篇 |
1998年 | 11篇 |
1997年 | 7篇 |
1996年 | 13篇 |
1995年 | 9篇 |
1994年 | 10篇 |
1993年 | 6篇 |
1992年 | 3篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 4篇 |
1986年 | 2篇 |
1985年 | 3篇 |
1984年 | 4篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1980年 | 4篇 |
1979年 | 1篇 |
1976年 | 1篇 |
排序方式: 共有173条查询结果,搜索用时 15 毫秒
81.
82.
GZ Zhou DD Wong LK Nguyen RM Mendelson 《Journal of Medical Imaging and Radiation Oncology》2010,54(1):17-23
This study aims to evaluate medical student and intern awareness of ionising radiation exposure from common diagnostic imaging procedures and to suggest how education could be improved. Fourth to sixth year medical students enrolled at a Western Australian university and interns from three teaching hospitals in Perth were recruited. Participants were asked to complete a questionnaire consisting of 26 questions on their background, knowledge of ionising radiation doses and learning preferences for future teaching on this subject. A total of 331 completed questionnaires were received (95.9%). Of the 17 questions assessing knowledge of ionising radiation, a mean score of 6.0 was obtained by respondents (95% CI 5.8–6.2). Up to 54.8% of respondents underestimated the radiation dose from commonly requested radiological procedures. Respondents (11.3 and 25.5%) incorrectly believed that ultrasound and MRI emit ionising radiation, respectively. Of the four subgroups of respondents, the intern doctor subgroup performed significantly better (mean score 6.9, P < 0.0001, 95% CI 6.5–7.3) than each of the three medical student subgroups. When asked for the preferred method of teaching for future radiation awareness, a combination of lectures, tutorials and workshops was preferred. This study has clearly shown that awareness of ionising radiation from diagnostic imaging is lacking among senior medical students and interns. The results highlight the need for improved education to minimise unnecessary exposure of patients and the community to radiation. Further studies are required to determine the most effective form of education. 相似文献
83.
Based on a single time-point study of 34 healthy and 19 osteoarthritic knees in three different age groups (early, middle and late adulthood), this paper reports the potential of knee acoustic emission as a biomarker to monitor joint ageing and degeneration. Measurements were made of short transient high frequency acoustic emission signals generated by knee joints under stress during repeated sit-stand-sit movements along with joint angle. A statistically significant feature profile was established using a four-phase model of sit-stand-sit movements and two waveform features. The four-phase movement model is derived from joint angle measurement during repeated sit-stand-sit movements, and it consists of the ascending-acceleration and ascending-deceleration phases in the sit-to-stand movement, followed by the descending-acceleration and descending-deceleration phases in the stand-to-sit movement. The two statistically significant waveform features are extracted from AE measurement during repeated sit-stand-sit movements, and they consist of the peak magnitude value and average signal level of each AE burst. In addition to the use of bilateral plots, statistical distributions and 2D colour histograms to visualise the differences and similarities among participants, use of principal component analysis showed not only distinct data clusters corresponding to participating groups, but also an age- and disease-related trajectory progressing from the early adulthood healthy group to the late adulthood healthy group followed by the middle adulthood osteoarthritic group to the late adulthood osteoarthritic group. Furthermore, this trajectory shows increasing areas for each data cluster, with a highly compact cluster for the early adulthood healthy group at one end and a widely spread cluster for the late adulthood osteoarthritic group at the other end. From these results, a strong basis is formed for further development of knee acoustic emission as a convenient and non-invasive biomarker for quantitative assessment of joint ageing and degeneration. 相似文献
84.
85.
LK Dotterud† JØ Odland‡ ES Falk† 《Journal of the European Academy of Dermatology and Venereology》2004,18(2):131-136
Background The increase in atopic diseases during recent decades has been related to environmental factors such as indoor and outdoor pollution and the ingestion of certain foods. On the other hand, studies from Eastern Europe (with heavy air pollution) have reported a lower prevalence of atopic diseases and sensitization in their schoolchildren than in children living in Western Europe. Objectives This study compares the frequency of atopic diseases and respiratory symptoms in two geographically close arctic areas and points to possible risk factors for development of the diseases. Methods A total of 1734 schoolchildren (1183 in Nikel and 551 in Sør‐Varanger) were studied using identical, four‐page, self‐administered questionnaires. Results Atopic diseases were reported in 38.7% of Norwegian and in 24.2% of Russian children (P < 0.001). Atopic dermatitis (AD) (23.6% vs 7.9%; P < 0.001) and allergic rhinoconjunctivitis (AR) (20.6% vs 14.7%; P < 0.001) occurred more frequently in Sør‐Varanger, whereas ‘self‐reported’ asthma (12.3% vs 13.1%) was similar in both areas. However, respiratory symptoms such as coughing, wheezing, breathlessness and bronchitis were 3–4 times more frequent in Nikel (P < 0.001). Conclusion This study disproves a previous hypothesis, i.e. that air pollution must be a major risk factor for the development of atopic diseases. Nevertheless, respiratory tract symptoms may be provoked by environmental pollution. Possible explanations for the higher frequency of atopic diseases in Sør‐Varanger may be found in socio‐economic and lifestyle differences between the two populations. 相似文献
86.
Dynamic cortical networks of verbal and spatial working memory: effects of memory load and task practice 总被引:8,自引:5,他引:3
Working memory (WM), the ability to briefly retain and manipulate
information in mind, is central to intelligent behavior. Here we take
advantage of the high temporal resolution of electrophysiological measures
to obtain a millisecond timescale view of the activity induced in
distributed cortical networks by tasks that impose significant WM demands.
We examined how these networks are affected by the type and amount of
information to be remembered, and by the amount of task practice. Evoked
potentials (EPs) were obtained from eight subjects performing spatial and
verbal versions of a visual n-back WM task (n = 1, 2, 3) on each of three
testing days. In well-trained subjects, WM tasks elicited transient
responses reflecting different subcomponents of task processing, including
transient (lasting 0.02-0.3 s) task- sensitive and load-sensitive EPs, as
well as sustained responses (lasting 1-1.5 s), including the prestimulus
Contingent Negative Variation (CNV), and post-stimulus frontal and parietal
Slow Waves. The transient responses, with the exception of the P300,
differed between the verbal and spatial task versions, and between trials
with different response requirements. The P300 and the Slow Waves were not
affected by task version but were affected by increased WM load. These
results suggest that WM emerges from the formation of a dynamic cortical
network linking task-specific processes with non-specific, capacity-
limited, higher-order attentional processes. Practice effects on the EPs
suggested that practice led to the development of a more effective
cognitive strategy for dealing with lower-order aspects of task processing,
but did not diminish demands made on higher order processes. Thus a simple
WM task is shown to be composed of numerous elementary subsecond neural
processes whose characteristics vary with type and amount of information
being remembered, and amount of practice.
相似文献
87.
Sai-Cheong Lee Shie-Shian Huang Chao-Wei Lee Chang-Phone Fung Ning Lee Wen-Bin Shieh LK Siu 《BMC infectious diseases》2007,7(1):79
Background
Ertapenem is a once-a-day carbapenem and has excellent activity against many gram-positive and gram-negative aerobic, facultative, and anaerobic bacteria. The susceptibility of isolates of community-acquired bacteremia to ertapenem has not been reported yet. The present study assesses the in vitro activity of ertapenem against aerobic and facultative bacterial pathogens isolated from patients with community-acquired bacteremia by determining and comparing the MICs of cefepime, cefoxitin, ceftazidime, ceftriaxone, ertapenem, piperacillin, piperacillin-tazobactam, ciprofloxacin, amikacin and gentamicin. The prevalence of extended broad spectrum β-lactamases (ESBL) producing strains of community-acquired bacteremia and their susceptibility to these antibiotics are investigated. 相似文献88.
kappa opioid receptors in human microglia downregulate human immunodeficiency virus 1 expression. 总被引:2,自引:0,他引:2 下载免费PDF全文
89.
Bunyatyan N. D. Severina H. I. Mokhamad El Kayal Wassim Zalevskyi S. V. Shtrygol’ S. Yu. Shark Amjad Abu Tsyvunin V. V. Kompantsev D. V. Shevchenko A. M. Kovalenko S. N. Georgiyants V. A. Ogay M. A. Khadzhieva Z. J. 《Pharmaceutical Chemistry Journal》2020,54(1):1-6
Pharmaceutical Chemistry Journal - A search for new anticonvulsants led to a series of 2-(4-oxo-2-thioxo-1,4-dihydro-3(2H)-quinazolinyl)- acetamides that were synthesized by reacting... 相似文献
90.