全文获取类型
收费全文 | 5979篇 |
免费 | 337篇 |
国内免费 | 15篇 |
专业分类
耳鼻咽喉 | 49篇 |
儿科学 | 317篇 |
妇产科学 | 80篇 |
基础医学 | 662篇 |
口腔科学 | 114篇 |
临床医学 | 561篇 |
内科学 | 1381篇 |
皮肤病学 | 80篇 |
神经病学 | 526篇 |
特种医学 | 144篇 |
外科学 | 1042篇 |
综合类 | 135篇 |
一般理论 | 3篇 |
预防医学 | 367篇 |
眼科学 | 143篇 |
药学 | 316篇 |
中国医学 | 18篇 |
肿瘤学 | 393篇 |
出版年
2023年 | 60篇 |
2022年 | 72篇 |
2021年 | 197篇 |
2020年 | 125篇 |
2019年 | 171篇 |
2018年 | 204篇 |
2017年 | 140篇 |
2016年 | 165篇 |
2015年 | 152篇 |
2014年 | 236篇 |
2013年 | 258篇 |
2012年 | 411篇 |
2011年 | 462篇 |
2010年 | 242篇 |
2009年 | 229篇 |
2008年 | 343篇 |
2007年 | 327篇 |
2006年 | 330篇 |
2005年 | 282篇 |
2004年 | 274篇 |
2003年 | 285篇 |
2002年 | 226篇 |
2001年 | 130篇 |
2000年 | 113篇 |
1999年 | 108篇 |
1998年 | 51篇 |
1997年 | 38篇 |
1996年 | 30篇 |
1995年 | 21篇 |
1994年 | 28篇 |
1993年 | 23篇 |
1992年 | 48篇 |
1991年 | 43篇 |
1990年 | 41篇 |
1989年 | 39篇 |
1988年 | 42篇 |
1987年 | 23篇 |
1986年 | 27篇 |
1985年 | 42篇 |
1984年 | 29篇 |
1983年 | 25篇 |
1982年 | 21篇 |
1981年 | 16篇 |
1980年 | 14篇 |
1979年 | 19篇 |
1978年 | 17篇 |
1977年 | 16篇 |
1976年 | 14篇 |
1974年 | 19篇 |
1971年 | 15篇 |
排序方式: 共有6331条查询结果,搜索用时 31 毫秒
1.
ABSTRACT Informal settlements remain a public health problem as they lack basic infrastructure. Furthermore, it is challenging to enforce public health regulations and protocols to prevent the spread of infection during a pandemic. This paper was set out to explore the impact of lockdown during COVID-19 among people living in informal settlements. An exploratory qualitative design was utilised. Purposive sampling was used to select research participants. In-depth one-to-one interviews were held involving 30 research participants through a WhatsApp online telephone platform. A thematic approach underpinned by the four stages of data analysis in interpretive phenomenological analysis was utilised to analyse the data. The study found that during the the research participants were affected by lack of space to practice social distancing, over-burdened infrastructure, lack of savings, loss of income and shortage of food, hunger and diseases, anxiety and depression and poor access to education. There is a need to prioritise the needs of informal settlers and endeavour to establish permanent homes. Health promotion and communication initiatives and pandemic awareness programmes are needed to mitigate the impact of lockdown during a pandemic in informal settlements. 相似文献
2.
3.
A total of 117 manic-depressives who had been on lithium for a mean duration of 4.7 years were examined before lithium therapy and subsequently at intervals. Information relating to pre-lithium height and weight and current weight were determined and used to calculate the body mass index (BMI) for each individual. Other relevant variables such as age, sex, cumulative lithium dose, duration of therapy, thyroid profile and serum lithium levels were recorded. The results indicated that, although there was a nonsignificant increase in BMI for the whole population, lithium and sex were not significant predictors of any increase in BMI. In nearly 27% of patients BMI actually slightly decreased during lithium therapy. The overall conclusions from this study are that, in the population studied, lithium may not have exerted any pharmacological effects to increase BMI. 相似文献
4.
Society of Geriatric Cardiology 总被引:3,自引:0,他引:3
5.
Matteo Tosato Valentina Zamboni Alessandro Ferrini Matteo Cesari 《Clinical Interventions in Aging》2007,2(3):401-412
Aging is commonly defined as the accumulation of diverse deleterious changes occurring in cells and tissues with advancing age that are responsible for the increased risk of disease and death. The major theories of aging are all specific of a particular cause of aging, providing useful and important insights for the understanding of age-related physiological changes. However, a global view of them is needed when debating of a process which is still obscure in some of its aspects. In this context, the search for a single cause of aging has recently been replaced by the view of aging as an extremely complex, multifactorial process. Therefore, the different theories of aging should not be considered as mutually exclusive, but complementary of others in the explanation of some or all the features of the normal aging process. To date, no convincing evidence showing the administration of existing “anti-aging” remedies can slow aging or increase longevity in humans is available. Nevertheless, several studies on animal models have shown that aging rates and life expectancy can be modified. The present review provides an overlook of the most commonly accepted theories of aging, providing current evidence of those interventions aimed at modifying the aging process. 相似文献
6.
Francesco Landi Ettore Capoluongo Andrea Russo Graziano Onder Matteo Cesari Paola Lulli Angelo Minucci Marco Pahor Cecilia Zuppi Roberto Bernabei 《Growth hormone & IGF research》2007,17(1):58-66
CONTEXT: Increasing evidences from experimental and human studies suggest that the activity of the growth hormone (GH/insulin-like growth factor-I) axis may contribute to the age-related cognitive decline and poor cognition in late life. OBJECTIVE: The aim of the present study was to evaluate the relationship of total serum free IGF-I and its binding protein-3 with cognitive performance in older persons aged 80 years or older. DESIGN: Data are from baseline evaluation of the ilSIRENTE study (n=353). Cognitive performance was evaluated using five items enclosed in the Minimum Data Set for Home Care assessment form: short-term memory, procedural memory, cognitive skills in daily decision making, verbal expression, comprehension. Free insulin-like growth factor-I (free IGF-I) and IGF-binding protein-3 (IGFBP-3) in blood were measured. Analysis of covariance (ANCOVA) was used to examine the relationship between cognitive impairment and the serum free IGF-I and IGFBP-3 concentrations, after adjustment for potential confounding variables. RESULTS: After adjustment for potential confounders, which included age, gender, education, cerebrovascular disease, ischemic heart disease, congestive heart failure, hypertension, diabetes, depression, Parkinson diseases, thyroid diseases, smoking status, alcohol abuse, body mass index, and number of medications, individuals with verbal expression problems (n=20) and individuals with comprehension problems (n=24) had a significantly lower serum levels of readily dissociable IGF-I than participants without cognitive impairments. The serum IGFBP-3 presented the same behavior of free IGF-I. CONCLUSION: The present study suggests that among old-old subjects living in the community lower levels of total serum free IGF-I and IGFBP-3 are associated with impairment of cognitive performance. This finding suggests that the GH/IGF-I axis may play an important role in the age-related decline of cognitive performance. 相似文献
7.
8.
Olfactory Neuroblastoma and Neuroendocrine Carcinoma of the Anterior Skull Base: Treatment Results at the M.D. Anderson Cancer Center
下载免费PDF全文
![点击此处可从《Skull base》网站下载免费的PDF全文](/ch/ext_images/free.gif)
John R. Austin Hazel Cebrun Mathew M. Kershisnik Adel K. El-Naggar Adam S. Garden Franco DeMonte Lawrence E. Ginsberg Scott M. Lippman Helmuth Goepfert 《Skull base》1996,6(1):1-8
Updated information on the pathologic characterization and treatment of olfactory neurobiastoma (ON) and neuroendocrine carcinoma (NEC) diseases is presented. A series of patients with ON or NEC was evaluated and retrospectively staged using the UCLA system. The parameters evaluated were symptoms, age, sex, risk factor assessment, stage of disease, treatment, and clinical outcome. The median follow-up was 3 years (range, 18 months to 23 years). The predominant therapy (63%) for ON was combined surgery and radiotherapy. Surgery alone or in combination with ancillary treatment was used in 58% of patients with NEC. For the most receat years of the study, patients with NEC have been treated successfully with combined chemotherapy and radiotherapy. Seventy percent of the patients with ON and 75% of the patients with NEC were clinically free of disease during the defined follow-up period. Surgical therapy consisting of a craniofacial resection combined with postoperative radiotherapy has resulted in good local and long-term control of ON. Our experience indicates that combined chemoradiation is an appropriate therapeutic approach for NEC. 相似文献
9.
10.
Said B Iskandar Mathew G Mathai Ryland P Byrd Thomas M Roy 《The Journal of asthma》2004,41(3):337-342
Asthma affects 5%-10% of adults in the United States. Older adults (> 65 years) with asthma have higher rates of fatal asthma than younger adults. The occurrence of a respiratory emergency, such as status asthmaticus, would seem likely to create a situation of cardiopulmonary dysfunction conducive to myocardial ischemia. However, multiple studies of fatal or near-fatal asthma have failed to incriminate myocardial infarction as a contributing factor. We report a patient without underlying coronary artery disease who sustained myocardial injury consistent with myocardial ischemia and infarction during status asthmaticus while receiving recommended treatment without intravenous sympathomimetics or theophylline. 相似文献