全文获取类型
收费全文 | 176935篇 |
免费 | 1029篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 1239篇 |
儿科学 | 6651篇 |
妇产科学 | 3172篇 |
基础医学 | 16686篇 |
口腔科学 | 1547篇 |
临床医学 | 12400篇 |
内科学 | 31449篇 |
皮肤病学 | 660篇 |
神经病学 | 16530篇 |
特种医学 | 8972篇 |
外科学 | 28859篇 |
综合类 | 2320篇 |
预防医学 | 18122篇 |
眼科学 | 2747篇 |
药学 | 9602篇 |
中国医学 | 626篇 |
肿瘤学 | 16389篇 |
出版年
2022年 | 123篇 |
2021年 | 195篇 |
2020年 | 63篇 |
2019年 | 71篇 |
2018年 | 21989篇 |
2017年 | 17401篇 |
2016年 | 19543篇 |
2015年 | 944篇 |
2014年 | 845篇 |
2013年 | 853篇 |
2012年 | 7077篇 |
2011年 | 21113篇 |
2010年 | 18855篇 |
2009年 | 11542篇 |
2008年 | 19566篇 |
2007年 | 21802篇 |
2006年 | 613篇 |
2005年 | 2258篇 |
2004年 | 3460篇 |
2003年 | 4432篇 |
2002年 | 2544篇 |
2001年 | 275篇 |
2000年 | 402篇 |
1999年 | 160篇 |
1998年 | 202篇 |
1997年 | 206篇 |
1996年 | 92篇 |
1995年 | 101篇 |
1994年 | 93篇 |
1993年 | 58篇 |
1992年 | 43篇 |
1991年 | 88篇 |
1990年 | 125篇 |
1989年 | 84篇 |
1988年 | 60篇 |
1987年 | 46篇 |
1986年 | 24篇 |
1985年 | 35篇 |
1983年 | 23篇 |
1982年 | 28篇 |
1980年 | 41篇 |
1970年 | 20篇 |
1969年 | 23篇 |
1939年 | 20篇 |
1938年 | 60篇 |
1937年 | 25篇 |
1935年 | 25篇 |
1934年 | 31篇 |
1932年 | 59篇 |
1930年 | 49篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Su M Liu M Tian DP Li XY Zhang GH Yang HL Fan X Huang HH Gao YX 《European journal of epidemiology》2007,22(1):43-48
The purpose of our study was to investigate the temporal malignant tumor incidence rates among the 70,000 residents at the
relatively isolated Nanao Island in South China Sea. The data on all malignant tumor cases from Nanao Cancer Registry during
1995–2004 were coded, computerized, and analyzed using the software SPSS10.0. The tumor incident cases, crude incident rate,
age-standardized incidence rate, their sex distribution and temporal trend were assessed. A total of 1450 new cancer cases
(990 males and 460 females) were identified. The annual average age-standardized incidence rate (ASR) of malignant tumors
was 208.18/100,000. The age-standardized incidence rate of the ten leading cancers in both sexes combined per 100,000 population
were 74.47 for esophageal cancer (EC), 34.81 for cardiac cancer (CC), 25.66 for liver cancer, 26.01 for lung cancer, 18.52
for stomach cancer, 4.45 for nasopharyngeal cancer, 3.91 for breast cancer, 2.53 for colon/rectum cancer, 2.45 for bladder
cancer and 1.92 for pancreatic cancer. These ten types of cancers make up to 93% of all cancer cases, with EC and CC being
the most prevalent and making up 52% of the total cases. The incidence rates of esophagus, liver, lung, breast, nasopharyngeal,
and colon/rectum cancers showed increasing trends during the period from 1995 to 2004 in Nanao Island. Astounding the EC ASR
were 72–150/100,000 among male and 26–64/100,000 among female in Nanao Island during 1995–2004. The EC incidence rate in Nanao
population is among the highest across the world, which suggests that there are potential genetic and/or environmental factors
affecting this particular population. 相似文献
992.
Annaheim B Rehm J Neuenschwander M Gmel G 《International journal of public health》2007,52(4):233-241
Summary Quitting hash. The readiness for behaviour change among cannabis users in Switzerland.
Objectives: The study aims to identify factors that are associated with the willingness of adolescents and young adults to modify their
cannabis use. It is hypothesized that frequency of use, cannabis-related problems and age of onset are associated with their
willingness to change.
Methods: In 2004, a survey on cannabis use was conducted among 13 to 29 year-olds living in Switzerland. Of the 5025 participants 593
had taken cannabis during the past six months. They were then asked about their willingness to change. Three groups of users
were compared: those not willing to change, those considering change, and those determined to change. Pearson Chi-square-tests
and logistic regressions were performed to test the hypotheses.
Results: Experience of problems motivates users to start thinking about changing their behavior. Frequent use and early onset are associated
with young people not making the transition from considering changing behavior to resolving to do so.
Conclusions: The need to perceive problematic use as a first step towards change and the inhibiting effect of dependencerelated factors
on the transition from consideration to determination calls for tailored intervention approaches that are matched to the willingness
to change.
Eingereicht: 10. Dezember 2005; überarbeitet: 13. September 2006; Angenommen: 6. M?rz 2007 相似文献
993.
Background
Girl Scouting may offer a viable channel for health promotion and obesity prevention programs. This study evaluated the effectiveness of an intervention program delivered through Girl Scout Junior troops that was designed to foster healthful troop meeting environments and increase obesity prevention behaviors at home. 相似文献994.
Feng Xie Shu-Chuen Li Ron Goeree Jean-Eric Tarride Daria O’Reilly Ngai-Nung Lo Seng-Jin Yeo Kuang-Ying Yang Julian Thumboo 《Quality of life research》2008,17(4):595-601
Objective Our aim was to cross-culturally validate Chinese Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) in
patients with knee osteoarthritis (OA) scheduled for total knee replacement in Singapore.
Methods Chinese WOMAC was translated from the original English version following standard guidelines. Patients were asked to complete
a questionnaire containing the WOMAC (twice within 6 days), the Short Form 36 (SF-36), and the EuroQoL EQ-5D. Reliability
was assessed using Cronbach’s alpha and intraclass correlation coefficients (ICC), dimensionality using item-to-domain correlations
and factor analyses. Convergent and discriminant construct validity was assessed using six each a priori hypotheses.
Results Chinese WOMAC was well accepted by the patients in the pilot test. The Chinese and English versions were therefore administered
to a consecutive sample of 131 Chinese- and 127 English-speaking subjects, respectively, with knee OA. Cronbach’s alpha exceeded
0.7 for all domains except for Chinese pain domain, whereas the ICC exceeded 0.7 for all domains. Hypothesized item-to-domain
correlations were observed for all items except for four items in Chinese physical function domain. The factor analyses yielded
seven and five factors with eigenvalues of more than 1.0 in the Chinese and English versions, respectively. A total of 10/12
a priori construct validity hypotheses were satisfied for the Chinese version. Weak correlations between WOMAC pain and SF-36
bodily pain and moderate correlation between WOMAC pain and EQ-5D anxiety/depression were observed.
Conclusions Chinese WOMAC was well accepted and demonstrated acceptable psychometric properties in Singaporean patients with severe knee
OA. 相似文献
995.
Hugenholtz NI Schaafsma FG Nieuwenhuijsen K van Dijk FJ 《International archives of occupational and environmental health》2008,82(1):107-115
OBJECTIVE: An intervention existing of an evidence-based medicine (EBM) course in combination with case method learning sessions (CMLSs) was designed to enhance the professional performance, self-efficacy and job satisfaction of occupational physicians. METHODS: A cluster randomized controlled trial was set up and data were collected through questionnaires at baseline (T0), directly after the intervention (T1) and 7 months after baseline (T2). The data of the intervention group [T0 (n = 49), T1 (n = 31), T2 (n = 29)] and control group [T0 (n = 49), T1 (n = 28), T2 (n = 28)] were analysed in mixed model analyses. Mean scores of the perceived value of the CMLS were calculated in the intervention group. RESULTS: The overall effect of the intervention over time comparing the intervention with the control group was statistically significant for professional performance (p < 0.001). Job satisfaction and self-efficacy changes were small and not statistically significant between the groups. The perceived value of the CMLS to gain new insights and to improve the quality of their performance increased with the number of sessions followed. CONCLUSION: An EBM course in combination with case method learning sessions is perceived as valuable and offers evidence to enhance the professional performance of occupational physicians. However, it does not seem to influence their self-efficacy and job satisfaction. 相似文献
996.
Background
Data on the effect of contraceptive methods, other than the condom, on HIV acquisition is not clear. The aim of this study was to describe hormonal contraceptive use, sexual behaviour and HIV prevalence among women in Cameroon in order to provide baseline information for future analytical studies. 相似文献997.
Annabelle M Wilson Anthea M Magarey Nadia Mastersson 《The international journal of behavioral nutrition and physical activity》2008,5(1):5
Background
Food behaviours, attitudes, environments and knowledge are relevant to professionals in childhood obesity prevention, as are dietary patterns which promote positive energy balance. There is a lack of valid and reliable tools to measure these parameters. The aim of this study was to determine the reliability and relative validity of a child nutrition questionnaire assessing all of these parameters, used in the evaluation of a community-based childhood obesity prevention project. 相似文献998.
Kaja Michalczyk Patrycja Kapczuk Grzegorz Witczak Mateusz Bosiacki Mateusz Kurzawski Dariusz Chlubek Aneta Cymbaluk-Poska 《Nutrients》2022,14(15)
Background: The incidence of endometrial cancer (EC) is still rising. Numerous risk factors including patient characteristics and molecular instability have been identified for EC. The presence of specific molecular markers allows specific diagnostic and prognostic approaches. Several single nucleotide polymorphisms (SNPs) have been identified to influence endometrial cancer risk. Metalloestrogens are metal ions which can mimic estrogen activity; however, their role in uterine pathologies remains unknown. This study aimed to investigate total blood trace elements levels and evaluate the distribution of selected genotypes in GSTP1 and SLC11A2 genes. Methods: This retrospective case-control analysis was carried out in peripheral blood samples of 110 women with endometrial cancer (EC; n = 21), uterine fibroma (n = 25), endometrial polyp (n = 48), and normal endometrium (n = 16). Analysis included measurement of metals and phosphor in serum, and of genetic polymorphisms in GST (rs1695) and SLC11A2 (rs224589) in DNA from white blood cells. Serum trace elements were measured using ICP-OES spectrometry. SNPs were identified using Taq Man real-time PCR genotyping assays. Results: The study confirmed higher age (OR 2.19, 95% CI 1.69–2.24), post-menopausal status (OR 1.89, 95% CI 1.36–1.94), and diabetes type 2 (OR 1.54; 95% CI 0.97–1.72) as independent risk factors for EC. We also found a high level of Cd (OR 1.49; 95% CI 1.31–1.63) and a low level of Co (OR 0.76; 95% CI 0.53–0.59) to be independent risk factors of EC. None of the tested polymorphisms of GSTP1 and SLC11A2 were associated with EC risk. However, high Cd (OR 1.21, 95% CI 1.15–1.29) and Ni (OR 1.07, 95% CI 1.05–1.18) serum levels were significantly associated with a SLC1A2 TG genotype, and high Cd levels with GSTP1 (OR 1.05, 95% CI 1.01–1.13). 相似文献
999.
Nanoindentations and the Raman spectroscopy measurements were carried out on the (001) surface of undoped and S-doped InP crystal. The samples were indented with the maximum load ranging from 15 mN to 100 mN. The phase transition B3→B1 was not confirmed by spectroscopic experiments, indicating a plastic deformation mechanism governed by dislocations activity. Increasing the maximum indentation load shifts and the longitudinal and transverse optical Raman bands to lower frequencies reveals a reduction in the elastic energy stored in the plastic zone right below the indentation imprint. Mechanical experiments have shown that a shift in Raman bands occurs alongside the indentation size effect. Indeed, the hardness of undoped and S-doped InP crystal decreases as a function of the maximum indentation load. 相似文献
1000.
Shen-Yang Lim Ai Huey Tan Susan H. Fox Andrew H. Evans Soon Chai Low 《Current neurology and neuroscience reports》2017,17(1):3
Parkinson’s disease (PD) is a complex motor and non-motor disorder and management is often challenging. In this review, we explore emerging approaches to improve the care of patients, drawing from the literature regarding patient-centred care, patient and caregiver perspectives and priorities, gaps in knowledge among patients and caregivers and the need for accurate information, individual variability in disease manifestations, prognostication of disease course, new developments in health technologies and personalized medicine, specialty care, pharmacological and non-pharmacological management, financial burden, lifestyle and work-related issues, support groups and palliative care. 相似文献