全文获取类型
收费全文 | 2241篇 |
免费 | 134篇 |
国内免费 | 40篇 |
专业分类
耳鼻咽喉 | 17篇 |
儿科学 | 65篇 |
妇产科学 | 57篇 |
基础医学 | 514篇 |
口腔科学 | 25篇 |
临床医学 | 178篇 |
内科学 | 327篇 |
皮肤病学 | 21篇 |
神经病学 | 280篇 |
特种医学 | 30篇 |
外科学 | 126篇 |
综合类 | 96篇 |
预防医学 | 220篇 |
眼科学 | 27篇 |
药学 | 290篇 |
中国医学 | 36篇 |
肿瘤学 | 106篇 |
出版年
2023年 | 27篇 |
2022年 | 45篇 |
2021年 | 57篇 |
2020年 | 81篇 |
2019年 | 76篇 |
2018年 | 89篇 |
2017年 | 91篇 |
2016年 | 78篇 |
2015年 | 85篇 |
2014年 | 128篇 |
2013年 | 210篇 |
2012年 | 114篇 |
2011年 | 135篇 |
2010年 | 103篇 |
2009年 | 118篇 |
2008年 | 144篇 |
2007年 | 106篇 |
2006年 | 82篇 |
2005年 | 99篇 |
2004年 | 65篇 |
2003年 | 45篇 |
2002年 | 46篇 |
2001年 | 27篇 |
2000年 | 42篇 |
1999年 | 19篇 |
1998年 | 28篇 |
1997年 | 23篇 |
1996年 | 19篇 |
1995年 | 26篇 |
1994年 | 17篇 |
1993年 | 25篇 |
1992年 | 20篇 |
1991年 | 10篇 |
1990年 | 8篇 |
1989年 | 9篇 |
1988年 | 9篇 |
1987年 | 6篇 |
1986年 | 12篇 |
1985年 | 25篇 |
1984年 | 12篇 |
1983年 | 8篇 |
1982年 | 8篇 |
1981年 | 7篇 |
1979年 | 8篇 |
1978年 | 7篇 |
1976年 | 2篇 |
1975年 | 3篇 |
1972年 | 2篇 |
1971年 | 2篇 |
1969年 | 2篇 |
排序方式: 共有2415条查询结果,搜索用时 15 毫秒
1.
2.
3.
BackgroundThe diatom test method using sodium hypochlorite (NaClO) was equivalent to the conventional method in water samples. However, the method using NaClO was inferior to the conventional method in lung samples, in which ethanol was used and the reaction with NaClO was longer compared with the method in water samples. Using water samples, we aimed to clarify whether these differences affect the diatom test result.Materials and methodsThirteen water samples from natural water sources were each divided into four parts corresponding to four (2 × 2) digestion methods: 3 “digestion” vs. 1 “digestion” and with ethanol vs. without ethanol. After the base-2 logarithmic transformation, the diatom counts were analyzed using three-way analysis of variance (ANOVA); factor 1 was “digestion times,” factor 2 was “ethanol,” and factor 3 was “sample number,” and the interaction between factors 1 and 2 was also analyzed.ResultsThe geometric means of the diatoms from the 3 “digestion” with ethanol method, the 3 “digestion” without ethanol method, the 1 “digestion” with ethanol method, and the 1 “digestion” without ethanol method were 373.5, 551.8, 436.6, and 522.0, respectively. ANOVA showed a significant difference in factor 2 (P = 1.7 × 10-4). There was no significant difference in factor 1 (P = 0.46), and no significant interaction between factors 1 and 2 (P = 0.13).ConclusionEthanol may decrease the diatom count in the diatom test using NaClO. In contrast, the diatom frustules do not dissolve through three-times digestion using NaClO. 相似文献
4.
Karin E. Bornfeldt MacRae F. Linton Edward A. Fisher John R. Guyton 《Journal of clinical lipidology》2021,15(1):3-17
Clinical effort in lipidology focuses largely on mitigating effects of atherosclerosis, a pathologic process localized to the intimal layer of larger arteries. This JCL Roundtable brings together 3 leading researchers to discuss the current understanding of pathogenesis in atherosclerosis. We begin by recognizing that low density lipoprotein concentrations in arterial intima far exceed concentrations in other connective tissues, consistent with the response-to-retention hypothesis of atherogenesis. High density lipoproteins facilitate reverse cholesterol transport and also have antioxidant and anti-inflammatory roles. New evidence points to remnants of triglyceride-rich lipoproteins as promoters of atherogenesis, highlighted by deleterious effects of apolipoprotein C-III. The multifaceted role of inflammation is becoming clearer through discoveries related to leukocyte recruitment, efferocytosis, resolution of inflammation, and crystal formation. MicroRNAs represent a new, complex mode of gene regulation bearing on lipoprotein and inflammation biology. Progress in understanding atherosclerosis portends a future in which residual risk related to obesity, diabetes, and other factors will yield to new targeted therapies. 相似文献
5.
PurposeThe aim of the present study was to investigate potential anti-inflammatory effects of wet-cupping prior to a moderate-to-vigorous exercise test among martial arts athletes.MethodsTwenty-one male karate athletes voluntarily participated in this study and were randomly divided into 3 groups: vigorous exercise (VE, n = 7), cupping (CT, n = 7) and cupping plus vigorous exercise (VECT, n = 7). Participants in exercise groups performed an exercise test while participants in CT received cupping therapy, and participants in VECT received cupping therapy plus exercise. Inflammatory markers (i.e., interlukin-6, IL-6, and tumor necrosis factor-α, TNF-α) were assessed prior to, immediately, 30 min, and 24 h after cupping therapy, vigorous exercise test, and their combination.ResultsIL-6 values were significantly lower immediately after cupping intervention in CT as compared to baseline (P < 0.025). IL-6 significantly increased immediately and 30 min post-exercise in VE in comparison with baseline (P < 0.025). IL-6 was also significantly higher at 24 h post-exercise in CTVE as compared to baseline (P < 0.025). TNF-α values were significantly lower in CT as compared to VE and CTVE at immediately and 30 min post-exercise (P < 0.01). TNF-α significantly decreased immediately and 30 min after cupping intervention in CT as compared to baseline (P < 0.01). Conversely, TNF-α significantly increased immediately after exercise in VE as compared to baseline (P < 0.025). TNF-α also significantly increased at 30 min and 24 h post-exercise in CTVE in comparison with baseline (P < 0.025).ConclusionOur findings showed that exercise-induced augmentation in inflammatory markers were lower in athletes who received cupping therapy, suggesting such therapy may be an avenue to mitigate the inflammatory response to vigorous exercise among martial arts athletes. A large-scale clinical study is needed to confirm the findings of the present study. 相似文献
6.
7.
Diarrhea predominant irritable bowel syndrome (IBS) is a highly relapsing gastrointestinal disorder decreasing the quality of life. Existing studies indicated that the therapeutic effects maintained for a period of time after the treatments were discontinued (post-treatment therapeutic effects or PTTE). In this study, we aim to assess the PTTE of tongxie. We performed a multiple center, controlled, double blind study of patients with IBS randomized to tongxie (n = 120) or placebo (n = 120) for 4 weeks and followed up for 57 weeks. The primary outcomes were abdominal pains and stool consistency. The secondary outcomes were pain frequency and stool frequency. Tertiary outcomes were adverse effects and global overall symptom. The outcome data were collected at days 1, 2, 3, weeks 1 and 4 during the treatment and at days 1, 2, 3, until week 57 during the post-treatment. Significantly more patients receiving tongxie were clinical responders to the primary and secondary endpoints from day 1 until the end of the treatment. The positive effects of tongxie were maintained until 17–25 weeks after tongxie was discontinued. The relapse-free probabilities in the tongxie group were significantly higher than those in the placebo group (P < .001). Twenty-five weeks after the therapies were discontinued could be considered as IBS natural history. During this period, an average of 53.8–56.3% of patients (pool tongxie and placebo data together) had IBS symptoms (pain scale ≥ 3, stool consistency ≥ 5). In particular, at the end of this study (week 61), 145 (54.2%) patients had IBS symptoms. Our results provide clinical insights into efficient and cost-effective management of refractory IBS, and lend support to the IBS management that the selection of a therapy should consider both its effectiveness during treatment and its PTTE after the treatment. 相似文献
8.
Monique Lewis 《Sociology of health & illness》2019,41(5):831-851
Complementary and alternative medicine (CAM) has developed into a complex and formidable commercial, sociocultural and political force in Australia, and given its influence, it is a relevant subject for scholars, health practitioners, health communicators, journalists, policy‐makers, and consumers of healthcare products and services. This research will consider a relative newcomer to the claims‐making space about CAM in the Australian health media‐scape; the Friends of Science in Medicine (FSM), an activist group of medical practitioners, researchers, and scientists, founded in late 2011. Using content analysis supported by NVivo, I searched for articles specifically referring to FSM and measured the patterns and frequencies of media frames, intonation and sources that are featured in Australian mainstream news reports between December 2011 and April 2017. The negative headlining and intonation of reports predominated, along with framing CAM as part of a lucrative, undisciplined and unethical industry as well as an illegitimate healthcare approach, more broadly. The findings offer insight into how journalists respond, replicate or reconstruct the framings that are provided by an influential and elite group of medical practitioners and scientists, and readdresses issues surrounding the need for more critical health reporting in Australia. 相似文献
9.
Gang Chen Robert W. Cox Daniel R. Glen Justin K. Rajendra Richard C. Reynolds Paul A. Taylor 《Human brain mapping》2019,40(3):1037-1043
One‐sided t‐tests are widely used in neuroimaging data analysis. While such a test may be applicable when investigating specific regions and prior information about directionality is present, we argue here that it is often mis‐applied, with severe consequences for false positive rate (FPR) control. Conceptually, a pair of one‐sided t‐tests conducted in tandem (e.g., to test separately for both positive and negative effects), effectively amounts to a two‐sided t‐test. However, replacing the two‐sided test with a pair of one‐sided tests without multiple comparisons correction essentially doubles the intended FPR of statements made about the same study; that is, the actual family‐wise error (FWE) of results at the whole brain level would be 10% instead of the 5% intended by the researcher. Therefore, we strongly recommend that, unless otherwise explicitly justified, two‐sided t‐tests be applied instead of two simultaneous one‐sided t‐tests. 相似文献
10.
Somayeh Maleki Balajoo Davud Asemani Ali Khadem Hamid Soltanian‐Zadeh 《Human brain mapping》2020,41(15):4264-4287
To estimate dynamic functional connectivity (dFC), the conventional method of sliding window correlation (SWC) suffers from poor performance of dynamic connection detection. This stems from the equal weighting of observations, suboptimal time scale, nonsparse output, and the fact that it is bivariate. To overcome these limitations, we exploited the kernel‐reweighted logistic regression (KELLER) algorithm, a method that is common in genetic studies, to estimate dFC in resting state functional magnetic resonance imaging (rs‐fMRI) data. KELLER can estimate dFC through estimating both spatial and temporal patterns of functional connectivity between brain regions. This paper compares the performance of the proposed KELLER method with current methods (SWC and tapered‐SWC (T‐SWC) with different window lengths) based on both simulated and real rs‐fMRI data. Estimated dFC networks were assessed for detecting dynamically connected brain region pairs with hypothesis testing. Simulation results revealed that KELLER can detect dynamic connections with a statistical power of 87.35% compared with 70.17% and 58.54% associated with T‐SWC (p‐value = .001) and SWC (p‐value <.001), respectively. Results of these different methods applied on real rs‐fMRI data were investigated for two aspects: calculating the similarity between identified mean dynamic pattern and identifying dynamic pattern in default mode network (DMN). In 68% of subjects, the results of T‐SWC with window length of 100 s, among different window lengths, demonstrated the highest similarity to those of KELLER. With regards to DMN, KELLER estimated previously reported dynamic connection pairs between dorsal and ventral DMN while SWC‐based method was unable to detect these dynamic connections. 相似文献