全文获取类型
收费全文 | 2756篇 |
免费 | 132篇 |
国内免费 | 16篇 |
专业分类
耳鼻咽喉 | 57篇 |
儿科学 | 115篇 |
妇产科学 | 42篇 |
基础医学 | 252篇 |
口腔科学 | 74篇 |
临床医学 | 200篇 |
内科学 | 606篇 |
皮肤病学 | 28篇 |
神经病学 | 159篇 |
特种医学 | 107篇 |
外科学 | 640篇 |
综合类 | 24篇 |
一般理论 | 2篇 |
预防医学 | 212篇 |
眼科学 | 18篇 |
药学 | 115篇 |
中国医学 | 6篇 |
肿瘤学 | 247篇 |
出版年
2024年 | 3篇 |
2023年 | 23篇 |
2022年 | 34篇 |
2021年 | 84篇 |
2020年 | 64篇 |
2019年 | 81篇 |
2018年 | 114篇 |
2017年 | 60篇 |
2016年 | 74篇 |
2015年 | 83篇 |
2014年 | 110篇 |
2013年 | 158篇 |
2012年 | 231篇 |
2011年 | 239篇 |
2010年 | 121篇 |
2009年 | 113篇 |
2008年 | 200篇 |
2007年 | 207篇 |
2006年 | 167篇 |
2005年 | 142篇 |
2004年 | 92篇 |
2003年 | 90篇 |
2002年 | 74篇 |
2001年 | 23篇 |
2000年 | 24篇 |
1999年 | 20篇 |
1998年 | 24篇 |
1997年 | 8篇 |
1996年 | 11篇 |
1995年 | 13篇 |
1994年 | 11篇 |
1993年 | 10篇 |
1992年 | 19篇 |
1991年 | 17篇 |
1990年 | 30篇 |
1989年 | 16篇 |
1988年 | 15篇 |
1987年 | 24篇 |
1986年 | 14篇 |
1985年 | 9篇 |
1984年 | 12篇 |
1978年 | 4篇 |
1977年 | 3篇 |
1975年 | 4篇 |
1974年 | 2篇 |
1973年 | 5篇 |
1972年 | 4篇 |
1971年 | 2篇 |
1969年 | 4篇 |
1967年 | 3篇 |
排序方式: 共有2904条查询结果,搜索用时 15 毫秒
61.
Fevzi Altuntas Naim Ata Tugce Nur Yigenoglu Semih Bascı Mehmet Sinan Dal Serdal Korkmaz Sinem Namdaroglu Abdulkadir Basturk Tuba Hacıbekiroglu Mehmet Hilmi Dogu İlhami Berber Kursat Dal Kerem Kınık İbrahim Haznedaroglu Fatma Meriç Yılmaz İsa Kılıç Sinan Demircioğlu Alper Yosunkaya Osman Celik 《Transfusion and apheresis science》2021,60(1):102955
IntroductionPassive antibody therapy has been used to immunize vulnerable people against infectious agents. In this study, we aim to investigate the efficacy of convalescent plasma (CP) in the treatment of severe and critically ill patients diagnosed with COVID-19.MethodThe data of severe or critically ill COVID-19 patients who received anti-SARS-CoV-2 antibody-containing CP along with the antiviral treatment (n = 888) and an age-gender, comorbidity, and other COVID-19 treatments matched severe or critically ill COVID-19 patients at 1:1 ratio (n = 888) were analyzed retrospectively.ResultsDuration in the intensive care unit (ICU), the rate of mechanical ventilation (MV) support and vasopressor support were lower in CP group compared with the control group (p = 0.001, p = 0.02, p = 0.001, respectively). The case fatality rate (CFR) was 24.7 % in the CP group, and it was 27.7 % in the control group. Administration of CP 20 days after the COVID-19 diagnosis or COVID-19 related symptoms were associated with a higher rate of MV support compared with the first 3 interval groups (≤5 days, 6?10 days, 11?15 days) (p=0.001).ConclusionCP therapy seems to be effective for a better course of COVID-19 in severe and critically ill patients. 相似文献
62.
63.
Tineke van de Weijer Esther Phielix Lena Bilet Evan G. Williams Eduardo R. Ropelle Alessandra Bierwagen Roshan Livingstone Peter Nowotny Lauren M. Sparks Sabina Paglialunga Julia Szendroedi Bas Havekes Norman Moullan Eija Pirinen Jong-Hee Hwang Vera B. Schrauwen-Hinderling Matthijs K.C. Hesselink Johan Auwerx Michael Roden Patrick Schrauwen 《Diabetes》2015,64(4):1193-1201
Recent preclinical studies showed the potential of nicotinamide adenine dinucleotide (NAD+) precursors to increase oxidative phosphorylation and improve metabolic health, but human data are lacking. We hypothesize that the nicotinic acid derivative acipimox, an NAD+ precursor, would directly affect mitochondrial function independent of reductions in nonesterified fatty acid (NEFA) concentrations. In a multicenter randomized crossover trial, 21 patients with type 2 diabetes (age 57.7 ± 1.1 years, BMI 33.4 ± 0.8 kg/m2) received either placebo or acipimox 250 mg three times daily dosage for 2 weeks. Acipimox treatment increased plasma NEFA levels (759 ± 44 vs. 1,135 ± 97 μmol/L for placebo vs. acipimox, P < 0.01) owing to a previously described rebound effect. As a result, skeletal muscle lipid content increased and insulin sensitivity decreased. Despite the elevated plasma NEFA levels, ex vivo mitochondrial respiration in skeletal muscle increased. Subsequently, we showed that acipimox treatment resulted in a robust elevation in expression of nuclear-encoded mitochondrial gene sets and a mitonuclear protein imbalance, which may indicate activation of the mitochondrial unfolded protein response. Further studies in C2C12 myotubes confirmed a direct effect of acipimox on NAD+ levels, mitonuclear protein imbalance, and mitochondrial oxidative capacity. To the best of our knowledge, this study is the first to demonstrate that NAD+ boosters can also directly affect skeletal muscle mitochondrial function in humans. 相似文献
64.
65.
Kerem M Ferahkose Z Yilmaz UT Pasaoglu H Ofluoglu E Bedirli A Salman B Sahin TT Akin M 《World journal of gastroenterology : WJG》2008,14(23):3633-3641
AIM: To investigate the roles of the adipocytokines, ghrelin and leptin in gastric cancer cachexia.
METHODS: Resistin, ghrelin, leptin, adiponectin, insulin and insulin-like growth factor (IGF-Ⅰ), were measured in 30 healthy subjects, and 60 gastric cancer patients of which 30 suffered from cancerinduced cachexia and 30 served as a control group. The relationships between hormones, body mass index (BMI) loss ratio, age, gender, and Glasgow Prognostic Score (GPS) were investigated.
RESULTS: Cachexia patients had higher tumor stage and GPS when compared with non-cachexia patients (P 〈 0.05). Ghrelin, resistin, leptin, adiponectin and IGF- Ⅰ, showed a significant correlation with BMI loss ratio and GPS (P 〈 0.05). A strong correlation was seen between GPS and BMI loss (R = -0.570, P 〈 0.0001). Multivariate analysis indicated that BMI loss was significantly independent as a predictor of ghrelin, resistin, leptin and IGF-Ⅰ (P 〈 0.05). Existence of an important significant relationship between resistin and insulin resistance was also noted.
CONCLUSION: These results showed that serum ghrelin, leptin, adiponectin, and IGF-Ⅰ play important roles in cachexia-related gastric cancers. No relationship was found between resistin and cancer cachexia. Also, because of the correlation between these parameters and GPS, these parameters might be used as a predictor factor. 相似文献
METHODS: Resistin, ghrelin, leptin, adiponectin, insulin and insulin-like growth factor (IGF-Ⅰ), were measured in 30 healthy subjects, and 60 gastric cancer patients of which 30 suffered from cancerinduced cachexia and 30 served as a control group. The relationships between hormones, body mass index (BMI) loss ratio, age, gender, and Glasgow Prognostic Score (GPS) were investigated.
RESULTS: Cachexia patients had higher tumor stage and GPS when compared with non-cachexia patients (P 〈 0.05). Ghrelin, resistin, leptin, adiponectin and IGF- Ⅰ, showed a significant correlation with BMI loss ratio and GPS (P 〈 0.05). A strong correlation was seen between GPS and BMI loss (R = -0.570, P 〈 0.0001). Multivariate analysis indicated that BMI loss was significantly independent as a predictor of ghrelin, resistin, leptin and IGF-Ⅰ (P 〈 0.05). Existence of an important significant relationship between resistin and insulin resistance was also noted.
CONCLUSION: These results showed that serum ghrelin, leptin, adiponectin, and IGF-Ⅰ play important roles in cachexia-related gastric cancers. No relationship was found between resistin and cancer cachexia. Also, because of the correlation between these parameters and GPS, these parameters might be used as a predictor factor. 相似文献
66.
Pim B. Olthof Mamoru Miyasaka Bas Groot Koerkamp Jimme K. Wiggers William R. Jarnagin Takehiro Noji Satoshi Hirano Thomas M. van Gulik 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2019,21(3):345-351
Background
Perihilar cholangiocarcinoma (PHC) often requires extensive surgery which is associated with substantial morbidity and mortality. This study aimed to compare an Eastern and Western PHC cohort in terms of patient characteristics, treatment strategies and outcomes including a propensity score matched analysis.Methods
All consecutive patients who underwent combined biliary and liver resection for PHC between 2005 and 2016 at two Western and one Eastern center were included. The overall perioperative and long-term outcomes of the cohorts were compared and a propensity score matched analysis was performed to compare perioperative outcomes.Results
A total of 210 Western patients were compared to 164 Eastern patients. Western patients had inferior survival compared to the East (hazard-ratio 1.72 (1-23-2.40) P < 0.001) corrected for age, ASA score, tumor stage and margin status. After propensity score matching, liver failure rate, morbidity, and mortality were similar. There was more biliary leakage (38% versus 13%, p = 0.015) in the West.Conclusion
There were major differences in patient characteristics, treatment strategies, perioperative outcomes and survival between Eastern and Western PHC cohorts. Future studies should focus whether these findings are due to the differences in the treatment or the disease itself. 相似文献67.
?zgür Er Kerem K?l?? Halil ?brahim K?l?n? Tu?rul Aslan Burak Sa?sen 《The journal of advanced prosthodontics》2015,7(1):15-20
PURPOSE
The aim of this study was to evaluate whether the push-out bond strength varies between oval and circular fiber posts, and to examine the effect on the resin cement thicknesses around the posts.MATERIALS AND METHODS
Eighteen mandibular premolar roots were separated into two groups for oval and circular fiber posts systems. Post spaces were prepared and fiber posts were luted to the post spaces. Roots were cut horizontally to produce 1-mm-thick specimens. Resin cement thicknesses were determined with a metallographic optical microscope and push-out tests were done.RESULTS
No significant differences were observed in terms of push-out bond strength between the oval and circular fiber posts (P>.05) The resin cement thicknesses of the oval posts were greater than those of the circular posts group in the coronal, middle and apical specimens (P<.05).CONCLUSION
In the light of these results, it can be stated that resin cement thickness does not affect the push-out bond strength. 相似文献68.
Nicola Diviani Bas van den Putte Stefano Giani Julia CM van Weert 《Journal of medical Internet research》2015,17(5)
Background
Recent years have witnessed a dramatic increase in consumer online health information seeking. The quality of online health information, however, remains questionable. The issue of information evaluation has become a hot topic, leading to the development of guidelines and checklists to design high-quality online health information. However, little attention has been devoted to how consumers, in particular people with low health literacy, evaluate online health information.Objective
The main aim of this study was to review existing evidence on the association between low health literacy and (1) people’s ability to evaluate online health information, (2) perceived quality of online health information, (3) trust in online health information, and (4) use of evaluation criteria for online health information.Methods
Five academic databases (MEDLINE, PsycINFO, Web of Science, CINAHL, and Communication and Mass-media Complete) were systematically searched. We included peer-reviewed publications investigating differences in the evaluation of online information between people with different health literacy levels.Results
After abstract and full-text screening, 38 articles were included in the review. Only four studies investigated the specific role of low health literacy in the evaluation of online health information. The other studies examined the association between educational level or other skills-based proxies for health literacy, such as general literacy, and outcomes. Results indicate that low health literacy (and related skills) are negatively related to the ability to evaluate online health information and trust in online health information. Evidence on the association with perceived quality of online health information and use of evaluation criteria is inconclusive.Conclusions
The findings indicate that low health literacy (and related skills) play a role in the evaluation of online health information. This topic is therefore worth more scholarly attention. Based on the results of this review, future research in this field should (1) specifically focus on health literacy, (2) devote more attention to the identification of the different criteria people use to evaluate online health information, (3) develop shared definitions and measures for the most commonly used outcomes in the field of evaluation of online health information, and (4) assess the relationship between the different evaluative dimensions and the role played by health literacy in shaping their interplay. 相似文献69.
70.
Jimme K Wiggers Bas Groot Koerkamp Zachri Ovadia Olivier R C Busch Dirk J Gouma Thomas M van Gulik 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2014,16(7):635-640