全文获取类型
收费全文 | 56070篇 |
免费 | 5119篇 |
国内免费 | 375篇 |
专业分类
耳鼻咽喉 | 163篇 |
儿科学 | 1501篇 |
妇产科学 | 2063篇 |
基础医学 | 3994篇 |
口腔科学 | 792篇 |
临床医学 | 4335篇 |
内科学 | 11848篇 |
皮肤病学 | 547篇 |
神经病学 | 4042篇 |
特种医学 | 843篇 |
外国民族医学 | 1篇 |
外科学 | 4964篇 |
综合类 | 1438篇 |
现状与发展 | 4篇 |
一般理论 | 7篇 |
预防医学 | 16545篇 |
眼科学 | 731篇 |
药学 | 2351篇 |
4篇 | |
中国医学 | 61篇 |
肿瘤学 | 5330篇 |
出版年
2024年 | 88篇 |
2023年 | 2563篇 |
2022年 | 3743篇 |
2021年 | 3840篇 |
2020年 | 4258篇 |
2019年 | 2805篇 |
2018年 | 2916篇 |
2017年 | 3285篇 |
2016年 | 3130篇 |
2015年 | 2949篇 |
2014年 | 4811篇 |
2013年 | 3597篇 |
2012年 | 2576篇 |
2011年 | 2376篇 |
2010年 | 2942篇 |
2009年 | 2622篇 |
2008年 | 1519篇 |
2007年 | 1519篇 |
2006年 | 1252篇 |
2005年 | 1065篇 |
2004年 | 847篇 |
2003年 | 817篇 |
2002年 | 775篇 |
2001年 | 749篇 |
2000年 | 657篇 |
1999年 | 641篇 |
1998年 | 408篇 |
1997年 | 372篇 |
1996年 | 328篇 |
1995年 | 292篇 |
1994年 | 204篇 |
1993年 | 167篇 |
1992年 | 251篇 |
1991年 | 231篇 |
1990年 | 201篇 |
1989年 | 165篇 |
1988年 | 184篇 |
1987年 | 58篇 |
1986年 | 17篇 |
1985年 | 28篇 |
1984年 | 38篇 |
1983年 | 29篇 |
1982年 | 20篇 |
1981年 | 21篇 |
1980年 | 26篇 |
1979年 | 16篇 |
1978年 | 16篇 |
1977年 | 14篇 |
1974年 | 15篇 |
1973年 | 14篇 |
排序方式: 共有10000条查询结果,搜索用时 250 毫秒
61.
Danielle E Whittier Elizabeth J Samelson Marian T Hannan Lauren A Burt David A Hanley Emmanuel Biver Pawel Szulc Elisabeth Sornay-Rendu Blandine Merle Roland Chapurlat Eric Lespessailles Andy Kin On Wong David Goltzman Sundeep Khosla Serge Ferrari Mary L Bouxsein Douglas P Kiel Steven K Boyd 《Journal of bone and mineral research》2022,37(3):428-439
Prevalence of osteoporosis is more than 50% in older adults, yet current clinical methods for diagnosis that rely on areal bone mineral density (aBMD) fail to detect most individuals who have a fragility fracture. Bone fragility can manifest in different forms, and a “one-size-fits-all” approach to diagnosis and management of osteoporosis may not be suitable. High-resolution peripheral quantitative computed tomography (HR-pQCT) provides additive information by capturing information about volumetric density and microarchitecture, but interpretation is challenging because of the complex interactions between the numerous properties measured. In this study, we propose that there are common combinations of bone properties, referred to as phenotypes, that are predisposed to different levels of fracture risk. Using HR-pQCT data from a multinational cohort (n = 5873, 71% female) between 40 and 96 years of age, we employed fuzzy c-means clustering, an unsupervised machine-learning method, to identify phenotypes of bone microarchitecture. Three clusters were identified, and using partial correlation analysis of HR-pQCT parameters, we characterized the clusters as low density, low volume, and healthy bone phenotypes. Most males were associated with the healthy bone phenotype, whereas females were more often associated with the low volume or low density bone phenotypes. Each phenotype had a significantly different cumulative hazard of major osteoporotic fracture (MOF) and of any incident osteoporotic fracture (p < 0.05). After adjustment for covariates (cohort, sex, and age), the low density followed by the low volume phenotype had the highest association with MOF (hazard ratio = 2.96 and 2.35, respectively), and significant associations were maintained when additionally adjusted for femoral neck aBMD (hazard ratio = 1.69 and 1.90, respectively). Further, within each phenotype, different imaging biomarkers of fracture were identified. These findings suggest that osteoporotic fracture risk is associated with bone phenotypes that capture key features of bone deterioration that are not distinguishable by aBMD. © 2021 American Society for Bone and Mineral Research (ASBMR). 相似文献
62.
《Journal of stroke and cerebrovascular diseases》2022,31(12):106808
The posterior condylar vein is an emissary vein that connects the extracranial and intracranial venous systems through the posterior condylar canal (PCC). Dural arteriovenous fistulas (DAVF) of the PCC are rare, and only seven cases have been reported. Transvenous embolization (TVE) is the first-line treatment for PCC DAVF and is predominantly performed through the internal jugular vein. Herein, we report a case of PCC DAVF treated with TVE through the deep cervical vein. This is the first case report of a PCC DAVF treated with TVE through the deep cervical vein. 相似文献
63.
64.
65.
66.
67.
68.
《The journal of sexual medicine》2015,12(3):720-727
IntroductionTreatment satisfaction of men receiving phosphodiesterase 5 inhibitors (PDE5) for erectile dysfunction (ED) and their partners is essential to successful long‐term therapy.AimThis study aims to assess treatment satisfaction, in men with a partial response to on‐demand (PRN) PDE5 and their female partners, following tadalafil 5 mg once daily or placebo.MethodsThe study was randomized, double‐blind, parallel, and placebo‐controlled in men primarily with mild to moderate ED. Treatment satisfaction was assessed following a 4‐week maximum dose PRN lead‐in, 4‐week nondrug washout, and treatment through 12 weeks. Men were ≥18 years old with ED for ≥3 months and International Index of Erectile Function Erectile Function score of ≥17 and <26 at screening and <26 following PRN lead‐in.Main Outcome MeasuresTreatment satisfaction was assessed using the Treatment Satisfaction Scale (TSS) for patients and partners. TSS domain scores range from 0 to 100, with higher values indicating greater satisfaction. Statistical comparisons were made using analysis of covariance.ResultsTreatment satisfaction was significantly greater with tadalafil once daily vs. placebo across all TSS domains for both patients and their partners (all P < 0.001). For patients, mean scores for the TSS domains Confidence to Complete Sexual Activity and Satisfaction with Orgasm ranged from 53.7 to 57.8 after the PRN lead‐in and 26.7 to 31.9 following the nondrug washout. Following randomized treatment, scores for tadalafil and placebo were 55.4 and 32.6, respectively, for Confidence to Complete Sexual Activity and 57.5 and 37.9, respectively, for Satisfaction with Orgasm. Results were comparable for other TSS domains and between men and their partners.ConclusionsTreatment satisfaction was comparable for tadalafil 5 mg once daily and PRN PDE5 for both patients and female partners, suggesting that tadalafil once daily is a viable therapy option for men with ED who had a partial response to PRN PDE5 therapy. Burns PR, Rosen RC, Dunn M, Baygani SK, and Perelman MA. Treatment satisfaction of men and partners following switch from on‐demand phosphodiesterase type 5 inhibitor therapy to tadalafil 5 mg once daily. J Sex Med 2015;12:720–727. 相似文献
69.
Peng Li Sha-Sha Tao Meng-Qin Zhao Jun Li Xiu Wang Hai-Feng Pan 《Immunological investigations》2015,44(7):603-615
Objective: Association of matrix metalloproteinases (MMPs) gene polymorphisms with rheumatoid arthritis is controversial. We conduct a meta-analysis to clarify this dispute.Methods: We systematically searched the electronic PUBMED, EMBASE and CNKI databases for research articles about MMPs (MMP-1, MMP-2, MMP-3, MMP-9) gene polymorphisms and rheumatoid arthritis (RA) up to January 2015. According to the heterogeneity, fixed-effects or random-effects models were used to calculate crude odds ratios (ORs) and 95% confidence intervals (95% CIs).Results: A total of 11 articles involving 2143 cases and 2049 controls were included in this meta-analysis. Overall, no significant associations were observed between MMP-1-1607 1G/2G polymorphism and RA. Stratification by ethnicity, no significant associations were observed in Caucasian populations. Similarly, no significant associations were observed between MMP-3-1171 5A/6A, MMP-9-1562 C/T polymorphisms and RA in overall and Caucasian populations, respectively. However, a weak association was found between MMP-2-1306 C/T polymorphism and RA (C vs. T, OR?=?0.813, 95%CI?=?0.694–0.953, p?=?0.010) in overall populations.Conclusions: The present meta-analysis suggests that MMP-1-1607 1G/2G, MMP-3-1171 5A/6A, MMP-9-1562 C/T polymorphisms are not associated with the susceptibility of RA, but MMP-2 -1306 C/T is weakly associated with susceptibility to RA. Further studies with more sample size are needed for definitive conclusions. 相似文献
70.
《Injury》2022,53(9):3047-3051
IntroductionProtective devices such as seat belts and airbags have improved the safety of motor vehicle occupants, but limited data suggest they may be associated with increased blunt bowel (small bowel or colon) injuries (BI). Unfortunately, this risk is unquantified.MethodsWe analyzed the National Trauma Data Bank (2017-2019) using ICD-10 codes to identify adult motor vehicle occupants with BI who underwent surgical repair. We used logistic regression modeling to compare the risk of undergoing surgical repair for BI after using a protective device.ResultsOf 2,848,592 injured patients, 475,546 (16.7%) were motor vehicle occupants. Only 1.2% (n = 5627/475,546) of patients underwent a bowel repair or resection. Using a seat belt only was associated with an adjusted OR of 2.09 (95% CI 1.91, 2.28) for undergoing a bowel repair/resection when adjusting for Injury Severity Score (ISS) and age. Airbag deployment without a seat belt had an adjusted OR of 1.46 (95% CI 1.31, 1.62), while both devices combined conferred an OR of 3.27 (95% CI 3.02, 3.54). However, using a seat belt was protective against death with an OR of 0.50 (95% CI 0.48, 0.53), adjusted for age, sex, Charlson Comorbidity Score, and ISS.ConclusionSeat belts and airbags are essential public health safety interventions and protect against death in motor vehicle-associated injuries. However, patients involved in MVCs with airbag deployment or while wearing a seat belt are at an increased risk of bowel injury requiring surgery compared to unrestrained patients, despite these events being relatively uncommon. 相似文献