全文获取类型
收费全文 | 3998篇 |
免费 | 530篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 41篇 |
儿科学 | 97篇 |
妇产科学 | 118篇 |
基础医学 | 615篇 |
口腔科学 | 283篇 |
临床医学 | 550篇 |
内科学 | 714篇 |
皮肤病学 | 37篇 |
神经病学 | 268篇 |
特种医学 | 98篇 |
外科学 | 559篇 |
综合类 | 99篇 |
一般理论 | 8篇 |
预防医学 | 436篇 |
眼科学 | 40篇 |
药学 | 294篇 |
中国医学 | 1篇 |
肿瘤学 | 276篇 |
出版年
2021年 | 55篇 |
2020年 | 50篇 |
2019年 | 82篇 |
2018年 | 84篇 |
2017年 | 89篇 |
2016年 | 77篇 |
2015年 | 85篇 |
2014年 | 97篇 |
2013年 | 113篇 |
2012年 | 196篇 |
2011年 | 199篇 |
2010年 | 116篇 |
2009年 | 100篇 |
2008年 | 170篇 |
2007年 | 172篇 |
2006年 | 166篇 |
2005年 | 195篇 |
2004年 | 164篇 |
2003年 | 152篇 |
2002年 | 169篇 |
2001年 | 159篇 |
2000年 | 135篇 |
1999年 | 159篇 |
1998年 | 52篇 |
1997年 | 44篇 |
1996年 | 59篇 |
1995年 | 53篇 |
1994年 | 39篇 |
1993年 | 38篇 |
1992年 | 121篇 |
1991年 | 100篇 |
1990年 | 89篇 |
1989年 | 104篇 |
1988年 | 85篇 |
1987年 | 82篇 |
1986年 | 61篇 |
1985年 | 62篇 |
1984年 | 41篇 |
1983年 | 42篇 |
1982年 | 25篇 |
1981年 | 21篇 |
1979年 | 44篇 |
1978年 | 33篇 |
1977年 | 36篇 |
1976年 | 29篇 |
1975年 | 30篇 |
1971年 | 23篇 |
1970年 | 29篇 |
1969年 | 20篇 |
1967年 | 18篇 |
排序方式: 共有4534条查询结果,搜索用时 15 毫秒
1.
2.
3.
Martina A. Steurer Jean Costello Rebecca J. Baer Scott P. Oltman Sky K. Feuer Tania Pacheco-Werner Elizabeth Rogers Marta M. Jankowska Jessica Block Molly McCarthy Matthew S. Pantell Christina Chambers Kelli K. Ryckman Laura L. Jelliffe-Pawlowski 《Paediatric and perinatal epidemiology》2020,34(2):130-138
4.
Philip J. Lupo Ruth E. Luna-Gierke Tiffany M. Chambers Björn Tavelin Michael E. Scheurer Beatrice Melin Karin Papworth 《International journal of cancer. Journal international du cancer》2020,146(3):791-802
Perinatal factors have been associated with soft tissue sarcomas (STS) in case-control studies. However, (i) the contributions of factors including fetal growth remain unknown, ( ii ) these factors have not been examined in cohort studies and (iii) few assessments have evaluated risk in specific STS subtypes. We sought to identify the role of perinatal and familial factors on the risk of STS in a large population-based birth cohort. We identified 4,023,436 individuals in the Swedish Birth Registry born during 1973–2012. Subjects were linked to the Swedish Cancer Registry, where incident STS cases were identified. We evaluated perinatal and familial factors obtained from Statistics Sweden, including fetal growth, gestational age, and presence of a congenital malformation. Poisson regression was used to estimate incidence rate ratios (IRRs) and 95% confidence intervals (CIs) for associations between perinatal factors and STS overall, as well as by common subtypes. There were 673 individuals diagnosed with STS in 77.5 million person-years of follow-up. Having a congenital malformation was associated with STS (IRR = 1.70, 95% CI: 1.23–2.35). This association was stronger (IRR = 2.90, 95% CI: 1.25–6.71) in recent years (2000–2012). Low fetal growth was also associated with STS during the same time period (IRR = 1.86, 95% CI: 1.05–3.29). Being born preterm was associated with rhabdomyosarcoma (IRR = 1.74, 95% CI: 1.08–2.79). In our cohort study, those with congenital malformations and other adverse birth outcomes were more likely to develop a STS compared to their unaffected contemporaries. These associations may point to disrupted developmental pathways and genetic factors influencing the risk of STS. 相似文献
5.
Grace G. Wong Vincent Ha Michael P. Chu Deonne Dersch-Mills Sunita Ghosh Carole R. Chambers Michael B. Sawyer 《Clinical colorectal cancer》2019,18(1):72-79
Background
First-line adjuvant chemotherapy options for early-stage colorectal cancer (CRC) include CapeOx (capecitabine, intravenous oxaliplatin) and FOLFOX (intravenous 5-fluorouracil, leucovorin, oxaliplatin). Capecitabine is an oral prodrug analog of 5-fluorouracil, and recent studies have suggested that proton pump inhibitors (PPIs) may detrimentally affect capecitabine efficacy. Conversely, some literature suggests that PPIs may negatively affect CRC itself. To gain insight into the nature of PPIs’ effect on capecitabine and CRC, we investigated their effects on effectiveness of CapeOx versus FOLFOX chemotherapy.Patients and Methods
We conducted a retrospective chart review of 389 patients with stage II-III CRC who received adjuvant CapeOx or FOLFOX from 2004 to 2013. Information regarding PPI receipt, chemotherapy, and patient outcomes from medical records was analyzed.Results
Three-year recurrence-free survival was significantly lower in CapeOx-treated PPI recipients than non-PPI recipients (69.5 vs. 82.6%; P = .029). Unadjusted analysis showed that CapeOx-treated PPI recipients were twice as likely to experience cancer recurrence or death as CapeOx-treated non-PPI recipients (hazard ratio = 2.03; 95% confidence interval, 1.06-3.88; P = .033). FOLFOX-treated PPI recipients had a non–statistically significant difference in 3-year recurrence-free survival versus non-PPI recipients (82.9 vs. 61.7%; P = .066) and a non–statistically significant difference in recurrence/death (hazard ratio = 0.51; 95% confidence interval, 0.25-1.06; P = .071). No significant differences were seen in overall survival between groups.Conclusion
Our results suggest PPIs negatively affected recurrence-free survival in CapeOx-treated CRC patients and yielded no significant effects among FOLFOX-treated patients, potentially implicating a pharmacokinetic interaction between PPIs and capecitabine. No overall survival effects were seen. Given PPIs’ widespread use, further studies are required to corroborate our findings. 相似文献6.
Saman K. Hashmi Shoba A. Navai Tiffany M. Chambers Michael E. Scheurer M. John Hicks Rachel E. Rau Maria M. Gramatges 《Pediatric blood & cancer》2020,67(2)
Conjugated hyperbilirubinemia (CHB) and liver transaminase elevation are known complications of acute lymphoblastic leukemia (ALL) therapy, but host risk factors are poorly understood. Among 373 children diagnosed with ALL between 2011 and 2016, clinically significant CHB and transaminase elevation were observed in 15 (4.0%) and 12 (3.2%) children, respectively, during induction and consolidation. Body mass index ≥95th percentile (odds ratio 9.20, 95% confidence interval 2.56–32.96) was the only host factor independently associated with CHB, and no host factors were associated with transaminase elevation. Obese patients warrant closer monitoring of hepatic function to facilitate early intervention prior to the development of severe, adverse hepatic events. 相似文献
7.
Lauren Tingey Britta Mullany Rachel Chambers Ranelda Hastings Angelita Lee Anthony Parker 《AIDS care》2015,27(9):1087-1097
Potential for widespread transmission of HIV/AIDS among American Indian (AI) adolescents exists, yet no evidence-based interventions (EBIs) have been adapted and evaluated with this population. Intensive psychoeducation may improve knowledge and decision-making which could potentially translate to reductions in HIV risk behaviors. A peer group randomized controlled comparison of an adapted EBI vs. control was delivered over an eight-day summer basketball camp in one reservation-based tribal community to adolescents ages 13–19. Outcome data were gathered immediately post-camp and at 6 and 12 months follow-up. Self-selected peer groups were randomized to intervention (n = 138) or control (n = 129) conditions for a total sample of 267 participants (56.2% female), mean age 15.1 years (SD = 1.7). Intervention participants had better condom use self-efficacy post-camp (Adjusted Mean Difference [AMD] = ?0.75, p < 0.005) and at 6 (AMD = ?0.44, p < 0.005) and 12 months (AMD = ?0.23, p < 0.05) follow-up. Intervention participants also had higher HIV prevention and transmission knowledge (post-camp: AMD = 0.07, p < 0.01; 6 months: AMD = 0.06, p < 0.01) were more likely to believe condoms prevent sexually transmitted infections (post-camp: RR = 1.41, p < 0.005; 6 months: RR = 1.34, p < 0.05), to talk with an adult about HIV/AIDS (post-camp: RR=1.78, p < 0.005; 6 months: RR = 1.14, p < 0.005), had higher partner negotiation efficacy related to substance use during sex (post-camp: AMD = 0.37, p < 0.01), and were more likely to intend to use a condom (post-camp: RR = 1.39, p < 0.01). The adapted intervention had short- and medium-term impacts on AI adolescent risk for HIV/AIDS, but attenuated at 12 months. Intervention delivery through a community-based camp is feasible and acceptable with strong retention. Additional study is needed to evaluate the adapted intervention's impact on sexual risk behaviors and if booster sessions and parent involvement translate to long-term impacts. 相似文献
8.
9.
10.