全文获取类型
收费全文 | 191151篇 |
免费 | 47829篇 |
国内免费 | 2839篇 |
专业分类
耳鼻咽喉 | 2148篇 |
儿科学 | 6412篇 |
妇产科学 | 1650篇 |
基础医学 | 37437篇 |
口腔科学 | 7842篇 |
临床医学 | 18519篇 |
内科学 | 38402篇 |
皮肤病学 | 5495篇 |
神经病学 | 28476篇 |
特种医学 | 7192篇 |
外国民族医学 | 22篇 |
外科学 | 19948篇 |
综合类 | 9187篇 |
现状与发展 | 9篇 |
一般理论 | 8篇 |
预防医学 | 10367篇 |
眼科学 | 2068篇 |
药学 | 23639篇 |
7篇 | |
中国医学 | 3659篇 |
肿瘤学 | 19332篇 |
出版年
2024年 | 111篇 |
2023年 | 941篇 |
2022年 | 1732篇 |
2021年 | 3939篇 |
2020年 | 7954篇 |
2019年 | 13277篇 |
2018年 | 12933篇 |
2017年 | 14098篇 |
2016年 | 13294篇 |
2015年 | 13625篇 |
2014年 | 15123篇 |
2013年 | 16787篇 |
2012年 | 14396篇 |
2011年 | 15074篇 |
2010年 | 12764篇 |
2009年 | 9559篇 |
2008年 | 10396篇 |
2007年 | 8533篇 |
2006年 | 7804篇 |
2005年 | 7079篇 |
2004年 | 6769篇 |
2003年 | 6180篇 |
2002年 | 5459篇 |
2001年 | 4472篇 |
2000年 | 3155篇 |
1999年 | 1861篇 |
1998年 | 1756篇 |
1997年 | 1653篇 |
1996年 | 1461篇 |
1995年 | 1205篇 |
1994年 | 1100篇 |
1993年 | 980篇 |
1992年 | 740篇 |
1991年 | 686篇 |
1990年 | 560篇 |
1989年 | 440篇 |
1988年 | 372篇 |
1987年 | 354篇 |
1986年 | 352篇 |
1985年 | 477篇 |
1984年 | 472篇 |
1983年 | 267篇 |
1982年 | 367篇 |
1981年 | 309篇 |
1980年 | 224篇 |
1979年 | 170篇 |
1978年 | 119篇 |
1977年 | 96篇 |
1976年 | 94篇 |
1975年 | 88篇 |
排序方式: 共有10000条查询结果,搜索用时 421 毫秒
1.
《Health & place》2022
PurposeAccording to the social determinants of health framework, income inequality is a potential risk factor for adverse mental health. However, few studies have explored the mechanisms suspected to mediate this relationship. The current study addresses this gap through a mediation analysis to determine if social support and community engagement act as mediators linking neighbourhood income inequality to maternal anxiety and depressive symptoms within a cohort of new mothers living in the City of Calgary, Canada.MethodsData collected at three years postpartum from mothers belonging to the All Our Families (AOF) cohort were used in the current study. Maternal data were collected between 2012 and 2015 and linked to neighbourhood socioeconomic data from the 2006 Canadian Census. Income inequality was measured using Gini coefficients derived from 2006 after-tax census data. Generalized structural equation models were used to quantify the associations between income inequality and mental health symptoms, and to assess the potential direct and indirect mediating effects of maternal social support and community engagement.ResultsIncome inequality was not significantly associated with higher depressive symptoms (β = 0.32, 95%CI = −0.067, 0.70), anxiety symptoms (β = 0.11, 95%CI = −0.39, 0.60), or lower social support. Income inequality was not associated with community engagement. For the depression models, higher social support was significantly associated with lower depressive symptoms (β = −0.13, 95%CI = −0.15, −0.097), while community engagement was not significantly associated with depressive symptoms (β = 0.059, 95%CI = −0.15, 0.27). Similarly, for the anxiety models, lower anxiety symptoms were significantly associated with higher levels of social support (β = −0.17, 95%CI = −0.20, −0.13) but not with higher levels of community engagement (β = 0.14, 95%CI = −0.14, 0.41).ConclusionThe current study did not find clear evidence for social support or community engagement mediating the relationship between neighbourhood income inequality and maternal mental health. Future investigations should employ a broader longitudinal approach to capture changes in income inequality, potential mediators, and mental health symptomatology over time. 相似文献
2.
3.
4.
5.
6.
《Cancer cell》2021,39(9):1214-1226.e10
- Download : Download high-res image (204KB)
- Download : Download full-size image
7.
Major depressive disorder and other neuropsychiatric disorders are often managed with long-term use of antidepressant medication. Fluoxetine, an SSRI antidepressant, is widely used as a first-line treatment for neuropsychiatric disorders. However, fluoxetine has also been shown to increase the risk of metabolic diseases such as non-alcoholic fatty liver disease. Fluoxetine has been shown to increase hepatic lipid accumulation in vivo and in vitro. In addition, fluoxetine has been shown to alter the production of prostaglandins which have also been implicated in the development of non-alcoholic fatty liver disease. The goal of this study was to assess the effect of fluoxetine exposure on the prostaglandin biosynthetic pathway and lipid accumulation in a hepatic cell line (H4-II-E-C3 cells). Fluoxetine treatment increased mRNA expression of prostaglandin biosynthetic enzymes (Ptgs1, Ptgs2, and Ptgds), PPAR gamma (Pparg), and PPAR gamma downstream targets involved in fatty acid uptake (Cd36, Fatp2, and Fatp5) as well as production of 15-deoxy-Δ12,14PGJ2 a PPAR gamma ligand. The effects of fluoxetine to induce lipid accumulation were attenuated with a PTGS1 specific inhibitor (SC-560), whereas inhibition of PTGS2 had no effect. Moreover, SC-560 attenuated 15-deoxy-Δ12,14PGJ2 production and expression of PPAR gamma downstream target genes. Taken together these results suggest that fluoxetine-induced lipid abnormalities appear to be mediated via PTGS1 and its downstream product 15d-PGJ2 and suggest a novel therapeutic target to prevent some of the adverse effects of fluoxetine treatment. 相似文献
8.
目的 探讨溶质载体蛋白(SLC)及其受体趋化因子受体7(CCR7)与I期非小细胞肺癌(NSCLC)淋巴结微转移的相关性。方法 选取2019年1月~2020年3月于我院就诊的I期NSCLC患者127例为研究对象,按照淋巴结微转移情况分为对照组92例和转移组35例,所有患者入院后均通过根治术切除病灶,通过免疫组化方式检测病灶中SLC7A11及CCR7含量,并收集患者临床资料、实验室检查资料及影像学检查资料。通过Logistic回归分析评价SLC7A11及CCR7与淋巴结微转移之间的关系。最后通过建立ROC曲线分析两者及其联合检测对NSCLC患者微淋巴结转移的预测价值。结果 两组患者SLC7A11及CCR7表达水平存在显著差异(P<0.05)。转移组患者病灶直径、支气管受累及TLG显著高于对照组(P<0.05)。病灶直径(OR=49.254,95%CI=11.062~507.604)是影响NSCLC淋巴结微转移的独立危险因素(P<0.05)。SLC7A11(OR=8.622)及CCR7(OR=8.709)表达水平是影响NSCLC淋巴结微转移的独立因素(P<0.05)。SLC7A11、CCR7及联合诊断对NSCLC淋巴结微转移具有较好的检测价值(均P<0.05)。联合检测特异度显著高于 SLC7A11及CCR7单独检测(2=7.292,15.125;均P<0.01)。结论 SLC家族的中SLC7A11及其受体CCR7与NSCLC患者微淋巴结转移显著相关。 相似文献
9.
《Value in health》2022,25(6):1010-1017
ObjectivesSurvival extrapolation for chimeric antigen receptor T-cell therapies is challenging, owing to their unique mechanistic properties that translate to complex hazard functions. Axicabtagene ciloleucel is indicated for the treatment of relapse or refractory diffuse large B-cell lymphoma after 2 or more lines of therapy based on the ZUMA-1 trial. Four data snapshots are available, with minimum follow-up of 12, 24, 36, and 48 months. This analysis explores how survival extrapolations for axicabtagene ciloleucel using ZUMA-1 data can be validated and compared.MethodsThree different parametric modeling approaches were applied: standard parametric, spline-based, and cure-based models. Models were compared using a range of metrics, across the 4 data snapshot, including visual fit, plausibility of long-term estimates, statistical goodness of fit, inspection of hazard plots, point-estimate accuracy, and conditional survival estimates.ResultsStandard and spline-based parametric extrapolations were generally incapable of fitting the ZUMA-1 data well. Cure-based models provided the best fit based on the earliest data snapshot, with extrapolations remaining consistent as data matured. At 48 months, the maximum survival overestimate was 8.3% (Gompertz mixture-cure model) versus the maximum underestimate of 33.5% (Weibull standard parametric model).ConclusionsWhere a plateau in the survival curve is clinically plausible, cure-based models may be helpful in making accurate predictions based on immature data. The ability to reliably extrapolate from maturing data may reduce delays in patient access to potentially lifesaving treatments. Additional research is required to understand how models compare in broader contexts, including different treatments and therapeutic areas. 相似文献
10.
Phoebe Hammer Kevin White Stephanie Mengden Vessy Korcheva Philipp W. Raess 《Journal of cutaneous pathology》2019,46(5):343-346
Cutaneous leiomyomas are rare benign smooth‐muscle tumors. These lesions are distinguished based on their cell of origin and are subclassified as pilar leiomyoma, angioleiomyoma, and genital‐type leiomyoma. Nipple leiomyoma is the least common genital‐type leiomyoma, arising from the dartoic muscle cell of the nipple. Histologic examination of the lesion is necessary for definitive diagnosis, and these uncommon tumors can pose a diagnostic challenge. We describe herein a series of six nipple leiomyomas with a spectrum of histologic appearances. 相似文献