全文获取类型
收费全文 | 6067篇 |
免费 | 391篇 |
国内免费 | 21篇 |
专业分类
耳鼻咽喉 | 39篇 |
儿科学 | 214篇 |
妇产科学 | 76篇 |
基础医学 | 950篇 |
口腔科学 | 154篇 |
临床医学 | 480篇 |
内科学 | 1130篇 |
皮肤病学 | 253篇 |
神经病学 | 860篇 |
特种医学 | 309篇 |
外科学 | 423篇 |
综合类 | 31篇 |
一般理论 | 1篇 |
预防医学 | 456篇 |
眼科学 | 134篇 |
药学 | 435篇 |
中国医学 | 13篇 |
肿瘤学 | 521篇 |
出版年
2024年 | 4篇 |
2023年 | 52篇 |
2022年 | 70篇 |
2021年 | 135篇 |
2020年 | 118篇 |
2019年 | 136篇 |
2018年 | 154篇 |
2017年 | 121篇 |
2016年 | 143篇 |
2015年 | 205篇 |
2014年 | 230篇 |
2013年 | 300篇 |
2012年 | 500篇 |
2011年 | 485篇 |
2010年 | 289篇 |
2009年 | 282篇 |
2008年 | 420篇 |
2007年 | 400篇 |
2006年 | 386篇 |
2005年 | 394篇 |
2004年 | 338篇 |
2003年 | 327篇 |
2002年 | 330篇 |
2001年 | 56篇 |
2000年 | 48篇 |
1999年 | 69篇 |
1998年 | 87篇 |
1997年 | 64篇 |
1996年 | 51篇 |
1995年 | 42篇 |
1994年 | 31篇 |
1993年 | 38篇 |
1992年 | 11篇 |
1991年 | 11篇 |
1990年 | 15篇 |
1989年 | 19篇 |
1988年 | 18篇 |
1987年 | 15篇 |
1986年 | 14篇 |
1985年 | 14篇 |
1984年 | 10篇 |
1983年 | 4篇 |
1982年 | 4篇 |
1981年 | 6篇 |
1980年 | 3篇 |
1979年 | 3篇 |
1978年 | 3篇 |
1977年 | 3篇 |
1974年 | 3篇 |
1968年 | 4篇 |
排序方式: 共有6479条查询结果,搜索用时 10 毫秒
101.
Although implantable glucose sensors have existed for over 30 years, their function deteriorates in hours to days, in large part as a result of tissue responses to the implanted sensor (i.e., acute and chronic inflammation, fibrosis, and vessel regression). Little is known about the mediators and mechanisms that control these tissue responses to implantable glucose sensors. In the present study, we developed and validated a murine model for implantable glucose sensors, which suitably parallel sensor function in humans. Using special care in implantation and implant retaining techniques, we demonstrated that (1) sensor function deteriorates rapidly within days post-implantation and (2) loss of glucose sensor function correlated with tissue reactions at the sites of sensor implantation, especially in the vicinity of the glucose oxidase-based working electrode. These studies establish a murine model that can be used to evaluate implantable glucose sensors in vivo. This model should provide the foundation for future studies to understand the factors and mechanisms that control sensor function in vivo. 相似文献
102.
103.
Ulrike Baranyi Martina Gattringer Andreas M. Farkas Karin Hock Nina Pilat John Iacomini Thomas Wekerle 《European journal of immunology》2013,43(9):2451-2460
The transplantation of allergens (e.g. Phl p 5 or Bet v 1) expressed on BM cells as membrane‐anchored full‐length proteins leads to permanent tolerance at the T‐cell, B‐cell, and effector‐cell levels. Since the exposure of complete allergens bears the risk of inducing anaphylaxis, we investigated here whether expression of Phl p 5 in the cytoplasm (rather than on the cell surface) is sufficient for tolerance induction. Transplantation of BALB/c BM retrovirally transduced to express Phl p 5 in the cytoplasm led to stable and durable molecular chimerism in syngeneic recipients (~20% chimerism at 6 months). Chimeras showed allergen‐specific T‐cell hyporesponsiveness. Further, Phl p 5‐specific TH1‐dependent humoral responses were tolerized in several chimeras. Surprisingly, Phl p 5‐specific IgE and IgG1 levels were significantly reduced but still detectable in sera of chimeric mice, indicating incomplete B‐cell tolerance. No Phl p 5‐specific sIgM developed in cytoplasmic chimeras, which is in marked contrast to mice transplanted with BM expressing membrane‐anchored Phl p 5. Thus, the expression site of the allergen substantially influences the degree and quality of tolerance achieved with molecular chimerism in IgE‐mediated allergy. 相似文献
104.
Ulrike Schliesser Martin Chopra Andreas Beilhack Christine Appelt Simone Vogel Julia Schumann Ivo Panov Katrin Vogt Stephan Schlickeiser Sven Olek Kathryn Wood Christine Brandt Hans‐Dieter Volk Birgit Sawitzki 《European journal of immunology》2013,43(12):3291-3305
The transfer of alloreactive regulatory T (aTreg) cells into transplant recipients represents an attractive treatment option to improve long‐term graft acceptance. We recently described a protocol for the generation of aTreg cells in mice using a nondepleting anti‐CD4 antibody (aCD4). Here, we investigated whether adding TGF‐β and retinoic acid (RA) or rapamycin (Rapa) can further improve aTreg‐cell generation and function. Murine CD4+ T cells were cultured with allogeneic B cells in the presence of aCD4 alone, aCD4+TGF‐β+RA or aCD4+Rapa. Addition of TGF‐β+RA or Rapa resulted in an increase of CD25+Foxp3+‐expressing T cells. Expression of CD40L and production of IFN‐γ and IL‐17 was abolished in aCD4+TGF‐β+RA aTreg cells. Additionally, aCD4+TGF‐β+RA aTreg cells showed the highest level of Helios and Neuropilin‐1 co‐expression. Although CD25+Foxp3+ cells from all culture conditions displayed complete demethylation of the Treg‐specific demethylated region, aCD4+TGF‐β+RA Treg cells showed the most stable Foxp3 expression upon restimulation. Consequently, aCD4+TGF‐β+RA aTreg cells suppressed effector T‐cell differentiation more effectively in comparison to aTreg cells harvested from all other cultures, and furthermore inhibited acute graft versus host disease and especially skin transplant rejection. Thus, addition of TGF‐β+RA seems to be superior over Rapa in stabilising the phenotype and functional capacity of aTreg cells. 相似文献
105.
William S. Helton Ulrike Ossowski Sanna Malinen 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2013,226(3):357-362
The present study was designed to explore the relationships between post-disaster self-reports of depression, vigilance task performance, and frontal cerebral oxygenation. Forty participants (20 women) performed vigilance tasks following a magnitude 7.1 earthquake in Christchurch, New Zealand. In addition to performance, we measured self-reports of depression, anxiety, and stress anchored to the initial earthquake event, and frontal cerebral activity with functional near-infrared spectroscopy. Among the participants, one case may have been an outlier with extremely elevated levels of self-reported depressivity. Excluding the extreme case, there was a correlation between change in response time (response slowing) and depressivity. Including the case there was a correlation between depressivity and right hemisphere oxygenation. These results provide some support for a relationship between moderate depressivity and sustained attention difficulties. 相似文献
106.
Niki Antypa Raffaella Calati Daniel Souery Silvia Pellegrini Othman Sentissi Daniela Amital Ulrike Moser Stuart Montgomery Siegfried Kasper Joseph Zohar Diana De Ronchi Julien Mendlewicz Alessandro Serretti 《Journal of affective disorders》2013
Background
Social adjustment is impaired in depressed patients. The difficulty to adjust to social circumstances has been hypothesized to be one of the causes of depression, as well as a consequence of the disorder. Genetic variation in the serotonin transporter gene has been previously associated with social adjustment levels in patients with mood disorders.Methods
We investigated whether variations on the HTR1A (rs6295) and HTR2A (rs7997012) genes were associated with levels of social adjustment using the Social Adjustment Scale in two samples of depressed patients (total n=156).Results
Patients carrying the GG genotype of the HTR2A-rs7997012 showed better social adjustment in areas of work and family unit bonding.Limitations
These findings did not survive correction for multiple testing and should be interpreted with caution.Conclusion
Our finding is in line with previous observations that have associated the G allele of the HTR2A-rs7997012 with higher rate of antidepressant response. The HTR2A-rs7997012 is worthy of further investigation in studies examining factors that are related to depression course and outcome. 相似文献107.
PTSD can develop in the aftermath of traumatic incidents like combat, sexual abuse, or life threatening accidents. Unfortunately, there are still no biomarkers for this debilitating anxiety disorder in clinical use. Anyhow, there are numerous studies describing potential PTSD biomarkers, some of which might progress to the point of practical use in the future. Here, we outline and comment on some of the most prominent findings on potential imaging, psychological, endocrine, and molecular PTSD biomarkers and classify them into risk, disease, and therapy markers. Since for most of these potential PTSD markers a causal role in PTSD has been demonstrated or at least postulated, this review also gives an overview on the current state of research on PTSD pathobiology. 相似文献
108.
Alexander Seiler Annemarie Brandhofe Ren-Maxime Gracien Waltraud Pfeilschifter Elke Hattingen Ralf Deichmann Ulrike Nth Marlies Wagner 《Journal of cerebral blood flow and metabolism》2021,41(1):67
Leptomeningeal collateral supply is considered pivotal in steno-occlusive vasculopathy to prevent chronic microstructural ischaemic tissue damage. The aim of this study was to assess the alleged protective role of leptomeningeal collaterals in patients with unilateral high-grade steno-occlusive vasculopathy using quantitative (q)T2 mapping and perfusion-weighted imaging (PWI)-based collateral abundance. High-resolution qT2 was used to estimate microstructural damage of the segmented normal-appearing cortex. Volumetric abundance of collaterals was assessed based on PWI source data. The ratio relative cerebral blood flow/relative cerebral blood volume (rCBF/rCBV) as a surrogate of relative cerebral perfusion pressure (rCPP) was used to investigate the intravascular hemodynamic competency of pial collateral vessels and the hemodynamic state of brain parenchyma. Within the dependent vascular territory with increased cortical qT2 values (P = 0.0001) compared to the contralateral side, parenchymal rCPP was decreased (P = 0.0001) and correlated negatively with increase of qT2 (P < 0.05). Furthermore, volumetric abundance of adjacent leptomeningeal collaterals was significantly increased (P < 0.01) and negatively correlated with changes of parenchymal rCPP (P = 0.01). Microstructural cortical damage is closely related to restrictions of antegrade blood flow despite increased pial collateral vessel abundance. Therefore, increased leptomeningeal collateral supply cannot necessarily be regarded as a sign of effective compensation in patients with high-grade steno-occlusive vasculopathy. 相似文献
109.
110.
Der Freie Zahnarzt - 相似文献