全文获取类型
收费全文 | 4842篇 |
免费 | 344篇 |
国内免费 | 26篇 |
专业分类
耳鼻咽喉 | 21篇 |
儿科学 | 84篇 |
妇产科学 | 135篇 |
基础医学 | 989篇 |
口腔科学 | 42篇 |
临床医学 | 420篇 |
内科学 | 1088篇 |
皮肤病学 | 51篇 |
神经病学 | 582篇 |
特种医学 | 114篇 |
外科学 | 503篇 |
综合类 | 15篇 |
一般理论 | 2篇 |
预防医学 | 297篇 |
眼科学 | 100篇 |
药学 | 381篇 |
中国医学 | 8篇 |
肿瘤学 | 380篇 |
出版年
2024年 | 3篇 |
2023年 | 62篇 |
2022年 | 162篇 |
2021年 | 220篇 |
2020年 | 99篇 |
2019年 | 142篇 |
2018年 | 163篇 |
2017年 | 97篇 |
2016年 | 129篇 |
2015年 | 158篇 |
2014年 | 186篇 |
2013年 | 227篇 |
2012年 | 364篇 |
2011年 | 422篇 |
2010年 | 238篇 |
2009年 | 219篇 |
2008年 | 367篇 |
2007年 | 362篇 |
2006年 | 345篇 |
2005年 | 288篇 |
2004年 | 259篇 |
2003年 | 247篇 |
2002年 | 208篇 |
2001年 | 30篇 |
2000年 | 14篇 |
1999年 | 28篇 |
1998年 | 36篇 |
1997年 | 33篇 |
1996年 | 19篇 |
1995年 | 19篇 |
1994年 | 6篇 |
1993年 | 10篇 |
1992年 | 7篇 |
1991年 | 6篇 |
1990年 | 2篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1986年 | 3篇 |
1984年 | 4篇 |
1983年 | 3篇 |
1982年 | 3篇 |
1981年 | 3篇 |
1980年 | 3篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1974年 | 3篇 |
1972年 | 1篇 |
1969年 | 1篇 |
1968年 | 1篇 |
1964年 | 1篇 |
排序方式: 共有5212条查询结果,搜索用时 15 毫秒
41.
The role of IL‐5 in chronic spontaneous urticarial (CSU) is unclear. It may be that benralizumab is an important bidirectional modifier of CSU; that is, blocking IL‐5 may improve CSU in some patients, but it is possible that it may worsen CSU in others. 相似文献
42.
Itay Bar-Or Victoria Indenbaum Merav Weil Michal Elul Nofar Levi Irina Aguvaev Zvi Cohen Virginia Levy Roberto Azar Batya Mannasse Rachel Shirazi Efrat Bucris Orna Mor Alin Sela Brown Danit Sofer Neta S. Zuckerman Ella Mendelson Oran Erster 《Viruses》2022,14(6)
In this report, we describe a national-scale monitoring of the SARS-CoV-2 (SC-2) variant dynamics in Israel, using multiple-time sampling of 13 wastewater treatment plants. We used a combination of inclusive and selective quantitative PCR assays that specifically identify variants A19/A20 or B.1.1.7 and tested each sample for the presence and relative viral RNA load of each variant. We show that between December 2020 and March 2021, a complete shift in the SC-2 variant circulation was observed, where the B.1.1.7 replaced the A19 in all examined test points. We further show that the normalized viral load (NVL) values and the average new cases per week reached a peak in January 2021 and then decreased gradually in almost all test points, in parallel with the progression of the national vaccination campaign, during February–March 2021. This study demonstrates the importance of monitoring SC-2 variant by using a combination of inclusive and selective PCR tests on a national scale through wastewater sampling, which is far more amendable for high-throughput monitoring compared with sequencing. This approach may be useful for real-time dynamics surveillance of current and future variants, such as the Omicron (BA.1, BA.2) and other variants. 相似文献
43.
Yamada Shinichi Takahashi Shun Malchow Berend Papazova Irina Stöcklein Sophia Ertl-Wagner Birgit Papazov Boris Kumpf Ulrike Wobrock Thomas Keller-Varady Katriona Hasan Alkomiet Falkai Peter Wagner Elias Raabe Florian J. Keeser Daniel 《European archives of psychiatry and clinical neuroscience》2022,272(6):957-969
European Archives of Psychiatry and Clinical Neuroscience - Significant evidence links white matter (WM) microstructural abnormalities to cognitive impairment in schizophrenia (SZ), but the... 相似文献
44.
Tatiana Safronova Andrey Kiselev Irina Selezneva Tatiana Shatalova Yulia Lukina Yaroslav Filippov Otabek Toshev Snezhana Tikhonova Olga Antonova Alexander Knotko 《Materials》2022,15(9)
Ceramic samples based on β-calcium pyrophosphate β-Ca2P2O7 were prepared from powders of γ-calcium pyrophosphate γ-Ca2P2O7 with preset molar ratios Ca/P = 1, 0.975 and 0.95 using firing at 900, 1000, and 1100 °C. Calcium lactate pentahydrate Ca(C3H5O3)2⋅5H2O and monocalcium phosphate monohydrate Ca(H2PO4)2⋅H2O were treated in an aqua medium in mechanical activation conditions to prepare powder mixtures with preset molar ratios Ca/P containing calcium hydrophosphates with Ca/P = 1 (precursors of calcium pyrophosphate Ca2P2O7). These powder mixtures containing calcium hydrophosphates with Ca/P = 1 and non-reacted starting salts were heat-treated at 600 °C after drying and disaggregation in acetone. Phase composition of all powder mixtures after heat treatment at 600 °C was presented by γ-calcium pyrophosphate γ-Ca2P2O7 according to the XRD data. The addition of more excess of monocalcium phosphate monohydrate Ca(H2PO4)2·H2O (with appropriate molar ratio of Ca/P = 1) to the mixture of starting components resulted in lower dimensions of γ-calcium pyrophosphate (γ-Ca2P2O7) individual particles. The grain size of ceramics increased both with the growth in firing temperature and with decreasing molar ratio Ca/P of powder mixtures. Calcium polyphosphate (t melt = 984 °C), formed from monocalcium phosphate monohydrate Ca(H2PO4)2⋅H2O, acted similar to a liquid phase sintering additive. It was confirmed by tests in vitro that prepared ceramic materials with preset molar ratios Ca/P = 1, 0.975, and 0.95 and phase composition presented by β-calcium pyrophosphate β-Ca2P2O7 were biocompatible and could maintain bone cells proliferation. 相似文献
45.
Karim Ravilevich Muratov Timur Rizovich Ablyaz Evgeny Anatolevich Gashev Irina Georgievna Goryacheva 《Materials》2022,15(9)
The regularities of the formation of the resulting raster tool trajectories based on Lissajous figures for the lapping process of planes are established. This makes it possible to maximize the cutting ability of the tool, which contributes to its more uniform wear and increased productivity and processing quality. Optimal parameters of productivity and roughness of the treated surface during lapping of zirconium ceramics are achieved through the use of ASM paste 28/20 µm. Based on Preston’s hypothesis, an exponential dependence of the change in the contact area during the lapping of planes of different initial shape of the macrorelief is obtained. The obtained theoretical and practical results of the study of the process of flat lapping with constant and variable clamping force of the treated surface to the surface of the tool. The influence of the force factor on the formation of the surface in the process of abrasive lapping has been established. Studies have been carried out and the main technological recommendations of precision surface treatment of workpieces based on hard, brittle ceramic material and bronze samples on equipment with a raster trajectory of the tool movement are presented. The optimal pressure value when processing ceramics should be considered 203–270 kPa (2.1–2.8 kg/cm2). 相似文献
46.
Zlatislav Stoyanov Lyoubka Decheva Irina Pashalieva Piareta Nikolova 《Central European Journal of Medicine》2012,7(1):1-8
The principle of symmetry-asymmetry is widely presented in the structural and functional organization of the nonliving and living nature. One of the most complex manifestations of this principle is the left-right asymmetry of the human brain. The present review summarizes previous and contemporary literary data regarding the role of brain asymmetry in neuroimmunomodulation. Some handedness-related peculiarities are outlined additionally. Brain asymmetry is considered to be imprinted in the formation and regulation of the individual’s responses and relationships at an immunological level with the external and internal environment. The assumptions that the hemispheres modulate immune response in an asymmetric manner have been confirmed in experiments on animals. Some authors assume that the right hemisphere plays an indirect role in neuroimmunomodulation, controlling and suppressing the left hemispheric inductive signals. 相似文献
47.
Janie J. Taylor Irina Kolobova Angela L. Lamson Natalia Sira David Musick 《Journal of health care chaplaincy》2013,19(3):91-107
Hospital chaplaincy and spiritual care services are important to patients’ medical care and well-being; however, little is known about healthcare providers’ experiences receiving spiritual support. A phenomenological study examined the shared experience of spiritual care between hospital chaplains and hospital-based healthcare providers (HBHPs). Six distinct themes emerged from the in-depth interviews: Awareness of chaplain availability, chaplains focus on building relationships with providers and staff, chaplains are integrated in varying degrees on certain hospital units, chaplains meet providers’ personal and professional needs, providers appreciate chaplains, and barriers to expanding hospital chaplains’ services. While HBHPs appreciated the care received and were able to provide better patient care as a result, participants reported that administrators may not recognize the true value of the care provided. Implications from this study are applied to hospital chaplaincy clinical, research, and training opportunities. 相似文献
48.
Aim: This paper explored the relationship between maternal controlling feeding behaviours and child eating and weight in preschool‐aged children. Methods: Ninety mothers of 2‐ to 5‐year‐old children (M = 3.48, SD = 0.84, 54.4% males) completed self‐report measures assessing maternal controlling feeding behaviours, child eating patterns and weight. Results: Univariate analyses indicated that child food neophobia was associated with authoritarian feeding (r= 0.29), pressure to eat (r= 0.28) and restriction (r= 0.34). Child food pickiness was associated with authoritarian feeding (r= 0.35). No association was found between maternal feeding strategies and child weight. Multivariate regression analyses indicated that authoritarian feeding, restriction and pressure to eat were significantly associated with the variance in child food neophobia (adjusted R2= 12.6%) and pickiness (adjusted R2= 12.0%). Conclusions: The findings suggest that maternal control in feeding is associated with undesirable eating patterns in preschool‐aged children. Interventions targeting reduction in maternal controlling feeding may promote desirable eating patterns in preschool‐aged children. 相似文献
49.
Autism is a complex neurodevelopmental disorder characterized by impairment in social interaction accompanied by a delay or lack of language, restricted interests, stereotyped behavior, and repetitive movement. Genetic predisposition to autism is evident from family and twin studies, and heritability in idiopathic autism is estimated at over 90%. Frequency of the disorder is approximately 1:2000 with a male to female ratio of 4:1. Affected individuals look normal at birth, and the symptoms manifest at the first 2-3 years of life. The spectrum of clinical symptoms and the severity of the disorder are variable even among siblings. Family studies and several genome-wide linkage analyses support the hypothesis of complex inheritance with involvement of as many as 10-100 genes of moderate effect. Identification of genes responsible for the phenotype would help to understand the molecular mechanisms of the disorder. Several genes have been proposed to play a role in susceptibility to autism, and this paper will overview those genes and their potential role in the disorder. 相似文献
50.
目的 探讨控制营养状态(CONUT)评分对人表皮生长因子受体2(HER2)阳性早期乳腺癌患者复发转移中的预测价值。方法 将2012年1月至2020年10月于新疆医科大学附属肿瘤医院行手术切除并接受曲妥珠单抗治疗的154例HER2阳性早期乳腺癌患者为研究对象进行回顾性分析。基于患者术前血清白蛋白、总胆固醇水平及外周血淋巴细胞计数,计算CONUT评分。通过受试者操作特征曲线(ROC曲线)对CONUT评分截止点进行分类:高CONUT与低CONUT组。组间基线特征分布的比较采用卡方χ2检验或Fisher确切概率法。绘制Kaplan-Meier曲线,并通过单因素和多因素Cox回归分析确定CONUT评分与乳腺癌患者复发转移的关系。结果 ROC曲线表明CONUT评分预测乳腺癌患者术后复发转移的最佳截止点为2.5,曲线下面积(AUC)为0.689 (95%CI=0.577~0.801)。基于此截止点,将所有患者分为高CONUT组(≥3分)与低CONUT组(<3分)。Kaplan-Meier曲线展示两组患者的5年无复发生存(RFS)率分别为69.7%和86.9%,差异具有统计学意义(χ2=8.00... 相似文献