全文获取类型
收费全文 | 6500篇 |
免费 | 458篇 |
国内免费 | 28篇 |
专业分类
耳鼻咽喉 | 184篇 |
儿科学 | 187篇 |
妇产科学 | 165篇 |
基础医学 | 812篇 |
口腔科学 | 172篇 |
临床医学 | 554篇 |
内科学 | 1475篇 |
皮肤病学 | 119篇 |
神经病学 | 316篇 |
特种医学 | 211篇 |
外国民族医学 | 1篇 |
外科学 | 986篇 |
综合类 | 160篇 |
一般理论 | 13篇 |
预防医学 | 390篇 |
眼科学 | 112篇 |
药学 | 582篇 |
1篇 | |
中国医学 | 43篇 |
肿瘤学 | 503篇 |
出版年
2023年 | 77篇 |
2022年 | 239篇 |
2021年 | 291篇 |
2020年 | 171篇 |
2019年 | 243篇 |
2018年 | 260篇 |
2017年 | 180篇 |
2016年 | 205篇 |
2015年 | 219篇 |
2014年 | 295篇 |
2013年 | 362篇 |
2012年 | 495篇 |
2011年 | 527篇 |
2010年 | 270篇 |
2009年 | 185篇 |
2008年 | 324篇 |
2007年 | 312篇 |
2006年 | 302篇 |
2005年 | 265篇 |
2004年 | 233篇 |
2003年 | 257篇 |
2002年 | 202篇 |
2001年 | 121篇 |
2000年 | 118篇 |
1999年 | 103篇 |
1998年 | 44篇 |
1997年 | 27篇 |
1996年 | 25篇 |
1995年 | 28篇 |
1994年 | 34篇 |
1993年 | 27篇 |
1992年 | 45篇 |
1991年 | 39篇 |
1990年 | 53篇 |
1989年 | 32篇 |
1988年 | 37篇 |
1987年 | 24篇 |
1986年 | 27篇 |
1985年 | 29篇 |
1984年 | 21篇 |
1983年 | 24篇 |
1982年 | 24篇 |
1979年 | 19篇 |
1978年 | 20篇 |
1977年 | 16篇 |
1976年 | 19篇 |
1975年 | 10篇 |
1974年 | 14篇 |
1973年 | 15篇 |
1972年 | 10篇 |
排序方式: 共有6986条查询结果,搜索用时 15 毫秒
71.
A retrospective review of all patients older than 35 who underwent elective single blastocyst transfer was performed. Twenty-three of the 45 patients (51.1%) have an ongoing pregnancy or liveborn delivery, with a mean age of 37.3 years, demonstrating a clear role for elective single transfer in this relatively older IVF population. 相似文献
72.
73.
74.
Iqra Jabbar Yasir Zaman Khaled Althubeiti Sattam Al Otaibi M. Zahid Ishaque Nasir Rahman Mohammad Sohail Alamzeb Khan Asad Ullah Tommaso Del Rosso Quaid Zaman Rajwali Khan Aurangzeb Khan 《RSC advances》2022,12(21):13456
The hydrothermal method was used to create dilute magnetic semiconductor nanoparticles of Zn1−xCoxO (x = 0, 0.01, 0.05, 0.09). The effect of cobalt doping on the microstructure, morphological and optical properties of Zn1−xCoxO was also studied and the Co doping to host ZnO was confirmed from XRD and EDX analysis. The structural analysis showed that doping of cobalt into ZnO decreased the crystallinity, but the preferred orientation didn''t change. SEM analysis revealed that the cobalt dopant did not have a strong influence on the shape of the synthesized nanoparticles. No defect-related absorption peaks were observed in the UV-Vis spectra. The crystallinity of the doped samples was improved by high growth temperature and long growth time. Ferromagnetic behavior above room temperature was detected in co-doped ZnO nanoparticles. The ferromagnetic behavior increased with increasing Co (up to x = 0.05) doping. The ferromagnetic behavior declined when the Co content was further increased. Related research shows that doped ZnO nanoparticles have better dielectric, electrical conductivity, and magnetic properties than pure ZnO. This high ferromagnetism is usually a response reported for dilute magnetic semiconductors. These semiconductor nanoparticles were further used to designed spintronic based applications.The enlarged central part M–H loop shows for the Co = 0.09 doped ZnO sample, the ferromagnetic (FM) behavior increased, i.e., a Mr of 0.2412 emu g−1 with a Hc of 85 Oe. 相似文献
75.
Antioxidant activity, free radical scavenging activity and phenolic content of red cabbage (Brassica oleracea var. capitata rubra), Chinese cabbage (Brassica rapa pekinensis var cylindrica), green cabbage (Brassica oleracea var capitata), mustard cabbage (Brassica juncea var rugosa) and Chinese white cabbage (Brassica rapa var chinensis), grown in Malaysia, were evaluated. Red cabbage had the highest antioxidant activity and phenolic content compared to the other cruciferous vegetables studied (p < 0.05). The contributions of all cruciferous vegetables to the antioxidant activity was >79%. The radical scavenging activity was in the order of Chinese white cabbage > red cabbage > mustard cabbage > Chinese cabbage > green cabbage. There was a significant difference (p < 0.05) in the means of scavenging activity observed between cabbage, Chinese cabbage and Chinese mustard. Phenolic content was significantly different (p < 0.05) among all the cruciferous vegetables studied, and was in the order of red cabbage > Chinese white cabbage > green cabbage > Chinese cabbage >mustard cabbage. The study indicated that red cabbage possessed the highest antioxidant capacity and phenolic compounds concentration among all the cruciferous vegetables studied. 相似文献
76.
Ramez A. Al-Mansob Herda Yati Katman Abdulnaser M. Al-Sabaeei Muhammad Zamzami Amin Al-Fakih Willy Kuay Wei Taha M. Jassam Jamal Alsharef Salihah B. Surol Nurul H. Yusof Suhana Koting 《Materials》2022,15(11)
This study aimed to evaluate the effects of carbon nanofibers (CNFs) on the performance of liquid epoxidized natural rubber (LENR)-modified asphalt. The physical, adhesion and rheological properties were determined by several tests such as penetration, elastic recovery, ring and ball softening point, Brookfield rotational viscometer, AFM and dynamic shear rheometer. LENR was used at concentrations of 3, 6, and 9%, while CNFs were used at contents of 0.3, 0.4, and 0.5% by weight of asphalt. Conventional test results showed that the increases in LENR and LENR/CNFs composite contents in binder leads to an increase in the hardness and consistency and a reduction in the temperature susceptibility of base asphalt. Adhesion results revealed that the addition of CNFs significantly increases the adhesion and bonding properties of base and rubberized binders. Rheological properties analysis exhibited that LENR improved the viscoelastic properties and permanent deformation resistance of asphalt at different temperatures and frequencies. On the other hand, it was found that the addition of CNFs significantly improves the stiffness, elasticity, and hardness of LENR-modified binders. The 6% LENR and 0.4% CNFs were found to be the optimum to enhance the physical, adhesion, and rheological properties of asphalt in this study. Thus, it can be stated that the addition of CNFs is promising to improve the performance of rubberized binders for high temperature applications. 相似文献
77.
Mahdi Asghari Ozma Amin Abbasi Sousan Akrami Masoud Lahouty Nayyer Shahbazi Khudaverdi Ganbarov Pasquale Pagliano Sahar Sabahi ükran Kse Mehdi Yousefi Sounkalo Dao Mohammad Asgharzadeh Hedayat Hosseini Hossein Samadi Kafil 《Le infezioni in medicina : rivista periodica di eziologia, epidemiologia, diagnostica, clinica e terapia delle patologie infettive》2022,30(2):180
78.
Simona Sacco Faisal Mohammad Amin Messoud Ashina Lars Bendtsen Christina I. Deligianni Raquel Gil-Gouveia Zaza Katsarava Antoinette MaassenVanDenBrink Paolo Martelletti Dimos-Dimitrios Mitsikostas Raffaele Ornello Uwe Reuter Margarita Sanchez-del-Rio Alexandra J. Sinclair Gisela Terwindt Derya Uluduz Jan Versijpt Christian Lampl 《The journal of headache and pain》2022,23(1)
BackgroundA previous European Headache Federation (EHF) guideline addressed the use of monoclonal antibodies targeting the calcitonin gene-related peptide (CGRP) pathway to prevent migraine. Since then, randomized controlled trials (RCTs) and real-world evidence have expanded the evidence and knowledge for those treatments. Therefore, the EHF panel decided to provide an updated guideline on the use of those treatments.MethodsThe guideline was developed following the Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) approach. The working group identified relevant questions, performed a systematic review and an analysis of the literature, assessed the quality of the available evidence, and wrote recommendations. Where the GRADE approach was not applicable, expert opinion was provided.ResultsWe found moderate to high quality of evidence to recommend eptinezumab, erenumab, fremanezumab, and galcanezumab in individuals with episodic and chronic migraine. For several important clinical questions, we found not enough evidence to provide evidence-based recommendations and guidance relied on experts’ opinion. Nevertheless, we provided updated suggestions regarding the long-term management of those treatments and their place with respect to the other migraine preventatives.ConclusionMonoclonal antibodies targeting the CGRP pathway are recommended for migraine prevention as they are effective and safe also in the long-term.Supplementary InformationThe online version contains supplementary material available at 10.1186/s10194-022-01431-x. 相似文献
79.
Nicole Frumento Alexis Figueroa Tingchang Wang Muhammad N. Zahid Shuyi Wang Guido Massaccesi Georgia Stavrakis James E. Crowe Jr Andrew I. Flyak Hongkai Ji Stuart C. Ray George M. Shaw Andrea L. Cox Justin R. Bailey 《The Journal of clinical investigation》2022,132(15)
A prophylactic hepatitis C virus (HCV) vaccine that elicits neutralizing antibodies could be key to HCV eradication. However, the genetic and antigenic properties of HCV envelope (E1E2) proteins capable of inducing anti-HCV broadly neutralizing antibodies (bNAbs) in humans have not been defined. Here, we investigated the development of bNAbs in longitudinal plasma of HCV-infected persons with persistent infection or spontaneous clearance of multiple reinfections. By measuring plasma antibody neutralization of a heterologous virus panel, we found that the breadth and potency of the antibody response increased upon exposure to multiple genetically distinct infections and with longer duration of viremia. Greater genetic divergence between infecting strains was not associated with enhanced neutralizing breadth. Rather, repeated exposure to antigenically related, antibody-sensitive E1E2s was associated with potent bNAb induction. These data reveal that a prime-boost vaccine strategy with genetically distinct, antibody-sensitive viruses is a promising approach to inducing potent bNAbs in humans. 相似文献
80.
Nur Najihah Izzati Mat Rani Xiang Yi Chen Zahraa M.Al-Zubaidi Hanisah Azhari Tzar Mohd Nizam Khaitir Pei Yuen Ng Fhataheya Buang Geok Chin Tan Yin Ping Wong Mazlina Mohd Said Adeel Masood Butt Azmy A.Hamid Mohd Cairul Iqbal Mohd Amin 《Asian Journal of Pharmaceutical Sciences》2022,17(1):102-119
This study focused on the encapsulation of vancomycin(VAN) into liposomes coated with a red blood cell membrane with a targeting ligand, daptomycin–polyethylene glycol–1,2-distearoyl-sn-glycero-3-phosphoethanolamine, formed by conjugation of DAPT and Nhydroxysuccinimidyl-polyethylene glycol-1,2-distearoyl-sn-glycero-3-phosphoethanolamine.This formulation is capable of providing controlled and targeted drug delivery to the bacterial cytoplasm. We performed MALDI-TOF, NMR and FTIR analyses to conf... 相似文献