全文获取类型
收费全文 | 22257篇 |
免费 | 1376篇 |
国内免费 | 109篇 |
专业分类
耳鼻咽喉 | 284篇 |
儿科学 | 500篇 |
妇产科学 | 469篇 |
基础医学 | 2794篇 |
口腔科学 | 679篇 |
临床医学 | 1885篇 |
内科学 | 5660篇 |
皮肤病学 | 480篇 |
神经病学 | 1895篇 |
特种医学 | 527篇 |
外科学 | 3553篇 |
综合类 | 145篇 |
一般理论 | 9篇 |
预防医学 | 1400篇 |
眼科学 | 630篇 |
药学 | 1219篇 |
1篇 | |
中国医学 | 50篇 |
肿瘤学 | 1562篇 |
出版年
2023年 | 159篇 |
2022年 | 339篇 |
2021年 | 757篇 |
2020年 | 389篇 |
2019年 | 665篇 |
2018年 | 813篇 |
2017年 | 472篇 |
2016年 | 526篇 |
2015年 | 657篇 |
2014年 | 892篇 |
2013年 | 1110篇 |
2012年 | 1807篇 |
2011年 | 1869篇 |
2010年 | 985篇 |
2009年 | 911篇 |
2008年 | 1491篇 |
2007年 | 1537篇 |
2006年 | 1405篇 |
2005年 | 1276篇 |
2004年 | 1097篇 |
2003年 | 944篇 |
2002年 | 857篇 |
2001年 | 174篇 |
2000年 | 160篇 |
1999年 | 201篇 |
1998年 | 198篇 |
1997年 | 144篇 |
1996年 | 143篇 |
1995年 | 140篇 |
1994年 | 125篇 |
1993年 | 122篇 |
1992年 | 112篇 |
1991年 | 100篇 |
1990年 | 73篇 |
1989年 | 82篇 |
1988年 | 74篇 |
1987年 | 69篇 |
1986年 | 78篇 |
1985年 | 58篇 |
1984年 | 72篇 |
1983年 | 63篇 |
1982年 | 66篇 |
1981年 | 67篇 |
1980年 | 48篇 |
1979年 | 43篇 |
1978年 | 38篇 |
1977年 | 36篇 |
1976年 | 33篇 |
1974年 | 25篇 |
1973年 | 29篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Jose Javier Ashwini Hinge James Bartram Juying Xu Marie-Dominique Filippi 《Haematologica》2022,107(6):1323
Bone marrow failure syndromes are characterized by ineffective hematopoiesis due to impaired fitness of hematopoietic stem cells. They can be acquired during bone marrow stress or innate and are associated with driver genetic mutations. Patients with a bone marrow failure syndrome are at higher risk of developing secondary neoplasms, including myelodysplastic syndromes and leukemia. Despite the identification of genetic driver mutations, the hematopoietic presentation of the disease is quite heterogeneous, raising the possibility that non-genetic factors contribute to the pathogenesis of the disease. The role of inflammation has emerged as an important contributing factor, but remains to be understood in detail. In this study, we examined the effect of increased transforming growth factor-b (TGFb) signaling, in combination or not with an acute innate immune challenge using polyinosinc:polycytidilic acid (pIC), on the hematopoietic system without genetic mutations. We show that acute rounds of pIC alone drive a benign age-related myeloid cell expansion and increased TGFb signaling alone causes a modest anemia in old mice. In sharp contrast, increased TGFb signaling plus acute pIC challenge result in chronic pancytopenia, expanded hematopoietic stem and progenitor cell pools, and increased bone marrow dysplasia 3-4 months after stress, which are phenotypes similar to human bone marrow failure syndromes. Mechanistically, this disease phenotype is uniquely associated with increased mitochondrial content, increased reactive oxygen species and enhanced caspase-1 activity. Our results suggest that chronic increased TGFb signaling modifies the memory of an acute immune response to drive bone marrow failure without the need for a preexisting genetic insult. Hence, non-genetic factors in combination are sufficient to drive bone marrow failure. 相似文献
92.
Michael Puckette Victoria Primavera Erica Martel Jose Barrera William Hurtle Benjamin Clark Barbara Kamicker Mariceny Zurita David Brake John Neilan 《Viruses》2022,14(5)
RNA viruses, such as foot-and-mouth disease virus (FMDV), have error-prone replication resulting in the continuous emergence of new viral strains capable of evading current vaccine coverage. Vaccine formulations must be regularly updated, which is both costly and technically challenging for many vaccine platforms. In this report, we describe a plasmid-based virus-like particle (VLP) production platform utilizing transiently transfected mammalian cell cultures that combines both the rapid response adaptability of nucleic-acid-based vaccines with the ability to produce intact capsid epitopes required for immunity. Formulated vaccines which employed this platform conferred complete protection from clinical foot-and-mouth disease in both swine and cattle. This novel platform can be quickly adapted to new viral strains and serotypes through targeted exchanges of only the FMDV capsid polypeptide nucleic acid sequences, from which processed structural capsid proteins are derived. This platform obviates the need for high biocontainment manufacturing facilities to produce inactivated whole-virus vaccines from infected mammalian cell cultures, which requires upstream expansion and downstream concentration of large quantities of live virulent viruses. 相似文献
93.
Identification
of RAD51–BRCA2 Inhibitors Using N-Acylhydrazone-Based
Dynamic Combinatorial Chemistry
Greta Bagnolini Beatrice Balboni Fabrizio Schipani Dario Gioia Marina Veronesi Francesca De Franco Cansu Kaya Ravindra P. Jumde Jose Antonio Ortega Stefania Girotto Anna K. H. Hirsch Marinella Roberti Andrea Cavalli 《ACS medicinal chemistry letters》2022,13(8):1262
RAD51 is an ATP-dependent recombinase, recruited by BRCA2 to mediate DNA double-strand breaks repair through homologous recombination and represents an attractive cancer drug target. Herein, we applied for the first-time protein-templated dynamic combinatorial chemistry on RAD51 as a hit identification strategy. Upon design of N-acylhydrazone-based dynamic combinatorial libraries, RAD51 showed a clear templating effect, amplifying 19 N-acylhydrazones. Screening against the RAD51–BRCA2 protein–protein interaction via ELISA assay afforded 10 inhibitors in the micromolar range. Further 19F NMR experiments revealed that 7 could bind RAD51 and be displaced by BRC4, suggesting an interaction in the same binding pocket of BRCA2. These results proved not only that ptDCC could be successfully applied on full-length oligomeric RAD51, but also that it could address the need of alternative strategies toward the identification of small-molecule PPI inhibitors. 相似文献
94.
95.
96.
ngel Gimnez-Richarte Mabel Ortiz de Salazar Cristina Arbona María P. Gimnez-Richarte Miriam Collado Pedro L. Fernndez Francisco Quiles Carlos Clavijo Pascual Marco Jose-Manuel Ramos-Rincon 《Trasfusione del sangue》2022,20(4):267
BackgroundBlood transfusion centres should understand the epidemiology of emerging diseases that are transmissible through the transfusion of blood components. The risk of transmission of arboviruses through this route has become apparent in recent years. The aim of our study is to summarise the reported prevalence (viraemic rate, seroprevalence and/or antigen detection) of Chikungunya (CHIKV), Dengue (DENV) and Zika (ZIKV) viruses in blood donors according to screening test used and world region.Materials and methodsWe conducted a systematic literature review and meta-analysis having searched for information in the main bibliographic databases (MEDLINE, Embase, and Scopus). The prevalence for each of the viruses was calculated according to the screening test used and geographic location.ResultsWe included 18 records on CHIKV, 71 on DENV, and 27 on ZIKV. The highest prevalences of RNA for CHIKV were 1.9% in Puerto Rico (2014), 1.0% in Thailand (2009), and 1.0% in French Polynesia (2014–15). The highest prevalences of RNA for DENV were 5.5% in Saudi Arabia (2015–16), 2.3% in Madeira, Portugal (2012–13), and 0.6% in Brazil (2012). The highest prevalences of RNA for ZIKV were 2.8% in French Polynesia (2013–14), 2.7% in Brazil (2015–16), and 1.8% in Martinique (2016). Overall seroprevalence, as assessed by IgG antibodies, was 21.6% for CHIKV, 24.0% for DENV, and 5.1% for ZIKV.DiscussionOur study shows a high proportion of donors who are viraemic and asymptomatic, especially during outbreaks, with prevalences surpassing 5% for DENV, 1% for CHIKV, and 2% for ZIKV. These data confirm a clear threat to blood transfusion safety. The elevated seroprevalence for these three arboviruses is also indicative of their wide circulation in populations, correlating with an increased risk of infected but asymptomatic donors. Health centres and institutions must address this threat, especially in tropical regions where the biggest outbreaks occur. 相似文献
97.
Jose Maria Gomez-Arguelles Oscar Caceres Manuel Blanco Ceferino Maestu Francisco Martin 《Reumatologia》2022,60(3):209
IntroductionThere is growing interest in the relationship between fibromyalgia and processes related to food, such as food intolerances. In fact, different associations have been described between the control of dietary habits and the improvement of the different symptoms of fibromyalgia.Material and methodsWe collected the results of applying a specific test of histamine release related to the diet of patients with fibromyalgia, and evaluated the changes in terms of the symptoms usually described by the patients. A total of 84 patients who met the established criteria were recruited; 40 of them underwent the exclusion diet for a period of 6 months, while the remaining ones continued with their usual dietary habits. All patients were instructed not to modify any other parameter during the study, such as medication, exercise, or other complementary treatments. The parameters studied were as follows: the Fibromyalgia Impact Questionnaire (FIQ), the Gastrointestinal Symptoms Rating Scale (GSRS), the pain Visual Analogue Scale (VAS), as well as the patients’ body weight was controlled.ResultsThere was a significant improvement (p < 0.05) in the group of patients who underwent the exclusion diet in assesment by GSRS and in total in total body weight. There were no differences compared to the rest of the patients in terms of VAS and FIQ.ConclusionsDiet modification in patients with fibromyalgia by specific histamine relase test improves certain clinical parameters related to the symptoms of the digestive sphere, compared to the control group. Our work opens a possible way of non-pharmacological treatment to improve some symptoms of this very prevalent disease. 相似文献
98.
Deoxynivalenol (DON) remains one of the most concerning mycotoxins produced by the Fusarium genus due to the wide occurrence in highly consumed cereal-based food and its associated toxicological effects. Previous studies conducted in Spain and other European countries suggested that some vulnerable groups such as children could be exceeding the tolerable daily intakes. Thus, the aim of this study was to conduct a comprehensive and updated dietary exposure assessment study in Spain, with a specific analysis in the region of Catalonia. Cereal-based food samples collected during 2019 were analysed using liquid chromatography coupled to tandem mass spectrometry for multi-mycotoxin detection including DON and its main metabolites and derivatives. Consumption data were gathered from the nation-wide food surveys ENALIA and ENALIA2 conducted in Spain, and a specific survey conducted in Catalonia. The data were combined using deterministic and semi-parametric probabilistic methods. The results showed that DON was widely present in cereal-based food highly consumed in Spain and the Catalonia region. Exposure to DON among the adult population was globally low; however, among infants aged 3–9 years, it resulted in the median of 192 ng/kg body weight/day and the 95th percentiles of 604 ng/kg body weight/day, that would exceed the most conservative safety threshold for infants. Bread and pasta were the main contributing foodstuffs to the global exposure to DON, even among infants; thus, those foods should be considered a priority for food control or to develop strategies to reduce the exposure. In any case, further toxicological and epidemiological studies are required in order to refine the safety thresholds accounting for the sensitivity of the infant population. 相似文献
99.
Prada Diddier Baccarelli Andrea A. Terry Mary Beth Valdéz Leonora Cabrera Paula Just Allan Kloog Itai Caro Haydee García-Cuellar Claudia Sánchez-Pérez Yesennia Cruz Rodrigo Diaz-Chávez Jose Cortés Carlo Pérez Delia Meneses-García Abelardo Cantú-de-León David Herrera Luis A. Bargalló Enrique 《Breast cancer research and treatment》2021,187(2):525-533
Breast Cancer Research and Treatment - Many patients seek breast reconstruction following mastectomy. Debate exists regarding the best reconstructive option. The authors evaluate outcomes comparing... 相似文献
100.