全文获取类型
收费全文 | 2765篇 |
免费 | 201篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 21篇 |
儿科学 | 94篇 |
妇产科学 | 50篇 |
基础医学 | 508篇 |
口腔科学 | 36篇 |
临床医学 | 377篇 |
内科学 | 554篇 |
皮肤病学 | 39篇 |
神经病学 | 275篇 |
特种医学 | 58篇 |
外科学 | 299篇 |
综合类 | 10篇 |
预防医学 | 268篇 |
眼科学 | 48篇 |
药学 | 169篇 |
中国医学 | 2篇 |
肿瘤学 | 171篇 |
出版年
2024年 | 6篇 |
2023年 | 27篇 |
2022年 | 32篇 |
2021年 | 78篇 |
2020年 | 62篇 |
2019年 | 77篇 |
2018年 | 80篇 |
2017年 | 53篇 |
2016年 | 80篇 |
2015年 | 74篇 |
2014年 | 85篇 |
2013年 | 152篇 |
2012年 | 213篇 |
2011年 | 237篇 |
2010年 | 108篇 |
2009年 | 117篇 |
2008年 | 165篇 |
2007年 | 180篇 |
2006年 | 163篇 |
2005年 | 148篇 |
2004年 | 153篇 |
2003年 | 158篇 |
2002年 | 154篇 |
2001年 | 15篇 |
2000年 | 18篇 |
1999年 | 20篇 |
1998年 | 32篇 |
1997年 | 22篇 |
1996年 | 14篇 |
1995年 | 24篇 |
1994年 | 11篇 |
1993年 | 7篇 |
1992年 | 8篇 |
1989年 | 5篇 |
1988年 | 9篇 |
1987年 | 6篇 |
1985年 | 6篇 |
1984年 | 5篇 |
1983年 | 6篇 |
1982年 | 11篇 |
1981年 | 7篇 |
1980年 | 6篇 |
1978年 | 10篇 |
1975年 | 10篇 |
1974年 | 7篇 |
1938年 | 5篇 |
1937年 | 7篇 |
1935年 | 5篇 |
1931年 | 7篇 |
1928年 | 7篇 |
排序方式: 共有2979条查询结果,搜索用时 62 毫秒
61.
Susan Mikkelsen Khoa Manh Dinh Jens Kjrgaard Boldsen Ole Birger Pedersen Gitte Juel Holst Mikkel Steen Petersen Kathrine Agergrd Kaspersen Bjarne Kuno Mller Kaspar Rene Nielsen Helene Martina Paarup Klaus Rostgaard Henrik Hjalgrim Erik Srensen Linda Jenny Handgaard Thomas Folkmann Hansen Karina Banasik Kristoffer Slvsten Burgdorf Henrik Ullum Torben Sigsgaard Christian Erikstrup 《Clinical and translational allergy》2021,11(1)
BackgroundAllergic rhinitis (AR), allergic conjunctivitis (AC), and asthma composing multiple phenotypes and improved understanding of these phenotypes and their respective risk factors are needed.ObjectivesThe objective of this study was to define the prevalence of AR, AC, and asthma and their association with allergen‐specific immunoglobulin E (sIgE) sensitization in a large cohort of blood donors and identify risk factors.MethodsFrom the nationwide population‐based Danish Blood Donor Study, 52,976 participants completed an electronic questionnaire including AR, AC, asthma, allergic predisposition, and childhood residence. Of these, 25,257 were additionally tested for sIgE to inhalation allergens (Phadiatop).ResultsThe prevalence of sIgE sensitization, AR, AC, and asthma was 30%, 19%, 15%, and 9%, respectively. The youngest birth cohorts had the highest prevalence of sIgE sensitization and symptoms of asthma, AR, and AC, and for asthma, they apparently experienced symptoms at an earlier age. The sIgE sensitization was positively associated with male sex. The sIgE seroprevalence was higher in participants with both AR and AC (ARC) than in participants with either AR or AC. Allergic predisposition and sIgE sensitization increased the risk of the diseases, while farm upbringing was associated with reduced prevalence of ARC, however, only in sIgE sensitized participants.ConclusionBirth year, childhood residence, sIgE sensitization, and allergic predisposition were associated with asthma, AR, and AC prevalence. Individuals with self‐reported ARC represent a primarily sIgE‐positive phenotype, while those with either AR or AC represent more diverse phenotypes. 相似文献
62.
Abrahamsson Helene Eriksson Lars Abrahamsson Peter Häggman-Henrikson Birgitta 《Clinical oral investigations》2020,24(1):61-70
Clinical Oral Investigations - To evaluate the effectiveness of surgical and nonsurgical treatment of temporomandibular joint (TMJ) luxation. This systematic literature review searched PubMed, the... 相似文献
63.
Patrick P. Torreiter Susanne Macher Eva-Maria Matzhold Bernhard Resch Philipp Klaritsch Günther F. Krmczi Helene Polin Leopold Neuhold Marlies Schnbacher Peter Schlenke Thomas Wagner 《Transfusion medicine and hemotherapy : offizielles Organ der Deutschen Gesellschaft fur Transfusionsmedizin und Immunhamatologie》2021,48(3):183
BackgroundThe development of allo-anti-Rh17 (anti-Hr0) in a −D– phenotype whose red blood cells (RBCs) lack CcEe antigens is most likely triggered by transfusion, transplantation, or pregnancy. Gene conversion is the predominating factor in generating RHD-CE-D and RHCE-D-CE hybrids like −D–.MethodsWe report here immunohematological and obstetrical data from 2 of the 5 pregnancies of a 24-year-old woman presenting with the −D– phenotype with anti-Rh17. Blood group typing, antibody screening, antibody differentiation, direct antiglobulin test (DAT), and antibody titers were performed by routine gel technology and tube testing. Additionally, molecular genetic analysis was performed. Fetal surveillance was done by sonographic evaluation of the fetal middle cerebral artery peak systolic velocity (MCA-PSV).ResultsBlood group typing showed O, C-c-D+E-e- and the DAT was negative. DNA sequencing revealed homozygosity for an RHCE-D(3–9)-CE null allele. Anti-Rh17 titers in the fourth pregnancy remained between 1:8 and 1:128, and no signs for a fetal anemia were observed. However, in the fifth pregnancy, the antibody titers increased up to 1:4,096. Signs of moderate fetal anemia were detected and cesarean section was performed at 34 + 6 weeks of gestation. The newborn presented with hemolytic anemia (cord blood hemoglobin [Hb] = 8.5 mg/dL). She received 2 compatible (small) packed RBC concentrates, phototherapy, and intravenous immunoglobulins.ConclusionOur case shows that the risk for hemolytic complications increases with the number of pregnancies of sensitized women. Only people who also lack CcEe antigens are compatible as donors. The role of such rare donors as lifesavers, their freedom, and voluntariness conflict with the urgent need for compatible blood. 相似文献
64.
65.
66.
67.
In Vitro Assembly of Neurospora Assimilatory Nitrate Reductase from Protein Subunits of a Neurospora Mutant and the Xanthine Oxidizing or Aldehyde Oxidase Systems of Higher Animals 总被引:17,自引:3,他引:17
下载免费PDF全文
![点击此处可从《Proceedings of the National Academy of Sciences of the United States of America》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Paul A. Ketchum Helene Y. Cambier William A. Frazier III Charles H. Madansky Alvin Nason 《Proceedings of the National Academy of Sciences of the United States of America》1970,66(3):1016-1023
In vitro assembly or complementation of a hybrid assimilatory nitrate reductase was attained by mixing a preparation of nitrate-induced N. crassa mutant nit-1 specifically with acid-treated (pH 2.5) bovine milk or intestinal xanthine oxidase, rabbit liver aldehyde oxidase, or chicken liver xanthine dehydrogenase. The complementation reaction specifically required induced nit-1, the only nitrate reductase mutant of Neurospora that lacked xanthine dehydrogenase and was unable to use hypoxathine or nitrate as a sole nitrogen source. The complementing activities of the above acid-treated enzymes correspond to their xanthine or aldehyde oxidizing activity profiles on sucrose density gradients. The resulting soluble, reduced nicotinamide adenine dinucleotide phosphate (NADPH)-nitrate reductases are the same as the Neurospora wild type enzyme in sucrose density gradient profile, molecular weight, substrate affinities, and sensitivity to inhibitors and temperature. By analogy to a similar in vitro complementation of nitrate reductase in mixtures of induced nit-1 and individual nonalleic Neurospora mutants, or uninduced wild type, the complemented nitrate apparently consists of an inducible protein subunit (possessing inducible NADPH-cytochrome c reductase) furnished by nit-1 and a subunit from the acid-treated xanthine or aldehyde oxidizing system which can substitute for the constitutive component furnished by the other mutants or uninduced wild type. The data suggest that Neurospora nitrate reductase and the xanthine oxidizing system and aldehyde oxidase of animals, all of which are molybdenum-containing enzymes catalyzing the reduction of nitrate to nitrite, share a highly similar protein subunit. 相似文献
68.
Severely elevated C‐reactive protein accompanied by prolonged high fever and leukocytosis in a healthy peripheral blood stem cell donor: an atypical granulocyte–colony‐stimulating factor reaction?
下载免费PDF全文
![点击此处可从《Transfusion》网站下载免费的PDF全文](/ch/ext_images/free.gif)
69.
70.
Heiko Sic Helene Kraus Josef Madl Karl-Andreas Flittner Audrey Lilly von Münchow Kathrin Pieper Marta Rizzi Anne-Kathrin Kienzler Korcan Ayata Sebastian Rauer Burkhard Kleuser Ulrich Salzer Meike Burger Katja Zirlik Vassilios Lougaris Alessandro Plebani Winfried Römer Christoph Loeffler Samantha Scaramuzza Anna Villa Emiko Noguchi Bodo Grimbacher Hermann Eibel 《The Journal of allergy and clinical immunology》2014