全文获取类型
收费全文 | 5594篇 |
免费 | 366篇 |
国内免费 | 21篇 |
专业分类
耳鼻咽喉 | 68篇 |
儿科学 | 113篇 |
妇产科学 | 45篇 |
基础医学 | 719篇 |
口腔科学 | 110篇 |
临床医学 | 594篇 |
内科学 | 1288篇 |
皮肤病学 | 135篇 |
神经病学 | 432篇 |
特种医学 | 363篇 |
外科学 | 829篇 |
综合类 | 27篇 |
一般理论 | 5篇 |
预防医学 | 348篇 |
眼科学 | 210篇 |
药学 | 351篇 |
中国医学 | 5篇 |
肿瘤学 | 339篇 |
出版年
2023年 | 41篇 |
2022年 | 85篇 |
2021年 | 144篇 |
2020年 | 84篇 |
2019年 | 138篇 |
2018年 | 174篇 |
2017年 | 131篇 |
2016年 | 159篇 |
2015年 | 195篇 |
2014年 | 222篇 |
2013年 | 316篇 |
2012年 | 423篇 |
2011年 | 451篇 |
2010年 | 260篇 |
2009年 | 227篇 |
2008年 | 329篇 |
2007年 | 340篇 |
2006年 | 354篇 |
2005年 | 309篇 |
2004年 | 264篇 |
2003年 | 289篇 |
2002年 | 237篇 |
2001年 | 78篇 |
2000年 | 73篇 |
1999年 | 57篇 |
1998年 | 48篇 |
1997年 | 38篇 |
1996年 | 26篇 |
1995年 | 23篇 |
1994年 | 22篇 |
1993年 | 15篇 |
1992年 | 36篇 |
1991年 | 42篇 |
1990年 | 30篇 |
1989年 | 24篇 |
1988年 | 32篇 |
1987年 | 23篇 |
1986年 | 15篇 |
1985年 | 18篇 |
1984年 | 20篇 |
1983年 | 19篇 |
1981年 | 10篇 |
1979年 | 10篇 |
1978年 | 9篇 |
1977年 | 9篇 |
1975年 | 8篇 |
1974年 | 16篇 |
1973年 | 10篇 |
1972年 | 13篇 |
1970年 | 9篇 |
排序方式: 共有5981条查询结果,搜索用时 15 毫秒
1.
R. H. Wiesner B. J. Steffen K. M. David A. H. Chu R. D. Gordon J. R. Lake 《American journal of transplantation》2006,6(7):1609-1616
Mycophenolate mofetil (MMF) used in a triple-drug regimen has been shown to decrease acute rejection rates, compared to a double-drug regimen. The impact of MMF on late acute rejection (LAR) episodes has not been well described. To investigate the risk of LAR (rejection > or = 6 months post-transplantation) data from the Scientific Registry of Transplant Recipients (SRTR) were used. We studied adult primary liver transplant recipients transplanted between June 1, 1995, and April 30, 2004, with hepatitis C virus (HCV) (n = 3356), hepatitis B virus (HBV) (n = 550) or a nonviral (n = 5740) primary cause of liver disease who were recorded as receiving continuous 3-(MMF + Tacro + steroids) versus 2-drug (Tacro + steroids) therapy for at least 6 months immediately post transplantation. Kaplan-Meier analysis showed significantly lower LAR rates 4 years post-transplant in 3- versus 2-drug HCV, HBV and nonviral disease patients. Multivariate regression confirmed 3- versus 2-drug therapy to be associated with a decreased risk of LAR. Late graft survival was significantly lower at 4 years post-transplant for patients with LAR 6-12 months post-transplantation versus patients with early rejection (78.0% vs. 87.0%, p < 0.001) and no rejection (88.1%, p < 0.001). Three-drug versus 2-drug therapy for a minimum of 6 months may offer a better treatment strategy to avoid the consequences and expense of LAR episodes. 相似文献
2.
Priv.-Doz. Dr. Rüdiger Dissmann Joachim Schröder MD PhD Prof. Dr. med. Heinz Völler Prof. Dr. med. Steffen Behrens 《Clinical research in cardiology》2006,95(4):241-243
Summary During pacemaker implantation in a patient with permanent atrial fibrillation, it remained impossible to advance a passive
fixation lead with fins through the right atrium. However, a lead with a retractable screw easily passed the right atrium
and was positioned in the right ventricle. Transesophageal echocardiography revealed an extensive net–like perforated Eustachian
valve within the right atrium that had caused entrapment of the anchor fins during lead implantation. Remnants of embryonal
structures within the right atrium should be considered a rare possible barrier during pacemaker implantation. 相似文献
3.
Quantification of Basal and Stimulated ROS Levels as Predictors of Islet Potency and Function 总被引:2,自引:0,他引:2
B. Armann M. S. Hanson E. Hatch A. Steffen L. A. Fernandez 《American journal of transplantation》2007,7(1):38-47
We have developed a luminol-based assay using intact islets, which allows for quantification of reactive oxygen species (ROS). In addition, an index capable of characterizing metabolic and mitochondrial integrity prior to transplantation was created based on the capacity of islets to respond to high glucose and rotenone (mitochondrial respiratory chain complex I inhibitor) by production of ROS. To validate this assay, lipid peroxidation and antioxidative defense capacity were evaluated by detection of malondialdehyde (MDA) levels and glutathione peroxidase activity (GPx), respectively. Also, flow cytometric analyses of ROS (dihydroethidine), apoptosis (Annexin V, active caspases), necrosis (Topro3), and mitochondrial membrane potential (JC-1) were done in parallel to correlate with changes in luminol-measured ROS. ATP/ADP ratios were quantified by HPLC and the predictive value of ROS measurement on islet functional potency was correlated with capacity to reverse diabetes in a streptozotocin-induced diabetic NOD.scid mouse model as well as in human transplant recipients. Our data demonstrate that levels of ROS in islets correlate with the percentage of apoptotic cells and their functional potency in vivo. The ROS indices following glucose and rotenone exposure are indicative of metabolic potency and mitochondrial integrity and can be used as surrogate markers to evaluate the quality of islets prior to transplantation. 相似文献
4.
Frank G. Holz Caren Bellmann Heimo Steffen Bernhard Nölle Jens Huober Hermann Krastel Evangelos Alexandridis 《Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft》1997,94(5):337-342
Fragestellung: Die Karzinomassoziierte Retinopathie (CAR) stellt ein seltenes paraneoplastisches Syndrom dar, das bislang
am h?ufigsten bei kleinzelligen Bronchialkarzinomen beschrieben wurde. Wir berichten über 3 Patientinnen mit CAR in Gegenwart
eines Mammakarzinoms bzw. eines Karzinoids der Cervix uteri.
Patienten und Methode: Es wurden biomikroskopische, perimetrische, angiographische und elektrophysiologische Befunde erhoben.
Au?erdem erfolgte eine Testung der Immunreaktivit?t der Seren an humaner Retina.
Ergebnisse: Die Befunde umfa?ten ringf?rmige Gesichtsfelddefekte mit statokinetischer Dissoziation und eine pathologische
St?bchen- und Zapfenantwort im ERG. Bei 1 Patientin wurde immunhistochemisch eine Reaktion im Bereich der Photorezeptorinnensegmente,
der ?u?eren K?rnerschicht sowie der ?u?eren plexiformen Schicht bei fehlendem Nachweis von Antik?rpern gegen Recoverin gefunden.
Diskussion: Neben dem kleinzelligen Bronchialkarzinom k?nnen auch andere Prim?rtumoren mit einer CAR vergesellschaftet sein.
Der Nachweis von retinalen Autoantik?rpern unterstützt die Annahme einer tumorinduzierten Immunantwort aufgrund der Expression
identischer Epitope durch die Tumorzellen. Dabei kommen offensichtlich verschiedene retinale Proteine als Autoantigene in
Betracht.
相似文献
5.
Liver transplantation in HBsAg positive patients 总被引:1,自引:0,他引:1
G Blumhardt P Neuhaus W O Bechstein R Steffen U Hopf B M?ller R Raakow H Keck 《Transplantation proceedings》1990,22(4):1517-1518
6.
In CDH ultrasound control of reduction in the unstable period of the first 3 months has to be performed by an inguinal access, as the splint can not be removed for the reason of high risks of redislocation. Controls are possible whenever required, according to anglo-american techniques. Thus treatment within the first year of life may be controlled by ultrasound imaging alone. Criteria for detection of posterior and cranial redislocation as well as for the anterior positioning of the femoral head are given. 相似文献
7.
Boerhaave’s syndrome: Primary repair vs. esophageal resection—Case reports and meta-analysis of the literature 总被引:3,自引:0,他引:3
Otto Kollmar M.D. Werner Lindemann M.D. Sven Richter M.D. Ingo Steffen M.D. Georg Pistorius M.D. Martin K. Schilling M.D. 《Journal of gastrointestinal surgery》2003,7(6):726-734
Boerhaave’s syndrome is a life-threatening disease with a high mortality. With regard to the heterogeneity of treatment strategies,
no comparative studies exist and recommendations remain controversial. Seventeen cases of Boerhaave’s syndrome operated on
between 1989 and 2000 at our hospital were reviewed retrospectively to compare the time period between perforation and diagnosis,
and the morbidity and mortality among the different treatment options. In addition, we conducted a meta-analysis of the literature
including all series containing five or more patients and compared the findings with our own data. Our patients with a perforation
history of less than 12 hours showed significantly fewer signs of sepsis compared to patients with a history of more than
12 hours. In a comparison of patients with primary repair vs. patients treated with esophageal resection or an exclusion operation,
no differences were found. In the literature, patients with a long period of perforation (more than 24 hours) were treated
more often with an esophageal resection than patients with primary repair. In cases of Boerhaave’s syndrome, primary suturing
of the esophageal perforation should be reserved only for those patients presenting within 12 hours after perforation. In
all other cases, depending on the extent of the tissue damage, a two-stage esophageal resection with cervical esophagostomy
and gastrostomy is recommended as the safest treatment. 相似文献
8.
Martin Døssing Steffen Groth Jørgen Vestbo Ole Lyngenbo 《International archives of occupational and environmental health》1990,62(3):209-212
Summary Among 701 Copenhagen plumbers we examined the lung function of 23 never smokers, who had removed asbestos insulation and intermittently been exposed to high levels of asbestos for about 25 years without being exposed to welding fume. The plumbers had significantly lower TLC, MEF25, MEF50, closing volume and closing capacity in comparison to 23 never smoking electricians without asbestos exposure. There was no reduction in TLCO. Pulmonary clearance of aerosolized 99mTc-DTPA was normal indicating that the asbestos had not induced increases in pulmonary epithelial permeability. However, in 11 of the 23 plumbers the 99m-Tc-DTPA ventilation scintigrams had a slightly irregular and spotty appearance, which together with the results of the lung function tests are suggestive of small airways' dysfunction. None of the subjects had symptoms or clinical signs of lung disease. 相似文献
9.
Steffen Rickes Peter Rauh Daniel Ensberg Christine Uhle und Frank Aedtner 《Medizinische Klinik》2007,102(9):778-780
Ohne Zusammenfassung 相似文献
10.