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31.
Vainshtein Inna Roskos Lorin K. Cheng Jackie Sleeman Matthew A. Wang Bing Liang Meina 《Pharmaceutical research》2015,32(1):286-299
Pharmaceutical Research - Measurement of internalization of biopharmaceuticals targeting cell surface proteins can greatly facilitate drug development. The objective of this study was to develop a... 相似文献
32.
33.
Philippe Généreux Nicolo Piazza Maria C. Alu Tamim Nazif Rebecca T. Hahn Philippe Pibarot Jeroen J. Bax Jonathon A. Leipsic Philipp Blanke Eugene H. Blackstone Matthew T. Finn Samir Kapadia Axel Linke Michael J. Mack Raj Makkar Roxana Mehran Jeffrey J. Popma Martin B. Leon 《Journal of the American College of Cardiology》2021,77(21):2717-2746
34.
Amir Ahmadi Jonathon Leipsic Kristian A. Øvrehus Sara Gaur Emilia Bagiella Brian Ko Damini Dey Gina LaRocca Jesper M. Jensen Hans Erik Bøtker Stephan Achenbach Bernard De Bruyne Bjarne L. Nørgaard Jagat Narula 《JACC: Cardiovascular Imaging》2018,11(4):521-530
Objectives
The aims of the present study were: 1) to investigate the contribution of the extent of luminal stenosis and other lesion composition-related factors in predicting invasive fractional flow reserve (FFR); and 2) to explore the distribution of various combinations of morphological characteristics and the severity of stenosis among lesions demonstrating normal and abnormal FFR.Background
In patients with stable ischemic heart disease, FFR-guided revascularization, as compared with medical therapy alone, is reported to improve outcomes. Because morphological characteristics are the basis of plaque rupture and acute coronary events, a relationship between FFR and lesion characteristics may exist.Methods
This is a subanalysis of NXT (HeartFlowNXT: HeartFlow Analysis of Coronary Blood Flow Using Coronary CT Angiography), a prospective, multicenter study of 254 patients (age 64 ± 10 years, 64% male) with suspected stable ischemic heart disease; coronary computed tomography angiography including plaque morphology assessment, invasive angiography, and FFR were obtained for 383 lesions. Ischemia was defined by invasive FFR ≤0.80. Computed tomography angiography–defined morphological characteristics of plaques and their vascular location were used in univariate and multivariate analyses to examine their predictive value for invasive FFR. The distribution of various combinations of plaque morphological characteristics and the severity of stenosis among lesions demonstrating normal and abnormal FFR were examined.Results
The percentage of luminal stenosis, low-attenuation plaque (LAP) or necrotic core volume, left anterior descending coronary artery territory, and the presence of multiple lesions per vessel were the predictors of FFR. When grouped on the basis of degree of luminal stenosis, FFR-negative lesions had consistently smaller LAP volumes compared with FFR-positive lesions. The distribution of plaque characteristics in lesions with normal and abnormal FFR demonstrated that whereas FFR-negative lesions excluded likelihood of stenotic plaques with moderate to high LAP volumes, only one-third of FFR-positive lesions demonstrated obstructive plaques with moderate to high LAP volumes.Conclusions
In addition to the severity of luminal stenosis, necrotic core volume is an independent predictor of FFR. The distribution of plaque characteristics among lesions with varying luminal stenosis and normal and abnormal FFR may explain the outcomes associated with FFR-guided therapy. 相似文献35.
Summary There are important differences between the short- and long-term effects of adrenaline on determinants of glucose tolerance.
To assess this metabolic adaptation at tissue level, the present study examined the effect of acute and prolonged in vivo
elevation of adrenaline on glycogen metabolism and glycolysis in skeletal muscle. Adrenaline (50 ng · kg−1 · min−1) was infused for 2 h or 74 h and the results compared with 1 h 0.9% NaCl infusion in six trained dogs. Muscle glycogen content
was reduced by long-term adrenaline (161 ± 17 vs NaCl 250 ± 24 μmol/g dry weight;p < 0.05) but not short-term adrenaline (233 ± 21) indicating a sustained effect of adrenaline on glycogen metabolism. Acutely,
glycogen synthase I was reduced (short-term adrenaline 12 ± 6 vs NaC122 ± 7μmol glycosyl units · g−1 · min−1;p < 0.05) but returned to normal with prolonged adrenaline infusion (20 ± 5). In contrast, Km for glycogen phosphorylasea was not changed acutely (short-term adrenaline 31 ± 6 vs NaCl 27 ± 7 mmol/1 inorganic phosphate) but was reduced during long-term
infusion (19 ± 4;p < 0.05 vs short-term adrenaline). Thus, with short- and long-term adrenaline infusion, there were different enzyme changes,
although likely to promote glycogenolysis in both cases. In the glycolytic pathway the substrates glucose 6-phosphate and
fructose 6-phosphate did not change significantly and hexokinase was not inhibited. Acutely, phosphofructokinase had reduced
Vmax (short-term adrenaline 34 ± 6 vs NaCl 44 ± 5 U/g; p < 0.05) but was still above the maximal operating rate in vivo. With
prolonged adrenaline infusion, the Km for phosphofructokinase was reduced (long-term adrenaline 0.32 ± 0.03 vs NaCl 0.44 ± 0.07 mmol/l fructose 6-phosphate;p < 0.05). In this situation of relatively low glycolytic flux, the sustained glycogenolytic effect of prolonged adrenaline
infusion mediated by increased glycogen phosphorylase a ctivity occurs without a significant accumulation of hexose monophosphates
or impairment of glycolysis. 相似文献
36.
Andrew D. Choi Dustin M. Thomas James Lee Suhny Abbara Ricardo C. Cury Jonathon A. Leipsic Christopher Maroules Prashant Nagpal Michael L. Steigner Dee Dee Wang Michelle C. Williams Irfan Zeb Todd C. Villines Ron Blankstein 《Journal of Cardiovascular Computed Tomography》2021,15(1):2-15
Cardiovascular computed tomography (CCT) is a well-validated non-invasive imaging tool with an ever-expanding array of applications beyond the assessment of coronary artery disease. These include the evaluation of structural heart diseases, congenital heart diseases, peri-procedural electrophysiology applications, and the functional evaluation of ischemia. This breadth requires a robust and diverse training curriculum to ensure graduates of CCT training programs meet minimum competency standards for independent CCT interpretation. This statement from the Society of Cardiovascular Computed Tomography aims to supplement existing societal training guidelines by providing a curriculum and competency framework to inform the development of a comprehensive, integrated training experience for cardiology and radiology trainees in CCT. 相似文献
37.
Todd C. Villines Subhi J. Al’Aref Daniele Andreini Marcus Y. Chen Andrew D. Choi Carlo N. De Cecco Damini Dey James P. Earls Maros Ferencik Heidi Gransar Harvey Hecht Jonathon A. Leipsic Michael T. Lu Mohamed Marwan Pál Maurovich-Horvat Edward Nicol Gianluca Pontone Jonathan Weir-McCall Gudrun M. Feuchtner 《Journal of Cardiovascular Computed Tomography》2021,15(2):180-189
38.
Minkwan Kim Seung-Pyo Lee Soongu Kwak Seokhun Yang Yong-Jin Kim Daniele Andreini Mouaz H. Al-Mallah Matthew J. Budoff Filippo Cademartiri Kavitha Chinnaiyan Jung Hyun Choi Edoardo Conte Hugo Marques Pedro de Araújo Gonçalves Ilan Gottlieb Martin Hadamitzky Jonathon A. Leipsic Erica Maffei Hyuk-Jae Chang 《Journal of Cardiovascular Computed Tomography》2021,15(3):232-239
BackgroundThe association of age with coronary plaque dynamics is not well characterized by coronary computed tomography angiography (CCTA).MethodsFrom a multinational registry of patients who underwent serial CCTA, 1153 subjects (61 ± 5 years old, 61.1% male) were analyzed. Annualized volume changes of total, fibrous, fibrofatty, necrotic core, and dense calcification plaque components of the whole heart were compared by age quartile groups. Clinical events, a composite of all-cause death, acute coronary syndrome, and any revascularization after 30 days of the initial CCTA, were also analyzed. Random forest analysis was used to define the relative importance of age on plaque progression.ResultsWith a 3.3-years’ median interval between the two CCTA, the median annual volume changes of total plaque in each age quartile group was 7.8, 10.5, 10.8, and 12.1 mm3/year and for dense calcification, 2.5, 4.6, 5.4, and 7.1 mm3/year, both of which demonstrated a tendency to increase by age (p-for-trend = 0.001 and < 0.001, respectively). However, this tendency was not observed in any other plaque components. The annual volume changes of total plaque and dense calcification were also significantly different in the propensity score-matched lowest age quartile group versus the other age groups as was the composite clinical event (log-rank p = 0.003). In random forest analysis, age had comparable importance in the total plaque volume progression as other traditional factors.ConclusionsThe rate of whole-heart plaque progression and dense calcification increases depending on age. Age is a significant factor in plaque growth, the importance of which is comparable to other traditional risk factors.Clinical trial registrationURL: http://www.clinicaltrials.gov. Unique identifiers: NCT02803411. 相似文献
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40.
Vasvi Singh Andrew D. Choi Jonathon Leipsic Ayaz Aghayev James P. Earls Philipp Blanke Michael Steigner Leslee J. Shaw Phd Marcelo F. Di Carli Todd C. Villines Ron Blankstein 《Journal of Cardiovascular Computed Tomography》2021,15(1):16-26
The COVID-19 pandemic has affected patient care deliver throughout the world, resulting in a greater emphasis on efficiently and safety. In this article, we discuss the experiences of several North American centers in utilizing cardiac CT during the pandemic. We also provide a case-based overview which highlights the advantages of cardiac CT in evaluating the following scenarios: (1) patients with possible myocardial injury versus myocardial infarction; (2) patients with acute chest pain; (3) patients with stable chest pain; (4) patients with possible intracardiac thrombus; (5) patients with valvular heart disease. For each scenario, we also provide an overview of various societies recommendations which have highlighted the use of cardiac CT during different phases of the COVID-19 pandemic. We hope that the advantages of cardiac CT that have been realized during the pandemic can help promote wider adoption of this technique and improved coverage and payment by payors. 相似文献