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91.
Gruchala M Ciećwierz D Wasag B Targoński R Dubaniewicz W Nowak A Sobiczewski W Ochman K Romanowski P Limon J Rynkiewicz A 《American heart journal》2003,145(1):125-131
Background There is growing evidence from recent studies that atrial natriuretic peptide (ANP) plays an important part in coronary blood flow regulation and in atherosclerosis. Transition T2238→C in the atrial natriuretic peptide (ANP) precursor gene, which leads potentially to the translation of ANP with 2 additional arginines, has been suggested to be associated with salt-sensitive hypertension. According to our knowledge, this study is the first to look for the potential association of the ScaI ANP gene polymorphism with the history of nonfatal myocardial infarction and the extent of coronary artery disease (CAD).Methods The study was performed in 847 consecutive, white patients (719 men and 128 women) with significant coronary artery stenosis confirmed by means of elective coronary angiography (at least 1 coronary artery with ≥50% lumen narrowing). Screening for the T2238→C substitution was performed by means of polymerase chain reaction of genomic DNA, followed by ScaI digestion and agarose gel electrophoresis.Results We found a significant association of the A2A2 ScaI ANP genotype with a higher incidence of positive history of nonfatal myocardial infarction (odds ratio 1.85, 95% CI 1.33-2.58) and multiple-vessel CAD (odds ratio 1.45, 95% CI 1.02-2.06). The ScaI ANP genotype distribution did not differ with age, sex, body mass index, plasma lipids, hypertension, diabetes mellitus, and family history of CAD in studied groups.Conclusions Our results suggest that the ScaI ANP polymorphism may be associated with nonfatal myocardial infarction and the extent of CAD. However, the precise mechanism of this association remains to be determined. (Am Heart J 2003;145:125-31.) 相似文献
92.
Myśliwiec M Myśliwska J Zorena K Balcerska A Malinowska E Wiśniewski P 《Diabetes research and clinical practice》2008,82(1):108-112
The aim of the study was to assess the relationship between IL-6 gene polymorphism at -174(G>C) and the coincidence of celiac and autoimmune thyroid diseases with type 1 diabetes mellitus (DM1) in children. 200 children with DM1 aged 13.23+/-3.54 years and 172 healthy controls were analyzed. The IL-6 gene -174(G>C) polymorphism at the promoter region of the gene was analyzed by the PCR-RFLP method. The genotype distribution was significantly different in diabetic children as compared to the healthy controls (p=0.01). In DM1 patients GC heterozygotes were the most common (52.5%), while CC homozygotes accuted for 29% and GG homozygotes only for 18% of cases. In contrast, GG homozygotes were much more frequent among healthy children (31%). Besides, the GG homozygotes were significantly more frequent among diabetic children with celiac disease (p=0.04) in relation to those without autoimmune complications. In children with autoimmune thyroiditis, the distribution of the IL-6 genotypes was similar to that seen in diabetic patients without autoimmune complications (p=0.24). The results of our study suggest that the diabetic children, who have IL-6 gene -174GG genotype may have an increased risk for celiac disease development. 相似文献
93.
Jan Rykala Karolina Przybylowska Ireneusz Majsterek Grazyna Pasz-Walczak Andrzej Sygut Adam Dziki Piotr Kuna 《Archives of Medical Science》2015,11(3):619-627
Introduction
Fibroblast growth factor-2 (FGF2) is an important signalling molecule contributing to angiogenesis, tumour growth and progression and its expression is implicated in breast cancer (BC) development. We investigated whether –553 T/A FGF2 gene polymorphism is associated with the risk and progression of BC in Polish women.Material and methods
The –553 T/A polymorphism was genotyped in 230 breast cancer patients and 245 control subjects, using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) approach. Moreover, FastQuant human angiogenesis array was used to measure FGF2 levels in tumour (n = 127) and serum (n = 76) samples.Results
The T/A genotypes (OR = 2.12, 95% CI: 1.20–3.74) (p = 0.08) and the combined heterozygotes T/A and homozygote A/A (OR = 2.18, 95% CI: 1.24–3.83) (p = 0.006) had an increased risk of BC. The median FGF2 levels in the tumours of A allele carriers were significantly increased compared to T/T patients, whereas in serum FGF2 levels were hardly altered among different genotype carriers. Significantly higher frequency of A allele was found in patients with lymph node metastases (OR = 2.53; 95% CI: 1.23–5.17) (p = 0.009) and human epidermal growth factor receptor 2 positive tumour (OR = 3.22, 95% CI: 1.49–6.99) (p = 0.002). Furthermore, Kaplan-Meier survival analysis showed that the A allele predicted worse disease-free survival (DFS) in BC patients.Conclusions
Our study shows for the first time that the –553 T/A FGF2 gene polymorphism may be associated with a risk of BC developing and progression in Polish women and may have prognostic value for the assessment of BC high-risk groups. 相似文献94.
Piotr Kukla M.D. Ph.D. Adrian Baranchuk M.D. Ph.D. Marek Jastrzębski M.D. Ph.D. Leszek Bryniarski M.D. Ph.D. 《Annals of noninvasive electrocardiology》2014,19(6):601-603
A 72‐year‐old man with heart failure, left ventricular dysfunction (ejection fraction 20%), prior ischemic stroke, COPD, and exacerbation of chronic renal failure was admitted in our unit. Serum potassium was 6.1 mmol/L, calcium concentration was at the lower normal range 2.15 mmol/L, and NT‐pro‐BNP was 28,900 pg/mL. The surface 12‐lead electrocardiogram (ECG) showed sinus rhythm at 60 bpm, PR interval 160 ms, QRS duration 115 ms, QT interval 460 ms, and left ventricular hypertrophy criteria. Negative T waves in leads I, II, aVL, and V4–V6 were also seen. In leads V4–V6, negative U waves were observed in concordance with negative T waves. In all precordial leads, beat‐to‐beat U‐wave polarity variability was observed as a polarity variation from negative to positive with associated and stable negative T waves, in a beat‐to‐beat alternate morphology. 相似文献
95.
Burkert Pieske Carsten Tschpe Rudolf A. de Boer Alan G. Fraser Stefan D. Anker Erwan Donal Frank Edelmann Michael Fu Marco Guazzi Carolyn S.P. Lam Patrizio Lancellotti Vojtech Melenovsky Daniel A. Morris Eike Nagel Elisabeth Pieske-Kraigher Piotr Ponikowski Scott D. Solomon Ramachandran S. Vasan Frans H. Rutten Adriaan A. Voors Frank Ruschitzka Walter J. Paulus Petar Seferovic Gerasimos Filippatos 《European journal of heart failure》2020,22(3):391-412
Making a firm diagnosis of chronic heart failure with preserved ejection fraction (HFpEF) remains a challenge. We recommend a new stepwise diagnostic process, the ‘HFA–PEFF diagnostic algorithm’. Step 1 (P=Pre‐test assessment) is typically performed in the ambulatory setting and includes assessment for heart failure symptoms and signs, typical clinical demographics (obesity, hypertension, diabetes mellitus, elderly, atrial fibrillation), and diagnostic laboratory tests, electrocardiogram, and echocardiography. In the absence of overt non‐cardiac causes of breathlessness, HFpEF can be suspected if there is a normal left ventricular (LV) ejection fraction, no significant heart valve disease or cardiac ischaemia, and at least one typical risk factor. Elevated natriuretic peptides support, but normal levels do not exclude a diagnosis of HFpEF. The second step (E: Echocardiography and Natriuretic Peptide Score) requires comprehensive echocardiography and is typically performed by a cardiologist. Measures include mitral annular early diastolic velocity (e′), LV filling pressure estimated using E/e′, left atrial volume index, LV mass index, LV relative wall thickness, tricuspid regurgitation velocity, LV global longitudinal systolic strain, and serum natriuretic peptide levels. Major (2 points) and Minor (1 point) criteria were defined from these measures. A score ≥5 points implies definite HFpEF; ≤1 point makes HFpEF unlikely. An intermediate score (2–4 points) implies diagnostic uncertainty, in which case Step 3 (F1: Functional testing) is recommended with echocardiographic or invasive haemodynamic exercise stress tests. Step 4 (F2: Final aetiology) is recommended to establish a possible specific cause of HFpEF or alternative explanations. Further research is needed for a better classification of HFpEF. 相似文献
96.
John R. Teerlink Beth A. Davison Gad Cotter Aldo P. Maggioni Naoki Sato Ovidiu Chioncel Georg Ertl G. Michael Felker Gerasimos Filippatos Barry H. Greenberg Peter S. Pang Piotr Ponikowski Christopher Edwards Stefanie Senger Sam L. Teichman Olav Wendelboe Nielsen Adriaan A. Voors Marco Metra 《European journal of heart failure》2020,22(2):315-329
97.
Elbieta Szczepaska Anna Synak Piotr Bojarski Pawe Niedziakowski Anna Wciso Tadeusz Ossowski Beata Grobelna 《Materials》2020,13(22)
The present work describes synthesis, characterization, and use of a new dansyl-labelled Ag@SiO2 nanocomposite as an element of a new plasmonic platform to enhance the fluorescence intensity. Keeping in mind that typical surface plasmon resonance (SPR) characteristics of silver nanoparticles coincide well enough with the absorption of dansyl molecules, we used them to build the core of the nanocomposite. Moreover, we utilized 10 nm amino-functionalized silica shell as a separator between silver nanoparticles and the dansyl dye to prevent the dye-to-metal energy transfer. The dansyl group was incorporated into Ag@SiO2 core-shell nanostructures by the reaction of aminopropyltrimethoxysilane with dansyl chloride and we characterized the new dansyl-labelled Ag@SiO2 nanocomposite using transmission electron microscopy (TEM) and Fourier-transform infrared spectroscopy (FTIR). Additionally, water wettability measurements (WWM) were carried out to assess the hydrophobicity and hydrophilicity of the studied surface. We found that the nanocomposite deposited on a semitransparent silver mirror strongly increased the fluorescence intensity of dansyl dye (about 87-fold) compared with the control sample on the glass, proving that the system is a perfect candidate for a sensitive plasmonic platform. 相似文献
98.
99.
The paper presents the results of research concerning three fiber materials—mineral wool, hemp fiber and wood wool—as loose-fill thermal insulation materials. The analysis used the material parameters determined in previous works conducted by the authors, such as thermal conductivity and air permeability in relation to bulk density. These materials exhibit open porosity; thus, convection is an essential phenomenon in the heat transfer process. The paper aimed at conducting thermal simulations of various frame wall variants which were filled with the above-mentioned insulation materials. The simulations were performed with the Control Volume Method using the Delphin 5.8 software. The studies accounted for the effect of wind pressure and the time of its influence on a wall insulated by means of fiber material with a thickness of 150 as well as 250 mm. The simulation enabled us to obtain such data as maximal R-value reduction and time to return to equilibrium after filtration for the analyzed materials. The study proved that heat transfer in these insulations strongly depends on the bulk density, thickness of the insulation and wind pressure. The decrease in R is reduced as the density increases. This results from the decreased air permeability characterizing the material. Wind washing causes lower R reduction than air filtration in all models. The greater the thickness, the longer it takes for the models to return to the equilibrium state following air filtration (and wind washing). This period is comparable for air filtration and wind washing. Hemp fibers were characterized with the strongest susceptibility to air filtration; in the case of wood wool, it was also high, but lower than for hemp fibers, while mineral wool was characterized with the lowest. 相似文献
100.
Aptamers are short fragments of nucleic acids, DNA or RNA that have the ability to bind selected proteins with high specificity and affinity. These properties allow them to be used as an element of biosensors for the detection of specific proteins, including viral ones, which makes it possible to design valuable diagnostic tools. The influenza virus causes a huge number of human and animal deaths worldwide every year, and contributes to remarkable economic losses. In addition, in 2020, a new threat appeared—the SARS-Cov-2 pandemic. Both disease entities, especially in the initial stage of infection, are almost identical in terms of signs and symptoms. Therefore, a diagnostic solution is needed that will allow distinguishing between both pathogens, with high sensitivity and specificity; it should be cheap, quick and possible to use in the field, for example, in a doctor’s office. All the mentioned properties are met by aptasensors in which the detection elements are specific aptamers. We present here the latest developments in the construction of various types of aptasensors for the detection of influenza virus. Aptasensor operation is based on the measurement of changes in electric impedance, fluorescence or electric signal (impedimetric, fluorescence and electrochemical aptasensors, respectively); it allows both qualitative and quantitative determinations. The particularly high advancement for detecting of influenza virus concerns impedimetric aptasensors. 相似文献