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81.
Analysis of correlation between tuberculosis (TB) and human leukocyte antigen (HLA) in populations from Asia and Latin America has shown conflicting results. The aim of this study was to evaluate the frequency of HLA-DRB1-DQB1 two-locus haplotypes of 61 TB patients and 125 healthy volunteers in the same ethnic group in Poland. DRB1 and DQB1 alleles were determined by PCR-SSP "low-resolution" and "high-resolution" methods. Our study showed that DRB1*1601 and DQB1*0502 alleles were more frequent, whereas DQB1*0201 was rarer in TB than in controls. DRB1*16-DQB1*05, DRB1*04-DQB1*03 and DRB1*1601-DQB1*0502 haplotype were more common, and DRB1*11-DQB1*03 less frequent in TB in comparison to controls. Positive linkage disequilibrium (LD) for DRB1*01-DQB1*05, DRB1*03-DQB1*02, DRB1*11-DQB1*03, DRB1*13-DQB1*06 and DRB1*15-DQB1*06 was found in controls. A trend towards the positive LD for DRB1*01-DQB1*05, DRB1*03-DQB1*02, DRB1*11-DQB1*03, DRB1*15-DQB1*06 and DRB1*16-DQB1*05 was shown in TB. The trend towards the positive LD for DRB1*16-DQB1*05 haplotype in TB patients was not observed in the control group. It seems likely that the presence of DRB1*1601, DQB1*0502 alleles and DRB1*1601-DQB1*0502, DRB1*04-DQB1*03, DRB1*14-DQB1*05 haplotypes may be related to a higher risk of developing TB, whereas low frequency of DQB1*0201 and DRB1*11-DQB1*03 haplotype may be linked to the resistance to TB. 相似文献
82.
S Qin N J Nowak J Zhang S N Sait P G Mayers M J Higgins Y Cheng L Li D J Munroe D S Gerhard B H Weber E Bric D E Housman G A Evans T B Shows 《Proceedings of the National Academy of Sciences of the United States of America》1996,93(7):3149-3154
The development of a highly reliable physical map with landmark sites spaced an average of 100 kbp apart has been a central goal of the Human Genome Project. We have approached the physical mapping of human chromosome 11 with this goal as a primary target. We have focused on strategies that would utilize yeast artificial chromosome (YAC) technology, thus permitting long-range coverage of hundreds of kilobases of genomic DNA, yet we sought to minimize the ambiguities inherent in the use of this technology, particularly the occurrence of chimeric genomic DNA clones. This was achieved through the development of a chromosome 11-specific YAC library from a human somatic cell hybrid line that has retained chromosome 11 as its sole human component.To maximize the efficiency of YAC contig assembly and extension, we have employed an Alu-PCR-based hybridization screening system. This system eliminates many of the more costly and time-consuming steps associated with sequence tagged site content mapping such as sequencing, primer production, and hierarchical screening, resulting in greater efficiency with increased throughput and reduced cost. Using these approaches, we have achieved YAC coverage for >90% of human chromosome 11, with an average intermarker distance of <100 kbp. Cytogenetic localization has been determined for each contig by fluorescent in situ hybridization and/or sequence tagged site content. The YAC contigs that we have generated should provide a robust framework to move forward to sequence-ready templates for the sequencing efforts of the Human Genome Project as well as more focused positional cloning on chromosome 11. 相似文献
83.
Jacek Nowak Marco Ylan Inger Hagerman Olof Nyquist Christer Sylven 《Clinical cardiology》1993,16(9):671-682
Variance electrocardiography (variance ECG) is a new resting procedure for detection of coronary artery disease (CAD). The method measures variability in the electrical expression of the depolarization phase induced by this disease. The time-domain analysis is performed on 220 cardiac cycles using high-fidelity ECG signals from 24 leads, and the phase-locked temporal electrical heterogeneity is expressed as a nondimensional CAD index (CAD-I) with the values of 0–150. This study compares the diagnostic efficiency of variance ECG and exercise stress test in a high prevalence population. A total of 199 symptomatic patients evaluated with coronary angiography was subjected to variance ECG and exercise test on a bicycle ergometer as a continuous ramp. The discriminant accuracy of the two methods was assessed employing the receiver operating characteristic curves constructed by successive consideration of several CAD-I cutpoint values and various threshold criteria based on ST-segment depression exclusively or in combination with exertional chest pain. Of these patients, 175 with CAD (≥ 50% luminal stenosis in 1 + major epicardial arteries) presented a mean CAD-I of 88 ± 22, compared with 70 ± 21 in 24 nonaffected patients (p < 0.01). Variance ECG provided a stochastically significant discrimination (p < 0.01) which was matched by exercise test only when chest pain variable was added to ST-segment depression as a discriminating criterion. Even then, the exercise test diagnosed single-vessel disease with a significantly lower sensitivity. At a cutpoint of CAD-I ≥ 70, compared with ST-segment depression ≥ 1 mm combined with exertional chest pain, the overall sensitivity of variance ECG was significantly higher (p < 0.01) than that of exercise test (79 vs. 48 %). When combined, the two methods identified 93% of coronary angiography positive cases. Variance ECG is an efficient diagnostic method which compares favorably with exercise test for detection of CAD in high prevalence population. 相似文献
84.
James L. Januzzi Annabel A. Chen-Tournoux Robert H. Christenson Gheorghe Doros Judd E. Hollander Phillip D. Levy John T. Nagurney Richard M. Nowak Peter S. Pang Darshita Patel W. Franklin Peacock E. Joy Rivers Elizabeth L. Walters Hanna K. Gaggin 《Journal of the American College of Cardiology》2018,71(11):1191-1200
Background
Contemporary reconsideration of diagnostic N-terminal pro–B-type natriuretic peptide (NT-proBNP) cutoffs for diagnosis of heart failure (HF) is needed.Objectives
This study sought to evaluate the diagnostic performance of NT-proBNP for acute HF in patients with dyspnea in the emergency department (ED) setting.Methods
Dyspneic patients presenting to 19 EDs in North America were enrolled and had blood drawn for subsequent NT-proBNP measurement. Primary endpoints were positive predictive values of age-stratified cutoffs (450, 900, and 1,800 pg/ml) for diagnosis of acute HF and negative predictive value of the rule-out cutoff to exclude acute HF. Secondary endpoints included sensitivity, specificity, and positive (+) and negative (?) likelihood ratios (LRs) for acute HF.Results
Of 1,461 subjects, 277 (19%) were adjudicated as having acute HF. The area under the receiver-operating characteristic curve for diagnosis of acute HF was 0.91 (95% confidence interval [CI]: 0.90 to 0.93; p < 0.001). Sensitivity for age stratified cutoffs of 450, 900, and 1,800 pg/ml was 85.7%, 79.3%, and 75.9%, respectively; specificity was 93.9%, 84.0%, and 75.0%, respectively. Positive predictive values were 53.6%, 58.4%, and 62.0%, respectively. Overall LR+ across age-dependent cutoffs was 5.99 (95% CI: 5.05 to 6.93); individual LR+ for age-dependent cutoffs was 14.08, 4.95, and 3.03, respectively. The sensitivity and negative predictive value for the rule-out cutoff of 300 pg/ml were 93.9% and 98.0%, respectively; LR? was 0.09 (95% CI: 0.05 to 0.13).Conclusions
In acutely dyspneic patients seen in the ED setting, age-stratified NT-proBNP cutpoints may aid in the diagnosis of acute HF. An NT-proBNP <300 pg/ml strongly excludes the presence of acute HF. 相似文献85.
Patrycjusz Stremplewski Katarzyna Komar Krzysztof Palczewski Maciej Wojtkowski Grazyna Palczewska 《Biomedical optics express》2015,6(9):3352-3361
Two-photon microscopy allows visualization of subcellular structures in the living animal retina. In previously reported experiments it was necessary to apply a contact lens to each subject. Extending this technology to larger animals would require fitting a custom contact lens to each animal and cumbersome placement of the living animal head on microscope stage. Here we demonstrate a new device, periscope, for coupling light energy into mouse eye and capturing emitted fluorescence. Using this periscope we obtained images of the RPE and their subcellular organelles, retinosomes, with larger field of view than previously reported. This periscope provides an interface with a commercial microscope, does not require contact lens and its design could be modified to image retina in larger animals.OCIS codes: (170.0110) Imaging systems, (170.4460) Ophthalmic optics and devices, (170.5755) Retina scanning, (180.4315) Nonlinear microscopy, (330.7327) Visual optics, ophthalmic instrumentation 相似文献
86.
Effect of nifedipine on interdigestive gallbladder volume and postprandial gallbladder emptying in man 总被引:3,自引:0,他引:3
Dr Krzysztof Jonderko Andrzej Nowak Anna Kasicka-Jonderko Zbigniew Śliwiński Cezary Kucio 《Digestive diseases and sciences》1991,36(10):1434-1440
The effect of two oral doses (10 and 20 mg) of nifedipine versus placebo on the fasted gallbladder volume and on the meal-induced gallbladder emptying was assessed according to a double-blind study protocol in 12 healthy volunteers. Eight subjects underwent three studies (with placebo and with both nifedipine doses), whereas in two subjects the effect of a 10-mg nifedipine dose, vs placebo and in two others the effect of a 20-mg nifedipine dose vs placebo was examined. The studies were performed on separate days, and the gallbladder volume was measured by means of real-time ultrasonography. Neither placebo nor 20 mg nifedipine per os elicited any significant change in the fasted gallbladder vlume. With 10 mg nifedipine per os a significant increase in the interdigestive gallbladder volume was observed: 22.9±2.9 cm3 before and 26.2±3.2 cm3 after the drug receipt (P<0.005). A trend towards an inhibition of the postprandial gallbladder emptying was observed with 10 mg nifedipineper os without, however, reaching the level of statistical significance. Following 20 mg nifedipineper os, a marked delay in the meal-stimulated gallbladder emptying occurred as reflected by a decrease in the gallbladder ejection fraction from 48.1±4.5% (placebo) to 26.4±5.0% (nifedipine) (P<0.02) at 30 min and from 54.0±3.6% (placebo) to 33.2±4.6% (nifedipine) (P<0.02) at 40 min after the test meal. We conclude that a therapeutic oral dosage of nifedipine has a significant relaxing effect on the human gallbladder. 相似文献
87.
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
88.
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89.
90.
Verena Limperger Ulrich C. Klostermeier Gili Kenet Susanne Holzhauer Martine Alhenc Gelas Ulrich Finckh Ralf Junker Christine Heller Barbara Zieger Karin Kurnik Ralf Knöfler Rolf Mesters Susan Halimeh Ulrike Nowak‐Göttl 《British journal of haematology》2014,167(3):385-393
Venous thromboembolism [TE] is a multifactorial disease and protein C deficiency [PCD] constitutes a major risk factor. In the present study the prevalence of PCD and the clinical presentation at TE onset, including neonatal purpura fulminans, in a cohort of children are reported. In 367 unselected children (0·1–19 years) recruited between July 1996 and December 2013, a comprehensive thrombophilia screening was performed along with recording of anamnestic data. Twenty‐five of 338 children (7·4%) had PCD. Mean age at first TE onset was 10 years (range 0·1–18). Leading thromboembolic manifestations were neonatal purpura fulminans (n = 5), TE of cerebral veins (n = 3), stroke (n = 2) deep veinthrombosis (DVT) of the leg (n = 10), DVT & pulmonary embolism (n = 2) and DVT & pelvic veins (n = 3). Concomitant risk factors for TE were identified in 12 patients, whereas 13 children spontaneously developed TE. A positive family history of DVT was found in 10 children. In this unselected cohort of paediatric patients with symptomatic TE the overall prevalence of PCD was 7·4%; 1·5% presented with neonatal purpura fulminans. Given its clinical implication for patients and family members, thrombophilia testing should be performed and the benefit of medical or educational interventions should be evaluated in this high‐risk population. 相似文献