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871.
Atrial natriuretic peptide, B-type natriuretic peptide, and serum collagen markers after acute myocardial infarction. 总被引:7,自引:0,他引:7
Jarkko Magga Mikko Puhakka Seppo Hietakorpi Kari Punnonen Paavo Uusimaa Juha Risteli Olli Vuolteenaho Heikki Ruskoaho Keijo Peuhkurinen 《Journal of applied physiology》2004,96(4):1306-1311
Experimental data suggest that atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP) act locally as antifibrotic factors in heart. We investigated the interrelationships of natriuretic peptides and collagen markers in 93 patients receiving thrombolytic treatment for their first acute myocardial infarction (AMI). Collagen formation following AMI, evaluated as serum levels of amino terminal propeptide of type III procollagen, correlated with NH(2)-terminal proANP (r = 0.45, P < 0.001), BNP (r = 0.55, P < 0.001) and NH(2)-terminal proBNP (r = 0.50, P < 0.01) on day 4 after thrombolysis. Levels of intact amino terminal propeptide of type I procollagen decreased by 34% (P < 0.001), and levels of carboxy terminal cross-linked telopeptide of type I collagen (ICTP) increased by 65% (P < 0.001). ICTP levels correlated with NH(2)-terminal proBNP (r = 0.25, P < 0.05) and BNP (r = 0.28, P < 0.05) on day 4. Our results suggest that ANP and BNP may act as regulators of collagen scar formation and left ventricular remodeling after AMI in humans. Furthermore, degradation of type I collagen is increased after AMI and may be regulated by BNP. 相似文献
872.
Noninvasive bioluminescence imaging in small animals 总被引:3,自引:0,他引:3
Zinn KR Chaudhuri TR Szafran AA O'Quinn D Weaver C Dugger K Lamar D Kesterson RA Wang X Frank SJ 《ILAR journal / National Research Council, Institute of Laboratory Animal Resources》2008,49(1):103-115
There has been a rapid growth of bioluminescence imaging applications in small animal models in recent years, propelled by the availability of instruments, analysis software, reagents, and creative approaches to apply the technology in molecular imaging. Advantages include the sensitivity of the technique as well as its efficiency, relatively low cost, and versatility. Bioluminescence imaging is accomplished by sensitive detection of light emitted following chemical reaction of the luciferase enzyme with its substrate. Most imaging systems provide 2-dimensional (2D) information in rodents, showing the locations and intensity of light emitted from the animal in pseudo-color scaling. A 3-dimensional (3D) capability for bioluminescence imaging is now available, but is more expensive and less efficient; other disadvantages include the requirement for genetically encoded luciferase, the injection of the substrate to enable light emission, and the dependence of light signal on tissue depth. All of these problems make it unlikely that the method will be extended to human studies. However, in small animal models, bioluminescence imaging is now routinely applied to serially detect the location and burden of xenografted tumors, or identify and measure the number of immune or stem cells after an adoptive transfer. Bioluminescence imaging also makes it possible to track the relative amounts and locations of bacteria, viruses, and other pathogens over time. Specialized applications of bioluminescence also follow tissue-specific luciferase expression in transgenic mice, and monitor biological processes such as signaling or protein interactions in real time. In summary, bioluminescence imaging has become an important component of biomedical research that will continue in the future. 相似文献
873.
Silander K Alanne M Kristiansson K Saarela O Ripatti S Auro K Karvanen J Kulathinal S Niemelä M Ellonen P Vartiainen E Jousilahti P Saarela J Kuulasmaa K Evans A Perola M Salomaa V Peltonen L 《PloS one》2008,3(10):e3615
Background
Cardiovascular disease (CVD) incidence, complications and burden differ markedly between women and men. Although there is variation in the distribution of lifestyle factors between the genders, they do not fully explain the differences in CVD incidence and suggest the existence of gender-specific genetic risk factors. We aimed to estimate whether the genetic risk profiles of coronary heart disease (CHD), ischemic stroke and the composite end-point of CVD differ between the genders.Methodology/Principal Findings
We studied in two Finnish population cohorts, using the case-cohort design the association between common variation in 46 candidate genes and CHD, ischemic stroke, CVD, and CVD-related quantitative risk factors. We analyzed men and women jointly and also conducted genotype-gender interaction analysis. Several allelic variants conferred disease risk for men and women jointly, including rs1801020 in coagulation factor XII (HR = 1.31 (1.08–1.60) for CVD, uncorrected p = 0.006 multiplicative model). Variant rs11673407 in the fucosyltransferase 3 gene was strongly associated with waist/hip ratio (uncorrected p = 0.00005) in joint analysis. In interaction analysis we found statistical evidence of variant-gender interaction conferring risk of CHD and CVD: rs3742264 in the carboxypeptidase B2 gene, p(interaction) = 0.009 for CHD, and rs2774279 in the upstream stimulatory factor 1 gene, p(interaction) = 0.007 for CHD and CVD, showed strong association in women but not in men, while rs2069840 in interleukin 6 gene, p(interaction) = 0.004 for CVD, showed strong association in men but not in women (uncorrected p-values). Also, two variants in the selenoprotein S gene conferred risk for ischemic stroke in women, p(interaction) = 0.003 and 0.007. Importantly, we identified a larger number of gender-specific effects for women than for men.Conclusions/Significance
A false discovery rate analysis suggests that we may expect half of the reported findings for combined gender analysis to be true positives, while at least third of the reported genotype-gender interaction results are true positives. The asymmetry in positive findings between the genders could imply that genetic risk loci for CVD are more readily detectable in women, while for men they are more confounded by environmental/lifestyle risk factors. The possible differences in genetic risk profiles between the genders should be addressed in more detail in genetic studies of CVD, and more focus on female CVD risk is also warranted in genome-wide association studies. 相似文献874.
A New Rapid On-Line Imaging Method to Determine Particle Size Distribution of Granules 总被引:1,自引:0,他引:1
The purpose of this research was to study the feasibility of the new image analysis method in the particle size determination
of the granules. The method is capable of forming a three-dimensional topographic image of a sample surface from a digital
picture. In the method, a flat granule bed surface was illuminated from three different directions, using the three primary
colors (red, green, and blue). One color picture was taken by a digital camera, after which a topographic image of the object
surface was constructed. The particle size distribution was then calculated from the image data. The particle size analysis
method was tested both off-line and on-line. Off-line particle size measurement results determined by the image analysis method
corresponded quite well to those of sieve analysis in the size fraction range 250–1,000 μm. In on-line application, images
were successfully retrieved and median granule size trend could be calculated and followed during fluid bed granulations. 相似文献
875.
Mossong J Hens N Jit M Beutels P Auranen K Mikolajczyk R Massari M Salmaso S Tomba GS Wallinga J Heijne J Sadkowska-Todys M Rosinska M Edmunds WJ 《PLoS medicine》2008,5(3):e74
Background
Mathematical modelling of infectious diseases transmitted by the respiratory or close-contact route (e.g., pandemic influenza) is increasingly being used to determine the impact of possible interventions. Although mixing patterns are known to be crucial determinants for model outcome, researchers often rely on a priori contact assumptions with little or no empirical basis. We conducted a population-based prospective survey of mixing patterns in eight European countries using a common paper-diary methodology.Methods and Findings
7,290 participants recorded characteristics of 97,904 contacts with different individuals during one day, including age, sex, location, duration, frequency, and occurrence of physical contact. We found that mixing patterns and contact characteristics were remarkably similar across different European countries. Contact patterns were highly assortative with age: schoolchildren and young adults in particular tended to mix with people of the same age. Contacts lasting at least one hour or occurring on a daily basis mostly involved physical contact, while short duration and infrequent contacts tended to be nonphysical. Contacts at home, school, or leisure were more likely to be physical than contacts at the workplace or while travelling. Preliminary modelling indicates that 5- to 19-year-olds are expected to suffer the highest incidence during the initial epidemic phase of an emerging infection transmitted through social contacts measured here when the population is completely susceptible.Conclusions
To our knowledge, our study provides the first large-scale quantitative approach to contact patterns relevant for infections transmitted by the respiratory or close-contact route, and the results should lead to improved parameterisation of mathematical models used to design control strategies. 相似文献876.
Palsdottir A Helgason A Palsson S Bjornsson HT Bragason BT Gretarsdottir S Thorsteinsdottir U Olafsson E Stefansson K 《PLoS genetics》2008,4(6):e1000099
Hereditary cystatin C amyloid angiopathy (HCCAA) is an autosomal dominant disease with high penetrance, manifest by brain hemorrhages in young normotensive adults. In Iceland, this condition is caused by the L68Q mutation in the cystatin C gene, with contemporary carriers reaching an average age of only 30 years. Here, we report, based both on linkage disequilibrium and genealogical evidence, that all known copies of this mutation derive from a common ancestor born roughly 18 generations ago. Intriguingly, the genealogies reveal that obligate L68Q carriers born 1825 to 1900 experienced a drastic reduction in life span, from 65 years to the present-day average. At the same time, a parent-of-origin effect emerged, whereby maternal inheritance of the mutation was associated with a 9 year reduction in life span relative to paternal inheritance. As these trends can be observed in several different extended families, many generations after the mutational event, it seems likely that some environmental factor is responsible, perhaps linked to radical changes in the life-style of Icelanders during this period. A mutation with such radically different phenotypic effects in reaction to normal variation in human life-style not only opens the possibility of preventive strategies for HCCAA, but it may also provide novel insights into the complex relationship between genotype and environment in human disease. 相似文献
877.
878.
Sanya Hokputsa Waraporn Gerddit Sunanta Pongsamart Kari Inngjerdingen Thomas Heinze Andreas Koschella Stephen E. Harding Berit S. Paulsen 《Carbohydrate polymers》2004,56(4):471-481
Crude, pharmaceutically useful water-soluble polysaccharides have been isolated from durian rinds (Durio zibethinus) by hot water extraction followed by ethanol precipitation. The polysaccharides were fractionated by anion exchange chromatography and size exclusion chromatography. Characterisation of the sub-fractions by methanolysis, methylation analysis and NMR spectroscopy revealed that the principal components were pectic polysaccharides with starch as a contaminant. Physical features namely molecular weight (Mw) and intrinsic viscosity of the main fractions were investigated by size exclusion chromatography coupled to multi angle laser light scattering (SEC/MALLS) and capillary viscometer, respectively. The main fractions were subjected to the complement-fixation assay and the relationship of the chemical features of the polysaccharide fractions with their activity was also considered. 相似文献
879.
880.
Anna-Lotta Kaivorinne Johanna Krüger Katja Kuivaniemi Hannu Tuominen Virpi Moilanen Kari Majamaa Anne M Remes 《BMC neurology》2008,8(1):48