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Sara M. Robledo Lina M. Carrillo Alejandro Daza Adriana M. Restrepo Diana L. Mu?oz Jairo Tobón Javier D. Murillo Anderson López Carolina Ríos Carol V. Mesa Yulieth A. Upegui Alejandro Valencia-Tobón Karina Mondragón-Shem Berardo Rodríguez Iván D. Vélez 《Journal of visualized experiments : JoVE》2012,(62)
Traditionally, hamsters are experimentally inoculated in the snout or the footpad. However in these sites an ulcer not always occurs, measurement of lesion size is a hard procedure and animals show difficulty to eat, breathe and move because of the lesion. In order to optimize the hamster model for cutaneous leishmaniasis, young adult male and female golden hamsters (Mesocricetus auratus) were injected intradermally at the dorsal skin with 1 to 1.5 x l07 promastigotes of Leishmania species and progression of subsequent lesions were evaluated for up to 16 weeks post infection. The golden hamster was selected because it is considered the adequate bio-model to evaluate drugs against Leishmania as they are susceptible to infection by different species. Cutaneous infection of hamsters results in chronic but controlled lesions, and a clinical evolution with signs similar to those observed in humans. Therefore, the establishment of the extent of infection by measuring the size of the lesion according to the area of indurations and ulcers is feasible. This approach has proven its versatility and easy management during inoculation, follow up and characterization of typical lesions (ulcers), application of treatments through different ways and obtaining of clinical samples after different treatments. By using this method the quality of animal life regarding locomotion, search for food and water, play and social activities is also preserved. 相似文献
115.
Luisa Cabezas Carolina Calderon Luis Miguel Medina Isabela Bahamon Martha Cardenas Adriana Jimena Bernal Andrés Gonzalez Silvia Restrepo 《Journal of microbiology (Seoul, Korea)》2012,50(6):1009-1013
Endophytes are microorganisms that asymptomatically invade plant tissues. They can stimulate plant growth and/or provide defense against pathogen attacks through the production of secondary metabolites. Most endophyte species are still unknown, and because they may have several applications, the study of their metabolic capabilities is essential. We characterized 100 endophytes isolated from Espeletia spp., a genus unique to the paramo ecosystem, an extreme environment in the Andean mountain range. We evaluated the cellulolytic potential of these endophytes on the saccharification of the oil palm empty fruit bunch (OPEFB). The total cellulolytic activity was measured for each endophyte on filter paper (FPA). In addition, the specific carboxymethyl cellulase (CMCase), exoglucanase, and β-glucosidase activities were determined. We found four fungi positive for cellulases. Of these fungi, Penicillium glabrum had the highest cellulolytic activity after partial purification, with maximal CMCase, exoglucanase and β-glucosidase enzyme activities of 44.5, 48.3, and 0.45 U/ml, respectively. Our data showed that the bioprospection of fungi and the characterization of their enzymes may facilitate the process of biofuel production. 相似文献
116.
Persistent antibody and T cell responses induced by HIV-1 DNA vaccine delivered by electroporation 总被引:1,自引:0,他引:1
Cristillo AD Weiss D Hudacik L Restrepo S Galmin L Suschak J Draghia-Akli R Markham P Pal R 《Biochemical and biophysical research communications》2008,366(1):29-35
Intramuscular needle injection of HIV-1 DNA vaccines typically elicits weak immune responses in immunized individuals. To improve such responses, the immunogenicity of a vaccine consisting of electroporated DNA followed by intramuscular protein boost was evaluated in rabbits and macaques. In macaques, electroporation of low dose DNA encoding HIV-1 env followed by gp120 protein elicited Th1 cytokines and functional CTL that persisted for over 1 year. In both macaques and rabbits, robust anti-envelope antibodies, elicited by electroporated DNA, were augmented by gp120 protein and such responses neutralized sensitive SHIV isolates. These findings highlight efficient priming of immune responses by electroporated DNA that in conjunction with protein boost may give rise to long-term immunity in immunized hosts. 相似文献
117.
A rabbit ventricular action potential model replicating cardiac dynamics at rapid heart rates
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Mahajan A Shiferaw Y Sato D Baher A Olcese R Xie LH Yang MJ Chen PS Restrepo JG Karma A Garfinkel A Qu Z Weiss JN 《Biophysical journal》2008,94(2):392-410
Mathematical modeling of the cardiac action potential has proven to be a powerful tool for illuminating various aspects of cardiac function, including cardiac arrhythmias. However, no currently available detailed action potential model accurately reproduces the dynamics of the cardiac action potential and intracellular calcium (Cai) cycling at rapid heart rates relevant to ventricular tachycardia and fibrillation. The aim of this study was to develop such a model. Using an existing rabbit ventricular action potential model, we modified the L-type calcium (Ca) current (ICa,L) and Cai cycling formulations based on new experimental patch-clamp data obtained in isolated rabbit ventricular myocytes, using the perforated patch configuration at 35-37°C. Incorporating a minimal seven-state Markovian model of ICa,L that reproduced Ca- and voltage-dependent kinetics in combination with our previously published dynamic Cai cycling model, the new model replicates experimentally observed action potential duration and Cai transient alternans at rapid heart rates, and accurately reproduces experimental action potential duration restitution curves obtained by either dynamic or S1S2 pacing. 相似文献
118.
Tabares CJ Montoya AF Arboleda L Echeverri A Restrepo LF Olivera-Angel M 《Revista de biología tropical》2006,54(1):179-187
Effect of pluviosity and sun shine on sperm production and seminal characteristics of the fish Brycon henni (Pisces: Characidae). In Colombia the fish Brycon henni is a protected endemic species. It inhabits water bodies in coffee producing areas (700-1900 ma.s.l.; 4 degrees 35'56" N - 74 degrees 04'51" W; 18-28 degrees C). Insufficient knowledge of its basic biology and behavior prevent the commercial culture of this promising fish. We studied the production and sperm physiology of captive males. Along a year 20 samples were taken from each of 10 males. The sample was obtained by abdominal cefalo-caudal massage and transported to the laboratory at 4 degrees C. Except for September and October (maximum rainfall), sperm was always obtained in at least 50% of the males. Color, osmolality and pH were similar in all the samples. Volume, concentration, viability, motility and activation time were variable: sunshine had a positive effect on volume (Spearman p < 0.05) and on sperm concentration (Spearman p < 0.05) while pluviosity had a negative effect on volume and viability. The proportion of ions (Na, K, Mg, Ca) was constant along the year; Na being 10-fold higher than K and 100-fold higher than Mg and Ca; however the absolute concentration of all ions was slightly higher in April and in July (with no apparent relation with the other variables analyzed). 相似文献
119.
There are wide variations in the threshold used to define in vitro resistance of Plasmodium falciparum to amodiaquine (AQ), probably due to differences in methodology and interpretation. In vitro susceptibility data of Colombian P. falciparum strains to AQ and N-desethylamodiaquine is used to illustrate the need to standardized methodologies and compare inhibitory concentrations, instead of resistant/susceptible phenotypes, when studying the mechanisms of resistance to AQ and monitoring drug susceptibility trends in the field. 相似文献
120.
Deniz Koyuncu Muhammad Khalid Khan Niazi Thomas Tavolara Claudia Abeijon Melanie L. Ginese Yanghui Liao Carolyn Mark Aubrey Specht Adam C. Gower Blanca I. Restrepo Daniel M. Gatti Igor Kramnik Metin Gurcan Bülent Yener Gillian Beamer 《PLoS pathogens》2021,17(8)
More humans have died of tuberculosis (TB) than any other infectious disease and millions still die each year. Experts advocate for blood-based, serum protein biomarkers to help diagnose TB, which afflicts millions of people in high-burden countries. However, the protein biomarker pipeline is small. Here, we used the Diversity Outbred (DO) mouse population to address this gap, identifying five protein biomarker candidates. One protein biomarker, serum CXCL1, met the World Health Organization’s Targeted Product Profile for a triage test to diagnose active TB from latent M.tb infection (LTBI), non-TB lung disease, and normal sera in HIV-negative, adults from South Africa and Vietnam. To find the biomarker candidates, we quantified seven immune cytokines and four inflammatory proteins corresponding to highly expressed genes unique to progressor DO mice. Next, we applied statistical and machine learning methods to the data, i.e., 11 proteins in lungs from 453 infected and 29 non-infected mice. After searching all combinations of five algorithms and 239 protein subsets, validating, and testing the findings on independent data, two combinations accurately diagnosed progressor DO mice: Logistic Regression using MMP8; and Gradient Tree Boosting using a panel of 4: CXCL1, CXCL2, TNF, IL-10. Of those five protein biomarker candidates, two (MMP8 and CXCL1) were crucial for classifying DO mice; were above the limit of detection in most human serum samples; and had not been widely assessed for diagnostic performance in humans before. In patient sera, CXCL1 exceeded the triage diagnostic test criteria (>90% sensitivity; >70% specificity), while MMP8 did not. Using Area Under the Curve analyses, CXCL1 averaged 94.5% sensitivity and 88.8% specificity for active pulmonary TB (ATB) vs LTBI; 90.9% sensitivity and 71.4% specificity for ATB vs non-TB; and 100.0% sensitivity and 98.4% specificity for ATB vs normal sera. Our findings overall show that the DO mouse population can discover diagnostic-quality, serum protein biomarkers of human TB. 相似文献