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991.
Anary Priscila Monteiro Egydio Déborah Yara Alves Cursino dos Santos 《Economic botany》2011,65(3):329-333
Annona (Annonaceae) is an important source of fruits in the Brazilian Cerrado and the Amazon Rainforest. Some Annona species are widely commercialized as fresh fruit or as frozen pulp. Seeds are accustomedly discarded. Our main goal was to
analyze fatty acids profile from seeds of A. crassiflora and A. coriacea from Cerrado, A. montana from Amazon Forest, and three cultivars (A. cherimola cv. Madeira, A. cherimola x A. squamosa cv. Pink’s Mammonth and A. cherimola x A. squamosa cv. Gefner). The total oil yield ranged between 20 and 42% by weight of dry mass. The A cherimola x A. squamosa cv. Gefner has significantly higher total lipid yield than all other samples. 100 g of fruit of this species present 6-8 g
of seeds. Considering the fruit production of Chile (over 221 ton of fruits/year), more than 1300 ton of seed/year could be
obtained, which could provide at least 200 ton of seed oil. Oleic acid was predominant for most samples, but for A. montana linoleic acid was the most abundant FA. Phenotypic variation on FAME profile was observed. These new data are an urgent requirement
for supporting conservation programs, mainly for Cerrado areas in Brazil. 相似文献
992.
Trypanosoma cruzi is a protozoan parasite that infects vertebrates, causing in humans a pathological condition known as Chagas' disease. The infection of host cells by T. cruzi involves a vast collection of molecules, including a family of 85 kDa GPI-anchored glycoproteins belonging to the gp85/trans-sialidase superfamily, which contains a conserved cell-binding sequence (VTVXNVFLYNR) known as FLY, for short. Herein, it is shown that BALB/c mice administered with a single dose (1 μg/animal, intraperitoneally) of FLY-synthetic peptide are more susceptible to infection by T. cruzi, with increased systemic parasitaemia (2-fold) and mortality. Higher tissue parasitism was observed in bladder (7·6-fold), heart (3-fold) and small intestine (3·6-fold). Moreover, an intense inflammatory response and increment of CD4+ T cells (1·7-fold) were detected in the heart of FLY-primed and infected animals, with a 5-fold relative increase of CD4+CD25+FoxP3+ T (Treg) cells. Mice treated with anti-CD25 antibodies prior to infection, showed a decrease in parasitaemia in the FLY model employed. In conclusion, the results suggest that FLY facilitates in vivo infection by T. cruzi and concurs with other factors to improve parasite survival to such an extent that might influence the progression of pathology in Chagas' disease. 相似文献
993.
Morales M Arancibia J Lemus M Silva J Gentina JC Aroca G 《Biotechnology letters》2011,33(11):2141-2145
Sulfolobus metallicus is a hyperthermophilic and chemolithoautotrophic archaeon that uses elemental sulfur as an energy source. Its ability to
oxidize H2S was measured either in the presence or absence of elemental sulphur, showing its ability for using both as an energy source.
A biotrickling filter was set up and a biofilm of S. metallicus was established over the support. The maximum removal capacity of the biotrickling filter reached at 55°C was 40 g S/m3h for input loads higher than 70 g S/m3h. Thus, S. metallicus can be used in a biofiltration system for the treatment of waste gas emissions at high temperatures contaminated with H2S. 相似文献
994.
Cruz M Freitas F Torres CA Reis MA Alves VD 《International journal of biological macromolecules》2011,48(4):695-699
The effect of temperature on the rheology of a new fucose-containing extracellular polysaccharide (EPS) was evaluated. The steady state data revealed a shear-thinning behavior, with the viscosity being immediately recovered when the shear rate was decreased. The mechanical spectra indicated viscous solutions with entangled polymer molecules in the range of temperatures studied (from 15 °C to 65 °C). In addition, the Time-Temperature Superposition principle was successfully applied and the Cox-Merz rule was valid, reinforcing the idea of a thermorheologically simple behavior for the EPS in aqueous solution. Furthermore, the viscous and viscoelastic properties at 25 °C were maintained after consecutive heating and cooling cycles, indicating a good thermal stability under temperature fluctuations. 相似文献
995.
996.
Photodynamic inactivation is a new promising approach to treat bacterial infections. Usually, the evaluation of the efficacy
of this method is done through time-consuming and labor-intensive microbiological test methods. This paper describes the development
and implementation of an optical method to evaluate the photodynamic inactivation of bacteria based on non-invasive diffuse
reflectance measurements. Five Staphylococcus aureus cultures and 15 mice have been used in this study. A skin lesion was created on the back of all animals, and it was contaminated
with S. aureus (5.16 ± 0.013 log CFU/ml). Toluidine Blue O (c = 8.67 × 10 − 3 M) has been used as a photosensitiser agent. The bacterial cultures and animals were exposed to laser radiation (λ = 635 nm, P = 15 mW, DE = 8.654 J/cm2) for 20 min. The photodynamic inactivation of bacteria was monitored by acquiring the wounds’ reflection spectra at different
time points and by microbiological exams on the bioptical material. The good correlation between the diffuse reflectance and
colony-forming units demonstrates the value of this optical method based on diffuse reflectance measurements as a rapid technique
to monitor photodynamic bacterial inactivation. 相似文献
997.
Abreu PA da Silva VA Santos FC Castro HC Riscado CS de Souza MT Ribeiro CP Barbosa JE dos Santos CC Rodrigues CR Lione V Correa BA Cunha AC Ferreira VF de Souza MC Paixão IC 《Current microbiology》2011,62(5):1349-1354
Herpes simplex virus is an important human pathogen responsible for a range of diseases from mild uncomplicated mucocutaneous infections to life-threatening ones. Currently, the emergence of Herpes simplex virus resistant strains increased the need for more effective and less cytotoxic drugs for Herpes treatment. In this work, we synthesized a series of oxoquinoline derivatives and experimentally evaluated the antiviral activity against acyclovir resistant HSV-1 strain as well as their cytotoxity profile. The most active compound (3b), named here as Fluoroxaq-3b, showed a promising profile with a better cytotoxicity profile than acyclovir. The theoretical analysis of the structure-activity relationship of these compounds revealed some stereoelectronic properties such as lower LUMO energy and lipophilicity, besides a higher polar surface area and number of hydrogen bond acceptor groups as important parameters for the antiviral activity. Fluoroxaq-3b showed a good oral theoretical bioavailability, according to Lipinski rule of five, with a promising profile for further in vivo analysis. 相似文献
998.
Maria Laura Aon-Bertolino Juan Ignacio Romero Pablo Galeano Mariana Holubiec Maria Sol Badorrey Gustavo Ezequiel Saraceno Eva-Maria Hanschmann Christopher Horst Lillig Francisco Capani 《Biochimica et Biophysica Acta (BBA)/General Subjects》2011
Background
The oxidoreductases of the thioredoxin (Trx) family of proteins play a major role in the cellular response to oxidative stress. Redox imbalance is a major feature of brain damage. For instance, neuronal damage and glial reaction induced by a hypoxic–ischemic episode is highly related to glutamate excitotoxicity, oxidative stress and mitochondrial dysfunction. Most animal models of hypoxia–ischemia in the central nervous system (CNS) use rats to study the mechanisms involved in neuronal cell death, however, no comprehensive study on the localization of the redox proteins in the rat CNS was available.Methods
The aim of this work was to study the distribution of the following proteins of the thioredoxin and glutathione/glutaredoxin (Grx) systems in the rat CNS by immunohistochemistry: Trx1, Trx2, TrxR1, TrxR2, Txnip, Grx1, Grx2, Grx3, Grx5, and γ-GCS, peroxiredoxin 1 (Prx1), Prx2, Prx3, Prx4, Prx5, and Prx6. We have focused on areas most sensitive to a hypoxia–ischemic insult: Cerebellum, striatum, hippocampus, spinal cord, substantia nigra, cortex and retina.Results and conclusions
Previous studies implied that these redox proteins may be distributed in most cell types and regions of the CNS. Here, we have observed several remarkable differences in both abundance and regional distribution that point to a complex interplay and crosstalk between the proteins of this family.General significance
We think that these data might be helpful to reveal new insights into the role of thiol redox pathways in the pathogenesis of hypoxia–ischemia insults and other disorders of the CNS.This article is part of a Special Issue entitled Human and Murine Redox Protein Atlases. 相似文献999.
1000.
Burgi K Cavalleri MT Alves AS Britto LR Antunes VR Michelini LC 《American journal of physiology. Regulatory, integrative and comparative physiology》2011,300(2):R264-R271
Vasomotor control by the sympathetic nervous system presents substantial heterogeneity within different tissues, providing appropriate homeostatic responses to maintain basal/stimulated cardiovascular function both at normal and pathological conditions. The availability of a reproducible technique for simultaneous measurement of sympathetic drive to different tissues is of great interest to uncover regional patterns of sympathetic nerve activity (SNA). We propose the association of tyrosine hydroxylase immunoreactivity (THir) with image analysis to quantify norepinephrine (NE) content within nerve terminals in arteries/arterioles as a good index for regional sympathetic outflow. THir was measured in fixed arterioles of kidney, heart, and skeletal muscle of Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR) (123 ± 2 and 181 ± 4 mmHg, 300 ± 8 and 352 ± 8 beats/min, respectively). There was a differential THir distribution in both groups: higher THir was observed in the kidney and skeletal muscle (~3-4-fold vs. heart arterioles) of WKY; in SHR, THir was increased in the kidney and heart (2.4- and 5.3-fold vs. WKY, respectively) with no change in the skeletal muscle arterioles. Observed THir changes were confirmed by either: 1) determination of NE content (high-performance liquid chromatography) in fresh tissues (SHR vs. WKY): +34% and +17% in kidney and heart, respectively, with no change in the skeletal muscle; 2) direct recording of renal (RSNA) and lumbar SNA (LSNA) in anesthetized rats, showing increased RSNA but unchanged LSNA in SHR vs. WKY. THir in skeletal muscle arterioles, NE content in femoral artery, and LSNA were simultaneously reduced by exercise training in the WKY group. Results indicate that THir is a valuable technique to simultaneously evaluate regional patterns of sympathetic activity. 相似文献