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461.
Juliana L. Bernardoni Leijiane F. Sousa Luciana S. Wermelinger Aline S. Lopes Benedito C. Prezoto Solange M. T. Serrano Russolina B. Zingali Ana M. Moura-da-Silva 《PloS one》2014,9(10)
Snake venom metalloproteinases (SVMPs) are major components in most viperid venoms that induce disturbances in the hemostatic system and tissues of animals envenomated by snakes. These disturbances are involved in human pathology of snake bites and appear to be essential for the capture and digestion of snake''s prey and avoidance of predators. SVMPs are a versatile family of venom toxins acting on different hemostatic targets which are present in venoms in distinct structural forms. However, the reason why a large number of different SVMPs are expressed in some venoms is still unclear. In this study, we evaluated the interference of five isolated SVMPs in blood coagulation of humans, birds and small rodents. P-III class SVMPs (fractions Ic, IIb and IIc) possess gelatinolytic and hemorrhagic activities, and, of these, two also show fibrinolytic activity. P-I class SVMPs (fractions IVa and IVb) are only fibrinolytic. P-III class SVMPs reduced clotting time of human plasma. Fraction IIc was characterized as prothrombin activator and fraction Ic as factor X activator. In the absence of Ca2+, a firm clot was observed in chicken blood samples with fractions Ic, IIb and partially with fraction IIc. In contrast, without Ca2+, only fraction IIc was able to induce a firm clot in rat blood. In conclusion, functionally distinct forms of SVMPs were found in B. neuwiedi venom that affect distinct mechanisms in the coagulation system of humans, birds and small rodents. Distinct SVMPs appear to be more specialized to rat or chicken blood, strengthening the current hypothesis that toxin diversity enhances the possibilities of the snakes for hunting different prey or evading different predators. This functional diversity also impacts the complexity of human envenoming since different hemostatic mechanisms will be targeted by SVMPs accounting for the complexity of the response of humans to venoms. 相似文献
462.
Nelson Henrique de Almeida Curi Amanda Soriano Araújo Fábia Souza Campos Zélia Inês Portela Lobato Solange Maria Gennari Maria Fernanda Vianna Marvulo Jean Carlos Ramos Silva Sônia Aparecida Talamoni 《Biodiversity and Conservation》2010,19(12):3513-3524
Wild canids are under many pressures, including habitat loss, fragmentation and disease. The current lack of information on
the status of wildlife health may hamper conservation efforts in Brazil. In this paper, we examined the prevalence of canine
pathogens in 21 free-ranging wild canids, comprising 12 Cerdocyon thous (crab-eating fox), 7 Chrysocyon brachyurus (maned wolf), 2 Lycalopex vetulus (hoary fox), and 70 non-vaccinated domestic dogs from the Serra do Cipó National Park area, Southeast Brazil. For wild canids,
seroprevalence of antibodies to canine parvovirus, canine adenovirus, canine coronavirus and Toxoplasma gondii was 100 (21/21), 33 (7/21), 5 (1/19) and 68 (13/19) percent, respectively. Antibodies against canine distemper virus, Neospora caninum or Babesia spp. were not found. We tested domestic dogs for antibodies to canine parvovirus, canine distemper virus and Babesia spp., and seroprevalences were 59 (41/70), 66 (46/70), and 42 (40/70) percent, respectively, with significantly higher prevalence
in domestic dogs for CDV (P < 0.001) and Babesia spp. (P = 0.002), and in wild canids for CPV (P < 0.001). We report for the first time evidence of exposure to canine coronavirus in wild hoary foxes, and Platynossomun sp. infection in wild maned wolves. Maned wolves are more exposed to helminths than crab-eating foxes, with a higher prevalence
of Trichuridae and Ancylostomidae in the area. The most common ectoparasites were Amblyomma cajennense, A. tigrinum, and Pulex irritans. Such data is useful information on infectious diseases of Brazilian wild canids, revealing pathogens as a threat to wild
canids in the area. Control measures are discussed. 相似文献
463.
464.
Flávia S. Kubrusly Solange de Lima Netto Dmitri Iourtov Isaias Raw Pedro Soares de Araujo 《Biotechnology letters》2000,22(15):1251-1253
An exogenous natural lung surfactant obtained from minced pig lungs can be produced by a technology using a low cost, DEAE-cellulose adsorbent. This surfactant is composed mainly with phospholipids and the two hydrophobic polypeptides, SP-B and SP-C, both of which are necessary for optimal function of surfactants used for treatment of respiratory distress syndrome. 相似文献
465.
Stomatal characteristics in different habitat forms of Brazilian species of Epidendrum (Orchidaceae)
Giulio Cesare Stancato Solange Cristina Mazzoni-Viveiros Agnes Elisete Luchi 《Nordic Journal of Botany》1999,19(3):271-275
Brazilian species of the genus Epidendrum , distributed over various habitats, were analysed for epidermal structure to test correlations between habitat form and variation in stomatal parameters. This study confirmed the tendency for stomatal index values to increase in the apical direction of the foliar surface in this genus. The generally held view that there are a smaller number of stomata on the adaxial surface in amphistomatic leaves was contradicted for E. vesicatum , whose pendent sympodia showed that the adaxial foliar surfaces assume the abaxial position in relation to light incidence. 相似文献
466.
Solange de Lauzon Daniel Mansuy Jean-Pierre Mahy 《European journal of biochemistry》2002,269(2):470-480
An artificial peroxidase-like hemoprotein has been obtained by associating a monoclonal antibody, 13G10, and its iron(III)-alpha,alpha,alpha,beta-meso-tetrakis(ortho-carboxyphenyl)porphyrin [Fe(ToCPP)] hapten. In this antibody, about two-thirds of the porphyrin moiety is inserted in the binding site, its ortho-COOH substituents being recognized by amino-acids of the protein, and a carboxylic acid side chain of the protein acts as a general acid base catalyst in the heterolytic cleavage of the O-O bond of H2O2, but no amino-acid residue is acting as an axial ligand of the iron.We here show that the iron of 13G10-Fe(ToCPP) is able to bind, like that of free Fe(ToCPP), two small ligands such as CN-, but only one imidazole ligand, in contrast to to the iron(III) of Fe(ToCPP) that binds two. This phenomenon is general for a series of monosubstituted imidazoles, the 2- and 4-alkyl-substituted imidazoles being the best ligands, in agreement with the hydrophobic character of the antibody binding site. Complexes of antibody 13G10 with less hindered iron(III)-tetraarylporphyrins bearing only one [Fe(MoCPP)] or two meso-[ortho-carboxyphenyl] substituents [Fe(DoCPP)] also bind only one imidazole. Finally, peroxidase activity studies show that imidazole inhibits the peroxidase activity of 13G10-Fe(ToCPP) whereas it increases that of 13G10-Fe(DoCPP). This could be interpreted by the binding of the imidazole ligand on the iron atom which probably occurs in the case of 13G10-Fe(ToCPP) on the less hindered face of the porphyrin, close to the catalytic COOH residue, whereas in the case of 13G10-Fe(DoCPP) it can occur on the other face of the porphyrin. The 13G10-Fe(DoCPP)-imidazole complex thus constitutes a nice artificial peroxidase-like hemoprotein, with the axial imidazole ligand of the iron mimicking the proximal histidine of peroxidases and a COOH side chain of the antibody acting as a general acid-base catalyst like the distal histidine of peroxidases does. 相似文献
467.
Marta Susana Dardanelli Paola Solange González Daniela Beatriz Medeot Natalia Soledad Paulucci Miguel Ángel Bueno Mirta Beatriz Garcia 《Symbiosis (Philadelphia, Pa.)》2009,47(3):175-180
The effects of saline and osmotic stress on four peanut rhizobia, plant growth and symbiotic N2-fixation inArachis hypogaea were studied. Abiotic stress was applied by adding either 100 mM NaCl or 20 mM PEG6000. At the rhizobial level,Bradyrhizobium ATCC10317 and TAL1000 showed stronger tolerance to stress than TAL1371 and SEMIA6144. The effect of salinity on the bacterium-plant
association was studied by using the variety Blanco Manfredi M68. In the absence of stresses, all the strains induced a significantly
higher number of nodules on the roots, although TAL1371 and SEMIA6144 were more effective. Both stresses affected the interaction
process, while TALl371 was the best partner. 相似文献
468.
Alcione Silva de Carvalho Kelly Salom?o Solange Lisboa de Castro Taline Ramos Conde Helena Pereira da Silva Zamith Ernesto Raúl Caffarena Belinda Suzette Hall Shane Robert Wilkinson Núbia Boechat 《Memórias do Instituto Oswaldo Cruz》2014,109(3):315-323
Megazol (7) is a 5-nitroimidazole that is highly active against Trypanosoma
cruzi and Trypanosoma brucei, as well as drug-resistant
forms of trypanosomiasis. Compound 7 is not used clinically due to its mutagenic and
genotoxic properties, but has been largely used as a lead compound. Here, we compared
the activity of 7 with its 4H-1,2,4-triazole bioisostere (8) in
bloodstream forms of T. brucei and T. cruzi and
evaluated their activation by T. brucei type I nitroreductase
(TbNTR) enzyme. We also analysed the cytotoxic and genotoxic
effects of these compounds in whole human blood using Comet and fluorescein
diacetate/ethidium bromide assays. Although the only difference between 7 and 8 is
the substitution of sulphur (in the thiadiazole in 7) for nitrogen (in the triazole
in 8), the results indicated that 8 had poorer antiparasitic activity than 7 and was
not genotoxic, whereas 7 presented this effect. The determination of Vmax indicated
that although 8 was metabolised more rapidly than 7, it bounds to the
TbNTR with better affinity, resulting in equivalent kcat/KM
values. Docking assays of 7 and 8 performed within the active site of a homology
model of the TbNTR indicating that 8 had greater affinity than
7. 相似文献
469.
470.
Ilaria De Pasquale Raffaella Di Cagno Solange Buchin Maria De Angelis Marco Gobbetti 《Applied and environmental microbiology》2014,80(19):6243-6255
Pyrosequencing of the 16S rRNA targeting RNA, community-level physiological profiles made with Biolog EcoPlates, proteolysis, and volatile component (VOC) analyses were mainly used to characterize the manufacture and ripening of the pasta filata cheese Caciocavallo Pugliese. Plate counts revealed that cheese manufacture affected the microbial ecology. The results agreed with those from culture-independent approaches. As shown by urea-PAGE, reverse-phase high pressure liquid chromatography (RP-HPLC), and free-amino-acid (FAA) analyses, the extent of secondary proteolysis mainly increased after 30 to 45 days of ripening. VOCs and volatile free fatty acids (VFFA) were identified by a purge-and-trap method (PT) and solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS), respectively. Except for aldehydes, the levels of most of VOCs and VFFA mainly increased from 30 to 45 days onwards. As shown through pyrosequencing analysis, raw cows'' milk was contaminated by Firmicutes (53%), Proteobacteria (39%), Bacteroidetes (7.8%), Actinobacteria (0.06%), and Fusobacteria (0.03%), with heterogeneity at the genus level. The primary starter Streptococcus thermophilus dominated the curd population. Other genera occurred at low incidence or sporadically. The microbial dynamics reflected on the overall physiological diversity. At 30 days, a microbial succession was clearly highlighted. The relative abundance of Streptococcus sp. and especially St. thermophilus decreased, while that of Lactobacillus casei, Lactobacillus sp., and especially Lactobacillus paracasei increased consistently. Despite the lower relative abundance compared to St. thermophilus, mesophilic lactobacilli were the only organisms positively correlated with the concentration of FAAs, area of hydrophilic peptide peaks, and several VOCs (e.g., alcohols, ketones, esters and all furans). This study showed that a core microbiota was naturally selected during middle ripening, which seemed to be the main factor responsible for cheese ripening. 相似文献