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961.
Five known secondary metabolites, chrysophanol ( 1 ), 7,7′‐biphyscion ( 2 ), secalonic acid D ( 3 ), mannitol ( 4 ) and trehalose ( 5 ) were isolated for the first time from the extracts of the fungus Phialomyces macrosporus. Their structures were elucidated by NMR methods (1D and 2D NMR analysis), optical activity and ESI‐MS. Complete 1H and 13C assignments were performed for compound 2 . The antimicrobial activity was evaluated by serial microdilution assay for compounds 2 and 3 and results showed that compound 3 exhibited a significant growth inhibition at concentrations of 15.6 mg/ml (S. aureus and S. choleraesius) and 0.97 mg/mL (B. subtilis), comparable to the positive control. 相似文献
962.
Gilles Rousserie Regina Grinevich Kristina Brazhnik Klervi Even-Desrumeaux Brigitte Reveil Thierry Tabary Patrick Chames Daniel Baty Jacques H.M. Cohen Igor Nabiev Alyona Sukhanova 《Analytical biochemistry》2015
Compact single-domain antibodies (sdAbs) are nearly 13 times smaller than full-size monoclonal antibodies (mAbs) and have a number of advantages for biotechnological applications, such as small size, high specificity, solubility, stability, and great refolding capacity. Carcinoembryonic antigen (CEA) is a tumor-associated glycoprotein expressed in a variety of cancers. Detection of CEA on the tumor cell surface may be carried out using anti-CEA antibodies and conventional fluorescent dyes. Semiconductor quantum dots (QDs) are brighter and more photostable than organic dyes; they provide the possibility for labeling of different recognition molecules with QDs of different colors but excitable with the same wavelength of excitation. In this study, the abilities for specific detection of CEA expressed by tumor cells with anti-CEA sdAbs biotinylated in vitro and in vivo, as well as with anti-CEA mAbs biotinylated in vitro, were compared using flow cytometry and the conjugates of streptavidin with QDs (SA-QDs). The results demonstrated that either in vitro or in vivo biotinylated anti-CEA sdAbs are more sensitive for cell staining compared to biotinylated anti-CEA mAbs. The data also show that simultaneous use of biotinylated sdAbs with highly fluorescent SA-QDs can considerably improve the sensitivity of detection of CEA on tumor cell surfaces. 相似文献
963.
964.
Jixun Luo Regina Ahmed Behjat Kosar-Hashemi Oscar Larroque Vito M. Butardo Jr. Greg J. Tanner Michelle L. Colgrave Narayana M. Upadhyaya Ian J. Tetlow Michael J. Emes Anthony Millar Stephen A. Jobling Matthew K. Morell Zhongyi Li 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2015,128(7):1407-1419
965.
Mariana Concei??o Souza Tatiana Almeida Padua Natalia Domingos Torres Maria Fernanda de Souza Costa Victor Facchinetti Claudia Regina Brand?o Gomes Marcus Vinícius Nora Souza Maria das Gra?as Henriques 《Memórias do Instituto Oswaldo Cruz》2015,110(4):560-565
A rapid decrease in parasitaemia remains the major goal for new antimalarial drugs
and thus, in vivo models must provide precise results concerning parasitaemia
modulation. Hydroxyethylamine comprise an important group of alkanolamine compounds
that exhibit pharmacological properties as proteases inhibitors that has already been
proposed as a new class of antimalarial drugs. Herein, it was tested the antimalarial
property of new nine different hydroxyethylamine derivatives using the green
fluorescent protein (GFP)-expressing Plasmodium berghei strain. By
comparing flow cytometry and microscopic analysis to evaluate parasitaemia
recrudescence, it was observed that flow cytometry was a more sensitive methodology.
The nine hydroxyethylamine derivatives were obtained by inserting one of the
following radical in the para position: H, 4Cl, 4-Br, 4-F, 4-CH3,
4-OCH3, 4-NO2, 4-NH2 and 3-Br. The antimalarial test showed that the compound that
received the methyl group (4-CH3) inhibited 70% of parasite growth. Our results
suggest that GFP-transfected P. berghei is a useful tool to study the recrudescence
of novel antimalarial drugs through parasitaemia examination by flow cytometry.
Furthermore, it was demonstrated that the insertion of a methyl group at the
para position of the sulfonamide ring appears to be critical for
the antimalarial activity of this class of compounds. 相似文献
966.
Jaqueline Dario Capobiango Sthefany Pagliari Aline Kuhn Sbruzzi Pasquali Beatriz Nino Fernanda Pinto Ferreira Thaís Cabral Monica Nely Norder Tschurtschenthaler Italmar Teodorico Navarro Jo?o Luis Garcia Regina Mitsuka-Breganó Edna Maria Vissoci Reiche 《Memórias do Instituto Oswaldo Cruz》2015,110(6):732-738
The aim of this study was to evaluate an enzyme-linked immunoassay with recombinant
rhoptry protein 2 (ELISA-rROP2) for its ability to detectToxoplasma
gondii ROP2-specific IgG in samples from pregnant women. The study
included 236 samples that were divided into groups according to serological screening
profiles for toxoplasmosis: unexposed (n = 65), probable acute infection (n = 48),
possible acute infection (n = 58) and exposed to the parasite (n = 65). When an
indirect immunofluorescence assay forT. gondii-specific IgG was
considered as a reference test, the ELISA-rROP2 had a sensitivity of 61.8%,
specificity of 62.8%, predictive positive value of 76.6% and predictive negative
value of 45.4% (p = 0.0002). The ELISA-rROP2 reacted with 62.5% of the samples from
pregnant women with probable acute infection and 40% of the samples from pregnant
women with previous exposure (p = 0.0180). Seropositivity was observed in 50/57
(87.7%) pregnant women with possible infection. The results underscored that
T. gondii rROP2 is recognised by specific IgG antibodies in both
the acute and chronic phases of toxoplasmosis acquired during pregnancy. However, the
sensitivity of the ELISA-rROP2 was higher in the pregnant women with probable and
possible acute infections and IgM reactivity. 相似文献
967.
Paula Pierozan Fernanda Ferreira Bárbara Ortiz de Lima Carolina Gonçalves Fernandes Priscila Totarelli Monteforte Natalia de Castro Medaglia Claudia Bincoletto Soraya Soubhi Smaili Regina Pessoa-Pureur 《Experimental cell research》2014
Quinolinic acid (QUIN) is a glutamate agonist which markedly enhances the vulnerability of neural cells to excitotoxicity. QUIN is produced from the amino acid tryptophan through the kynurenine pathway (KP). Dysregulation of this pathway is associated with neurodegenerative conditions. In this study we treated striatal astrocytes in culture with QUIN and assayed the endogenous phosphorylating system associated with glial fibrillary acidic protein (GFAP) and vimentin as well as cytoskeletal remodeling. After 24 h incubation with 100 µM QUIN, cells were exposed to 32P-orthophosphate and/or protein kinase A (PKA), protein kinase dependent of Ca2+/calmodulin II (PKCaMII) or protein kinase C (PKC) inhibitors, H89 (20 μM), KN93 (10 μM) and staurosporin (10 nM), respectively. Results showed that hyperphosphorylation was abrogated by PKA and PKC inhibitors but not by the PKCaMII inhibitor. The specific antagonists to ionotropic NMDA and non-NMDA (50 µM DL-AP5 and CNQX, respectively) glutamate receptors as well as to metabotropic glutamate receptor (mGLUR; 50 µM MCPG), mGLUR1 (100 µM MPEP) and mGLUR5 (10 µM 4C3HPG) prevented the hyperphosphorylation provoked by QUIN. Also, intra and extracellular Ca2+ quelators (1 mM EGTA; 10 µM BAPTA-AM, respectively) prevented QUIN-mediated effect, while Ca2+ influx through voltage-dependent Ca2+ channel type L (L-VDCC) (blocker: 10 µM verapamil) is not implicated in this effect. Morphological analysis showed dramatically altered actin cytoskeleton with concomitant change of morphology to fusiform and/or flattened cells with retracted cytoplasm and disruption of the GFAP meshwork, supporting misregulation of actin cytoskeleton. Both hyperphosphorylation and cytoskeletal remodeling were reversed 24 h after QUIN removal. Astrocytes are highly plastic cells and the vulnerability of astrocyte cytoskeleton may have important implications for understanding the neurotoxicity of QUIN in neurodegenerative disorders. 相似文献
968.
Carola Stribl Aladin Samara Dietrich Trümbach Regina Peis Manuela Neumann Helmut Fuchs Valerie Gailus-Durner Martin Hrabě de Angelis Birgit Rathkolb Eckhard Wolf Johannes Beckers Marion Horsch Frauke Neff Elisabeth Kremmer Sebastian Koob Andreas S. Reichert Wolfgang Hans Jan Rozman Martin Klingenspor Michaela Aichler Axel Karl Walch Lore Becker Thomas Klopstock Lisa Glasl Sabine M. H?lter Wolfgang Wurst Thomas Floss 《The Journal of biological chemistry》2014,289(15):10769-10784
The majority of amyotrophic lateral sclerosis (ALS) cases as well as many patients suffering from frontotemporal lobar dementia (FTLD) with ubiquitinated inclusion bodies show TDP-43 pathology, the protein encoded by the TAR DNA-binding protein (Tardbp) gene. We used recombinase-mediated cassette exchange to introduce an ALS patient cDNA into the mouse Tdp-43 locus. Expression levels of human A315T TDP-43 protein were 300% elevated in heterozygotes, whereas the endogenous mouse Tdp-43 was decreased to 20% of wild type levels as a result of disturbed feedback regulation. Heterozygous TDP-43A315TKi mutants lost 10% of their body weight and developed insoluble TDP-43 protein starting as early as 3 months after birth, a pathology that was exacerbated with age. We analyzed the splicing patterns of known Tdp-43 target genes as well as genome-wide gene expression levels in different tissues that indicated mitochondrial dysfunction. In heterozygous mutant animals, we observed a relative decrease in expression of Parkin (Park2) and the fatty acid transporter CD36 along with an increase in fatty acids, HDL cholesterol, and glucose in the blood. As seen in transmission electron microscopy, neuronal cells in motor cortices of TDP-43A315TKi animals had abnormal neuronal mitochondrial cristae formation. Motor neurons were reduced to 90%, but only slight motoric impairment was detected. The observed phenotype was interpreted as a predisease model, which might be valuable for the identification of further environmental or genetic triggers of neurodegeneration. 相似文献
969.
Martha Elba Gonzalez-Mejia Enrique Torres-Rasgado Leonardo M Porchia Hilda Rosas Salgado José-Luis Totolhua Arturo Ortega Luisa Clara Regina Hernández-Kelly Guadalupe Ruiz-Vivanco Blanca G Báez-Duarte Ricardo Pérez-Fuentes 《Memórias do Instituto Oswaldo Cruz》2014,109(2):174-181
Chagas disease, caused by Trypanosoma cruzi, represents an endemic
among Latin America countries. The participation of free radicals, especially nitric
oxide (NO), has been demonstrated in the pathophysiology of seropositive individuals
with T. cruzi. In Chagas disease, increased NO contributes to the
development of cardiomyopathy and megacolon. Metallothioneins (MTs) are efficient
free radicals scavengers of NO in vitro and in vivo. Here, we developed a murine
model of the chronic phase of Chagas disease using endemic T. cruzi
RyCH1 in BALB/c mice, which were divided into four groups: infected non-treated
(Inf), infected N-monomethyl-L-arginine treated (Inf L-NAME), non-infected L-NAME
treated and non-infected vehicle-treated. We determined blood parasitaemia and NO
levels, the extent of parasite nests in tissues and liver MT-I expression levels. It
was observed that NO levels were increasing in Inf mice in a time-dependent manner.
Inf L-NAME mice had fewer T. cruzi nests in cardiac and skeletal
muscle with decreased blood NO levels at day 135 post infection. This affect was
negatively correlated with an increase of MT-I expression (r = -0.8462, p <
0.0001). In conclusion, we determined that in Chagas disease, an unknown inhibitory
mechanism reduces MT-I expression, allowing augmented NO levels. 相似文献
970.
Sérgio Ricardo Fernandes Araújo Sarra Elisabeth Jamieson Kathryn Margaret Dupnik Glória Regina Monteiro Maurício Lisboa Nobre Márcia Sousa Dias Pedro Bezerra Trindade Neto Maria do Carmo Palmeira Queiroz Carlos Eduardo Maia Gomes Jenefer Mary Blackwell Selma Maria Bezerra Jeronimo 《Memórias do Instituto Oswaldo Cruz》2014,109(2):182-188
Leprosy remains prevalent in Brazil. ErbB2 is a receptor for leprosy bacilli entering
Schwann cells, which mediates Mycobacterium leprae-induced
demyelination and the ERBB2 gene lies within a leprosy
susceptibility locus on chromosome 17q11-q21. To determine whether
polymorphisms at the ERBB2 locus contribute to this linkage peak,
three haplotype tagging single nucleotide polymorphisms (tag-SNPs) (rs2517956,
rs2952156, rs1058808) were genotyped in 72 families (208 cases; 372 individuals) from
the state of Pará (PA). All three tag-SNPs were associated with leprosy per se [best
SNP rs2517959 odds ratio (OR) = 2.22; 95% confidence interval (CI) 1.37-3.59; p =
0.001]. Lepromatous (LL) (OR = 3.25; 95% CI 1.37-7.70; p = 0.007) and tuberculoid
(TT) (OR = 1.79; 95% CI 1.04-3.05; p = 0.034) leprosy both contributed to the
association, which is consistent with the previous linkage to chromosome 17q11-q21 in
the population from PA and supports the functional role of ErbB2 in disease
pathogenesis. To attempt to replicate these findings, six SNPs (rs2517955, rs2517956,
rs1810132, rs2952156, rs1801200, rs1058808) were genotyped in a population-based
sample of 570 leprosy cases and 370 controls from the state of Rio Grande do Norte
(RN) and the results were analysed using logistic regression analysis. However, none
of the associations were replicated in the RN sample, whether analysed for leprosy
per se, LL leprosy, TT leprosy, erythema nodosum leprosum or reversal reaction
conditions. The role of polymorphisms at ERBB2 in controlling
susceptibility to leprosy in Brazil therefore remains unclear. 相似文献