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91.
We examined whether periparturient dairy cattle shed Cryptosporidium parvum oocysts within 12 hr of calving on 3 commercial dairy farms endemic for calfhood cryptosporidiosis. Using a diagnostic method that can detect as few as 1 oocyst per gram of feces, we found no evidence of C. parvum oocysts in 86 fecal samples collected within 12 hr of calving from 43 dairy cows. 相似文献
92.
Paula Zaghetto Almeida Josana Maria Messias Marita Gimenez Pereira Vanessa Elisa Pinheiro Lummy Maria Oliveira Monteiro Paulo Ricardo Heinen 《Biocatalysis and Biotransformation》2018,36(5):389-395
Starch has great importance in human diet, since it is a heteropolymer of plants, mainly found in roots, as potato, cassava and arrowroots. This carbohydrate is composed by a highly-branched chain: amylopectin; and a linear chain: amylose. The proportion between the chains varies according to the botanical source. Starch hydrolysis is catalyzed by enzymes of the amilolytic system, named amylases. Among the various enzymes of this system, the glucoamylases (EC 3.2.1.3 glucan 1,4-alpha-glucosidases) are the majority because they hydrolyze the glycosidic linkages at the end of starch chains releasing glucose monomers. In this work, a glucoamylase secreted in the culture medium, by the ascomycete Aspergillus brasiliensis, was immobilized in Dietilaminoetil Sepharose-Polyethylene Glycol (DEAE-PEG), since immobilized biocatalysts are more stable in long periods of hydrolysis, and can be recovered from the final product and reused for several cycles. Glucoamylase immobilization has shown great thermal stability improvement over the soluble enzyme, reaching 66% more activity after 6?h at 60?°C, and 68% of the activity after 10 hydrolysis cycles. A simplex centroid experimental mixture design was applied as a tool to characterize the affinity of the immobilized enzyme for different starchy substrates. In assays containing several proportions of amylose, amylopectin and starch, the glucoamylase from A. brasiliensis mainly hydrolyzed the amylopectin chains, showing to have preference by branched substrates. 相似文献
93.
Comparative proteomic analysis of Xanthomonas citri ssp. citri periplasmic proteins reveals changes in cellular envelope metabolism during in vitro pathogenicity induction 下载免费PDF全文
Juliana Artier Flávia da Silva Zandonadi Flávia Maria de Souza Carvalho Bianca Alves Pauletti Adriana Franco Paes Leme Carolina Moretto Carnielli Heloisa Sobreiro Selistre‐de‐Araujo Maria Célia Bertolini Jesus Aparecido Ferro José Belasque Júnior Julio Cezar Franco de Oliveira Maria Teresa Marques Novo‐Mansur 《Molecular Plant Pathology》2018,19(1):143-157
Citrus canker is a plant disease caused by Gram‐negative bacteria from the genus Xanthomonas. The most virulent species is Xanthomonas citri ssp. citri (XAC), which attacks a wide range of citrus hosts. Differential proteomic analysis of the periplasm‐enriched fraction was performed for XAC cells grown in pathogenicity‐inducing (XAM‐M) and pathogenicity‐non‐inducing (nutrient broth) media using two‐dimensional electrophoresis combined with liquid chromatography‐tandem mass spectrometry. Amongst the 40 proteins identified, transglycosylase was detected in a highly abundant spot in XAC cells grown under inducing condition. Additional up‐regulated proteins related to cellular envelope metabolism included glucose‐1‐phosphate thymidylyltransferase, dTDP‐4‐dehydrorhamnose‐3,5‐epimerase and peptidyl‐prolyl cis–trans‐isomerase. Phosphoglucomutase and superoxide dismutase proteins, known to be involved in pathogenicity in other Xanthomonas species or organisms, were also detected. Western blot and quantitative real‐time polymerase chain reaction analyses for transglycosylase and superoxide dismutase confirmed that these proteins were up‐regulated under inducing condition, consistent with the proteomic results. Multiple spots for the 60‐kDa chaperonin and glyceraldehyde‐3‐phosphate dehydrogenase were identified, suggesting the presence of post‐translational modifications. We propose that substantial alterations in cellular envelope metabolism occur during the XAC infectious process, which are related to several aspects, from defence against reactive oxygen species to exopolysaccharide synthesis. Our results provide new candidates for virulence‐related proteins, whose abundance correlates with the induction of pathogenicity and virulence genes, such as hrpD6, hrpG, hrpB7, hpa1 and hrpX. The results present new potential targets against XAC to be investigated in further functional studies. 相似文献
94.
Janaine Almeida Neto Daniel Amando Nery Katia Simoni Bezerra Lima Maria Eduarda Gomes da Cruz Silva Tarcísio Cícero de Lima Araújo Nathália Andrezza Carvalho de Souza Rodolfo Hideki Vicente Nishimura Camila de Souza Araújo Ana Paula de Oliveira Jackson Roberto Guedes da Silva Almeida Larissa Araújo Rolim 《化学与生物多样性》2023,20(3):e202201039
This article describes the phytochemical study of Cannabis sativa roots from northeastern Brazil. The dried plant material was pulverized and subjected to exhaustive maceration with ethanol at room temperature, obtaining the crude ethanolic extract (Cs-EEBR). The volatile compounds were analyzed by gas chromatography coupled with mass spectrometry (GC/MS), which allowed to identify 22 compounds by comparing the linear retention index (LRI), the similarity index (SI) and the fragmentation pattern of the constituents with the literature. By this technique the major compounds identified were: friedelan-3-one and β-sitosterol. In addition, two fractions were obtained from Cs-EEBR by classical column chromatography and preparative thin layer chromatography. These fractions were analyzed by NMR and IR and together with the mass spectrometry data allowed to identify the compounds: epifriedelanol, friedelan-3-one, β-sitosterol and stigmasterol. The study contributed to the phytochemical knowledge of Cannabis sativa, specifically the roots, as there are few reports on the chemical constituents of this part of the plant. 相似文献
95.
Llis A. Carlos‐Júnior Matthew Spencer Danilo Mesquita Neves Timothy Peter Moulton Dbora de Oliveira Pires Clovis Barreira e Castro Carlos Renato Rezende Ventura Carlos Eduardo Leite Ferreira Cristiana Silveira Serejo Simone Oigman‐Pszczol Fernanda Araújo Casares Marcelo Checoli Mantelatto Joel Christopher Creed 《Diversity & distributions》2019,25(5):743-757
96.
Nogueira-Ferreira Rita Ferreira Rita Padrão Ana Isabel Oliveira Paula Santos Manuel Kavazis Andreas N. Vitorino Rui Moreira-Gonçalves Daniel 《Journal of physiology and biochemistry》2019,75(4):561-572
Journal of Physiology and Biochemistry - Aerobic exercise training induces a unique cardioprotective phenotype, but it is becoming clear that it does not promote the same structural, functional,... 相似文献
97.
Daniella Braz Parente Fernando Fernandes Paiva Jaime Araújo Oliveira Neto Lilian Machado-Silva Fatima Aparecida Ferreira Figueiredo Valeria Lanzoni Carlos Frederico Ferreira Campos Pedro Emmanuel Alvarenga Americano do Brasil Marilia de Brito Gomes Renata de Mello Perez Rosana Souza Rodrigues 《PloS one》2015,10(5)
ObjectiveTo evaluate the capability of intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) to assess steatohepatitis and fibrosis determined by histopathology in type 2 diabetic patients.MethodsFifty-nine type 2 diabetic patients (49 women, 10 men; mean age, 54 ± 9 years) were submitted to liver biopsy for the evaluation of non-alcoholic fatty liver disease (NAFLD) and underwent DWI on a 3.0T MR system using 10 b values. Institutional approval and patient consent were obtained. Pure molecular-based (D), perfusion-related (D*), and vascular fraction (f) were calculated using a double exponential model and least squares curve fitting. D, D*, and f were compared between patients with and without steatohepatitis and between patients with and without fibrosis. The variables were compared by using the Ranksum test and Student t-test.ResultsSteatohepatitis was observed in 22 patients and fibrosis in 16 patients. A lower D median (0.70 s/mm2 vs. 0.83 s/mm2, p<0.05) and a lower D* median (34.39 s/mm2 vs. 45.23 s/mm2, p<0.05) were observed among those with steatohepatitis. A lower D median (0.70 s/mm2 vs. 0.82 s/mm2, p<0.05) and a lower D* median (35.01 s/mm2 vs. 44.76 s/mm2, p=0.05) were also observed among those with fibrosis.ConclusionIVIM-DWI has the potential to aid in the characterization of steatohepatitis and fibrosis. 相似文献
98.
99.
The denitrification performance of a lab-scale anoxic rotating biological contactor (RBC) using landfill leachate with high
nitrate concentration was evaluated. Under a carbon to nitrogen ratio (C/N) of 2, the reactor achieved N-NO3
− removal efficiencies above 95% for concentrations up to 100 mg N-NO3
− l−1. The highest observed denitrification rate was 55 mg N-NO3
− l−1 h−1 (15 g N-NO3
− m−2 d−1) at a nitrate concentration of 560 mg N-NO3
− l−1. Although the reactor has revealed a very good performance in terms of denitrification, effluent chemical oxygen demand (COD)
concentrations were still high for direct discharge. The results obtained in a subsequent experiment at constant nitrate concentration
(220 mg N-NO3
− l−1) and lower C/N ratios (1.2 and 1.5) evidenced that the organic matter present in the leachate was non-biodegradable. A phosphorus
concentration of 10 mg P-PO4
3− l−1 promoted autotrophic denitrification, revealing the importance of phosphorus concentration on biological denitrification
processes. 相似文献
100.
Clonal diversity and conservation genetics of the medicinal plant Carapichea ipecacuanha (Rubiaceae)
de Oliveira LO Venturini BA Rossi AA Hastenreiter SS 《Genetics and molecular biology》2010,33(1):86-93
The roots of the understorey shrub Carapichea ipecacuanha (ipecac) have medicinal properties, and the uprooting of wild plants has supplied most of the world demand for this species. Although under severe population decline, C. ipecacuanha lacks legal protection. In the wild, the aerial stems of ipecac clump together to form clusters with well-defined borders. Cluster size may range from several to hundreds of aerial stems. To investigate the extent of clonality among aerial stems in ipecac clusters, we sampled 50 wild clusters (a total of 291 aerial stems) and screened them with 89 inter-simple sequence repeat (ISSR) markers. The 291 aerial stems were grouped into 42 putative clones. The clonal groups generally consisted of aerial stems from the same cluster, and there was little or no genetic differentiation among aerial stems at the cluster level. These findings suggest that strategies designed to conserve ipecac in situ should not rely upon census data, which are based on the number of aerial stems per cluster and the number of clusters per population, because such data greatly underestimate the species effective population size and genetic diversity. Our results also indicate that this species needs protection at a federal level. 相似文献