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131.
de Oliveira RM Lia EN Guimarães RM Bocca AL Cavalcante Neto FF da Silva TA 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》2008,30(2):113-118
OBJECTIVE: To analyze cytomorphologically the buccal mucosa of patients with Alzheimer's disease (AD). STUDY DESIGN: Brush biopsies were obtained from 10 patients with AD and 9 age-matched controls without neurologic symptoms from 3 distinct oral sites. RESULTS: A significant reduction in partially keratinized intermediate (red) cells was observed in the buccal mucosa of the AD group. In the AD group, parabasal cells from the floor of the mouth (p = 0.017) and buccal mucosa (p = 0.058) and red cells,from the tongue dorsum (p = 0.013) and buccal mucosa (p = 0.002), exhibited significantly greater nuclear areas. With regard to the nuclear to cytoplasmic (N:C) ratio, intermediate (red) cells from the buccal mucosa and tongue dorsum of AD individuals showed a decrease in this parameter (p <0.0001), while superficial (yellow) cells (from buccal mucosa) (p= 0.042) and parabasal (blue) cells (from the tongue dorsum) (p = 0.003) exhibited an increased N:C ratio. No significant differences were detected in the cells from the floor of the mouth. CONCLUSIONS: Our findings indicate that cytologic and cytometric changes were detectable in the exfoliative cytology of the buccal mucosa and tongue in the AD group. 相似文献
132.
Kátia Aparecida Kern Erica Marusa Pergo Fernanda Lima Kagami Luis Saraiva Arraes Maria Aparecida Sert Emy Luiza Ishii-Iwamoto 《Plant Physiology and Biochemistry》2009,47(11-12):1095-1101
This study investigated the effects of exogenously applied ethanol on Euphorbia heterophylla L., a troublesome weed in field and plantation crops. Ethanol at concentrations ranging from 0.25 to 1.5% caused a dose-dependent inhibition of germination and growth of E. heterophylla. Measurements of respiratory activity and alcohol dehydrogenase (E.C. 1.1.1.1) activity during seed imbibition and initial seedling growth revealed that ethanol induces a prolongation of hypoxic conditions in the growing tissues. In isolated mitochondria, ethanol inhibited the respiration coupled to ADP phosphorylation, an action that probably contributed to modifications observed in the respiratory activity of embryos. A comparison of the effects of methanol, ethanol, propanol and acetaldehyde on germination and growth of E. heterophylla indicates that alcohol dehydrogenase activity is required for the observed effects, with the conversion of ethanol to acetaldehyde playing a role in the ethanol-induced injuries. 相似文献
133.
Lucinéia de Fátima Chasko Ribeiro Rose Meire Costa Brancalhão Ednéia Fátima Brambilla Torquato Maria Aparecida Fernandez 《Journal of invertebrate pathology》2009,100(3):195-198
Bombyx mori entomopathogenic virus infection is a serious problem for silk production in tropical regions. Here, we investigate the susceptibility of the B. mori cardia epithelial cells to B. mori Nucleopolyhedrovirus, BmMNPV. Results show that cardia cells are susceptible to BmMNPV and that the cytopathology is similar to that in other target cells. The infection was detected at 6 day post-inoculation. This infection time, together with the protected cover intima, suggests that the cardia region is a secondary target, infected by budded virus. 相似文献
134.
Fabrícia Gimenes Mariana Aprígio Assis Adriana Fiorini Vânia Aparecida Mareze Nadia Monesi Maria Aparecida Fernandez 《Molecular genetics and genomics : MGG》2009,281(5):539-549
Bent DNA sites promote the curvature of DNA in both eukaryotic and prokaryotic chromosomes. Here, we investigate the localization
and structure of intrinsically bent DNA sites in the extensively characterized Drosophila melanogaster third chromosome DAFC-66D segment (Drosophila amplicon
in the follicle cells). This region contains the amplification control element ACE3, which is a replication enhancer that acts in cis to activate the major replication origin ori-β. Through both electrophoretic and in silico analysis, we have identified three major bent DNA sites in DAFC-66D. The bent DNA site (b1) is localized in the ACE3 element, whereas the other two bent DNA sites (b2 and b3) are localized in the ori-β region. Four additional bent DNA sites were identified in the intron of the S18 gene and near the TATA box of the S15, S19, and S16 genes. The identification of DNA bent sites in genomic regions previously characterized as functionally relevant for DNA
amplification further supports a function for DNA bent sites in DNA replication in eukaryotes.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
135.
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
136.
Aparecida Resende F de Andrade Barcala CA da Silva Faria MC Kato FH Cunha WR Tavares DC 《Life sciences》2006,79(13):1268-1273
Ursolic acid (UA) and oleanolic acid (OA) are triterpenoid compounds found in food, medicinal herbs and various other plants in free form or bound to glycosides. Both substances are known for their antimicrobial, hepatoprotective, anti-inflammatory, antiallergic, antiviral and cytotoxic activities. In the present study, we evaluated the antimutagenic potential of UA and OA using the micronucleus test in peripheral blood and bone marrow of Balb/c mice. The animals were divided into 10 treatment groups: mice treated with UA (80 mg/kg b.w.); OA (80 mg/kg b.w.); a mixture of UA and OA (80 mg/kg b.w.); the antineoplastic agent doxorubicin (DXR, 90 mg/kg b.w.); DMSO and DXR; UA and DXR; OA and DXR; UA, OA and DXR, and negative and solvent controls. UA, OA and a mixture of UA and OA were administered to the animals by gavage, followed by the intraperitoneal injection of DXR. The results showed a significant reduction in micronucleus frequency in the groups concomitantly treated with the triterpenoid compounds and DXR compared to that treated with DXR alone. The present results demonstrate the antimutagenic activity of UA and OA under the experimental conditions used in this study. 相似文献
137.
Aila Riany de Brito Nadabe dos Santos Reis Tatielle Pereira Silva Renata Cristina Ferreira Bonomo Ana Paula Trovatti Uetanabaro Sandra Aparecida de Assis 《Preparative biochemistry & biotechnology》2017,47(10):977-985
Endoglucanase production by Aspergillus oryzae ATCC 10124 cultivated in rice husks or peanut shells was optimized by experimental design as a function of humidity, time, and temperature. The optimum temperature for the endoglucanase activity was estimated by a univariate analysis (one factor at the time) as 50°C (rice husks) and 60°C (peanut shells), however, by a multivariate analysis (synergism of factors), it was determined a different temperature (56°C) for endoglucanase from peanut shells. For the optimum pH, values determined by univariate and multivariate analysis were 5 and 5.2 (rice husk) and 5 and 7.6 (peanut shells). In addition, the best half-lives were observed at 50°C as 22.8?hr (rice husks) and 7.3?hr (peanut shells), also, 80% of residual activities was obtained between 30 and 50°C for both substrates, and the pH stability was improved at 5–7 (rice hulls) and 6–9 (peanut shells). Both endoglucanases obtained presented different characteristics as a result of the versatility of fungi in different substrates. 相似文献
138.
Fernanda Aparecida Nieri-Bastos Marcos Gomes Lopes Paulo Henrique Duarte Can?ado Giselle Ayres Razera Rossa Jo?o Luiz Horácio Faccini Solange Maria Gennari Marcelo Bahia Labruna 《Memórias do Instituto Oswaldo Cruz》2014,109(2):259-261
Adult ticks of the species Amblyomma parvum were collected from the
vegetation in the Pantanal biome (state of Mato Grosso do Sul) and from horses in the
Cerrado biome (state of Piauí) in Brazil. The ticks were
individually tested for rickettsial infection via polymerase chain reaction (PCR)
targeting three rickettsial genes, gltA, ompA and
ompB. Overall, 63.5% (40/63) and 66.7% (2/3) of A.
parvum ticks from Pantanal and Cerrado, respectively, contained
rickettsial DNA, which were all confirmed by DNA sequencing to be 100% identical to
the corresponding fragments of the gltA, ompA and
ompB genes of Candidatus Rickettsia andeanae.
This report is the first to describe Ca. R. andeanae in Brazil. 相似文献
139.
Aline Garcia Kozlowski Megmar Aparecida dos Santos Carneiro Márcia Alves Dias de Matos Sheila Araújo Teles Jo?o Alves Araújo Filho Koko Otsuki Ana Carolina Paulo Vicente Regina Maria Bringel Martins 《Memórias do Instituto Oswaldo Cruz》2014,109(1):118-121
Human T-cell lymphotropic virus (HTLV) may impact the clinical course of tuberculosis
(TB). Both infections are highly endemic in Brazil. The aim of this study was to
assess the prevalence of HTLV-1/2 in TB patients in Central-West Brazil and to
perform a genetic characterisation of the respective isolates. Of the 402 patients,
six (1.49%) were positive for anti-HTLV and five (1.24%; 95% confidence interval:
0.46-3.05) were infected with HTLV-1/2. Genetic characterisation demonstrated that
the four HTLV-1 isolates belonged to the Transcontinental subgroup A of the
Cosmopolitan subtype a and that the HTLV-2 isolate belonged to subtype a (HTLV-2a/c).
The prevalence of HTLV infection observed in this study is higher than that observed
in local blood donors and the HTLV-1 and 2 subtypes identified are consistent with
those circulating in Brazil. 相似文献
140.