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91.
Extract of Vernonia condensata (Asteraceae = Compositae) leaves has different uses in Brazilian folk medicine, which includes analgesic and antiinflamatory agent. The aim of this study was to apply a modified simplex-centroid mixture design to evaluate the best extractor system for the antinociceptive activity, evaluated by writhing test. Different solvents (acetone, dichloromethane, ethanol and ethyl acetate) as well as their binary, ternary and quaternary mixtures were used. For comparison, aqueous extract was also evaluated. LD50 was estimated and qualitative phytochemical screening, conducted. The extracts with antinociceptive activity were: aqueous, acetone, dicloromethane (DCM), ethanol (ETOH), acetone-DCM, acetone-ETOH, acetone-ethyl acetate, ETOH-ethyl acetate, acetone-DCM-ethyl acetate, acetone-ETOH-ethyl acetate and DCM-ETOH-ethyl acetate. The higher margin of safety (LD50/ED50) was for acetone > acetone-ETOH-ethyl acetate > aqueous > ETOH = acetone-ETOH > DCM > acetone-ethyl acetate > DCM-ETOH-ethyl acetate > acetone-DCM > acetone-DCM-ethyl acetate. Phytochemical screening showed that all the extracts contained alkaloids, phenolic compounds, flavonoids, tannins and saponins. In conclusion, the extractor system influences both the pharmacological activity and acute toxicity of leaves from V. condensata. Acetone and the ternary mixture, acetone-ETOH-ethyl acetate extracts showed higher margin of safety than aqueous extract. 相似文献
92.
Tiago Collares Vinicius Farias Campos Fabiana Kömmling Seixas Paulo V. Cavalcanti Odir A. Dellagostin Heden Luiz M. Moreira João Carlos Deschamps 《Journal of biosciences》2010,35(1):39-47
The silver catfish (Rhamdia quelen) is an endemic American fish species. The sperm of each species has its own peculiarities and biological characteristics,
which influence the success of mass DNA transfer methods. Our objective in this study was to evaluate different sperm-mediated
gene transfer (SMGT) methods to obtain transgenic silver catfish. Different treatments for the incorporation of a foreign
pEGFP plasmid group were used: (1) dehydrated/rehydrated (DR), (2) dehydrated/rehydrated/electroporated (DRE), (3) electroporated
(E), (4) incubated with seminal plasma (INC); and (5) incubated in the absence of seminal plasma (INCSP). Sperm motility,
time of activity duration (TAD), fertilization rate (FR), hatching rate (HR) and sperm morphology were also evaluated. The
polymerase chain reaction (PCR) positivity rates for the presence of the transgene were: DRE 60%; DR 40%; E 25%; INC 5% and
INCSP 25%. The rates of embryo EGFP expression were: DRE 63%; DR 44%; E 34%; INC 8% and INCSP 38%. The fertilization rate
in the control and DRE treatments groups were higher than in the DR group, but the E, INC and INCSP treatment groups had the
lowest rate. The hatching rates of the DRE, DR and control groups were higher than in the INCSP, INC and E treatment groups
(P>0.05). There were no differences among the DRE and DR, E and DR, E and INCSP groups in expression and PCR positivity rates
of enhanced green fluorescent protein (EGFP) in embryos. Scanning electron microscopy also did not show any change in sperm
morphology among treatment groups. To the best of our knowledge, this is the first report on transgene transmission of exogenous
DNA into silver catfish larvae through SMGT technology. 相似文献
93.
Costa-Filho A Souza ML Martins RC dos Santos AV Silva GV Comaru MW Moreira MF Atella GC Allodi S Nasciutti LE Masuda H Silva LC 《Insect biochemistry and molecular biology》2004,34(3):251-260
We have previously characterized heparan sulfate (HS) as the major ovarian sulfated glycosaminoglycan (GAG) in females of Rhodnius prolixus, while chondroitin sulfate (CS) was the minor component. Using histochemical procedures we found that GAGs were concentrated in the ovarian tissue but not found inside the oocytes. Here, we extend our initial observations of GAG expression in R. prolixus by characterizing these molecules in other organs: the fat body, intestinal tract, and the reproductive tracts. Only HS and CS were found in the three organs analyzed, however CS was the major GAG species in these tissues. We also determined the compartmental distribution of GAGs in these organs by histochemical analysis using 1,9-dimethylmethylene blue, and evaluated the specific distribution of CS within both male and female reproductive tracts by immunohistochemistry using an anti-CS antibody. We also determined the GAG composition in eggs at days 0 and 6 of embryonic development. Only HS and CS were found in eggs at day 6, while no sulfated GAGs were detected at day 0. Our results demonstrate that HS and CS are the only sulfated GAG species expressed in the fat body and in the intestinal and reproductive tracts of Rhodnius male and female adults. Both sulfated GAGs were also identified in Rhodnius embryos. Altogether, these results show no qualitative differences in the sulfated GAG composition regarding tissue-specific or development-specific distribution. 相似文献
94.
Alex?MiraEmail author Ravindra?Pushker Boris?A?Legault David?Moreira Francisco?Rodríguez-Valera 《BMC evolutionary biology》2004,4(1):50
Background
The phylogenetic position and evolutionary relationships of Fusobacteria remain uncertain. Especially intriguing is their relatedness to low G+C Gram positive bacteria (Firmicutes) by ribosomal molecular phylogenies, but their possession of a typical gram negative outer membrane. Taking advantage of the recent completion of the Fusobacterium nucleatum genome sequence we have examined the evolutionary relationships of Fusobacterium genes by phylogenetic analysis and comparative genomics tools. 相似文献95.
In this paper it is described for the first time the capability of Myrothecium verrucaria to grow in submerged and solid state cultures using poultry feathers as the only substrate. The fungus produced a protease
with an unusual keratinolytic activity among plant pathogenic fungi. Its crude protease hydrolyzed keratinous substrates at
pH 9.0 and 40 °C in the following order: poultry feather keratin > sheep wool keratin > human nail keratin > human hair keratin.
Protease activity was highly sensitive to phenylmethyl sulphonyl fluoride (PMSF) indicating that the enzyme belonged to the
serine protease family. 相似文献
96.
Valente C Moreira R Guedes RC Iley J Jaffar M Douglas KT 《Bioorganic & medicinal chemistry》2007,15(15):5340-5350
A series of 1,4-naphthoquinone derivatives diversely substituted at C-2, C-3, C-5 and C-8, prepared by reaction of amines, amino acids and alcohols with commercial 1,4-naphthoquinones, has been evaluated against papain and bovine spleen cathepsin B. These 1,4-naphthoquinone derivatives were found to be irreversible inhibitors for both cysteine proteases, with second-order rate constants, k(2), ranging from 0.67 to 35.4M(-1)s(-1) for papain, and from 0.54 to 8.03M(-1)s(-1) for cathepsin B. Some derivatives display a hyperbolic dependence of the first-order inactivation rate constant, k(obs), with the inhibitor concentration, indicative of a specific interaction process between enzyme and inhibitor. The chemical reactivity of the compounds towards cysteine as a model thiol is dependent on the naphthoquinone LUMO energy, whereas papain inactivation is not. The 1,4-naphthoquinone derivatives are inactive against the serine protease, porcine pancreatic elastase. 相似文献
97.
Gene flow from transgenic to nontransgenic soybean plants in the Cerrado region of Brazil 总被引:1,自引:0,他引:1
Abud S de Souza PI Vianna GR Leonardecz E Moreira CT Faleiro FG Júnior JN Monteiro PM Rech EL Aragão FJ 《Genetics and molecular research : GMR》2007,6(2):445-452
Evaluation of transgenic crops under field conditions is a fundamental step for the production of genetically engineered varieties. In order to determine if there is pollen dispersal from transgenic to nontransgenic soybean plants, a field release experiment was conducted in the Cerrado region of Brazil. Nontransgenic plants were cultivated in plots surrounding Roundup Ready transgenic plants carrying the cp4 epsps gene, which confers herbicide tolerance against glyphosate herbicide, and pollen dispersal was evaluated by checking for the dominant gene. The percentage of cross-pollination was calculated as a fraction of herbicide-tolerant and -nontolerant plants. The greatest amount of transgenic pollen dispersion was observed in the first row, located at one meter from the central (transgenic) plot, with a 0.52% average frequency. The frequency of pollen dispersion decreased to 0.12% in row 2, reaching 0% when the plants were up to 10 m distance from the central plot. Under these conditions pollen flow was higher for a short distance. This fact suggests that the management necessary to avoid cross-pollination from transgenic to nontransgenic plants in the seed production fields should be similar to the procedures currently utilized to produce commercial seeds. 相似文献
98.
Moreira Sofia Magalhães de Oliveira Mendes Tiago Antônio Mantovani Hilário Cuquetto 《Probiotics and antimicrobial proteins》2021,13(3):899-913
Probiotics and Antimicrobial Proteins - Bovicin HC5 is a peptide that has inhibitory activity against various pathogenic microorganisms and food spoilage bacteria. Aiming to improve the... 相似文献
99.
Thirty-four strains belonging to various species of the genus Thermus (T. aquaticus, "T. thermophilus,"
"T. brockianus,"
T. scotoductus, and genomic species 2) isolated from hot springs of different geographical areas were examined for plasmid content and restriction
fragment length polymorphism (RFLP) of plasmid DNAs. The four strains of the numerical taxonomy cluster E of genomic species
2 did not harbor plasmid DNA. Overall examination of the HindIII-RFLP profiling of plasmid DNA showed considerable variability between and within genomic species, with the exception
of presumed clonal isolates. In spite of this heterogeneity, HindIII plasmid digests within a numerical taxonomic cluster gave a subset of restriction fragments of similar or identical length.
Strains belonging to genomic species 2 or unclassified isolates from S. Pedro do Sul that harbored plasmid DNA (7 of the 14
strains studied) exhibited strong DNA homology between plasmid regions. No homologous sequences to these plasmid regions were
found in chromosomal DNA from strains isolated from S. Pedro do Sul in which no plasmids were detected. The strains belonging
to T. scotoductus formed two plasmid DNA homology groups, as estimated by probing with a plasmid fragment that coincided with the two numerical
taxonomy clusters proposed previously. Among the other species, homology of plasmid regions was also found between some strains.
Strong homology was also found between plasmid regions from some strains of different taxonomic groups, isolated from the
same and from different sources, suggesting that these sequences are highly conserved in plasmids present in Thermus. For plasmid-containing strains, results of plasmid RFLP profiling/DNA homology appear promising for the typing of Thermus at the level of biotypes or of individual strains, namely, for monitoring the diversity and frequency of isolates from a
particular hot spring.
Received: 24 October 1994 / Accepted: 6 March 1995 相似文献
100.
A new system to produce lignin peroxidase (LiP) continuously by Phanerochaete chrysosporium is described. A fixed-bed bioreactor with a pulsing device was used as the optimal bioreactor configuration. Addition of veratryl alcohol (1 mM), tryptophan (1 mM), no Mn2+ addition, low glucose addition rate (60–70 mg l–1 h) and an atmosphere of O2 gave maximum LiP activities of 700 U l–1, which are higher than those previously reported. 相似文献