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51.
52.
Tatiana A. Vega Graciela M. Nestares Roxana Zorzoli Liliana Picardi 《Acta Physiologiae Plantarum》2006,28(5):427-431
Regeneration efficiency from three different regions of cotyledonary explants was examined in six sunflower inbred lines.
Proximal, middle and distal regions from seedling cotyledons were cultured on regeneration medium supplemented with growth
regulators. Plant regeneration by direct organogenesis was observed after four weeks. Significant differences among inbred
lines were found for regeneration percentage and average number of shoots per total explants. Also a decreasing regeneration
capacity was observed from proximal to distal sections for all inbred lines. Regeneration ability from cotyledonary explants
in this species is strongly influenced by the genotype and by the region from which the explant was obtained. The distance
to the cotyledonary node plays a preponderant role in the expression of shoot forming capacity. Shoot differentiation via seedling cotyledons depends upon the presence of the proximal region of cotyledon regardless of the genotype. 相似文献
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54.
Non-coding RNAs as theranostics in human cancers 总被引:1,自引:0,他引:1
Theranostics was coined originally as a term used to describe a system that combines diagnosis and therapy, aiming to provide the tools for personalized medicine. This review reasserts the grounds for regarding non-coding RNAs (ncRNA) as theranostics in human cancers. The microRNAs (miRNAs) are the most well studied ncRNAs in recent years; their pivotal role in orchestrating tumor initiation and progression has been confirmed in all types of cancers. Hence, these small ncRNAs have emerged as attractive therapeutic targets and diagnostic tool. Various approaches to use their therapeutic potential have been taken, here we summarize the most important ones. In the near future, the focus of theranostics will be shifted towards longer and mechanistically more versatile ncRNAs, and we included some recent advances supporting this view. 相似文献
55.
New tricks of an old pattern: structural versatility of scorpion toxins with common cysteine spacing
Saucedo AL Flores-Solis D Rodríguez de la Vega RC Ramírez-Cordero B Hernández-López R Cano-Sánchez P Noriega Navarro R García-Valdés J Coronas-Valderrama F de Roodt A Brieba LG Domingos Possani L del Río-Portilla F 《The Journal of biological chemistry》2012,287(15):12321-12330
Scorpion venoms are a rich source of K(+) channel-blocking peptides. For the most part, they are structurally related small disulfide-rich proteins containing a conserved pattern of six cysteines that is assumed to dictate their common three-dimensional folding. In the conventional pattern, two disulfide bridges connect an α-helical segment to the C-terminal strand of a double- or triple-stranded β-sheet, conforming a cystine-stabilized α/β scaffold (CSα/β). Here we show that two K(+) channel-blocking peptides from Tityus scorpions conserve the cysteine spacing of common scorpion venom peptides but display an unconventional disulfide pattern, accompanied by a complete rearrangement of the secondary structure topology into a CS helix-loop-helix fold. Sequence and structural comparisons of the peptides adopting this novel fold suggest that it would be a new elaboration of the widespread CSα/β scaffold, thus revealing an unexpected structural versatility of these small disulfide-rich proteins. Acknowledgment of such versatility is important to understand how venom structural complexity emerged on a limited number of molecular scaffolds. 相似文献
56.
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In the present study, we evaluated whether reproductive condition affects female reproductive behaviour in the induced ovulator
Ctenomys talarum. We also explored the effect of the interaction with a male on the reproductive condition of females. To evaluate this, we
arranged mating trials and evaluated female reproductive behaviour. Reproductive status of females was evaluated using a combined
approach of vaginal smears, urinary progesterone and oestradiol, and ovarian histology. Behaviours denoting attraction (‘male
sniff’ and ‘mount attempts’) and mutual courtship behaviours (‘spin’ and copula) were correlated with vaginal cytology before
and oestradiol and progesterone levels in urine 12 h after male–female encounter. After 24 h of the interaction, oestradiol
levels and vaginal epithelization increased while progesterone levels decreased in soliciting females. C. talarum females’ reproductive behaviour was related to its physiological reproductive state and vaginal cytology. The kind of male
interaction, whether couples copulated or remained indifferent affected the later status of females. Females are induced ovulators
by mating but male presence and interaction also affected other components of their reproductive physiology such as ovarian
hormones and vaginal cytology. 相似文献
58.
Viñas-Bravo O Martinez-Pascual R Vega-Baez JL Gómez-Calvario V Sandoval-Ramírez J Montiel-Smith S Meza-Reyes S López-De Rosas A Martínez-Montiel M Reyes M Ruiz JA 《Steroids》2012,77(1-2):59-66
We report a facile protocol to obtain 22-substituted furostans and pseudosapogenins in high yields from (25R)- and (25S)-sapogenins. This method involves the treatment of the sapogenin with acetic-trifluoroacetic mixed anhydride and BF(3)·OEt(2) at room temperature, followed by the addition of a nucleophile (H(2)O, MeOH or KSeCN). In the case of 22-hydroxyfurostans, they can be transformed to pseudosapogenins by treatment with p-toluensulfonic acid. 相似文献
59.
Karina Roxana Gheorghe Syed Sadique Patrick Leclerc Helena Idborg Ivonne Wobst Anca Irinel Catrina Per-Johan Jakobsson Marina Korotkova 《Arthritis research & therapy》2012,14(3):R121
Introduction
Rheumatoid arthritis (RA) is a chronic inflammatory disease in which prostaglandin E2 (PGE2) displays an important pathogenic role. The enzymes involved in its synthesis are highly expressed in the inflamed synovium, while little is known about 15- prostaglandin dehydrogenase (15-PGDH) that metabolizes PGE2. Here we aimed to evaluate the localization of 15-PGDH in the synovial tissue of healthy individuals or patients with inflammatory arthritis and determine the influence of common RA therapy on its expression.Methods
Synovial tissue specimens from healthy individuals, psoriatic arthritis, ostheoarthritis and RA patients were immunohistochemically stained to describe the expression pattern of 15-PGDH. In addition, the degree of enzyme staining was evaluated by computer analysis on stained synovial biopsies from two groups of RA patients, before and after RA specific treatment with either intra-articular glucocorticoids or oral methotrexate therapy. Prostaglandins derived from the cyclooxygenase (COX) pathway were determined by liquid-chromatography mass spectrometry in supernatants from interleukin (IL) 1β-activated fibroblast-like synoviocytes (FLS) treated with methotrexate.Results
15-PGDH was present in healthy and inflamed synovial tissue, mainly in lining macrophages, fibroblasts and vessels. Intra-articular glucocorticoids showed a trend towards reduced 15-PGDH expression in RA synovium (p = 0.08) while methotrexate treatment left the PGE2 pathway unaltered both in biopsies ex vivo and in cultured FLS.Conclusions
Early methotrexate therapy has little influence on the expression of 15-PGDH and on any of the PGE2 synthesizing enzymes or COX-derived metabolites. Thus therapeutic strategies involving blocking induced PGE2 synthesis may find a rationale in additionally reducing local inflammatory mediators. 相似文献60.
Cyntia Anabel Amorosi Helena Myskóva Mariela Roxana Monti Carlos Enrique Argara?a Masashi Morita Stephan Kemp Raquel Dodelson de Kremer Lenka Dvoráková Ana María Oller de Ramírez 《PloS one》2012,7(12)
X-linked adrenoleukodystrophy (X-ALD) is an inherited metabolic disease associated with mutations in the ABCD1 gene that encodes an ATP-binding cassette transporter protein, ALDP. The disease is characterized by increased concentrations of very long-chain fatty acids (VLCFAs) in plasma and in adrenal, testicular and nervous tissues, due to a defect in peroxisomal VLCFA β-oxidation. In the present study, we analyzed 10 male patients and 17 female carriers from 10 unrelated pedigrees with X-ALD from Argentina. By sequencing the ABCD1 we detected 9 different mutations, 8 of which were novel. These new mutations were verified by a combination of methods that included both functional (western blot and peroxisomal VLCFA β-oxidation) and bioinformatics analysis. The spectrum of novel mutations consists of 3 frameshift (p.Ser284fs*16, p.Glu380Argfs*21 and p.Thr254Argfs*82); a deletion (p.Ser572_Asp575del); a splicing mutation (c.1081+5G>C) and 3 missense mutations (p.Ala341Asp, p.His420Pro and p.Tyr547Cys). In one patient 2 changes were found: a known missense (p.His669Arg) and an unpublished amino acid substitution (p.Ala19Ser). In vitro studies suggest that p.Ala19Ser is a polymorphism. Moreover, we identified two novel intronic polymorphisms and two amino acid polymorphisms. In conclusion, this study extends the spectrum of mutation in X-ALD and facilitates the identification of heterozygous females. 相似文献