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61.
Tenai Eguen Jorge Gomez Ariza Vittoria Brambilla Bin Sun Kaushal Kumar Bhati Fabio Fornara Stephan Wenkel 《植物学报(英文版)》2020,62(6):730-736
Photoperiod‐dependent flowering in rice is regulated by HEADING DATE 1 (Hd1), which acts as both an activator and repressor of flowering in a daylength‐dependent manner. To investigate the use of microProteins as a tool to modify rice sensitivity to the photoperiod, we designed a synthetic Hd1 microProtein (Hd1miP) capable of interacting with Hd1 protein, and overexpressed it in rice. Transgenic OX‐Hd1miP plants flowered significantly earlier than wild type plants when grown in non‐inductive long day conditions. Our results show the potential of microProteins to serve as powerful tools for modulating crop traits and unraveling protein function. 相似文献
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Flavia Varano Daniela Catarzi Matteo Falsini Fabrizio Vincenzi Silvia Pasquini Katia Varani Vittoria Colotta 《Bioorganic & medicinal chemistry》2018,26(12):3688-3695
In this study a new set of thiazolo[5,4-d]pyrimidine derivatives was synthesized. These derivatives bear different substituents at positions 2 and 5 of the thiazolopyrimidine core while maintaining a free amino group at position-7. The new compounds were tested for their affinity and potency at human (h) A1, A2A, A2B and A3 adenosine receptors expressed in CHO cells. The results reveal that the higher affinity of these new set of thiazolopyrimidines is toward the hA1 and hA2A adenosine receptors subtypes and is tuned by the substitution pattern at both the 2 and 5 positions of the thiazolopyrimidine nucleus. Functional studies evidenced that the compounds behaved as dual A1/A2A antagonists/inverse agonists. Compound 3, bearing a 5-((2-methoxyphenyl) methylamino) group and a phenyl moiety at position 2, displayed the highest affinity (hA1 Ki?=?10.2?nM; hA2A Ki?=?4.72?nM) and behaved as a potent A1/A2A antagonist/inverse agonist (hA1 IC50?=?13.4?nM; hA2A IC50?=?5.34?nM). 相似文献
64.
Irene Zubiri Vittoria Lombardi Michael Bremang Vikram Mitra Giovanni Nardo Rocco Adiutori Ching-Hua Lu Emanuela Leoni Ping Yip Ozlem Yildiz Malcolm Ward Linda Greensmith Caterina Bendotti Ian Pike Andrea Malaspina 《Molecular neurodegeneration》2018,13(1):60
Background
It is unclear to what extent pre-clinical studies in genetically homogeneous animal models of amyotrophic lateral sclerosis (ALS), an invariably fatal neurodegenerative disorder, can be informative of human pathology. The disease modifying effects in animal models of most therapeutic compounds have not been reproduced in patients. To advance therapeutics in ALS, we need easily accessible disease biomarkers which can discriminate across the phenotypic variants observed in ALS patients and can bridge animal and human pathology. Peripheral blood mononuclear cells alterations reflect the rate of progression of the disease representing an ideal biological substrate for biomarkers discovery.Methods
We have applied TMTcalibrator?, a novel tissue-enhanced bio fluid mass spectrometry technique, to study the plasma proteome in ALS, using peripheral blood mononuclear cells as tissue calibrator. We have tested slow and fast progressing SOD1G93A mouse models of ALS at a pre-symptomatic and symptomatic stage in parallel with fast and slow progressing ALS patients at an early and late stage of the disease. Immunoassays were used to retest the expression of relevant protein candidates.Results
The biological features differentiating fast from slow progressing mouse model plasma proteomes were different from those identified in human pathology, with only processes encompassing membrane trafficking with translocation of GLUT4, innate immunity, acute phase response and cytoskeleton organization showing enrichment in both species. Biological processes associated with senescence, RNA processing, cell stress and metabolism, major histocompatibility complex-II linked immune-reactivity and apoptosis (early stage) were enriched specifically in fast progressing ALS patients. Immunodetection confirmed regulation of the immunosenescence markers Galectin-3, Integrin beta 3 and Transforming growth factor beta-1 in plasma from pre-symptomatic and symptomatic transgenic animals while Apolipoprotein E differential plasma expression provided a good separation between fast and slow progressing ALS patients.Conclusions
These findings implicate immunosenescence and metabolism as novel targets for biomarkers and therapeutic discovery and suggest immunomodulation as an early intervention. The variance observed in the plasma proteomes may depend on different biological patterns of disease progression in human and animal model.65.
Andrea Bolognesi Letizia Polito Fabiola Olivieri Paola Valbonesi Luigi Barbieri M. Giulia Battelli M. Vittoria Carusi Eugenio Benvenuto Francesca Del Vecchio Blanco Antimo Di Maro Augusto Parente Mario Di Loreto Fiorenzo Stirpe 《Planta》1997,203(4):422-429
New single-chain (type 1) ribosome-inactivating proteins (RIPs) were isolated from the seeds of Basella rubra L. (two proteins) and from the leaves of Bougainvillea spectabilis Willd. (one protein). These RIPs inhibit protein synthesis both in a cell-free system, with an IC50 (concentration causing 50% inhibition) in the 10−10 M range, and by various cell lines, with IC50s in the 10−8–10−6 M range. All three RIPs released adenine not only from rat liver ribosomes but also from Escherichia coli rRNA, polyadenylic acid, herring sperm DNA, and artichoke mottled crinkle virus (AMCV) genomic RNA, thus being polynucleotide:adenosine
glycosidases. The proteins from Basella rubra had toxicity to mice similar to that of most type 1 RIPs (Barbieri et al., 1993, Biochim Biophys Acta 1154: 237–282) with
an LD50 (concentration that is 50% lethal) ≤ 8 mg · kg−1 body weight, whilst the RIP from Bougainvillea spectabilis had an LD50 >32 mg · kg−1. The N-terminal sequence of the two RIPs from Basella rubra had 80–93% identity, whereas it differed from the sequence of the RIP from Bougainvillea spectabilis. When tested with antibodies against various RIPs, the RIPs from Basella gave some cross-reactivity with sera against dianthin 32, and weak cross-reactivity with momordin I and momorcochin-S, whilst
the RIP from Bougainvillea did not cross-react with any antiserum tested. An RIP from Basella rubra and one from Bougainvillea spectabilis were tested for antiviral activity, and both inhibited infection of Nicotiana benthamiana by AMCV.
Received: 5 March 1997 / Accepted: 27 May 1997 相似文献
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67.
Maria Vittoria von Bülow Nidia Cavalcanti Franca Otto Richard Gottlieb Aura Maria Puentes Suarez 《Phytochemistry》1973,12(7):1805-1808
The wood of Aniba guianensis Aubl. (Lauraceae) contains benzyl benzoate, benzyl salicylate, sitosterol, O-methyleugenol, O-methylisoeugenol and the neolignan guianin for which the structure of 1-allyl-8-hydroxy-3-methoxy-7-methyl-4-oxo-6-piperonylbicyclo[3,2,1]oct-2-ene (VI) is proposed. 相似文献
68.
69.
M S Faussone-Pellegrini A Infantino P Matini A Masin B Mayer M Lise 《Histology and histopathology》1999,14(4):1119-1134
Patients suffering from idiopathic slow-transit chronic constipation have a delayed colonic transit referable to a decrease or loss of propagating contractions. Myogenic and/or neural mechanisms have been implicated in the pathophysiology of this dysfunction and neuronal abnormalities have been described at the ascending, descending and sigmoid colon. The morphology and motile behaviour of the ileocecocolonic region, which in healthy subjects regulates cecum filling and emptying, have never been investigated in such disease. Therefore, we endoscopically ascertained whether a motility impairment was present at these junctional areas and neither spontaneous nor provoked occlusive contractions were found at the cecocolonic junction. Light and electron microscope examination of the entire colon revealed apparently normal features of neurons, smooth muscle cells and interstitial cells of Cajal, while immunohistochemistry and quantitative analysis demonstrated neuronal anomalies at the junctional areas. These anomalies consisted of low total neuron density and significantly few VIP-immunoreactive neurons at the two enteric plexuses, significantly few NOS-immunoreactive neurons at the myenteric plexus and significantly more NOS-immunoreactive neurons at the submucous plexus. These findings exclude a myopathy and demonstrate the existence of a neuropathy. In particular, the presence at the ileocecocolonic region of few VIP- and NO-producing neurons suggests that there might be a reduced VIP and NO production which may result in a compromised relaxation and/or onset of propagating contractions, slowing down bolus transit. The presence at the proximal colon of such an abnormality might explain why left colectomy and/or cecorectal anastomosis are unsuccessful in patients with this disease. 相似文献
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