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531.
Chiara Scanarotti Anna Maria Bassi Mariafrancesca Catalano Chiara Guida Rosella Coradeghini Carla Falugi Mariagrazia Aluigi Pierluigi Santi Edoardo Raposio 《Chemico-biological interactions》2010,184(3):474-483
Stem cell models offer an opportunity both for therapeutic use and for the assessment of alternative in vitro models. Human lipoaspirate is a source of adult stem cells (pre-adipocytes), which are able to differentiate into various phenotypes, such as neurogenic lineage. Here, we analyse the suitability of these in vitro models in screening exogenous compounds, such as environmental pollutants, that may affect adipose cells and neurogenic development. To evaluate neurogenic differentiation, we analysed expression of cholinergic system and acetylcholinesterase immunoreactivity. Heterocyclic derivatives of polycyclic aromatic hydrocarbons (PAHs) are often significant components of environmental contaminants. As they contain inducers of cytochrome P450 1A1 (CYP1A1), we explored the activity of CYP1A1-related enzymes, i.e. 7-ethoxycoumarin- and 7-ethoxyresorufin-O-deethylase (ECOD and EROD) in both cell systems in basal conditions and after exposure to non-cytotoxic doses of β-naphthoflavone (BNF), a well-known PAH-type inducer. Both cell models showed basal and inducible levels of ECOD. Analysis of CYP1A1 protein expression and EROD-related enzyme activity confirmed the inducibility of the CYP1A1 isoform by BNF. These results demonstrate that mesenchymal adult stem cells can constitute innovative models. We therefore propose the use of pre-adipocytes and their neurogenic derivates to evaluate the cytotoxic/biological effects of unintended exposure to contaminants. 相似文献
532.
Marcus H. Borges Janet Pullockaran Patrick M. Catalano Marc U. Baumann Stacy Zamudio Nicholas P. Illsley 《生物化学与生物物理学报:疾病的分子基础》2019,1865(9):2411-2419
We have previously described regulation of syncytial GLUT1 glucose transporters by IGF-I. Despite this, it is not clear what signal regulates transplacental glucose transport. In this report we asked whether changes in GLUT1 expression and glucose transport activity in diabetic pregnancies were associated with alterations in the fetal IGF axis. Cord blood samples and paired syncytial microvillous and basal membranes were isolated from normal term pregnancies and pregnancies characterized by gestational diabetes type A2 (GDM A2) and pre-existing insulin-dependent diabetes mellitus (IDDM). Circulating IGF-I, basal membrane GLUT1 expression and glucose transporter activity were correlated with birth weight, but only in control, not diabetic groups. Basal membrane GLUT1 and transporter activity were correlated with IGF-I concentrations in control, but not diabetic groups. IGF binding protein (IGFBP) binding capacity showed a ≥50% reduction in the diabetic groups compared to control; both showed a higher level of free IGF-I. The absence of a correlation between birth weight and factors such as fetal IGF-I or GLUT1 expression in the diabetic groups suggests that IGF-I-stimulated effects may have reached a limiting threshold, such that further increases in IGF-I (or GLUT1) are without effect. These data support that fetal IGF-I acts as a fetal nutritional signal, modulating placental GLUT1 expression and birth weight via altered levels of fetal circulating IGFBPs. Diabetes appears to exert its effects on fetal and placental factors prior to the third trimester and, despite good glycemic control immediately prior to, and in the third trimester, these effects persist to term. 相似文献
533.
534.
Elisabetta Schiliro Stefano Predieri Assunta Bertaccini 《Plant Molecular Biology Reporter》2001,19(3):271-272
Pyrus communis L. is the most important pear species for European production. Very few cultivars satisfy standards for fruit quality and
clonal fidelity; thus, accurate verification of cultivar identity for checking propagation material and patent protection
is important. We evaluated the randomly amplified polymorphic DNA (RAPD) technique for its ability to identify genetic differences
among standard pear (Pyrus communis L.) cultivars, William, Passa Crassana, and Conference, and three gamma-ray induced variants. To identify genotype-specific
markers, we used thirty 10-mer and two 11-mer sequences, annealing temperatures from 36–45°C, 2Taq polymerases (AmpliTaq and Stoffel fragment, both from former Perkin Elmer Cetus), and 2–4 replicate amplifications. Of the
32 primers (30 from Operon Technologies, Alameda, CA, USA), very few distinguished William from Passa Crassana, and only 1
could clearly differentiate all 3 cultivars. Two primers that did not reveal polymorphisms when used singly, generated polymorphic
patterns that distinguished standard from gamma-ray-treated material when used in combination. We show that RAPD analyses
can discriminate pear genotypes and suggest this technique as a reliable and inexpensive method for marker-facilitated screening
of propagation material and for patent protection. 相似文献