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排序方式: 共有210条查询结果,搜索用时 15 毫秒
41.
Vigliano FA Losada AP Castello M Bermúdez R Quiroga MI 《Cell and tissue research》2011,346(3):407-416
We performed structural and immunohistochemical studies on the thymus of juvenile turbot (Psetta maxima L.) in order to define its cellular composition. The thymic stroma was mainly composed of two subpopulations of reticulo-epithelial
cells (RECs). RECs immunoreactive to anti-actin antibody were distributed through the organ, while RECs that were cytokeratin-immunopositive
were located in the outer zone of the thymus. The parenchyma of the thymus was composed of several cell types such as lymphocytes/thymocytes,
lymphoblasts, melano-macrophages and to a lesser extent of nurse-like cells, immunoglobulin positive (Ig+) cells, mucous cells,
rodlet cells and neuroendocrine cells. CD3ε+ lymphocytes were mainly located in the outer zone. On the other hand, Ig+ cells
were observed in the transitional region between the inner and outer zones of the thymus. The neuroendocrine cells were large
and exhibited immunoreactivity to neuropeptide Y and vasoactive intestinal polypeptide. They were located in the inner zone
of the thymus in close association with lymphoblasts and lymphocytes/thymocytes. This work provides useful information on
the structure and cellular composition of the thymus of turbot, identifying several immunomarkers that allow the identification
of different cell types, providing the basis for further studies on the immune response of turbot against diseases. 相似文献
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43.
Stefano Guariniello Giovanni Colonna Raffaele Raucci Maria Costantini Gianni Di Bernardo Francesca Bergantino Giuseppe Castello Susan Costantini 《Biochimica et Biophysica Acta - Proteins and Proteomics》2014,1844(2):447-456
In humans we know 25 selenoproteins that play important roles in redox regulation, detoxification, immune-system protection and viral suppression. In particular, selenoprotein M (SelM) may function as thiol disulfide oxidoreductase that participates in the formation of disulfide bonds, and can be implicated in calcium responses. However, it presents a redox motif (CXXU), where U is a selenocysteine, and may also function as redox regulator because its decreased or increased expression regulated by dietary selenium alters redox homeostasis. No data are reported in literature about its involvement in cancer but only in neurodegenerative diseases. In this paper we evaluated the SelM expression in two hepatoma cell lines, HepG2 and Huh7, compared to normal hepatocytes. The results suggested its involvement in hepatocellular carcinoma (HCC) as well as its possible use to follow the progression of this cancer as putative marker. The aim of this study has been to analyze the structure–function relationships of SelM. Hence, firstly we studied the evolutionary history of this protein by phylogenetic analysis and GC content of genes from various species. So, we modeled the three-dimensional structure of the human SelM evaluating its energetic stability by molecular dynamics simulations. Moreover, we modeled some of its mutants to obtain structural information helpful for structure-based drug design. 相似文献
44.
Patrick MF Derkx Thomas Janzen Kim I Sørensen Jeffrey E Christensen Birgitte Stuer-Lauridsen Eric Johansen 《Microbial cell factories》2014,13(Z1):S5
The food industry is constantly striving to develop new products to fulfil the ever changing demands of consumers and the strict requirements of regulatory agencies. For foods based on microbial fermentation, this pushes the boundaries of microbial performance and requires the constant development of new starter cultures with novel properties. Since the use of ingredients in the food industry is tightly regulated and under close scrutiny by consumers, the use of recombinant DNA technology to improve microbial performance is currently not an option. As a result, the focus for improving strains for microbial fermentation is on classical strain improvement methods. Here we review the use of these techniques to improve the functionality of lactic acid bacteria starter cultures for application in industrial-scale food production. Methods will be described for improving the bacteriophage resistance of specific strains, improving their texture forming ability, increasing their tolerance to stress and modulating both the amount and identity of acids produced during fermentation. In addition, approaches to eliminating undesirable properties will be described. Techniques include random mutagenesis, directed evolution and dominant selection schemes. 相似文献
45.
Kristoffer Myczek Stephen T. Yeung Nicholas Castello David Baglietto-Vargas Frank M. LaFerla 《PloS one》2014,9(9)
Neuronal loss is a common component of a variety of neurodegenerative disorders (including Alzheimer''s, Parkinson''s, and Huntington''s disease) and brain traumas (stroke, epilepsy, and traumatic brain injury). One brain region that commonly exhibits neuronal loss in several neurodegenerative disorders is the hippocampus, an area of the brain critical for the formation and retrieval of memories. Long-lasting and sometimes unrecoverable deficits caused by neuronal loss present a unique challenge for clinicians and for researchers who attempt to model these traumas in animals. Can these deficits be recovered, and if so, is the brain capable of regeneration following neuronal loss? To address this significant question, we utilized the innovative CaM/Tet-DTA mouse model that selectively induces neuronal ablation. We found that we are able to inflict a consistent and significant lesion to the hippocampus, resulting in hippocampally-dependent behavioral deficits and a long-lasting upregulation in neurogenesis, suggesting that this process might be a critical part of hippocampal recovery. In addition, we provide novel evidence of angiogenic and vasculature changes following hippocampal neuronal loss in CaM/Tet-DTA mice. We posit that angiogenesis may be an important factor that promotes neurogenic upregulation following hippocampal neuronal loss, and both factors, angiogenesis and neurogenesis, can contribute to the adaptive response of the brain for behavioral recovery. 相似文献
46.
E. Guerriero M. Accardo F. Capone G. Colonna G. Castello S. Costantini 《European journal of histochemistry : EJH》2014,58(4)
Selenium is an essential trace mineral of fundamental importance to human healthy and exerts its biological function through selenoproteins. In particular, Selenoprotein M (SELM) is located in the endoplasmic reticulum and contains the common redox motif of cysteine-X-X-selenocysteine type. It attracts great attention due to its high expression in brain and its potential roles as antioxidant, neuroprotective, and cytosolic calcium regulator. Recently, our group found SELM over-expression in human hepatocellular carcinoma (HCC) cell lines. In this report some paraffin-embedded tissues from liver biopsy of patients with hepatitis C virus (HCV)-related cirrhosis and HCC were immunohistochemically stained and SELM expression scoring was evaluated. Our results evidence for the first time an increase of SELM expression in HCC liver tissues, and its gradual expression raise associated with an increased malignancy grade. Therefore, we propose to use i) SELM as putative marker for HCC as well as ii) simple immunohistochemistry technique to distinguish between the different grades of malignancy.Key words: Hepatocellular carcinoma, SELM, immunohistochemistry 相似文献
47.
Spatial subsidies are resources transferred from one ecosystem to another and which can greatly affect recipient systems. Increased subsidy quantity is known to increase these effects, but subsidy quality is likely also important. We examined the effects of leaf litter quality (varying in nutrient and tannin content) in pond mesocosms on gray treefrog (Hyla versicolor) biomass export, as well as water quality and ecosystem processes. We used litter from three different tree species native to Missouri [white oak (Quercus alba), northern red oak (Quercus rubra), and sugar maple (Acer saccharum)], one non-native tree [white pine (Pinus strobus)], and a common aquatic grass [prairie cordgrass (Spartina pectinata)]. We found that leaf litter species affected almost every variable we measured. Gray treefrog biomass export was greatest in mesocosms with grass litter and lowest with white oak litter. Differences in biomass export were affected by high tannin concentrations (or possibly the correlated variable, dissolved oxygen) via their effects on survival, and by primary production, which altered mean body mass. Effects of litter species could often be traced back to the characteristics of the litter itself: leaf nitrogen, phosphorus, and tannin content, which highlights the importance of plant functional traits in affecting aquatic ecosystems. This work and others stress that changes in forest species composition could greatly influence aquatic systems and aquatic–terrestrial linkages. 相似文献
48.
A Leprini G Garaventa S Bottero A E Leprini E Pallestrini E Castello E A Pallestrini 《Bollettino della Società italiana di biologia sperimentale》1990,66(11):1073-1080
In this study fibrous nasal polyps, obtained from four patients, were analyzed by means of immunocytochemical methods for the presence of interstitial hematic cell infiltrate and HLA-DR molecule expression. This histologic type accounted for 36.4% of nasal polyps studied. Our results demonstrated that cells belonging to monocyte-macrophage lineage were mainly detected within fibrous and edematous zones (greater than 50%), whereas T cells were found within the subepithelial peripheral connective tissue (greater than 60%). Surface and gland epithelial cells appeared to be more intensely stained for HLA-DR molecules than nasal epithelium of normal subjects, thus indicating that the intensity of HLA-DR molecule expression correlated with the presence of a hematic cell infiltrate. Nasal polyps are a frequent pathology whose etiology has not yet been completely clarified. The present study provides additional information about the fibrous polyp structure and can support some speculations on the nasal polyp etiology. 相似文献
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50.
Giuliana Castello Coatti Juliana Cristina Marcarini Daniele Sartori Queli Cristina Fidelis Dalva Trevisan Ferreira Mário Sérgio Mantovani 《Cytotechnology》2016,68(4):1161-1170
Aspidospermine is an indole alkaloid with biological properties associated with combating parasites included in the genera Plasmodium, Leishmania and Trypanossoma. The present study evaluated the cytotoxicity (resazurin test), genotoxicity (comet assay) and mechanism of action (gene expression analysis via qRT-PCR) of this alkaloid in human HepG2 cells. The results demonstrated that treatment with aspidospermine was both cytotoxic (starting at 75 μM) and genotoxic (starting at 50 μM). There was no significant modulation of the expression of the following genes: GSTP1 and GPX1 (xenobiotic metabolism); CAT (oxidative stress); TP53 and CCNA2 (cell cycle); HSPA5, ERN1, EIF2AK3 and TRAF2 (endoplasmic reticulum stress); CASP8, CASP9, CASP3, CASP7, BCL-2, BCL-XL BAX and BAX (apoptosis); and PCBP4, ERCC4, OGG1, RAD21 and MLH1 (DNA repair). At a concentration of 50 μM (non-cytotoxic, but genotoxic), there was a significant increase in the expression of CYP1A1 (xenobiotic metabolism) and APC (cell cycle), and at a concentration of 100 μM, a significant increase in the expression of CYP1A1 (xenobiotic metabolism), GADD153 (endoplasmic reticulum stress) and SOD (oxidative stress) was detected, with repression of the expression of GR (xenobiotic metabolism and oxidative stress). The results of treatment with aspidospermine at a 100 μM concentration (the dose indicated in the literature to achieve 89 % reduction of the growth of L. amazonensis) suggest that increased oxidative stress and an unfolded protein response (UPR) occurred in HepG2 cells. For the therapeutic use of aspidospermine (antiparasitic), chemical alteration of the molecule to achieve a lower cytotoxicity/genotoxicity in host cells is recommended. 相似文献