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151.
Summary The cell subpopulations in the haemolymph ofPlanorbarius corneus were distinguished by means of flow cytometry. An antibody againstn-acetylmuramic acid was prepared and used as a cellular marker to recognize the cell types forming the subpopulations. The spreading haemocytes showed a positive reaction for anti-n-acetylmuramic acid; round haemocytes gave a negative reaction. 相似文献
152.
Folate metabolism, also known as one-carbon metabolism, is required for several cellular processes including DNA synthesis, repair and methylation. Impairments of this pathway have been often linked to Alzheimer’s disease (AD). In addition, increasing evidence from large scale case-control studies, genome-wide association studies, and meta-analyses of the literature suggest that polymorphisms of genes involved in one-carbon metabolism influence the levels of folate, homocysteine and vitamin B12, and might be among AD risk factors. We analyzed a dataset of 30 genetic and biochemical variables (folate, homocysteine, vitamin B12, and 27 genotypes generated by nine common biallelic polymorphisms of genes involved in folate metabolism) obtained from 40 late-onset AD patients and 40 matched controls to assess the predictive capacity of Artificial Neural Networks (ANNs) in distinguish consistently these two different conditions and to identify the variables expressing the maximal amount of relevant information to the condition of being affected by dementia of Alzheimer’s type. Moreover, we constructed a semantic connectivity map to offer some insight regarding the complex biological connections among the studied variables and the two conditions (being AD or control). TWIST system, an evolutionary algorithm able to remove redundant and noisy information from complex data sets, selected 16 variables that allowed specialized ANNs to discriminate between AD and control subjects with over 90% accuracy. The semantic connectivity map provided important information on the complex biological connections among one-carbon metabolic variables highlighting those most closely linked to the AD condition. 相似文献
153.
Giorgio Bolis Antonio Pillan Sergio Mantegani Enzo Brambilla Alessandro Dolmella 《Journal of molecular modeling》1995,1(4):188-195
A 5-HT1A pharmacophore has been obtained employing a set of rigid templates encompassing the 5-HT1A structure. The use of rigid templates allowed us to overcome the discrepancy found when flexible structures where the energy of the active conformers are sometimes higher than the global minimum energy are used. On the basis of the results herein reported the three-dimensional requirements necessary for the binding interaction have been defined within this set of molecules. In this study forbidden zones of the receptor have been characterised. The pharmacophore model derived places some agonist/antagonist pharmacophore models appeared in the literature. 相似文献
154.
Evangelos Giampazolias Oliver Schulz Kok Haw Jonathan Lim Neil C. Rogers Probir Chakravarty Naren Srinivasan Oliver Gordon Ana Cardoso Michael D. Buck Enzo Z. Poirier Johnathan Canton Santiago Zelenay Stefano Sammicheli Natalia Moncaut Sunita Varsani-Brown Ian Rosewell Caetano Reis e Sousa 《Cell》2021,184(15):4016-4031.e22
155.
Variation in structure and plant regeneration of Agrobacterium rhizogenes transformed and control roots of the potato cv. Bintje 总被引:2,自引:0,他引:2
M. P. Ottaviani J. H. N. Schel Ch. H. Hänisch ten Cate 《Plant Cell, Tissue and Organ Culture》1990,20(1):25-34
Agrobacterium rhizogenes transformed and control roots of the tetraploid potato cv. Bintje were compared. Transformed roots were obtained after infection by A. rhizogenes 15834 or 1855. Both in leaf and stem segments, more roots were formed at the basal side of the segments, indicative for a polarity in root formation. As compared to control roots the transformed roots are characterized by smaller and more densely stained cells, a zone of cell division, and smaller statoliths. These characteristics are correlated with vigorous growth, high branching incidence and diminished geotropism. The plant regeneration procedure according to Ooms et al. [1] was modified. The transformed roots required less 2,4-D than control roots for the induction of shoot-competent calli. The callus and shoot induction phases were reduced from 8 and 6 weeks to 3 and 3 weeks, respectively. Upon induction, 25%, 58% and 61% of the root clones originating from tuber, stem and leaf, respectively, produced shoots, whereas all of the control roots produced shoots. Shoot outgrowth occurred on liquid MS medium in the absence of hormones.Abbreviations Ri-root
Agrobacterium rhizogenes transformed root
- BAP
benzylaminopurine
- IAA
indoleacetic acid
- GA3
gibberellic acid
- NAA
naphthaleneacetic acid
- 2,4-D
2,4 dichlorophenoxyacetic acid 相似文献
156.
Intestinal cell types in the freshwater snail planorbarius corneus: Histochemical, immunocytochemical and ultrastructural observations 总被引:1,自引:0,他引:1
The intestinal cell types of the pulmonate gastropodPlanorbarius corneus were studied using histochemical, immunocytochemical and ultrastructural procedures. Supporting cells, mucous cells and gland cells were observed in the intestine epithelium. The supporting cells seem to be involved in absorption process, showing endocytosis vesicles, evidence of lysosomal activity and storage of reserve materials. The presence of epithelial cells specialized in secretion indicates that digestive enzymes may be produced. Indeed, immunoreactive alpha-amylase molecules have been demonstrated. Some gland cells showed the ultrastructural features of invertebrate and vertebrate enteroendocrine cells and were also positive to vertebrate anti-insulin, anti-gastrin and anti-serotonin antibodies. 相似文献
157.
Decellularized colorectal cancer matrix as bioactive microenvironment for in vitro 3D cancer research 下载免费PDF全文
158.
Li Cui Wang Peng Lombi Enzo Wu Jingtao Blamey F. Pax C. Fernández Victoria Howard Daryl L. Menzies Neal W. Kopittke Peter M. 《Plant and Soil》2018,425(1-2):309-319
Plant and Soil - Arabidopsis thaliana is the model plant that is mainly used in studying cellulose and hemicellulose (CH) biosynthesis. Unfortunately, A. thaliana does not associate with mycorrhiza... 相似文献
159.
Lucio Tentori Carlo Leonetti Francesco Lozupone Enzo Bonmassar 《Cancer immunology, immunotherapy : CII》1996,41(6):375-383
The antitumor and antimetastatic activity of dacarbazine (DTIC) alone or in combination with cyclophosphamide (CY) was tested in C57BL/6 mice bearing Lewis lung carcinoma (3LL). Treatment with both agents significantly reduced tumor growth and the number of metastases. These effects were associated with marked changes of the biochemical and immunological properties of drug-treated 3LL cells, i.e. (a) reduction of 6 integrin expression, (b) increased susceptibility to natural immunity in vivo, as measured in terms of rapid clearance from mouse lungs of prelabeled 3LL cells injected i.v. and (c) increased immunogenicity, as assessed by T-cell-mediated immune responses (i.e. graft rejection by intact syngeneic mice, and frequency of specific CTL precursors recognizing DTIC/CY-treated cancer cells). The immunotherapeutic advantage afforded by increased immunosensitivity and immunogenicity of 3LL cells exposed to DTIC+CY appears to be markedly reduced in vivo by the profound immunodepressive effects of these drugs. Within this context, addition of interleukin-2 was found to increase the antitumor and antimetastatic activity of this chemotherapeutic regimen. The present study shows, for the first time in a solid tumor model, that a biological response modifier increases the antitumor efficacy of drugs that are able to affect the immunological properties of cancer cells. 相似文献
160.
Professor Enzo Raise Luca Guerra Dimitri Viza Giancarlo Pizza Caterina De Vinci Maria Luisa Schiattone Leonarda Rocaccio Maria Cicognani Francesco Gritti 《Biotherapy》1996,9(1-3):49-54
The efficiency of HIV-1 specific transfer factor (TF) administration, combined with Zidovudine (ZDV), in asymptomatic persistent generalised lymphadenopaty, or AIDS related complex (ARC) patients was evaluated. Twenty patients were randomly assigned to receive only ZDV (1st group) or ZDV together with HIV-1-specific TF (2nd group). HIV-1-specific TF was administered orally at 2 × 107 cell equivalent daily for 15 days, and thereafter once a week for up to 6 months. There were no significant differences between the two groups in clinical evolution, red blood cells, haemoglobin, lymphocytes, CD20 subset, transaminases,β-2-microglobulin, p24 antigen. White blood cells, CD8 lymphocytes as well as IL-2 levels increased in the second group, while the CD4 subset increased in the first group. The combination treatment with ZDV and TF appeared to be safe and well tolerated. Furthermore, levels of serum cytokines were investigated in 10 patients (8 asymptomatic and 2 ARC) treated with ZDV, and compared with 5 patients of the 2nd group (3 asymptomatic and 2 ARC) treated with ZDV plus HIV-1-specific TF. Peripheral lymphocytes, CD4, CD8 subsets, IL-2, TNFα, IL-6, p24 antigen, IL-2 soluble lymphocyte receptors (sR), CD4sR, CD8sR and ß-2-microglobulin were evaluated at the baseline and at the 3rd month. The CD4 subset was not significantly different in the two groups, whilst IL-2 increased in the 2nd group receiving ZDV plus TF, suggesting an activation of the Th1 secretion pattern. 相似文献