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排序方式: 共有617条查询结果,搜索用时 31 毫秒
1.
Agricultural biotechnologies embrace a large array of conventional and modern technologies, spanning from composting organic by-products of agriculture to innovative improvement of quality traits of about twenty out of the mostly cultivated plants. In EU a rather restrictive legislative framework has been installed for GMOs, requiring a risk assessment disproportionate with respect to conventional agriculture and organic farming products. The latter are far from being proved safe for human and animal health, and for the environment.Biotechnology of GMOs has been overtaken by biopolitics. On one side there are biotechnological challenges to be tackled, on another side there is plenty of ground for biopolitical decisions about GMOs. Perhaps the era of harsh confrontation could be fruitfully replaced by sensible cooperation, in order to get a sustainable agricultural development. 相似文献
2.
Vincenzo Carelli Antonio Casini Alessandro Finazzi-Agro Felice Liberatore Silvano Tortorella 《Free radical research》1988,4(6):397-402
The nicotinamide adenine dinucleotide dimers (NAD)2 obtained by electrochemical reduction of NAD+ are oxidized by adriamycin in anaerobic photocatalyzed reaction yielding NAD+ and 7-deoxyadriamyci-none. Under the same conditions NADH is not oxidized. 相似文献
3.
Rapid prenatal diagnosis of chromosomal aneuploidies by fluorescence in situ hybridization: clinical experience with 4,500 specimens. 总被引:13,自引:2,他引:11
B E Ward S L Gersen M P Carelli N M McGuire W R Dackowski M Weinstein C Sandlin R Warren K W Klinger 《American journal of human genetics》1993,52(5):854-865
Detection of chromosome aneuploidies in uncultured amniocytes is possible using fluorescence in situ hybridization (FISH). We herein describe the results of the first clinical program which utilized FISH for the rapid detection of chromosome aneuploidies in uncultured amniocytes. FISH was performed on physician request, as an adjunct to cytogenetics in 4,500 patients. Region-specific DNA probes to chromosomes 13, 18, 21, X, and Y were used to determine ploidy by analysis of signal number in hybridized nuclei. A sample was considered to be euploid when all autosomal probes generated two hybridization signals and when a normal sex chromosome pattern was observed in greater than or equal to 80% of hybridized nuclei. A sample was considered to be aneuploid when greater than or equal to 70% of hybridized nuclei displayed the same abnormal hybridization pattern for a specific probe. Of the attempted analyses, 90.2% met these criteria and were reported as informative to referring physicians within 2 d of receipt. Based on these reporting parameters, the overall detection rate for aneuploidies was 73.3% (107/146), with an accuracy of informative results for aneuploidies of 93.9% (107/114). Compared to cytogenetics, the accuracy of all informative FISH results, euploid and aneuploid, was 99.8%, and the specificity was 99.9%. In those pregnancies where fetal abnormalities had been observed by ultrasound, referring physicians requested FISH plus cytogenetics at a significantly higher rate than they requested cytogenetics alone. The current prenatal FISH protocol is not designed to detect all chromosome abnormalities and should only be utilized as an adjunctive test to cytogenetics. This experience demonstrates that FISH can provide a rapid and accurate clinical method for prenatal identification of chromosome aneuploidies. 相似文献
4.
Luigi Bosco Cristiana Valle Daniela Willems 《Development, growth & differentiation》1993,35(3):257-270
After lentectomy of larval Xenopus laevis , the outer cornea undergoes tissue transformation resulting in formation of a new lens. This lens regeneration is triggered and sustained by neural retina. In the present study, lens-forming transformation of the outer cornea was completed in vitro when the outer cornea was cultured within the lentectomized eye-cup. Well-differentiated lens fiber cells, which showed positive immunofluorescence for total crystallins, were also formed when the outer cornea was cultivated with the retina. No lens tissue was formed when the cornea was cultured alone. Lens-forming transformation, originating from the cornea three and five days after lentectomy, completely regressed when the tissue was isolated in vitro . Fom the present and previous findings, we concluded that, the interaction of corneal cells with the retina plays a decisive role in lens regeneration in situ . 相似文献
5.
Stefania Motta Marcello Monti Silvia Sesana Ruggero Caputo Stephana Carelli Riccardo Ghidoni 《生物化学与生物物理学报:疾病的分子基础》1993,1182(2):147-151
This paper investigates the ceramide composition of the psoriatic scale compared with that of normal human SC. A method was optimalized, based on TLC separation followed by densitometry, allowing the provision of good resolution and quantification of ceramide fractions from both normal and pathological specimens. Seven ceramide fractions were isolated and submitted to compositional analysis. The obtained results suggested a revisitation of previous ceramide designation. Therefore a simple classification is suggested, based on grouping ceramides carrying structural similarities under common codes. According to these rules, ceramides were grouped into five classes designated as: (1) Cer[EOS], which contains ester-linked fatty acids, ω-OH fatty acids and sphingosines; (2) Cer[NS], which contains non-OH fatty acids and sphingosines; (3) Cer[NP], which contains non-OH fatty acids and phytosphingosines; (4) Cer[AS], which contains α-OH fatty acids and sphingosines; (5) Cer[AP], which contains α-OH fatty acids and phytosphingosines. Analysis of ceramides from the psoriatic scale, compared to those from normal human SC, resulted in an impairment of the Cer[EOS] content as well as of the ceramides containing phytosphingosine, with concurrent increase in ceramides containing sphingosine, being the total amount maintained identical. Since one of the suggested pathways for phytosphingosine biosynthesis involves the water addition to the corresponding sphingosine double bond, we can speculate that the observed alterarion is due to a deranged water bioavailability, associated with psoriaris. 相似文献
6.
Cristiana Sbrana Manuela Giovannetti Marcello Buiatti Emanuela Storti 《Journal of Phytopathology》1993,139(1):1-9
Tissue cultures of Nicotiana tabacum were utilized to investigate the mechanisms associated with host specificity and non-host incompatibility in mycorrhizal and pathogenic fungi. They were tested for expression of resistance to different species of mycorrhizal fungi and to a fungal pathogen of tobacco, Thielaviopsis basicola , by monitoring the production of callose, phenolic compounds and peroxidases in dual cultures. Tobacco cells reacted to the presence of all the mycorrhizal fungi with callose deposits, whereas callose was nearly always absent in tobacco cells inoculated with their pathogen T. basicola. The broad-host range ectomycorrhizal fungi Hebeloma crustuliniforme, Lac-caria laccata and Suilhis granulatus elicited less intense responses than did Hymenoscyphus ericae. The results obtained for phenolic production and peroxidase activity were consistently similar to those obtained for callose deposition. They showed that H. ericae , an endomycorrhizal symbiont of Ericaceae, was highly incompatible with tobacco cells and that the tobacco pathogen T. basicola did not elicit strong reactions in the cells of its host. In this paper, the possibility of utilizing callus cultures as a simple model system to study both the different degrees of compatibility and the early events of recognition between mycorrhizal fungi and their host or non-host plants is discussed. 相似文献
7.
Cristiana Iosef Claudio M. Martin Marat Slessarev Carolina Gillio-Meina Gediminas Cepinskas Victor K. M. Han Douglas D. Fraser 《Journal of cellular and molecular medicine》2023,27(1):141-157
Coronavirus disease 2019 (COVID-19) is a systemic inflammatory condition with high mortality that may benefit from personalized medicine and high-precision approaches. COVID-19 patient plasma was analysed with targeted proteomics of 1161 proteins. Patients were monitored from Days 1 to 10 of their intensive care unit (ICU) stay. Age- and gender-matched COVID-19-negative sepsis ICU patients and healthy subjects were examined as controls. Proteomic data were resolved using both cell-specific annotation and deep-analysis for functional enrichment. COVID-19 caused extensive remodelling of the plasma microenvironment associated with a relative immunosuppressive milieu between ICU Days 3–7, and characterized by extensive organ damage. COVID-19 resulted in (1) reduced antigen presentation and B/T-cell function, (2) increased repurposed neutrophils and M1-type macrophages, (3) relatively immature or disrupted endothelia and fibroblasts with a defined secretome, and (4) reactive myeloid lines. Extracellular matrix changes identified in COVID-19 plasma could represent impaired immune cell homing and programmed cell death. The major functional modules disrupted in COVID-19 were exaggerated in patients with fatal outcome. Taken together, these findings provide systems-level insight into the mechanisms of COVID-19 inflammation and identify potential prognostic biomarkers. Therapeutic strategies could be tailored to the immune response of severely ill patients. 相似文献
8.
Genetic Diversity of Isolates of Glomus mosseae from Different Geographic Areas Detected by Vegetative Compatibility Testing and Biochemical and Molecular Analysis 下载免费PDF全文
Manuela Giovannetti Cristiana Sbrana Patrizia Strani Monica Agnolucci Valeria Rinaudo Luciano Avio 《Applied microbiology》2003,69(1):616-624
We detected, for the first time, the occurrence of vegetative incompatibility between different isolates of the arbuscular mycorrhizal fungal species Glomus mosseae. Vegetative compatibility tests performed on germlings belonging to the same isolate showed that six geographically different isolates were capable of self-anastomosing, and that the percentage of hyphal contacts leading to fusions ranged from 60 to 85%. Successful anastomoses were characterized by complete fusion of hyphal walls, protoplasm continuity and occurrence of nuclei in the middle of hyphal bridges. No anastomoses could be detected between hyphae belonging to different isolates, which intersected without any reaction in 49 to 68% of contacts. Microscopic examinations detected hyphal incompatibility responses in diverse pairings, consisting of protoplasm retraction from the tips and septum formation in the approaching hyphae, even before physical contact with neighboring hyphae. Interestingly, many hyphal tips showed precontact tropism, suggesting that specific recognition signals may be involved during this stage. The intraspecific genetic diversity of G. mosseae revealed by vegetative compatibility tests was confirmed by total protein profiles and internal transcribed spacer-restriction fragment length polymorphism profiles, which evidenced a higher level of molecular diversity between the two European isolates IMA1 and BEG25 than between IMA1 and the two American isolates. Since arbuscular mycorrhizal fungi lack a tractable genetic system, vegetative compatibility tests may represent an easy assay for the detection of genetically different mycelia and an additional powerful tool for investigating the population structure and genetics of these obligate symbionts. 相似文献
9.
Vincenzo Carelli Felice Liberatore Antonio Casini Rosanna Mondelli Alberto Arnone Italo Carelli Giuseppe Rotilio Irene Mavelli 《Bioorganic chemistry》1980,9(3):342-351
The composition and the structure of the product from the known electrochemical dimerization of the NAD+ have been conclusively demonstrated. A detailed analysis of the 1H and 13C nmr spectra has in fact led to the conclusion that the product contains three diastereoisomeric dimers of the 4,4′-tetrahydrobipyridyl type. Furthermore, the cytoplasmic fraction obtained from a standard mitochondrial preparation of rat liver has been shown to catalyze the oxygen uptake by the dimers. A 1 : 1 molar ratio of the reagents in the redox process is indicated by manometric data on oxygen uptake complemented by spectrophotometric analysis of the oxidized substrates, suggesting that H2O2 is the reduction product. NAD+ was identified as the oxidation product by an enzymatic method. 相似文献
10.
J M Bernard H Gras-Masse H Drobecq A Tartar P Lefrancier A Hosmalin C Carelli L Chedid 《International journal of peptide and protein research》1987,29(4):455-463
Two glycopeptides associating the aminoacid sequence of LH-RH with MDP were prepared, using a Lys residue as a linker. These conjugates, N alpha MDP N epsilon (LH-RH)-Lys and N alpha MDP N epsilon (LH-RH)-Lys-NH2 obtained by condensation of fragments were synthesized by liquid as well as solid phase methods. Both compounds were able to induce anti LH-RH antibodies and immunological castration. They retained the immuno-adjuvant activity of MDP. Such antigen-adjuvant constructs, devoid of carrier and obtained by chemically defined and reproducible synthetic methods could offer suitable tools for structure-activity relationship studies aiming at defining synthetic vaccines. 相似文献