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11.
Simone Ottonello Giovanni Maraini Mario Mammi Hugo L. Monaco Paola Spadon Giuseppe Zanotti 《Journal of molecular biology》1983,163(4):679-681
Crystals of human plasma retinol-binding protein have been obtained from 4.5 m-NaCl buffered at pH 6.8 with 20 mm-cacodylate. The crystals are trigonal with space group R3 and unit cell dimensions, referred to the hexagonal system. . The crystals diffract to a resolution of 2.0 Å. 相似文献
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Fabrizio Villani Milena Galimberti Elena Monti Francesco Piccinini Enrica Lanza Annalinda Rozza Luigia Favalli Paola Poggi Franco Zunino 《Free radical research》1990,11(1):145-151
The effects of two sulfhydryl compounds, glutathione (GSH) and N-acetylcysteine (NAC), on the cardiotoxicity of doxorubicin (DXR) were tested on in vitro and in vivo models. DXR was administered to rats as 4 weekly i.v. doses of 3mg/kg. GSH (1.5 mmoles/kg), given i.v. 10 min before and 1 hr after DXR, was found to prevent the development of the delayed cardiotoxic effects of DXR, as assessed by electrocardiographic and mechanical parameters, as well as by histological examination of left ventricular preparations. In contrast, equimolar oral doses of NAC (1 hr before and 2hrs after DXR) were found to be ineffective. Both GSH and NAC prevented the negative inotropic effect produced by DXR on isolated rat atria. A good correlation exists between the cardioprotective effects of the two agents and their ability to enhance the non-protein sulfhydryl group content of the myocardium. Differences observed in vivo between GSH and NAC might be accounted for by pharmacokinetic factors. 相似文献
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Jose Pontón Fernando L. Hernando Maria Dolores Moragues Pedro L. Barea Mara Gerloni Stefania Conti Paola Fisicaro Cristina Cantelli Luciano Polonelli 《Mycopathologia》1996,133(2):89-94
The presence of heat shock mannoproteins (HSMPs) reactive with sIgA was demonstrated in several C. albicans strains. The subculture of the C. albicans isolated from mucosal surfaces on Sabouraud's dextrose agar at 25 °C switched off the HSMP expression. A re-expression of the HSMPs was obtained in the same medium by shifting the temperature of incubation to 37 °C. However, expression of HSMPs in two strains isolated from deep infections was maintained during several subcultures on Sabouraud's dextrose agar at 25 °C. A glycoprotein of 200 kDa seemed to be the main HSMP reacting with vaginal sIgA. The data presented in this study suggest that factors other than temperature can influence the expression of C. albicans HSMPs and therefore these antigens should be referred as stress mannoproteins.Abbreviations HSMPs
heat shock mannoproteins
- MAb
monoclonal antibody
- sIgA
secretory IgA 相似文献
15.
David Bouchez Paola Vittorioso Béatrice Courtial Christine Camilleri 《Plant Molecular Biology Reporter》1996,14(2):115-123
We have designed a new method for the recovery of T-DNA flanking sequences from T-DNA-tagged lines ofArabidopsis thaliana. Since most transformation vectors in use contain a plant-selectable marker for kanamycin resistance, we can use the 3′ part
of thenptII coding region from the T-DNA to complement the bacterial 5′ region of thenptII gene from Tn5 to reconstruct a functional kanamycin-resistance gene inEscherichia coli. We have constructed a vector that contains the 5′ part of thenptII gene from Tn5 up to the uniquePst I site. By cloning total DNA from transformed lines in this vector, we were able to select directly for clones containing
a T-DNA fragment, which reconstitutes a functional kanamycin gene, and a fragment of arabidopsis genomic DNA adjacent to the
insertion. Flanking sequences up to 4 kb were rescued by this system. 相似文献
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Testicular weight and DNA content were markedly reduced (63 and 69%) in weanling Long-Evans rat pups rendered hypothyroid from birth by administration of propylthiouracil (PTU), a reversible goitrogen. These growth deficits worsened to >80% by continuing hypothyroidism beyond weaning, to days 50 and 90. Recovery of thyroid function, brought about by discontinuing PTU at weaning, resulted in a paradoxical stimulation of testis growth, amounting to increased weight (40%), DNA content (60%) and size by 90 days, compared to age-matched controls. In the 25-day or older hypothyroid rats, testicular structure was immature and spermatogenesis markedly delayed, as evident by closed lumen and significantly reduced diameter of seminiferous tubules (38%), thickness of germinal layer (70%), and number of primary spermatocytes (86%), compared to control. Hypothyroidism did not alter the number of tubules per testis cross section. In the 90-day recovery rats, numbers of seminiferous tubules were unchanged but tubular diameter was significantly (20%) larger than in controls and spermatogenesis appeared very active as indicated by significantly increased germinal layer thickness (22%) and total number and density of primary spermatocytes (55% and 40%). The results show that although postnatal hypothyroidism is deleterious for testicular growth and spermatogenesis, recovery from this condition leads to enhanced seminiferous tubular growth and spermatogenesis. 相似文献
19.
Lucia Potenza Antonella Amicucci Ismaela Rossi Francesco Palma Roberta De Bellis Paola Cardoni Vilberto Stocchi 《Biotechnology Techniques》1994,8(2):93-98
Summary Different species of truffle were studied in order to identify species-specific markers. The isolation of two Tuber magnatum Pico markers is reported. One of these could be used as a probe in dot blot hybridization, allowing the development of a rapid test able to identify Tuber magnatum species. 相似文献
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