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11.
S Di Giovanni G Valentini E Ravazzolo P Carducci P Giallonardo C Maschio 《The International journal of biological markers》1987,2(3):169-172
Beta-2-microglobulin concentrations were determined in serum samples from 45 patients with benign and malignant monoclonal gammopathies. In the group of patients suffering from multiple myeloma or Waldenstr?m macroglobulinemia the mean beta 2-microglobulin level was significantly higher than in the group with monoclonal gammopathy of undetermined significance. Values above 3 mg/L were highly indicative of a neoplastic process and were observed in all the Waldenstr?m patients and in greater than 90% of myeloma patients. No significant correlation was noticed between beta 2-microglobulin and monoclonal protein levels in any of the groups examined. 相似文献
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Mapping of a restriction fragment length polymorphism within the human aldolase B gene 总被引:1,自引:0,他引:1
Giovanni Paolella Rita Santamaria Pasqualina Buono Francesco Salvatore 《Human genetics》1987,77(2):115-117
Summary Peripheral blood DNA was hybridized to the full-length cDNA and the cloned structural gene of human aldolase B. With PvuII endonuclease a restriction fragment length polymorphism was detected that was present in the heterozygous state in about 21% of the individuals tested. A map of the human aldolase gene was constructed for the two groups of individuals found to produce different fragments after PvuII digestion. This allowed the localization of the polymorphic site within the gene, which was found to be due to the loss of a PvuII site in the last intron upstream from the 3 end. This polymorphism may be used as a genetic marker to study individuals affected by hereditary fructose intolerance. 相似文献
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C T Evans D Owens J P Casazza P A Srere 《Biochemical and biophysical research communications》1989,164(3):1437-1445
The DNAs encoding the non-mutant and mutant forms of pig citrate synthase (PCS) were subcloned into an expression system to determine their synthesis and stability in E. coli gltA- cells that are defective in bacterial citrate synthase. GltA- cells that expressed the non-mutant PCS DNA grew on defined minimal acetate media and produced a constant level of PCS (0.43 U/mg protein). In contrast, when the gltA- cells were transformed with the DNA encoding PCS mutations in His274 or Asp375 the cells did not grow on minimal acetate media. The presence of the mutant PCS proteins in E. coli was confirmed by protein blot and immunoisolation analyses using an antibody specific for porcine heart citrate synthase. The activities of the mutant PCS enzymes were two orders of magnitude less than the non-mutant enzyme in the total cell lysates. The data indicate that the active site amino acids, His274 and Asp375, are essential for the catalysis activity of citrate synthase. 相似文献
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Giovanni Savettieri Rosa Guarneri Giuseppe Salemi Vincenzo La Bella Donatella Ferraro Salvatore Scondotto Federico Piccoli 《Neurochemical research》1990,15(8):773-776
[3H]Flunitrazepam (FNZ) binding to cortical neurons from fetal rat brain was investigated in vitro. The use of a synthetic medium specific for neurons made it possible to plot a developmental curve of3H-FNZ binding in an almost pure neuronal culture. Detectable specific binding was present in vitro at time 0 (that is, the 16th gestational day). A progressive increase of binding, due to an increment in the number of recognition sites, was observed on the subsequent days. The affinity of the specific binding sites to3H-FNZ was enhanced by the addition of exogenous GABA, whereas the density was not affected. 相似文献
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Giovanni Bernardini Pio Belgiojoso Marina Camatini 《Molecular reproduction and development》1988,21(4):403-408
The motility status of Xenopus laevis spermatozoa does not affect their respiration rate. Oxygen consumption for 109 spermatozoa is approximately 0.4 μmol/minute. Oxygen consumption is not increased by gramicidin D, an uncoupler, and it is not blocked by KCN or NaN3. The adenosine triphosphate (ATP) content of spermatozoa that have been activated is definitely less than that in the spermatozoa that remained immotile. Incubation in KCN, NaN3, and gramicidin decreases the ATP content and impairs motility. The conclusions of the present study are that in Xenopus spermatozoa motility and oxygen consumption are not correlated, and the composition of the respiratory chain of these spermatozoa presents noteworthy peculiarities. 相似文献
20.
Susanna Voltolini Giovanni Orengo Luigi Fontana Arsenio Corrado Negrini 《Aerobiologia》1992,8(3):349-354
Summary Fifty workers from two grain elevator terminals were examined to evaluate the prevalence of respiratory symptoms and their relationship with grain dust exposure.Fifty per cent of subjects complained of respiratory symptoms (rhinitis, asthma, chronic cough and dyspnea on exertion). In 34% of the workers the ventilatory function revealed some abnormalities (slight or moderate obstruction).Twenty-two (44%) showed a positive cutaneous reaction to one or more of the allergens tested, mostly towardsDermatophagoides and storage mites. The self-measurement of PEF over 14 days in 27 workers, showed significant differences between symptomatic and asymptomatic subjects. In particular, the results obtained from the cutaneous reactions could suggest a bronchial hypereactivity, worsened by the working exposure to dusts. The monitoring of PEF appears to be a simple and useful method for investigating the relationship between respiratory symptoms and the working environment. 相似文献