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排序方式: 共有227条查询结果,搜索用时 31 毫秒
1.
M R Giovagnoli P Di Fraia A Manna V Marafini C Valli P Marchei A Vecchione 《The International journal of biological markers》1989,4(1):13-17
We tested the presence of tumour polypeptide antigen (TPA) in lower urinary tract cells from 59 workers exposed to known bladder carcinogens and from 30 control subjects. We then correlated immunocytological expression and serum TPA levels. Lower urinary tract cells from 31 subjects gave either moderately or strongly positive immunocytological stains. Five also had high serum TPA. The detection of TPA by cytology and in serum differed significantly in workers exposed to cancer agents and the control group. 相似文献
2.
M Gascon-Barré S Vallières P M Huet 《Canadian journal of physiology and pharmacology》1986,64(6):699-702
The hepatic uptake of the hormone 1,25-dihydroxyvitamin D3 has been studied, in vivo, using the multiple indicator dilution technique. The fractional uptake of 1,25-dihydroxyvitamin D3 during a single circulatory passage across the dog liver has been estimated at 34.4 +/- 3.3% while its hepatic clearance was estimated at 364.3 +/- 94.1 mL/min. The hepatic uptake of 1,25-dihydroxyvitamin D3 is discussed in relation to its systemic bioavailability following intravenous or oral administration as well as in relation to the hepatic uptake of other vitamin D sterols; it is postulated that the hepatic uptake of vitamin D sterols does not seem to be mediated by specific receptors on the liver plasma membrane; it seems, however, that the hepatic uptake of vitamin D sterols may be inversely related to their relative affinity for the circulating carrier, the vitamin D binding protein. 相似文献
3.
The purpose of this study was to determine the influence of metabolic stresses, such as endurance training and chronic isoproterenol treatment, on skeletal muscle sensitivity to norepinephrine. Using an isolated perfused rat hindlimb preparation, dose-response curves for skeletal muscle oxygen consumption (VO2) and vascular resistance were obtained with control, endurance trained, and isoproterenol treated rats. No significant difference was found between control and experimental groups for non-stimulated VO2. In response to NE infusion, trained rats showed a significantly greater increase in VO2 compared to control rats while the response of the isoproterenol treated rats was of the same magnitude as the one for their respective control rats. At the highest dose of NE infused, the vasopressor response was significantly lower in trained rats compared to control rats. At none of the doses was there a significant difference in the vasopressor response between control and isoproterenol treated rats. These results suggest that repeated exposures to high levels of catecholamines, as produced during endurance training, leads to an increased sensitivity of skeletal muscle to the effect of norepinephrine. 相似文献
4.
Biological Trace Element Research - The results of a research in progress at the Istituto di Fisica Generale Applicata—University of Milan—on natural and anthropogenic elements'... 相似文献
5.
J Rajan K Valli R E Perkins F S Sariaslani S M Barns A-L Reysenbach S Rehm M Ehringer N R Pace 《Journal of industrial microbiology & biotechnology》1996,16(5):319-324
Four bacterial strains that use picric acid as their sole carbon and energy source were isolated. Mineralization of14C-UL-picric acid showed that up to 65% of the radioactivity was released as14CO2. HPLC and UV/Vis spectral analyses indicated complete degradation of picric acid by these organisms. HPLC and LC/MS analyses showed transient formation of 2,4-dinitrophenol during picric acid degradation. Degradation of picric acid was concomitant with stoichiometric release of three moles of nitrite per mole of picric acid. The four picric acid degraders were identified as close relatives ofNocardioides simplex (ATCC 6946) based on their small subunit (16S) rRNA gene sequences.This is contribution 7167 from Central Research & Development, Dupont Co, Wilmington, DE 19880, USA 相似文献
6.
Z Q Wu D Piché S Vallières P M Huet M Gascon-Barré 《Canadian journal of physiology and pharmacology》1991,69(3):426-436
To test further the competence of the cirrhotic liver to metabolize xenobiotics, hepatocytes were isolated from control and CCl4-induced cirrhotic male or female rats. Histologically micronodular cirrhosis was present in all CCl4-treated rats, while control rats had normal livers. Portal perfusion pressure and intrahepatic collagen content were also significantly increased by CCl4 administration. In male rats, no significant differences in levels of circulating transaminases nor in alkaline phosphatase was observed between cirrhotic and control rats, while CCl4-treated females had slightly higher than normal serum transaminase levels at the time of the studies. Hepatocytic cytochrome P-450 and basal xenobiotic biotransformation were unaffected by micronodular cirrhosis in both genders; calculation of the aminopyrine and 7-ethoxycoumarin intrinsic clearances (Cli) revealed, however, a slightly decreased transformation potential in hepatocytes obtained from cirrhotic females, a phenomenon not observed in cirrhotic male rats. It is speculated that the observed reduction in Cli may have been independent of cirrhosis per se, owing to the perduring cytotoxic effect of CCl4 as evidenced by the higher than normal level of transaminases in female rats. Finally, male rats were subjected to in vivo administration of phenobarbital or 3-methylcholanthrene; both compounds led to significant induction of the mixed-function oxidase system, which was similar in magnitude and in selectivity in control and cirrhotic rats as illustrated by calculation of the Michaelis-Menten kinetic parameters for aniline p-hydroxylation, aminopyrine-N-demethylation, 7-ethoxycoumarin-O-deethylation, and p-nitrophenol UDP-glucuronyl transferase. We conclude that in well-established but compensated and hepatolysis-free micronodular cirrhosis, hepatocytes are fully able to transform xenobiotics and to respond normally and selectively to inducers of drug metabolism. 相似文献
7.
8.
Giulia Borgonovo Eleonora Paulicelli Deborah Daniele Stefano Presilla Antonella Richetti Mariacarla Valli 《Reports of Practical Oncology and Radiotherapy》2022,27(4):717
BackgroundThe aim of our study is to determine whether deep inspiration breath hold (DIBH) is effective for reducing exposure of the heart, left coronary artery (LAD) and both lungs in right breast radiotherapy.Materials and methodsWe have analyzed 10 consecutive patients with right-sided breast cancer (BC), simulated during free breathing (FB) and in DIBH modality. For all patients we contoured breast PTV and organs at risk (right and left lungs, heart, LAD) on both CT scans (FB and DIBH). Finally, 5 patients were treated with IMRT and 5 with VMAT techniques.ResultsAll patients were able to end the treatments in DIBH modalities regardless of the longer treatment time in comparison to FB. The maximum and mean dose to the heart are lower in the DIBH modality. The mean values of the heart mean dose were 1.76 Gy in DIBH and 2.19 Gy in FB. The mean heart maximum dose in DIBH and FB were, respectively, 9.3 Gy and 11 Gy. Likewise, the maximum dose to the LAD is lower in DIBH; 2.57 Gy versus 3.56 Gy in FB. Noteworthy, 3 patients with hepatomegaly treated with the DIBH technique showed a higher ipsilateral lung dose than FB, but a decrease of liver dose.ConclusionWe report that the use of DIBH for right-sided BC allows the dose to the heart, LAD and to the liver to be reduced in case of hepatomegaly. This technique is well tolerated by patients, when adequately trained, and could be considered effective even in right sided BC. 相似文献
9.
C Ferrari M Pilli A Penna A Bertoletti A Valli A Cavalli G Pasetti F Fiaccadori 《Journal of virology》1992,66(4):2536-2540
Processing and presentation by T cells appear to be limited to antigens that can directly interact with the T-cell surface, thereby overcoming the T-cell inefficiency in antigen capture and internalization. Our study provides evidence that the hepatitis B virus (HBV) envelope proteins can also be efficiently processed and presented by CD4+ and CD8+ T cells to other T cells in a human leukocyte antigen class II-restricted fashion. This phenomenon suggests a receptor-mediated interaction between T cells and the HBV envelope and defines a system that can, we hope, be exploited for the identification of the receptor binding site within the HBV envelope and for the characterization of the putative cellular HBV receptor. 相似文献
10.
Stefania Trazzi Claudia Fuchs Emanuele Valli Giovanni Perini Renata Bartesaghi Elisabetta Ciani 《The Journal of biological chemistry》2013,288(29):20817-20829
Intellectual disability in Down syndrome (DS) appears to be related to severe proliferation impairment during brain development. Recent evidence shows that it is not only cellular proliferation that is heavily compromised in DS, but also cell fate specification and dendritic maturation. The amyloid precursor protein (APP), a gene that is triplicated in DS, plays a key role in normal brain development by influencing neural precursor cell proliferation, cell fate specification, and neuronal maturation. APP influences these processes via two separate domains, the APP intracellular domain (AICD) and the soluble secreted APP. We recently found that the proliferation impairment of neuronal precursors (NPCs) from the Ts65Dn mouse model for DS was caused by derangement of the Shh pathway due to overexpression of patched1(Ptch1), its inhibitory regulator. Ptch1 overexpression was related to increased levels within the APP/AICD system. The overall goal of this study was to determine whether APP contributes to neurogenesis impairment in DS by influencing in addition to proliferation, cell fate specification, and neurite development. We found that normalization of APP expression restored the reduced neuronogenesis, the increased astrogliogenesis, and the reduced neurite length of trisomic NPCs, indicating that APP overexpression underpins all aspects of neurogenesis impairment. Moreover, we found that two different domains of APP impair neuronal differentiation and maturation in trisomic NPCs. The APP/AICD system regulates neuronogenesis and neurite length through the Shh pathway, whereas the APP/secreted AP system promotes astrogliogenesis through an IL-6-associated signaling cascade. These results provide novel insight into the mechanisms underlying brain development alterations in DS. 相似文献