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排序方式: 共有860条查询结果,搜索用时 15 毫秒
1.
Role of cellular retinoic acid binding protein (cRABP) in patients with large bowel cancer 总被引:1,自引:0,他引:1
G Di Fronzo V Cappelletti P Miodini L Bertario G Ravasi 《Cancer Detection and Prevention》1987,10(5-6):327-333
The presence of cellular retinoic acid binding protein (cRABP) was analyzed in 13 consecutive patients with large bowel cancer (one right colon and 12 rectum-sigmoid, classified as three Duke B, eight C, and two D). Specimens of neoplastic tissue and of adjacent mucosa were obtained at surgery, and cRABP was determined by an assay based on incubation of partially purified cytosol with labeled retinoic acid and ultracentrifugation in sucrose density gradients. Sixty-one percent of tumors contained detectable levels of cRABP, whereas 58.3% of normal mucosal specimens were positive for cRABP. Among the positive tumors 62.5% contained cRABP also in the corresponding mucosa; in the group of cRABP-negative tumors, 40% showed cRABP in the adjacent mucosa. No correlation could be established with the grading or the stage of the tumors; however, interestingly, 100% (three cases) of gelatinous carcinomas were cRABP positive. Since cRABP seems to be a character of neoplastic cells contrary to normal ones, it would be interesting to investigate the conditions that influence the presence of this protein in normal appearing mucosa adjacent to carcinoma. 相似文献
2.
M. Vincenzi T. Morlino P. Allegri E. Barbieri F. Cappelletti U. Delio R. Ometto P. Maiolino 《Clinical cardiology》1981,4(1):15-21
Alterations in cardiovascular function induced by the acute intravenous administration of verapamil (5 or 10 mg) in 52 patients (29 with ischemic heart disease and 23 without heart disease) were evaluated with use of invasive techniques (right and left heart catheterization, left ventricular cineangiography, and coronary arteriography). The most significant changes were represented by a decrease in systemic vascular resistance and systemic arterial pressure, and an increase in heart rate and cardiac output. Contractility indexes were not depressed in either group, and altered ventricular wall motion tended to improve to a slightly smaller degree than in patients treated with nitroglycerin. The use of verapamil in patients with ischemic heart disease appears to be safe, and concern about the negative inotropic influences in humans no longer seems justified. 相似文献
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emm Gene distribution among erythromycin-resistant and -susceptible Italian isolates of Streptococcus pyogenes 下载免费PDF全文
Zampaloni C Cappelletti P Prenna M Vitali LA Ripa S 《Journal of clinical microbiology》2003,41(3):1307-1310
The phenotypes and genetic determinants for macrolide resistance were determined for 167 erythromycin-resistant Streptococcus pyogenes strains. A cMLS phenotype was shown in 18% of the erythromycin-resistant strains, while inducible resistance was apparent in 31% and the M phenotype was apparent in 50%. The emm gene type of this set of resistant isolates and that of 48 erythromycin-sensitive isolates were determined. emm2 and emm48 were recorded only in the resistant strains of the M phenotype, while approximately all of the strains harboring the emm22 gene had the cMLS phenotype. More than 80% of the emm89-positive strains had the iMLS phenotype, and the same portion of emm4 strains presented the M phenotype. emm3 is recorded only among sensitive strains. The distribution of frequencies of the genetic determinant for the virulence factor M protein was significantly different both among organisms of different types of resistance and between resistant and sensitive populations of S. pyogenes under study. 相似文献
6.
L. Cagnoli P. Tabacchi Sonia Pasquali Marinella Cenci M. Sasdelli P. Zucchelli 《Clinical and experimental immunology》1982,50(1):70-76
Peripheral blood lymphocytes from 15 healthy controls and 59 patients with idiopathic glomerulonephritis were studied to determine whether an imbalance exists among human T cell subsets in these diseases. Twenty of the patients studied had a minimal change nephropathy (10 with nephrotic syndrome and 10 in sustained remission); 27 had a membranous glomerulonephritis (12 with nephrotic syndrome, six with isolated proteinuria and nine in complete remission); 12 patients had an IgA glomerulonephritis with heamaturia and mild proteinuria. Monoclonal antibodies directed at human T lymphocyte subsets termed OKT3, OKT4 and OKT8 were used in an indirect immunofluorescence assay in all cases. Patients with minimal change nephropathy, with or without nephrotic syndrome and patients with IgA glomerulonephritis showed mean values of OKT3+ cells (total peripheral T cells), helper OKT4+ cells, suppressor OKT8+ cells and OKT4+/OKT8+ cell ratio, in the normal range. Only the group of patients with membranous glomerulonephritis and nephrotic syndrome presented a mean OKT4+/OKT8+ ratio greater than the normal group (percentages: 2·43±0·3 vs 1·6±0·1 s.e.m.; P<0·02). This increased ratio was due to a reduction in the OKT8+ cell subset compared to the healthy subjects (percentages: 27·6±2·9 vs 36·8±1·4 s.e.m.; P<0·01). Our data shows that the functional lymphocyte disorders previously described in minimal change nephropathy and IgA glomerulonephritis are not due to a numerical imbalance of lymphocyte subsets. Such an imbalance of lymphocyte subsets was specifically observed in membranous glomerulonephritis with nephrotic syndrome. The true significance of this finding has to be clarified by longitudinal studies and functional tests. 相似文献
7.
Di Paolo N Bocci V Salvo DP Palasciano G Biagioli M Meini S Galli F Ciari I Maccari F Cappelletti F Di Paolo M Gaggiotti E 《The International journal of artificial organs》2005,28(10):1039-1050
BACKGROUND: Since 1990 our group has been using extracorporeal circulation to ozonate blood by an original method, known as extracorporeal blood oxygenation and ozonation (EBOO), with the aim of amplifying the results observed with ozone autohemotherapy. OBJECTIVE: To verify the hypothesis that EBOO improves the skin lesions typical of peripheral artery disease (PAD) patients. METHODS: Twenty-eight patients with PAD were randomized to receive EBOO or intravenous prostacyclin in a controlled clinical trial. The primary efficacy parameters were regression of skin lesions and pain,and improvement in quality of life and vascularisation. RESULTS: Patients treated with EBOO showed highly significant regression of skin lesions with respect to patients treated with prostacyclin. Other parameters that were significantly different in the two groups of patients were pain,pruritus, heavy legs and well-being. No significant differences in vascularisation of the lower limbs before and after treatment were found in either group.No side effects or complications were recorded during the 210 EBOO treatments. CONCLUSION: EBOO was much more effective than prostacyclin for treating skin lesions in PAD patients and also had a positive effect on patient general condition without any apparent change in arterial circulation. This suggests other mechanisms of action of EBOO. 相似文献
8.
Davide Serrano Chiara Pozzi Silvia Guglietta Bruno Fosso Mariano Suppa Patrizia Gnagnarella Federica Corso Federica Bellerba Debora Macis Valentina Aristarco Paolo Manghi Nicola Segata Cristina Trovato Maria Giulia Zampino Marinella Marzano Bernardo Bonanni Maria Rescigno Sara Gandini 《Nutrients》2021,13(2)
Obesity and diet are associated with colorectal cancer (CRC) risk, and microbiome could mediate this risk factor. To investigate this interaction, we performed a case–control study (34 CRC cases and 32 controls) and analyzed fecal microbiota composition using 16S rRNA metabarcoding and sub-sequential shotgun analyses of genomic bacterial DNA to evaluate the role of microbiome and diet in CRC etiology, taking into account vitamin D and other risk biomarkers. Dietary habits were evaluated using a short questionnaire. Multivariate methods for data integration and mediation analysis models were used to investigate causal relationships. CRC cases were significantly more often deficient in vitamin D than controls (p = 0.04); FokI and CYP24A1 polymorphism frequency were different between cases and controls (p = 0.03 and p = 0.02, respectively). A diet poor in fatty fish and rich in carbohydrates was found to be significantly associated with CRC risk (p = 0.011). The mediation analysis confirmed the significant role of the microbiome in mediating CRC risk—increasing levels of Bifidobacteria/Escherichia genera ratio, an indicator of “healthy” intestinal microbiome, can overcome the effect of diet on CRC risk (p = 0.03). This study suggests that microbiome mediates the diet effect on CRC risk, and that vitamin D, markers of inflammation, and adipokines are other factors to consider in order to achieve a better knowledge of the whole carcinogenic process. 相似文献
9.
Cytoskeletal proteins have been reported as constituents of cytoplasmic inclusions typical of degenerated neurones in Parkinson's disease and, in addition, the involvement of cytoskeleton in the mechanism of action of the parkinsonism-producing neurotoxin MPP+ is emerging. Here we investigate the influence of MPP+ on the dynamic behaviour of microtubules. Neurone-like cells derived from a rat pheochromocytoma cell line (PC12) and differentiated with nerve growth factor are used as a model system. We found that sublethal doses of the neurotoxin markedly affect the state of tubulin polymerisation: polymerised tubulins significantly decreased, whereas an increase of unpolymerised alpha-tubulin was observed. Since the concentration of unassembled tubulin directly regulates tubulin synthesis by a feedback mechanism, we studied alpha- and beta-tubulin synthesis by metabolic labelling of PC12 cells with [35S] methionine and following immunoprecipitations. The results showed the significant decrease of labelling in both the microtubule subunits in cells exposed to the neurotoxin. We suggest that the MPP+-induced imbalance of tubulin polymerisation and synthesis represents a novel early step in the mechanism of action of the neurotoxin. 相似文献
10.
A Di Massa R Cappelletti D Carriero O Pede A Cozzolino 《Minerva anestesiologica》1999,65(7-8):555-559
The aim of this work was to explain the reasons of two unsuccessful blocks of sciatic nerve even if anaesthetic solution was injected through insulated needle on elicited twitch. The clinical cases were two outpatients undergoing diagnostic arthroscopy of knee under anaesthetic block of sciatic and femoral nerves. In both patients, the muscular twitch appeared when the ischiatic bone was kept in unexpected touch with needle tip. In spite of the attempt to locate correctly the needle (the touch with bone means that the nerve is not in front of the needle tip), the injection of anaesthetic solution was unsuccessful. In clinical environment, when electroinsulated needles gathered total amount of administered current on the needle tip, it was not possible to elicit a twitch just at the moment of touch of the needle with the bone. Referred events disagree with some experimental works performed out of clinical environment, which found that total amount of administered current through an insulated needle gathers always in front of the tip. Our clinical observations seems to confirm an electrolocation mistake called "electrical shadow". The ability of sheathed needles to work as occasional capacitor due to the alternation of two conductor layers (needle shaft and tissue) and of a dielectric (coating material) can explain some missing electrolocations, as the appearance of electric fields within dielectric needle sheathing. 相似文献