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1.
Doppler echocardiographic characteristics of normally functioningAllcarbon prostheses were studied in 149 consecutive patientswith 157 valves in the mitral (n=73) and aortic (n=84) positionswhose function was considered normal by clinical and echocardiographicevaluation. In the mitral position, the mean gradient and theeffective mitral orifice area were not significantly differentin either the 25-mm or the 31-mm size valves (from 5±1to 4±1 mmHg and from 2.2±0.6 to 2.8±0.9cm2, respectively; P=ns for both). Conversely, peak gradientwas significantly and inversely correlated to actual orificearea (r=–0.70; P<0.0006), decreasing from 15±3mmHg in the 25-mm size valve to 9±1 mmHg in the 31-mmsize. In the aortic position, the mean gradient was 29±8 mmHgin the 19-mm size valve; it decreased to 8±2 mmHg inthe 29-mm size. Effective prosthetic aortic valve area, calculatedusing the continuity equation, ranged between 0.9±0.1cm2 for the 19-mm size valve to 4.1±0.7 cm2 for the 29-mmsize. By analysis of variance, effective prosthetic aortic valvearea differentiated various valve sizes (F=25.3; P<0.0001)better than peak (F=5.34; P=0.012) or mean (F=4.34; P=0.0052)gradients alone, and it correlated better with actual orificearea (r=0.89, r=–0.70 and r=–0.65, respectively).This study provides the normal range for Doppler haemodynamiccharacteristics of the various sizes of the Allcarbon valvein the mitral and aortic positions so that prosthetic malfunctioncan be identified.  相似文献   
2.
Seventy-nine transitional cell carcinomas (TCCs) of the urinary bladder (25 grade 1, 22 grade 2, and 32 grade 3 tumours) were examined for p53 overexpression by immunohistochemistry with a monoclonal antibody and for human papillomavirus (HPV) infection by the polymerase chain reaction (PCR). Positive immunostaining for p53 was detected in 40·5 per cent of the cases; the percentage of positive cases was significantly lower in low-grade (G1 and G2) TCCs than in high-grade (G3) tumours (10·6 per cent vs. 84·4 per cent; P <0·0001). The overall rate of HPV infection was 32·9 per cent; 20·3 per cent of the cases were positive for HPV 16, 3·8 per cent for HPV 18, and 8·9 per cent for both. Consensus primers as well as type-specific primers for HPV types 6, 11, and 33 failed to detect any additional case with HPV infection. The prevalence of HPV 16 and/or HPV 18 infection was significantly higher in low-grade than in high-grade tumours (44·7 per cent vs. 15·6 per cent; P =0·0061). p53-positive cases were more common among papillary, deeply infiltrating tumours, and HPV-positive cases among papillary, non-infiltrating lesions. According to these data, p53 overexpression and HPV 16/18 infection are common findings in bladder TCC and there appears to be an inverse correlation of p53 overexpression and of HPV infection with tumour aggressiveness. The possibility of different molecular pathways in superficial low-grade and in invasive high-grade tumours is suggested.  相似文献   
3.
Cesinaro AM, Nannini N, Migaldi M, Pepe P, Maiorana A. Psoriasis vs allergic contact dermatitis in palms and soles: a quantitative histologic and immunohistochemical study. APMIS 2009; 117: 629–34. A systematic histologic and immunohistochemical study of cases of psoriasis (PSO) and allergic contact dermatitis (ACD) in palmo‐plantar skin was performed to find differences between these two diseases that usually show overlapping features in these specific sites. Skin biopsies from 42 (22 female, 20 male) patients were evaluated for several histopathologic parameters and immunohistochemistry was applied to quantify keratinocytic proliferation, the number of dendritic cells (DCs) and the phenotype of the mononuclear cell infiltrate. Regular epidermal hyperplasia and marked parakeratosis were found to be more frequent in PSO than in ACD cases, but only the first parameter reached the level of significance (p = 0.03). The number of S100 protein‐positive DCs was significantly higher in ACD (p = 0.006), whereas keratinocytic proliferation, studied with Mib‐1, was found to be higher in PSO than in ACD, but the difference was not statistically significant. No significant difference was detected in the number of CD4+, CD8+ and bcl2+ lymphocytes in PSO and ACD cases. In the palms and soles, the finding of irregular epidermal hyperplasia and the detection of a higher number of S100 protein‐positive DCs favor the diagnosis of ACD over PSO. The differential diagnosis between PSO and ACD can be practically approached using a histopathologic parameter and a commercially available antibody.  相似文献   
4.
ABSTRACT. The respiratory burst of polymorphonuclear leukocytes was investigated in 24 children with insulin dependent diabetes mellitus and 24 healthy controls. This oxygen dependent, membrane associated process generates a number of toxic oxygen metabolites which are implicated in the pathogenesis of endothelial damage. The activity of polymorphonuclear leukocytes was studied in terms of luminol amplified chemiluminescence. It was found that the resting luminol amplified chemiluminescence activity of isolated polymorphonuclear leukocytes from diabetic children was significantly higher than that of controls (342000±174000 cpm vs. 165000±82000 cpm, p <0.01). The addition of respiratory burst inhibitors caused a significant reduction of basal chemiluminescence (> 80%). When the ratio of phorbol myristate acetate stimulated activity to basal activity was calculated and used as an activation index, it was found to be significantly reduced in diabetics relative to controls (4.29 ± 2.46 vs. 8.34±3.21, p<0.01). These observations suggest that increased release of toxic oxygen metabolites from polymorphonuclear leukocytes in diabetic subjects may play a role in the development of diabetic angiopathies.  相似文献   
5.
The enzyme S-adenosylmethionine:protein carboxyl-O-methyl-transferase, type II (EC2.1.1.77; PCMT) from eukaryotes methyl esterifies peptides containing isoAsp residues, which can arise from spontaneous deamidation of labile Asn residues. We report here a study on in vitro methyl esterification of mouse EGF by bovine brain PCMT. This peptide contains two Asn in the sequences Asn1-Ser2 and Asn16-Gly17. It is known from the literature that the presence of a small residue on the carboxyl side of asparaginyl makes this residue susceptible to deamidation through the spontaneous formation of a succinimide intermediate. Therefore EGF was incubated under deamidating conditions (pH9.0, 37° for 48 h) and the extent of deamidation monitored by enzymatically measuring the NH3 produced during the alkali treatment: a release of 0.80 mol NH3/mol EGF was calculated. The alkali-treated EGF, analyzed by anion-exchange chromatography, shows two major components identified as native EGF (nEGF) and its deamidated form (dEGF). When incubated in the presence of purified PCMT neither nEGF nor dEGF showed any methyl accepting capability. Since it is known that the three-dimensional structure of a protein may hinder the methyl esterification of a potential ethyl accepting site, dEGF was unfolded by reducing and alkylating the intrachain disulfide bridges. Only a slight increase in the methyl accepting capability could be observed. Conversely, when EGF was deamidated after its unfolding, the resulting protein was stoichiometrically methylated by PCMT, presumably at level of isoAsp16. Our findings strongly suggest that the three-dimensional structure of a protein is a major specificity determinant for both deamidation and methyl esterification processes.  相似文献   
6.
Empirical results in the last 20 years have shown that employedwomen, on the whole, have a better perinatal outcome than full-timehousewives. The possible reasons for this difference are presentedand discussed Despite the consistency of the data, current thinkingin this area is still influenced by the idea that being outsidethe labour market may represent a protective factor in pregnancy.The obvious resistance, on the part of researchers, to fullyacknowledging results based on empirical data indicates thepersistence of the prejudice that sees housewives as women whodo not work. The fact of the matter is that they work full-time,often in poor conditions, and without a salary. The possibleconsequences of this prejudice for perinatal health are outlined.  相似文献   
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