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41.
Claudia Giaroli Gianfranco Riccò Gianni Vecchi Stefano Belli Caterina Bruno Mario Grignoli Silvia Candela Salvatore Minisci Roberto Poletti Guiseppina Venturi Antonio Ziccardi Pietro Comba 《International archives of occupational and environmental health》1994,66(1):7-11
The present study describes cause-specific mortality of asbestos cement workers in the Emilia Romagna region of Italy. The cohort included workers in ten factories, most of which started operating between 1955 and 1965. Asbestos, mainly chrysotile, constituted 10%–20% of the dry component of the mixture. Crocidolite range between 5% and 50% of total asbestos. Asbestos concentrations up to 44 ff/cc were reported prior to 1975, while in recent years they have usually been below 0–1 ff/cc. The cohort included 3341 workers who had at some time been employed in the ten factories under study. Their mortality experience was compared with that of the population resident in Emilia Romagna. Vital status was ascertained at 1989. Seventy-three subjects were lost to followup (2.2%). Mortality from all causes and from all types of cancer was increased in the cohort. Malignant neoplasms of the respiratory tract showed a significant increase (SMR: 134; 90% confidence interval: 101–175; 40 observed) due to lung cancer (SMR: 124; 90% confidence interval: 91–166; 33 observed) and neoplasms of the pleura, mediastinum, and other parts of the respiratory tract (SMR: 602; 90% confidence interval 237–1267; 5 observed). The discrepancy between observed and expected mortality mainly concerned subjects with at least 20 years of employment in the factories. Five more cases of histologically confirmed mesothelioma occurred after the end of follow-up. 相似文献
42.
Bone mineral content (BMC) and testosterone levels were evaluated and compared in 10 hypogonadal males and 10 normal, age-matched controls. In 6 of the subjects an investigation was also carried out into the effects of testosterone administration on lumbar BMC, calcitonin (CT) response to hypercalcaemia, osteocalcin (BGP) and the fasting urinary calcium/creatinine and hydroxyproline/creatinine ratios. Our results confirm that male hypogonadism is characterized by a low BMC and that testosterone administration is able to improve this parameter and to increase both basal BGP and CT response to hypercalcaemia. Testosterone therefore probably acts on bone tissue through both a direct action on osteoblast cells and an improvement in CT secretion. 相似文献
43.
A. Di Stefano M. Wittner B. Corman 《Pflügers Archiv : European journal of physiology》1991,419(3-4):327-331
The maximal urinary osmolality that can be reached by the kidney is reduced with age. This may be due to impaired NaCl transport by the medullary thick ascending limb of Henle's loop, which is part of the renal concentrating mechanism and is modulated by antidiuretic hormone (ADH). We therefore tested in vitro a possible age-related change in the transport capacity and in the response of this nephron segment to ADH in young (1–2 months) and old (20–24 months) mice. The transepithelial potential difference (V
te) was significantly higher in young mice (+8.5±0.4 mV, n=13) than in old ones (+6.6±0.5 mV, n=17). Addition of 0.1 nmol.l–1 ADH to the bath solution significantly increased V
te by 5.2±0.5 mV in the young and by 3.1±0.6 mV in the old animals. Application of dibutyryl-cAMP (0.1 mmol.1–1) did not further increase the hormonal response in both groups. The ADH-mediated increase in the corresponding equivalent short-circuit current (I
SC = V
te/Rte) was twice as great in young mice as in old, indicating that the stimulation of NaCl transport by ADH across the medullary thick ascending limb is significantly reduced with age. These results suggest that the previously reported age-related defect in the urinary concentrating ability of the kidney is partly due to a decreased response of the medullary thick ascending limb to ADH. 相似文献
44.
The authors have reviewed their experience with treatments of small intracranial lesions by unconventionally fractionated stereotactic radiotherapy using a 4 MV photon beam. Treatment is carried out by multiple non coplanar arc irradiation obtained rotating the target, while kept at the isocentre of a Linac, around a vertical axis. The outmost concentration of the dose within the target volume enables consistent reduction of the amount of the absorbed dose by critical structures of the intact brain. They analyse the dose distribution and the method to optimise the choice of the therapeutic dose. Finally, some radiobiological considerations are presented. 相似文献
45.
The goal of this classification of bone defects related to dental implant placement is to help clinicians accurately discuss proposed treatment regimens and organize treatment for clinical correction. A further goal of this effort to categorize bone defects requiring bone augmentation for implant placement is to standardize terminology to allow for more accurate dental communication. The 5 most encountered categories of bony defects are described. 相似文献
46.
Alberto Falchetti Marco Di Stefano Francesca Marini Francesca Del Monte Carmelo Mavilia Debora Strigoli Maria L De Feo Giovan Isaia Laura Masi Antonietta Amedei Federica Cioppi Valentina Ghinoi Susanna Maddali Bongi Giuseppina Di Fede Carmela Sferrazza Giovan B Rini Daniela Melchiorre Marco Matucci-Cerinic Maria L Brandi 《Journal of bone and mineral research》2004,19(6):1013-1017
PDB is genetically heterogeneous. Mutations of the sequestosome1 gene have been reported in sporadic and familial forms of Paget's in patients of French Canadian and British descent. Mutational analyses in different ethnic groups are needed to accurately investigate hereditary diseases. We describe two novel mutations of sequestosome1 in 62 Italian sporadic patients, confirming the role of the encoded protein in this disorder. INTRODUCTION: Paget's disease of bone (PDB) is a relatively common disease of bone metabolism reported to affect up to 3% of whites over 55 years of age. The disorder is genetically heterogeneous, and at present, there is scientific evidence that at least eight different human chromosomal loci are correlated with its pathogenesis. Mutations of the sequestosome1 (SQSTM1) gene were identified as responsible for most of the sporadic and familial forms of Paget in patients of French Canadian and British descent. Such mutations were located at exon 7 and 8 levels, encoding for the ubiquitin protein-binding domain (UBA) and representing a mutational hot spot area. MATERIALS AND METHODS: To verify the involvement of this gene in Italian subjects affected by PDB, we performed mutational analysis in 62 sporadic PDB cases. RESULTS: We described three different mutations at exon 8 level: P392L, already described in the French Canadian population and families predominantly of British descendent, and two novel mutations consisting of the amino acid substitutions M404V and G425R. No significant differences in the clinical history of PDB have been observed in patients with SQSTM1 mutations in respect to those without. CONCLUSIONS: Even though our findings suggest a minor involvement of the SQSTM1 gene in the pathogenesis of sporadic Italian Paget's cases, the identification of different significant mutations within the SQSTM1 gene in unrelated, but clinically similar individuals, offers extremely convincing evidence for a causal relationship between this gene and PDB. Longitudinal studies are needed to assess the penetrance of genotype/phenotype correlations. Our findings confirm the evidence of a clustered mutation area at this level in this disorder. 相似文献
47.
Inflammatory biomarkers in blood of patients with acute brain ischemia 总被引:11,自引:0,他引:11
S. Sotgiu B. Zanda B. Marchetti M. L. Fois G. Arru G. M. Pes F. S. Salaris A. Arru A. Pirisi G. Rosati 《European journal of neurology》2006,13(5):505-513
Although many failed surrogate markers are provided in the literature, inflammation may contribute to the outcome of ischemic stroke. In 50 consecutive patients with acute ischemic stroke, in the absence of symptoms and signs of concomitant infection, we evaluated a panel of biomarkers reported to be variably associated with brain ischemia, and correlate their serum level with the brain lesion volume and clinical outcome. Infarct size was calculated on computed tomography (CT) scans by means of the Cavalieri's method. Neurological impairment was scored by using the Glasgow Coma Scale, Glasgow Outcome Scale and National Institutes of Health (NIH) scales at stroke onset and 3-month follow-up. Some markers showed a direct significant correlation with both initial and final NIH scale and with infarct size, particularly tumor necrosis factor alpha (TNF-alpha) (P=0.002), intercellular adhesion molecule-1 (P<0.01) and matrix metalloproteinase-2/9 (P=0.001). In contrast to previous reports, interleukin-6 (IL-6) serum level showed a significant inverse correlation with both final neurological impairment and infarct size (P<0.001). This novel finding allows us suggesting that IL-6, in the context of a complex pro-inflammatory network occurring during stroke, is associated with neuroprotection rather than neurotoxicity in patients with ischemic brain injury. 相似文献
48.
Enrico Verrina Barbara Andreetta Sergio Bassi Roberto Bonaudo Domenica A. Caringella Alfonso Castellani Pierluigi Cavalli Alberto Edefonti Giancarlo Lavoratti Luigi Longo Ivana Pela Rosa Penza Francesco Perfumo Virgilio Petrucci Marina Picca Mauro Ragaiolo Stefano Rinaldi Gianfranco Rizzoni Palma Sorino Giusto Viglino Graziella Zacchello Rosanna Gusmano 《Pediatric nephrology (Berlin, Germany)》1992,6(1):78-81
The results of the first 3 year' collaboration of the Italian Registry of Paediatric Chronic Peritoneal Dialysis (CPD) (1986–1988) are presented. This Registry acquired data on the majority of the paediatric patients treated with CPD in Italy, thus providing a national picture in a field where few nationwide surveys are available. Patients of less than 15 years of age at the start of dialysis were enrolled and clinical data collected until the age of 19 years. The number of nephrological paediatric centres participating in the Registry increased from 7 in 1986 to 11 in 1988. The total number of patients on CPD was 70 and the percentage of dialysed children treated with CPD ranged from 40.2% to 43.6%. Data on 89 peritoneal catheters were collected: during 1417 dialysis-months 70 catheter-related complications were observed (1:20.8 dialysis-months); actuarial catheter survival was 92.7% at 6 months, 84.8% at 1 year and 68.8% at 2 years. The incidence of peritonitis changed from 1 episode every 10.9 patient-months in 1986 to 1 every 19.8 in 1988. Abdominal hernias were the other main clinical complication observed. The survival of patients was 92.5% at 3 years, while the technique survival at the same time was 84%. 相似文献
49.
E Criado A A De Stefano B A Keagy G R Upchurch G Johnson 《Surgery, gynecology & obstetrics》1992,175(2):135-140
Infection of the foot is a limb threatening condition for patients with diabetes mellitus. Identification of patients with diabetes and severe infection of the foot most likely to benefit from early revascularization or major amputation would improve the results of a treatment policy to prevent limb loss and avoid futile delays in amputation. During a nine year period, 79 diabetic patients underwent emergency procedures for severe infection of the foot during the initial hospitalization period. None of the patients underwent arterial reconstruction. Eventually, 21 of the patients required a major amputation, eight during the initial hospitalization and 13 on a subsequent admission. Stepwise discriminant analysis of clinical independent variables revealed that the patients most likely to require a major amputation during the initial hospitalization were those with an absent dorsalis pedis pulse and a polymicrobial infection (p = 0.018). The overall amputation rate (immediate or subsequent amputation) was higher for patients of either sex with nonpalpable pedal pulses when compared with those with at least one palpable pulse (p less than 0.05). Males who were not dependent on insulin had the highest risk of overall limb loss (p = 0.01). Patients undergoing delayed amputation required a significantly higher number (p = 0.01) of readmissions to the hospital for recurrent infection of the foot than those who did not undergo amputation. Data in the current study suggest that early major amputation in a subset of patients would prevent delay in the rehabilitation process of the amputee, decrease long term morbidity and reduce health care cost. An aggressive policy of early revascularization in patients with a pulse deficit may reduce the amputation rate in those with diabetes with severe infection of the foot. 相似文献
50.
E Orlando S Cortelazzo M Marchetti R Sanfratello T Barbui 《Thrombosis and haemostasis》1992,68(5):495-499
Platelet adhesion to collagen under flow conditions was studied in 18 patients with lupus anticoagulant, seven of which showed a prolonged bleeding time in the presence of a normal platelet count. The effect of patient plasma, IgG and purified anticardiolipin antibodies on platelet adhesion was also examined. We found a significant reduction of platelet adhesion in patients with lupus anticoagulant, which was more evident in patients with prolonged bleeding time. This platelet adhesion defect could be attributed to a plasma factor. In fact, patients' platelets regained normal adhesion when mixed with normal plasma, whereas controls' platelets showed abnormal adhesion in the presence of patient plasma. A causative role of antiphospholipid antibodies was demonstrated in experiments using purified immunoglobulins and anticardiolipin antibodies. 相似文献