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61.
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
62.
Dusica Maysinger Mario Herrera-Marschitz Michel Goiny Urban Ungerstedt A. Claudio Cuello 《Brain research》1992,577(2):300-305
The effects of intraventricular nerve growth factor (NGF) or saline treatments on extracellular acetylcholine (ACh), dopamine (DA) and adenosine (Ade) levels in the cortex and striatum of rats with unilateral devascularizing cortical lesions were studied in vivo with microdialysis. The devascularizing cortical lesion produced a decrease in extracellular ACh levels in both cortex and striatum as compared to those in normal rats, while the NGF treatment produced a significant increase in ACh levels in both regions. NGF could even increase cortical ACh levels in normal rats. The cortical lesion produced a decrease in extracellular DA in the cortex, while the NGF treatment appeared to reverse this effect. No significant changes in DA were observed in the striatum. The present study gives evidence that a unilateral cortical devascularizing lesion leads to changes in extracellular ACh and DA levels in cortex and striatum and that these changes could be reversed with intraventricular NGF treatment. 相似文献
63.
Genetic ablation of the t-SNARE SNAP-25 distinguishes mechanisms of neuroexocytosis. 总被引:12,自引:0,他引:12
Philip Washbourne Peter M Thompson Mario Carta Edmar T Costa James R Mathews Guillermina Lopez-Benditó Zoltán Molnár Mark W Becher C Fernando Valenzuela L Donald Partridge Michael C Wilson 《Nature neuroscience》2002,5(1):19-26
Axon outgrowth during development and neurotransmitter release depends on exocytotic mechanisms, although what protein machinery is common to or differentiates these processes remains unclear. Here we show that the neural t-SNARE (target-membrane-associated-soluble N-ethylmaleimide fusion protein attachment protein (SNAP) receptor) SNAP-25 is not required for nerve growth or stimulus-independent neurotransmitter release, but is essential for evoked synaptic transmission at neuromuscular junctions and central synapses. These results demonstrate that the development of neurotransmission requires the recruitment of a specialized SNARE core complex to meet the demands of regulated exocytosis. 相似文献
64.
†Francesco Mari Carlo Di Bonaventura ‡Nicola Vanacore Jinane Fattouch Anna Elisabetta Vaudano Gabriella Egeo †Alfredo Berardelli †Mario Manfredi Massimiliano Prencipe †Anna Teresa Giallonardo 《Epilepsia》2006,47(S5):64-67
Summary: Purpose: Psychogenic nonepileptic seizures (PNES) are episodes that may resemble epileptic seizures (ES) but are not associated with abnormal electrical discharges in the brain. Video-EEG recording of a typical episode is considered the best diagnostic tool available. PNES are, however, also documented in patients with epilepsy (PNES/ES). The purpose of this study was to assess this comorbid population, focusing on the differences between patients with PNES/ES and patients with PNES alone.
Methods: We reviewed 110 PNES episodes, occurring spontaneously or induced by means of suggestion techniques, recorded in our video-EEG laboratory over a period of eight years. We identified two subgroups of patients, consisting of 85 PNES cases and 25 PNES/ES cases, and assessed any differences in their characteristics by reviewing a number of variables (age, sex, clinical features, antiepileptic therapy, age of onset, time to diagnosis, pathological history, and length of follow-up).
Results: The comparison between the two subgroups revealed that PNES/ES patients displayed some statistically significant differences when compared with PNES alone patients, i.e., younger age, a higher percentage of spontaneously activated events, a shorter disease duration, a longer time to PNES diagnosis, and a lower percentage lost at follow-up.
Conclusions: This study confirms that PNES is a common, though probably underestimated, occurrence in epilepsy services. Our results shed light on some different characteristics between PNES and PNES/ES patients. 相似文献
Methods: We reviewed 110 PNES episodes, occurring spontaneously or induced by means of suggestion techniques, recorded in our video-EEG laboratory over a period of eight years. We identified two subgroups of patients, consisting of 85 PNES cases and 25 PNES/ES cases, and assessed any differences in their characteristics by reviewing a number of variables (age, sex, clinical features, antiepileptic therapy, age of onset, time to diagnosis, pathological history, and length of follow-up).
Results: The comparison between the two subgroups revealed that PNES/ES patients displayed some statistically significant differences when compared with PNES alone patients, i.e., younger age, a higher percentage of spontaneously activated events, a shorter disease duration, a longer time to PNES diagnosis, and a lower percentage lost at follow-up.
Conclusions: This study confirms that PNES is a common, though probably underestimated, occurrence in epilepsy services. Our results shed light on some different characteristics between PNES and PNES/ES patients. 相似文献
65.
The epidemiological survey of APH (3') I and APH (3') II genes, at a time when the specific antibiotic pressure was very low, was carried out by DNA-DNA hybridization. The sample included 334 aminoglycoside resistant Gram-negative bacteria collected from patients of a General Hospital. Of these, 251 hybridized with the APH (3') I-probe and 19 with the APH (3') II-probe but only 190 strains showed high resistance levels (CIM greater than 64 micrograms/ml) for kanamycin, neomycin and paromomycin. These strains were isolated both from inpatients and outpatients with different infectious diseases. The APH (3') I-gene was dispersed among all the bacterial species and clinical specimens tested but the APH (3') II-gene was not found in Pseudomonas spp, Escherichia coli, Citrobacter freundii and Enterobacter cloacae, nor in infected catheters. Several plasmids of different sizes carrying APH (3') genes were detected among different bacteria. Plasmids along with transposable elements (the probes used in this work were developed from Tn906 and Tn5) and the high consumption of other antibiotics whose resistance is carried by these bacteria might be playing an important role in the maintenance and dispersion of APH (3') genes. 相似文献
66.
67.
Lanzarini Luca Previtali Mario Bargiggia Giansiro Ferrario Maurizio Mussini Antonio Montemartini Carlo 《The international journal of cardiovascular imaging》1992,8(3):191-195
Aim of our study was to assess if the 2D-Echo transverse diameter of the left hepatic vein (LHV) obtained from the subcostal approach is correlated with invasive mean right atrial pressure (RAP). Thirty-two consecutive patients with acute myocardial infarction were studied by simultaneous 2D-Echo and right heart catheterization. LHV could be adequately imaged in 90% of patients. Mean RAP values at catheterization ranged from 0 to 15mmHg (mean 6±3.5 mmHg). A correlation was found between mean RAP and LHV diameter calculated after inspiration (r=0.81, SEE=1.54 mm, slope=0.71,p< 0.001) as well as after expiration (r=0.82, SEE=1.32mm, slope=0.62,p< 0.001) or during post-expiratory apnoea (r=0.85, SEE=1.3 mm, slope=0.71,p< 0.001). Moreover, percent increments of LHV diameter correlated well with percent changes of mean RAP during rapid infusion of 250–500 cc of saline in 4 patients (r=0.98,p< 0.001). Thus, the 2D-Echo LHV diameter is a feasible measurement that seems to correlate well with invasive mean RAP over a wide range of mean RAP values in patients with myocardial infarction; the changes in LHV diameter correlate well with the percent increase in central venous pressure obtained with saline infusion. Underestimation of invasive RAP occurs when mean RAP value exceeds 12 mmHg and can be explained by limited venous compliance. However these preliminary results suggest that this method may represent a valid alternative to obtain a non invasive estimate of mean RAP with 2D-Echocardiography. 相似文献
68.
C S Cleeland R K Portenoy M Rue T R Mendoza E Weller R Payne J Kirshner J N Atkins P A Johnson A Marcus 《Annals of oncology》2005,16(6):972-980
BACKGROUND: Cancer pain is highly prevalent and commonly undertreated. This study was designed to determine whether dissemination of a clinical protocol for pain management would improve outcomes in community oncology practices. PATIENTS AND METHODS: A pain management protocol was developed based on accepted guidelines. After baseline assessment, oncology practices were randomly assigned to 'analgesic protocol' (AP) sites, where oncologists implemented the guidelines in a group of lung or prostate cancer patients, or to 'physician discretion' (PD) sites, where customary treatment was continued. Patients treated on protocol and a comparison group of patients with pain due to breast cancer or myeloma were monitored for change in pain using the Brief Pain Inventory, and for change in other symptoms or mood. RESULTS: The protocol terminated early because of poor accrual. We compared groups using proportions of patients who had no or mild pain at follow-up. Although measures of protocol adherence did not suggest the occurrence of major practice change, the proportion of lung or prostate cancer patients with no or mild pain increased significantly from baseline for those treated at AP sites compared with those treated at PD sites. There was no significant difference between the breast and myeloma patients treated at AP sites versus those treated at PD sites. CONCLUSION: A protocol for cancer pain management can improve pain control. Diffusion of these benefits to other patients was not confirmed. Given the small sample size, these findings require confirmation in a larger trial. 相似文献
69.
70.
Maria G. Matera Mario Cazzola Maria Constantino Dante De Santis Francesco Rossi 《Clinical and experimental pharmacology & physiology》1992,19(9):627-630
1. Airways derived from different levels of the lung exhibit a difference in the reactivity and sensitivity to agonists. We have evaluated the effect of acetylcholine and cholinergic selective (pirenzepine, gallamine and 4-dipherylacetoxymethyl piperidine [4-DAMP]) and non-selective (atropine) antagonists on bovine proximal and distal smooth muscle preparations. 2. The distal preparations are more sensitive to acetylcholine than proximal bronchi. The relaxant effect of three selective antagonists on the distal and proximal tissues was the same when the results for each drug were compared. 3. Atropine and 4-DAMP were more potent than pirenzepine and gallamine in relaxing both proximal and distal bovine smooth muscle preparations. 4. These data suggest that the muscarinic sites on the smooth muscle of bovine airways are of the M3 subtype. 相似文献