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51.
52.
The aim of this research is to find out whether the firefighter manpower is adequate to the requirements in the field under the most severe conditions. It also attempts to test whether firefighters' working ability corresponds to their age. To that purpose 220 Croatian firefighters from the Littoral Mountainous county, 99 professional firefighters from the city of Rijeka, 45 professional firefighters from its suburbs and 76 volunteer firefighters from the suburbs were submitted to load test, fitness test--stepping on the bench for three minutes, repetitive power test--sit-ups lasting 1 minute, and a leap-explosive power test. The fitness test was repeated carrying Drd?er's respiratory apparatus PSS 100 with compressed air, so respiratory values were compared before and after the burden of the respiratory apparatus. The results have shown that professional firefighters from the city have the mean increased body mass index (BMI) 26, and professionals from the suburbs BMI 27. In spite of the increased body mass they showed good fitness, spirometric values before and after the load showed neither restrictive nor obstructive ventilation difficulties, which indicates a good condition of cardio respiratory system and also adequate protective equipment. The initial hypothesis has been confirmed: with age, equipped with personnel does not necessarily mean operative equipment, because linear regressive analyses have shown a negative correlation coefficient in relation to repetitive and explosive power. Also, on the average somewhat younger volunteer firefighters are stronger in performing the repetitive power test (p < 0.05) compared to professional firefighters. Occupational medicine should suggest administrative health measures to improve the accelerated retirement plan and shorten the shifts so that all available firefighters could instantaneously be included in the field intervention.  相似文献   
53.
Pulmonary embolism caused by a foreign body is an exceedingly rare event. We report on a 62 year old woman who suffered a gun shot injury to her left knee with concomitant vascular lacerations. The bullet migrated through the venous system into the pulmonary circulation causing a pulmonary embolism. The projectile remained stationary for ten years. Taking into consideration that she is virtually asymptomatic and that regular follow up examinations showed no further migration of the foreign body, we opted for a conservative venue of management.  相似文献   
54.
Chronic diseases cause high frequency visits and generate the long-term frequent attenders (FAs). The connection between frequent attendance and specific morbidities in the health care systems in transitional Europe has been underestimated. We investigated whether frequent visits of chronic patients in primary care are related to characteristic of chronic disease (diabetes mellitus) and whether this is influenced by the family practice in the transitional health care. We analyzed the number of visits a day time work for 490 persons with diabetes in the period 1997 to 2000. As the cut-off points between frequent attenders and non frequent attenders (NFAs) we used the value of the third quartile (Q3) of visits determined for the sex and age groups in the parallel study in the whole population. The analysis was performed for 23 variables: demographic characteristics of patients, disease characteristic and variables of physician. Logistic regressions were employed to identify the predictors of FAs/NFAs. 56.9% (in 1997) to 62.4% (in 2000) persons with diabetes were FAs, compared to 22.4% to 24.3% FAs patients in the whole population. Logistic regression analysis significantly differentiated the two group of visits with 68% accuracy. 4 variables are significant predictors for FAs/NFAs: diabetes as the main disease (p = 0.0005), diet-only-treatment (p = 0.0062), treatment by secondary care (p = 0.0116), and if glycated hemoglobin test (HbA1c) is determined (p = 0.0272). Understanding the similarities and differences of FAs/NFAs persons with diabetes may be important in improving the care and management of chronic diseases in family medicine in transitional health care systems.  相似文献   
55.
The total of 178 firefighters from the Littoral Mountainous County, the Republic of Croatia, have undergone psychotestings in three groups--99 professionals from city Rijeka, 44 professionals from suburb and 35 volunteers from suburb. The scores of PSS 10 Cohen Stress Perception Scale, COPE questionnaire, STAI X1 anxiety test as condition and STAI X2 anxiety test as trait personality and Beck Depression Inventory were analyzed. The results have shown that firefighters do not suffer from negative effects of stress. There is slight anxiety as condition in city firefighters and medium anxiety as trait personality in all firemen. All firefighters are often problem-oriented, need only occasionally compassion of environment and sometimes react by avoiding to face stress. They differ significantly by depression (p < 0.001), which is negligible in relation to ordinary population. "Working anxiety", i.e. medium anxiety which is a distinctive trait of their personality becomes the necessary initiator of functioning in the most difficult working conditions.  相似文献   
56.
Phosphatidylinositol-specific phospholipase C (PI-PLC) is activated in cell nuclei during the cell cycle progression. We have previously demonstrated two peaks of an increase in the nuclear PI-PLC activities in nocodazole-synchronized HL-60 cells. In this study, the activity of nuclear PI-PLC was investigated in serum-stimulated HL-60 cells. In serum-starved HL-60 cells, two peaks of the activity of nuclear PI-PLC were detected at 30 min and 11 h after the re-addition of serum with no parallel increase in PLC activity in cytosol, postnuclear membranes or total cell lysates. An increase in the serine phosphorylation of b splicing variant of PI-PLCbeta(1) was detected with no change in the amount of PI-PLCbeta(1b) in nuclei isolated at 30 min and 11 h after the addition of serum. PI-PLC inhibitor ET-18-OCH(3) and MEK inhibitor PD 98059 completely abolished serum-mediated increase at both time-points. The addition of inhibitors either immediately or 6 h after the addition of serum had inhibitory effects on the number of cells entering S phase. These results demonstrate that two waves of nuclear PI-PLCbeta(1b) activity occur in serum-stimulated cells during G(1) phase of the cell cycle and that the later increase in the PLC activity is equally important for the progression into the S phase.  相似文献   
57.
BACKGROUND: Early clinical trials for gene therapy of human gliomas with retroviral packaging cells (PC) have been hampered by low transduction efficacy and lack of dissemination of PC within the tumor. In the current approach, these issues have been addressed by creating a stable packaging cell line for retroviral vectors pseudotyped with glycoproteins of lymphocytic choriomeningitis virus (LCMV) based on tumor-infiltrating progenitor cells. METHODS: Tumor-infiltrating progenitor cells, which had been isolated from adult rat bone marrow (BM-TIC), were modified to stably express Gag-Pol proteins of moloney murine leukemia virus (Mo-MLV) and glycoproteins of LCMV. Packaging of a retroviral vector was measured by titration experiments on human fibroblast cells as well as on mouse and human glioma cell lines. Additionally, gene transfer was tested in a rat glioma model in vivo. RESULTS: The BM-TIC-derived packaging cell line (BM-TIPC) produced retroviral vectors with titers between 2-8 x 10(3) transducing units (TU)/ml. Extended culturing of BM-TIPC over several weeks and freezing/thawing of cells did not affect vector titers. No replication-competent retrovirus was released from BM-TIPC. In a rat glioma model, BM-TIPC infiltrated the tumors extensively and with high specificity. Moreover, BM-TIPC mediated transduction of glioma cells in vivo. CONCLUSION: This proof-of-principle study shows that primary adult progenitor cells with tumor-infiltrating capacity can be genetically modified to stably produce retroviral LCMV pseudotype vectors. These BM-TIPC may be a useful tool to enhance specificity and efficacy of gene transfer to gliomas in patients.  相似文献   
58.
In 80 adult patients with community acquired pneumonia (CAP) conventional microbiological methods, polymerase chain reaction (PCR) and serum C-reactive protein (CRP) levels were performed and the appropriateness of the empirical antimicrobial treatment was evaluated according to bacterial pathogen detected. The aetiology was determined in 42 (52.5%) patients, with Streptococcus pneumoniae as the most common pathogen. PCR applied to bronchoalveolar lavage (BAL) provided 2 and PCR on sputum samples 1 additional aetiological diagnosis of CAP The mean CRP values in the S. pneumoniae group were not significantly higher than in the group with other aetiological diagnoses (166.89 mg/L vs. 160.11 mg/L, p = 0.457). In 23.8% (10/42) of patients with determined aetiology, the empirical antimicrobial treatment was inappropriate. PCR tests need further investigation, particularly those for the atypical pathogens, as they are predominant in inappropriately treated patients. Our results do not support the use of CRP as a rapid test to guide the antimicrobial treatment in patients with CAP.  相似文献   
59.
This study examined individual and combined influence of smoking, physical inactivity, alcohol drinking, and unhealthy diet on total mortality. Relationship between individual and combined poor health behaviours and total mortality were examined using Cox proportional hazards regression. Out of 7490 individuals included in the study, during 5 years follow up 808 died. Adjusted hazard ratios (HRs), and 95% confidence intervals (95% CIs) for men with health behaviour scores 1, 2, 3, and 4 compared with those with score 0 were 1.67 (1.24-2.24), 2.28 (1.64-3.18), 2.24 (1.32-3.84), and 2.86 (0.77-11.70), respectively (p value for trend < 0.001). Adjusted HRs (95% CIs) for women with health behaviour scores 1, 2, and 3 compared with those with score 0 were 1.17 (0.97-1.42), 1.37 (1.02-1.86), and 1.20 (0.37-3.61), respectively (p value for trend = 0.04). A unit of the health behaviour score increased mortality risk equivalent to being 5.9 and 2.9 years older, for man and woman respectively.  相似文献   
60.
Tissue disintegration after injury leads, in the endoplasmic reticulum (ER), to activation of adaptive pathways known as the ER stress response. It is directed to the correction of unfolded proteins and to the activation of proteasome-dependent ER-associated degradation of the misfolded proteins, but induces also a rapid activation of natural and adaptive immunity, since a ER resident heat shock protein-gp96 acts not only as a molecular chaperone, but also as a strong adjuvant, able to cross-present the antigenic peptides onto MHC class I or MHC class II pathways. Analyzing its potential role in processes of normal growth, in mice subjected to 1/3 partial hepatectomy (pHx) we determined the tissue expression of gp96 protein and mRNA in regenerating liver, thymus and spleen, determining simultaneously the phenotypic profile and spontaneous cytotoxic activity of intrahepatic and splenic mononuclear lymphatic cells (MNLC) against NKT- and NK-cells sensitive targets (syngeneic thymocytes and YAC-1) in wild, perforin and FasL deficient mice. The data have shown that pHx induces fast overexpression of gp96 protein and mRNA in hepatocytes, spleen and thymus, with accumulation of CD3intermediate/NK1.1+/CD69+ cells (liver) and Foxp3+CD4+CD25+ cells (liver and thymus). Simultaneously, intrahepatic MNLC acquired the FasL-dependent cytotoxic potential against NKT-sensitive targets and both, intrahepatic and splenic MNLC, acquired the perforin-dependent cytotoxic potential against NK-sensitive targets, implying that during the disturbance of morphostasis gp96 serves as a natural adjuvant for chaperoning antigenic self peptides into the immune surveillance pathways, resulting in activation of autoreactive NKT and regulatory cells, as well as NK cells. Moreover, cell cycle analysis revealed that G2+M phase of regenerating hepatocytes in PKO mice was translocated from the 1st to the 7th p. o. day, as well as that hepatocytes from FasL deficient mice were arrested in G0/G1 phase.  相似文献   
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