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71.
The nephrotoxic mycotoxin ochratoxin A (OTA), a common contaminant of cereals, has been implicated in the etiology of endemic nephropathy. It was also frequently found in low concentrations in blood of healthy populations in countries where endemic nephropathy is not known. However, data on regional and seasonal differences in the frequency and concentration of OTA in human blood are scarce. In June, September and December 1997, and March 1998, about 50 human blood samples were collected randomly from blood donors for blood banks in the Coatian cities of Osijek, Rijeka, Split, VaraZdin and Zagreb. OTA was measured in the total of 983 samples using an HPLC technique with fluorescent detection. The daily intake of OTA was estimated from the mean concentration found in different cities and at different times of year. Samples containing OTA above the detection limit (0.2 ng/ml of plasma) were found in populations from all Croatian cities at all collecting periods. The highest frequency (59%) of samples containing OTA above the detection limit and the highest mean concentration (0.39 ng/ml) were found in June. Both the frequency and the mean concentration were lowest in all samples in December (36% and 0.19 ng OTA/ml, respectively). Osijek was the city with the highest frequency of OTA-positive samples (81%) and the highest mean OTA concentration (0.56 ng/ml). The total mean concentration of OTA in blood of healthy population in Croatia is lower (0.30 ng/ ml) than the mean concentration in European countries as a whole (0.90 ng/ml). The estimated daily intake, calculated from the mean concentration in all blood samples, is 0.40 ng OTA/kg body weight, which is much lower than that proposed by World Health Organization as the tolerable daily intake (16.0 ng/kg body weight). Healthy populations of Croatia are exposed to low, but seasonally and regionally variable amounts of OTA.  相似文献   
72.
ABSTRACT

Purpose

To evaluate quality of life in patients with uveitis-related to toxoplasmosis and its correlation with demographic, ocular involvement and psychosocial aspects.Methods: Data were collected through standardized interviews using a form to collect clinical and demographic data, in addition forms such as HADS, SF-12, NEI-VFQ-25 for health-related quality of life and anxiety and depression symptoms.Results: 81 patients were included with a mean age of 41.5 ± 14.5 years, females (50.6%) They were divided into three categories of best corrected visual acuity in the better seeing eye: normal (0-0.4 logMAR, 60 participants), low vision (0.48-0.9 logMAR, 9 participants) and blindness (>1 logMAR, 12 participants). The mean of VFQ-25 score was 75.5 ± 19.5 and the mean of SF-12 physical and mental components scores were 48.5 ± 7.4 and 52.4 ± 10.6 for health-related quality of life (HRQol). Anxiety symptoms were most prevalente than depression and were found in 38% of the subjects.Conclusions: Slightly more than a quarter of the sample presented impaired vision. It is associated with worsening of the quality of life since it affects mostly mental and related to the vision domains. This affects familiar, social and in addition, labor relations, since the majority of the subjects are in the economically active age group.  相似文献   
73.
Models have been developed for the analysis of dynamic contrast-enhanced MRI (DCE-MRI) data that do not require direct measurements of the arterial input function; such methods are referred to as reference region models. These models typically return estimates of the volume transfer constant (K(trans)) and the extravascular extracellular volume fraction (v(e)). To date such models have assumed a linear relationship between the measured R(1) ( identical with 1/T(1)) and the concentration of contrast agent, a transformation referred to as the fast exchange limit, but this assumption is not valid for all concentrations of an agent. A theory for DCE-MRI reference region models which accounts for water exchange is presented, evaluated in simulations, and applied in tumor-bearing mice. Using reasonable parameter values, simulations show that the assumption of fast exchange can underestimate K(trans) and v(e) by up to 82% and 46%, respectively. By analyzing a large region of interest and a single voxel the new model can return parameters within approximately +/-10% and +/-25%, respectively, of their true values. Analysis of experimental data shows that the new approach returns K(trans) and v(e) values that are up to 90% and 73%, respectively, greater than conventional fast exchange analyses.  相似文献   
74.
OBJECTIVE: Studies that investigated possible correlations between flexibility and muscular performance are scarce in the literature. Therefore, the purpose of this study was to investigate the impact of a program of static stretching on the flexibility of the hamstrings and on muscular performance of the knee flexors and extensors. DESIGN: Pre-post experimental design. SETTING: University laboratory. PARTICIPANTS: Thirty subjects aged 22.8 +/- 4.9 years with bilaterally shortened hamstrings. INTERVENTION: Using a protocol that has been previously described, the intervention consisted of 30 sessions of static stretching, performed bilaterally five times a week for 6 weeks. MAIN OUTCOME MEASUREMENTS: Measures of knee range of motion and isokinetic muscular performance (peak torque, angle of peak torque, and work) of knee flexors and extensors at speeds of 60 and 300 degrees/s. RESULTS: After intervention, significant gains in measures of flexibility (P < 0.0001) were observed, with an average gain of the knee-extension angle of 12.6 degrees, ranging from -1.2 to 30.7 degrees. In addition, we found significant increases in the following parameters of muscular performance: angle of peak torque of hamstrings at 60 and 300 degrees/s (P < 0.0001 and 0.018) and for work at 60 and 300 degrees/s for knee flexors (P = 0.012 and 0.005) and for knee extensors (P < 0.0001). CONCLUSIONS: The intervention resulted in gains in measures of flexibility, and these gains had a positive impact on some parameters of muscular performance.  相似文献   
75.

Background  

Vancomycin use is considered inappropriate in most hospitals. A particular concern is the recent emergence of S. aureus with decreased susceptibility to vancomycin, making it important to reduce overall exposure to vancomycin to minimize the incidence of VRE (vancomycin-resistant enterococci). The aim of this work was to analyze the use of vancomycin and the risk factors associated with inappropriate treatment.  相似文献   
76.
77.
Clinical treatment with the antineoplastic drug irinotecan (IRI) is often hindered by side effects that significantly reduce the quality of life of treated patients. Due to the growing public support for products with Δ9-tetrahydrocannabinol (THC), even though relevant scientific literature does not provide clear evidence of their high antitumour potential, some cancer patients take unregistered preparations containing up to 80 % THC. This study was conducted on a syngeneic colorectal cancer mouse model to test the efficiency and safety of concomitant treatment with IRI and THC. Male BALB/c mice subcutaneously injected with CT26 cells were receiving 60 mg/kg of IRI intraperitoneally on day 1 and 5 of treatment and/or 7 mg/kg of THC by gavage a day for 7 days. Treatment responses were evaluated based on changes in body, brain, and liver weight, tumour growth, blood cholinesterase activity, and oxidative stress parameters. Irinotecan’s systemic toxicity was evidenced by weight loss and high oxidative stress. The important finding of this study is that combining THC with IRI diminishes IRI efficiency in inhibiting tumour growth. However, further studies, focused on more subtle molecular methods in tumour tissue and analytical analysis of IRI and THC distribution in tumour-bearing mice, are needed to prove our observations.KEY WORDS: antitumour activity, cannabinoid-based preparations, oxidative stress, systemic toxicity  相似文献   
78.
Skeletal morphology is important in evolutionary, genetic, developmental, physiological, and functional studies. Although samples from free-ranging individuals may be preferable, constraints of sample size, demography, or conservation status may necessitate the inclusion of captive-born individuals. Captivity may be associated with physical, physiological, or behavioral differences that may affect skeletal form. This study assesses differences in postcranial skeletal form between free-range and captive-born Macaca mulatta and Saguinus oedipus. Samples included free-range M. mulatta from Cayo Santiago (Caribbean Primate Research Center) and captive-born macaques from the Wisconsin National Primate Research Center. S. oedipus samples included free-range born and captive-born individuals from the Oak Ridge Associated Universities Marmoset Research Center. Twenty-four dimensions of various bones, including the scapula, upper limb, innominate and lower limb, were recorded for adults. Age of epiphyseal closure was recorded for immature captive-born M. mulatta. Analysis of variance and principal component analyses tested significant differences between free-range born and captive-born individuals in each species. Significant differences were present in size and shape of postcrania between free-range and captive-born within taxa. Free-range macaques were larger than captive-born macaques, but this pattern did not consistently carry over to the Saguinus samples. Shape differences, while present throughout the skeleton, were especially prominent in the scapula. Differences in developmental timing, nutrition, and physical activity can be expected to contribute to the observed differences in postcranial skeletal form. These differences should be considered when captive-born primates are included in morphological or evolutionary studies. Anat Rec, 2018. © 2018 Wiley Periodicals, Inc. Anat Rec, 302:761–774, 2019. © 2018 Wiley Periodicals, Inc.  相似文献   
79.
Long-Term Epilation with Long-Pulsed Neodimium:YAG Laser   总被引:4,自引:0,他引:4  
BACKGROUND: Unwanted body hair can represent a severe cosmetic disturbance. The traditional methods used to epilate often have limitations, side effects, and unsatisfactory results. In recent years, various light sources (lasers and others) have been developed for long-term epilation of unwanted hair. OBJECTIVE: This study evaluates, on a large number of patients, the efficiency and safety of a long-pulsed low-potency Nd-Yag laser invented specifically for long-term hair removal. METHODS: Some 208 subjects needing epilation were divided into three groups and treated during an 11-month period. Group A included 79 patients with a normal distribution of unwanted hair; Group B 67 patients with constitutional hypertrichosis; and Group C 62 patients with hirsutism. Treatment sessions were performed with a fluence of 23-56 J/cm2 at 1-month intervals until obtaining desirable results. Follow-ups ranged from 1 to 6 months. In 3 patients 4-mm diameter punch biopsy specimens were obtained before the first session and again after 6 hours. A third biopsy was performed after 3 months. RESULTS: Every session resulted in a 20-40% hair loss, depending on the color of hair. Complete epilation was obtained in 4 to 6 sessions. Only white hair was not receptive to laser light, and its growth was not modified. No patients, including dark-complexioned patients, had blistering, hypo-or hyperpigmentation. No pain was present during treatment except for the axillary area. In the specimen obtained after 6 hours, very extensive necrosis of the hair follicular and sebaceous gland epithelium was evident. Histologic findings of the biopsies taken after three months showed complete disappearance of hair and moderate fibrosis. CONCLUSION: This study proves that the long-pulsed Nd:Yag laser treatment produces an excellent prolonged epilation with no relevant side effects. This laser light, having a 1064 nm wavelength, is minimally absorbed in superficial skin layers, and pronounced scattering up to 5 mm occurs targeting the deeper follicles.  相似文献   
80.
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