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131.
Laura Palen Eichelberger 《American journal of public health》2010,100(6):1010-1018
132.
Dietary selenium (Se) status is inversely related to vulnerability to methylmercury (MeHg) toxicity. Mercury exposures that are uniformly neurotoxic and lethal among animals fed low dietary Se are far less serious among those with normal Se intakes and are without observable consequences in those fed Se-enriched diets. Although these effects have been known since 1967, they have only lately become well understood. Recent studies have shown that Se-enriched diets not only prevent MeHg toxicity, but can also rapidly reverse some of its most severe symptoms. It is now understood that MeHg is a highly specific, irreversible inhibitor of Se-dependent enzymes (selenoenzymes). Selenoenzymes are required to prevent and reverse oxidative damage throughout the body, particularly in the brain and neuroendocrine tissues. Inhibition of selenoenzyme activities in these vulnerable tissues appears to be the proximal cause of the pathological effects known to accompany MeHg toxicity. Because Hg's binding affinities for Se are up to a million times higher than for sulfur, its second-best binding partner, MeHg inexorably sequesters Se, directly impairing selenoenzyme activities and their synthesis. This may explain why studies of maternal populations exposed to foods that contain Hg in molar excess of Se, such as shark or pilot whale meats, have found adverse child outcomes, but studies of populations exposed to MeHg by eating Se-rich ocean fish observe improved child IQs instead of harm. However, since the Se contents of freshwater fish are dependent on local soil Se status, fish with high MeHg from regions with poor Se availability may be cause for concern. Further studies of these relationships are needed to assist regulatory agencies in protecting and improving child health. 相似文献
133.
Anna Gliszczyńska-Swig?o Hester van der Woude Laura de Haan Bozena Tyrakowska Jac M M J G Aarts Ivonne M C M Rietjens 《Toxicology in vitro》2003,17(4):423-431
The effects of quercetin on viability and proliferation of Chinese Hamster Ovary (CHO) cells and CHO cells overexpressing human quinone reductase (CHO+NQO1) were studied to investigate the involvement of the pro-oxidant quinone chemistry of quercetin. The toxicity of menadione was significantly reduced in CHO+NQO1 cells compared to wild-type CHO cells, validating the NQO1-overexpression in the CHO+NQO1 transfectant. Quercetin inhibited the proliferation of wild-type CHO and CHO+NQO1 cells to a similar extent without affecting cell viability, indicating that NQO1 enrichment of CHO cells did not provide increased protection. On the other hand, inhibition of NQO1 in both types of cells by dicoumarol significantly potentiated the inhibitory effect of quercetin on cell proliferation, revealing the role of NQO1 in cellular protection against quercetin. Altogether, these results can be explained by the hypothesis that both wild-type CHO and CHO+NQO1 cells contain sufficient NQO1 activity for optimal protection against the pro-oxidant effect of quercetin on cell proliferation. The results also point at a cellular NQO1 threshold for optimal protection against quercetin. This NQO1 threshold seems to be in the range of NQO1 activities already present in various tissues. 相似文献
134.
Bonnie L. Westra R.N. Ph.D. Laura Cullen R.N. M.A. Donna Brody R.N. M.S.N. Patricia Jump R.N. M.S. Letitia Geanon R.N. M.S. Ellen Milad R.N. M.S. 《Public health nursing (Boston, Mass.)》1995,12(6):393-399
Abstract Client (patient) satisfaction has been studied extensively in the health care sector, yet those receiving home health care services have been the focus of few studies. The purpose of this study was to test the reliability and validity of the Home Care Client Satisfaction Instrument (HCCSI). A total of 400 clients, randomly selected from 20 randomly chosen home care agencies in one state, completed the HCCSI and demographic form. Most respondents were older adults with multiple health problems and their families or informal support systems. Since data were skewed, item analysis was used. The revised instrument (HCCSI-R) is unidimensional and includes 12 items rated on a 5-point Likert scale measuring specific aspects of care. In addition, there are three global measures of satisfaction rated on a 10-point scale. All items except one had significant item-total correlations greater than .59. The total score correlates with likeliness to recommend the agency to others (.37, p = .0001), showing some evidence for criterion-related validity. 相似文献
135.
Daniel G. Remick Laura E. Deforge James F. Sullivan Henry J. Showell 《Immunological investigations》1992,21(4):321-327
The synovial fluid aspirated from patients with symptomatic arthritis was analyzed for the presence of tumor necrosis factor (TNF), interleukin 6 (IL-6) and interleukin 8 (IL-8). All three cytokines were found in both inflammatory and non-inflammatory arthritides: IL-8 levels ranged from less than 20 to 38,990 pg/ml, IL-6 from less than 10 to 72,300 pg/ml and TNF from less than 4 to 61 pg/ml. No inhibitors of cytokine activity were found. IL-8 and IL-6 were present in significantly higher levels in patients with inflammatory arthritis compared to patients with osteoarthritis, and there was significant correlation between the IL-6 and IL-8 levels. These findings document the presence of multiple cytokines in the synovial fluid specimens of patients with arthritis, and demonstrate that higher cytokine levels accompany inflammatory arthritis. 相似文献
136.
A comparison of the prevalence of rheumatoid arthritis and other rheumatic diseases amongst Pakistanis living in England and Pakistan 总被引:3,自引:0,他引:3
The impact of environmental factors on the causation of rheumatoid
arthritis (RA) is thought to be considerable. We explored this by comparing
the prevalence of RA amongst Pakistanis living in England, where it is
relatively high amongst ethnic English, and in Pakistan. The frequency of
other rheumatic diseases was also compared. Information on 2056 adult
Pakistanis in England and 4232 in Pakistan was obtained by house-to-house
surveys using identical protocols. Positive respondents were examined by
the same two clinicians in both countries. Rheumatic complaints increased
with age and were more common in females in both communities. The
standardized morbidity ratio (SMR) (95% CI) of RA in England was 2.1
(1.1-3.1) compared with Pakistan, a difference that was entirely
attributable to females. The SMR (95% CI) for women was 3.0 (0.4-5.6) and
for men 0.86 (-0.84 to 2.56). In Pakistan, there was a trend to more
reporting of some but not all rheumatic complaints amongst the affluent
segment of the population. This was increasingly apparent amongst those
resident in England and the possibility of an impact of easier
ascertainment amongst the more educated cannot be discounted. Low back pain
was significantly more common in England. Furthermore, the colder climate
was frequently invoked as a cause of more symptoms in England. Thus,
several factors may have influenced the observation that RA is more common
amongst Pakistanis in England compared with Pakistan. An environmental
factor cannot be excluded. However, the frequency of non-specific
musculoskeletal pain was similar. The regions of Pakistan from which the
two populations were derived were also different and immunogenetic
heterogeneity might also have contributed to the difference in RA
prevalence.
相似文献
137.
Aaron J Copeland Laura C Decoster Erik E Swartz Eric R Gattie Stephanie D Gale 《Clinical journal of sport medicine》2007,17(6):452-457
OBJECTIVE: To compare effectiveness of two techniques for removing football face masks: cutting loop straps [cutting tool: FMXtractor (FMX)] or removing screws with a cordless screwdriver and using the FMXtractor as needed for failed removals [combined tool (CT)]. Null hypotheses: no differences in face mask removal success, removal time or difficulty between techniques or helmet characteristics. DESIGN: Retrospective, cross-sectional. SETTING: NOCSAE-certified helmet reconditioning plants. PARTICIPANTS: 600 used high school helmets. INTERVENTIONS: Face mask removal attempted with two techniques. MAIN OUTCOME MEASUREMENTS: Success, removal time, rating of perceived exertion (RPE). RESULTS: Both techniques were effective [CT 100% (300/300); FMX 99.4% (298/300)]. Use of the backup FMXtractor in CT trials was required in 19% of trials. There was significantly (P<0.001) less call for the backup tool in helmets with silver screws (6%) than in helmets with other screws (31%). Mean removal time was 44.51+/-18.79s (CT: 37.84+/-15.37s, FMX: 51.21+/-19.54s; P<0.001). RPE was different between techniques (CT: 1.83+/-1.20, FMX: 3.11+/-1.27; P<0.001). Removal from helmets with silver screws was faster (Silver=33.38+/-11.03, Others=42.18+/-17.64; P<0.001) and easier (Silver=1.42+/-0.89, Other=2.23+/-1.33; P<0.001). CONCLUSIONS: CT was faster and easier than FMX. Most CT trials were completed with the screwdriver alone; helmets with silver screws had 94% screwdriver success. Clinically, these findings are important because this and other research shows that compared to removal with cutting tools, screwdriver removal decreases time, difficulty and helmet movement (reducing potential for iatrogenic injury). The combined-tool approach captures benefits of the screwdriver while offering a contingency for screw removal failure. Teams should use degradation-resistant screws. CLINICAL RELEVANCE: Sports medicine professionals must be prepared with appropriate tools and techniques to efficiently remove the face mask from an injured football player's helmet. 相似文献
138.
Francesco Franceschi Umile Giuseppe Longo Laura Ruzzini Paolo Simoni Bruno Beomonte Zobel Vincenzo Denaro 《Knee surgery, sports traumatology, arthroscopy》2007,15(3):266-268
Bilateral discoid medial menisci is an extremely rare condition of the knee and it can be associated to other pathological
findings, including anterior portion cyst formation. We report on the clinical features, radiographic findings, treatment
and results of one patient who presented a bilateral medial discoid meniscus combined with posterior portion cyst of the left
knee. To the best of the author’s knowledge, this is the first case of bilateral medial discoid meniscus associated with posterior
portion cyst formation. 相似文献
139.
T H Richardson J B Schenkman R Turcan P S Goldfarb G G Gibson 《Xenobiotica; the fate of foreign compounds in biological systems》1992,22(6):621-631
1. A polyclonal, monospecific antibody to a constitutive, diabetes-inducible and insulin-reversible cytochrome P-450 isozyme (RLM6) was used to screen a male rat liver cDNA library in lambda gt 11. Six clones harbouring the RLM6 cDNA insert were isolated initially from the expression library and three of these were further plaque-purified and sub-cloned. A 1.1 Kb cDNA insert, representing approximately 65% of the expected full length cDNA was characterized by restriction endonuclease mapping and sequenced by the dideoxy chain-termination method. Comparison of the nucleotide sequence of RLM6 cDNA to that of ethanol-inducible P4502E1 rat cDNA showed the two cDNAs to be identical, the RLM6 cDNA corresponding to nucleotides 310-1402 of the P4502E1 sequence. 2. RLM6 cDNA probe was used in Northern blot and RNA dot blot hybridization analysis to demonstrate that both streptozotocin-induced diabetes and fasting significantly elevated the steady-state level of RLM6 mRNA in male rat liver. Increased RLM6 mRNA level in the diabetic rat resulted in increased RLM6 apoprotein synthesis when polysomal RNA was used in a cell-free, protein-synthesizing system, indicating that the elevated RLM6 level observed in diabetic rats was correlated directly with the increased RLM6 mRNA concentration. 3. Daily insulin treatment of diabetic rats reversed the diabetes-dependent increase in RLM6 mRNA in a time-dependent manner, returning to control values after approximately 2 weeks of continuous insulin treatment. This insulin-dependent decrease of the RLM6 mRNA level was paralleled by a similar time-dependent decrease in serum acetone concentration. 4. Treatment of the male diabetic rat with testosterone also resulted in a decrease in both RLM6 mRNA and in vitro translated apoprotein. 5. Modulation of RLM6 mRNA level in the diabetic rat by insulin and testosterone, and the nucleotide sequence similarity with that of P4502E1 confirms that diabetes-inducible P450RLM6 and ethanol-inducible P4502E1 are coded for by the same gene. 相似文献
140.
K P Cantor A Blair G Everett S VanLier L Burmeister F R Dick R W Gibson L Schuman 《American journal of public health》1988,78(5):570-571
Data from a population-based case-control study of incident leukemia and non-Hodgkin's lymphoma among adult men in Iowa and Minnesota were used to evaluate risk associated with hair dye use. The relative risk for ever using hair dyes was 1.8 (95% confidence interval [CI] = 1.1-2.7) among leukemia patients, and 2.0 (CI = 1.3-3.0) among cases with non-Hodgkin's lymphoma. There was a suggestion of increased risk with extent of hair dye use. Given the widespread use of hair coloring products, these observations deserve more detailed evaluation in populations where the exposure is relatively common. 相似文献