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61.
Jean -Marc Bollag Marek Duszota 《Archives of environmental contamination and toxicology》1984,13(3):265-270
Live and dead cells of several strains of bacteria as well as different microbial populations isolated from natural environments were tested for their ability to sorb cadmium (Cd) from a liquid medium (0.05M phosphate buffer, pH 7.2) containing 10 g Cd/ml. The bacterial cultures were grown in a nutrient solution without Cd, harvested, and then suspended in the buffer solution for the uptake assays. The amount of Cd sorbed by dead cells was usually higher than by live cells. Killing of bacteria by chemicals (ethanol, formaldehyde, or propylene oxide) or physical (-radiation) means had a varying effect on Cd uptake by dead cells. Various bacterial strains showed different degrees of resistance to Cd and different uptake levels of this heavy metal with no established correlation. Neither storage of the cells at 4°C for 48 hr after harvesting nor varying incubation times of the bacteria before the Cd uptake experiments had any influence on the amount of Cd sorbed.Paper No. 6609 of the Journal Series of the Agricultural Experiment Station, Pennsylvania State University, University Park, PA 16802 相似文献
62.
PurposeLate-diagnosed dislocated hips underwent open reduction, Dega osteotomy, and proximal femoral osteotomy between 1968 and 1988. The objectives of this study are to assess the survival of hips into adulthood, clinical and radiological outcome, patients’ life perspectives and the risk factors of failure.MethodsAn assessment of 67 hips treated when younger than five years (<age 5yr. group) and 71 hips in the group aged older than five years (+age 5yr.) was performed. All cases were evaluated clinically and radiographically, and survival was assessed, considering hip replacement as endpoints for failure (abbreviation HR+ refers to hips that underwent hip replacement surgery; HR- refers to hips that have not been replaced at the follow-up). The fertility rate and the social security disability benefits (SSDB) recipiency percentage were calculated.ResultsThe 40-year survival rates were 73% (95% confidence (CI) 71% to 76%) in the <age 5yr. group, 54% (95% CI 51% to 57%) in the +age 5yr. group, 70% (95% CI 67% to 73%) in one-sided dislocations and 57% (95% CI 54% to 60%) in bilateral dislocations. At follow-up, the median Harris hip and Western Ontario and McMaster Universities Osteoarthritis scores were 90.0 and 13.0 (<age 5yr. group, HR-), 74.0 and 28.0 (+age 5yr. group, HR-), 90.0 and 16.0 (<age 5yr. group, HR+) and 84.5 and 11.5 (+age 5yr. group, HR+), respectively. The operation normalized the radiological parameters. The correlation between the grade of femoral head avascular necrosis (AVN) at a median 2.6 years after the operation and the grade of osteoarthritis at follow-up was 0.38 (p < 0.001). The fertility rate was 1.54. In total, 16.0% (aged under five years) and 38.5% (aged over five years) of patients were receiving SSDB (p = 0.003).ConclusionEarly failure risk factors are older age at the surgical procedure, high AVN grade and bilateral hip involvement. Still, the results facilitate hip reposition whenever technically manageable, even in teenagers.Level of evidenceIII 相似文献
63.
64.
Jana Jedlickova Marie Vajter Tomas Barta Graeme C. M. Black Rahat Perveen Jan Mares Marek Fichtl Bohdan Kousal Lubica Dudakova Petra Liskova 《Clinical genetics》2023,104(4):418-426
Four members of a three-generation Czech family with early-onset chorioretinal dystrophy were shown to be heterozygous carriers of the n.37C>T in MIR204. The identification of this previously reported pathogenic variant confirms the existence of a distinct clinical entity caused by a sequence change in MIR204. Chorioretinal dystrophy was variably associated with iris coloboma, congenital glaucoma, and premature cataracts extending the phenotypic range of the condition. In silico analysis of the n.37C>T variant revealed 713 novel targets. Additionally, four family members were shown to be affected by albinism resulting from biallelic pathogenic OCA2 variants. Haplotype analysis excluded relatedness with the original family reported to harbour the n.37C>T variant in MIR204. Identification of a second independent family confirms the existence of a distinct MIR204-associated clinical entity and suggests that the phenotype may also involve congenital glaucoma. 相似文献
65.
Acute effects of using a mobile phone on CNS functions 总被引:9,自引:0,他引:9
Hladký A Musil J Roth Z Urban P Blazková V 《Central European journal of public health》1999,7(4):165-167
Twenty volunteers participated in two experiments exploring the acute effects of using the mobile phone Motorola GSM 8700 on the functions of the CNS. When speaking (5 minutes reading a text from daily newspapers) the electromagnetic fields from the mobile apparatus did not affect the visual evoked potentials. Also a 6-min exposure did not reveal any effect of electromagnetic fields on the results in two tests (memory and attention) performed while speaking into the mobile. On the other hand the phone call itself strongly influenced the performance in a secondary task applying a test of switching attention which is a good model for driving a car. The response and decision speed were significantly worse. This is a proof that even a slight psychological stress involved in calling while driving can be a great risk. 相似文献
66.
Increased plasma tumour necrosis factor (TNF) concentration correlates with mortality in sepsis. We suggested that pentoxifylline (PTXF), which is known to inhibit TNF production, may improve survival and attenuate clinical symptoms of sepsis in neonates. Plasma TNF levels were evaluated in 29 newborn infants with sepsis. Patients were randomly assigned into two groups, receiving PTXF in a dose of 5 mg/kg per hour for 6 h or placebo (saline), on 3 successive days. Both groups were subjected to the same conventional therapy. TNF was evaluated before and after PTXF or placebo administration on the 1 st and 3rd days of therapy. There was a statistically significant decrease in plasma TNF level in the PTXF group when the values before the first and after the last PTXF infusion were compared [mean: 671.5 pg/ml; SD: 438; med: 729.6 vs mean: 41.0 pg/ml; SD: 64.1; med: 11.5;P<0.000004]. In the placebo group, decrease was not significant [mean: 633.0 pg/ml SD: 488.6; med: 618.9 vs 246.9 pg/ml; SD: 243.9; med: 191.0]. A significantly higher plasma TNF level, evaluated after the last PTXF infusion, was found in the placebo group [246,9 pg/ml vs 41.0 pg/ml;P<0.001]. Only one of four infants with signs of shock in the placebo group survived, whereas all of five newborns with symptoms of shock in the PTXF group survived [P<0.04]. An increased incidence of metabolic acidosis [P<0.05], necrotizing enterocolitis [P<0.04] and renal insufficiency [P<0.05] was observed in infants in the placebo group.Conclusion PTXF inhibits production of TNF and may have therapeutic value in the treatment of premature infants with sepsis complicatea by shock. 相似文献
67.
Ostrowska Z Swientochowska E Buntner B Marek B Zwirska-Korczala K Spyra Z Banas I 《Endocrine regulations》1996,30(2):83-92
In starved rats the mutual interrelations were studied between the secretion of melatonin (MEL), thyroid hormones (TT[_4], FT[_4], TT[_3], FT[_3], rT[_3]), corticosterone (B), testosterone (T) and some markers of collagen metabolism: serum concentrations of carboxyterminal propeptide of type I procollagen (PICP) and aminoterminal propeptide of type III procollagen (PIIINP) (determined by RIA method) as well as urine concentration of hydroxyproline (OH-Pr) (determined by colorimetric method). Starved rats were found to have significantly increased serum MEL, B, and rT[_3] concentrations while serum values of TT[_4], FT[_4], TT[_3], FT[_3], T and PICP as well as urinary OH-Pr were significantly decreased. The concentrations of PICP, PIIINP and OH-Pr correlated negatively with MEL and B values, but positively with TT[_4] and FT[_4]. It was concluded that starving may change the collagen metabolism in rats indirectly via a modulating effect of changes in MEL, thyroxine and corticosterone. 相似文献
68.
56 patients with bronchial asthma (32 women and 24 men) and 31 healthy volunteers (19 women and 12 men) were investigated. The evaluation of the usefulness of salivary and urinary cortisol levels and urinary cortisol metabolites in 24-hr urine was conducted using the correlation coefficient between the cortisol level in the salivary or urine and that in blood serum. Very high correlation was found between the serum and salivary cortisol level (r=0.817). The correlation coefficient between the serum and urinary cortisol level in basal conditions was 0.759, while that between the saliva and urinary level was 0.723. A moderate degree of correlation (r=0.381) was demonstrated between serum cortisol level and 17-OHCS in urine. From these results it was concluded that salivary and urinary free cortisol level estimations may be a useful and non-invasive screening method of evaluating the glucocorticoid function of the adrenal cortex in asthma patients. 相似文献
69.
Hennig Ewa E.; Demkowicz-Dobrzanski Krzysztof K.; Sawicki Jozef T.; Mojska Hanna; Kujawa Marek 《Carcinogenesis》1983,4(10):1243-1246
The effect of butylated hydroxyanisole (BHA) administrationon the hepatic monooxygenase system of nuclear and microsomalfraction was investigated in male mice. Addition of BHA to thediet significantly lowered the content of cytochrome P-450 inliver nuclei and increased the specific activity of NADPH-cytochromec reductase and the content of cytochrome b5 in liver microsomes.Incubation of benzo[a]pyrene (BP) with liver nuclei from BHA-fedmice resulted in inhibition of binding of BP metabolites tonuclear macromolecules by 50% compared with control. However,there was no effect of BHA on the binding of BP metabolitesto macromolecules when BP was incubated with added DNA and livermicrosomes from BHA-fed mice. It has been postulated that modificationof nuclear monooxygenases by BHA may play a role in the inhibitoryeffect of BHA on BP carcinogenesis. 相似文献
70.
Beata Gawdis-Wojnarska Marek Brzosko Jacek Fliciński Krzysztof Marlicz Teresa Starzyńska Rodney J Scott Jan Lubiński 《Hereditary cancer in clinical practice》2004,2(2):65-68
Gastric cancer is the second most frequently diagnosed malignancy worldwide and therefore represents a significant healthcare burden. Environmental and genetic factors are involved in the development of gastric cancer. To date only one clear genetic predisposition has been identified involving mutations in the E-cadherin gene. The disease phenotype in patients harbouring E-cadherin mutations appears to be specifically related to diffuse gastric cancer. Little is known genetically about the other forms of gastric cancer. Since there is a growing awareness about the necessity of early intervention criteria have been developed that aid the identification of hereditary forms of gastric cancer. The aim of the current study was to identify minimal inclusion criteria so that nuclear pedigree families can be provided with risk assessment and/or genetic testing.The results reveal that inclusion features described herein such as (a) gastric cancer diagnosed before 46 years of age; (b) two gastric cancers among first degree relatives diagnosed over the age of 50 are useful in identifying suspected hereditary gastric cancer patients. 相似文献