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1.
BMC Geriatr ; 20(1): 149, 2020 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-32321436

RESUMO

BACKGROUND: This study explored the effects of physical activity and sedentary behaviour on the decline of cognitive ability among the elderly. To compensate for the limitations of self-reported physical activity, objective measures were used. METHODS: A cross-sectional survey of 308 aged people mean 68.66 ± 5.377 years, in Nanjing, China, was conducted. Physical activity was measured using the ActiGraph GT3X+, and cognitive function was measured using the Montreal Cognitive Assessment. RESULTS: The overall participant model, adjusted for age, BMI, education, and monthly average income, found that light physical activity (ß = 0.006, p < 0.01), moderate-vigorous physical activity (ß = 0.068, p < 0.001), and total physical activity (ß = 0.006, p < 0.01) had a significant linear relationship with cognitive ability, while sedentary time did not (ß = - 0.020, p>0.05). Further, light physical activity only affects the cognitive ability of elderly females (ß = 0.006, p < 0.05). There was an inverted 'U' association between moderate-vigorous physical activity and cognitive ability. The association models found that moderate-vigorous physical activity in the 22.13 min·day- 1~38.79 min·day- 1 range affected cognitive ability most beneficially, with the highest beta coefficient among all groups (ß = 0.091, p < 0.05). CONCLUSIONS: While physical activity can significantly improve cognitive ability among the elderly, sedentary behaviour is associated with decreased cognitive function across genders.


Assuntos
Cognição , Exercício Físico , Comportamento Sedentário , Acelerometria , Idoso , China , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
2.
BMC Public Health ; 19(1): 1459, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31694592

RESUMO

BACKGROUND: Urbanization and aging are global phenomena that offer unique challenges in different countries. A supportive environment plays an important role in addressing the issues of health behavioral change and health promotion (e.g., prevent chronic illnesses, promote mental health) among older adults. With the development of the socio-ecological theoretical model, studies on the impact of supportive environments on physical activity have become popular in the public health field in the EU and US. Meanwhile, very few Chinese studies have examined the relationship between built environment features and older adults' physical activity at the ecological level. The purpose of the study is to investigate how the factors part of the built environment of Nanjing's communities also influence leisure time physical activity among the elderly. METHODS: Using a socio-ecological model as a theoretical framework, we conducted a cross-sectional study of 399 elderly people from 19 communities in Nanjing, China, using a one-on-one questionnaire to collect data, including participants' perceived built environment and self-reported physical activity. A multivariate linear regression method was used to analyze the factors influencing their recreational physical activity. RESULTS: This study found that compared to older people with low average monthly income, the recreational physical activity of the elderly with average monthly incomes between 1001 and 2000 ¥ (ß = 23.31, p < 0.001) and 2001 ¥ or more (ß = 21.15, p < 0.001) are significantly higher. After controlling for individual covariates, street connectivity (ß = 7.34, p = 0.030) and street pavement slope (ß = - 7.72, p = 0.020), we found that two out of ten built environment factors indicators influence their physical activity. The importance of each influencing factor ranked from highest to lowest are monthly average income, street pavement slope, and street connectivity. Other factors were not significantly related to recreational physical activity by the elderly. CONCLUSIONS: Older adults with a high income were more likely to participate in recreational physical activity than those with a low income. In order to positively impact physical activity in older adults and ultimately improve health, policymakers and urban planners need to ensure that street connectivity and street pavement slope are factored into the design and development of the urban environment.


Assuntos
Ambiente Construído , Exercício Físico/psicologia , Atividades de Lazer/psicologia , Apoio Social , Urbanização , Idoso , Idoso de 80 Anos ou mais , China , Estudos Transversais , Fenômenos Ecológicos e Ambientais , Pesquisa Empírica , Planejamento Ambiental , Feminino , Promoção da Saúde , Humanos , Renda , Masculino , Saúde Mental , Modelos Teóricos , Pobreza/psicologia , Análise de Regressão , Autorrelato
3.
Chemistry ; 23(66): 16862-16870, 2017 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-28906036

RESUMO

Electrocatalytic splitting of water is becoming increasingly crucial for renewable energy and device technologies. As one of the most important half-reactions for water splitting reactions, the oxygen evolution reaction (OER) is a kinetically sluggish process that will greatly affect the energy conversion efficiency. Therefore, exploring a highly efficient and durable catalyst to boost the OER is of great urgency. In this work, we develop a facile strategy for the synthesis of well-defined phosphorus and fluorine co-doped Ni1.5 Co1.5 N hybrid nanorods (HNs) by using ionic liquids (ILs; 1-butyl-3-methylimidazolium hexafluorophosphate). In comparison to the IrO2 catalyst, the as-obtained PF/Ni1.5 Co1.5 N HNs manifests a low overpotential of 280 mV at 10 mA cm-2 , Tafel slope of 66.1 mV dec-1 , and excellent durability in 1.0 m KOH solution. Furthermore, the iR-corrected electrochemical results indicate it could achieve a current density of 100 mA cm-2 at an overpotential of 350 mV. The combination of cobalt and nickel elements, 1D mesoporous nanostructure, heteroatom incorporation, and ionic liquid-assisted nitridation, which result in faster charge transfer capability and more active surface sites, can facilitate the release of oxygen bubbles from the catalyst surface. Our findings confirm that surface heteroatom doping in bimetallic nitrides could serve as a new class of OER catalyst with excellent catalytic activity.

4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(2): 509-12, 2017 Feb.
Artigo em Zh | MEDLINE | ID: mdl-30280551

RESUMO

A rapid UV-Vis spectrophotometric method was proposed to determine the concentration of DMP in aqueous solutions. The linear concentration range of DMP solution at the range of 250~400 nm is 0.5~70 mmol·L(-1). At 275 nm, the linear fitting equation is A=0.030 7c+0.133 0 with a correlation of 0.980 9. The detection limitation is 9.46×10-5 mmol·L-1, the RSD (n=6) of the method were at the range of 0.100%~0.612%. The recovery ratio for salt solutions sample is 95%~104%. Temperature, pH, and coexisting K(+), Na(+), Mg(2+), Cl(-), Br(-), I(-), SO(2-)(4) ions do not affect the detection. The coexisting CO(2-)(3) and HCO(-)(3) ions can be eliminated with acidification. The results showed that the proposed method is simple in pretreatment process and has high accuracy and precision. It is a quick measurement method of DMP concentration in water solution, and can be used to measure DMP concentration in reverse flotation tail liquid and reverse flotation material pulp.

5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(10): 2825-9, 2015 Oct.
Artigo em Zh | MEDLINE | ID: mdl-26904826

RESUMO

The high similarity of MO and EO made it difficult to measure concentration of MOD and EOD. In this paper, dual wavelength spectrophotometry was used to determinate the concentration of MOD and EOD, which was proved to be fast and accrate. 429.00 nm and 469.50 nm were selected as detemination wavelengthes at pH 12. And the influences of Na+ and Cl- on determination of MOD and EOD were surveyed. The standard equations were A429 = 0.003 47 + 0.061 cm + 0.056 46 C(E) and A469.50 = 0.002 8 + 0.074 37 cm + 0.083 94 c(E) . Recovery of standard additions of MOD and EOD were larger than 95%, and relative standard deviation of standard equations were less than 2%. The addition of NaCl has little effect on recovery of standard additions and relative standard deviation of this method.

6.
Angew Chem Int Ed Engl ; 54(36): 10530-4, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26218453

RESUMO

Identifying effective means to improve the electrochemical performance of oxygen-evolution catalysts represents a significant challenge in several emerging renewable energy technologies. Herein, we consider metal-nitrogen-carbon sheets which are commonly used for catalyzing the oxygen-reduction reaction (ORR), as the support to load NiO nanoparticles for the oxygen-evolution reaction (OER). FeNC sheets, as the advanced supports, synergistically promote the NiO nanocatalysts to exhibit superior performance in alkaline media, which is confirmed by experimental observations and density functional theory (DFT) calculations. Our findings show the advantages in considering the support effect for designing highly active, durable, and cost-effective OER electrocatalysts.

7.
Bioinorg Chem Appl ; 2024: 8843214, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38204734

RESUMO

Purpose: The crystal adhesion caused by the damage of renal tubular epithelial cells (HK-2) is the key to the formation of kidney stones. However, no effective preventive drug has been found. This study aims to explore the recovery effects of four Laminaria polysaccharides (SLPs) with different sulfate (-OSO3-) contents on damaged HK-2 cells and the difference in the adhesion of damaged cells to nanometer calcium oxalate monohydrate (COM) and calcium oxalate dihydrate (COD) before and after recovery. Methods: Sodium oxalate (2.6 mmol/L) was used to damage HK-2 cells to establish a damaged model. SLPs (LP0, SLP1, SLP2, and SLP3) with -OSO3- contents of 0.73%, 15.1%, 22.8%, and 31.3%, respectively, were used to restore the damaged cells, and the effects of SLPs on the adhesion of COM and COD, with a size of about 100 nm before and after recovery, were measured. Results: The following results were observed after SLPs recovered the damaged HK-2 cells: increased cell viability, restored cell morphology, decreased reactive oxygen levels, increased mitochondrial membrane potential, decreased phosphatidylserine eversion ratio, increased cell migration ability, reduced expression of annexin A1, transmembrane protein, and heat shock protein 90 on the cell surface, and reduced adhesion amount of cells to COM and COD. Under the same conditions, the adhesion ability of cells to COD crystals was weaker than that to COM crystals. Conclusions: As the sulfate content in SLPs increases, the ability of SLPs to recover damaged HK-2 cells and inhibit crystal adhesion increases. SLP3 with high -OSO3- content may be a potential drug to prevent kidney stones.

8.
Inorg Chem ; 51(11): 6081-8, 2012 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-22587710

RESUMO

A new series of polynuclear superalkali cations YLi(3)(+) (Y = CO(3), SO(3), SO(4), O(4), and O(5)) has been created when the central group is surrounded by alkali atoms. The structural characteristics and stabilities of these systems are provided on the basis of ab initio methods. In the lowest-energy structure of the CO(3)Li(3)(+), SO(3)Li(3)(+), and SO(4)Li(3)(+) cations, the central Y (Y = CO(3), SO(3), and SO(4)) group features a slight distortion. The global minima of O(4)Li(3)(+) and O(5)Li(3)(+) are of the forms O(2)(-)(Li(+))(3)O(2)(-) and O(2)(-)(Li(+))(3)O(3)(-), respectively, both of which contain two monovalent ion units. The structural integrity of the central Y group and the arrangement of the lithium ligands are two influencing factors on the vertical electron affinities (EA(vert)) for the YLi(3)(+) species. The YLi(3)(+) cation, with its lithium ligands being distributed evenly or far from each other, tends to exhibit a low EA(vert) value, whereas a greater extent of cleavage of the central Y group leads to a higher EA(vert) value and even makes some species lose their superalkali nature.

9.
J Comput Chem ; 32(6): 1033-42, 2011 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-20941731

RESUMO

The geometrical structures, phosphorescence quantum yields, and electroluminescence (EL) efficiency of six iridium(III) complexes containing 2-phenylimidazo[1,2-a]pyridine ligand are investigated by density functional theory (DFT), which show a wide color tuning of photoluminescence from orange (λ(em) = 550 nm) to blue-green (λ(em) = 490 nm). The calculated results shed some light on the reasons of the remarkably manipulated excited-state and EL properties through substitution effect. The Mulliken charge calculation reveals that attached -CF(3) groups on phenyl and imidazo[1,2-a]pyridine (impy) moieties (4) can make both of them as electron-deficient region, which will lead to the contraction of the whole coordination sphere and strengthen the metal-ligand interaction. While attaching two -CF(3) groups on phenyl ring can make it more electron-deficient, which will induce electron transferring from acac and impy fragment to phenyl ring, and also result in the contracted structure. The largest metal-to-ligand charge transfer ((3)MLCT) character and the smaller S(1)-T(1) energy gap (ΔE(S(1)-T(1))) value increase the emission quantum yields of 4 and 6 than other complexes. For EL efficiency, because of the similar highest occupied molecular orbital (HOMO) levels of 4 and 6 to that of holes injection material poly(N-vinylcarbazole) (PVK) and the larger dipole moments, majority hole will be accumulated on the HOMO of 4 and 6. Combination with the lower lowest unoccupied molecular orbital energy levels compared with PVK, the recombination zones of 4 and 6 can be well confined within emitting material layer (EML) and lead to the higher EL efficiency.


Assuntos
Irídio/química , Luminescência , Compostos Organometálicos/química , Oxidiazóis/química , Teoria Quântica , Trinitrobenzenos/química , Cor , Ligantes , Medições Luminescentes , Estrutura Molecular , Estereoisomerismo
10.
Exp Gerontol ; 150: 111345, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-33836261

RESUMO

High-intensity interval training (HIIT) can effectively increase peak oxygen consumption, body composition, physical fitness, and health-related characteristics of adults; however, its impact in the older population remains highly debated. This review and meta-analysis aimed to evaluate the effects of high-intensity interval training on cardiorespiratory fitness, body composition, physical fitness, and health-related outcomes in older adults. Four electronic databases (PubMed, Scopus, Medline, and Web of Science) were searched (until July 2020) for randomized trials comparing the effect of HIIT on physical fitness, metabolic parameters, and cardiorespiratory fitness in older adults. The Cochrane risk of bias assessment tool was used to evaluate the methodological quality of the included studies; Stata 14.0 software was used for statistical analysis. HIIT significantly improved the maximum rate of oxygen consumption (VO2peak) as compared to a moderate-intensity continuous training (MICT) protocol (HIIT vs. MICT: weighted mean difference = 1.74, 95% confidence interval: 0.80-2.69, p < 0.001). Additional subgroup analyses determined that training periods >12 weeks, training frequencies of 2 sessions/week, session lengths of 40 min, 6 sets and repetitions, training times per repetition of >60 s, and rest times of <90 s were more effective for VO2peak. This systematic review and meta-analysis showed that HIIT induces favorable adaptions in cardiorespiratory fitness, physical fitness, muscle power, cardiac contractile function, mitochondrial citrate synthase activity, and reduced blood triglyceride and glucose levels in older individuals, which may help to maintain aerobic fitness and slow down the process of sarcopenia.


Assuntos
Aptidão Cardiorrespiratória , Treinamento Intervalado de Alta Intensidade , Idoso , Composição Corporal , Humanos , Aptidão Física , Ensaios Clínicos Controlados Aleatórios como Assunto
11.
J Phys Chem A ; 114(34): 9300-8, 2010 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-20684504

RESUMO

The origin of the rare and highly strong phosphorescent (PL) and electroluminescent (EL) Ir(III) complexes with C--N=N ligand, tris[3,6-bis(phenyl)pyridazinato-N(1),C(2)]iridium (Ir(BPPya)(3)) (1), tris[1,4-bis(phenyl)phthalazine]iridium (Ir(BPPa)(3)) (2), and tris[1-(2,6-dimethylphenoxy)-4-(4-chlorophenyl)phthalazine]iridium ((Ir(MPCPPZ)(3)) (3) are investigated theoretically. By changing the conjugation length of the C--N=N ligand from BPPya to BPPa, one can tune the emission color from green in 1 to saturated red in 2. The addition of sterically bulky phenolic substituents in 3 exhibits the highest external quantum efficiency of 20.2% ph el(-1) and luminescence efficiency of 18.4 cd A(-1). Density functional theory (DFT) and time-dependent DFT (TDDFT) methods are used to rationalize these properties. The more promising PL and EL properties of 3 result from the bulky phenolic group, which acts as a pendant at the periphery of the emitting core and protects the emitting core from the hazardous intermolecular interaction of emitters and reduces luminescence quenching.

12.
Mech Ageing Dev ; 189: 111262, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32422206

RESUMO

PURPOSE: This study aims to evaluate whether regular lifelong exercise has effects on age-related inflammatory cytokines, oxidative stress, and the skeletal muscle proteome. METHODS: Four groups of adult-aged (8-month-old) female Sprague Dawley rats were used: rats for which training was initiated at either 8 (8 M-MICT, moderate-intensity continuous training) or 18 months (18 M-MICT) and sedentary rats aged either 26 (26 M-SED) or 8 months (8M-SED), who served as aging and adult sedentary controls, respectively. Aged skeletal muscles were subjected to proteomic and Kyoto Encyclopedia of Genes and Genomes (KEGG) and immunoblotting analyses. RESULTS: Age-related loss of physical performance and anti-inflammatory steroid levels were lowest in the 8 M-MICT group, while the anti-oxidative activities remained unchanged compared to 18 M-MICT rats. The proteomic analysis demonstrated an amelioration of age-related changes to muscle contraction, focal adhesion signaling, mitochondrial function, apoptosis and regeneration, anti-oxidation, and protein processing in the endoplasmic reticulum in the 8 M-MICT. Additionally, neurotrophin (BDNF) and AKT/FOXO signaling pathways were upregulated in 8 M-MICT rats compared to 26 M-SED. CONCLUSION: 8 M-MICT exhibited greater beneficial effects in ameliorating age-related inflammation and physical performance loss, compared to 18 M-MICT. The amelioration is potentially related to the upregulation of autophagy activities via BDNF/AKT signaling.


Assuntos
Envelhecimento/metabolismo , Citocinas/metabolismo , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Estresse Oxidativo , Condicionamento Físico Animal , Proteoma/metabolismo , Animais , Feminino , Inflamação/metabolismo , Ratos , Ratos Sprague-Dawley
13.
Inorg Chem ; 48(16): 7740-9, 2009 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-19591441

RESUMO

Quantum-chemistry methods were explored to investigate the electronic structures, injection and transport properties, absorption and phosphorescence mechanism of a series of blue-emitting Ir(III) complexes {[(F(2)-ppy)(2)Ir(pta -X/pyN4)], where F(2)-ppy = (2,4-difluoro)phenylpyridine; pta = pyridine-1,2,4-triazole; X = phenyl(1); p-tolyl (2); 2,6-difluororophenyl (3); -CF(3) (4), and pyN4 = pyridine-1,2,4-tetrazolate (5)}, which are used as emitters in organic light-emitting diodes (OLEDs). The mobility of hole and electron were studied computationally based on the Marcus theory. Calculations of Ionization potentials (IPs) and electron affinities (EAs) were used to evaluate the injection abilities of holes and electrons into these complexes. The reasons for the lower EL efficiency and phosphorescence quantum yields in 3-5 than in 1and 2 have been investigated. These new structure-property relationships can guide an improved design and optimization of OLED devices based on blue-emitting phosphorescent Ir(III) complexes.


Assuntos
Irídio/química , Luz , Compostos Organometálicos/química , Teoria Quântica , Absorção , Cor , Eletrodos , Transporte de Elétrons , Elétrons , Injeções , Medições Luminescentes , Cloreto de Metileno/química , Modelos Moleculares , Conformação Molecular , Relação Estrutura-Atividade , Fatores de Tempo
14.
Phys Chem Chem Phys ; 11(42): 9687-95, 2009 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-19916258

RESUMO

In this paper, a quantum chemistry method was used to investigate the effect of different sizes of substituted phenanthrolines on absorption, energy transfer, and the electroluminescent performance of a series of Eu(TTA)(3)L (L = [1,10] phenanthroline (Phen), Pyrazino[2,3-f][1,10]phenanthroline (PyPhen), 2-methylprrazino[2,3-f][1,10]phenanthroline(MPP), dipyrido[3,2-a:2',3'-c]phenazine(DPPz), 11-methyldipyrido[3,2-a:2',3'-c]phenazine(MDPz), 11.12-dimethyldipyrido[3,2-a:2',3'-c]phenazine(DDPz), and benzo[i]dipyrido[3,2-a:2',3'-c]phenazine (BDPz)) complexes. Absorption spectra calculations show that different sizes of secondary ligands have different effects on transition characters, intensities, and absorption peak positions. The larger secondary ligands DPPz, MDPz, DDPz and BDPz lead to incomplete energy transfer from the triplet states of ligands to the (5)D(0) of the Eu(3+) ion compared with smaller ones (PyPhen and MPP) due to their lower S(1) or T(1) state energy levels than that of TTA or (5)D(0) of Eu(3+). "Small polaron" stabilization energy (SPE) results reveal that electron trapping is the dominant electroluminescence (EL) mechanism in these materials due to their lower LUMO energies than 4,4'-N,N'-dicarbazolebiphenyl (CBP). Reorganization energy (l) values show that these materials have better electron than hole transporting properties. In addition, the reasons for the origin of the 500 nm emission in Eu-PyPhen- and Eu-MPP-based OLED devices were investigated, and we suppose this emission may result from 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), not from Alq(3).

15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(1): 263-7, 2009 Jan.
Artigo em Zh | MEDLINE | ID: mdl-19385254

RESUMO

Flame atomic absorption spectrometry was applied to the determination of micro amount of lithium in the oil field water of certain area. In order to determine which method is more appropriate for the determination of lithium content in the oil field water, standard curve method and standard addition method were compared. The effects of dilution, coexistent ions, and deionizers on the determination were studied. For the determination of lithium content in the same diluted oil field water samples, there exist obvious differences between the results obtained from standard addition method and standard curve method. Standard addition method gives results with a larger error, whereas standard curve method gives more accurate results. It is difficult to eliminate the interferences when the standard addition method is used. The standard curve method is found to be more suitable for the determination of micro amount of lithium in the oil field water for its accuracy, simplicity, and feasibility. When the standard curve method is used, both the determined lithium concentration and the recovery change with the dilution extent of the oil field water. In order to get an accurate result, the oil field water sample should be diluted to 1/200 or less. In this case, the recovery by standard addition method ranges from 94.3% to 96.9%. When sodium phosphate or sodium chloride is used as the deionizer, the recovery by standard addition method ranges from 94.6% to 98.6%, or from 94.2% to 96.3%. In the determination of lithium content in oil field water, there are larger experimental errors without the addition of any deionizer. When the concentration of coexistent ions is within an allowed range, the addition of sodium phosphate as a deionizer can eliminate the interferences of the coexistent ions with the determination of the lithium content. If sodium chloride is used as a deionizer, a more accurate result can be obtained when the sodium content in the samples is near the sodium content in the standard solutions. In general, under suitable experimental conditions, sodium chloride can be used as the deionizer for the determination of lithium content in the oil field water.


Assuntos
Cálcio/análise , Lítio/análise , Cloretos/análise , Análise de Injeção de Fluxo , Óleos de Plantas/análise , Potássio/análise , Padrões de Referência , Sódio/análise , Cloreto de Sódio/análise , Soluções/análise , Espectrofotometria Atômica/métodos , Água
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(3): 833-6, 2009 Mar.
Artigo em Zh | MEDLINE | ID: mdl-19455837

RESUMO

Flame atomic absorption spectrometry (FAAS) was applied to the determination of rubidium and cesium in chloride type oilfield water by considering the interferences of the coexistent K+, Na+, Ca2+, and Mg2+ ions, Standard curve method and standard addition method were compared in the determination of rubidium and cesium in the simulated oilfield water and the real oilfield water from the Nanyishan region in Qaidam Basin. Although rubidium and cesium have similar physical-chemical properties, they present different characters during their analyses using the FAAS technique. When the standard addition method was used for the determination of rubidium and cesium in the simulated oilfield water, the results of rubidium were very poor, whereas the results of cesium were satisfactory. When the standard curve method was used for the determination of rubidium and cesium in the simulated oilfield water, the results of both rubidium and cesium were satisfactory within the linear ranges of the standard curves. For the real oilfield water, standard addition method is also only applicable for the determination of cesium with a recovery ranging from 90% to 110%. While standard curve method is applicable for the determination of both rubidium and cesium with a recovery ranging from 90% to 110%.

17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(10): 2829-32, 2009 Oct.
Artigo em Zh | MEDLINE | ID: mdl-20038070

RESUMO

The effect of flotation agent octadecyl amine (ODA) on the complex titration of both magnesium and calcium ions was studied with two groups of comparative experiments: (1) Before titration, the suspension was not filtered. In this case, ODA had a great effect on the complex titration of both magnesium and calcium ions. The titration end-point of magnesium ions was difficult to be determined. Although the titration end-point of calcium ions could be determined, there was an obvious experimental error compared with the blank solution without ODA. These results were confirmed by the UV-Visible spectrum analyses of the related solutions. (2) Before titration, the suspension was filtered. In this case, the influence of ODA on the complex titration of both magnesium and calcium ions could be removed. UV-Visible spectrum studies showed that, in this case, both the spectra and time scanning curves of the tested solutions were similar to those of the blank solutions.

18.
Zhong Xi Yi Jie He Xue Bao ; 7(10): 947-51, 2009 Oct.
Artigo em Zh | MEDLINE | ID: mdl-19828105

RESUMO

OBJECTIVE: To investigate the effects of extract of Bulbus Allii Caespitosi on cardiocyte viability of swines with myocardial reperfusion injury by analyzing the 18F-fluorodeoxyglucose ((18)F-FDG) position emission tomography (PET) imaging. METHODS: Twenty-four swines were randomly divided into sham-operated group, untreated group, trimethazine group and extract of Bulbus Allii Caespitosi group. Myocardial reperfusion injury was induced by plugging the anterior descending coronary artery of swine with sacculus. Bulbus Allii Caespitosi or trimetazidine was given twice daily for 28 days. Then myocardial perfusion was detected with (18)F-FDG PET/CT and the radioactivity distribution was evaluated. RESULTS: Compared with the untreated group, Bulbus Allii Caespitosi and trimetazidine could improve the activity of myocardial cells after myocardial infarction (P<0.01), and there were no significant differences between Bulbus Allii Caespitosi and trimetazidine (P>0.05). CONCLUSION: Bulbus Allii Caespitosi can improve myocardial metabolism after ischemia and reperfusion in swines.


Assuntos
Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Miocárdio/metabolismo , Extratos Vegetais/farmacologia , Animais , Fluordesoxiglucose F18 , Infarto do Miocárdio/fisiopatologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Tomografia por Emissão de Pósitrons , Suínos
19.
Zhonghua Nan Ke Xue ; 14(7): 602-5, 2008 Jul.
Artigo em Zh | MEDLINE | ID: mdl-18686379

RESUMO

OBJECTIVE: To study the changes of hypothalamus metabolism in patients with psychogenic erectile dysfunction (ED) so as to get some clues to the possible pathogenic factors and pathophysiological mechanism of the problem. METHODS: Six cases of psychogenic ED and 4 normal volunteers were studied by positron emission tomography (PET) for the characteristics of hypothalamus glucose metabolism. Following audiovisual sexual stimulation, the concentration of fluorine-18-fluorodeoxyglucose (18 F-FDG) was determined and the ratio of the left (right) hypothalamus count to the cerebrum count was calculated. RESULTS: Audiovisual sexual stimulation significantly increased 18F-FDG in the volunteers (left: 1.026 +/- 0.115 vs 2.400 +/- 0.210; right: 1.003 +/- 0.187 vs 2.389 +0.196, P < 0.05) as compared with the psychogenic ED patients (left: 2.781 +/- 0.156 vs 2.769 +/- 0.223; right: 2.809 +/- 0.129 vs 2.793 +/- 0.217, P > 0.05). CONCLUSION: Psychogenic ED may not be simply a functional disease; the hypothalamus may be involved in the pathophysiology of the problem.


Assuntos
Hipotálamo/diagnóstico por imagem , Disfunções Sexuais Psicogênicas/diagnóstico por imagem , Estimulação Acústica , Adulto , Recursos Audiovisuais , Fluordesoxiglucose F18/farmacocinética , Humanos , Hipotálamo/metabolismo , Hipotálamo/fisiopatologia , Masculino , Estimulação Luminosa , Disfunções Sexuais Psicogênicas/metabolismo , Disfunções Sexuais Psicogênicas/fisiopatologia , Tomografia Computadorizada de Emissão
20.
Zhonghua Yi Xue Za Zhi ; 87(32): 2253-6, 2007 Aug 28.
Artigo em Zh | MEDLINE | ID: mdl-18001544

RESUMO

OBJECTIVE: To assess the role of 2-[fluorine-18]-fluoro-2-deoxy-D-glucose ((18)F-FDG) positron emission tomography/computed tomography (PET/CT) in the management of unknown primary primary (CUP) with metastatic loci. METHODS: Thirty-four patients of CUP with metastatic loci who had undergone unsuccessful conventional diagnostic work-up underwent (18)F-FDG PET/CT. The images thus obtained were analyzed with visual and semi-quantitative methods. Histopathology, cytology, and/or follow-up were used to evaluate the PET/CT results. RESULTS: In 20 of the 34 patients (18)F-FDG PET/CT showed focal tracer accumulations corresponding to potential primary tumor sites located in the lung (n = 9), colon (n = 3), rectum (n = 2), pancreas (n = 1), right aryepiglottic wall (n = 1), esophagus (n = 1), breast (n = 1), and ovary (n = 2). The detection rate of primary tumor by (18)F-FDG PET/CT was 50.0% (17/34), the primary tumors were identified in the lung (n = 8), colon (n = 2), rectum (n = 1), pancreas (n = 1), right aryepiglottic wall (n = 1), esophagus (n = 1), ovary (n = 2), and breast (n = 1). The false positive rate was 8.8% (3/34) with the diagnosis of primary tumor in the lung (n = 1), colon (n = 1), and rectum (n = 1) to be identified as false. In 14 of the 34 patients, (18)F-FDG PET/CT did not reveal lesions suspected to be the primary tumor sites in 13 patients, and it was impossible to identify one lesion as the most likely primary tumor in one patient due to the presence of multiple hot spots in several organs. The (18)F-FDG PET/CT findings affected the medical management in 17 of the 34 (50.0%) patients due to the finding of primary sites and/or additional metastases. CONCLUSION: (18)F-FDG PET/CT has relevant impact on the therapeutic management of patients with unknown primary tumor. It is recommended that (18)F-FDG PET/CT be performed in the patient with unknown primary tumor after unsuccessful conventional diagnostic workup.


Assuntos
Fluordesoxiglucose F18 , Neoplasias Primárias Desconhecidas/diagnóstico , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
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