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1.
Huan Jing Ke Xue ; 42(3): 1298-1305, 2021 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-33742926

RESUMO

Volatile organic compounds (VOCs) play important roles in the formation of ozone and fine particles in the troposphere. Industrial parks emit significant amounts of VOCs in China, while few studies have characterized them. In the present study, a mobile platform was employed to measure the levels and composition VOCs around industrial parks in the Yangzte River Delta region. The average concentration of VOCs ranged from 39 µg·m-3 (5% percentile) to 533 µg·m-3 (95% percentile) with an average of 183 µg·m-3, which was three times that of ambient concentrations. Maximum VOC concentrations ranged from 307 µg·m-3 (5% percentile) to 12006 µg·m-3 (95% percentile) with an average of 2812 µg·m-3. The frequency of abnormal peak values was as high as 64% across all the industrial parks, of which toluene (32%), xylene (18%), benzene (9%), and>C9 aromatics (19%) were the most common species. Differences in VOC characteristics were observed among the different types of industrial parks. Specifically, highest concentrations of VOCs were observed in textile industrial parks followed by chemical, painting, and petrochemical industrial parks, and VOC concentrations in electronics industrial parks were the lowest. Importantly, species measured using the mobile platform only contributed~50% of VOCs present in ambient samples, indicating that the concentrations of VOCs in the industrial parks were underestimated overall. These results can inform measures to control VOC pollution in industrial parks in China.

2.
Jpn J Nurs Sci ; 18(1): e12376, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32896954

RESUMO

AIM: Workplace social capital refers to relationship networks formed by individuals in an organization through long-term mutually beneficial interactions and cooperation with members. These relationship networks can create value and resources for organizations and individuals. This current study aimed to explore the potential impact of workplace social capital on the association between perceived stress and professional identity in clinical nurses during the COVID-19 outbreak. METHODS: In this cross-sectional study, 308 Chinese clinical nurses filled out the Chinese Workplace Social Capital Scale, the Chinese Perceived Stress Scale, and the Chinese Nurse's Professional Identity Scale. Descriptive analysis, independent samples t test, analysis of variance, Pearson correlation analyses, and bootstrap method were performed to analyze the data. RESULTS: Perceived stress was negatively correlated with professional identity (r = -0.455, p < .001). Workplace social capital was not found to moderate the relationship between perceived stress and professional identity (95% CI -0.03 to- 0.06, p = .47 > .05). Instead, it mediated that relationship (95% CI -0.61 to -0.19, p < .05), and its mediating effect was -0.37. CONCLUSIONS: In the early stages of the COVID-19 outbreak, workplace social capital among the investigated clinical nurses failed to buffer the negative impact of perceived stress on professional identity, but it did play a part in mediating perceived stress and professional identity. A healthy workplace should be provided to clinical nurses to improve their professional identity, while lowering perceived stress.


Assuntos
COVID-19 , Capital Social , Estudos Transversais , Surtos de Doenças , Humanos , SARS-CoV-2 , Inquéritos e Questionários , Local de Trabalho
3.
Bioprocess Biosyst Eng ; 44(5): 995-1002, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33159544

RESUMO

To study the difference in transcriptome level of fatty acid metabolism pathway in Bamei pork and the difference of pork quality caused by the difference. In this study, Bamei pigs breeding in Huzhu farm of QingHai province were selected as the test object, compared with Gansu Black pigs. Four indexes of nutmeg acid (DX1), palmitic acid (DX2), stearic acid (DX3) and linoleic acid (DX4) were set. The expression profiles of fat metabolism related genes between the two groups samples were analysed by GCMS metabolomics and transcriptomics, then coexpression network analysis were conducted to obtain phenotypic related genes. The results showed that the metabolic levels of DX3 and DX4 were significantly higher than those of other fatty acids. Among these differences, the ENSSSCG00000024681 (G1) and ENSSSCG00000036883 (G2) genes play important regulatory roles in fatty acid metabolism, and the upregulated expression of their gene obviously affects the level of fatty acid metabolism, thereby affecting the quality and taste of pork. In addition, we found that there was a good correlation between the same lines, and the genetic traits of the hybrid lines of Bamei pig and Black pig are more inclined to Bamei pig. In the independent fatty acid metabolism, "Mg2+"and flavin adenine dinucleotide are more active, which plays an important role in energy utilization. Therefore, we can be inferred that the metabolism of stearic acid and linoleic acid are important fatty acids for pork quality. It also further confirms that the research method of combined omics is of great significance for the study of species traits and gene functions.


Assuntos
Ácidos Graxos , Metabolismo dos Lipídeos , Metaboloma , Carne de Porco , Transcriptoma , Animais , Especificidade da Espécie , Suínos
4.
Huan Jing Ke Xue ; 41(12): 5306-5315, 2020 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-33374046

RESUMO

The ambient concentration of 122 volatile organic compound (VOC) species were continuously measured in urban Hangzhou, China from May 2018 to April 2019. The average mixing ratio of VOCs was (59.4±23.6)×10-9 and the oxygenated VOCs (OVOC) were the largest component. There was no clear "weekend effect" in urban Hangzhou, while the concentration of VOCs had a sharp decrease during long holidays. The concentration of VOCs had a positive correlation with air quality index (AQI) and reached the highest level when the primary pollutant was PM2.5. The assessment results of atmospheric chemical reactivity with·OH radical loss rate (L·OH) and ozone formation potential (OFP) showed the average value of L·OH was 7.5 s-1 and that of OFP was 152.1×10-9, among which carbonyl compounds, aromatics, and alkenes were the most abundant components. The overall chemical reactivity level of VOCs in Hangzhou was equivalent to 2-methylpentane. The average value of toluene/benzene (T/B) was 1.95, which implied the ambient VOCs in Hangzhou were influenced by vehicle exhaust. Secondary formation (17.6%), combustion (11.8%), industrial processing (12.3%), solvent use (18.1%), biogenic source (4.5%), and vehicle exhaust (35.7%) were identified as six major sources of VOCs in Hangzhou through the positive matrix factorization (PMF) model.

5.
Huan Jing Ke Xue ; 41(7): 3076-3084, 2020 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-32608879

RESUMO

An intensive observation of ambient volatile organic compounds (VOCs) was carried out in Hangzhou, a key city in the Yangtze River Delta, during a typical photochemical pollution episode from September 14-23, 2018. The analysis results of 80 effective samples showed that the average concentration of 122 compounds of VOCs was (59.5±19.8)×10-9 during the observation period, and oxygenated VOCs (OVOCs) were the most abundant component. The assessment results of atmospheric reaction activity with ozone formation potential (OFP) showed that the average value of OFP was 145×10-9 during the observation period, of which alkenes and carbonyl compounds were the most abundant components. The chemical reactivity of VOCs in Hangzhou was equivalent to acrylonitrile. Based on the positive matrix factorization (PMF) model, five major sources of VOCs in Hangzhou were identified, including secondary formation (25.2%), combustion and industrial processing (27.2%), solvent use (17.3%), biogenic sources (9.2%), and vehicular exhaust (21.2%). The results can provide guidance for further understanding of VOC characteristics and the basis for scientific prevention and control measures in Hangzhou.

6.
Huan Jing Ke Xue ; 40(4): 1627-1633, 2019 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-31087902

RESUMO

Volatile organic compounds (VOCs) do great harm to human health, and also have some impact on air quality. Cooking is one of the important sources of VOCs, so the study of cooking emissions is of great significance. By simulating the heating of oil and cooking, the characteristics and chemical composition of VOCs emissions for different types of oil fumes were analyzed by gas chromatography-mass spectrometry (GC-MS), using different oils, seasonings, and dishes as variables. The results show that the emission factors of the oils range from 0.81 to 2.53 g·kg-1, and the emissions are dominated by halogenated hydrocarbons and alkanes. The emission factors of the seasonings range from 25.06 to 40.18 g·kg-1, and the seasonings mainly emit alkanes. The quantity of emissions from chili fried meat is much higher than that of tomato scrambled eggs, and the chili fried meat mainly emits halogenated hydrocarbons, while tomato scrambled eggs mainly emit aromatic hydrocarbons and alkanes.

7.
Huan Jing Ke Xue ; 39(5): 1978-1986, 2018 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965495

RESUMO

Particulate organic matter (POM) has attracted increasing attention recently due to its great contribution to fine particles (PM2.5) and complex components and sources. In the present study, 78 particulate organic compounds in PM2.5 were quantified at three sites in Shanghai during summer; these sites were located in urban (Xuhui), suburban (Qingpu), and coastal (Lin'gang) areas of the city. Accordingly, the chemical composition and spatial distribution were investigated and sources were explored based on the indicators and diagnostic ratios combined with backward trajectory. The results showed that during the period of observation, the quantified organic matter in the suburban area is about 319 ng ·m-3, close to the urban area but much higher than that of the coastal areas. Fatty acids were the largest contributors, followed by levoglucosan, polycyclic aromatic hydrocarbons (PAHs), n-alkanes, and hopanes. Source analysis based on tracer methods indicates that gasoline vehicle emissions were the main source of POM in Shanghai. Biomass burning from the northeast impacted somewhat on the urban area and western suburbs during the observation period. Terrestrial plant emissions played an important role in the source of fatty acids at Qingpu and Lin'gang, and emissions of marine phytoplankton and microorganisms were also important for fatty acids at Lin'gang. Coal combustion and motor vehicle exhaust made an important contribution to PAHs according to an analysis of diagnostic ratios. This study presented the characteristics and sources of POM in summertime Shanghai, which facilitates the development of an effective control strategy on PM2.5 pollution.

8.
Food Chem ; 244: 371-377, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29120796

RESUMO

A specific, precise and accurate high performance liquid chromatographic (HPLC) analytical method with a fluorescence detector (FLD) was established for the simultaneous determination of nine bisphenols (BPs) in milk samples. Samples were extracted ultrasonically with acetonitrile and cleaned using the QuEChERS technique. Under the optimized conditions, good linearity was obtained for the nine BPs and the correlation coefficients (R2) ranged from 0.9942 to 0.9997. Recovery values for the nine bisphenols in spiked samples were 75.82-93.86% with intra-day and inter-day relative standard deviations (RSDs) from 2.6 to 11.1%. The limits of detection (LODs) and quantification (LOQs) were 1.0-3.1 µg/kg and 3.5-9.8 µg/kg, respectively. The results demonstrated clearly that the approach developed provides reliable, simple, rapid and environmentally-friendly quantification and identification of nine bisphenols in a fatty matrix and could be used for monitoring bisphenols in milk.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Leite/química , Fenóis/análise , Animais , Compostos Benzidrílicos/análise , Fluorescência , Limite de Detecção
9.
JAMA ; 317(24): 2502-2514, 2017 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-28655015

RESUMO

Importance: Acupuncture is used to induce ovulation in some women with polycystic ovary syndrome, without supporting clinical evidence. Objective: To assess whether active acupuncture, either alone or combined with clomiphene, increases the likelihood of live births among women with polycystic ovary syndrome. Design, Setting, and Participants: A double-blind (clomiphene vs placebo), single-blind (active vs control acupuncture) factorial trial was conducted at 21 sites (27 hospitals) in mainland China between July 6, 2012, and November 18, 2014, with 10 months of pregnancy follow-up until October 7, 2015. Chinese women with polycystic ovary syndrome were randomized in a 1:1:1:1 ratio to 4 groups. Interventions: Active or control acupuncture administered twice a week for 30 minutes per treatment and clomiphene or placebo administered for 5 days per cycle, for up to 4 cycles. The active acupuncture group received deep needle insertion with combined manual and low-frequency electrical stimulation; the control acupuncture group received superficial needle insertion, no manual stimulation, and mock electricity. Main Outcomes and Measures: The primary outcome was live birth. Secondary outcomes included adverse events. Results: Among the 1000 randomized women (mean [SD] age, 27.9 [3.3] years; mean [SD] body mass index, 24.2 [4.3]), 250 were randomized to each group; a total of 926 women (92.6%) completed the trial. Live births occurred in 69 of 235 women (29.4%) in the active acupuncture plus clomiphene group, 66 of 236 (28.0%) in the control acupuncture plus clomiphene group, 31 of 223 (13.9%) in the active acupuncture plus placebo group, and 39 of 232 (16.8%) in the control acupuncture plus placebo group. There was no significant interaction between active acupuncture and clomiphene (P = .39), so main effects were evaluated. The live birth rate was significantly higher in the women treated with clomiphene than with placebo (135 of 471 [28.7%] vs 70 of 455 [15.4%], respectively; difference, 13.3%; 95% CI, 8.0% to 18.5%) and not significantly different between women treated with active vs control acupuncture (100 of 458 [21.8%] vs 105 of 468 [22.4%], respectively; difference, -0.6%; 95% CI, -5.9% to 4.7%). Diarrhea and bruising were more common in patients receiving active acupuncture than control acupuncture (diarrhea: 25 of 500 [5.0%] vs 8 of 500 [1.6%], respectively; difference, 3.4%; 95% CI, 1.2% to 5.6%; bruising: 37 of 500 [7.4%] vs 9 of 500 [1.8%], respectively; difference, 5.6%; 95% CI, 3.0% to 8.2%). Conclusions and Relevance: Among Chinese women with polycystic ovary syndrome, the use of acupuncture with or without clomiphene, compared with control acupuncture and placebo, did not increase live births. This finding does not support acupuncture as an infertility treatment in such women. Trial Registration: clinicaltrials.gov Identifier: NCT01573858.


Assuntos
Terapia por Acupuntura , Clomifeno/uso terapêutico , Fármacos para a Fertilidade Feminina/uso terapêutico , Infertilidade Feminina/terapia , Nascido Vivo/epidemiologia , Síndrome do Ovário Policístico/terapia , Terapia por Acupuntura/efeitos adversos , Terapia por Acupuntura/estatística & dados numéricos , Adulto , Índice de Massa Corporal , Clomifeno/efeitos adversos , Terapia Combinada/métodos , Contusões/etiologia , Diarreia/etiologia , Método Duplo-Cego , Esquema de Medicação , Feminino , Fármacos para a Fertilidade Feminina/efeitos adversos , Humanos , Infertilidade Feminina/tratamento farmacológico , Infertilidade Feminina/etiologia , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/tratamento farmacológico , Gravidez , Método Simples-Cego , Fatores de Tempo
10.
Meat Sci ; 105: 96-107, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25828164

RESUMO

A liquid chromatography with tandem mass spectrometric detection (LC-MS/MS) method was established for the simultaneous determination of the levels of 10 ß2-agonists in meat. The samples were extracted using an aqueous acidic solution and cleaned up using a Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) technique utilising a DVB-NVP-SO3Na sorbent synthesised in-house. First, the ß2-agonist residues were extracted in an aqueous acidic solution, followed by matrix solid-phase dispersion for clean-up. The linearities of the method were R(2)=0.9925-0.9998, with RSDs of 2.7-15.3% and 73.7-103.5% recoveries. Very low limits of detection (LOD) and quantitation (LOQ) of 0.2-0.9 µg/kg and 0.8-3.2 µg/kg, respectively, were achieved for spiked meat. The values obtained were lower than the maximum residue limits (MRLs) established by the EU and China. These results clearly demonstrate the feasibility of the proposed approach. The evaluated method provided reliable screening, quantification and identification of 10 ß2-agonists in meat.


Assuntos
Agonistas de Receptores Adrenérgicos beta 2/análise , Resíduos de Drogas/análise , Etanolaminas/análise , Contaminação de Alimentos , Inspeção de Alimentos/métodos , Carne/análise , Fenetilaminas/análise , Agonistas de Receptores Adrenérgicos beta 2/química , Métodos Analíticos de Preparação de Amostras , Animais , Bovinos , China , Cromatografia Líquida de Alta Pressão , Resíduos de Drogas/química , Etanolaminas/química , União Europeia , Inspeção de Alimentos/normas , Resinas de Troca Iônica/síntese química , Resinas de Troca Iônica/química , Limite de Detecção , Carne/normas , Estrutura Molecular , Fenetilaminas/química , Reprodutibilidade dos Testes , Extração em Fase Sólida , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
11.
Beijing Da Xue Xue Bao Yi Xue Ban ; 36(2): 215-7, 2004 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-15100747

RESUMO

OBJECTIVE: To study the relationship between malignant transformation and fertilization types of hydatidiform moles (HM). METHODS: Fifty four HM specimens were analyzed by using multiplex STR-PCR (9 loci) to determine the fertilization types and all patients were followed-up for the human chorionic gonadotropin (hCG) over 1 year. RESULTS: Total malignant transformation cases were 10 in all the 54 HM. Ggenetics complete hydatidiform moles (g-CHM) with DNA from only paternal origin, were observed in 38 cases including 28 homozygote and 10 heterozygote cases. In homozygote and heterozygote cases,malignant transformation occurred in 8 cases of the empty eggs fertilized by single sperms and 2 by double sperms respectively. In all the 54 HMs, 16 cases of DNA from parents were genetic partial hydatidiform moles (g-PHM), and no malignant transformation occurred in each haploidy egg fertilized by double sperms. CONCLUSION: (1)Genetic complete hydatidiform moles (g-CHM) showed a higher malignant transformation risk than genetic partial hydatidiform moles (g-PHM) (P=0.024 2); (2)There was no significant difference in malignant transformation between homozygote and heterozygote of g-CHM (P=0.699).


Assuntos
Fertilização , Mola Hidatiforme/genética , Neoplasias Uterinas/genética , Transformação Celular Neoplásica , Feminino , Humanos , Mola Hidatiforme/patologia , Mola Hidatiforme/fisiopatologia , Reação em Cadeia da Polimerase , Gravidez , Sequências de Repetição em Tandem , Neoplasias Uterinas/parasitologia , Neoplasias Uterinas/fisiopatologia
12.
Zhonghua Yi Xue Za Zhi ; 83(8): 666-8, 2003 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-12887825

RESUMO

OBJECTIVE: To explore the expression of leptin, leptin receptor (Ob-R) and related signaling proteins in woman reproductive organs. METHODS: Thirty-nine women, aged 27 - 37, with normal menstrual cycle of which 24 being in proliferative phase and 15 in secretive phase, underwent uterine curettage, to obtain the endometrium. The uterine cervix, vaginal wall, and oviducts were resected from 3 women with hysteromyoma. The expression of mRNA of leptin and long isoform of leptin receptor (Ob-Rb) was detected by in situ hybridization. The expression of leptin and Ob-Rb proteins was examined by immunohistochemical staining. Immunohistochemical staining was used to study the expression of the leptin-related signaling proteins: phosphated signal transducers and activator of transcription (p-STAT3), suppressor of cytokine signaling 3 (SOCS3), and protein inhibitor of activated STAT3 (PIAS3). RESULTS: The mRNA and protein of leptin and the mRNA and protein of Ob-Rb were expressed in the glands and mesenchyma of endometrium. The expression of Ob-Rb protein was significantly stronger in secretive phase than in proliferative phase (P < 0.01). No significant difference was found between the expression of leptin protein in proliferative phase and that in secretive phase. In the endothelium SOCS3 and PIAS3 were expressed, however, p-STAT3 protein was only weakly expressed or not expressed. Leptin protein and Ob-Rb protein were expressed in the uterine cervix, vagina wall, and epithelium of oviduct, including glands. However, leptin mRNA and Ob-Rb mRNA were only expressed in the ciliated epithelium of oviduct. CONCLUSION: Leptin may have an effect on women's reproductive function through leptin receptor systems.


Assuntos
Genitália Feminina/metabolismo , Leptina/genética , RNA Mensageiro/análise , Receptores de Superfície Celular/genética , Proteínas Repressoras , Fatores de Transcrição , Adulto , Proteínas de Transporte/fisiologia , Endométrio/metabolismo , Feminino , Humanos , Proteínas/fisiologia , Receptores para Leptina , Transdução de Sinais , Proteína 3 Supressora da Sinalização de Citocinas , Proteínas Supressoras da Sinalização de Citocina
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