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1.
Sci Total Environ ; 867: 161509, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36638982

RESUMO

The Tibetan Plateau is the third pole of the world, with an essential role in regulating Northern Hemisphere climate. Previous studies showed that atmospheric aerosols over the Tibetan Plateau are influenced by biomass burning (BB) products from South and Southeast Asia. In fact, open biomass burning (OBB) is also an important form of BB in Southeast Asian countries, causing serious springtime air pollution yearly. However, there are still scientific gaps in the contribution of OBB to surrounding regional aerosols, especially on the Tibetan Plateau. In order to quantify this contribution, we collected samples of fine particulate matter and derived the concentrations of major water soluble ion, water soluble organic carbon (WSOC), and total carbon (TC) and total nitrogen (TN) as well as the dual isotopic compositions of carbon and nitrogen (δ13C and δ15N) during March-June on the southeastern Tibetan Plateau. δ13C and δ15N showed no significant difference (p > 0.05) between the OBB and non-OBB periods. Furthermore, both δ13C and δ15N (-25.7 ± 0.7 ‰ and 8.0 ± 3.6 ‰) values calculated during the whole sampling period were similar to the BB value, indicating that the primary source of TC and TN in aerosols was BB, whether OBB or non-OBB burning periods. TC and TN concentrations during the OBB period (6.5 ± 2.9 µg m-3 and 1.2 ± 0.4 µg m-3, respectively) were significantly higher than during the non-OBB period (4.1 ± 1.7 µg m-3, with p = 0.014, and 0.7 ± 0.3 µg m-3, with p = 0.013, respectively). Active fire data and surface smoke concentrations further indicated that BB emissions from Southeast Asia were higher during the OBB period. This suggests that OBB-related high BB emissions significantly enhanced atmospheric aerosols concentrations on the southeastern Tibetan Plateau.

2.
Zhongguo Dang Dai Er Ke Za Zhi ; 23(3): 248-253, 2021 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-33691917

RESUMO

OBJECTIVE: To study the association of different stages of histological chorioamnionitis (HCA) with the incidence rate and severity of respiratory distress syndrome (RDS) in preterm infants. METHODS: Related data were collected from the infants and their mothers who were treated in the Neonatal Intensive Care Unit of Qingdao Women and Children's Hospital, Qingdao University, from January 2018 to June 2020. According to the presence or absence of HCA and its stage, the infants were divided into four groups: control (n=109), early-stage HCA (n=126), middle-stage HCA (n=105), and late-stage HCA (n=36). The four groups were compared in terms of gestational age, birth weight, sex, maternal age, placental abruption, prenatal use of antibiotics, and incidence rate of RDS. The correlation between HCA stage and RDS severity was analyzed. RESULTS: Compared with the control and late-stage HCA groups, the early-stage HCA group had a significantly lower incidence rate of placental abruption and a significantly higher rate of prenatal use of antibiotics (P < 0.05), and the early-stage HCA group had a significantly lower incidence rate of RDS than the control group (P < 0.05). The multivariate logistic regression analysis showed that early-, middle-, and late-stage HCA were protective factors against RDS (P < 0.05). The Spearman test showed that the severity of RDS in preterm infants was not correlated with the HCA stage (P > 0.05). CONCLUSIONS: Early-, middle-, and late-stage HCA can reduce the incidence rate of RDS in preterm infants. HCA stage may not be correlated with RDS severity in preterm infants, which needs to be verified by further research.


Assuntos
Corioamnionite , Síndrome do Desconforto Respiratório do Recém-Nascido , Peso ao Nascer , Criança , Corioamnionite/epidemiologia , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro , Gravidez , Síndrome do Desconforto Respiratório do Recém-Nascido/epidemiologia , Síndrome do Desconforto Respiratório do Recém-Nascido/etiologia
3.
Artif Cells Nanomed Biotechnol ; 49(1): 71-82, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33423558

RESUMO

Hydrogel serve as bone tissue engineering have lately received great attention for their good biocompatibility and structures similar to natural extracellular matrices. However, a single component polymer hydrogel is generally detrimental to cell adhesion due to the weaker mechanical properties, which limits their application considerably. In an effort to overcome this disadvantage, we adopt an unconventional dual network hydrogels consisting of the polyethylene glycol diacrylate (PEGDA) covalent network, a thiolated chitosan (TCS) ion crosslinking network and thiolated halloysites (T-HNTs) as reinforcing filler. In addition, bone morphogenetic protein-2 (BMP-2) was loaded into the prepared dual network (DN) hydrogel to improve the bone regeneration function of the DN hydrogel. The resulting PEGDA/TCS/T-HNTs hydrogels showed favourable mechanical property, higher crosslinking density, the lower swelling degree, excellent biocompatibility and cell adhesion ability. The histomorphometric and immunohistochemical analyses revealed the excellent bone regeneration ability for composite hydrogel after implant into rat skull defect. Thus, our results indicated that composite scaffold can be applied as a new bone regeneration biomaterial to be applied as a local drug delivery system with good bone induction performance.


Assuntos
Proteína Morfogenética Óssea 2 , Regeneração Óssea/efeitos dos fármacos , Quitosana , Argila/química , Hidrogéis , Polietilenoglicóis , Crânio , Animais , Proteína Morfogenética Óssea 2/química , Proteína Morfogenética Óssea 2/farmacologia , Linhagem Celular , Quitosana/química , Quitosana/farmacologia , Hidrogéis/química , Hidrogéis/farmacologia , Camundongos , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Ratos , Ratos Sprague-Dawley , Crânio/lesões , Crânio/metabolismo
4.
BMC Musculoskelet Disord ; 16: 21, 2015 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-25887534

RESUMO

BACKGROUND: Single administration of intra-articular (IA) bupivacaine for pain relief after arthroscopic knee surgery is effective, but its active duration and dose-response relationship is unclear. We conducted this meta-analysis to summarize all published randomized controlled trials (RCTs), thus providing the most recent information on the safety and efficacy of single-administration IA bupivacaine for pain relief after arthroscopic knee surgery, and to determine whether a dose-response relationship exists. METHODS: A systematic electronic literature search (through April 2014) was conducted to identify those RCTs that addressed the safety and efficacy of a single administration of IA bupivacaine for pain management after arthroscopic knee surgery. Subgroup analysis was conducted to determine changes in visual analog scale (VAS) scores at seven postoperative time points. Meta-regression and subgroup analyses were carried out to assess the effects of various treatment factors on efficacy and to evaluate the dose-response relationship of bupivacaine. Weighted mean differences or relative risks were calculated and pooled using a random-effects model. RESULTS: Twenty-eight trials involving 1,560 patients who underwent arthroscopic knee surgery met the inclusion criteria. The trials were subject to medium risk of bias. VAS scores at 2, 4, 6, 12, and 24 h postoperatively were significantly lower, the number of patients requiring supplementary analgesia was smaller, and the time to first request for analgesia was longer in the IA bupivacaine group than in the placebo group. The analgesic effect of single-administration IA bupivacaine may be associated with the effect of concomitant administration of epinephrine and concentration of bupivacaine, and no dose-response relationship was identified. No significant difference in side effects was detected between groups. CONCLUSIONS: Current evidence shows that the use of single-administration IA bupivacaine is effective for postoperative pain management in patients undergoing arthroscopic knee surgery, with satisfactory short-term safety. Low-dose administration of IA bupivacaine 0.5% combined with epinephrine adjuvant in clinical practice should be performed. Additional high-quality RCTs with longer follow-up periods are required to examine the safety of single-administration IA bupivacaine.


Assuntos
Anestésicos Locais/administração & dosagem , Artroscopia/efeitos adversos , Bupivacaína/administração & dosagem , Dor Pós-Operatória/prevenção & controle , Anestésicos Locais/efeitos adversos , Bupivacaína/efeitos adversos , Relação Dose-Resposta a Droga , Humanos , Injeções Intra-Articulares , Medição da Dor
6.
Zhonghua Yi Shi Za Zhi ; 36(2): 72-4, 2006 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-17096981

RESUMO

Since there are only very few Chinese medical literature in the Han and preceding dynasties extant, it is very difficult to investigate the origins of both the herbs and formulas in the book Shanghan Zabing Lun (Treatise on Cold Pathogenic and Miscellaneous Disease) and the status of that of the contemporary period. The Chinese medical bamboo slips of the Han dynasty unearthed from the tombs in Wuwei, Gansu Province in 1972, had been speculated by archeologists to be a medical literature written in the early period of the Eastern Han Dynasty, or, 150 years earlier than the time Zhang Zhongjing's book written at the end of the Eastern Han dynasty, Thus, it can provide evidence for the study on the source of herbs and formulas in Shanghan Zabing Lun.


Assuntos
Medicamentos de Ervas Chinesas/história , Formulários Farmacêuticos como Assunto/história , China , História do Século XIX , História do Século XX , Medicina Tradicional Chinesa/história
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