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91.
Background: Approximately 70% of rural Nigerian households rely on biomass fuels for cooking. The International Study of Asthma and Allergies in Childhood (ISAAC) estimates the prevalence of current wheeze among children in Nigeria to have risen from 10.7% in 1999 to approximately 20% in 2014. Objective: To examine the effects of biomass smoke exposure on asthma symptom prevalence in rural children in Nigeria. Methods: We conducted a cross-sectional survey in rural communities in Nigeria. Asthma symptoms were defined according to ISAAC definitions. Biomass smoke exposure was determined by the types of fuel used for cooking. Logistic regression was used to explore associations between biomass smoke and asthma symptoms. Results: The study population comprised 1,690 school children, of which 865 lived in households cooking with biomass and 825 lived in households not using biomass. Asthma symptoms were reported in 481 (28.5%) children. Biomass fuel was associated with increased odds of asthma symptoms. Adjusted odds ratios (aORs) were 1.38 (95% CI: 1.05–1.80) for nocturnal cough, 1.26 (95% CI: 1.00–1.61) for current wheeze, and 1.33 (95% CI: 1.05–1.69) for report of any asthma-related symptoms. Sex modified the associations between asthma symptoms with biomass fuel: aORs were stronger and significant for males (nocturnal cough = 1.85, 95% CI: 1.24–2.76; current wheeze = 1.48, 95% CI: 1.03–2.13; report of any asthma-related symptoms = 1.60, 95% CI: 1.12–2.28), but weaker and non-significant for females.Conclusion: The risk of asthma symptoms related to biomass smoke exposure appears to differ by sex. 相似文献
92.
Chaojun Xue Changyuan Wang Qi Liu Qiang Meng Huijun Sun Xiaokui Huo Xiaodong Ma Zhihao Liu Xiaochi Ma Jinyong Peng Kexin Liu 《Tumour biology》2016,37(7):8587-8597
P-glycoprotein (P-gp) is one of the major obstacles to efficiency of cancer chemotherapy. Here, we investigated whether combination of metformin and 2-deoxyglucose reverses the multidrug resistance (MDR) of K562/Dox cells and tried to elucidate the possible mechanisms. The combination of metformin and 2-deoxyglucose selectively enhanced the cytotoxicity of doxorubicin against K562/Dox cells. Metformin was not a substrate of P-gp but suppressed the elevated level of P-gp in K562/Dox cells. The downregulation of P-gp may be partly attributed to the inhibition of extracellular signal-regulated kinase pathway. The addition of 2-deoxyglucose to metformin initiated a strong metabolic stress in both K562 and K562/Dox cells. Combination of metformin and 2-deoxyglucose inhibited glucose uptake and lactate production in K562 and K562/Dox cells leading to a severe depletion in ATP and a enhanced autophagy. Above all, P-gp substrate selectively aggravated this ATP depletion effect and increased cell apoptosis in K562/Dox cells. In conclusion, metformin decreases P-gp expression in K562/Dox cells via blocking phosphorylation of extracellular signal-regulated kinase. P-gp substrate increases K562/Dox cell apoptosis via aggravating ATP depletion induced by combination of metformin and 2-deoxyglucose. Our observations highlight the importance of combination of metformin and 2-deoxyglucose in reversing multidrug resistance. 相似文献
93.
Jinhai Huo Thomas A. Aloia Ying Xu Tong Han Chung Tommy Sheu Ya-Chen Tina Shih 《Value in health》2019,22(3):284-292
Background
For patients with hepatocellular carcinoma (HCC) not eligible for surgical resection, radiofrequency ablation (RFA) is a promising technique that reduces the risk of disease progression.Objectives
To evaluate whether the trend of image guidance for RFA is moving toward the more expensive computed tomography (CT) technology and to determine the clinical benefits of CT guidance over the ultrasound (US) guidance.Methods
A cohort of 463 patients was identified from the Surveillance, Epidemiology, and End Results and Medicare–linked database. The temporal trends in use of image guidance were assessed using the Cochrane–Armitage test. The associations between modality of image guidance and survival, complications, and costs were assessed using the Cox regression model, the logistic regression model, and the generalized linear model, respectively.Results
The use of CT-guided RFA increased sharply, from 20.7% in 2002 to 75.9% in 2011. Compared with CT-guided RFA, those who received US-guided RFA had comparable risk of periprocedural and delayed postprocedural complications. Stratified analyses by tumor size also showed no statistically significant difference. In adjusted survival analysis, no statistically significant difference was observed in overall and cancer-specific survival. Nevertheless, the cost of CT-guided RFA ($2847) was higher than that of US-guided RFA ($1862).Conclusions
Despite its rapid adoption over time, CT-guided RFA incurred higher procedural costs than US-guided RFA but did not significantly improve postprocedural complications and survival. Echoing the American Board of Internal Medicine’s Choosing Wisely campaign and the American Society of Clinical Oncology’s Value of Cancer Care initiative, findings from our study call for critical evaluation of whether CT-guided RFA provides high-value care for patients with HCC. 相似文献94.
Venous thromboembolism (VTE) is the most common potentially preventable form of hospital-related mortality. It presents as
a major healthcare burden, affecting both medical and surgical patients. The prevention of VTE has been identified as one
of the most important in-hospital safety practices in the US. VTE guideline recommendations provide a framework for clinical
practice and guide VTE prophylaxis policies. Guidelines produced by the American College of Chest Physicians (ACCP) are considered
to be the ‘gold standard’ in VTE prevention, diagnosis and management, and have been updated. A number of differences exist
between the new 2008 ACCP guidelines on VTE prevention and the previous version published in 2004. There are variations regarding
VTE prevention, including new and stronger evidence-based recommendations for several indications and agents. The updated
guidelines give a strong recommendation that every hospital develop a VTE prevention policy, which is particularly important
given the current international drive to reduce the incidence of VTE. A formal hospital policy should help improve compliance
with appropriate VTE prophylaxis strategies. The ACCP guidelines form a basis for improving patient safety at a time of public
reporting of quality of care, hospital accreditation, national standards of care, and pay for performance initiatives. In
this review, changes in recommendations for VTE prevention in the 2008 ACCP guidelines compared with the previous edition
in 2004 are outlined. In addition, outstanding areas of debate are discussed and the role of the 2008 ACCP guidelines in the
context of the new VTE performance measures analyzed. 相似文献
95.
Ming-Cheng Luo Yong Q. Gu Frank M. You Karin R. Deal Yaqin Ma Yuqin Hu Naxin Huo Yi Wang Jirui Wang Shiyong Chen Chad M. Jorgensen Yong Zhang Patrick E. McGuire Shiran Pasternak Joshua C. Stein Doreen Ware Melissa Kramer W. Richard McCombie Shahryar F. Kianian Mihaela M. Martis Klaus F. X. Mayer Sunish K. Sehgal Wanlong Li Bikram S. Gill Michael W. Bevan Hana ?imková Jaroslav Dole?el Song Weining Gerard R. Lazo Olin D. Anderson Jan Dvorak 《Proceedings of the National Academy of Sciences of the United States of America》2013,110(19):7940-7945
96.
97.
Background:Patients with severe acute pancreatitis (SAP) have gastrointestinal dysfunction, and enteral nutrition intolerance is easy to occur during the implementation of enteral nutrition, which leads to the suspension or termination of enteral nutrition. Enteral nutrition cannot tolerate the influence of many factors. At present, there is a lack of analysis on the influencing factors of enteral nutrition intolerance in patients with SAP. Therefore, this study analyzed the factors of enteral nutrition intolerance in patients with SAP by meta-analysis, to provide a basis for the protection of enteral nutrition in patients with SAP.Methods:Databases (PubMed, Embase, Cochrane Library, Web of Science, China Biology Medicine Database, China National Knowledge Infrastructure, China Science and Technology Journal Database, and Wanfang) were searched using index words to find relevant studies published before March 2021. Meta-analyses of relative risk were performed for the identification of risk factors.Results:We will disseminate the findings of this systematic review and meta-analysis via publications in peer-reviewed journals.Conclusion:This study systematically reviewed the existing evidence and determined the incidence and predictors of enteral nutrition intolerance in patients with SAP. 相似文献
98.
炎性相关细胞因子和心肌梗死微循环再灌注状态的关系 总被引:7,自引:0,他引:7
目的 观察急性心肌梗死 (AMI)患者梗死相关血管 (IRA)开通前后炎性细胞因子的动态变化及其与心肌组织水平灌注状态的关系。方法 (1)测定 8例健康人和 2 2例AMI患者急诊冠状动脉介入治疗术 (PCI)前即刻 ,术后 12、2 4h ,血浆白细胞介素 (IL) 1β、肿瘤坏死因子 (TNF)α、IL 10的变化。 (2 )按照再灌注后 2h心电图ST段回落是否 >70 % ,将 2 2例AMI患者分为 :A组 (ST回落≥ 70 % )12例和B组 (ST回落 <70 % ) 10例 ,比较两组患者IL 1β、TNFα、IL 10的变化幅度。 结果 (1)治疗前A、B两组AMI患者血浆TNFα、IL 10略高于健康对照组 ,但差异无统计学意义 (P >0 0 5 ) ;而IL 1β显著高于健康对照组 (P <0 0 5 ) ;再灌注后 12、2 4hA、B两组血浆IL 1β和TNFα均较术前显著增高 (P <0 0 1,P <0 0 5 ) ,B组血浆IL 10较术前显著增高 (P <0 0 5 ) ,A组则无此变化 (P >0 0 5 )。 (2 )A、B两组间比较 ,治疗前TNFα、IL 1β、IL 10差异均无显著性 (P >0 0 5 ) ;成功PCI、IRA血流达TIMI 3级者 ,B组患者血浆IL 1β、TNFα、IL 10 ,在再灌注 12h显著高于A组 (P <0 0 1,P <0 0 5 ,P <0 0 5 ) ,再灌注 2 4h ,IL 1β、IL 10仍然高于A组 (P <0 0 5 )。 (3)A、B两组患者抗炎因子IL 10的升高幅度均显著低于致炎 相似文献
99.
T Huo M Q Ye D P Healy 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(8):3170-3174
Dopamine (DA) produces a natriuretic/diuretic response in the kidney by mechanisms that are still not well understood. There is some indication that DA2 receptors may be involved in mediating the effects of DA, but little is known regarding the nature of this receptor in the kidney. Autoradiographic localization of [3H]spiperone, a DA2 antagonist, indicated that high-density binding was restricted to inner medullary collecting ducts (IMCDs). [3H]Spiperone binding was saturable, high affinity (Kd, 17.2 +/- 1.65 nM), and high density (Bmax, 935 +/- 83 fmol per mg of protein). The photosensitive spiperone analogue N-(p-azido-m-[125I]iodophenethyl)spiperone labeled similar sized proteins of Mr = 120,000 in membranes prepared from the kidney inner medulla, striatum, and pituitary. However, the rank-order competition profile for the [3H]spiperone binding in the kidney inner medulla differed from the DA2 receptor in striatum and pituitary and, furthermore, RNA (Northern) blot analyses of kidney inner medullary RNA with brain DA2 receptor oligonucleotide probes were negative. Functionally, DA stimulated prostaglandin E2 production by IMCD cells, an effect that could be blocked by the DA2 antagonist domperidone. These results indicate that the kidney inner medulla expresses a functional DA receptor that may represent a newly identified DA receptor subtype (here designated DA2K). Moreover, these results suggest that the kidney inner medulla may be a significant site at which DA, either directly or indirectly, influences water and electrolyte excretion. 相似文献
100.
Jianli Liu Yonglin He Dan Liu Yin He Zhipeng Tang Hong Lou Yapeng Huo Xiangyu Cao 《RSC advances》2018,8(13):7280
Astilbin (ASN) is a flavonoid compound isolated from the rhizome of Smilax china L. (Smilacaceae). It has many bioactivities, such as selective immunosuppression, antioxidant, anti-hepatic injury, etc., and is widely used in traditional Chinese medical treatments. The interaction of ASN with bovine serum albumin (BSA) was studied in a physiological buffer (pH = 7.40) using multi-spectroscopic techniques in combination with molecular docking methods. UV-vis absorption measurements proved that a ASN–BSA complex could be formed. Fluorescence data revealed that ASN could strongly quench the intrinsic fluorescence of BSA in terms of a static quenching procedure. The process of binding was spontaneous and the binding occurred mainly through hydrogen bonding and van der Waals forces. The distance r between donor (BSA) and acceptor (ASN) was calculated to be 4.80 nm based on Förster''s non-radiative energy transfer theory. The binding constant (Ka = 7.31 × 104 mol L−1) and the number of binding sites (n ≈ 1) at 298 K suggested that ASN only occupied one site in BSA with high affinity. Moreover, the results of molecular docking indicated that ASN was more likely to be located in site I (sub-domain IIA) of BSA. The results of synchronous fluorescence and three-dimensional fluorescence spectra showed that ASN induced conformational changes of BSA. The findings would be beneficial for research on the transportation, distribution and some important bioactivities of ASN in the human body.The interaction of astilbin with bovine serum albumin was confirmed by multi-spectroscopic techniques and molecular docking methods. 相似文献