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A scoping review of maternal mortality,its health determinants,and factors that influence care utilization in women of child-bearing years in Nigeria
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作者 Sarah Ifunaya Anumudu Chijioke Christopher Uhegwu Christian Kosisochukwu Anumudu 《Global Health Journal》 2025年第3期185-199,共15页
Objectives:This scoping review aims to methodically identify and analyse the determinants which influence maternal mortality and healthcare utilization in women of childbearing years in Nigeria.The review specifically... Objectives:This scoping review aims to methodically identify and analyse the determinants which influence maternal mortality and healthcare utilization in women of childbearing years in Nigeria.The review specifically addresses the difficulties faced in assessing medical care,and the ongoing initiatives to lower the maternal mortality ratio.Methods:Primary studies(published after year 2000)focused on maternal mortality,health determinants,and the utilization of maternal healthcare services in Nigeria were retrieved following a systematic search across multiple databases,including Scopus,PubMed,Google Scholar,and Web of Science.These were screened using defined inclusion and exclusion criteria.Data from these studies were extracted and thematically analysed to identify common themes and trends.Results:A total of 21 publications were included in this review comprising 2 qualitative,17 quantitative,and2 mixed study designs.Major health determinants identified in these studies include hypertensive disorders of pregnancy,haemorrhage,and sepsis/septicaemia,contributing as much as 29%,24%,and 14.2%of maternal deaths respectively in over 10%of the reviewed studies.Similarly,social-economic determinants including poverty,maternal education,health system issues and culture significantly impacted the utilization of maternal healthcare services,inadvertently impacting maternal mortality.Despite various maternal health interventions such as the"Abiye"Safe Motherhood Initiative,the Integrated Maternal,Newborn,and Child Health Strategy and strengthening emergency obstetric care by governmental and non-governmental agencies,early childbearing,unemployment,large family sizes,and dependence on male spouses continued to result in suboptimal utilization of services and adverse maternal outcomes.Conclusion:This scoping review comprehensively integrated existing data from published studies to provide a detailed picture of maternal mortality,its health determinants,and factors influencing care utilization among women of childbearing age in Nigeria and approaches to reduce maternal mortality in the country and possibly in the West African sub-region. 展开更多
关键词 Maternal mortality Health determinants Hypertensive disorders of pregnancy HAEMORRHAGE Social determinants Maternal healthcare utilization Socioeconomic factors NIGERIA
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Improved Bound of the Fourth Hankel Determinant for a Class of Analytic Functions with Bounded Turnings Involving Cardioid Domain
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作者 Dong GUO Huo TANG +1 位作者 Xi LUO Zongtao LI 《Journal of Mathematical Research with Applications》 2025年第1期39-55,共17页
In the paper,a class of functions with bounded turnings involving cardioid domain,are studied in the region of the unit disc.The bounds of|a_(5)|,|a_(6)|,|a_(7)|and the fourth Hankel determinant are obtained,which are... In the paper,a class of functions with bounded turnings involving cardioid domain,are studied in the region of the unit disc.The bounds of|a_(5)|,|a_(6)|,|a_(7)|and the fourth Hankel determinant are obtained,which are more accurate than those obtained by Srivastava. 展开更多
关键词 analytic functions starlike functions convex functions Schwarz function cardioid domain Hankel determinant
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Prevalence and Determinants of Erectile Dysfunction in Adult Diabetic Patients in the Southwest Region of Cameroon
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作者 Divine Enoru Eyongeta Cyril Kamadjou +3 位作者 Boris Amougou Oteh Njockawoh Mpey Glennis T. Ayuk Fru F. Angwafo III 《Journal of Biosciences and Medicines》 2025年第2期413-426,共14页
Background: Erectile dysfunction (ED) is a common, bothersome and relatively under diagnosed complication of diabetes mellitus. This study was aimed to determine the prevalence of erectile dysfunction and its determin... Background: Erectile dysfunction (ED) is a common, bothersome and relatively under diagnosed complication of diabetes mellitus. This study was aimed to determine the prevalence of erectile dysfunction and its determinants. Methods: A cross-sectional hospital-based study was carried out in the Diabetology Units of the Buea and Limbe Regional Hospitals involving 332 male patients with diabetes and aged over 21 years. Data was analyzed using Stata and R version 3.5.3. Results: The mean age of the participants was 55years. Most participants (64.46%) were married. About half (50.60%) of the participants actively consumed alcohol, 11.45% were smokers and 57.83% were sedentary. 18 participants (5.42%) recorded high risk sexual behaviour. 54.32% of participants had a comorbidity and 43.90% were overweight. The prevalence of diabetic ED was 78.92%. Age, Fasting Blood Sugar and Glycated hemoglobin were found to be positive determinants of diabetic ED (odds ratio (OR) = 0.77, 95% CI −0.1 - 0.07). Conclusion: The prevalence of diabetic ED in this hospital population study is high, and both physician and patient—initiated measures are needed to reduce this prevalence and improve awareness, recognition and care of this condition. 展开更多
关键词 Erectile Dysfunction Diabetes Mellitus PREVALENCE determinants
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Homocysteine Levels and Determinants among Chinese Women at Mid-pregnancy, Late Pregnancy, and Postpartum
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作者 Zhenyu Guo Hongtian Li +3 位作者 Yirui Ma Ying Meng Yubo Zhou Jianmeng Liu 《Biomedical and Environmental Sciences》 2025年第4期459-468,共10页
Objective Data on homocysteine(Hcy) status and its determinants are limited among women during pregnancy and postpartum. This cross-sectional study aimed to investigate Hcy levels during pregnancy and postpartum, and ... Objective Data on homocysteine(Hcy) status and its determinants are limited among women during pregnancy and postpartum. This cross-sectional study aimed to investigate Hcy levels during pregnancy and postpartum, and to explore the determinants like geographic factor.Methods This study was conducted in women at mid-pregnancy, late-pregnancy and postpartum from southern, central and northern China. Approximately 132 women were included in each stratum by the three phases and regions. Plasma Hcy concentrations were assessed using high-performance liquid chromatography(HPLC), with hyperhomocysteinemia defined as > 10.0 μmol/L. Quantile regression was to estimate medians and interquartile ranges(IQRs), and logistic regression to examine the determinants of hyperhomocysteinemia.Results For 1,190 women included, the median(IQR) Hcy concentration was 5.66(4.62, 7.37) μmol/L.The adjusted median in mid-pregnancy, late-pregnancy and postpartum women was 4.75(4.13, 5.54),5.72(4.81, 6.85) and 7.09(5.65, 8.75) μmol/L, respectively, showing an increasing trend(P < 0.001). This increasing trend persisted across the three regions. Higher Hcy concentrations were observed in women residing in northern region and those with younger age or lower economic status. A total of 106(8.9%)women had hyperhomocysteinemia, with a higher prevalence in those residing in northern region(16.0%), or in postpartum women(16.5%).Conclusion Hcy levels, varying with geographic region, maternal age and economic status, are increased from mid-pregnancy to late-pregnancy and postpartum, indicating a need to monitor Hcy levels in pregnant and postpartum women to control potential risks related to elevated Hcy levels. 展开更多
关键词 HOMOCYSTEINE HYPERHOMOCYSTEINEMIA Pregnancy and postpartum determinants
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Health Determinants in Association with Cancer Mortality from a Health Ecological Perspective
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作者 Chenran Wang Zilin Luo +9 位作者 Jiaxin Xie Xiaolu Chen Yadi Zheng Zeming Guo Xiaoyue Shi Xinyue Zhu Wei Cao Fei Wang Xuesi Dong Ni Li 《Biomedical and Environmental Sciences》 2025年第12期1470-1481,共12页
Objective To explore the health determinants of all-cancer mortality from a health-ecological perspective.Methods Using the health-ecological model,we identified 15 health determinants across five domains:personal inn... Objective To explore the health determinants of all-cancer mortality from a health-ecological perspective.Methods Using the health-ecological model,we identified 15 health determinants across five domains:personal innate,behavioral,interpersonal network,socioeconomic,and macroenvironmental characteristics.Data on cancer outcomes and health determinants from 185 countries,classified using the Human Development Index(HDI),were extracted from GLOBOCAN 2022,the World Health Organization Global Health Observatory,the Global Burden of Disease Study 2021,the United Nations,and the World Bank.A multivariate linear regression model was used to estimate the association between health determinants and cancer outcomes.Results A total of 153 countries with complete information on cancer outcomes and health determinants were enrolled in the study.A higher all-cancer age-standardized mortality rate(ASMR)was associated with current tobacco use,alcohol consumption,obesity,agricultural employment,and lag-distributed income.In women aged 15–49 years,being married or in a union was associated with a lower ASMR.Early-onset ASMR was positively associated with agricultural employment,lag-distributed income,and unsafe sanitation.Notable sex differences were observed,although tobacco use and obesity were identified as risk factors in both sexes.Conclusion We underscore the crucial need to incorporate cross-sectoral interventions within a resilient healthcare system to effectively mitigate the cancer mortality burden. 展开更多
关键词 Health determinants Cancer mortality Health ecological model Dominance analysis
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Determinants of generalized anxiety and construction of a predictive model in patients with chronic obstructive pulmonary disease
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作者 Yi-Pu Zhao Wei-Hua Liu Qun-Cheng Zhang 《World Journal of Psychiatry》 2025年第2期48-58,共11页
BACKGROUND Patients with chronic obstructive pulmonary disease(COPD)frequently experience exacerbations requiring multiple hospitalizations over prolonged disease courses,which predispose them to generalized anxiety d... BACKGROUND Patients with chronic obstructive pulmonary disease(COPD)frequently experience exacerbations requiring multiple hospitalizations over prolonged disease courses,which predispose them to generalized anxiety disorder(GAD).This comorbidity exacerbates breathing difficulties,activity limitations,and social isolation.While previous studies predominantly employed the GAD 7-item scale for screening,this approach is somewhat subjective.The current literature on predictive models for GAD risk in patients with COPD is limited.AIM To construct and validate a GAD risk prediction model to aid healthcare professionals in preventing the onset of GAD.METHODS This retrospective analysis encompassed patients with COPD treated at our institution from July 2021 to February 2024.The patients were categorized into a modeling(MO)group and a validation(VA)group in a 7:3 ratio on the basis of the occurrence of GAD.Univariate and multivariate logistic regression analyses were utilized to construct the risk prediction model,which was visualized using forest plots.The model’s performance was evaluated using Hosmer-Lemeshow(H-L)goodness-of-fit test and receiver operating characteristic(ROC)curve analysis.RESULTS A total of 271 subjects were included,with 190 in the MO group and 81 in the VA group.GAD was identified in 67 patients with COPD,resulting in a prevalence rate of 24.72%(67/271),with 49 cases(18.08%)in the MO group and 18 cases(22.22%)in the VA group.Significant differences were observed between patients with and without GAD in terms of educational level,average household income,smoking history,smoking index,number of exacerbations in the past year,cardiovascular comorbidities,disease knowledge,and personality traits(P<0.05).Multivariate logistic regression analysis revealed that lower education levels,household income<3000 China yuan,smoking history,smoking index≥400 cigarettes/year,≥two exacerbations in the past year,cardiovascular comorbidities,complete lack of disease information,and introverted personality were significant risk factors for GAD in the MO group(P<0.05).ROC analysis indicated that the area under the curve for predicting GAD in the MO and VA groups was 0.978 and 0.960.The H-L test yieldedχ^(2) values of 6.511 and 5.179,with P=0.275 and 0.274.Calibration curves demonstrated good agreement between predicted and actual GAD occurrence risks.CONCLUSION The developed predictive model includes eight independent risk factors:Educational level,household income,smoking history,smoking index,number of exacerbations in the past year,presence of cardiovascular comorbidities,level of disease knowledge,and personality traits.This model effectively predicts the onset of GAD in patients with COPD,enabling early identification of high-risk individuals and providing a basis for early preventive interventions by nursing staff. 展开更多
关键词 Chronic obstructive pulmonary disease Generalized anxiety disorder Predictive model determinants analysis Forest plot
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Impact of Social Determinants on Vector-Borne Parasitic Diseases in Chad: A Case Study of Grand-Sido and Kouh-Est
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作者 Mahamat Alhadj Moussa Ibrahim Abdelsalam Hassan Gogo +5 位作者 Hassane Mahamat Hassane Petra Berger Djoukzoumka Signaboubo Aly Savadogo Abdelsalam Tidjani Soerge Kelm 《Open Journal of Applied Sciences》 2025年第1期110-126,共17页
Background: Social determinants of health (SDOH) significantly influence diseases with environmental components, like vector-borne parasitic diseases. This study aims to examine how these factors influence vector-born... Background: Social determinants of health (SDOH) significantly influence diseases with environmental components, like vector-borne parasitic diseases. This study aims to examine how these factors influence vector-borne parasitic diseases (VBPDs) transmission in Chad and provide recommendations for policy improvements. Methods: The study adopts the WHO Conceptual Framework of SDOH to compare two regions in Southern Chad: Kouh-Est, which has an ongoing vector control program, and Grand-Sido, which lacks such a program. The study includes both nomadic and sedentary populations to provide a comprehensive understanding of the SDOH influencing VBPDs. Households were randomly selected. Data on sociodemographic characteristics, literacy, knowledge of VBPDs and protective measures, and access to education and health facilities were collected. Results: A total of 202 households from 17 villages, including 820 participants, were surveyed. Agriculture, livestock, and fishing were the main occupations, involving 84.1% of participants. Literacy was low, with 36.7% non-educated, 47.7% completing primary school, 14.5% secondary school, and only 0.3% reaching tertiary education. Most villages lacked schools beyond the primary level, and nomadic populations were significantly less educated than sedentary ones (p Conclusion: Educational deficiencies, lack of protective measures against vectors, inadequate healthcare resources, and lifestyle conditions aggravated by poor road infrastructure, limited transportation, and economic constraints contribute to worsened VBPDs outcomes in these rural populations. Addressing these systemic issues in the surveyed communities is essential for improving health equity and VBPDs outcomes in these regions specifically and in similar populations settings more broadly. 展开更多
关键词 Social determinants of Health Vector-Borne Parasitic Diseases CHAD
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Glycemic control and determinants among type 2 diabetes mellitus in a regional hospital in South West Region,Cameroon
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作者 Chugbe N Sawah Ebot W Ojong +1 位作者 Njeodo N Vigny Moses N Ngemenya 《World Journal of Diabetes》 2025年第12期88-98,共11页
BACKGROUND The global prevalence of diabetes among adults aged 29-79 years was found to be 10.5%.It is a global public health threat with a rising trend in morbidity and mortality.Poor glycemic control(GC)among patien... BACKGROUND The global prevalence of diabetes among adults aged 29-79 years was found to be 10.5%.It is a global public health threat with a rising trend in morbidity and mortality.Poor glycemic control(GC)among patients with type 2 diabetes mellitus(T2DM)is a major determinant of diabetes-related complications.There are limited data on GC and associated factors among patients with T2DM in South West Region,Cameroon.AIM To assess GC and identify contributing factors among patients with T2DM in a regional hospital in South West Region,Cameroon.METHODS A cross-sectional study was conducted from February 2022 to July 2022 among 131 participants in Limbe Regional Hospital who were selected by convenience.Glycated hemoglobin(HbA1c)was measured by ion-exchange chromatography.Sociodemographic,clinical,and lifestyle data were collected,entered into Excel,and exported to Statistical Package for Social Sciences version 22 for analysis.A multivariate logistic regression analysis was conducted to assess the association between explanatory variables and GC.The level of significance was set at P<0.05.RESULTS The mean age was 56±5.1 years.Eighty-eight(67.2%)patients were female.The mean HbA1c was 8.8%±1.8%.Poor GC(HbA1c≥7%)was registered in 106(80.9%;95%confidence interval:73.1%-87.3%)participants.Lack of self-monitoring of blood glucose at home was associated with poor GC(adjusted odds ratio:3.858,95%confidence interval:1.262-11.800;P=0.018).CONCLUSION The majority of patients with T2DM had poor GC.Absence of self-monitoring of blood glucose at home was the main contributing factor for poor GC. 展开更多
关键词 Glycemic control determinants Type 2 diabetes mellitus Regional hospital South West Region Cameroon
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Theories and Determinants of IPO Underpricing:A Comprehensive Review
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作者 Zeshan Huang 《Proceedings of Business and Economic Studies》 2025年第2期267-273,共7页
IPO underpricing,the tendency for newly issued shares to trade above their offer price on the first day,is a persistent global phenomenon.Empirical evidence suggests that U.S.IPOs averaged an 18.8%first-day return fro... IPO underpricing,the tendency for newly issued shares to trade above their offer price on the first day,is a persistent global phenomenon.Empirical evidence suggests that U.S.IPOs averaged an 18.8%first-day return from 1980 to 2001,imposing significant indirect costs on issuers.This paper reviews key explanations for underpricing,including information asymmetry,signaling,agency conflicts,and behavioral factors.Empirical research highlights firm characteristics,underwriter reputation,market conditions,and regulatory factors as major determinants.While underpricing facilitates liquidity and market participation,it also reflects inefficiencies.This study synthesizes theoretical perspectives and empirical findings,emphasizing the need for improved disclosure,governance,and regulatory oversight. 展开更多
关键词 IPO underpricing Theoretical explanations Empirical determinants
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Association of social determinants of health and cardiovascular complications in type 2 diabetes in Colombia
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作者 Oswaldo Rincon Catalina Uscategui +4 位作者 Pedro Mancera Maria Luna Alba Rodriguez Mauricio Alvarez Isaac Guzman 《World Journal of Diabetes》 2025年第8期84-92,共9页
BACKGROUND Social determinants of health are social and economic factors that influence health intervention outcomes.Type 2 diabetes is a highly prevalent disease,primarily affecting individuals in low-to-middle-incom... BACKGROUND Social determinants of health are social and economic factors that influence health intervention outcomes.Type 2 diabetes is a highly prevalent disease,primarily affecting individuals in low-to-middle-income countries.However,the association between social determinants and cardiovascular complications in type 2 diabetes has not been widely studied.AIM To examine the relationship between social determinants of health and cardiovascular complications in individuals with type 2 diabetes.METHODS We conducted a retrospective cohort study with an analytical component at a national-level referral hospital for military personnel in Bogota,Colombia.Patients treated at the diabetes clinic between September 2021 and December 2022 who met the inclusion criteria were included.A total of 583 patients participated in the study.We performed descriptive,bivariate,and binary logistic regression analyses,adjusting for confounding variables.RESULTS Among the 583 patients included,urban residency[odds ratio(OR)=3.05,95%confidence interval(CI):1.01-9.20]and a middle or high educational level(OR=2.33,95%CI:1.14-4.72)were associated with an increased risk of coronary artery disease.Additionally,receiving diabetes education beyond that provided by the clinic(OR=2.15,95%CI:1.14-4.05)and lack of access to spaces for physical activity(OR=4.05,95%CI:1.31-12.5)were associated with a higher risk of diabetic nephropathy and cerebrovascular disease,respectively.CONCLUSION Programs for diabetes management should account for social determinants of health that contribute to cardiovascular complications and increased healthcare costs.Population-based studies are needed to guide targeted interventions and clarify causal relationships. 展开更多
关键词 Social determinants of health Type 2 diabetes mellitus Complications of diabetes mellitus POVERTY Educational status Urban population
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Asymptotic Behaviors of Hankel Determinants Whose Entries Involve Regularly- or Rapidly-Varying Functions. Part II*
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作者 Antonio Granata 《Advances in Pure Mathematics》 2025年第2期119-144,共26页
Here we complete our work on the asymptotics of Hankel determinants studying the case wherein the entries are “ultrarapidly”-varying functions in the sense that their logarithms are rapidly varying. Moreover, the la... Here we complete our work on the asymptotics of Hankel determinants studying the case wherein the entries are “ultrarapidly”-varying functions in the sense that their logarithms are rapidly varying. Moreover, the last results in the paper highlight analogies between algebraic identities for Hankelians with special entries and asymptotic relations valid for large classes of entries. 展开更多
关键词 Asymptotic Behaviors of Hankel determinants Asymptotic Expansions in the Real Domain Regularly- Rapidly- and Exponentially-Varying Functions of Higher Order Algebraic Identities for Hankelians
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Social determinants of health and retinal detachments
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作者 Michael B.Green Steven Ness 《Annals of Eye Science》 2025年第1期26-29,共4页
Rhegmatogenous retinal detachment(RRD)is a sight threatening condition in which the neurosensory retina separates from the underlying retinal pigment epithelium.With an incidence of 6.3 to 17.9 per 100,000 persons(1),... Rhegmatogenous retinal detachment(RRD)is a sight threatening condition in which the neurosensory retina separates from the underlying retinal pigment epithelium.With an incidence of 6.3 to 17.9 per 100,000 persons(1),RRD is a condition frequently encountered by vitreoretinal specialists.Because the fovea is responsible for central visual acuity,foveal detachment is associated with poor presenting vision and is the strongest prognostic factor predicting poor visual outcome after RRD repair(2). 展开更多
关键词 Retinal detachment social determinants of health(SDOH) public health
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不同发病程度黄萎病棉田病原菌致病力、数量和类型分析
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作者 冯自力 王宝全 +5 位作者 周京龙 魏锋 赵丽红 张亚林 冯鸿杰 朱荷琴 《植物保护》 北大核心 2026年第1期282-287,311,共7页
为明确我国不同棉区棉花黄萎病的病原菌种群特征,本研究于黄萎病发生高峰期在我国不同棉区选取黄萎病发病程度不同的棉田调查黄萎病发生情况,并取发病棉秆和田间土样,测定病原菌致病力、类型和土壤中微菌核数量。结果表明,黄萎病发病较... 为明确我国不同棉区棉花黄萎病的病原菌种群特征,本研究于黄萎病发生高峰期在我国不同棉区选取黄萎病发病程度不同的棉田调查黄萎病发生情况,并取发病棉秆和田间土样,测定病原菌致病力、类型和土壤中微菌核数量。结果表明,黄萎病发病较重棉田中强致病力菌株占27.0%,为发病较轻棉田的5.4倍;发病较重棉田土壤中微菌核数量显著高于发病较轻棉田,为发病较轻棉田的3.3~17.3倍。因此,棉田黄萎病菌数量急剧增加,以及病原菌的致病力增强,是导致棉田黄萎病发生加重的关键因素。 展开更多
关键词 棉花黄萎病 致病力测定 落叶型菌系 微菌核
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分散液液微萃取-高效液相色谱法测定固发洗剂中7种活性成分含量
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作者 谢寒 明荷 +2 位作者 张薇 方应权 汪方林 《中国药业》 2026年第5期100-104,共5页
目的建立同时测定固发洗剂中7种成分含量的分散液液微萃取-高效液相色谱(DLLME-HPLC)法。方法采用超声辅助的DLLME法对样品进行前处理,萃取剂选择50µL四氯甲烷,分散剂选择0.8 mL乙腈,加氯化钠使溶液浓度为2.5%(V/V)。采用HPLC法测... 目的建立同时测定固发洗剂中7种成分含量的分散液液微萃取-高效液相色谱(DLLME-HPLC)法。方法采用超声辅助的DLLME法对样品进行前处理,萃取剂选择50µL四氯甲烷,分散剂选择0.8 mL乙腈,加氯化钠使溶液浓度为2.5%(V/V)。采用HPLC法测定含量,色谱柱为Diamonsil C_(18)(2)柱(250 mm×4.6 mm,5µm),流动相为甲醇-0.1%甲酸溶液(梯度洗脱),流速为1.0 mL/min,检测波长分别为321 nm(阿魏酸)、355 nm(槲皮苷和槲皮素)、270 nm(藁本内酯和牛蒡子苷)、434 nm(大黄素和大黄素甲醚),柱温为30℃,进样量为10 mL。结果固发洗剂中阿魏酸、槲皮苷、槲皮素、藁本内酯、牛蒡子苷、大黄素、大黄素甲醚在各自质量浓度范围内与其峰面积线性关系均良好(r≥0.9995,n=5);精密度、稳定性、重复性试验结果的RSD均小于4.0%(n=6);平均加样回收率分别为97.59%,100.67%,103.79%,97.80%,98.78%,99.93%,99.63%,RSD分别为1.79%,4.42%,2.71%,1.53%,3.63%,3.25%,3.38%(n=6)。固发洗剂中上述7种成分的平均含量分别为26.36,33.10,38.95,37.25,25.51,61.12,23.21 mg/mL(n=3)。结论所建立的方法操作简便,重复性和稳定性均良好,结果准确,可用于同时测定固发洗剂中7种成分的含量。 展开更多
关键词 固发洗剂 分散液液微萃取法 高效液相色谱法 含量测定
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关井求压方法在特深井井控中的适用性
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作者 孙宝江 毕韶琨 +3 位作者 高永海 李昊 胡泽彪 张绪亮 《中国石油大学学报(自然科学版)》 北大核心 2026年第1期112-124,共13页
特深井钻井具有储层高温高压、井筒容积大、裸眼段穿越多个压力体系等特征,导致其关井求压过程中的井口压力演变规律与对地层压力反馈能力较常规井存在显著差异。为评估现有关井求压方法在特深井条件适用性,基于Sundrilling井控模拟软件... 特深井钻井具有储层高温高压、井筒容积大、裸眼段穿越多个压力体系等特征,导致其关井求压过程中的井口压力演变规律与对地层压力反馈能力较常规井存在显著差异。为评估现有关井求压方法在特深井条件适用性,基于Sundrilling井控模拟软件,以塔里木某特深井为例,模拟分析碎屑岩及碳酸盐岩储层条件下,循环法和憋压法求取关井压力过程中井筒压力响应关系及求压计算精度。结果表明:循环法求取关井立压在特深井中适用性较好,但在侵入流体进入井筒中浅部后可靠性下降;由于大容积井筒存在明显压力传递滞后,憋压法易导致计算的关井立压无法真实反映地层-井筒欠平衡压差;碳酸盐岩储层中,憋压致使钻井液向地层漏失,套压与立压增长不同步,故计算所得关井立压不能有效反映地层压力。针对上述问题,提出两项修正方法:一是建立憋压法流体压缩性修正,通过识别套压滞后阶段与趋势线获取有效套压增长量;二是提出憋压-节流循环联合求压方法,通过测定漏失量并构建漏失修正系数,以修正真实关井立压。利用现场关井求压数据验证,修正后的地层压力为76.66 MPa,符合根据钻柱液柱变化所推测结果。 展开更多
关键词 特深井 井控 关井求压 适用性评估 工艺优化
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液质联用色谱法测定化妆品中奎宁的含量
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作者 王珵 冯燕萍 张立雯 《广州化工》 2026年第2期105-107,共3页
采用高效液相色谱-三重四级杆质谱联用仪检测化妆品中奎宁的含量。样品经甲醇超声提取,以水-甲醇作为流动相,梯度洗脱,流速为0.3 mL·min^(-1)。采用正离子模式电喷雾电离(ESI+),多反应监测(MRM)模式检测,以待测组分相对离子峰面积... 采用高效液相色谱-三重四级杆质谱联用仪检测化妆品中奎宁的含量。样品经甲醇超声提取,以水-甲醇作为流动相,梯度洗脱,流速为0.3 mL·min^(-1)。采用正离子模式电喷雾电离(ESI+),多反应监测(MRM)模式检测,以待测组分相对离子峰面积定量,以标准曲线法计算含量。奎宁在0.818 8~40.94 ng·mL^(-1)时,与峰面积呈现良好的线性关系(r=0.9999),检测限为1.333μg·g^(-1),在洗发类和驻留型护发类基质中的平均回收率分别为82.41%和100.78%。市场随机抽取洗发类和驻留型护发类化妆品均单次进样即可快速完成样品分析。该检测方法具有定性、定量准确且灵敏、快捷的特点,可用于洗发类和驻留型护发类化妆品中奎宁的测定。 展开更多
关键词 奎宁 液质联用法 化妆品 分析方法
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银翘汤HPLC指纹图谱研究、化学模式识别及含量测定
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作者 隋欣蕙 靳彤 +3 位作者 邵丰德 门操 王栋 赵春杰 《沈阳药科大学学报》 2026年第2期172-183,198,共13页
目的基于高效液相色谱法建立10批银翘汤指纹图谱,结合化学识别评价其质量,并同时测定银翘汤中没食子酸甲酯、绿原酸、葛根素、升麻素、甘草酸铵5种成分的含量。方法分析采用Spherisorb ODS-2 C_(18)色谱柱(250 mm×4.0 mm,5μm);流... 目的基于高效液相色谱法建立10批银翘汤指纹图谱,结合化学识别评价其质量,并同时测定银翘汤中没食子酸甲酯、绿原酸、葛根素、升麻素、甘草酸铵5种成分的含量。方法分析采用Spherisorb ODS-2 C_(18)色谱柱(250 mm×4.0 mm,5μm);流动相为0.1%磷酸水(A)-乙腈(B)溶液,梯度洗脱;柱温为35℃;检测波长为254 nm;流速为1.0 mL·min^(-1)。使用“中药色谱指纹图谱相似度评价系统”、SPSS 19.0、SIMCA 13.0等软件建立指纹图谱、评价相似度并进行多元统计分析;通过外标法计算没食子酸甲酯、绿原酸、葛根素、升麻素、甘草酸铵5种成分的含量。结果在254 nm下,标定出26个共有峰,指认出5个色谱峰,相似度范围为0.997~0.999;化学模式识别结果表明,10批银翘汤可分为2类,质量最高的批次为S9,并筛选出9个差异性标志物。没食子酸甲酯、绿原酸、葛根素、升麻素、甘草酸铵分别在各自范围内呈良好线性关系(r均大于0.9998),回收率范围为95.6%~100.8%,RSD为0.8%~1.7%,10批银翘汤中5种成分的含量分别为13.805~20.032 mg·L^(-1)、108.345~114.386 mg·L^(-1)、16.929~19.389 mg·L^(-1)、9.646~13.394 mg·L^(-1)、29.208~31.654 mg·L^(-1)。结论建立的HPLC银翘汤指纹图谱及多成分含量测定分析方法稳定、简单、可靠,同时结合化学模式识别分析,可为银翘汤的质量控制提供参考。 展开更多
关键词 银翘汤 中药指纹图谱 含量测定 化学模式识别
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论数字伦理的法律之治
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作者 彭诚信 《上海大学学报(社会科学版)》 北大核心 2026年第1期1-14,共14页
线下社会与数字社会的基本价值取向具有一致性,数字社会中的伦理风险在根本上是因违背尊重人格平等与自由的普适性伦理所致。若忽视基本伦理的指导作用,数字法学将缺乏正当性根基;若无法律制度的保障,数字伦理也无法得到落实。基于人格... 线下社会与数字社会的基本价值取向具有一致性,数字社会中的伦理风险在根本上是因违背尊重人格平等与自由的普适性伦理所致。若忽视基本伦理的指导作用,数字法学将缺乏正当性根基;若无法律制度的保障,数字伦理也无法得到落实。基于人格与财产的不可通约性,个人信息财产价值如何正当外化构成数据确权的前提。在此前提下,数据不能迷信事前明确权利归属的理想状态,应以尊重数据处理者劳动贡献,提升数据利用效率,兼顾数据利益分配正义为综合考量,建立更加精细的数据确权制度。为规制数字技术应用的风险,应将“向善”纳入立法目的,确保数字技术应用的手段“可信”,即开发者或应用者对算法及可能对相关主体权益造成的影响进行公开并作出解释。数字社会伦理依然以自然人类为根基,数字伦理的法律之治则在于培育人的趋善能力。 展开更多
关键词 数字伦理 数字法理 数据确权 数字技术应用
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8,8′-亚甲基双射干苷元磺酸钠滴眼液的含量测定及有关物质的初步研究
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作者 陈帅 罗森 +5 位作者 汤依娜 罗恒 宁楠 赖明华 张磊 袁崇均 《华西药学杂志》 北大核心 2026年第1期88-92,共5页
目的建立8,8′-亚甲基双射干苷元磺酸钠(BXYW)滴眼液含量测定和有关物质限量的检测方法,并对有关物质进行初步研究。方法采用HPLC法检测BXYW滴眼液中BXYW的含量和有关物质限量,并采用超高效液相色谱-四级杆-飞行时间串联质谱法分析和推... 目的建立8,8′-亚甲基双射干苷元磺酸钠(BXYW)滴眼液含量测定和有关物质限量的检测方法,并对有关物质进行初步研究。方法采用HPLC法检测BXYW滴眼液中BXYW的含量和有关物质限量,并采用超高效液相色谱-四级杆-飞行时间串联质谱法分析和推导其有关物质的结构。结果含量测定方法的精密度、稳定性、重复性良好;平均加样回收率为99.70%,RSD=0.84%(n=6)。3批样品的含量分别为标示量的98.58%、98.34%、98.42%,有关物质的含量均低于2.0%,符合规定。质谱检测显示:BXYW滴眼液中的4个有关物质,均为BXYW异构或裂解而来。结论所用含量测定方法简便、快捷,可用于BXYW滴眼液的质量控制;有关物质的研究为药物的进一步研发奠定了基础,同时也为其他双黄酮化合物的合成提供了理论依据和解析思路。 展开更多
关键词 射干苷 8 8′-亚甲基射干苷元磺酸钠 滴眼液 含量测定 超高效液相色谱-四级杆-飞行时间串联质谱 双黄酮 有关物质
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高职院校学生绿色低碳行为影响因素研究
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作者 张永兰 王友保 +1 位作者 王文彦 方金生 《科教文汇》 2026年第5期138-142,共5页
本文从计划行为理论与“价值—规范—信念”理论出发,研究高职院校学生绿色低碳行为的影响因素,为完善绿色低碳教育体系提供依据。本文整合理论影响因素,提取教育、信念与态度、环境三个因子,并采用结构方程模型分析各因素的作用路径。... 本文从计划行为理论与“价值—规范—信念”理论出发,研究高职院校学生绿色低碳行为的影响因素,为完善绿色低碳教育体系提供依据。本文整合理论影响因素,提取教育、信念与态度、环境三个因子,并采用结构方程模型分析各因素的作用路径。结果表明:教育、信念与态度、环境均对学生绿色低碳行为产生正向影响;教育通过信念与态度影响行为的中介效应显著;环境对行为的影响较少通过信念与态度传递。可得出结论,加强绿色低碳教育应着重提升学生的信念与态度,通过认知改变促进其行为转变;环境因素主要通过规范约束直接影响行为。 展开更多
关键词 绿色低碳 影响因素研究 计划行为理论 “价值—规范—信念”理论
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