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Healthcare Quality According to ICU Level of Care
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作者 Edyta Karpeta Karola Warzyszyńska +1 位作者 Piotr Małkowski Maciej Kosieradzki 《Health》 2023年第12期1352-1365,共14页
Introduction: Little is known about the quality of healthcare in intensive care units (ICUs) in Poland. Data on patients hospitalized in ICUs in Warsaw and the results of their treatment are scarce. This information, ... Introduction: Little is known about the quality of healthcare in intensive care units (ICUs) in Poland. Data on patients hospitalized in ICUs in Warsaw and the results of their treatment are scarce. This information, crucial for improving the quality of ICU healthcare services, is not collected routinely. Quality indicators are essential in the concept of holistic quality management. Implementation of these indicators in ICUs is a complex and time-consuming process. Systematic increase in demand for quality assessment tools that can reflect real conditions of the practices of ICUs, prompts the search for effective solutions. Methods: The study included 12,155 patients hospitalized in 16 ICUs of Warsaw hospitals (8 ICUs, n = 3293 of the first level of care, and 8 ICUs, n = 8862 of the second level) between 1<sup>st</sup> January 2017 and 31<sup>st</sup> December 2018. ICUs in pediatric and oncological hospitals were excluded from the study. Characteristics and demography of patients as well as the structure, treatment and human resources of the ICUs in Warsaw were analyzed. Length of stay, unexpected extubations, nosocomial infections, ICU readmissions and standardized mortality ratios (SMR) were retrieved from National Health Fund, Ministry of Health, and other public databases. Results: In primary level ICUs patients’ age (66.42 vs. 64.43 years;p = 0.005) and comorbidity rate (30.56% vs. 22.78%, p = 0.037) were higher when compared to ICUs of the second level of care. The crude mortality rate in ICUs in Warsaw was significantly higher than in other EU countries and differed between ICUs of the first and the second level (34.77% vs. 24.53%, respectively;p = 0.004). SMRs were however very low: 0.71 and 0.64 (ns), respectively. ICU readmission rate, unexpected extubations, central catheter related infections, and length of stay were identical in both groups. More patients were admitted to ICU form emergency department and/or discharged home in Level 1 ICUs (18.9% vs 12.9%, p Conclusions: There are no major differences in quality of care provided by Level 1 and Level 2 ICUs in Poland, although more rigorous adhesion to admission and discharge policies is needed. Implementation of the instruments for assessing quality of ICUs including benchmarking, self-assessment of departments and evaluation of changes resulting from audits according to the Deming cycle is of utmost importance. Standardization of quality measures and markers, communication, and cooperation in reporting and creation of ICU medical registers is necessary to improve the quality of healthcare. 展开更多
关键词 Healthcare Quality Intensive Care Unit Mortality Rate Standardized Mortality Rate Unexpected Extubation Nosocomial Infections READMISSION
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The Effects of Chronic Hypoxia on Thermoregulation and Metabolism in Phrynocephalus vlangalii 被引量:3
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作者 Weixin LI Shiwei LIANG +4 位作者 Huihui WANG Ying XIN Songsong LU Xiaolong TANG Qiang CHEN 《Asian Herpetological Research》 SCIE CSCD 2016年第2期103-111,共9页
Phrynocephalus vlangalii are widely distributed on Tibetan plateau spanning diverse altitudes and habitats. In the present study, P vlangalii were exposed to 8% oxygen concentration in a hypoxic chamber for 6 weeks. T... Phrynocephalus vlangalii are widely distributed on Tibetan plateau spanning diverse altitudes and habitats. In the present study, P vlangalii were exposed to 8% oxygen concentration in a hypoxic chamber for 6 weeks. Then the body temperature (Tb), standard metabolic rate (SMR), heart rate and metabolic enzyme activities of the lizards were measured at 20℃ and 30℃. The results indicated that hypoxia exposure decreased Tb, SMR and heart rate. Lactate dehydrogenase (LDH) activity of 8% 02 group became significant elevated in liver and skeletal muscle compared with control group at 20℃, but descended significantly in heart. Using electrophoresis we found that LDH contains five isozymes (LDH1, LDH2, LDH3, LDH4 and LDH5) and are expressed specifically in liver, skeletal muscle and heart. Citrate synthase (CS) activity in the liver also decreased at 20℃ and 30℃. No significant difference of CS activity was found between the two groups in skeletal muscle and heart. 展开更多
关键词 LIZARD HYPOXIA HYPOTHERMIA standard metabolic rate enzyme activity
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Burden of celiac disease in the Mediterranean area 被引量:2
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作者 Luigi Greco Laura Timpone +10 位作者 Abdelhak Abkari Mona Abu-Zekry Thomas Attard Faouzi Bouguerrà Paskal Cullufi Aydan Kansu Dusanka Micetic-Turk Zrinjka Miak Eleftheria Roma Raanan Shamir Selma Terzic 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第45期4971-4978,共8页
AIM: To estimate the burden of undiagnosed celiac disease (CD) in the Mediterranean area in terms of morbidity, mortality and health cost. METHODS: For statistics regarding the population of each country in the Medite... AIM: To estimate the burden of undiagnosed celiac disease (CD) in the Mediterranean area in terms of morbidity, mortality and health cost. METHODS: For statistics regarding the population of each country in the Mediterranean area, we accessed authoritative international sources (World Bank, World Health Organization and United Nations). The prevalence of CD was obtained for most countries from published reports. An overall prevalence rate of 1% cases/total population was finally estimated to represent the frequency of the disease in the area, since none of the available conf idence intervals of the reported rates significantly excluded this rate. The distribution of symptoms and complications was obtained from reliable reports in the same cohort. A standardized mortality rate of 1.8 was obtained from recent reports. Crude health cost was estimated for the years between symptoms and diagnosis for adults and children, and was standardized for purchasing power parity to account for the different economic prof iles amongst Mediterranean countries. RESULTS: In the next 10 years, the Mediterranean area will have about half a billion inhabitants, of which 120 million will be children. The projected number of CD diagnoses in 2020 is 5 million cases (1 million celiac children), with a relative increase of 11% compared to 2010. Based on the 2010 rate, there will be about 550 000 symptomatic adults and about 240 000 sick children: 85% of the symptomatic patients will suffer from gastrointestinal complaints, 40% are likely to have anemia, 30% will likely have osteopenia, 20% of children will have short stature, and 10% will have abnormal liver enzymes. The estimated standardized medical costs for symptomatic celiac patients during the delay between symptom onset and diagnosis (mean 6 years for adults, 2 years for children) will be about €4 billion (€387 million for children) over the next 10 years. A delay in diagnosis is expected to increase mortality: about 600 000 celiac patients will die in the next 10 years, with an excess of 44.4% vs age-and sexmatched controls. CONCLUSION: In the near future, the burden of CD will increase tremendously. Few Mediterranean countries are able to face this expanding epidemic alone. 展开更多
关键词 PEDIATRIC Celiac disease Short stature ANEMIA OSTEOPENIA Purchasing power parity Standardized mortality rate Mediterranean area
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The Relation of Standard Metabolic Rate to Water Temperature and Body Weight of Schlegels Black Rockfish(Sebastodes Fuscescens) 被引量:1
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作者 马志敏 孙耀 +1 位作者 张波 唐启升 《Marine Science Bulletin》 CAS 2004年第1期80-87,共8页
Standard metabolic rates of Schlegels black rockfish with different body weights are determined in laboratory by using the flow-through respirometer at 11.2 ℃, 14.7℃ , 18.0 ℃ and 23.6 ℃ . The results indicate that... Standard metabolic rates of Schlegels black rockfish with different body weights are determined in laboratory by using the flow-through respirometer at 11.2 ℃, 14.7℃ , 18.0 ℃ and 23.6 ℃ . The results indicate that the standard metabolic rates increase with the increase of body weight at different temperatures. Relationship between them could be described as Rs = a ln W b. The mean of standard metabolic rate is significantly different among groups, but the b values are not. The standard metabolic rates of amended standard body weights decrease with the increase of temperature, and the mean of standard metabolic rate is also significantly different among groups when the standard body weights are 48.6 g, 147.9 g, and 243.1 g. Relationship between them could be described as Rsw = m e-b/T. The relations of standard metabolic rate ( Rs ) or relative metabolic rate ( Rs ) to body weight and temperature yield the following equations: Rs = 1.160 W 0.752 e -9.494/ T and Rs’= 1.160 W 0.254 e -9.494/ T. 展开更多
关键词 Standard metabolic rates Body weight TEMPERATURE Schlegels black rockfish
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Landslide Hazard Zonation Mapping in Ghat Road Section of Kolli Hills, India 被引量:4
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作者 Siddan ANBAZHAGAN Veerappan RAMESH 《Journal of Mountain Science》 SCIE CSCD 2014年第5期1308-1325,共18页
Landslides are the most common natural disaster in hilly terrain which causes changes in landscape and damage to life and property. The main objective of the present study was to carry out landslide hazard zonation ma... Landslides are the most common natural disaster in hilly terrain which causes changes in landscape and damage to life and property. The main objective of the present study was to carry out landslide hazard zonation mapping on 1:50,000 scale along ghat road section of Kolli hills using a Landslide Hazard Evaluation Factor(LHEF) rating scheme. The landslide hazard zonation map has been prepared by overlaying the terrain evaluation maps with facet map of the study area. The terrain evaluation maps include lithology, structure, slope morphometry, relative relief, land use and land cover and hydrogeological condition. The LHEF rating scheme and the Total Estimated Hazard(TEHD) were calculated as per the Bureau of Indian Standard(BIS) guidelines(IS: 14496(Part-2) 1998) for the purpose of preparation of Landslide Hazard Zonation(LHZ) map in mountainous terrains. The correction due to triggering factors such as seismicity, rainfall and anthropogenic activities were also incorporated with Total Estimated Hazard to get final corrected TEHD. The landslide hazard zonation map was classified as the high, moderate and low hazard zones along the ghat road section based on corrected TEHD. 展开更多
关键词 Landslide hazard zonation(LHZ) Kolli Hills Mountainous terrain LHEF rating scheme Bureau of Indian Standard(BIS) TEHD
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Monetary Stability and Crisis Predictions Fallacies
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作者 Mario Pines 《Management Studies》 2020年第2期158-171,共14页
In present days,our instable financial markets,characterized by heavier growing monetary responsibilities,are delivering and enlarging ever growing central banks’functions.The financial stability applied standards ha... In present days,our instable financial markets,characterized by heavier growing monetary responsibilities,are delivering and enlarging ever growing central banks’functions.The financial stability applied standards have been creating contradictory results in the recent Great Recessions since the year 1987 up to the central banks model,after the 2008 last financial crisis,with major central banks as the FED and the CEB(Diamond,2007,pp.189-200)conflicting main operative areas,monetary and financial goals with unexpected results.We have been living a very difficult and dramatic period,which suggests a lot of reconsiderations about what the monetary policy means and may pursue and in which area,with respect to the financial system restrictions,in particular,during the post-second World War,based initially on the pseudo gold dollar parity,things were relatively stable and major financial crises were happening in emerging peripheral markets only.Financial stability was ever relevant,but it was not something to which governments devoted institutional attention.Based on what happened during the recent crisis,it is now of capital responsibility connecting monetary and economic financial stability jointly.Central banks,on the contrary,seem not able to pursue both functions relying on classical market tools.Up to now,the only obligation,imposed to a central bank as a private agent,has been taking care of monetary stability,to contain inflation rates over upper limits,assumed in entering definitely in the legal tender monetary,regime almost everywhere over the planet.Originally,for specific monetary policy purposes alone,between central banks and possible financial entities,there were no guidelines or structural determined controls,only institutional and statutory single bank’s operational clauses.There were no legal constraints such as formal loan to-value,or loan to cash-flows,or formal capital level limits,based on actual constraints.Free repurchase agreements and sales or purchases of securities(the most relevant tools of monetary policy guidelines),generally based on private financial covenants,were the sole most recurrent tactical interferences in adjusting the economic free activity.The assuming statutory thresholds were casual in the incorporating state,central banks used to monitor the activities of agents through economic incentives,rather than mandating and monitoring specific legal prescriptions.The evolving inconsistency of both activities has become even more manifest;two conditions should be fulfilled simultaneously:To avoid dilemmas in which a central bank might be called to make the autonomous independent management choice between monetary price stability,pursuing at same time,generally incompatible,financial stability,two different policies should be rarely jointly assigned to same bodies,especially central banks.As regards the first issue,the IMF nevertheless,with Brunnermeier and Sannikov(Brunnermeier&Sannikov,2012),has argued that price stability and financial stability are interlinked Short-term debt financing played an important role in the run-up to the financial crisis,as increases in leverage helped boost growth but also made the economy more susceptible to a downturn.Since the recession,private agents have reduced their debt level while many governments have increased borrowing.This deleveraging process appears to be holding back the recovery,and the Japanese experience suggests that such deleveraging can continue over an extended period”,unless in the long run we are all broken at state level,as history seems now to prove.It is true indeed,as reminded by Lamfalussy(Lamfalussy et al.,2010,pp.7-9),and now widely proved by facts,that prices and the growth-employment objectives,run into each other because it is seldom the case that the pursuit of one is consistent with the pursuit of the second in global economies. 展开更多
关键词 central banks monetary policy financial instability gold standard and exchange rates
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What Happened to Jacques Rueff and Robert Triffin?
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作者 Mario Pines 《Management Studies》 2022年第5期263-274,共12页
A present monetary theory of the Great Depression has been explained as stemming from Milton Friedman,ignoring the previous Davanzati,a Florentine finding,in the 16th Century,an explanation solution to the increase of... A present monetary theory of the Great Depression has been explained as stemming from Milton Friedman,ignoring the previous Davanzati,a Florentine finding,in the 16th Century,an explanation solution to the increase of prices due to the arrival of Spanish silver from the New World.Designed to counter the Keynesian notion that the Depression resulted from instability theories,characterizing most modern capitalistic economies,Friedmans explanation identified lately the monetary trend as a disordered monetary policy,carried out by erroneous Federal Reserve Board interventions,possible after the Aldrich-Vreeland innovations,introducing Treasury money in the year 1908.More recent works about the Great Depression reconsider the attempts to restore the international gold standard,suppressed on the brink of World War I.We learnt that current views of the Depression,as analyzed in the 1920s by Ralph Hawtrey and Gustav Cassel,while recommending a gold standard reset,reflect that such standard risk deflations,unless the resulting increase in the international monetary demand linked to physical gold,could be satisfied.Although their early warnings of potential disaster became actual and their policy advice was consistently correct,their contributions were ignored and forgotten.The vanishing of their comments was firstly outlined not a long time ago,by Batchelder and GlasnerWhat Ever Happened to Hawtrey and Cassel?(2013)This paper explores the possible reasons for the remarkable historical disregard of the Hawtrey-Cassel monetary explanation of the Great Depression,even by Nobel Prize winner Robert Mundell in his 2000 historical Nobel reconsideration of the monetary 20th century(Mundell,2000).The paper stresses the identical historical conditions surfacing after the Bretton Woods agreements.Robert Triffin and Jacques Rueff comment likely warnings as in the first Great Depression,under the monetary policy illusion and the Central Banks excessive disregard of the basics of the quantitative theory on the long run,mostly ignored.Robert Triffin started to address the problem in March and June of 1959,Italian Banca Nazionale del Lavoro Quarterly Review.The first of these articles(Part One:Diagnosis)explains in the simplest possible terms,the extraordinary success of the nineteenth century system of international gold based convertibility,and the calamitous collapse of the late 1920s attempts to bring it back to life.It may hold for us today an indication of the main efforts facing the similar attempt atreconstructing the pastexpressed some 64 years later,after the first of August 1914,by Triffin during the 1978 Christmas weekend.To deal with them in simple,commonsense terms would inevitably classify the author as an unrealistic whose views deserve no more than a raising of eyebrows.Jacques Rueff,with his The Monetary Sin of the West,a logical consequence of the Triffin previous notes of the 1960s,went straight to the consequences of the Camp David resolutions of President Nixon who just temporarily asked his Treasury Secretary,John Conally to suspend the gold convertibility.There were two changes in United States(U.S.)government policy toward the monetary role of gold in the last 100 years.The first was in 1933-1934;all holdings of gold were confiscated in March 1933.Then,the U.S.Treasury adopted a parity for the U.S.dollar of$35.00 an ounce at the end of January 1934.Gold production surged,the private demand for gold fell,and the U.S.experienced large increases in foreign demand for U.S.dollar securities.In those years there was a massive flow of gold to the U.S.The second historical change in U.S.gold policy followed the meeting at Camp David on August the 15th 1971,when the U.S.Treasury closed its gold window fearing a run on its gold holdings,declining towards$10 billion.Some U.S.officials sought to diminish the monetary role of gold.The anticipation of some U.S.officials attending Camp David was that the persistent U.S.payments problem would disappear,once foreign currencies had no parities in terms of the U.S.dollar.The prices of these foreign currencies would increase and the U.S.trade surplus would become larger.Instead,many foreign Central Banks became larger buyers of dollarssecurities,which led to a higher price of the U.S.dollar and a U.S.trade structural deficit.The U.S.international investment position morphed from the worlds largest creditor country,to the worlds present day largest debtor. 展开更多
关键词 Central Banks monetary policy financial instability gold standard and exchange rates
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Research on Effective Access for Strengthening and Improving the Management and Benefit use of Large Instruments
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作者 Cui Zhongxing, Hu Mingxing, Chen Cunli, Kang Wenxing, Hua XianghanXi’an University of Technology Xi’an, 710048, P.R.China 《International Journal of Plant Engineering and Management》 1998年第2期32-36,共5页
The purchasement and development as well as the benefit of utilization for the large equipment in universities of China are analyzed in this paper, the paper in dicates that in utilization of large equipment the contr... The purchasement and development as well as the benefit of utilization for the large equipment in universities of China are analyzed in this paper, the paper in dicates that in utilization of large equipment the contradictions such as urgency and necessity for the purchasement and development of large equipment and serious waste in resources since inadequacy of annual utilization rate of large equipment are existed, it also raises that the key step of giving full play to the benefit of large equipment is to strengthen management and development after the equipment are purchased, the paper regards through stressing standardized management and maintenance、opening the laboratory、improving the functions of equipment、renovating technology、fully examining and scientifically deciding before purchasement, the investment benefit for the large equipment can be raised effectively. 展开更多
关键词 large equipment standardized management improvement of functions investment benefit utilization rate
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A Novel Analysis Approach of Uniform Persistence for an Epidemic Model with Quarantine and Standard Incidence Rate
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作者 Song-bai GUO Yu-ling XUE +1 位作者 Xi-liang LI Zuo-huan ZHENG 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2024年第3期695-707,共13页
Inspired by the transmission characteristics of the coronavirus disease 2019(COVID-19),an epidemic model with quarantine and standard incidence rate is first developed,then a novel analysis approach is proposed for fi... Inspired by the transmission characteristics of the coronavirus disease 2019(COVID-19),an epidemic model with quarantine and standard incidence rate is first developed,then a novel analysis approach is proposed for finding the ultimate lower bound of the number of infected individuals,which means that the epidemic is uniformly persistent if the control reproduction number R_(c)>1.This approach can be applied to the related biomat hem at ical models,and some existing works can be improved by using that.In addition,the infection-free equilibrium V^(0)of the model is locally asymptotically stable(LAS)if R_(c)<1 and linearly stable if R_(c)=1;while V^(0)is unstable if R_(c)>1. 展开更多
关键词 uniform persistence epidemic model control reproduction number QUARANTINE standard incidence rate
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The effect of the fear factor on the dynamics of an eco-epidemiological system with standard incidence rate
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作者 Chunmei Zhang 《Infectious Disease Modelling》 CSCD 2024年第1期128-141,共14页
In order to protect endangered prey,ecologists suggest introducing parasites into predators which have achieved the expected goal in practice.Then how to explain the inherent mechanism and validate the effectiveness o... In order to protect endangered prey,ecologists suggest introducing parasites into predators which have achieved the expected goal in practice.Then how to explain the inherent mechanism and validate the effectiveness of this approach theoretically?In response to this question,we propose an eco-epidemiological system with the standard incidence rate and the anti-predator behavior in this paper,where the predator population is infected by parasites.We show the existence and local stability of equilibria for the system,and verify the occurrence of Hopf bifurcation.Theoretical and numerical results suggest that the fear effect reduces the density of the predator population but has no effect on the density of prey population.In addition,the cost of fear may not only break the stability of the equilibrium of the system,but also induce the equilibrium to change from unstable to stable.Based on the theoretical analysis,we confirm that introducing parasites into the predator population is an effective method to protect endangered prey. 展开更多
关键词 Eco-epidemiological system Fear factors Standard incidence rate Stability Bifurcation.2010 MSC 92A17
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Four-year dynamic observation and study on standardized management of elderly patients with type 2 diabetes in Beijing Yongding Road Community 被引量:4
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作者 Yue Li Dongyun Shen +10 位作者 Wei Zhang Yimin Wang Hongmei Li Jie Geng Liying Yang Zhijun Xiao Yan Liu Zhigang Feng Linying Cao Yan Jin Lixia Shi 《Family Medicine and Community Health》 2014年第2期22-29,共8页
Purpose:This study aimed to understand the joint standard of blood glucose,blood li-pids,and blood pressure in elderly patients>60 years of age with type 2 diabetes in the Beijing Yongding Road Community.Methods:On... Purpose:This study aimed to understand the joint standard of blood glucose,blood li-pids,and blood pressure in elderly patients>60 years of age with type 2 diabetes in the Beijing Yongding Road Community.Methods:One hundred ninety-two elderly patients>60 years of age who were diagnosed with type 2 diabetes in Yongding Road Community served as the investigation subjects,under-went standard management,and the dynamic changes in blood glucose,blood lipids,and blood pressure were monitored for 48 months.Results:At the end of the observation period,the standard rates of fasting blood glucose and postprandial blood glucose were 72.55%and 80.00%,respectively,which were increased compared with 55.73%and 56.08%at baseline(P<0.01).The standard rate of HbA1c was 59.81%,which was increased compared with 53.44%at baseline(P>0.05).The standard rates of TG and LDL-C were 76.71%and 60.38%,respectively,which were increased compared with 54.69%and 34.74%at base-line,and the standard rate of HDL-C was 13.64%,which was decreased compared with 40.10%at baseline(P<0.01).The standard rate of BP was 58.33%,which was increased compared with 38.54%at baseline(P<0.01).The optimal control rate of blood glucose for 48 months(the standard times of the total measurement times in 48 months≥75%)was higher;the fasting blood glucose was 52.17%,the 2-h postprandial blood glucose was 60.22%,and the HbA1c was 46.45%.The optimal control rate of blood lipids was lower;LDL-C was 17.49%and HDL-C was 13.59%.The optimal control rate of BP was 9.13%.At the end of the observation period,the levels of fasting blood glucose and postprandial blood glucose were decreased by 0.7 mmol/L and 1.48 mmol/L,respectively,compared with the base-line(P<0.01).The level of HbA1c was decreased by 0.18%compared with the baseline(P<0.05).The levels of LDL-C and HDL-C were decreased by 0.4 mmol/L and 0.23 mmol/L,respectively,compared with the baseline(P<0.01).The levels of SBP and DBP were decreased by 4 mmHg compared with the baseline(P<0.01).At the end of the observation period,the joint standard rate of the three indices of HbA1c,LDL-C,and BP was 24.72%,which was increased compared with 6.25%at baseline(P<0.01).Conclusion:Standardized management of elderly patients with diabetes in the Community can improve the joint standard rate of blood glucose,blood lipids,and blood pressure.The op-timal control rate and joint standard rate are the important indices for evaluating the quality of diabetes management. 展开更多
关键词 Type 2 diabetes mellitus COMMUNITY MANAGEMENT Joint standard rate
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Electrochemistry of CeCl3 in Molten LiCl-KCl Eutectic 被引量:1
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作者 ZHANG Meng HAN Wei +3 位作者 ZHANG Milin LI Yunna ZHU Fengyan XUE Yun 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2014年第3期489-494,共6页
The electrochemical properties of CeCl3, dissolved in LiCI-KCI eutectic melt, were investigated by electrochemical techniques, such as cyclic voltammetry and square wave voltammetry on Mo electrode. It was shown that... The electrochemical properties of CeCl3, dissolved in LiCI-KCI eutectic melt, were investigated by electrochemical techniques, such as cyclic voltammetry and square wave voltammetry on Mo electrode. It was shown that Ce(Ⅲ) is reduced to Ce(0) based on a three-step mechanism. In a temperature range of 833-923 K, the diffusion coefficient of Ce(Ⅲ) is lgDceoH)=-2.49-1704/T determined by means of the Berzins-Delahay equation with two different expressions under reversible and irreversible conditions. The apparent standard potential of a Ce(Ⅲ)/Ce(0) redox system is ECE^3+0^*/Ce^0 =3.551+0.0006132T(K) vs. Cl2/Cl^-. Some thermochemical properties of CeCl3 solutions were also derived from the electrochemical measurements, such as the enthalpy, entropy, Gibbs free energies and the activity coefficients of Ce(Ⅲ). The Gibbs free energy of a dilute solution of CeCl3 in this system was determined to be △G^0CeCl3/(kJ·mol^-1)=-1027.9+0.178T(K) And the activity coefficients, γCeCl3 , range between (7.78-9.14)×10^-3. Furthermore, the standard rate constant of kinetic reaction was calculated to be (4.94-9.72)× 10^-3 cmZ/s and the reaction was regarded as a quasi-reversible reaction under the present experimental conditions at 833 K. 展开更多
关键词 LiCl-KCl eutectic melt CECL3 Standard rate constant Standard apparent potential Activity coefficient
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Every breath you take:assessing metabolic costs of toxin resistance in garter snakes(Thamnophis)
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作者 Haley A.MONIZ Molly A.RICHARD +1 位作者 C.M.GIENGER Chris R.FELDMAN 《Integrative Zoology》 SCIE CSCD 2022年第4期567-580,共14页
Trait specialization often comes at the expense of original trait function,potentially causing evolutionary tradeoffs that may render specialist populations vulnerable to extinction.However,many specialized adaptation... Trait specialization often comes at the expense of original trait function,potentially causing evolutionary tradeoffs that may render specialist populations vulnerable to extinction.However,many specialized adaptations evolve repeatedly,suggesting selection favors specialization in specific environments.Some garter snake(Thamnophis)populations possess specialized mutations in voltage-gated sodium channels that allow them to consume Pacific newts(Taricha)defended by a highly potent neurotoxin(tetrodotoxin).These mutations,however,also decrease protein and muscle function,suggesting garter snakes may suffer evolutionary tradeoffs.We measured a key physiological process,standard metabolic rate(SMR),to investigate whether specialized adaptations in toxin-resistant garter snakes affect baseline energy expenditure.In snakes,skeletal muscles influence metabolism and power ventilation,so inefficiencies of sodium channels in these muscles might impact whole-animal energy expenditure.Further,because sodium channels are membrane-bound proteins,inefficiencies of channel kinetics and performance might be exacerbated at suboptimal temperatures.We measured SMR in 2 species,Thamnophis atratus and Thamnophis sirtalis,that independently evolved tetrodotoxin resistance through unique mutations,providing replicate experiments with distinct underlying genetics and potential physiological costs.Despite our expectations,neither resistance phenotype nor sodium channel genotype affected metabolism and resistant snakes did not perform worse under suboptimal body temperature.Instead,T.atratus and T.sirtalis show nearly identical rates of mass-adjusted energy expenditure at both temperatures,despite differing eco-morphologies,life histories,and distant phylogenetic positions.These findings suggest SMR may be a conserved feature of Thamnophis,and that any organismal tradeoffs may be compensated to retain whole-animal function. 展开更多
关键词 adaptation standard metabolic rate TETRODOTOXIN toxin-resistance TRADEOFF
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