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71.
Algal farms maintained by different species of territorial herbivorous damselfishes vary in size, algal biomass, and species composition. To determine the factors that affect the structure of these farms, we compared farming behavior and intensity between two sympatric damselfish species, Stegastes nigricans (Lacepède) and S. obreptus (Whitley), which maintain two different types of farms in the Okinawa Islands, southern Japan. By weeding of indigestible algae and prompt exclusion of herbivorous fishes and grazing sea urchins, S. nigricans manage relatively small farms largely dominated by one algal crop species, Polysiphonia sp. In contrast, by delayed exclusion of herbivores, S. obreptus maintain larger farms invaded by diverse indigestible algae, such as Chondria sp. and Padina sp. As a result of intensive management, S. nigricans attains a higher algal biomass per area than does S. obreptus. This study provides a new perspective, as it suggests that damselfishes practise both intensive and extensive farming. The former results in small and highly productive monoculture farms of one palatable alga, while the latter leads to large, species-rich, mixed-culture farms.  相似文献   
72.
Selenium (Se) is incorporated into selenoproteins as the 21st proteinogenic amino acid selenocysteine. Serum Se concentrations decline during critical illness and are indicative of poor prognosis. Serum Se is mainly contained in the hepatically derived selenoprotein P (SePP) which controls the expression of antioxidative selenoproteins. Here, we describe the development of an immunoluminometric sandwich assay that uses two polyclonal sheep antihuman SePP antibodies. After assessing the stability of the analyte, we determined SePP concentrations in samples from healthy individuals and patients with sepsis. The analytical detection limit was 0.016 mg SePP/L serum. The assay was linear on dilution. SePP was stable in serum at room temperature for at least 24 h and resistant to six freeze-thaw cycles. Median SePP concentration in healthy individuals was 3.04 mg SePP/L serum (25th–75th percentiles, 2.6–3.4 mg/L) which corresponded to 98.4 μg Se/L serum. The interlaboratory CV was <20% for SePP values >0.06 mg/L. There was no association with gender, but concentrations differed between young and older individuals. Median SePP concentrations were significantly (P<0.0001) decreased in patients with sepsis (n=60) compared to healthy controls (n=318). Since SePP contains the major fraction of serum Se, we conclude that downregulation of SePP biosynthesis or removal of circulating SePP from blood underlies the negative acute phase response of serum Se in critical illness.  相似文献   
73.
《Biochimie》2013,95(11):2177-2181
In septic shock patients, alterations of plasma phospholipid fatty acid profile have never been described. The purpose of this monocentric, non-interventional, observational prospective study was to describe this fatty acid profile in the early phase of septic shock in intensive care unit. Thirty-seven adult patients with septic shock were included after the first day of stay in intensive care unit, before any form of artificial nutritional support. Plasma phospholipid fatty acid composition was determined by gas chromatography. All biological data from patients with septic shock were compared with laboratory reference values. Patients presented hypocholesterolemia and hypertriglyceridemia. They had low concentrations of phospholipid fatty acids specifically n-6 and n-3 polyunsaturated fatty acids (PUFAs) with a high n-6/n-3 ratio. Plasma phospholipid PUFA concentrations were strongly correlated with cholesterolemia. PUFAs/SFAs (saturated fatty acids) and PUFAs/MUFAs (monounsaturated fatty acids) ratios were low because of low percentage of n-6 and n-3 PUFAs and high percentage of SFAs and MUFAs. Low levels of plasma long chain PUFAs (≥20 carbons) were significantly associated with mortality at 28th day. In conclusion, plasma phospholipid FA profile of septic patients is very characteristic, close to that of acute respiratory distress syndrome and mortality is associated with long chain PUFA decrease. This profile could be explained by numerous non-exclusive physio-pathological processes 1) an activation of hepatic de novo lipogenesis that could contribute to hepatic steatosis, 2) an elevated adipose tissue lipolysis, 3) an increased free radical attack of FA by oxidative stress, 4) an over-production of inflammatory lipid mediators.  相似文献   
74.
Melatonin, cortisol, heart rate, blood pressure, spontaneous motor activity, and body temperature follow stable circadian rhythms in healthy individuals. These circadian rhythms may be influenced or impaired by the loss of external zeitgebers during analgosedation, critical illness, continuous therapeutic intervention in the intensive care unit (ICU), and cerebral injury. This prospective, observational, clinical study examined 24 critically ill analgo‐sedated patients, 13 patients following surgery, trauma, or acute respiratory distress (ICU), and 11 patients with acute severe brain injury following trauma or cerebral hemorrhage (CCI). Blood samples for the determination of melatonin and cortisol were obtained from each patient at 2 h intervals for 24 h beginning at 18:00 h on day 1 and ending 16:00 h on day 2. Blood pressure, heart rate, body temperature, and spontaneous motor activity were monitored continuously. Level of sedation was assessed using the Ramsey Sedation Scale. The severity of illness was assessed using the APACHE‐II‐score. The time series data were analyzed by rhythm analysis with the Chronos‐Fit program, using partial Fourier series with up to six harmonics. The 24 h profiles of all parameters from both groups of patients were greatly disturbed/abolished compared to the well‐known rhythmic 24 h patterns in healthy controls. These rhythm disturbances were more pronounced in patients with brain injury. The results of this study provide evidence for a pronounced disturbance of the physiological temporal organization in ICU patients. The relative contribution of analgosedation and/or brain injury, however, is a point of future investigation.  相似文献   
75.
目的:探讨地特胰岛素联合门冬胰岛素与生物合成人胰岛素注射液R对2型糖尿病强化治疗的疗效.方法:回顾性分析近年来我院住院治疗的180例2型糖尿病患者的临床资料,随机分为两组,每组90例,观察组予门冬胰岛素联合地特胰岛素治疗,对照组予生物合成人胰岛素注射液R治疗,记录并分析两组治疗前后空腹血糖(FPG)、餐后2小时血糖(2h-PPG)、血糖达标时间、达标时胰岛素用量及低血糖发生情况.结果:观察组较对照组患者在治疗前后糖化血红蛋白值、空腹血糖值都有所降低,血糖达标时间(d),胰岛素日用量(U/kg*d)及低血糖发生率(次/人)都有所减少,疗前后Homa-IR有所降低,Homa-β及体重有所增加,两组患者在治疗后糖尿病并发症都有所好转,观察组较对照组改善情况更优,但无显著性差异;其中对照组较观察组在糖化血红蛋白值、空腹血糖值上的比较中无显著差异.结论:门冬胰岛素联合地特胰岛素较生物合成人胰岛素注射液R强化治疗2型糖尿病患者与疗效接近,但起效迅速,持续时间久,低血糖反应少,胰岛素用量低.  相似文献   
76.
目的:研究血管紧张素Ⅱ1型受体拮抗剂科素亚对长期大强度运动所致心脏纤维化的预防作用。方法:48只雄性Wistar大鼠随机分为4组:对照组,科素亚处理的对照组,运动组,运动+科素亚处理组。运动组大鼠给予16周大强度运动,科素亚处理的大鼠每天训练前口服科素亚每次(50毫克/公斤/天)。通过计算心系数和观察心脏的组织形态学评估和比较各组大鼠心脏肥大的程度,免疫印迹法检测和比较各组大鼠4个心腔内转化生长因子-β1、纤维连接蛋白1、基质金属蛋白酶-2、I型胶原蛋白和III型胶原蛋白的蛋白表达水平。结果:长期大强度运动可造成大鼠左心室心脏壁肥大和右心室胶原沉积,心房和右心室的主要纤维化生物标志物的蛋白表达水平显著增加。科素亚预处理能够减少主要纤维化生物标志物TGF-β1、FIBROECTIN-1、MMP-2、TIMP-1、COLLAGEN-I、COLLAGEN-III表达水平,但不能完全改变心脏重量与体重比值增大的状态。结论:科素亚可部分预防耐力运动训练所致的心脏纤维化,但不能彻底改善心脏肥大。  相似文献   
77.
ObjectiveTo determine the mortality and comorbidities associated of patients with dementia admitted to the Intensive Care Unit (ICU) on the hospitalization and at one year of follow-up.Materials and methodsA retrospective observational cohort study was carried out between 2012 and 2017 at the Hospital Italiano de San Justo, of patients who were admitted to the ICU, these were observed up to hospitalary death, out hospital death one year of hospitalization, the disenrollment from the institution's health plan or the end of the follow-up.ResultsA total of 163 patients were included for analysis. We recorded those 79 patients (48.47%) died one year after the hospitalization, of them 25 (15.34%) in ICU and 8 (4.91%) in general room. The most frequent causes of death were respiratory. The factors most associated with mortality were: orotracheal intubation (HR = 2.01; 95% CI: 1.11-3.65; P = .02), history of leukemia (HR = 8.55; 95% CI: 1.82-40.05; P  .05), elevated Charlson (HR = 1.16, 95% CI: 1.04-1.41; P = .05), and elevated APACHE II at admission (HR = 1.07; 95% CI: 1.03-1.11; P  .05).ConclusionsThe present study expresses the prognosis of patients with a diagnosis of dementia admitted to the ICU and that depends not only on their baseline neurological status but also on the severity at admission and comorbidities.  相似文献   
78.
摘要 目的:分析重症监护室(ICU)患者压力性损伤(PI)的危险因素并探讨Braden评分和经皮氧分压(TcPO2)对其的预测价值。方法:选取2019年12月~2021年12月我院ICU 45例发生PI患者为PI组,另选取ICU 45例未发生PI患者为非PI组,收集患者基线资料、Braden评分及TcPO2。比较两组患者基线资料和Braden评分、TcPO2,采用多因素Logistic回归模型分析ICU患者发生PI的危险因素,绘制受试者工作特征(ROC)曲线分析Braden评分与TcPO2对ICU患者PI发生风险的预测价值。结果:PI组年龄大于非PI组,机械通气比例和体温高于非PI组,住院时间长于非PI组,血清白蛋白、Braden评分、TcPO2低于非PI组(P<0.05)。多因素Logistic回归分析显示,年龄增长(OR=1.100,95%CI:1.003~1.206)、体温上升(OR=1.217,95%CI:1.014~1.460)、住院时间延长(OR=1.240,95%CI:1.049~1.467)、Braden评分下降(OR=1.950,95%CI:1.312~2.898)、TcPO2下降(OR=1.128,95%CI:1.053~1.209)为ICU患者发生PI的危险因素(P<0.05)。ROC曲线分析显示,Braden评分和TcPO2单独与联合预测ICU患者PI发生风险的曲线下面积(AUC)分别为0.785、0.794、0.898,Braden评分联合TcPO2预测ICU患者PI发生风险的AUC大于二者单独预测。结论:年龄增长、体温上升、住院时间延长、Braden评分下降、TcPO2下降是ICU患者发生PI的危险因素,Braden评分、TcPO2对ICU患者PI发生风险具有一定的预测价值,二者联合效能更佳。  相似文献   
79.
Previous research has demonstrated that consanguineous marriage is a vector for socioeconomic inheritance and for the maintenance of family structure and property. On the basis of reconstituted families from the Krummhörn, Ostfriesland in the 18th and 19th centuries, we examine statistical correlations between ascertained inbreeding coefficients (F) based on family trees and socioeconomic status as well as the intergenerational transmission of landholdings. Semiparametric copula/bivariate regression models with non-random sample selection were applied to estimate F and the proportion of medium (0.0625?>?F?≥?0.0156) or high consanguineous unions (F?≥?0.0625), respectively. Our estimates for F as well as for the proportion of medium (0.0625?>?F?≥?0.0156) or high consanguineous unions (F?≥?0.0625) are significantly higher among socioeconomically privileged large farmer families than among the landless portion of the population. At the same time, our analyses show that a high level of consanguinity is associated with an increased intergenerational transmission of landholdings through the patriline (but not the matriline). We discuss the reproductive consequences of consanguinity among large farmers in connection with local resource competition, intensive kinship, and potential in-law conflicts.  相似文献   
80.
目的了解滨州市人民医院重症监护病房(ICU)常见病原菌种类及分布,并分析其耐药性的变迁,为临床合理应用抗菌药物提供依据。方法对2011年1月1日至2013年12月31日我院ICU住院患者各类标本分离的病原菌进行培养,应用BD PhoenixTM-100全自动微生物鉴定仪鉴定细菌菌种,K-B法进行药敏试验检测,WHONET 5.6软件进行统计分析。结果 3年共收集3 449份标本,检出非重复病原菌1 802株,阳性分离率为52.25%,其中革兰阴性菌1 399株占77.64%,以鲍曼不动杆菌、铜绿假单胞菌、肺炎克雷伯菌为主;革兰阳性菌275株占15.26%,以葡萄球菌和肠球菌为主;真菌128株占7.10%,以白色假丝酵母菌为主。主要致病革兰阴性杆菌对亚胺培南和美罗培南敏感,而对替卡西林、头孢他啶及哌拉西林均耐药;革兰阳性菌对万古霉素、替考拉宁、呋喃妥因、利奈唑胺及氯霉素敏感,而对青霉素耐药率高达100.00%。鲍曼不动杆菌、大肠埃希菌、肺炎克雷伯菌的ESBLs检出率分别为81.47%、74.19%和56.26%。结论我院ICU病原菌以革兰阴性杆菌为主,对大多数常用抗生素的耐药率较高,应加强病原菌耐药性的监测,为临床医生合理应用抗菌药物提供依据。  相似文献   
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