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61.
目的:探讨不同剂量盐酸羟考酮复合右美托咪定对开腹手术患者镇痛效应及血流动力学的影响。方法:选择从2015年3月到2017年3月期间在我院接受开腹手术治疗的患者100例进行研究。根据随机数字表法对患者进行分组,A组(应用1.0 mg/kg的盐酸羟考酮及2.5μg/kg的右美托咪定麻醉)、B组(应用0.75 mg/kg的盐酸羟考酮及2.5μg/kg的右美托咪定麻醉)、C组(应用0.5 mg/kg的盐酸羟考酮及2.5μg/kg的右美托咪定麻醉)和D组(应用1.0 mg/kg的盐酸羟考酮麻醉),每组各25例。对比各组镇痛效应满意度以及麻醉诱导前(T0)、插管即刻(T1)、插管后5 min(T2)时的血流动力学指标,并统计各组不良反应情况。结果:A、B、C三组的镇痛效应满意度均分别明显高于D组,差异均有统计学意义(均P0.05),A、B、C三组的镇痛效应满意度对比差异无统计学意义(P0.05)。A、B组T1时的收缩压(SBP)、舒张压(DBP)、平均动脉压(MAP)及心率(HR)水平均分别高于C、D组,差异有统计学意义(P0.05);T0和T2时,各组的SBP、DBP、MAP及HR水平相比差异均无统计学意义(均P0.05)。各组T1时SBP、DBP、MAP及HR水平与T0时相比明显上升,而T2时又明显下降,差异均有统计学意义(P0.05)。B组不良反应总发生率为12.00%,明显低于A组的36.00%、C组的44.00%及D组的40.00%,差异均有统计学意义(均P0.05)。结论:不同剂量的盐酸羟考酮与右美托咪定复合麻醉对开腹手术患者的镇痛效应较好,并对患者的血流动力学水平均造成一定影响,但随着时间的延长而逐渐减弱,2.5μg/kg的右美托咪定以及0.75 mg/kg的盐酸羟考酮复合麻醉的安全性较高,值得在临床上推广应用。  相似文献   
62.
Aims The purpose of this study is to investigate the characteristics of nutrient cycling in Cunninghamia lanceolata plantations with different ages, and to provide scientific basis for the management of high-yield plantations in China. Methods In this study, we used the ecological data of the past 25 years in Hunan Huitong Ecological Station and analyzed the nutrient cycling characteristics of the C. lanceolata plantation forests with different ages according to the law of tree growth and the dynamics of nutrient uptake. Important findings For most nutrients, their concentrations ranked in order as leaf > twig > bark > root > stem for all C. lanceolata trees with any ages. When the tree age was less than 12 years, nutrient concentrations increased with age, while they decreased with age when the tree was more than 12 years old. The changes in average annual nutrient uptake with age showed two peaks. Nutrient return gradually increases with age. For the same age, the nutrient use efficiency followed the order of phosphorus (P) > potassium (K) > nitrogen (N) > magnesium (Mg) > calcium (Ca). After the stand was closed, the nutrient utilization efficiency increases with the growth and development of trees. The cycling intensity of Ca and Mg was greater than that of N and P at the same stand age. The changes in nutrient cycling intensity with age varying curve with stand age acted as parabolic curve. Utilization of N, P and K was longer than displayed a parabolic shape for all elements. The utilization time of each element got shorter with increasing stand age. These results suggested that the nutrient uptake in different growth stages was not only controlled by the quantity of biomass, but also affected by the difference in nutrient concentration between previous and current stages. The nutrient cycling processes were jointly controlled by the mechanisms of nutrient redistribution and storage in Cunninghamia lanceolata, during the growth and development stages, and the nutrient use efficiency during different growth stages. © 2018 Editorial Office of Chinese Journal of Plant Ecology. All rights reserved.  相似文献   
63.
  • A significant asynchronous phenomenon exists in super hybrid rice because of the differences in spike and spikelet positions, which affect the accumulation and properties of starch. However, little is known about the endosperm enrichment and physicochemical properties of starch in superior and inferior grains in super hybrid rice.
  • Rice YY2640 was selected as study material to investigate the enrichment and physicochemical properties of starch in superior and inferior grains in super rice using semi‐thin sections, X‐ray diffraction and related technologies.
  • Superior grain filling was a continuous process, whereas inferior grain only started 8–10 days after anthesis. The order of starch accumulation starts in the central endosperm, then in the endosperm of the proximal vascular bundle and finally in the aleurone layer. Compared with the inferior grains, the superior grains have a higher 1000‐grain weight, apparent amylose content, total starch content, average starch granule size, relative crystallinity, solubility and a resonance peak ratio at 1022/995 cm?1, whereas the swelling power and ratio of the resonance peak at 1045/1022 cm?1 were lower. The final degree of hydrolysis of HCl, AAG and PPA of the superior grains were significantly lower than those of the inferior grains.
  • The findings indicate that the different physicochemical properties of starch were mainly related to the development order of superior and inferior grains and the spatial enrichment of starch.
  相似文献   
64.
摘要 目的:探讨不同剂量右美托咪定辅助麻醉对老年结肠癌根治术患者麻醉效果,并分析术后谵妄的影响因素。方法:选取2019年4月~2021年1月期间我院收治的160例老年结肠癌根治术患者,根据随机数字表法将患者分为A组(53例)、B组(53例)和C组(54例)。A组和B组均于麻醉诱导前给予0.5 μg/kg右美托咪定,以0.2 μg/kg?h速率静脉输注至手术结束前30 min,A组术后镇痛时再给予右美托咪定0.05 μg/kg?h。C组给予等容量和等速率的生理盐水。观察三组的应激反应、麻醉效果、不良反应发生率、谵妄发生率。根据是否发生谵妄分为谵妄组(n=28)和无谵妄组(n=132)。采用Logistic回归分析术后谵妄的影响因素。结果:三组术后第3 d C反应蛋白(CRP)、白介素-6(IL-6)、多巴胺、肾上腺素均较手术结束升高(P<0.05)。A组、B组术后第3 d CRP、IL-6、多巴胺、肾上腺素低于C组(P<0.05)。A组、B组术后第3dCRP、IL-6、多巴胺、肾上腺素组间对比,无明显差异(P>0.05)。A组、B组、C组的不良反应总发生率组间的对比无明显差异(P>0.05)。B组的谵妄发生率明显低于A组、C组(P<0.05)。A组、C组谵妄发生率组间对比无明显差异(P>0.05)。单因素分析结果显示,术后谵妄的发生与年龄、术前抑郁、术前合并基础疾病数量、术中低氧血症、气腹后PaCO2、白蛋白有关(P<0.05)。多因素Logistic回归分析结果显示:术前抑郁、年龄≥70岁、术前合并基础疾病数量≥3、术中低氧血症、气腹后PaCO2偏高、白蛋白偏低是导致老年结肠癌根治术患者术后谵妄的危险因素(P<0.05)。结论:小剂量右美托咪定辅助麻醉可提高老年结肠癌根治术患者的麻醉效果,减少谵妄的发生率,同时术前抑郁、年龄≥70岁、术前合并基础疾病数量≥3、术中低氧血症、气腹后PaCO2偏高、白蛋白偏低是引起谵妄发生的危险因素。  相似文献   
65.
李霞  胡楠  赵启迪  黄健玲  李培骏  周玉恒 《广西植物》2019,39(11):1519-1526
该研究采用氢氧化钠-氯乙酸的化学反应体系制备羧甲基化肠浒苔多糖,以获得不同取代度的羧甲基化肠浒苔多糖,取代度的大小受氢氧化钠浓度、反应温度和反应时间的影响。结果表明:(1)当氢氧化钠浓度20%、反应温度60℃、反应时间3 h时,得到羧甲基化的最大取代度为0.781。(2)通过体外抗氧化来评价不同羧甲基化肠浒苔多糖的抗氧化活性。(3)当羧甲基化肠浒苔多糖的浓度为1.6 mg·mL~(-1)时,羧甲基化肠浒苔多糖清除羟基自由基、超氧阴离子自由基的能力分别为44.45%、51.98%,其清除DPPH自由基清除率和还原能力分别为16.75%、0.457 6。(4)与修饰前的相比,羟基自由基、超氧阴离子的清除能力均有较大幅度提高,羧甲基化修饰对肠浒苔多糖的DPPH自由基和还原力有减弱作用。以上结果表明,羧甲基化修饰引起的肠浒苔多糖的结构变化可以提高其抗氧化活性。  相似文献   
66.
Beneficial arthropods are often used for suppressing specific pest outbreaks in agricultural crop systems. The European earwig, Forficula auricularia L., (Dermaptera: Forficulidae), is an important natural enemy in fruit orchards. Recently, ecological studies were published describing earwig dispersal and survival during summer, hereby revealing clear differences between populations with a single brood (SBP) and two broods a year (DBP). In this article, we will describe three potential mortality factors of earwigs during the underground winter period, namely cold temperatures, parasitoids and soil tillage. This knowledge is essential for making efficient management strategies for increasing earwig abundance in fruit orchards. The effect of cold temperatures was checked during a 3‐year semi‐field experiment. Parasitism rates of Triarthria spp. (Fallén) and Ocytata pallipes (Fallén) (Diptera: Tachinidae) were obtained in a rearing experiment. The negative effect of soil tillage on the survival of earwigs nests was checked in a field experiment covering a 4‐year time period. A strong, negative relation between temperature [cooling day degrees (CDD)] and survival of female and male earwigs during winter was found. Male earwigs of SBP died very quickly, mimicking natural conditions. Between 60% and 90% of females do not survive winter. Survival of females in DBP was higher than in SBP. Parasitism rates vary a lot between species, generation, year and location (0–20%). During winter, we found a maximum mortality of 13%. There is a clear trend that soil tillage can reduce the number of nymphs in spring and summer by 50%. Implications for biocontrol are the following: (i) mortality owing to temperature can be predicted using CDD and if necessary preventive management actions can be undertaken to control pests; (ii) parasitism rates are negligible compared to high impact of temperature; and (iii) soil tillage can be timed more accurately using a recently developed day degree model.  相似文献   
67.
The binding of [3H]-paroxetine to membrane serotonin transporter (SERT) has been studied in membranes from different sources and subcellular fractions. From rat were membranes from venous blood platelets, brain total cortex, brain microsomes, brain crude and purified synaptosomes. Membranes were obtained from venous blood platelets from human volunteers and from brain cortex tissue from neurosurgery (cerebral lobectomies following craniocerebral injuries). The main finding was that the K D of paroxetine binding to the SERT was the same for platelet and nerve ending (synaptosomal) membranes. That parameter was significantly lower in membranes from brain microsomes and cortex total tissue. No species related difference was found, where comparison was possible, between human and rat tissue. The equality of K D of paroxetine binding to blood platelet membranes and to membranes from nerve endings appears to encourage the use of such membranes as a model for brain SERT. Binding at two different temperatures for several of the fractions suggests that paroxetine–SERT interaction is entropy-driven.  相似文献   
68.
69.
Three new coordination polymers, [CdL(H2O)3·H2O]n (1), [MnL(H2O)2]n (2) and [ZnL]n (3) (L = 2,2′-[1,4-bis(-benzamido)]diacetate) have been hydrothermally synthesized. Complex 1 and complex 2 are 1-D infinite zigzag chain and 2-D rectangular grid networks, respectively, in which are further stabilized by hydrogen bonds, thus affording two 3-D supramolecular frameworks. Complex 3 exhibits a (4, 4)-connected PtS topology. Moreover, an unusual phenomenon has been observed that the dimension of these coordination polymers gradually increases with the decrease of coordination numbers of metal ions. In addition, complex 1 exhibits a strong blue luminescence in the solid state at room temperature and may be potential candidate for luminescent materials.  相似文献   
70.
We present here a simple approach to identify domain boundaries in proteins of an unknown three-dimensional structure. Our method is based on the hypothesis that a high-side chain entropy of a region in a protein chain must be compensated by a high-residue interaction energy within the region, which could correlate with a well-structured part of the globule, that is, with a domain unit. For protein domains, this means that the domain boundary is conditioned by amino acid residues with a small value of side chain entropy, which correlates with the side chain size. On the one hand, relatively high Ala and Gly content on the domain boundary results in high conformational entropy of the backbone chain between the domains. On the other hand, the presence of Pro residues leads to the formation of hinges for a relative orientation of domains. The method was applied to 646 proteins with two contiguous domains extracted from the SCOP database with a success rate of 63%. We also report the prediction of domain boundaries for CASP5 targets obtained with the same method.  相似文献   
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