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991.
992.
目的:探讨自发性脑出血后再次出血与血压控制水平的相关性;方法:按照研究条件严格遴选2006年1月.2010年12月间,我科收治的高血压脑出血患者共计221例,依据其血压控制水平,将其分为〈140/80mmHg,140/80mmHg.160/100mmHg两个组别,分别总结两组发生再出血的病例数,对其发生率进行统计学分析(卡方检验),以P〈0.05为具有统计学意义;结果:两个组中,患者年龄、性别、GCS评分、出血部位、首次出血量、血肿密度、血肿形状等因素完全匹配,无明显统计学差异(P〉0.05),而两组血压控制水平与再出血具有明显的相关性(P〈0.05),血压控制水平〈140/80mmHg时,再出血的发生率为15.64%,明显低于140/80mmHg-160/100mmHg组的27.17%;结论:高血压脑出血后,患者血压水平控制在正常血压范围内,有望降低患者发生再次出血的风险。 相似文献
993.
目的:探讨瑞芬太尼复合七氟醚在颅内动脉瘤栓塞术中的临床效果。方法:回顾性分析在我院行择期颅脑动脉瘤栓塞术的70例患者的临床资料,按照随机序号的方式将其分为观察组和对照组各35例,观察组患者采用瑞芬太尼复合七氟醚麻醉,对照组采用瑞芬太尼复合异丙酚麻醉,对两组麻醉诱导前1min(T1)、麻醉诱导后1min(T2)、插管时(T3)、手术开始后30min(T4)以及拔管时(T5)患者的血压、心率变化及清醒后拔管时间进行记录和分析。结果:两组患者在T2时收缩压(Systolic blood pressure,SBP)、舒张压(Diastolic blood pressure,DBP)和心率(HeartRate,HR)均较T1明显下降,比较差异均有统计学意义(P〈0.05);观察组患者的清醒时间(5.1±1.5)min及拔管时间(15.5±7.5)min均明显短于对照组,两组比较差异有统计学意义(P〈0.05o结论:在进行颅内动脉瘤栓塞术时,选择使用瑞芬太尼复合七氟醚的麻醉方式,可使患者血流动力学较为稳定,术后苏醒较快,值得在临床推广应用。 相似文献
994.
Masaji Ogura Eiichi Katsunuma Tomoko Akabane Seiichi Ogawa 《Bioscience, biotechnology, and biochemistry》2013,77(1):235-236
An aminopeptidase was purified from an aqueous extract of mullet roe in the presence of 2-mercaptoethanol by fractionation with ammonium sulfate and column chromatography on DEAE-cellulose and Sephadex G-200. The molecular weight of the enzyme was 184,000 by gel filtration, and the enzyme appeared to consist of two homogenous subunits. The optimal pH and optimal temperature for activity were 7.4 and 45°C, respectively. Puromycin, p-chloromercuribenzoic acid, and o-phenanthroline inhibited the enzyme n on-competitively (their Ki = 1.34 μm, 0.113mm and 0.145 mm, respectively), while 2-mercaptoethylamine was competitive (Ki = 0.056 mm). The enzyme was also inhibited by l-amino acids, in particular glutamic acid. The enzyme could hydrolyze a variety of α-aminoacyl β-naphthylamides and was most active on l-alanyl-β-naphthylamide. Judging from these properties, the mullet roe aminopeptidase resembles soluble alanyl amino-peptidase [EC 3.4.11.14]. 相似文献
995.
江西省主要作物(稻、棉、油)生态经济系统综合分析评价 总被引:4,自引:0,他引:4
基于成本收益分析和能值分析理论,构建经济效益指标和生态经济效益指标,对江西省水稻(早稻和晚稻)、棉花、油菜种植系统的经济效益、生态经济综合效益进行分析和评价。经济效益方面,分析比较了单位面积作物成本构成,构建了净利润(Rev)和净利润率(Prof)两个经济效益指标;生态经济方面,分析比较了单位面积能值投入产出构成,构建了能值投入率、能值产出率、环境负载率、宏观经济能值等四个能值评价指标。计算结果表明江西省水稻、棉花和油菜等作物的生产成本占主导地位,价格因素是影响种植成本最重要的因素。水稻主要是以生产物资费用为主,而棉花和油菜以人工费用为主。从产值和收益来看,Rev大小为棉花>晚稻>早稻>油菜,Prof大小为晚稻>棉花>早稻>油菜。水稻、棉花和油菜种植系统对自然更新资源的依靠程度较低,系统的维系主要依赖于外部购买能值的投入,其构成与生产成本构成是一致的。水稻、棉花和油菜等作物的种植系统能值投入率比较高,大小为棉花>早稻>晚稻>油菜,能值产出率:油菜>棉花>晚稻>早稻,造成生态环境压力为晚稻>早稻>油菜>棉花,宏观经济能值大小为油菜>棉花>晚稻>早稻。结果表明,江西省水稻、棉花、油菜种植系统是高度开放的系统,主要依赖购买能值,但是系统产出率不高,其环境压力也不大。研究结果可为深入认识江西水稻、棉花和油菜等主要作物种植系统提供一个新的视角,并为种植业可持续发展提供一定的参考价值。 相似文献
996.
Two isomers of primary products formed by méthylene blue sensitized photooxidation of δ-tocopherol were separated by thin layer chromatography. The products were characterized by UV, IR and NMR spectra and were identified to be 8aS- and 8aR-hydroperoxy δ-tocopheryl dienones, respectively. On decomposition of the photooxidized α-, γ- and δ-tocopherols, to-copheryl quinone and tocopheryl quinone epoxide were formed. The effect of hydroperoxy 5-tocopheryl dienone on methyl linoleate peroxidation was examined. The hydroperoxy dienone formed by the photooxidation of tocopherols did not accelerate lipid peroxidation. 相似文献
997.
Hepatic encephalopathy (HE) is a complex neuropsychiatric syndrome that typically develops as a result of acute liver failure or chronic liver disease. Brain edema is a common feature associated with HE. In acute liver failure, brain edema contributes to an increase in intracranial pressure, which can fatally lead to brain stem herniation. In chronic liver disease, intracranial hypertension is rarely observed, even though brain edema may be present. This discrepancy in the development of intracranial hypertension in acute liver failure versus chronic liver disease suggests that brain edema plays a different role in relation to the onset of HE. Furthermore, the pathophysiological mechanisms involved in the development of brain edema in acute liver failure and chronic liver disease are dissimilar. This review explores the types of brain edema, the cells, and pathogenic factors involved in its development, while emphasizing the differences in acute liver failure versus chronic liver disease. The implications of brain edema developing as a neuropathological consequence of HE, or as a cause of HE, are also discussed. 相似文献
998.
Basak Akadam-Teker Ozlem Kurnaz Ender Coskunpinar Aynur Daglar-Aday Ozlem Kucukhuseyin Huseyin Altug Cakmak Erhan Teker Zehra Bugra Oguz Ozturk Hulya Yilmaz-Aydogan 《Gene》2013
Background
Hydroxymethylglutaryl-Coenzyme A Reductase (HMGCR) catalyzes the rate-limiting step of cholesterol biosynthesis. This enzyme is the target of the widely available cholesterol lowering statins. In this population-based case–control study, the frequencies of -911 C>A polymorphism (rs3761740) of the HMGCR gene in patients with coronary heart disease (CHD) and healthy subjects were investigated and the correlations between the different genotypes and hypercholesterolemia with cardiovascular risk factors were analyzed.Methods
The HMGCR genotypes were determined in 365 patients with CHD and 365 controls by PCR–RFLP assay. Anthropometric measurements were measured in all participants.Results
There was no significant difference in the genotype frequencies of the HMGCR polymorphism between the male subjects of both patient and control groups, however, the HMGCR-CC genotype was found to be more frequent in female patients with CHD than female controls (p = 0.002). The HMGCR-CC genotype showed higher total-cholesterol (TC) and LDL-cholesterol (LDL-C) levels than the CA + AA genotypes in male CHD patients (p = 0.018). Due to this significant sex interaction, a multivariate analysis was conducted on the patient group. In the multivariate logistic regression analysis, the HMGCR-CC genotype was significantly associated with age < 55 (OR = 2.837, p = 0.001) and TC ≥ 5.18 mmol/L (OR = 1.970, p = 0.027) in male subjects. However, this association was not observed in female patients (p > 0.05). This analysis confirmed that the HMGCR-CC genotype was associated with elevated TC levels in male CHD patients with age < 55 years.Conclusion
These results suggest that age and sex modify the contribution of the HMGCR-911 polymorphism to fasting serum TC, LDL-C levels and risk of CHD. 相似文献999.
《Electromagnetic biology and medicine》2013,32(2):165-172
This double-blind study tested the effects of pulsating electromagnetic field (PEMF) therapy sessions on the changes in peripheral cardiovascular function in a group of aging adults after 12 weeks of treatment. Each therapy session involved 15 min of exposure to low-frequency PEMF with asymmetrical waveforms emitted by the Impulser? Pro mattress. The treatment was provided 5 days per week for a total of 60 sessions. Resting blood pressure and arterial stiffness index were determined for peripheral cardiovascular function. Fifty-four older men and women (mean age 59.8 ± 3.5 yrs) completed the entire protocol involving either the PEMF or a sham treatment. The results include statistically significant reductions in systolic and pulse blood pressure, while no significant difference in diastolic pressure or the index of arterial stiffness was observed. These findings suggest that the PEMF treatment might be linked to improvements in peripheral resistance or circulation. 相似文献
1000.
Fires are one of the main causes of forest loss in the tropics. Understanding the dynamic edge effects is critical for managing fires and protecting forests. We measured and analysed trends in microclimatic conditions (air temperature, relative humidity and vapour pressure deficit) over 7 months along three transects extending from core savanna areas to core forest areas. We tested two hypotheses: (i) that the forest edge is subject to microclimatic edge effects, and (ii) that the depth of these edge effects increases during dry periods. Sharp changes in each microclimatic variable were consistently observed between savanna and forest throughout the study period. Microclimatic transitions took place within 5 m outside the forest boundary. Drought levels increased homogenously throughout the forest and were not disproportionately severe in the vicinity of the forest edge. We suggest that these results were related to the fact that the studied period was abnormally humid due to a La Niña episode, and that under such conditions the vulnerability of the forest edge to savanna fires is relatively low. Relatively wet conditions in the savanna close to the forest edge may promote forest expansion by limiting fire spread. Prescribed fires during humid years could reduce fuel loads in savanna without affecting the forest edge, which would prevent fires during the dry years associated with El Niño episodes from having severe impacts. 相似文献