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301.
苏旭;刘玉萍;杨淳彬;柯君;拉本 《植物研究》2013,33(2):139-144
通过对披碱草属中小颖组、宽颖组和长颖组种类外部形态的观察,总结了3组植物外部形态特征的异同,探讨了形态学特征的分类学意义。同时,根据3组植物外部形态性状—花序、小穗、小花、以及内稃的演化趋势,分析了各组的演化关系和系统位置。结果表明:小颖组最原始,宽颖组较进化,长颖组最高级;小颖组可能直接派生了较进化的宽颖组,并在宽颖组的基础上进而产生了最高级的长颖组。此外,本文对披碱草属参试种的系统关系也作了一定程度的探讨,结果显示圆锥披碱草最原始,墨西哥披碱草最进化,其余参试种居于两者之间。上述研究工作为整个披碱草属系统与进化方面的探讨提供了形态学方面的理论证据。 相似文献
302.
Cláudia SF Queiroga Ana S Almeida Paula M Alves Catherine Brenner Helena LA Vieira 《BMC cell biology》2011,12(1):10
Background
Low concentrations of carbon monoxide (CO) protect hepatocytes against apoptosis and confers cytoprotection in several models of liver. Mitochondria are key organelles in cell death control via their membrane permeabilization and the release of pro-apoptotic factors. 相似文献303.
观察栀子提取物对实验性2型糖尿病大鼠血糖、血脂及同型半胱氨酸水平的影响.采用Wistar雄性大鼠70只,随机抽取10只作为正常对照组,喂以普通维持饲料,其余60只高糖高脂饲料喂养4周后,ip链脲佐菌素(STZ)30 mg/kg建立2型糖尿病模型,7d后选取成模大鼠50只随机分为模型对照组(生理盐水)、盐酸二甲双胍对照组、栀子提取物低、中、高剂量组(0.2、0.4、0.6 g/kg),每组10只.连续ig给药4周后,观察各组大鼠血糖、血脂及同型半胱氨酸水平等变化.栀子提取物ig能降低糖尿病大鼠的血糖、甘油三酯(TG)、胆固醇(TC)、低密度脂蛋白(LDLC),同时能升高高密度脂蛋白(HDLC),降低同型半胱氨酸水平. 相似文献
304.
R. MORCUENDE P. PÉEREZ R. MARTÍNEZ-CARRASCO I. MARTIN DEL MOLING L. SANCHEZ DE LA PUENTE 《Plant, cell & environment》1996,19(10):1203-1209
Wheat (Triticum aestivum L.) ears were removed to investigate long-term regulation of photosynthesis by sink demand at ambient CO2 and 22 °C. The CO2 level was also increased to 660 μmol mol?1 and temperature was lowered to 5 °C to examine short-term responses of photosynthesis to low sink demand. Sink removal inhibited photosynthesis and increased leaf levels of glucose, fructose and ribulose-1, 5-bisphosphate (RuBP), and the glucose-6-phosphate (G6P)/fructose-6-phosphate (F6P) and RuBP/3-phosphoglycerate (PGA) ratios under growth conditions, but had no effect on the activity and activation state of ribulose-1, 5-bisphosphate carboxylase oxygenase (Rubisco) either under growth or short-term conditions, suggesting an inhibition of photosynthesis by decreased in vivo catalysis of Rubisco. Photosynthesis increased similarly in eared and earless shoots after a rise in CO2 concentration, and the ratio of triose-phosphates (glyceraldehyde 3-phosphate and dihydroxyacetone phosphate, TP) to PGA was similar or higher for removed than intact ears, suggesting that feedback inhibition of photosynthesis was not caused by a limitation of ATP synthesis in chloroplasts. Under short-term conditions (660 μmol mol?1 CO2, 5 °C), TP and RuBP levels and the TP/PGA and TP/RuBP ratios were increased by sink removal, indicating an additional limitation of photosynthesis by the rate of RuBP regeneration. 相似文献
305.
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307.
Hussam F. AlFaleh Mostafa Q. Al Shamiri Anhar Ullah Khalid F AlHabib Ahmad Salah Hersi Shukri AlSaif Khalid AlNemer Amir Taraben Asif Malik Ahmed M Abuosa Mimish LA Tarek Kashour 《PloS one》2015,10(4)
Background
Saudi Arabia has a non-Saudi workers population. We investigated the differences and similarities of expatriate non-Saudi patients (NS) and Saudi nationals (SN) presenting with acute coronary syndromes (ACS) with respect to therapies and clinical outcomes.Methods
The study evaluated 2031 of the 5055 ACS patients enrolled in the Saudi Project for Assessment of Acute Coronary Syndrome (SPACE) from 2005 to 2007. Propensity score matching and logistic regression analysis were performed to account for major imbalances in age and sex in the two groups.Results
The mean patient age was 56.2±9.8, and 83.5% of the study cohort were male. SN were more likely to have risk factors of atherosclerosis. ST-elevation MI (STEMI) was the most common ACS presentation in NS, while non-ST ACS was more common in SN. The median symptom-to-door time was significantly greater in NS patients (Median 175 min (197) vs. 130 min (167), p=0.027). The only difference in pharmacological therapies between the two groups was that NS were more likely to receive fibrinolytic therapy. NS were less likely than SN to undergo percutaneous coronary interventions (PCI; 32.6% vs. 42.8%, p=0.0001) or primary PCI (7.8% vs. 22.8%, p<0.001). Hospital mortality, cardiogenic shock, and heart failure were significantly higher in NS compared to SN. After adjusting for baseline variables and therapies, the odds ratios for hospital mortality and cardiogenic shock in NS were 2.9 (95% CI 1.5–6.2, p=0.004) and 2.8 (95% CI 1.5–4.9, p<0.001), respectively.Conclusion
Our findings indicate disparities in hospital care between NS and SN ACS patients. NS patients had worse hospital outcomes, which may reflect unequal health coverage and access-to-care issues. 相似文献308.
NR Campbell Burgess E BC Choi G Taylor E Wilson J Cleroux JG Fodor LA Leiter D Spence 《CMAJ》1999,160(9):S1-S6
OBJECTIVE: To provide updated, evidence-based recommendations for health care professionals on lifestyle changes to prevent and control hypertension in otherwise healthy adults (except pregnant women). OPTIONS: For people at risk for hypertension, there are a number of lifestyle options that may avert the condition--maintaining a healthy body weight, moderating consumption of alcohol, exercising, reducing sodium intake, altering intake of calcium, magnesium and potassium, and reducing stress. Following these options will maintain or reduce the risk of hypertension. For people who already have hypertension, the options for controlling the condition are lifestyle modification, antihypertensive medications or a combination of these options; with no treatment, these people remain at risk for the complications of hypertension. OUTCOMES: The health outcomes considered were changes in blood pressure and in morbidity and mortality rates. Because of insufficient evidence, no economic outcomes were considered. EVIDENCE: A MEDLINE search was conducted for the period January 1996 to September 1996 for each of the interventions studied. Reference lists were scanned, experts were polled, and the personal files of the authors were used to identify other studies. All relevant articles were reviewed, classified according to study design and graded according to level of evidence. VALUES: A high value was placed on the avoidance of cardiovascular morbidity and premature death caused by untreated hypertension. BENEFITS, HARMS AND COSTS: Lifestyle modification by means of weight loss (or maintenance of healthy body weight), regular exercise and low alcohol consumption will reduce the blood pressure of appropriately selected normotensive and hypertensive people. Sodium restriction and stress management will reduce the blood pressure of appropriately selected hypertensive patients. The side effects of these therapies are few, and the indirect benefits are well known. There are certainly costs associated with lifestyle modification, but they were not measured in the studies reviewed. Supplementing the diet with potassium, calcium and magnesium has not been associated with a clinically important reduction in blood pressure in people consuming a healthy diet. RECOMMENDATIONS: (1) It is recommended that health care professionals determine the body mass index (weight in kilograms/[height in metres]2) and alcohol consumption of all adult patients and assess sodium consumption and stress levels in all hypertensive patients. (2) To reduce blood pressure in the population at large, it is recommended that Canadians attain and maintain a healthy body mass index. For those who choose to drink alcohol intake should be limited to 2 or fewer standard drinks per day (maximum of 14/week for men and 9/week for women). Adults should exercise regularly. (3) To reduce blood pressure in hypertensive patients, individualized therapy is recommended. This therapy should emphasize weight loss for overweight patients, abstinence from or moderation in alcohol intake, regular exercise, restriction of sodium intake and, in appropriate circumstances, individualized cognitive behaviour modification to reduce the negative effects of stress. VALIDATION: The recommendations were reviewed by all of the sponsoring organizations and by participants in a satellite symposium of the fourth international Conference on Preventive Cardiology. They are similar to those of the World Hypertension League and the Joint National committee, with the exception of the recommendations on stress management, which are based on new information. They have not been clinically tested. SPONSORS: The Canadian Hypertension Society, the Canadian Coalition for High Blood Pressure Prevention and Control, the Laboratory Centre for Disease Control at health Canada, and the Heart and Stroke Foundation of Canada. 相似文献
309.
香蕉束顶病毒基因Ⅰ的克隆及序列分析 总被引:5,自引:0,他引:5
以中国漳州地区感染BBTV的香蕉组织总DNA为模板,根据我国台湾地区BBTV分离物基因组Ⅰ序列,设计并合成了一对引物,通过PCR扩增出约500bp的片段。利用pBluescriptⅡSK T-载体获得此片段的克隆,经测序表明为BBTV组分Ⅰ的部分序列。由已测知的BBTV基因组Ⅰ序列设计一对相邻引物,以我国漳州的感染BBTV香蕉组织总DNA为模板,通过PCR坟增出约1.1kb的片段。利用pBlues 相似文献
310.
KATALIN PECSENYE JUDIT BERECZKI BORBÁLA TIHANYI REA TÓTH LÁSZLÓ PEREGOVITS ZOLTÁN VARGA 《Biological journal of the Linnean Society. Linnean Society of London》2007,91(1):11-21
The present study aimed to analyse the level of genetic variation in the eastern Central European (Slovenia, Hungary, and Romania/Transylvania) populations of the Large Blues ( Maculinea ) to analyse the pattern of differentiation both between and within the species. One objective was to compare the level of differentiation between the two disputed species ( Maculinea alcon and Maculinea rebeli ) with that among the other species. Imagos were collected from 23 localities in eastern Central Europe in 2002. Enzyme polymorphism was analysed using polyacrylamide gel electrophoresis. Fourteen enzyme loci were studied in all samples. In the analysis of the data, F -statistics and Nei's genetic distances were calculated and a dendrogram (unweighted pair group method with arithmetic mean) was constructed on the basis of the distance matrix. A multivariate analysis of variance was performed to study the pattern of genetic differentiation among the samples. Principal component analysis analysis was also carried out using the allele frequency data of the samples. Our results indicated that the large blues are generally less polymorphic than other European lycaenid butterflies studied. At the same time, the level of genetic differentiation was high, even among local populations within the species. A low level of genetic variation within the populations coupled with strong differentiation among them implies the effect of genetic drift. Strong genetic differentiation of four Maculinea species ( M. alcon , Maculinea teleius, Maculinea nausithous , and Maculinea arion ) was confirmed. Significant differentiation was not found between M. alcon and M. rebeli . © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 91 , 11–21. 相似文献