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2.
目的探讨心房充血分数(AFF)在评价高血压患者左室舒张功能方面的临床应用价值。方法应用声学定量技术(AQ)对40名高血压患者及40名正常人的AAF值,快充血率峰值(PRFR)进行测定,并兼测了二尖瓣口E峰峰值速度与A峰峰值速度比(EV/AV)。结果高血压患者的AFF值明显高于正常人(P<0·001);而PRFR、EV/AV值明显低于正常人(P<0·001~P<0·05)。且所有受试者的AFF值与EV/AV值、PRFR值分别呈负相关(r=-0·51;r=-0·61)。结论AFF能够客观的反映高血压患者的左室舒张功能变化,对鉴别左室舒张功能异常有一定的诊断意义。 相似文献
3.
M Mian A Azzara' D Benetti L Ruocco A Bertelli F Ambrogi 《International journal of tissue reactions》1987,9(6):459-463
Rhein (R: 1,8-dihydroxy-3-carboxyanthraquinone) is the active metabolite of the drug diacetylrhein (DAR), an anthraquinone molecule which has recently been proposed for the long-term treatment of osteoarthrosis. Its action mechanism in rheumatic pathology has not been fully explained. It is known that DAR, while not inhibiting the formation of prostaglandins, inhibits certain proteolytic enzymes, and acts on phlogistic cells by lysosomal enzymic and superoxide-anion modifications. Moreover DAR modifies phagocytic functions and the motility of cells. This paper is a contribution to the clarification of the last point, namely the effect of rhein on cell motility. It reports that in vitro no effect of R on random migration was found, but instead a double inhibiting effect on chemotaxis (i.e. a low-dosage and a high-dosage effect). Furthermore, R did not modify the inhibition or induce modification of chemotaxis by vinblastine. Finally R cancelled the stimulating effect of ionic potassium. The results thus indicate that R acts on the chemotaxis of the leukocytes with a complex action at different doses. The action mechanism is probably due to a membrane effect, since rhein (R) did not modify the chemotaxis-inhibiting activity of vinblastine but did interfere with the stimulating effect of K+. 相似文献
4.
Okan Bilge Yelda Pinar Mehmet Asim Ozer Figen Govsa 《Journal of plastic, reconstructive & aesthetic surgery》2007,60(10):1120-1126
The lumbrical muscles are located in the midpalm, dorsal to the palmar aponeurosis. The main function of these muscles is an indirect contribution to interphalangeal joint extension by decreasing the flexor effect of the flexor digitorum profundus muscle. Due to their minor biomechanical functions and suitable constructions, these muscles have been preferred in reconstructive surgery as local transposition flaps or pedicled flaps. Despite the surgical and clinical importance, vascular anatomical studies of these muscles are not well represented in the current literature. This study was performed in the Department of Anatomy of the Faculty of Medicine of the Ege University. Thirty-four cadaver hands, injected with red-coloured latex were used, and we aimed to describe the morphometry and vascular anatomy of the lumbrical muscles. We measured the length and width of the muscles, after removing their epimisium, and the diameter and length of the arteries to the muscles. The outcomes of our study determined that the length and width of the lumbrical muscles were reduced significantly from radial towards ulnar sides. The lumbrical muscles were supplied from both their palmar and dorsal surfaces by both superficial and deep palmar arches and/or their branches. We also described the level of entry of the dominant arteries for each lumbrical muscle and measured the size of the vessels and muscles to guide some surgical approaches. This anatomical study could guide for some surgical approaches and reduce the deficiency about the vascular anatomical patterns of the lumbrical muscles in the literature. 相似文献
5.
Using rare earth element tracers and neutron activation analysis to study rill erosion process. 总被引:1,自引:0,他引:1
Mian Li Zhan-bin Li Weng-feng Ding Pu-ling Liu Wen-yi Yao 《Applied radiation and isotopes》2006,64(3):402-408
Spatially averaged soil erosion data provide little information on the process of rill erosion. The dynamically varied data on the temporal and spatial distributions in the rill erosion process are needed to better understand the erosion process and reveal its innate characteristics. The objectives of this study were to examine the feasibility and effectiveness of rare earth element (REE) tracers and the neutron activation analysis (NAA) method on the study of the rill erosion process and to reveal quantitatively the relationships and characteristics of temporal and spatial distributions of sediment yield in rill erosion. Four REEs were used to study the changeable process of rill erosion at 4 slope positions. Four water inflow rates were applied to a 0.3 x 5 m soil bed at 3 slopes of 10.5%, 15.8% and 21.2% in scouring experiments. All of the runoff was collected in the experiment. Each sample was air-dried and well mixed. Then 20 g of each sample was sieved through 100-mesh and about a 50 mg sample was weighed for analysis of the four elemental compositions by NAA. Results indicate that the REE tracers and NAA method can be used to not only quantitatively determine soil erosion amounts on different slope segments, but also to reveal the changeable process of rill erosion amount. All of the relative errors of the experimental results were less than 25%, which is considered satisfactory on the study of rill erosion process. 相似文献
6.
7.
α-Alkylation of amino acid derivatives: Synthesis and chiral resolution of [C]β-aminoisobutyric acid
A synthesis of 11C-labeled β-aminoisobutyric acid ([11C]β-AIB) and its enantiomeric resolution by high performance liquid chromatography (HPLC) are reported. β-Alanine ethyl ester 2 was converted to benzaldimine-β-alanine ethyl ester 3 in 87% yield. Treatment of the imine derivative 3 with lithium diisopropylamide (1.1 eq) in tetrahydrofuran at −78 °C, followed by addition of cold iodomethane (1.1 eq) produced the α-methylated benzaldimine-β-alanine ethyl ester 4 in 73% chemical yield. Deprotection of the amino group by acidic hydrolysis followed by basic hydrolysis of the ester group produced the desired product 1 in 37% chemical yield. Labeling was accomplished using [11C]methyl iodide. The radiola-beled product was purified by HPLC using a semipreparative reversed-phase C-18 column and 2 mM phosphate buffer (pH 5.9) as the mobile phase. The synthesis time was 35–40 min including HPLC purification, with 20–60% radiochemical yield (decay corrected). Radiochemical purity was >99%, with average specific activity being 450 mCi/μmol. Enantiomers of β-AIB were well separated by analytical HPLC using a chiral column and aqueous perchloric acid as the mobile phase. (S)-β-AIB was eluted at 17.4 min and the (R)-enantiomer was eluted at 20.0 min when the jacketed column was maintained at low temperature by circulation of ice-cold water, and the pH of the mobile phase was 1.05. 相似文献
8.
1-beta-D-Arabinofuranosyl-2-amino-1,4(2H)-4-iminopyrimidine (ara-AIPy), a new deaminase-resistant analog of cytarabine, exhibited extremely potent antitumor activity against P388 leukemia [400 mg/kg on Days 1-5; increase in life span (ILS), 211%] and significant inhibition against Lewis lung carcinoma (inhibition of tumor weight, 68%) and mammary adenocarcinoma 755 (inhibition of tumor weight, 82%). Schedule-dependency studies indicate that this drug, unlike cytarabine, was effective irrespective of its treatment schedules. The drug exhibited therapeutic efficacy against established P388 tumor transplants (400 mg/kg on Days 3-7; ILS, 131%) and inhibited the tumor growth effectively even when administered as a single dose on Day 1 by both ip (2000 mg/kg; ILS, 150%) and iv (500 mg/kg; ILS, 68%) routes. Ara-AIPy was most effective when administered on Days 1, 3, 5, 7, and 9 after tumor transplantation (400 mg/kg; ILS, 210%, with 50% of animals 60-day survivors). Ara-AIPy inhibited the growth of L1210 leukemia when both the tumor transplantation and the drug treatment were administered by iv route (500 mg/kg on Days 1, 5, and 9; ILS, 181%). The routes of administration of ara-AIPy experiments showed that the drug was effective by both ip and iv routes of administration; however, better therapeutic values were obtained by ip schedules. These studies demonstrate that ara-AIPy exhibits highly significant and broad-spectrum antitumor activity against a variety of experimental animal tumor models and suggest a possible future role for this drug in the treatment of human neoplasia. 相似文献
9.
养阴清热、宣痹通络法治疗类风湿性关节炎的临床研究 总被引:5,自引:0,他引:5
目的 观察清络通痹颗粒治疗类风湿性关节炎阴虚络热证的临床疗效。方法 将118例患者随机分为清络通痹颗粒治疗组63例和雷公藤多甙片对照组55例,观察用药前后主要症状、体征和实验室检测指标的变化。结果 治疗组的临床治愈率为9.52%,临床治愈显效率为38.10%,总有效率为90.48%,疗效明显优于对照组的0%、20%、83.64%(P<0.05);治疗组的类风湿因子滴度、血沉、C反应蛋白、免疫球蛋白也明显降低,与对照组相比差异显著(P<0.05或P<0.01)。结论 清络通痹颗粒具有抗炎镇痛、调节免疫紊乱等作用,从而达到控制病情的治疗效果。 相似文献
10.
Cankurtaran Ozlem Olgac Guven Kutlu Cemal Asim 《Indian Journal of Thoracic and Cardiovascular Surgery》2004,20(2):91-92
Indian Journal of Thoracic and Cardiovascular Surgery - 相似文献