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81.
H. O. Kwanashie J. I. Ejiofor I. Abdu‐Aguye J. N. Nkweteyim M. R. Olanipekun 《Phytotherapy research : PTR》2009,23(2):236-240
Earlier pharmacological screening showed that siculine syrup (a traditional herbal remedy purported to be useful in the prevention and treatment of sickle cell pain – crises, due to sickle cell anaemia – SCA) had antisickling and analgesic activities as well as antimicrobial and diuretic effects. SCA is an important haemoglobinopathy in Africa and many other communities/countries worldwide, with relatively high morbidity and mortality. The present study was to determine the effects of the extract on various isolated muscle preparations – smooth, skeletal and cardiovascular. Siculine (4–20 µg/mL), like acetylcholine (40–400 µg/mL), contracted the isolated rat uterus concentration dependently. Similar effects were observed with the guinea‐pig ileum and rabbit jejunum (2–20 µg/mL). In contrast to these effects, the direct (muscle) and indirect (nerve) stimulations of rat phrenic nerve–diaphragm were relaxed by siculine (4 and 8 µg/mL) and d ‐tubocurarine (0.8 µg/mL). Siculine also concentration‐dependently decreased both the rate and force of contraction of guinea‐pig atria and rabbit heart and also resulted in a fall in cat blood pressure in a manner similar to those of acetylcholine. The possible therapeutic and/or toxicological consequences of these effects including the hypotensive activity is noteworthy since siculine syrup is used by the local population for the prevention and treatment of sickle cell pain crises. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
82.
17β-雌二醇对子宫内膜异位症患者在位子宫内膜间质细胞β-catenin mRNA和蛋白表达的影响 总被引:2,自引:0,他引:2
目的研究17β-雌二醇(17β-E2)对子宫内膜异位症(内异症)患者在位子宫内膜间质细胞β-catenin mRNA和蛋白表达的影响,探讨Wnt/β-catenin信号通路在介导雌激素促进内异症发生发展的作用。方法体外分离培养内异症患者在位子宫内膜间质细胞。用不同浓度17β-E2处理子宫内膜间质细胞48 h;此后选用10-10mol/L 17β-E2处理子宫内膜间质细胞12、24和48 h,逆转录聚合酶链反应(RT-PCR)和免疫印迹法(Western blotting)检测17β-E2处理前后子宫内膜间质细胞β-catenin mRNA和蛋白的表达水平。同法分析雌激素受体拮抗剂ICI182,780(10-6mol/L)对17β-E2促进β-catenin mRNA和蛋白表达的影响。免疫组织化学染色观察17β-E2作用后β-catenin在子宫内膜间质细胞中的定位。结果17β-E2能明显促进内异症患者在位子宫内膜间质细胞β-catenin mRNA和蛋白的表达,并呈剂量和时间依赖性,于10-10mol/L作用48 h最明显。雌激素受体拮抗剂ICI182,780能明显抑制17β-E2对子宫内膜间质细胞β-catenin mRNA和蛋白的表达。免疫组织化学染色发现17β-E2能促进β-catenin在子宫内膜间质细胞核内的表达。结论雌激素可能通过激活Wnt/β-catenin信号通路促进内异症在位子宫内膜的异位种植。 相似文献
83.
Asystole Following Left Ventricular Pacing 总被引:1,自引:0,他引:1
During biventricular ICD implantation, pacing the epicardial inferior posterior-lateral surface of the left ventricle via the coronary sinus produced asystole. The proposed mechanism is a Bezold-Jarisch reflex manifested by a drop in heart rate and blood pressure through direct C fiber stimulation. (PACE 2004; 27[Pt. I]:815–817) 相似文献
84.
Steven Elia Peter Liu Carol Chrusciel Alan Hilgenberg Charrisios Skourtis Demetrios Lappas 《Journal canadien d'anesthésie》1989,36(1):2-8
Global coronary blood flow and metabolism were measured in seven patients on the first postoperative day following coronary
revascularization to test the hypothesis that tracheal extubation produces adverse haemodynamic responses akin to those observed
during tracheal intubation. Regional coronary flow and metabolic measurements were made in five of the seven patients. Extubation
from a continuous positive airway pressure (CPAP) of 5 cm H2O was associated with a statistically significant rise in cardiac index from 3.44 ± 0.23 L · min-1 · m-2 to 3.73 ± 0.15L·min-1 ·m-2 related to an increase in stroke index, without significant changes in heart rate, mean arterial and pulmonary capillary
wedge pressure. Consequently the changes in myocardial oxygen consumption (8.52 ± 0.55 to 8.85 ± 0.93 ml · min-1) and coronary blood flow (172 ± 18 to 179 ± 17 ml·min-1) were less prominent than those reported during intubation, where substantial rises in myocardial oxygen consumption and
coronary flow occurred. Two patients experienced cardiac lactate production but there were no changes in systemic or coronary
haemodynamics, nor were there clinical or electrocardiographic signs of ischaemia. We conclude that extubation does not appear
to be associated with adverse systemic or coronary haemodynamic responses in patients following coronary bypass grafting.
However, the revascularized myocardium may remain vulnerable to anaerobic metabolism in the immediate postoperative period.
Pour savoir si comme ľintubation, ľextubation de la trachée provoque des perturbations hémodynamiques, on a mesuré le métabolisme
et la circulation coronarienne globale chez sept patients, au lendemain ďun pontage aorto-coronarien. On a aussi calculé les
valeurs régionales de ces mêmes variables pour cinq ďentre eux. Ľindex cardiaque de 3.44 ± 0.23 L · min-1 · m-2 sous pression positive en respiration spontanée (CPAP) de 5 cm. H2O s’est élevé à 3.73 ± 0.15 L · min-1 · m-2 post-extubation avec une augmentation significative du volume ďéjection. La fréquence cardiaque et les pressions artérielles
moyennes et capillaires pulmonaires n’ont pas changé. Ainsi ľaugmentation de la consommation ďoxygène du myocarde de 8.52
± 0.55 à 8.85 ± 0.93 ml · min-1 et celle du flot coronarien de 172 ± 18 à 179 ± 17 ml · min-1 ont été moindres que celles, importantes, déjà observées lors de ľintubation. On a noté chez deux patients une production
de lactate par le myocarde, sans changement de ľhémodynamic systémique et coronarienne non plus que de signe clinique ou électrocardiographique
ďischémie. Donc, après un pontage coronarien, ľextubation ne semble pas causer ďeffet néfaste sur les circulations systémique
et coronarienne, toutefois, le myocarde revascularisé peut demeurer sensible au métabolisme anaérobique. 相似文献
85.
Takayuki Murakami Atsushi Komiya Kunihisa Mikata Shigeki Kaneko Ichiro Ikeda 《International journal of urology》2007,14(3):240-241
Abstract: A 66-year-old man was referred to our hospital with chest discomfort and shortness of breath. Seven months previously he had undergone a laparoscopic left nephroureterectomy for a left renal pelvic tumor and was given two cycles of adjuvant chemotherapy (methotrexate, epirubicin and cisplatin). Echocardiogram showed an 8-mm sized mass extending from the right atrium into the right ventricle. On computed tomography, multiple lung tumors, as well as the right atrial and ventricular mass, were seen. The patient died of acute heart failure caused by right ventricular outflow obstruction. On autopsy, a right atrial and ventricular metastasis of the initial transitional cell carcinoma was found. The patient's cause of death was acute heart failure as a result of cardiac metastasis of his initial renal pelvic carcinoma. 相似文献
86.
Tadamasa Miyauchi Hiroshi Takiya Toshihiko Sawamura Eiji Murakami 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(4):206-209
Pericardial abscess is rare in healthy individuals, especially the amebic type. We report a case of pericardial abscess and
cardiac tamponade due to intrapericardial rupture of an amebic liver abscess. A 31-year old Japanese male complained of fever
to a local hospital. A liver mass was discovered in his left hepatic lobe by an abdominal echogram. He was referred to the
internal department of our hospital and was treated with quinolone antibiotics. Two weeks after medication, he suddenly complained
of epigastralgia and severe orthopnea and was admitted. Abdominal computed tomographic scan showed an enlarged liver mass,
and massive pericardial effusion suggested cardiac tamponade. He underwent an emergency subxiphoid partial pericardiectomy
under local anesthesia. 1,000 ml of light brownish fluid was removed and his condition improved. Although no ameba was cultivated
from the pus, the amebic serological test was positive. Metronidazole was administered and the patients was discharged 31
days after surgery. 相似文献
87.
蒋丽君 《中国中医药信息杂志》2005,12(9):17-18
目的观察按压骨穴对围绝经期妇女心脏植物神经功能的影响。方法设按压骨穴组30例、空白对照组30例。用美国BraemarDL700型动态心电检测仪,检测试验前后的心率变异性(HRV):TF代表总频,LF代表交感神经活性,HF代表迷走神经活性,LF/HF代表交感神经与迷走神经均衡性。结果按压骨穴后4项指标均有显著下降(P<0.01,P<0.05)。空白对照组变化不显著(P>0.05)。骨穴组4项指标的变化率与对照组比较均有显著性差异(P<0.01)。结论按压骨穴有抑制心脏交感神经活性的良性调整作用,此效应具有相对的特异性。 相似文献
88.
D M McSherry 《Statistics in medicine》1986,5(5):497-502
The independence Bayesian model has been used widely in computer programs designed to support clinical decision-making. A reasoning strategy has been developed to enable these programs to conduct clinically pertinent dialogue and explain their reasoning. It has been implemented in a program for the diagnosis of acute abdominal pain based on the Bayesian model of de Dombal et al. Several features of the dialogue design have been adopted from artificial intelligence research, including shared initiative and critiquing. The program adopts a flexible goal-driven strategy, attempting to confirm the clinician's diagnosis or rule out the likeliest alternative. Symptoms and signs are selected in order of their expected weights of evidence in favour of the hypothesized disease. 相似文献
89.
A Sultan C Piot D Mariano-Goulart J P Daures F Comte E Renard A Avignon 《Diabetic medicine》2006,23(4):410-418
AIMS: To assess the association between abnormal stress myocardial perfusion imaging (MPI) and cardiac events (CE) in asymptomatic patients with diabetes and with > or = 1 additional risk factor. Predictors of abnormal stress MPI were also evaluated. METHODS: Four hundred and forty-seven consecutive patients who underwent stress MPI were prospectively followed for 2.1 [0.5-4.1] years for the subsequent occurrence of hard CE (myocardial infarction and sudden or coronary death) and soft CE (unstable angina and ischaemic heart failure requiring hospitalization). Re-vascularization procedures performed as a result of the screening protocol were not included in the analysis. RESULTS: Follow-up was successful in 419 of 447 patients (94%), of whom 71 had abnormal MPI at baseline. Medical therapy was intensified in all subjects and especially in those with abnormal MPI. Twenty-three patients with abnormal MPI underwent a re-vascularization procedure. CEs occurred in 14 patients, including six of 71 patients (8.5%) with abnormal MPI and eight of 348 patients (2.3%) with normal MPI (P < 0.005). Only two patients developed a hard CE and 12 a soft CE. In multivariate analysis, abnormal MPI was the strongest predictor for CEs [odds ratio (OR) (95% CI) = 5.6 (1.7-18.5)]. Low-density lipoprotein cholesterol > or = 3.35 mmol/l [OR (95% CI) = 7.3; 1.5-34.7] and age > median [OR (95% CI) = 6.0 (1.2-28.6)] were additional independent predictors for CE. The independent predictors for abnormal MPI were male gender, plasma triglycerides > or = 1.70 mmol/l, creatinine clearance < 60 ml/min and HbA1c > 8%, with male gender the strongest [OR (95% CI) = 4.0 (1.8-8.8)]. CONCLUSIONS: Asymptomatic patients with diabetes in this study had a very low hard cardiac event rate over an intermediate period. This could be explained by the effects of intervention or by the low event rate in the background population. Randomized studies of cardiac heart disease screening are required in asymptomatic subjects with diabetes to determine the effectiveness of this intervention. 相似文献
90.