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51.
We sought in this study to examine the effects of diurnal blood pressure variations upon common carotid artery (CCA) elasticity in selected subjects with uncomplicated moderate essential hypertension. Towards this end, 174 non-smoker subjects with stage I-II essential hypertension and without diabetes mellitus, left ventricular hypertrophy and carotid atherosclerosis, were classified as dippers and non-dippers according to the diurnal variation of >10% between mean daytime and night-time systolic and diastolic blood pressure (BP) in 24-h non-invasive ambulatory BP monitoring. CCA distensibility was derived by a combination of surface ultrasonographic data and simultaneous BP measurements at the brachial artery. The dippers and non-dippers were similar with respect to demographic characteristics. Non-dippers had significantly greater office systolic BP, 24-h systolic BP and ambulatory pulse pressure (PP) and significantly less (daytime-night-time) systolic and diastolic BP fall (by 16 mm Hg and 11 mm Hg respectively, P< 0.0001) compared to dippers. CCA distensibility was significantly reduced in non-dippers compared to dippers (by 0.89 dyne(-1)/cm(2/)10(-6), P < 0.05). Multiple linear regression analysis identified patient age and ambulatory PP as significant predictors of the CCA elasticity index. When patient age, 24-h systolic and diastolic BP were used as covariates in an analysis of covariance, the difference of CCA elasticity between dippers and non-dippers ceased to reach statistical significance. In contrast, when patient age, ambulatory PP, systolic (daytime-night-time) BP fall and diastolic (daytime-night-time) BP fall were used as covariates, the difference of CCA distensibility between dippers and non-dippers continued to be statistically significant. In conclusion, the excessive impairment of CCA elastic properties in non-dippers compared to dippers hypertensive seems to be ascribed to the increased of total 24-h haemodynamic load and not to the circadian pattern of BP. Journal of Human Hypertension (2000) 14, 813-818  相似文献   
52.
Background and hypothesis: In vitro studies have shown that atrial natriuretic peptide (ANP) causes relaxation of pre-constricted blood vessel strips and inhibits the contraction of isolated vessels in response to norepinephrine and angiotensin II. The present study examined the effects of exogenous ANP on the coronary collateral blood flow during angioplasty. Methods: We studied 15 patients undergoing elective balloon angioplasty during the second and third balloon inflations. A Doppler flow guidewire was advanced distal to the lesion and used for the estimation of coronary blood flow velocity. After the second balloon inflation, 25 ng/kg/min of ANP were administered intracoronarily for 8 min. Electrocardiogram, pressure, and flow velocity were recorded immediately before each balloon deflation. Fourteen other patients served as controls and received normal saline infusion. Results: Velocity time integral increased from 65 ± 40 to 79 ± 46 mm (p < 0.05) during the third balloon inflation, whereas ST deviation decreased from 1.3 ± 0.9 to 0.7 ± 1.0 mV (p< 0.05). These variables did not change in the control group during the two tested balloon inflations. Conclusion: Exogenous ANP augments coronary collateral blood flow and ameliorates myocardial ischemia during angioplasty.  相似文献   
53.
非酒精性脂肪性肝炎(non—alcoholicsteatohepatitis,NASH)现已成为肝移植愈来愈重要的基础肝病。鉴于晚期NASH患者常并存多种影响肝移植转归的临床问题,而至今尚无针对NASH患者进行肝移植的评估和治疗指南,为此英国移植学会(British Transplant Society,BTS)邀请相关专家制定了指南,以指导肝移植前后NASH患者的处理。  相似文献   
54.
BackgroundThe contribution of atrial and ventricular function in neurocardiogenic syncope (NCS) pathophysiology is elusive.HypothesisWe assessed the influence of echocardiographic properties to the age of presentation and NCS recurrences.MethodsWe assigned 124 patients with symptoms suggesting NCS, to those with syncope initiation at age <35 (group A, n = 56) and >35 years (group B, n = 68). Echocardiographic indices were measured before head‐up tilt test (HUTT).ResultsA total of 55 had positive HUTT (44%) with a trend favoring group A (p = .08). Group A exhibited lower left atrial (LA) volume index (17 ± 6 vs. 22 ± 11 ml/m2, p = .015), higher LA ejection fraction (69 ± 10 vs. 63 ± 11%, p = .008), LA peak strain (reservoir phase 41 ± 13 vs. 31 ± 14%, p = .001, contraction phase 27 ± 11 vs. 15 ± 10%, p < .001) and LA peak strain rate (reservoir phase 1.83 ± 1.04 vs. 1.36 ± 0.96 1/s, p = .012, conduit phase 2.36 ± 1.25 vs. 1.36 ± 0.78 1/s, p = .001). Group A showed smaller minimum right atrial (RA) volume, better RA systolic function, superior left ventricular diastolic indices, and lower filling pressures. Group A patients were more likely to have >3 recurrences (82.0% vs. 50.1%, p < .05).ConclusionsPatients with younger age of NCS onset and more syncopal recurrences manifest smaller LA and RA dimensions with distinct patterns of systolic and diastolic function and better LA reservoir and contraction properties. These findings may indicate an increased susceptibility to preload reduction, thereby triggering the NCS mechanism.  相似文献   
55.
We sought to investigate the prevalence of left main coronary artery significant stenosis (LMSS) (>or=50% of the luminal diameter) in an angiographic series of patients, to describe the associated coronary stenoses, and to assess the influence of age and gender on these findings. The angiograms of 17,323 consecutive patients from January 1, 1984 to December 31, 2003 were retrospectively analyzed. LMSS was found in 823 patients (4.8%) and was more predominant in men (p <0.001). Men with LMSS (median age 63 years, interquartile range 57 to 69) were younger than the women (median age 67 years, interquartile range 61 to 72, p <0.001). Logistic regression analyses revealed male gender (odds ratio [OR] 1.79, 95% confidence interval [CI] 1.46 to 2.18, p <0.001) and age (OR 1.05, 95% CI 1.04 to 1.06, p <0.001) as independent predictors of LMSS. In the total series, luminal narrowing >or=50% in the right coronary artery, the left circumflex artery, the left anterior descending artery, the intermediate artery, first and second obtuse marginal branch, posterior descending artery, and posterolateral branch was significantly more frequent in association with LMSS. Approximately half of the patients with LMSS also had triple-vessel disease. Co-existent disease in 3 major vessels with minor branches was more evident in men (men/women OR 1.77, 95% CI 1.08 to 2.88, p = 0.02). In contrast, LMSS without lesions in any of the other coronary arteries was found in [corrected] 4.7% of patients with LMSS, and this was more frequent in women (men/women OR 0.31, 95% CI 0.15 to 0.61, p = 0.001). In conclusion, men presented more frequently with LMSS and at a younger age than women. Also, LMSS with co-existent triple-vessel disease was more common in men.  相似文献   
56.
57.
Dolberg OT, Dannon PN, Schreiber S, Grunhaus L. Transcranial magnetic stimulation in patients with bipolar depression: a double blind, controlled study. Bipolar Disord 2002: 4(Suppl. 1): 94–95. © Blackwell Munksgaard, 2002  相似文献   
58.
Terasawa  T; Ogawa  M; Porter  PN; Karam  JD 《Blood》1980,56(1):93-97
We examined gamma-globin-chain biosynthesis by adult and umbilical cord blood or erythropoietic bursts in methylcellulose clonal culture and gamma-chain synthesis by cord blood reticulocytes. Globin chains were labeled with 14C-amino acids and guantitated by using autoradiography or fluorography. Alpha, beta, and G gamma and A gamma chains were separated by isoelectric focusing in polyacrylamide gels containing 8 M urea and 3% Nonidet P-40 (a nonionic detergent). Time course examinations of the gamma-chains synthesized by the bursts revealed no changes in the G gamma:A gamma ratio between days 10 and 18 of culture. The ratio of G gamma/(G gamma + A gamma) in cultures of adult circulating erythroid precursors was 0.38 +/- 0.09, which corresponds to the known ratio in adult peripheral blood erythrocytes. The relative G gamma-chain biosyntheses in the cord blood bursts and reticulocytes were 0.56 +/- 0.02 and 0.66 +/- .008, respectively. Both are intermediate between the accepted newborn and adult ratios. Natal erythropoietic precursors appear to be in the transitional stage with respect to the switching of G gamma-A gamma ratios.  相似文献   
59.
Muckle — Wells syndrome (MWS) is a rare autosomal dominant disease that belongs to a group of hereditary periodic fever syndromes. It is part of the wider spectrum of the cryopyrin-associated periodic syndrome (CAPS) which has only rarely been described in non-Caucasian individuals. It is characterized by recurrent self-limiting episodes of fever, urticaria, arthralgia, myalgia and conjunctivitis from childhood. Progressive sensorineural hearing loss and amyloidosis are two late complications. MWS is caused by gain of function mutations in the NLRP3 gene, which encodes cryopyrin, a protein involved in regulating the production of proinflammatory cytokines. We report two patients with MWS in an Indian family associated with the p.D303N mutation in the NLRP3 gene. These findings promote awareness of these hereditary periodic fever syndromes as a cause for recurrent fevers from childhood in the Indian population.KEY WORDS: Hereditary periodic fever, D303N mutation, Indian family, Muckle—Wells syndrome, p.D303N mutation  相似文献   
60.
The purpose of this study was to determine the prevalence of IgM and IgG antibodies against Bartonella henselae and B. quintana in a healthy Greek population using a commercially available immunofluorescent test (Focus test). Five hundred healthy individuals were divided by sex into four age groups and three groups according to contact with cats. IgM antibodies were not detected in any of the subjects examined, while 99 (19.8%) and 75 (15%) were IgG seropositive to B. henselae and to B. quintana, respectively. No statistical difference in the seropositivity was observed among these groups. The IgG antibody titers ranged from 1/64 to 1/256 for B. henselae and from 1/64 to 1/512 for B. quintana. A high percentage (12.4%) of cross-reactivity between the two species was observed. Our data show that the prevalence of both Bartonella species in Greece is high. However, low IgG antibody levels are not sufficient evidence of active infection.  相似文献   
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