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151.
OBJECTIVES: The goal of this study was to investigate the possible role of transesophageal echocardiography in the evaluation of patients with clinical pacemaker syndrome. BACKGROUND: Several reports on transthoracic echocardiographic features of ventricular pacing were described; however, no previous study of transesophageal echocardiography has been undertaken in patients at the severe end of pacemaker syndrome who need reprogramming of dual-chamber pacing for symptom relief. METHODS: Twelve patients with ventricular-inhibited pacemakers (VVI) with clinical symptomatic pacemaker syndrome (group I) and 10 patients with VVI without pacemaker syndrome (group II) were prospectively studied. The two groups were pacemaker dependent and had persistent ventriculoatrial conduction. Transesophageal echocardiographic parameters were assessed in group II and within 6 hours before reprogramming to the DDD mode in group I. Follow-up transesophageal echocardiographic study was performed 28+/-5 days after reprogramming in group I. RESULTS: All patients in group I had subjective improvements of symptoms after DDD reprogramming. The atrial reverse flow velocities of pulmonary veins in group I before reprogramming were significantly higher in group II (39.3+/-11.4 versus 15.7+/-13.5 cm/sec, p < 0.0001). Spontaneous echo contrast in the descending aorta was detected in all patients from group I before reprogramming. The prevalence of significant mitral regurgitation (> or = moderate) was significantly higher in group I before reprogramming than in group II (67% versus 8%, p = 0.01). Significant mitral regurgitation and spontaneous echo contrast in the descending aorta in group I disappeared after reprogramming to the DDD mode. CONCLUSIONS: Transesophageal echocardiography provides physiologic, pacemaker-related hemodynamic changes in paced patients. Significantly higher atrial reverse flow velocities of pulmonary veins, increased frequency of spontaneous echo contrast in the descending aorta, and significant mitral regurgitation are peculiar echocardiographic findings in patients with VVI with clinical pacemaker syndrome. 相似文献
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153.
GS Huggins RC Pasternak NM Alpert AJ Fischman H Gewirtz 《Canadian Metallurgical Quarterly》1998,98(13):1291-1296
BACKGROUND: We tested the hypothesis that correction of hyperlipidemia improves coronary vasodilator response and maximal perfusion in myocardial regions having substantial impairment of pretreatment vasodilator capacity. METHODS AND RESULTS: Measurements of myocardial blood flow were made with PET [13N]ammonia in 12 patients with ischemic heart disease (11 men; age, 65+/-8 years [mean+/-SD]) at rest and during adenosine at 70 and then 140 microg . kg-1 . min-1 for 5 minutes each before and approximately 4 months after simvastatin treatment (40 mg daily). Simvastatin reduced LDL (171+/-13 before versus 99+/-18 mg/dL after simvastatin, P<0.001) and increased HDL (39+/-8 versus 45+/-9 mg/dL, P<0.05). Myocardial segments were classified on the basis of pretreatment blood flow response to 140 microg . kg-1 . min-1 adenosine as normal (flow >/=2 mL . min-1 . g-1) or abnormal (flow <2 mL . min-1 . g-1). In normal segments, baseline myocardial blood flow (0.95+/-0.32) increased (P<0.001) at both low- (1.62+/-0.81) and high- (2.63+/-0.41) dose adenosine and was unchanged both at rest and with adenosine after simvastatin. In abnormal segments, myocardial blood flow at rest (0. 73+/-0.19) increased at low- (1.06+/-0.59, P<0.02) and high- (1. 29+/-0.33, P<0.01) dose adenosine. After simvastatin, myocardial blood flow increased more compared with pretreatment at both low- (1. 37+/-0.66, P<0.05 versus pretreatment) and high- (1.89+/-0.79, P<0. 01 versus pretreatment) dose adenosine. CONCLUSIONS: Short-term lipid-lowering therapy increases stenotic segment maximal myocardial blood flow by approximately 45%. The mechanism involves enhanced, flow-mediated dilation of stenotic epicardial conduit vessels and may account at least in part for the efficacy of lipid lowering in secondary prevention trials and in reducing ischemic episodes in ambulatory patients. 相似文献
154.
155.
AE Omu S al-Othman AS Mohamad NM al-Kaluwby S Fernandes 《Canadian Metallurgical Quarterly》1998,43(10):857-864
OBJECTIVE: To investigate the effect of antibiotic therapy on seminal infection. STUDY DESIGN: The seminal plasma of 50 men was evaluated in three groups: (1) men with seminal infection (20), (2) men with leukocytospermia only (18), and (3) men of proven fertility (12). The evaluation protocol included semen analysis, culture and antibiotic sensitivity test, total antioxidant activity, alpha-tocopherol and retinol, T-helper cytokines, IL-2, IL-8, IL-4 and antisperm antibodies. RESULTS: Sperm parameters were worse with seminal infection: 25 versus 84 million per milliliter for fertile men. Antioxidant activity, total alpha-tocopherol and retinol were reduced in leukocytospermia (P < .02, .01) and seminal infection (P < .01, .05) as compared to controls. Antisperm antibodies IL-2 and IL-8 were highly expressed, while IL-4 was low in men with leukocytospermia and bacteriospermia. Gram-negative organisms were more associated with expression of T-helper 1 cytokines than T-helper 2 cytokines. Antibiotic therapy significantly improved the sperm parameters, antioxidant activity and IL-4 but reduced IL-2 and IL-8 and had no effect on antisperm antibody titer. CONCLUSION: Antibiotic therapy improves sperm parameters by increasing antioxidant activity and IL-4 and by reducing IL-2 and IL-8. 相似文献
156.
We present recent developments in the area of glycosaminoglycans (GAGs) and their possible interaction with insulin-like growth factor-I (IGF-I). GAGs are constituents of proteoglycans, and the combination of a core protein and a specific GAG makes a unique proteoglycan with a precise developmental pattern and with the ability to bind growth factors. This process is apparently regulated by the moiety of the peripheral GAGs. The supplementation of GAGs promotes neuritogenesis in vitro and stimulates nerve regrowth and muscle reinnervation, an effect correlated with an increase in trophic factor mRNA expression. In the case of neonatal nerve lesion, there is in addition an enhanced motor neuron survival, accompanied by higher levels of IGF-I in plasma and denervated muscle. The neurotrophic and neuroregenerative effects of exogenous GAGs were also observed in motor neuron disease in the wobbler mouse. 相似文献
157.
BACKGROUND: Many studies have reported the increased expression of epidermal growth factor receptor (EGFR) in various human malignancies and its association with the biologic behavior of the tumors. METHODS: We performed an immunohistochemical analysis of the EGFR in 217 cases of human esophageal squamous cell carcinoma, 161 lymph node metastases and 23 foci of squamous dysplasias. The findings were correlated with clinicopathologic features, including the clinical outcome. Southern blot analysis was performed in 42 cases for the detection of DNA amplification of the EGFR gene and subsequently was correlated with EGFR immunoreactivity. RESULTS: Epidermal growth factor receptor overexpression was detected in 71% of primary tumors and 88% of lymph node metastases, as compared to nonpathologic adjacent esophageal epithelium. Statistically significant correlations were observed between EGFR overexpression and sex, age, histologic type, and the presence of invasion. Tumor staining was classified into two patterns, homogeneous and heterogeneous, based on the distribution of EGFR-positive cells. The immunostaining patterns of primary tumors had a statistically significant correlation with histologic type, the presence of adventitial invasion, histologic stage and lymph node metastasis. There was a tendency toward a worse prognosis for those patients with EGFR overexpression in the primary tumor. Greater than 90% of the foci of squamous dysplasia demonstrated homogeneous EGFR overexpression. DNA amplification of the EGFR was observed in 21% of primary tumors, and all demonstrated immunohistochemical overexpression. CONCLUSIONS: Immunohistochemical overexpression of the EGFR, which was more frequent than EGFR DNA amplification, appears to play an important role in biologic behavior of human esophageal squamous cell carcinomas. 相似文献
158.
159.
SM Dimitrijevi? U Humer M Shehadeh WJ Ryves NM Hassan FJ Evans 《Canadian Metallurgical Quarterly》1996,15(3):393-401
For the first time a normal-phase HPLC method using photodiode-array detection is described for the analysis and purification of phorbol esters. The use of the method is demonstrated with examples of 10 different tigliane and daphnane esters (TPA, DOPP, DOPPA, Sap A, Sap B, Sap C, Sap D, Thy A, Ro and Rx). Both analytical and semipreparative techniques were developed. The method has been used in the final purification of DOPP and Rx from plant extracts. The method can be employed in the areas of phytochemistry, biochemistry and pharmacology/toxicology, where small samples of the toxic materials are required for research. 相似文献
160.
N Fadlallah N Guy MA Teillet B Schuler NM Le Douarin R Naquet C Batini 《Canadian Metallurgical Quarterly》1995,675(1-2):55-66
The epileptic homozygotes of the Fayoumi strain of chickens (Fepi) are affected by photogenic reflex epilepsy with complete penetrance. Here we demonstrate that they are equally affected by audiogenic reflex epilepsy induced by intense sound stimulation. All the Fepi display sound-induced seizures from hatching to adulthood consisting of initial 'ictal arousal' and running fits usually followed by generalized clonico-tonic convulsions. A running fit is the preconvulsive motor symptom specifically induced by auditory stimulation while neck myoclonus is the preconvulsive motor symptom specifically induced by photic stimulation. The EEG interictal spikes and spike and waves are suppressed and replaced by a desynchronized trace during the seizures of both kinds. Viable neural chimeras were obtained by graft of embryonic brain vesicles from Fepi donors into normal chick embryos. Transfer of the complete audiogenic and photogenic phenotypes was obtained in chimeras resulting from embryonic substitution of both the prosencephalon and mesencephalon. The substitution of the prosencephalon alone resulted in transfer of interictal paroxysmal EEG activity accompanied by the sound and light-induced desynchronization and 'ictal arousal' with no motor seizures. Chimeras with embryonic substitution of the mesencephalon alone displayed running fits and convulsions induced by sound stimulation but only neck myoclonus following light stimulation. The conclusions are reached that: (i) the Fepi is a model of audiogenic and photogenic reflex epilepsy; (ii) in both types, the seizure initiator and the convulsion generator are localized in the brainstem, although reinforcement from telencephalic visual structures is needed to trigger photogenic generalized convulsions. 相似文献