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91.
Electrophysiologic study was performed in 25 patients with tachycardia or bradycardia attacks. The coronary sinus (CS) and filtered bipolar esophageal electrograms were recorded simultaneously to compare the phase of atrial activations. During sinus rhythm and high right atrial pacing, the esophageal and proximal CS atrial activations were nearly simultaneous but earlier by 26 +/- 5 msec on the average than the distal CS atrial activations. During reciprocating tachycardia due to reentry using a left-side accessory atrioventricular pathway for retrograde conduction the esophageal and CS atrial activations occurred earlier than the low septal right atrial activation, so the esophageal lead can be used as a substitute for the CS lead to clarify the eccentric retrograde atrial activation sequence. By using the filtered bipolar esophageal lead, the interval from Q wave on the surface electrocardiogram to the first rapid deflection in the esophageal atrial activation (Q-AESO interval) was measured in 15 patients with supra-ventricular tachycardia. All patients with reciprocating tachycardia due to reentry using a left side accessory atrioventricular pathway had Q-AESO intervals between 100 to 130 msec and four of five patients with a right side accessory atrioventricular pathway for retrograde conduction had Q-AESO intervals between 130 to 150 msec. In contrast, all patients with reentry in the atrioventricular node had Q-AESO intervals between 30 to 60 msec. The esophageal lead is also of value in the prompt diagnosis of atrial flutter and ventricular tachycardia, since the esophageal electrograms readily reveal the relationship between atrial and ventricular activations. In conclusion, the filtered bipolar esophageal lead provides a non-invasive method for the quick diagnosis of various arrhythmias.  相似文献   
92.
OBJECTIVES: To evaluate whether the response to antiarrhythmic drug therapy in patients with paroxysmal atrial fibrillation affects the development of structural remodeling in the left atrium and ventricle. METHODS: This study included 230 patients (158 men and 72 women, mean age 67 +/- 11 years) in whom antiarrhythmic drug therapy was attempted for > or = 12 months to maintain sinus rhythm (mean follow-up period 45 +/- 27 months). The patients were divided into three groups according to the response to antiarrhythmic drug therapy: group A consisted of 78 patients without recurrence of atrial fibrillation, group B consisted of 87 patients with recurrence of atrial fibrillation and electrical and/or pharmacological cardioversion to restore sinus rhythm, and group C consisted of 65 patients with permanent conversion despite antiarrhythmic drug therapy. RESULTS: In group A, left atrial dimension (LAD), left ventricular end-diastolic dimension (LVDd), and left ventricular ejection fraction (LVEF) did not change after antiarrhythmic drug therapy. In group B, LAD increased significantly after antiarrhythmic drug therapy (from 32.6 +/- 6.4 to 36.0 +/- 6.5 mm, p < 0.01), Whereas either LVDd or LVEF did not change after antiarrhythmic drug therapy. In group C, LAD increased significantly after antiarrhythmic drug therapy (from 37.3 +/- 7.0 to 40.5 +/- 7.9 mm, p < 0.01) and LVEF was significantly reduced after antiarrhythmic drug therapy (from 69.4 +/- 6.2% to 66.5 +/- 8.9%, p < 0.05). LVDd did not change after antiarrhythmic drug therapy. The plasma concentration of human atrial natriuretic peptide during sinus rhythm at the initiation of antiarrhythmic drug therapy in group A (30.5 +/- 26.7 pg/ml) was significantly lower than those in group B (48.0 +/- 49.7 pg/ml) and group C (49.7 +/- 39.5 pg/ml). CONCLUSIONS: The development of structural remodeling in human myocardium can be prevented with antiarrhythmic drug therapy if sinus rhythm is maintained without recurrence of atrial fibrillation in patients with paroxysmal atrial fibrillation.  相似文献   
93.
Isolates from various clinical materials in 13 hospitals in Akita prefecture and their drug susceptibility were investigated by the Chemotherapy Research Committee of Akita Prefecture during the period from Dec., 1987 to Feb., 1988. The results were as follows: 1. The total number of isolates was 8,387, including Staphylococcus aureus (18.9%), Pseudomonas aeruginosa (10.9%), Staphylococcus epidermidis (7.3%) and Enterococcus faecalis (6.6%). S, aureus and P. aeruginosa were detected more frequently in the larger hospitals. 2. The detection frequency of S. aureus from the sputum, throat swab and pus exudate was also very high. There was a diversity in isolates from the urine and the frequency of Escherichia coli was low. More than half of the isolates from the blood were S. epidermidis and S. aureus. Many kinds of bacteria were detected from pleural fluid and ascites, but the isolate showed no particular tendency. 3. The susceptibility of S. aureus to oxacillin were variable in hospitals, and the susceptibility to cefazolin were even lower. Low susceptibility were also seen with norfloxacin. S. aureus showed the highest susceptibility to minocycline. The susceptibility was lower for inpatients than for outpatients. P. aeruginosa showed low susceptibility to cefsulodin. The number of ampicillin-resistant Haemophilus influenzae isolates tended to decrease. Enterobacter cloacae showed a low susceptibility for cephems. Serratia marcescens showed low susceptibility to many drugs. Based on the above results, we concluded that attention should be paid to S. aureus, P. aeruginosa and Enterobacter in clinical practice.  相似文献   
94.
A 62-year-old woman admitted for rectal carcinoma suffered from a post-operative bacterial infection. Oxy-imino-beta-lactams including cefotiam (CTM) and cefozopran (CZOP) were prescribed for this case, but the patient developed a wound abscess followed by peritonitis. She recovered from the bacterial infection after drainage and recurrent washing of the abscess. An ephemeral aggravation of infectious signs was observed just after creation of an artificial anus, and CZOP was again administered, and no evident bacterial infection occurred. The patient recovered, then was followed as an outpatient to date. A CAZ-resistant (MIC, > 16 micrograms/ml) E. coli was recovered from pus of her wound abscess. Since the CAZ-resistance decreased (MIC, 64 micrograms/ml-->0.13 microgram/ml) by the presence of clavulanate (CVA) in this isolate, this strain was speculated to be an extended spectrum beta-lactamase (ESBL) producer at an early stage of infection. A similar strain was also isolated from the feces. Therefore, we immediately took measures to block the nosocomial spread of this microorganism, and we succeeded in preventing a nosocomial outbreak of this strain. It was later confirmed by PCR analysis and DNA sequencing analysis that this CAZ-resistant E. coli strain produces an ESBL (SHV-5-2a = SHV-12). This is the first report of a case of infection with SHV-derived ESBL producing E. coli strain in Japan. We are concerned that further dissemination of this kind of microorganism might occur in the near future also in Japan, as it has been widely observed in European countries and the US. We believe that it will be very important to distinguish the type of beta-lactamases for rigorous bacterial infection control with the prudent use of antibiotics. In other words, we in Japan must recall that various gram-negative bacterial species that produce TEM-, SHV-derived ESBLs, Toho-1, AmpC, or IMP-1 are already widespread. Thus, we should take this fact into consideration when we do antibiotic susceptibility tentings and interpretation of the results for promotion of accurate chemotherapy.  相似文献   
95.
We investigated age-related changes in the ubiquitination of histones in mouse brains. By Western blot analysis using rabbit anti-ubiquitin antibodies, histone H2A and H2B were found to be the only proteins that are ubiquitinated in the acid-extractable nuclear proteins of both young (4-month-old) and senescent (29-month-old) mouse brains. The proportion of ubiquitinated histones was about 30% higher in senescent mice than in young ones. When total brain homogenates were analyzed similarly using somewhat different age groups of the animals, the proportion in the old animals was about 2-fold higher than that in the young.  相似文献   
96.
Anomalous coronary arteries are usually identified incidentally by angiography or autopsy, but some "malignant" coronary anomalies are associated with a high incidence of syncope, arrhythmia, myocardial infarction, and sudden death. So far, the pathogenesis of the coronary events in such cases has only been revealed by autopsy. In the present case report, a patient with anomalous origin of the right coronary artery from the left sinus of Valsalva developed acute myocardial infarction, and visualization of the anomaly and assessment of the culprit plaque in the artery were done by multidetector row computed tomography and intravascular ultrasound.  相似文献   
97.
We evaluated the effect of a mucoactive agent (-)-(R)-2-amino-3-(3-hydroxypropylthio) propionic acid (fudosteine), on airway inflammation using endotoxin- and antigen-induced models. Time courses of growth related oncogene/cytokine-induced neutrophil chemoattractant-1 (GRO/CINC-1) production, neutrophil migration and goblet cell hyperplasia were examined in endotoxin-induced rat airway inflammation. GRO/CINC-1 in bronchoalveolar lavage fluid (BALF) increased in response to intratracheal instillation of endotoxin and peaked within 4 h. Neutrophils in BALF and goblet cells on trachea peaked 24 and 96 h after endotoxin instillation, respectively. Fudosteine significantly inhibited increases in GRO/CINC-1 at 10-100 mg/kg, and neutrophils and goblet cells at 30 and 100 mg/kg. These results suggest that inflammatory events including neutrophil chemoattractant production and neutrophil migration play important roles for goblet cell hyperplasia in endotoxin-induced airway inflammation, and fudosteine inhibits goblet cell hyperplasia by inhibiting GRO/CINC-1 production and/or neutrophil migration. Furthermore, fudosteine (100 mg/kg) inhibited ovalbumin-induced eosinophil infiltration into BALF, suggesting it attenuates asthmatic inflammation.  相似文献   
98.
99.
A 25-year-old man with low cardiac risks underwent coronary arteriography because of chest pain at rest. His only risk factors for coronary artery disease was smoking. Both right and left coronary arteries were ectatic and the left anterior descending artery was obstructed. In the acetylcholine provocation test, the left circumflex coronary artery showed severe constriction. Thus, this patient was diagnosed as having a combination of variant angina and occlusive coronary artery disease.  相似文献   
100.
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