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991.
A 79-year-old man presented with dilated cardiomyopathy and chronic atrial fibrillation. A DDD pacemaker was implanted due to sick sinus syndrome. His left ventricular ejection fraction was 23%. He was repeatedly admitted with congestive heart failure. Although cardiac resynchronization therapy was attempted, insertion of a pacing lead into the coronary sinus failed. Right ventricular bifocal pacing was done. The QRS width was shortened to 155 msec during bifocal pacing and 157 msec during right ventricular outflow pacing from 221 msec during right ventricular apical pacing. Heart failure was improved from New York Heart Association class III to II. Regional wall motion was assessed by strain of the myocardium. Bifocal pacing increased stroke volume due to improvement of longitudinal dyssynchrony of the septal and lateral walls. Bifocal pacing is effective for patients with severe congestive heart failure in whom biventricular pacing therapy has failed. Strain Doppler imaging is useful for the assessment of regional wall motion during cardiac pacing.  相似文献   
992.
A 61-year-old man was admitted to our clinic for a liver examination. Ultrasonography revealed multiple echo-rich lesions in both lobes. A laparoscopy showed a liver with an irregular surface, and a 3-mm-sized dark reddish lesion on the inferior surface of the right lobe. alpha-Fetoprotein and plasma protein induced by vitamin K absence or antagonist were normal. A liver biopsy specimen obtained from the small lesion by laparoscopy-guide showed a well-differentiated hepatocellular carcinoma with bile formation. Biopsy specimens obtained later from the 2 echo-rich lesions by ultrasonographic-guide were histologically similar to the lesion laparoscopically observed. Laparoscopic ethanol injection and percutaneous ethanol injection were performed as therapeutic procedures. Recurrence of hepatocellular carcinoma at the treated sites was not observed during the 6-year observation period. Thus, laparoscopy might play an important role in the early detection and treatment of hepatocellular carcinomas on the surface of the liver.  相似文献   
993.
Coagulopathy is still a frequent complication in the surgical treatment of acute aortic dissection. This study was designed to clarify the influence of acute aortic dissection on the clotting-fibrinolysis system and platelet function. From January 1993 to December 1994 21 patients with proven Stanford type B aortic dissection underwent a series of tests and procedures at our institution. There were 6 women and 15 men, aged 37–74 years (mean 62 years). All patients were admitted within 14 days of onset of dissection. No patient had complications requiring surgery and none died during the observation period. We observed a severe inflammatory reaction with activation of the clotting-fibrinolysis system immediately after onset of dissection. The platelet maximum aggregation rates were also decreased transiently after onset of the dissection. D-dimer values remained elevated throughout, the observation period. A rational approach to the surgical treatment of acute aortic dissection should involve coping with its activated clotting-fibrinolysis system and platelet dysfunction in addition to tissue friability.  相似文献   
994.
Our objective was to clarify the relationship between the serum levels of procollagen type I carboxyterminal propeptide (PICP) and the extent of skin sclerosis or pulmonary fibrosis in patients with systemic sclerosis (SSc). Thirty-eight SSc patients and 36 control subjects were examined for serum PICP levels using enzyme-linked immunosorbent assay. SSc patients were divided into two subgroups according to the grade of skin sclerosis. Mean PICP level in the SSc patients was significantly higher than that in the normal controls. In 53% of the SSc patients, the serum PICP levels were elevated more than 3 SD above the mean control value. The SSc patients with elevated serum PICP levels showed a high incidence of pulmonary fibrosis of diffuse skin sclerosis compared to those with normal PICP levels. Moreover, in 17 patients with pulmonary fibrosis there was an increase in the percentage of patients with elevated PICP levels in the group with diffuse SSc compared to that in the limited SSc group. Furthermore, there was a significant negative correlation between PICP levels and partial pressure of arterial oxygen levels (r=−0.744). We conclude that serum PICP levels may be a useful parameter for the evaluation of skin sclerosis and pulmonary fibrosis of SSc patients.  相似文献   
995.
We report a case of HLA-B52-positive Behçet disease accompanied by multiarterial lesions. A 24-year-old woman was suffering from sporadic high fever and recurrent oral and genital ulcers, and laboratory data revealed severe inflammation. A diagnosis of Behçet disease was made. Magnetic resonance angiography, ultrasound study, and computed tomographic angiography demonstrated multiarterial lesions that had caused no symptoms. These noninvasive examinations were extremely useful in evaluating asymptomatic early vascular lesions.  相似文献   
996.
OBJECTIVE: The purpose of the present study was to examine the following during radiofrequency ablation (RFA): (1) the risk of hemorrhage from intrapulmonary large vessels; (2) the risk of incomplete ablation of pulmonary tumors; and (3) the late effect on lung tissue. MATERIALS AND METHODS: A 17-gauge, cool-tip-type radiofrequency electrode was used. The damage to the vessels and bronchi was examined by the injection of a colored silicone rubber, a liquid compound that hardens after injection. To examine the risk of hemorrhage from intrapulmonary large vessels, RFA was conducted at eight sites near the central pulmonary vessels in two swine. To examine the risk of an incomplete ablation for pulmonary tumors, 10 pulmonary nodules were made from a gelatin mixture in another two swine and were treated by RFA. To examine the late effect on lung tissue, RFA was conducted on the peripheral lung in 10 rabbits, and then the ablated regions were examined on days 1, 7, 14, 21, and 28 after RFA. RESULTS: The use of colored silicone rubber enabled us to examine the intrapulmonary vessels and bronchi for opening and leakage. RFA did not damage the large intrapulmonary vessels, even when they were located within the ablated regions. Lung tissue surrounding the gelatin nodules was hardly ablated over its entire circumference. Six of 10 gelatin nodules (60%) showed nonablated areas on the peripheral edges of the nodules. From 21 days after RFA, the ablated rabbit lung formed noninfectious cavities by communicating with the surrounding bronchi. CONCLUSION: It was improbable for hemorrhage to occur even when RFA was conducted near the large intrapulmonary large vessels. Because an incomplete ablation that left tumor cells at the site of ablation could occur during surgery due to the difficulty of ablating the entire tumor circumference, CT scan-guided RFA would be preferable to a surgical approach for making a safe margin. Cavity formation can occur beginning 21 days after RFA, which should be carefully followed up in a clinical setting to identify infection, especially in immunocompromised patients.  相似文献   
997.
998.
999.
The near-infrared electronic endoscope for diagnosis of esophageal varices.   总被引:1,自引:0,他引:1  
We developed an electronic endoscope sensitive to light delivered by an infrared laser, which makes it possible to visualize submucosal vessels of the gastrointestinal tract. The system consists of a modified electronic endoscope and an image processing unit. A high output laser diode was chosen as the source of the infrared ray with a wavelength of 815 nm, an output of 200 milliwatts, and a band width of 30 nm. Using this instrument, esophageal varices were classified into three categories: venous dilation, dark spot, and diffuse dark area. The venous dilation and dark spot appearances correlated with early esophageal varices, which were rarely seen with visible light. On the other hand, the diffuse dark area appearance was considered to be a high risk sign of future bleeding. This system is useful not only for the early diagnosis of esophageal varices, but also for the localization of optimal puncture sites and the evaluation of the effect of sclerotherapy.  相似文献   
1000.
Prolactin (PRL) secretion is regulated by photoperiod in mammals and birds. In mammals, the pars tuberalis (PT) in the pituitary is involved in the regulation of photoperiodic regulation of PRL secretion. In birds, however, hypothalamic vasoactive intestinal peptide is implicated in PRL secretion, and physiological roles of the avian PT remain unknown. In the present study, we show that PRL secretion increases under long days and short days with a night interruptive schedule, both of which also cause gonadal growth in Japanese quail. We have also found Cry1 gene expression in the PT of Japanese quail. Cry1 expression was rhythmic under long and short photoperiods in the PT, and the peak was phase delayed under a lengthened photoperiod. Moreover, expression of Cry1 gene was induced by a light pulse but only when given during the photoinducible phase. In our previous study, we have shown rhythmic Per2 gene expression with a peak in the PT during the early day under various photoperiods. When taken together with the results from the present study, different phase relationships between Per2 and Cry1 in the Japanese quail PT under different photoperiods may decode photoperiodic information and regulate photoperiodic PRL secretion in a manner similar to that of mammals.  相似文献   
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