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11.
Carbon fibers with fibrin glue were used as electrodes for diaphragm pacing. The electrodes were applied to three mongrel dogs and the effectiveness was tested. The carbon leads were glued to phrenic nerves by means of the fibrinogen and thrombin bilaterally. The tidal volumes and threshold current level for stimulation were measured at various time up to 9 weeks after implantation. Effective contraction of diaphragm were observed for 9 weeks. By using this electrode, the exfoliation of the nerve is not necessary, the nerve can be maintained in an intact state, and the risk of the implanting operation can be minimized.  相似文献   
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To determine the clinical significance of regional left ventricular asynergy in patients with impending myocardial infarction, we recorded two-dimensional echocardiograms (2DE) serially and performed coronary angiography immediately after the hospital admission in nine patients with initial impending infarction and their last anginal attacks were within 48 hours. Left ventricular asynergy on the first 2DE was observed in six of nine patients during symptom-free periods (Group A: LV asynergy group). Five of the six patients had significant coronary artery lesions (greater than or equal to 75% stenosis) in at least one major coronary artery. Intracoronary filling defects were detected in four of the five patients. Another three patients without asynergy (Group B) had significant fixed stenosis. Coronary artery spasm was observed in two patients during coronary angiography, but no patient had intracoronary filling defects. Intracoronary nitroglycerin (0.1-0.3 mg) reduced the severity of coronary artery narrowing in two patients. In addition, urokinase (240,000-480,000 IU) via the corresponding vessel (PTCR) in the remaining seven patients resulted in reduction in the severity of coronary artery stenosis in four patients, but not in the remaining three patients. Left ventricular wall movement in the asynergy group improved rapidly and no asynergy was observed by the seventh hospital day in five of the six patients. Successful PTCR treatment resulted in improvement of left ventricular wall movement. No asynergy was found in the non-asynergy group throughout their hospitalizations. These findings indicated that abnormal left ventricular wall movement is found in patients with impending myocardial infarction, even during symptom-free periods, but the wall movement gradually improves. The 2DE observations are useful for estimating the clinical status and for planning precise therapy for impending myocardial infarction.  相似文献   
14.
The aim of this study was to investigate whether the metabolic syndrome (MS) was associated with an elevated level of C-reactive protein (CRP) and increased arterial stiffness, and to clarify whether combined MS and CRP data had a stronger relation to arterial stiffness than did MS data alone. Brachial-ankle pulse wave velocity (baPWV), CRP, and conventional risk factors were evaluated in 3,412 men and 854 women. Adjusted mean values of baPWV in men with 0, 1, 2, and > or = 3 components were 1,309, 1,372, 1,422, and 1,462 cm/s, respectively (p for trend <0.001). Adjusted mean values of baPWV in women with 0, 1, 2, and > or =3 components were 1,212, 1,292, 1,357, and 1,391 cm/s, respectively (p for trend <0.001). Adjusted geometric mean concentrations of CRP in men with 0, 1, 2, and > or = 3 components were 0.036, 0.049, 0.059, and 0.076 mg/dI, respectively (p for trend <0.001). Adjusted geometric mean concentrations of CRP in women with 0, 1, 2, and > or = 3 components were 0.023, 0.030, 0.057, and 0.077 mg/dI, respectively (p for trend <0.001). In analyses of adjusted mean values of baPWV according to the number of MS components and according to CRP levels within or without top quartile levels, the p value for the trend was significant (<0.001) in both men and women but, in post hoc analyses, comparing high and low CRP levels in each MS component-number group, no significant difference was found. These results suggest that, for prediction of increased arterial stiffness, combining MS and CRP data has little additive effect compared to the use of MS data alone.  相似文献   
15.
Oxidative stress is implicated in the pathogenesis of various cardiovascular diseases. We have shown that in Wistar rats with a suprarenal aortic constriction (AC), pressure overload-induced transient perivascular inflammation (monocyte chemoattractant protein-1 [MCP-1] induction and macrophage accumulation) in the early phase is the determinant of reactive myocardial fibrosis and resultant diastolic dysfunction in the late phase. Thus, we investigated the role of reactive oxygen species production in cardiac remodeling in AC rats. Superoxide production and the footprint of lipid peroxidation were assessed using dihydroethidium staining and immunohistostaining against 4-hydroxy-2-nonenal (4-HNE), respectively. In sham rats, dihydroethidium and 4-HNE signals were scarcely found in the heart. At day 3, AC rats showed dihydroethidium signals mainly in the intramyocardial arterial wall, whereas modest 4-HNE staining was observed diffusely in the myocardium. These signals declined to lower levels by day 14 despite sustained hypertension. Chronic administration of a subdepressor dose of an angiotensin II type 1 receptor blocker candesartan reduced the pressure overload-induced dihydroethidium and 4-HNE signals at day 3. Moreover, candesartan decreased MCP-1 induction and macrophage infiltration at day 3 and prevented myocardial fibrosis at day 14, without affecting left ventricle and myocyte hypertrophy. In conclusion, acute pressure overload induced self-limited superoxide production mainly in the vascular wall. The reactive oxygen species production would contribute to the perivascular inflammation and subsequent myocardial fibrosis. Angiotensin II was suggested to have a pressure-independent effect on the reactive oxygen species production.  相似文献   
16.
We report a case of aspergillosis in the subdural space and frontal lobe in an 83-year-old man. The clinical course simulated that of a brain tumor. The source for the infection was considered to be the previous burr-hole surgery for chronic subdural hematoma, which was performed 2.5 years before the onset of symptoms. The patient was treated by removal of the abscess and granuloma. The clinical features and treatment of aspergillosis after neurosurgical procedures are discussed.  相似文献   
17.
In 97 neonates receiving total parenteral nutrition in the postoperative period, clinical assessment was made for a newly devised amino acid solution (PF-I-III) from the standpoint of plasma amino acid profile and nutritional effect. These amino acid solutions prepared are characterized by the high concentration of branched-chain amino acids up to 40%, increased arginine and decreased glycine, phenylalanine and methionine as compared with commercially available solutions. In the PF group, each amino acid was kept within the range of standard value. Correlation between plasma amino acid profiles and the dose of each amino acid administered was obtained, from which minimum, standard, and maximum doses for each amino acid was determined. Based on these values, we proposed new formula for neonates which elicits no abnormal plasma amino acid pattern even when amino acids are administered at the dosage level of 1.5-2.5 g/kg/day.  相似文献   
18.
Venous drainage of a musculocutaneous graft was shown to be of importance for the prevention of necrosis and successful graft take. An experimental model was provided in which the iliolumbar veins were used as draining veins in creating musculocutaneous grafts 4 X 3 cm and 4 X 6 cm in size. In the study, it was demonstrated that necrosis could be prevented by preserving draining veins. The number and size of these veins were of some significance in the survival of the grafts.  相似文献   
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20.
De novo renal cell carcinoma in a renal allograft is rare and has special implications in renal transplant recipients. We describe a patient with a renal allograft who developed a de novo renal cell carcinoma in the functioning renal allograft 258 months after transplantation. The patient underwent enucleation of the tumor because preoperative MRI showed it was well-encapsulated. A DNA banding study showed that the tumor originated from the donor. Indications for conservative renal surgery in renal cell carcinoma have been increasing. Accordingly, 1 option in the treatment of de novo renal cell carcinoma in a functioning renal allograft is enucleation as a method of nephron sparing surgery.  相似文献   
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