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11.
Adrenoreceptor blockade has been used to separate the actions of elevated blood pressure, angiotensin II, and catecholamines on the coronary vasculature and myocardium of rats. Twenty-two male Wistar-Kyoto rats received phentolamine (an alpha-receptor blocker, 10 mg/kg body weight) and/or propranolol (a beta-receptor blocker, 1 mg/kg body weight) followed by an infusion for 2 hours of angiotensin amide (1.7 micrograms/min/kg) or saline. Sections of left ventricle were examined by light and electron microscopy. Blood pressure was elevated only in animals receiving angiotensin II with or without propranolol. Epicardial arteries were devoid of lesions in all animals. Small intramural arteries and arterioles in the hypertensive animals exhibited vasoconstriction, endothelial cell vacuolization with bleb formation, and medial smooth muscle cell fragmentation and necrosis. Foci of irreversible ischemic or anoxic myocardial injury consisting of contraction zones and bands and translocated mitochondria with granular matrix densities were seen in angiotensin-infused animals. Similar but less severe myocardial changes were found in the animals pretreated with propranolol. Vascular lesions were also seen in animals receiving phentolamine, propranolol, and angiotensin II; but myocardial alterations consisted solely of areas with contraction zones. Vascular but not myocardial lesions were observed in animals that received angiotensin II and phentolamine. It is concluded that angiotensin II can produce vascular injury in the absence of elevated systemic blood pressure or catecholamine effects. In contrast, irreversible myocardial injury seems to depend upon the increased pressure and/or coronary artery vasoconstriction associated with angiotensin administration.  相似文献   
12.
Juvenile xanthogranuloma. Clinical and pathologic characterization   总被引:2,自引:0,他引:2  
The changing name of the juvenile xanthogranuloma bears witness to the evolution of knowledge and experience of its varied clinical and histologic presentations. This study characterizes the clinical, microscopic, and some immunohistochemical features of 34 cases. The salient clinical findings include a bimodal age distribution inclusive of adults, a male:female ratio of 4:1, occasional multiplicity of lesions (20%), and common presentation in the cephalad area. Histologic findings include varied architectural patterns, cellular participation in various proportions by foamy histiocytes, epithelioid monocytes, lymphocytes, plasma cells, eosinophils, Touton giant cells, and spindle cells of two forms (dendritic and fusiform). S100-positive dendritic cells comprised a minor, but important, component at expansion zones. The significance of these findings is described.  相似文献   
13.
We have shown previously that cells comprising the cutaneous infiltrates of histiocytes X (HXCs), like Langerhans cells (LCs), react with monoclonal anti-T6 antibody. HXCs also react with anti-T4/4b and anti-Ia-like antibodies. To further define the patterns of antibody reactivity in HXCs, we performed immunoelectron microscopy on two clear-cut cases of histiocytosis X using the immunoperoxidase technique. The reaction product of diaminobenzidine, indicating anti-T6 antibody reactivity, was easily detected along cell membranes of HXCs and at sites of possible endocytosis. Anti-T4/4b and anti-Ia antibodies had less cell membrane reactivity. Computerized image analysis aided in discriminating the patterns of anti-T6 antibody in HXCs and from LCs and confirmed that anti-T6 antibody staining was the most intense of the antibodies evaluated. These findings (1) document antigenic similarities and differences between HXCs and LCs on an ultrastructural level, (2) add support to the concept that HXCs are abnormal proliferations of LCs, and (3) demonstrate the association of the cell surface antigen, T6, with apparent endocytotic activity.  相似文献   
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15.
BACKGROUND: A total of 25 patients with tetralogy of Fallot and an important coronary artery crossing the right ventricular outflow tract underwent complete repair without use of an extracardiac conduit between January 1990 and December 1994. Repair was exclusively done by the transatrial or transatrial-transpulmonary approach. Age of these patients ranged from 1 to 12 years (mean 3.6 years). Three of the patients had already received a systemic to pulmonary artery shunt. METHODS: All patients reporting for follow-up (n = 18) were subjected to transthoracic echocardiography and, if required, cardiac catheterization and angiography. Right ventricle to pulmonary artery gradients were noted preoperatively, at discharge following repair and at follow-up study. RESULTS: Mean follow-up was 40.6 months (24 to 62 months). Mean early postoperative gradient was 23.5+/-13.4 mm Hg and 4 patients had significant (> 30 mm Hg) gradients. Mean late postoperative gradient was 20.6+/-12.4 mmHg and 2 patients had gradients greater than 30 mmHg. All the patients were in New York Heart Association functional class I at the time of last follow-up. CONCLUSIONS: Acceptable gradients across the right ventricular outflow tract are achievable following repair of tetralogy of Fallot in the presence of anomalous coronary artery across the right ventricular outflow tract using the transatrial or transatrial-transpulmonary approach. Most gradients were found not to vary significantly on subsequent follow-up.  相似文献   
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17.

Purpose

Various strategies have been proposed to reduce discomfort of pain after rocuronium injection. These studies have shown pretreatment of drugs such as fentanyl and lidocaine to be effective. In a prospective randomized study, we evaluated whether pretreatment with local warming at injection site using an air-warming device could effectively alleviate pain induced by rocuronium.

Methods

Ninety patients undergoing spinal surgeries were randomly divided into two groups: group C (control) and group T (treatment). Patients in group T were subjected to warming at 40°C for 1 min prior to injecting 1 ml (10 mg) of rocuronium at the site of venous access. Patients were then assessed for any discomfort and to quantify their discomfort on a 5-point scale.

Results

Age, sex, and weight were comparable between the two groups. Pain on rocuronium administration was reported by 88.9% patient in group C versus 66.7% in group T (p < 0.05). Severe pain was significantly less in group T (35.6% vs. 8.9%).

Conclusion

Application of warmth over the vascular access prior to rocuronium administration effectively reduces injection-related pain.  相似文献   
18.
Spontaneous non-traumatic renal hemorrhage known as Wunderlich's syndrome is known to occur in renal angiomyolipoma and may be the first manifestation of the disease. Angiomyolipomas in tuberous sclerosis are usually bilateral and multicentric. A 25yr old female, a case of Tuberous sclerosis with bilateral renal angiomyolipomas presented with right loin pain of increasing severity. On evaluation she had acute abdomen with increasing abdominal distension. Investigations revealed large right perinephric hematoma with bilateral renal angiomyolipomas. Exploratory laparotomy and right nephrectomy was done. Spontaneous hemorrhage in renal angiomyolipoma in a case of tuberous sclerosis and management are discussed.  相似文献   
19.

Objective:

To compare the results of endoscopic carpal tunnel release (CTR) with open CTR in patients with idiopathic Carpal tunnel syndrome (CTS).

Materials and Methods:

Seventy-one patients with CTS were enrolled in a prospective randomized study from May 2003 to December 2005. All patients had clinical signs or symptoms and electro-diagnostic findings consistent with carpal tunnel syndrome and had not responded to nonoperative management. Sixty-one cases were available for follow-up. Endoscopic CTR was performed in 30 CTS patients and open CTR was performed in 31 wrists (30 patients). Various parameters were evaluated, including each patient''s symptom amelioration, complications, operation time, time needed to resume normal lifestyle and the frequency of revision surgery. All the patients were followed up for six months.

Results:

During the initial months after surgery, the patients treated with the endoscopic method were better symptomatically and functionally. Local wound problems in terms of scarring or scar tenderness were significantly more pronounced in patients undergoing open CTR compared to patients undergoing endoscopic CTR. Average delay to return to normal activity was appreciably less in group undergoing endoscopic CTR. No significant difference was observed between the endoscopic CTR group and open CTR group in regard to symptom amelioration, electromyographic testing and complications at the end of six months.

Conclusion:

Short-term results were better with the endoscopic method as there was no scar tenderness. Results at six months were comparable in both groups.  相似文献   
20.
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