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51.
DA Taylor 《Environmental health perspectives》2002,110(9):A512-A513
52.
The tensor fascia lata myocutaneous flap provides a reliable autogenous building block for anatomical lower abdominal wall reconstruction. Preservation of innervation allows maintenance of voluntary motor control and protective sensation. The excellent blood supply of this flap is particularly helpful in reconstructing previously irradiated areas. A one-stage repair is possible, leaving minimal secondary defect. We describe 4 patients illustrating the uses and versatilty of this flap. Anatomy, operative procedures, and indications for delay are also discussed. 相似文献
53.
54.
Rabbits treated with benzo(a)pyrene developed cardiac arrhythmias when exposed by inhalation to 8100 ppm trichloroethylene or 15000 ppm halothane to a greater extent and at lower doses of epinephrine challenge than did controls. Benzo(a)pyrene and 3-methylcholanthrene both increased the metabolism of trichloroethylene, but 3-methylcholanthrene did not increase its cardiotoxic effect. The basis of the arrythmogenic action of benzo(a)pyrene appears to be unrelated to its ability to induce xenobiotic metabolism. 相似文献
55.
Conventional teaching states that the spiral of Tillaux marks the location of the ora serrata. On literature review, no source for this was found. This study explores this anatomic relationship. In 20 cadaver eyes, narrow-gauge needles were placed penetrating the center of each rectus muscle insertion, and distance to the ora was measured. Insertions ranged from 2.25 mm posterior to 2.25 mm anterior to the ora, with 90% within 1 mm of it. In ten eyes, distance from the edge of insertion also was measured. Results indicate that the centers of rectus insertions, especially the lateral rectus, approximately overlie the ora, with the edges of the insertions more posterior and variable. 相似文献
56.
Respiratory muscle weakness is an uncommon cause of chronic respiratory failure and a rare cause of cor pulmonale. The problem may not be apparent unless specific physical signs are sought or appropriate investigations performed. We present three patients who presented diagnostic difficulty for prolonged periods until the presence of respiratory muscle weakness was considered. Once the diagnosis was established treatment with nocturnal nasal intermittent positive pressure ventilation produced a dramatic improvement in symptoms and allowed a return to a near normal lifestyle. 相似文献
57.
A Gustavsson J Eskilsson T Landberg H Larusdottir G Svahn-Tapper T White P Wollmer 《Annals of oncology》1992,3(6):455-461
Twenty-five patients (21-45 years old) treated for Hodgkin's disease with mantle radiotherapy but no chemotherapy underwent chest radiography and pulmonary testing with spirometry, pulmonary mechanics and exercise test combined with arterial blood gas analysis, lung scintigraphy, assessment of pulmonary artery pressure with Doppler cardiography and vector ECG 10-20 years after treatment. The doses to mediastinum ranged from 35-43 (mean 40) Gy given in 26 fractions with the split-course technique. Radiographic signs of slight to moderate pulmonary fibrosis were seen in 18 patients. Minor restrictive ventilatory defects were found with decreased VC, TLC and lung compliance and increased maximal elastic recoil. Little evidence of airflow obstruction was found. Exercise capacity was decreased in three individuals but the mean value for the study group as a whole was normal. Arterial PO2 at maximum exercise was reduced but no patient had diminished hemoglobin saturation. Lung scintigraphy showed defects in 21 patients, mostly consisting of slight abnormalities at the lung periphery and apices. The perfusion seemed to be more affected than the ventilation, suggesting primary vascular lesions. Twelve patients showed signs of right ventricular hypertrophy in vector ECG and four of these had systolic pulmonary artery pressure greater than or equal to 30 mm Hg. The observed abnormalities were mostly of a minor degree and few clinically significant long-term effects of mantle radiotherapy on pulmonary function were observed. 相似文献
58.
59.
Reperfusion increases neutrophils and leukotriene B4 receptor binding in rat focal ischemia. 总被引:19,自引:0,他引:19
F C Barone D B Schmidt L M Hillegass W J Price R F White G Z Feuerstein R K Clark E V Lee D E Griswold H M Sarau 《Stroke; a journal of cerebral circulation》1992,23(9):1337-47; discussion 1347-8
BACKGROUND AND PURPOSE: Neutrophils are critically involved with ischemia and reperfusion injury in many tissues but have not been studied under conditions of reperfusion after focal cerebral ischemia. The present studies were conducted to confirm our previous observations quantifying neutrophils in rat permanent focal stroke using a myeloperoxidase activity assay and to extend them to transient ischemia with reperfusion. In addition, leukotriene B4 receptor binding in ischemic tissue was evaluated as a potential marker for inflammatory cell infiltration. METHODS: Histological, enzymatic, and receptor binding techniques were used to evaluate neutrophil infiltration and receptor binding in infarcted cortical tissue 24 hours after permanent middle cerebral artery occlusion (n = 25) or temporary occlusion for 80 (n = 12) or 160 (n = 22) minutes followed by reperfusion for 24 hours in spontaneously hypertensive rats. RESULTS: Sham surgery (n = 26) produced no changes in any parameter measured. After permanent middle cerebral artery occlusion, neutrophil accumulation was observed histologically, but the infiltration was moderate and typically within and adjacent to blood vessels bordering the infarcted cortex. After temporary middle cerebral artery occlusion with reperfusion, marked neutrophil infiltration was observed throughout the infarcted cortex. Myeloperoxidase activity was increased (p less than 0.05) after permanent occlusion and to a greater extent after temporary occlusion with reperfusion. Myeloperoxidase activity (units per gram wet weight) in ischemic cortex was increased over that in nonischemic (control) cortex 32.2-fold, 54.6-fold, and 92.1-fold for permanent occlusion and 80 and 160 minutes of temporary occlusion with reperfusion, respectively (p less than 0.05). Sham surgery produced no changes in myeloperoxidase activity. Leukotriene B4 receptor binding also was increased (p less than 0.05) after focal ischemia and paralleled the increases in myeloperoxidase activity. Ischemic cortex-specific receptor binding (femtomoles per milligram protein) was 3.87 +/- 0.63 in sham-operated rats and 4.57 +/- 0.98, 8.98 +/- 1.11, and 11.12 +/- 1.63 for rats subjected to permanent occlusion and 80 and 160 minutes of temporary occlusion with reperfusion, respectively (all p less than 0.05 different from sham-operated). Cortical myeloperoxidase activity was significantly correlated with the degree of cortical leukotriene B4 receptor binding (r = 0.66 and r = 0.79 in two different studies, p less than 0.01). CONCLUSION: These data indicate that neutrophils are involved in focal ischemia and that there is a dramatic accumulation of neutrophils in infarcted tissue during reperfusion that can be quantified using the myeloperoxidase activity assay. Leukotriene B4 receptor binding increases in infarcted tissue in a parallel manner, which suggests that the increased leukotriene B4 binding is to receptors located on the accumulating neutrophils. 相似文献
60.
D M Portz T E Elkins R White J Warren S Adadevoh J Randolph 《International journal of fertility》1991,36(1):39-42
Intraperitoneal superoxide dismutase (SOD) and catalase were used to block the toxic effects of superoxide anion (O2) and hydrogen peroxide (H2O2), associated with the production of endometriosis and inflammation in a rabbit model. In a two-part animal study, the combined instillation of SOD and catalase significantly reduced the formation of intraperitoneal adhesions at endometriosis sites. 相似文献