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1.
Infected descending aortic fistula   总被引:1,自引:0,他引:1  
Two patients, each with an infected descending thoracic aortic fistula, are described. The first patient had a postpneumonitic empyema. Thoracostomy tube drainage resulted in obliteration of the empyema cavity. Upon slight withdrawal of the tube, 49 days after its insertion, massive pulsating bleeding occurred through the sinus tract. The bleeding was controlled with manual pressure at the entry site of the chest tube, and the patient was operated upon immediately. A descending aortic defect, 3 cm long X 1.5 cm wide, at the site of the thoracostomy tube was primarily closed. Ten months after the surgical procedure, the patient has had no difficulty referable to her aortic erosion. In the second patient, 9 months after removal of the T-10 vertebra (which had a large cell tumor) and replacement of the vertebra with Dunn's metallic device, hemoptysis and left lower lobe consolidation developed. Aortography demonstrated a lobulated false aneurysm, 4 cm wide X 6 cm long, at the site of Dunn's device. A 16-mm graft was sutured end to side to the descending aorta just distal to the left subclavian artery and to the abdominal aorta below the renal arteries. The false aneurysm was then removed, the two ends of the aorta were sutured, and the stumps were covered with omental graft. Nine months after the repair the patient has had no difficulty referable to the aortic surgery.  相似文献   
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Lymphocyte subpopulations in a whole-blood sample can be detected by adapting mouse monoclonal antibodies (MAbs) and peroxidase (EC 1.11.1.7) labeling to a flow cytometer equipped with a tungsten-halogen light source and scatter/absorption optics (Technicon H6000). In the optimized cytochemical conditions each cell population generates a distinct, well-separated cluster, for accurate "thresholding" of the surface-antigen negative and positive lymphocyte populations in the presence of other leukocytes. After reaction with MAb, the erythrocytes are lysed, and the lymphocytes and other leukocytes are fixed. Biotinylated anti-mouse IgG, used as a bridge, amplifies the response from the avidin-peroxidase label. Granulocytes and monocytes, which have high endogenous peroxidase activity, and the labeled lymphocytes are stained in a specific amount of hydrogen peroxide plus 4-chloro-1-naphthol in 4-(2-hydroxyethyl)-1-piperazine-ethanesulfonic acid buffer. Accuracy and precision are equivalent to those of flow cytometers that measure immunofluorescence (e.g., Ortho Spectrum III), as demonstrated with OKT3, OKT4, OKT8, OKT11, and Leu 12 MAbs.  相似文献   
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Background: Impulse oscillometry (IOS) has previously been proposed to provide greater sensitivity than spirometry when employed with indirect bronchoprovocation testing for the diagnosis of airway dysfunction in athletes. However, this recommendation is based on a highly selected population of symptomatic patients. Objective: To compare IOS, spirometry and respiratory symptoms following indirect bronchoprovocation in a screened cohort of athletes. Methods: One hundred and one recreational athletes were recruited. Respiratory symptoms were assessed via the Dyspnoea-12 questionnaire. Spirometry and IOS were performed pre and post a eucapnic voluntary hyperpnoea (EVH) challenge. Results: Ninety-four athletes completed the study. Sixteen athletes (17%) were positive for airway dysfunction based on spirometry (i.e. ≥10% fall in FEV1) and 17 athletes (18%) based on IOS (i.e. ≥50% increase in R5). Only nine athletes (10%) met both diagnostic thresholds. A poor relationship was observed between respiratory symptoms (i.e. Dyspnoea-12 score) and all spirometry and IOS variables. A direct relationship was observed between percentage change in R5 (r?=?0.65), Z5 (r?=?0.68), RF (r?=?0.65), AX (r?=?0.69) and the maximum fall in FEV1 (ΔFEV1max; p?<?0.001). A weak relationship was observed between R20 (r?=?0.27), X5 (r?=?0.37) and ΔFEV1max (p?<?0.01). Conclusion: Impulse oscillometry and spirometry do not concur precisely following indirect bronchoprovocation. However, IOS detects additional cases of airway dysfunction in athletes and therefore may provide diagnostic value in this population. Further work is required to establish diagnostic thresholds and fully determine the place of IOS in screening athletes for airway dysfunction.  相似文献   
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The rate of suicide in the United States among prepubertal children and young adolescents had increased by 120% from 1980 to 1992. From 1992 to the present the rate has decreased slightly by 33%. We address a brief review of the most relevant findings in literature that are related to the risk of suicide. Although the most reported findings were child mood disorder, any type of family distress and family history of suicide attempts, the severity of those does not seem to increase the risk of suicide. However, there were other environmental factors that may influence the risk of suicide, such as the access to firearms. It is critical to detect risk factors and triggers in prepubertal populations in order to reduce the incidence of suicide in this age group and older age groups.  相似文献   
8.
Tick paralysis is an acute, progressive, and potentially fatal muscle paralysis secondary to a toxin secreted by a pregnant tick during a bite. Although tick bites can occur anywhere on the body, ticks are frequently overlooked on the scalp because of overlying hair. Children with acute neurologic symptoms frequently undergo MR scanning that may incidentally reveal the offending tick. Timely identification and removal of the tick leads to rapid recovery from tick paralysis. We report the MRI findings at 1.5 T of tick paralysis with an attached tick.  相似文献   
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OBJECTIVE: The endothelium-derived vasoconstrictor endothelin-1 is increased after cardiopulmonary bypass in children with congenital heart defects. This study determines whether antioxidant therapy with Salvia miltiorrhiza injection, an herb extract containing phenolic compounds, prevents the postoperative increase of endothelin-1. The relationship between endothelin-1 and the endothelium-derived prostacyclin (prostaglandin I2) and thromboxane A2 postoperatively is also investigated. METHODS: Twenty children with congenital heart defects and pulmonary hypertension were randomly assigned to group A (placebo control, n=10) or B (200 mg/kg Salvia miltiorrhiza intravenously after anesthesia induction and at the time of rewarming, respectively; n =10) before cardiac surgery. Central venous blood samples were taken before operation (T(0)), 10 (T(1)) and 30 minutes (T(2)) after starting cardiopulmonary bypass, 10 (T(3)) and 30 minutes (T(4)) after aortic declamping, and 30 minutes (T(5)) and 24 hours (T(6)) after termination of cardiopulmonary bypass. Plasma lipid peroxidation product malondialdehyde, myocardial specific creatine kinase-MB activity, thromboxane B2, and 6-keto-prostaglandin F(1 alpha) (stable metabolites of thromboxane A2 and prostaglandin I2) were measured. RESULTS: Malondialdehyde increased significantly at T(1) in group A and remained significantly higher than in group B thereafter (P <.05). Malondialdehyde in group B did not significantly increase over time. At T(5), plasma creatine kinase-MB, thromboxane B2, and endothelin-1 in group B were lower than in group A (P <.05); malondialdehyde correlated significantly with creatine kinase-MB (r = 0.71, P =.0005). At T(6), endothelin-1 negatively correlated with the 6-keto-prostaglandin F(1 alpha)/thromboxane B2 ratio (r = -0.64, P =.0025). CONCLUSION: Antioxidant therapy reduces myocardial damage and attenuates postoperative vasoactive mediator imbalance.  相似文献   
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