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51.
A patient survived a stab wound of the heart, and an aneurysm of the left anterior descending coronary artery developed with a fistulous communication into the left ventricle and a postinfarction ventricular aneurysm. All lesions were successfully repaired by surgery 4 years later. Preoperatively the patient suffered from angina pectoris presumably due to a coronary arterial “steal syndrome” and recurrent myocardial infarction presumably due to coronary embolism from thrombi formed within the coronary aneurysm. The combination of a coronary arterial aneurysm and a coronary arterial-left ventricular fistula produced a diastolic murmur that disappeared after surgery. 相似文献
52.
Thymuses from female (New Zealand black x New Zealand white)F1 [( NZB x NZW]F1), New Zealand black, and New Zealand white mice of different ages were examined by immunohistochemical and flow cytometric analysis. Two-and-a-half-month-old (NZB x NZW)F1 mice showed infiltration of the thymus with B cells, and by 6-8 months of age, showed a disruption of the entire medullary area. More than 80% of the thymic B cells had the phenotypic characteristics of conventional B cells (IgM+, IgD+, Ly-1-). Total lymphoid irradiation induced a marked depletion of medullary B cells and a restoration of the thymic architecture. 相似文献
53.
Hydrogen peroxide generation by mitochondria isolated from regionally ischemic and nonischemic dog myocardium 总被引:1,自引:0,他引:1
Summary We occluded the left anterior descending coronary artery of anesthetized, open-chest dogs, for 1 or 2 h. Some hearts were reperfused for 1 h after 1 h of ischemia. We isolated mitochondria from the central ischemic zone (CIZ) and a surrounding nonischemic zone (NIZ) of the left ventricle, and assayed H2O2 production using a horseradish peroxidase-dual wavelength spectrophotometric technique. Mitochondria, studied in the absence of exogenous respiratory chain inhibitors, generated H2O2 during State 4 respiration with succinate as the substrate. NIZ mitochondria in all groups produced ca. 1.5 nmols H2O2/min/mg protein (no significant differences between groups). The State 4 O2 consumption rates of NIZ mitochondria from hearts subjected to 1 h ischemia plus reperfusion, or 2 h of ischemia (ca. 30 nmols/min/mg) were significantly higher than that of NIZ mitochondria of hearts subjected to only 1 h of ischemia (23 nmols/min/mg). Thus, the ratio between H2O2 produced and State 4 O2 consumption fell from 6.5% to 5%. Mitochondria from all CIZ samples had State 4 O2 consumption rates that were not different from corresponding NIZ values. However CIZ mitochondria of hearts subjected to 1 h ischemia without reperfusion produced less H2O2 (1.1±0.1 nmols/min/mg), and had a slightly reduced H2O2/O2 ratio (4.4±0.7%), compared with their NIZ samples (1.5±0.1 nmols/min/mg; 5.3%). Reperfusion after 1 h of ischemia abolished these regional differences. The CIZ mitochondria from hearts subjected to 2 h ischemia produced only 0.75±0.22 nmols H2O2/min/mg (2.5% of State 4 O2 consumption). These values were 50% of corresponding NIZ values, and were significantly less than for any other group or tissue region. If similar phenomena occur in conscious animals subjected to incomplete regional ischemia, especially of relatively brief duration or if accompanied by reduced intracellular defenses against oxidants such as H2O2, they suggest that mitochondria persist as H2O2 sources and so may contribute to the oxidant load and myocardial dysfunction.Supported by grants from the National Institutes of Health (HL-29499) and from the American Heart Association of Michigan 相似文献
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55.
Klimberg VS Kepple J Shafirstein G Adkins L Henry-Tillman R Youssef E Brito J Talley L Korourian S 《Annals of surgical oncology》2006,13(11):1422-1433
Introduction Excision followed by RFA (eRFA) may allow improved cosmesis while ensuring negative margins in patients with breast cancer. This technique utilizes heat to create an additional tumor-free zone around the lumpectomy cavity. We hypothesized that eRFA will decrease the need for re-excision of inadequate margins.Methods Between July 2002 and January 2005, we conducted a multiphase trial of RFA of prophylactic mastectomy specimens and of women desiring lumpectomy. In both models, a lumpectomy was performed, the RFA probe was deployed 1 cm circumferentially into the walls of the lumpectomy cavity and maintained at 100°C for 15 min. Whole mount slides were used to measure the zone of ablation for ex vivo specimens. Hematoxylin and eosin staining of in vivo lumpectomy margins <3 mm was considered inadequate.Results Nineteen prophylactic mastectomy ablations revealed a consistent perimeter of ablation. Forty-one patients (mean age 63 ± 14 years) had an average tumor size of 1.6 ± 1.5 cm underwent in vivo eRFA, and 25% had inadequate margins: one focally positive, one <2 mm, eight <1 mm and one grossly positive. Only the grossly positive margin was re-excised. Overall complication rate of in vivo ablations was 7.5%. Twenty-four of 41 patients did not have post-eRFA XRT. No in-site local recurrences have occurred during a median follow-up of 24 months (12–45 months). Two patients have occurred elsewhere.Conclusions The ex vivo ablation model reliably created a 5–10 mm perimeter of ablation. In vivo, this zone reduced the need for re-excision for inadequate margins by 91% (10/11). Short-term follow-up suggests that eRFA could reduce re-excision surgery and local recurrence. 相似文献
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57.
Storch EA Murphy TK Geffken GR Mann G Adkins J Merlo LJ Duke D Munson M Swaine Z Goodman WK 《Journal of the American Academy of Child and Adolescent Psychiatry》2006,45(10):1171-1178
OBJECTIVE: To provide preliminary estimates of the effectiveness of cognitive-behavioral therapy (CBT) in treating pediatric obsessive-compulsive disorder (OCD) of the pediatric autoimmune neuropsychiatric disorders associated with streptococcus (PANDAS) subtype. METHOD: Seven children with OCD of the PANDAS subtype (range 9-13 years) were treated in a 3-week intensive CBT program conducted at a university clinic. Six of seven children were taking selective serotonin reuptake inhibitor medication(s) upon presentation. Assessments were conducted at four time points: baseline, pretreatment approximately 4 weeks later, posttreatment, and 3-month follow-up. Raters were blind to the nature of the study treatment. RESULTS: Six of seven participants were classified as treatment responders (much or very much improved) at posttreatment, and three of six remained responders at follow-up. Clinician severity ratings, as measured by the Children's Yale-Brown Obsessive-Compulsive Scale and Anxiety Disorder Interview Schedule for DSM-IV Child Interview Schedule-Parent version, decreased significantly following intervention, with effect sizes of 3.38 and 2.29, respectively. Self-reported general anxiety and depression symptoms were not significantly reduced. CONCLUSIONS: This study provides preliminary support for CBT in treating the PANDAS subtype of pediatric OCD. This approach is also considered a safe and minimally invasive treatment approach. 相似文献
58.
59.
Adkins JW Weathers FW McDevitt-Murphy M Daniels JB 《Journal of anxiety disorders》2008,22(8):1393-1402
In this study psychometric properties of seven self-report measures of posttraumatic stress disorder (PTSD) were compared. The seven scales evaluated were the Davidson Trauma Scale (DTS), the PTSD Checklist (PCL), the Posttraumatic Stress Diagnostic Scale (PDS), the Civilian Mississippi Scale (CMS), the Impact of Event Scale-Revised (IES-R), the Penn Inventory for Posttraumatic Stress Disorder (Penn), and the PK scale of the MMPI-2 (PK). Participants were 239 (79 male and 160 female) trauma-exposed undergraduates. All seven measures exhibited good test-retest reliability and internal consistency. The PDS, PCL and DTS demonstrated the best convergent validity; the IES-R, PDS, and PCL demonstrated the best discriminant validity; and the PDS, PCL, and IES-R demonstrated the best diagnostic utility. Overall, results most strongly support the use of the PDS and the PCL for the assessment of PTSD in this population. 相似文献
60.
Nonsurgical repositioning of central venous catheters 总被引:2,自引:0,他引:2
Long-term central venous catheters are placed for total parenteral nutrition and/or chemotherapy. These catheters are placed surgically and fixed to the subcutaneous tissues. Complications include infection, venous thrombosis, and mechanical problems. The authors developed a method to percutaneously reposition displaced central venous catheters. The procedure is performed with fluoroscopy and modified angiographic techniques. Fifteen patients underwent a total of 17 procedures. The initial success rate was 76%; the final success rate was 88%. Many central venous catheters can be salvaged with this low-morbidity procedure, which negates the need for surgical intervention. 相似文献