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91.
After successful percutaneous transluminal coronary angioplasty (PTCA), 25 (20%) of 128 patients had elevation of creatine kinase MB isoenzyme (CK-MB). The increase was mild (mean 9% MB with total creatine kinase of 179 U/L). Three variables were significantly related to the enzyme elevation: chest pain, small branch vessel occlusion, and recent myocardial infarction. Of the patients with CK-MB elevation, 60% experienced chest pain and 32% sustained a small branch vessel occlusion during PTCA, compared with 11% and 8%, respectively, of the 103 patients without enzyme elevation (p less than 0.001 and p less than 0.01). Of 16 patients with recent myocardial infarction, seven (44%) had release of CK-MB. Although mild enzyme elevation after successful PTCA is likely due to a small amount of myocardial necrosis, this phenomenon was not associated with increased cardiac morbidity or mortality. Therefore, release of CK-MB without other clinical evidence for myocardial infarction after successful PTCA does not in itself warrant longer hospitalization, and routine serial enzyme determinations are probably unnecessary. By reducing the number of laboratory tests and the duration of hospitalization, the cost effectiveness of PTCA may be increased.  相似文献   
92.
Cardiac arrhythmias in patients with surgical repair of Ebstein's anomaly   总被引:4,自引:0,他引:4  
Preoperative, perioperative and postoperative arrhythmias in 52 consecutive patients who underwent operation for Ebstein's anomaly were reviewed. There were 25 male and 27 female patients (mean age 18 years, range 11 months to 64 years). Thirty-four patients had one or more documented arrhythmias preoperatively (18 had paroxysmal supraventricular tachycardia, 10 had paroxysmal atrial fibrillation or flutter, 13 had ventricular arrhythmia and 3 had high grade atrioventricular block). Seven patients without documented arrhythmias had a history typical of tachyarrhythmias. During the perioperative and early postoperative periods, 14 patients had atrial tachyarrhythmias and 8 had ventricular tachycardia or ventricular fibrillation. There were seven deaths between day 1 and 27 months after operation. Five of these deaths were sudden (all in male patients, aged 12 to 34 years), and four of the patients had had perioperative ventricular tachycardia or ventricular fibrillation. One patient was taking one antiarrhythmic agent and another patient was taking two at the time of sudden death. Of the 18 patients with paroxysmal supraventricular tachycardia and 9 patients with paroxysmal atrial fibrillation or flutter preoperatively who were followed up for a mean of 40 and 36 months, respectively, 22 and 33% continued to have symptomatic tachycardia. Of the 11 patients (mean age 9 years) without preoperative documentation or symptoms of arrhythmia, follow-up data were obtained (range 1 to 144 months, mean 31) in 9 patients. None died suddenly or developed symptomatic arrhythmia.  相似文献   
93.
94.
锌酞菁脂质体光动力作用引起小鼠肿瘤的细胞程序性死亡   总被引:3,自引:1,他引:3  
电镜观察了锌酞菁脂质体光动力作用引起小鼠MS-2纤维肉瘤的形态学变化。发现其作用很强,并对肿瘤细胞有明显的直接影响。肿瘤细胞的结构表现出明显的程序性细胞死亡(apoptosis,programmedceldeath)的特点:胞核染色质凝聚边集、核固缩、核破裂、染色质凝块流失、胞质内吞噬现象、胞膜表面肿胀粗钝的胞突形成、细胞碎裂等。加深了对锌酞菁脂质体光敏作用机理的认识,但其详细的发生机制和调节途径有待阐明。  相似文献   
95.
OBJECTIVE: To assess the diagnostic efficiency of positron emission tomography with 18-fluorine fluorodeoxyglucose in detecting breast cancer in augmented breasts. DESIGN: Retrospective study. SETTING: University hospital, Korea. SUBJECT: 9 cases or 8 patients with breasts augmented with paraffin or silicone. INTERVENTION: FDG-PET, mammography, and ultrasonography RESULTS: The mammogram detected the breast cancer in only 1 of 3 patients, and ultrasonography gave a false positive result in 1 patient with an augmented breast. In contrast, PET predicted all the cancers and 5/6 benign lesions. 2/3 breast cancers had axillary FDG uptake interpreted as showing metastatic involvement, and in 1 case with cancer with no axillary lymph node involvement there was no FDG uptake in the axilla, which correlated with the pathological finding. CONCLUSIONS: Although the high cost of PET makes its use as a screening test for all patients with augmented breasts unrealistic, it would be the best diagnostic choice if other methods failed.  相似文献   
96.
97.
98.
Background: Life-threatening small bowel obstruction (SBO) after Roux-en-Y gastric bypass can present with surprisingly minimal laboratory and plain x-ray findings. Based on a 10-year (1994-2003) experience of 1,409 open distal gastric bypasses, we present clinical and radiological findings in 29 patients with unusual forms of bowel obstruction. Methods: A retrospective chart review was conducted. A radiologist experienced in reviewing these in gastric bypass patients reviewed all computed tomography (CT) scans. Results: CT findings: The normal appearance and 7 recurring patterns of small bowel obstruction were identified. These include: 1) intussusception, 2) internal hernia through Petersen's space, 3) through Petersen's space and the mesenteric defect at enteroenterostomy, 4) through the mesenteric defect from the entero-enterostomy, 5) isolated biliary limb obstruction, 6) segmental non-anastomotic ischemia, and 7) internal hernia through bands. Clinical findings: 1 had peritonitis, and 1 had free air on plain film. WBC count was normal in 20/27 patients (74%) including 5/6 (83%) with dead bowel. 9/14 patients (62%) had "non-specific" findings on x-rays. 7 of these had an internal hernia (2 with volvulus and 2 with dead bowel), 1 had biliopancreatic limb obstruction, and 1 had peritonitis. Conclusion: Patients with SBO after distal gastric bypass may present with vague complaints and confusing laboratory and non-specific findings on x-rays. Delayed diagnosis can have catastrophic consequences. CT imaging with oral and intravenous contrast can be life-saving, and should be obtained in all gastric bypass patients with abdominal pain, particularly when all other parameters seem "normal". Unexplained abdominal pain should prompt exploration.  相似文献   
99.

Objective

To evaluate the efficacy of newly designed covered and non-covered coated colorectal stents for colonic decompression.

Materials and Methods

Twenty-six patients, (15 palliative cases and 11 preoperative) underwent treatment for the relief of colorectal obstruction using metallic stents positioned under fluoroscopic guidance. In 24 of the 26, primary colorectal carcinoma was diagnosed, and in the remaining two, recurrent colorectal carcinoma. Twenty-one patients were randomly selected to receive either a type A or type B stent; for the remaining five, type C was used. Type A, an uncovered nitinol wire stent, was lightly coated to ensure structural integrity. Type B (flare type) and C (shoulder type) stents were polyurethane covered and their diameter was 24 and 26mm, respectively. The rates of technical success, clinical success, and complications were analyzed using the chi-square test, and to analyse the mean period of patency, the Kaplan-Meier method was used.

Results

Thirty of 31 attempted placements in 26 patients were successful, with a technical success rate of 96.8% (30/31) and a clinical success rate of 80.0% (24/30). After clinically successful stent placement, bowel decompression occurred within 1-4 (mean, 1.58 ± 0.9) days. Five of six clinical failures involved stent migration and one stent did not expand after successful placement. In the preoperative group, 11 stents, one of which migrated, were placed in ten patients, in all of whom bowel preparation was successful. In the palliative group, 19 stents were placed in 15 patients. The mean period of patency was 96.25 ± 105.12 days: 146.25 ± 112.93 for type-A, 78.82 ± 112.26 for type-B, and 94.25 ± 84.21 for type-C. Complications associated with this procedure were migration (n=6, 20%), pain (n=4, 13.3%), minor bleeding (n=5, 16.7%), incomplete expansion (n=1, 3.3%), and tumor ingrowth (n=1, 3.3%). The migration rate was significantly higher in the type-B group than in other groups (p=0.038).

Conclusion

Newly designed covered and non-covered metallic stents of a larger diameter are effective for the treatment of colorectal obstruction. The migration rate of covered stents with flaring is higher than that of other types. For evaluation of the ideal stent configuration for the relief of colorectal obstruction, a clinical study involving a larger patient group is warranted.  相似文献   
100.

Objective

To compare sonography and mammography in terms of their diagnostic value in breast cancer cases which initially presented as an axillary mass without a palpable mass or other clinical symptoms.

Materials and Methods

Seven patients with enlarged axillary lymph nodes who first presented with no evidence of palpable breast lesions and who underwent both mammography and sonography were enrolled in this study. In six of the seven, the presence of metastatic adenocarcinoma was confirmed preoperatively by axillary needle aspiration biopsy; in four, subsequent sonographically-guided breast core biopsy performed after careful examination of the primary site indicated that primary breast cancer was present. In each case, the radiologic findings were evaluated by both breast sonography and mammography.

Results

Breast lesions were detected mammographically in four of seven cases (57%); in three of the four, the lesion presented as a mass, and in one as microcalcification. In three of these four detected cases, fatty or scattered fibroglandular breast parenchyma was present; in one, the parenchyma was dense. In the three cases in which lesions were not detected, mammography revealed the presence of heterogeneously dense parenchyma. Breast sonography showed that lesions were present in six of seven cases (86%); in the remaining patient, malignant microcalcification was detected at mammography. Final pathologic examination indicated that all breast lesions except one, which was a ductal carcinoma in situ, with microinvasion, were infiltrating ductal carcinomas whose size ranged from microscopic to greater than 3 cm. At the time of this study, all seven patients were alive and well, having been disease free for up to 61 months after surgery.

Conclusion

In women with a palpable axillary mass confirmed as metastatic adenocarcinoma, breast sonography may be a valuable adjunct to mammography.  相似文献   
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