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981.
BACKGROUND: Nitrate therapy can induce ischemic preconditioning with a consequent increase in tolerance to ischemia. In the context of acute coronary syndromes (ACS), nitrates may result in a different presentation. with greater protection. OBJECTIVES: To investigate in a population of patients with ACS whether previous chronic use of nitrates results in a different presentation of ACS. METHODS: We studied 287 patients (65 +/- 13 years, 66% male) admitted to our department in the first six months of 2005 with ACS (with and without ST-segment elevation). Of these, 8% were under nitrate therapy at the time of admission. In this group, 27% presented ACS without ST-segment elevation, while in the group without nitrates this value was 58% (p = 0.005). By univariate analysis, the use of nitrates was a predictor of the preferential occurrence of non-ST-segment elevation ACS (OR 0.27, 95% CI 0.10-0.71). After correction for the potential influence of variables (age, gender, previous revascularization and smoking) by multivariate logistic regression, nitrate therapy remained a borderline predictor of clinical presentation as non-ST-segment elevation ACS (OR 0.37, 95% CI 0.13-1.04, p = 0.059). CONCLUSIONS: Previous use of nitrates was associated with a tendency to present as non-ST-segment elevation ACS. This finding may be explained by the hypothesis that nitrates induce pharmacological preconditioning, reducing the transmural extent of myocardial infarction.  相似文献   
982.
BACKGROUND: Although cyanoacrylate tissue adhesives are frequently used in the closure of cutaneous lacerations and excisions, only a few reports comment on their usefulness as a dressing over sutured wounds. A new formulation of octyl-2-cyanoacrylate (Liquid Bandage; BAND-AID, Johnson & Johnson) is used as an occlusive protective film over minor cuts and scrapes. OBJECTIVE: An uncontrolled pilot study to assess the safety, efficacy, and cost of Liquid Bandage as an occlusive dressing over sutured facial excisions. METHODS: Patients undergoing excision of facial neoplasms were recruited. After conventional layered repair, Liquid Bandage was applied. On suture removal, the wounds were photographed and evaluated by three dermatologists, who assigned an overall outcome rating. The average cost of Liquid Bandage and routine wound care materials was calculated based on prices from three different pharmacies. RESULTS: Of the 18 wounds available at follow-up, 17 were assigned an overall outcome rating of good or excellent by at least one of the evaluators. Eleven wounds received an excellent rating from at least two of the evaluators. One case of distal flap necrosis occurred. Liquid Bandage proved to be less expensive than routine postsurgical wound care materials. CONCLUSIONS: Liquid Bandage dressing is safe and effective over sutured facial excisions.  相似文献   
983.
The Model for End-Stage Liver Disease (MELD) is used to assign priority for liver transplantation candidates. The Organ Procurement and Transplantation Network (OPTN) approved recognized exceptional diagnoses (RED's) for which MELD fails to accurately measure priority. Centers can request increased MELD points in cases not recognized by this policy (non-RED's). Our aim was to compare regional practices to justify non-RED requests for MELD adjustments. The UNOS/OPTN database was queried to extract all adult cases for which a non-RED MELD adjustment was requested from 2/27/02 until 8/27/03. The data were stratified by region and justification. Data for 29,510 listings were available. 26,947 had complete diagnosis information. There were 827 non-RED requests of which 477 (57.7%) petitions were approved by the regional review boards (RRBs). The approval rate varied significantly among regions (range: 28-75%, p<0.0001). The most common non-RED's were complications of portal hypertension (48%). The percentage of patients listed with non-RED's varied significantly among regions (0.7-8.3 %, p<0.0001), as did the proportion of patients transplanted with non-RED's (2.1-31.9%, p<0.0001). Demographics did not differ among regions requesting non-REDs.Widespread regional variations exist in the handling of requests for non-REDs. These variations point to the need for reform to standard exception criteria.  相似文献   
984.
Two embryonal CNS tumors, atypical teratoid/rabdoid tumor (AT/RT) and primitive neuroectodermal tumor (PNET), may be confused with each other and misdiagnosed. Here we report an infant with a congenital supratentorial tumor, which was detected by fetal MRI at 37 weeks gestation. On routine histological examination, the tumor was composed mainly of small undifferentiated cells, among which many rhabdoid cells and occasional sickle‐shaped embracing cells were observed. No mesenchymal or epithelial areas were evident. Our impression was that the tumor was an atypical example of AT/RT. Immunohistochemically, almost all the tumor cells were strongly positive for vimentin. However, epithelial membrane antigen was notably negative, and most of the tumor cell nuclei were clearly positive for INI1. In addition, many tumor cells were positive for neurofilament protein. There were also occasional small areas containing many tumor cells positive for glial fibrillary acidic protein. Finally, a diagnosis of PNET, with a rhabdoid phenotype and expression of neuronal and glial markers, was made. In the present case, application of INI1 immunostaining was very helpful for distinguishing PNET from AT/RT.  相似文献   
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986.
Cytokeratins (CKs) are expressed specifically in the cytoplasm of epithelial cells. We investigated the expression of CKs immunohistochemically in basal cell carcinomas (BCCs), epidermis overlying tumour, and skin tumor-associated amyloidosis (STA). Twenty cases of BCC, 11 of which had STA were included to the study. The primary antibodies of CK1-8 (AE3), CK10 (DEK-10), CK14 (LL002), CK17 (E3), CK18 (DC10), CK19 (KS19.1), CK 5/6/18 (LP34), CK8/18 (5D3) were applied to the section immunohistochemically. In BCCs without STA, CK1-8, CK14 and CK17 antibodies were expressed by tumour tissue in all biopsy specimens. In the BCCs with STA, tumour tissue was immunoreactive always with CK1-8 and CK17 antibodies, and commonly immunoreactive with anti-CK 14 antibody. In the epidermis overlying tumour tissue, there was positive immunoreactivity with anti-CK 1-8, CK 5/6/18, CK 10 and CK 14 antibodies in all biopsy specimens. Anti-CK 17 antibody was also positive in 17 biopsy specimens. STA is immunoreactive with anti-CK1-8 in all specimens. There was mild staining with anti-CK5/6/18 and with anti-CK19 whereas no immunoreactivity with anti-CK10 and CK18 antibodies was found. In conclusion, we could not find a significant CK expression difference between BCCs with and without STA. Weak positivity and a few number of CKs were shown in STA when compared with those of BCC and epidermis overlying tumour tissue expressing the more variable CKs. Interestingly, although CKs coexpressed in pairs consisting of one basic and one acidic CK, we detected predominantly basic CKs in STA.  相似文献   
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