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81.
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The specific interactions of local anesthetic lidocaine hydrochloride with poly(acrylic acid) and poly(2-hydroxyethyl vinyl ether), as well as in a triple system composed of the drug and both polymers, have been studied in aqueous solutions by viscometric, turbidimetric, potentiometric, and FTIR spectroscopic methods. The mechanism of the drug binding to the polymers and the structures of the polycomplexes formed are clarified.  相似文献   
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Coronary Artery Disease (CAD) remains globally the leading cause of death and long-term morbidity. Among the many manifestations of CAD, acute coronary syndrome (ACS), ranging from unstable angina to acute myocardial infarction, is the most catastrophic event due to our inability to predict its occurrence. Despite improved treatments of CAD, ACS results in sudden death or permanent disability in a substantial percentage of patients. If we could predict the timing of ACS or better yet prevent its occurrence, we could alter the otherwise unfavorable course of CAD. Several studies have convincingly demonstrated that majority of all ACS develops from previously mild to moderate stenoses. Thus, based on these and autopsy studies, sudden disruption or rupture of the non-obstructive "vulnerable" atherosclerotic lesion is currently considered the cause of ACS. Recent clinical studies have substantiated earlier autopsy observations that plaque vulnerability is a systemic process, involving multiple locations concurrently. Although the exact inciting factors of the vulnerable plaque rupture are unknown, inflammation is accepted to be a pivotal event. The possibility of stabilizing the vulnerable plaques has strongly been supported by the lipid lowering trials, in which dramatic reduction of the acute coronary events was noted despite subtle improvements in luminal diameter. Furthermore, antiplatelet therapies have become an important preventative therapy due to the essential role of platelets in the aftermath of plaque rupture. Finally, various imaging modalities to diagnose the plaque vulnerability could help prevent the acute coronary events in the future.  相似文献   
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Mucosa-associated lymphoid tissue (MALT) lymphoma is a low-grade variant of B cell lymphoma that arises in extranodal tissue of the gastrointestinal tract, lung, salivary gland, thyroid, or other organ derived from the foregut. However, MALT lymphoma in the thymus is extremely rare. We report a case of thymic MALT lymphoma, extending to the neck, resected using combined thoracoscopic and transcervical approaches. To the best of our knowledge, thoracoscopic management of MALT lymphoma in the thymus has not previous been reported.  相似文献   
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We report intraoperative complications of thoracoscopic surgery for mediastinal tumors. Forty cases of mediastinal tumor were undergone thoracoscopic surgery at the hospital from 1999 to 2002. The patient's ages ranged from 18 to 74 years old with a mean of 47.7. Location of these tumors were anteriormediastinal in 20 cases, middlemediastinal in 6 cases, posteriormediastinal in 11 cases, and superiormediastinal in 3 cases. Intraoperative complications were rupture of the cyst in 9 cases, bleeding over 150 ml in 5 cases, injury of lung caused by adhesiolysis in 5 cases, and injury of nerve in 3 cases. The mean operation time was 103.8 minutes. Postoperative hospital stay ranged from 2 to 22 days with a mean of 5.9 days. All are alive with no recurrences or postoperative complications.  相似文献   
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The bcl-2 homologue antagonist/killer (BAK) is a potently apoptosis-inducing gene and plays an important role in modulating apoptosis in epithelial cells. We have analyzed the mutation of the entire coding region of BAK gene in 107 Korean advanced gastric adenocarcinomas by polymerase chain reaction-single strand conformation polymorphism and sequencing. Homozygous deletions were not found in these samples. Only three cases of 107 gastric adenocarcinomas (2.8%) exhibited the BAK mutations. Two of them exhibited missense mutations and the remaining one had a silent mutation. All of these mutations were exclusively detected in exon 2. Mutations in the BAK gene were observed only in advanced gastric adenocarcinomas with extensive metastases of regional lymph nodes. The data presented here suggest that the mutations of BAK gene rarely occurred in advanced gastric adenocarcinomas.  相似文献   
89.
Nam JH  Mun JI  Kim SI  Kang SW  Choi KH  Park K  Ahn CW  Cha BS  Song YD  Lim SK  Kim KR  Lee HC  Huh KB 《Transplantation》2001,71(10):1417-1423
BACKGROUND: Our study was undertaken to investigate the pathogenesis and possible risk factors for postrenal transplantation diabetes mellitus (PTDM). METHODS: We recruited 114 patients with normal glucose tolerance (NGT) and performed both 75-g oral glucose tolerance tests (OGTT) and short insulin tolerance tests 1 week before and 9-12 months after transplantation. RESULTS: The subjects were classified into three groups by World Health Organization criteria on the basis of OGTT after transplantation: (a) 36 (31.6%) subjects with normal glucose tolerance; (b) 51 (45.7%) subjects with impaired glucose tolerance (IGT); and (c) 27 (23.7%) subjects with postrenal transplantation diabetes mellitus. Dosages of steroid and cyclosporine were equivalent among the three groups. Before transplantation, the fasting and 2-hr plasma glucose and proinsulin/insulin (PI/I) ratios were significantly higher in the IGT and PTDM groups than in the NGT group, but the insulin sensitivity index (ISI) was not significantly different among the three groups. In addition, the area under the curve-insulin on OGTT was significantly lower in the PTDM group than in the NGT group. After transplantation, however, the ISI was increased in all groups. Furthermore, the ISI and PI/I ratios revealed significantly higher values in the PTDM group than in the NGT group after transplantation. CONCLUSIONS: These results revealed that fasting and 2-hr plasma glucose levels, as well as the proinsulin/insulin ratio before transplantation, are both possible indicators of beta-cell dysfunction and may be predictors for the development of PTDM. Furthermore, beta-cell dysfunction, rather than insulin resistance, was proven to be the main factor for the pathogenesis of PTDM.  相似文献   
90.
Dysgerminoma of the ovary with precocious puberty: a case report.   总被引:1,自引:0,他引:1  
Ovarian dysgerminoma is usually hormonally inert, but when it contains syncytiotrophoblastic giant cells or undergoes malignant transformation, the level of estradiol might be elevated. A 6-year-old girl contracted ovarian dysgerminoma with precocious puberty, and her levels of beta-human chorionic gondaotropin, alpha-fetoprotein and estradiol were high. After resection of the tumor, levels of tumor markers became normal and precocious puberty disappeared. We report this unusual type of dysgerminoma with a brief review of the literature.  相似文献   
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