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981.
Funari SL 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》2003,19(6):1841-1844
Sexual transmission of the human immunodeficiency virus (HIV) continues to pose a public health problem worldwide. Men who have sex with men are still at differential risk of infection. Although there is evidence to claim that HIV can be transmitted by oral sex, the perception of this risk is ambiguous and relates paradoxically to behavior change. New models of risk perception must be developed in various areas of knowledge to obtain a fuller understanding of this phenomenon. 相似文献
982.
Glantz L Ezri T Cohen Y Konichezky S Caspi A Geva D Leviav A 《Anesthesia and analgesia》2003,96(6):1566-71, table of contents
Coronary revascularization reduces cardiac complications associated with noncardiac surgery in patients with severe coronary disease. However, patients undergoing emergency noncardiac surgery soon after coronary bypass operations may still be vulnerable to ischemic myocardial events. We prospectively evaluated the incidence of myocardial ischemia in 82 consecutive patents scheduled for sternectomy in the first (Group 1; 35 patients) or second (Group 2; 47 patients) week after coronary artery bypass graft (CABG) surgery. The interval between CABG surgery and sternectomy in Groups 1 and 2 was 6 days (range, 4-7 days) and 11 days (range, 8-14 days), respectively. Electrocardiographic (ECG) changes consistent with myocardial ischemia were assessed with a two-channel Holter system for 48 h. There were no between-group differences in updated Acute Physiology and Chronic Health Evaluation score, use of beta-blockers, or perioperative hemodynamic changes. The incidence of ECG changes consistent with myocardial ischemia was fivefold more frequent in Group 1 (22.85% versus 4.25%; P < 0.05). Of the ischemic patients in Group 1, 25% experienced a perioperative acute myocardial infarction (one was fatal). There were no infarcts in Group 2. Thus, patients appear to be prone to coronary events during sternectomy performed early after CABG surgery. Although the incidence of ischemia did not differ from that previously reported after CABG surgery alone, further investigation is required to determine whether the findings obtained in this high-risk population are generalizable to patients undergoing noncardiac surgery soon after uneventful CABG surgery. IMPLICATIONS: This study demonstrates an increased incidence of myocardial ischemia when sternectomy for mediastinitis is performed within one week of coronary artery bypass graft surgery, and this ischemia is associated with a 25% incidence of myocardial infarction. 相似文献
983.
Benign multicystic mesothelioma is a rare disease with a high tendency to local recurrence, but with no tendency to malignancy. The correct diagnosis can be made by histopathological examination in conjunction with immunohistochemical and ultrastructural evaluations. A case of benign cystic mesothelioma recurring three times in a 48-year-old woman is reported, and the management of this disease and the importance of radical surgery are discussed. 相似文献
984.
Extracapsular parathyroid haemorrhage is a rare but ominous occurrence, which may cause cervico-mediastinal haematoma and a severe calcaemia imbalance. We identified only 23 cases reported in the literature and these were always secondary to adenoma, hyperplasia or cysts, and never to carcinoma. We describe a case of a 56-year-old man who was admitted to our Institute because of the sudden development of an anterior neck swelling, together with dysphagia, dyspnoea and hoarseness. Physical examination revealed a large ecchymosis extending from the anterior neck to the upper chest, while the early symptoms had disappeared. Laboratory studies, ultrasonography and 99mtTC-Sestamibi scintiscan demonstrated the presence of primary parathyroidism due to a right inferior parathyroid neoplasm. At operation, the parathyroid was excised en bloc with the right thyroid lobe because they were joined together by an extensive fibrous reaction. Histological examination showed a well-differentiated parathyroid carcinoma with evidence of recent haemorrhage. To the best of our knowledge this is the first case of extracapsular haemorrhage due to a parathyroid carcinoma. In summary, although parathyroid haemorrhage is a rare condition, it should always be suspected when a painful mass or diffuse swelling suddenly occurs in the anterior neck, with or without ecchymosis, especially when serum calcium and phosphorus are abnormal. 相似文献
985.
The authors assess the incidence of locoregional chronic pain after inguinal hernia repair. One hundred consecutive patients, with a mean age of 65.4 years, suffering from primary monolateral inguinal hernia, underwent suture-less mesh-plug hernioplasty. In all cases the inguinal nerves were identified. In the early postoperative period, a questionnaire was given to all patients in order to assess the frequency, type and intensity of postoperative locoregional pain and the impact of the pain on their quality of life. Sixty patients were available for follow-up with clinical examination and these were given the same questionnaire 2-4 years after hernioplasty. Pain intensity was scored by means of a visual-analogue scale (from 0 to 10). The incidence of locoregional pain after hernioplasty was 13.0% in the early postoperative period and 25.0% after a longer period of follow-up. None of the patients presented recurrent hernia. The symptomatic patients reported mild or moderate neurogenic pain. Severe pain was not reported. On the whole, the presence of mild-to-moderate chronic pain had no impact on the patients' quality of life. Our study confirms the high incidence of locoregional chronic pain even after sutureless mesh-plug hernioplasty, but that this has no serious effects on the patients' quality of life. 相似文献
986.
987.
988.
Morabito A Filippelli G Palmeri S Cascinu S Ferraù F Zagonel V Gattuso D Catalano V Capaccetti B Franciosi V Accurso V Scinto F Gasparini G 《Breast cancer research and treatment》2003,78(1):29-36
Purpose. To evaluate the activity and toxicity of gemcitabine and vinorelbine (GemVin), in patients with advanced breast cancer, previously treated with anthracyclines alone or with taxanes.
Patients and methods. Nine patients were entered into the phase I and 50 patients were entered into the phase II study. Gemcitabine was administered beginning with the dose of 800 mg/m2 and vinorelbine was given at the fixed dose of 25 mg/m2, both on days 1 and 8, every 21 days. Escalated dose levels of gemcitabine were planned by increments of 200 mg/m2 per level. The median age of the 50 assessable patients for the phase II study was 56.5 years (range 30–70) and median performance status (PS, ECOG score), 1 (range 0–2). The dominant sites of metastases were viscera in 40, bone in five and soft tissue in five patients. First-line chemotherapy for metastatic disease with taxanes and anthracyclines or with anthracyclines alone was administered in 36 and 14 patients, respectively.
Results. The optimal schedule for the combination was gemcitabine 800 mg/m2 and vinorelbine 25 mg/m2. The maximum tolerated dose of gemcitabine was 1000 mg/m2, with grade 4 neutropenia occurring in two cases at this dose level. Overall, 267 cycles were given to the 50 patients enrolled into the phase II (mean 5.3; range 3–9). The schedule was well tolerated: three patients experienced grade 4 neutropenia and another four patients experienced grade 3 anemia. Non-hematological toxicities were moderate. A major objective response was observed in 42% of patients (95% confidence interval (CI), 28–57%), with complete remission in four (8%) and partial response in 17 (34%) patients. The median time to progression was 6 months. Activity as well as toxicity were similar in the subgroups of the patients pretreated either with combinations of taxanes and anthracyclines or anthracyclines alone.
Conclusions. The optimal GemVin schedule is an effective and well tolerated second-line therapy in patients with metastatic breast cancer pre-treated with anthracycline – based schedules or with combinations of anthracyclines and taxanes. 相似文献
989.
Stable expression of antisense urokinase mRNA inhibits the proliferation and invasion of human hepatocellular carcinoma cells 总被引:2,自引:0,他引:2
Urokinase-type plasminogen activator (u-PA) plays a key role in malignant tumor behavior. We have previously shown that the expression of high levels of u-PA mRNA in human hepatocellular carcinoma (HCC) biopsies was inversely correlated with the survival of the patients. In order to evaluate the involvement of u-PA in the invasive and infiltrating properties of HCC cells, the SKHep1C3 cell line was stably transfected with an expression vector containing the 5' portion (257 bp) of u-PA cDNA in the antisense orientation. u-PA mRNA expression and its protein level and enzymatic activity were specifically inhibited in the antisense transfectants. A comparable inhibition of the u-PA receptor (u-PAR) mRNA and protein was also evidenced in the antisense transfected cells compared with the control ones. At the functional level, the SKHep1C3-AS cells showed a significant reduction in proliferation, Matrigel invasion, and motility assays compared to parental and vector-alone cells. These results indicate that u-PA is an essential factor in the growth and invasiveness of human hepatocarcinoma cells. Antisense u-PA strategy might be a potential approach to reduce tumor growth as well as the invasive capacity of the malignant cells in HCC. 相似文献
990.
Downregulation of bcl-2 expression in lymphoma cells by bcl-2 ARE-targeted modified,synthetic ribozyme 总被引:2,自引:0,他引:2
Luzi E Papucci L Schiavone N Donnini M Lapucci A Tempestini A Witort E Nicolin A Capaccioli S 《Cancer gene therapy》2003,10(3):201-208
Synthetic ribozymes are catalytic RNA molecules designed to inhibit gene expression by cleaving specific mRNA sequences. We investigated the potential of synthetic ribozymes to inhibit bcl-2 expression in apoptosis defective bcl-2 overexpressing tumors. A chemically stabilized hammerhead ribozyme has been targeted to the A+U-rich regulative element of bcl-2 mRNA that is involved in bcl-2 gene switch-off during apoptosis. The design of the ribozyme was based on the results of probing accessibility of the RNA target in cellular extracts with antisense DNA. The ribozyme was lipotransfected to a bcl-2 overexpressing human lymphoma cell line (Raji). The cellular uptake of this ribozyme resulted in a marked reduction of both bcl-2 mRNA and BCL-2 protein levels and dramatically increased cellular death by apoptosis. Our results suggest a potential therapeutic application of such ribozyme for the treatment of bcl-2 overexpressing tumors. 相似文献