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991.
992.
9-Benzyl-3-methylene-1,5-di-p-toluenesulfonyl-1,5,9-triazacyclododecane (CADA) has been identified as a novel antiviral lead compound with significant anti-human immunodeficiency virus and anti-human herpesvirus 7 activity. Surprisingly, this compound selectively decreased the expression of the CD4 glycoprotein, the primary receptor needed for the entry of both viruses. Herein, we describe the CD4 down-modulating and antiviral potencies of more than 25 CADA derivatives. Flow cytometric evaluation of cellular CD4 receptor expression in T cells demonstrated the specific CD4 down-modulating capacity of the CADA derivatives, with IC(50) values similar to those obtained in the antiviral assays. The close correlation observed between the CD4 down-regulating and anti-HIV potencies of the CADA derivatives further points to CD4 receptor down-modulation as the primary mode of antiviral action for this group of compounds.  相似文献   
993.
PURPOSE: High prevalence of squamous cervical intraepithelial neoplasia (CIN) linked to oncogenic human papillomavirus (HPV) exits in HIV-infected women. Hepatocyte growth factor (HGF) and its receptor, c-Met, promote cell proliferation and are involved in tumor progression. Nothing is yet known about their expression in low- and high-grade CIN. Therefore, the expression, localization, and behavior of HGF and c-Met in normal and dysplastic cervical epithelium were investigated. EXPERIMENTAL DESIGN: We studied normal cervical mucosa from 10 healthy women, and low- and high-grade cervical lesions, uninfected (condyloma acuminata) or infected with oncogenic HPVs, from 40 HIV-negative and 48 HIV-positive women, using in situ molecular techniques, immunocytochemistry and morphoquantitative methods. RESULTS: In 154 oncogenic HPV-infected CIN encountered in biopsy samples, the total number of epithelial cell layers increased significantly during lesion progression. This number was significantly higher in HIV-positive than in HIV-negative women for CIN1 and CIN2 (P < 0.025 to P < 0.01). In HIV-negative women, the number and percentage of HGF and c-Met immunostained cell layers, and the intensity of immunostaining were enhanced in oncogenic HPV-infected lesions as compared with normal mucosa and condyloma acuminata. The latter parameters were significantly higher in tissues of HIV-positive women (oncogenic HPV-infected CIN1 and CIN2, normal-appearing mucosa contiguous to CIN, condyloma acuminata) than in the corresponding tissues of HIV-negative women (P < 0.025 to P < 0.0001). CONCLUSIONS: Overexpression of HGF/c-Met complex strongly correlates with oncogenic HPV and HIV infection. This overexpressed complex may stimulate cell proliferation in condyloma acuminata and participate in tumor progression in oncogenic HPV-infected lesions.  相似文献   
994.
PURPOSE: To analyse predictive factors of acute urinary morbidity after transperineal permanent prostate brachytherapy. METHODS AND MATERIALS: Sixty patients treated in a phase 2 study with iodine-125 brachytherapy (9/1998 to 2/2000) for localised prostate adenocarcinoma were analysed after at least 1-year follow-up. Prescribed dose was 144 Gy and all patients had a pre-planning and a post-implant dosimetry. Urinary morbidity was evaluated prospectively using the Radiation Therapy Oncology Group (RTOG) scale. We examined the relationship between pre-implant ultrasound prostate volume, post-implant CT-scan prostate volume, neoadjuvant hormonotherapy, total number of needles and seeds, post-implant dosimetry variables, first 30 vs. last 30 treated patients and post-implant urinary morbidity. RESULTS: All patients experienced some degree of urinary distress symptoms after treatment. Symptoms were generally mild grade 1 in 56% and grade 2 in 10% lasting less than 6 months. Eight patients (13%) required bladder catheter for acute urinary obstruction. At 1-year follow-up, nine patients (15%) complained from persistent dysuria requiring in three cases endoscopic prostate resection. The percentage of urethra volume receiving 216 Gy (cut-off 40%) and the pre-implant prostate volume (cut-off 31 ml) were the only statistically significant predictor of grade 2-3 or persistent urinary morbidity on multivariate analysis. CONCLUSION: Our short-term data suggest that both pre-implant prostate volume value and post-implant V.U. 150 value might be predictors for urinary morbidity after prostate brachytherapy.  相似文献   
995.
996.
Hyperthermia therapy (HT) is the exposure of a region of the body to elevated temperatures to achieve a therapeutic effect. HT anticancer properties and its potential as a cancer treatment have been studied for decades. Techniques used to achieve a localised hyperthermic effect include radiofrequency, ultrasound, microwave, laser and magnetic nanoparticles (MNPs). The use of MNPs for therapeutic hyperthermia generation is known as magnetic hyperthermia therapy (MHT) and was first attempted as a cancer therapy in 1957. However, despite more recent advancements, MHT has still not become part of the standard of care for cancer treatment. Certain challenges, such as accurate thermometry within the tumour mass and precise tumour heating, preclude its widespread application as a treatment modality for cancer. MHT is especially attractive for the treatment of glioblastoma (GBM), the most common and aggressive primary brain cancer in adults, which has no cure. In this review, the application of MHT as a therapeutic modality for GBM will be discussed. Its therapeutic efficacy, technical details, and major experimental and clinical findings will be reviewed and analysed. Finally, current limitations, areas of improvement, and future directions will be discussed in depth.  相似文献   
997.
998.
The imaging of regional cerebral blood flow (rCBF) by 99mTc-d, 1 HM-PAO and SPECT is described. Its relevance to clinical syndromes, such as stroke, transient ischemic attacks, various forms of dementia, epilepsy, and subarachnoid hemorrhage, is reported.  相似文献   
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