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721.
OBJECTIVE: We present a new design for the radial forearm flap that includes a small monitor segment that is connected to the primary skin paddle by a fascial subcutaneous segment of tissue. This design modification permits buried flaps to be easily monitored and provides vascularized tissue coverage of the flap vessels as well as the great vessels in the neck. Immediate augmentation of the radical neck deformity can be achieved. SETTING: This study was conducted at a referral center. PATIENTS: Fifteen patients with squamous cell cancer of the pharynx and tongue base were included in this study. The defects in these patients were judged to be best reconstructed with a radial forearm free flap. RESULTS: All free flaps in this series survived. There was one case, described in detail, in which the fascial subcutaneous portion of the flap was exposed to salivary contamination. The flap vessels remained well protected and flap viability was unimpaired. 相似文献
722.
W. Prusseit B. Utz P. Berberich H. Kinder 《Journal of Superconductivity and Novel Magnetism》1994,7(1):231-233
Our technique of reactive thermal co-evaporation has been extended to fabricate large films (up to 4 in.) of YBa2Cu3O7 with high quality. A rotating substrate holder is used to separate the deposition and oxidation processes. This allows free access of the metal vapors. As large substrate wafers we use Al2O3, Si, and GaAs with buffer layers of CeO2, YSZ, and MgO, respectively. On all substrates, the uniformity of thickness and composition was better than 2%. Inductively measuredT c andj c (77 K) were 87.5±0.2 K and >1×106 A/cm2, respectively, across the full wafer area. This holds also for GaAs substrates due to a new procedure of capping by Si3N4. 相似文献
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OBJECTIVE: To evaluate endoscopic CO2 laser vaporization as a treatment of small glottic laryngeal carcinomas selected by means of video laryngo-stroboscopy. DESIGN: Prospective. SETTING: ENT department, University hospital, Free University Amsterdam. METHODS: Patients with a small glottic laryngeal carcinoma (stage Tis or T1a), were selected by means of video-laryngo-stroboscopy for a single stage endoscopic CO2 laser vaporization treatment as an alternative for radiotherapy. They were followed up for at least 24 months. RESULTS: Three of the 46 patients (6%) developed a local recurrence within 2 years; one of these could be treated once more with the CO2 laser, the other two were irradiated. None of these patients developed metastases in cervical lymph nodes or distant metastases. Most patients (41, 89%) assessed their voices after CO2 laser vaporization as normal or almost normal. Slight dysphonia was reported by five patients (11%). No serious dysphonia or aphonia occurred. CONCLUSION: Endoscopic CO2 laser vaporization, compared with radiotherapy or more extensive surgery, constitutes an adequate treatment for selected patients with small glottic laryngeal carcinomas. As a result of this treatment, it will be possible to preserve the larynx in more patients. 相似文献
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HF VanBrocklin KE Carlson JA Katzenellenbogen MJ Welch 《Canadian Metallurgical Quarterly》1993,36(11):1619-1629
In order to understand the structural features that might lead to an estrogen receptor (ER) based breast tumor imaging agent with improved uptake characteristics, we have synthesized several new analogs of 16 beta-fluoroestradiol (beta FES) and studied their tissue distribution in immature rats. The compounds we prepared were 11 beta-methoxy-beta FES (7a), 11 beta-ethyl-beta FES (7b), 17 alpha-ethynyl-beta FES (8c), 17 alpha-ethynyl-11 beta-methoxy-beta FES (8a), and 11 beta-ethyl-17 alpha-ethynyl-beta FES (8b). All of the analogs exhibit good affinity for ER, ranging at 25 degrees C from 10 to 460, with estradiol equal to 100. Measurement of their octanol/water partition coefficients by an HPLC method allowed us to estimate their level of nonspecific binding and thereby to predict their binding selectivity indices (BSI, i.e., the ratio of their ER-specific to nonspecific binding); the BSI values of three fluorine-substituted analogs exceed that of estradiol. These ligands have been labeled in the 16 beta position with fluorine-18 by the nucleophilic displacement of an alpha-disposed trifluoromethanesulfonate by [18F]fluoride ion. Reduction with lithium aluminum hydride produced the estradiol series ([18F]-7a-c), while treatment with lithium trimethylsilylacetylide afforded the ethynylated series ([18F]-8a-c). The synthesis time was 85 min for [18F]-7a-c and 120 min for [18F]-8a-c, with radiochemical yields ranging from 16 to 43%, and effective specific activities being 90-2900 Ci/mmol (3.3-107 TBq/mmol). In tissue distribution studies in immature female rats, all of the labeled analogs demonstrated ER-selective uptake in the principal target tissues, the uterus and the ovaries, and also in organs with lower titers of ER, the secondary target sites kidney, thymus, fat, and muscle. Although factors other than specific and nonspecific binding obviously affect the tissue distribution of these 16 beta-fluoroestrogens, we find that their ER-specific uptake by both the principal and the secondary target tissues correlates with their BSI values at a high level of statistical significance in most cases. The ethynylated-11 beta-methoxy analog [18F]-8a had high selectivity (uterus to blood ratio) after 3 h and exhibited the highest uterine uptake (percent injected dose/gram) of any fluorine-substituted estradiol ligand we have studied to date. This compound has been chosen for more detailed studies (to be described elsewhere), including clinical trials in human patients diagnosed with primary breast cancer. 相似文献
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