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PURPOSE: To evaluate the effect of immediate androgen suppression in conjunction with standard external beam irradiation vs. radiation alone on a group of pathologically staged lymph node-positive patients with adenocarcinoma of the prostate. METHODS AND MATERIALS: A national prospective randomized trial (RTOG 85-31) of standard external beam irradiation plus immediate androgen suppression vs. external beam irradiation alone was initiated in 1985 for patients with locally advanced adenocarcinoma of the prostate. One hundred seventy-three of the patients in this trial had biopsy-proven pathologically involved lymph nodes. Ninety-eight of these patients received radiation plus the immediate androgen suppression (LHRH agonist), while 75 received radiation alone with hormonal manipulation instituted at the time of relapse. RESULTS: With a median followup of 4.9 years, estimated progression-free survival with PSA < 1.5 ng/ml at 5 years was 55% for the patients who received radiation plus immediate LHRH agonist vs. 11% of the patients who received radiation alone with hormonal manipulation at relapse (p = 0.0001). Because all of these patients had locally advanced disease (i.e., pathologically positive lymph nodes), stage does not explain this difference in outcome, and Gleason grade was not statistically different between the two groups. Estimated absolute survival at 5 years for the radiation and LHRH group was 73 vs. 65% for the radiation alone group who received androgen suppression at relapse. Estimated disease-specific survival at 5 years was 82% for the radiation and immediate LHRH agonist group and 77% for the radiation-alone group. CONCLUSION: Patients with adenocarcinoma of the prostate and pathologically involved pelvic lymph nodes (pN+ or clinical stage D1) should be seriously considered for external beam irradiation plus immediate hormonal manipulation over radiation alone with hormonal manipulation at the time of relapse.  相似文献   
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Jirds support the entire life-cycle of Strongyloides stercoralis. We therefore used this host as a model to define the mechanism of the immune response to a challenge infection, as well as the parasite stage effected by the response. Jirds given a primary infection of S. stercoralis are resistant to re-infection. The use of implanted diffusion chambers containing larvae showed that the immune response killed the third-stage larvae, and this was confirmed by subcutaneous infections. The larvae of a challenge infection are killed within 48 h, a time period too short to allow for the development of L4 and adult worms. The immune response is dependent on both a serum factor and cells, suggestive of an ADCC type response.  相似文献   
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The principal (alpha 1) subunit of purified skeletal muscle dihydropyridine-sensitive (L-type) calcium channels is present in full-length (212 kDa) and COOH-terminal truncated (190 kDa) forms, which are both phosphorylated by cAMP-dependent protein kinase (cA-PK) in vitro. Immunoprecipitation of the calcium channel from rabbit muscle myotubes in primary cell culture followed by phosphorylation with cA-PK, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and two-dimensional phosphopeptide mapping revealed comparable phosphorylation of three COOH-terminal phosphopeptides found in the purified full-length alpha 1 subunit. Stimulation of muscle myotubes with a permeant cAMP analogue, 8-(4-chlorophenylthio) adenosine 3',5'-cyclic monophosphate, prior to immunoprecipitation of alpha 1 results in a 60-80% reduction of cA-PK catalyzed "back" phosphorylation of each of these sites in vitro in calcium channels purified from the cells, indicating that these sites are phosphorylated in vivo in response to increased intracellular cAMP. Serine 687, the most rapidly phosphorylated site in the truncated 190-kDa alpha 1 subunit, was observed as a minor phosphopeptide whose level of phosphorylation was not significantly affected by stimulation of endogenous cA-PK in the myotubes. The COOH-terminal sites, designated tryptic phosphopeptides 4, 5, and 6, were identified as serine 1757 (phosphopeptides 4 and 6) and 1854 (phosphopeptide 5) by a combination of protease cleavage, phosphorylation of synthetic peptides and fusion proteins, specific immunoprecipitation, and phosphopeptide mapping. Phosphorylation of serines 1757 and 1854 in the COOH-terminal region of the 212-kDa alpha 1 subunit in intact skeletal muscle cells may play a pivotal role in the regulation of calcium channel function by cA-PK.  相似文献   
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Sound-processing strategies that use the highly non-random structure of natural sounds may confer evolutionary advantage to many species. Auditory processing of natural sounds has been studied almost exclusively in the context of species-specific vocalizations, although these form only a small part of the acoustic biotope. To study the relationships between properties of natural soundscapes and neuronal processing mechanisms in the auditory system, we analysed sound from a range of different environments. Here we show that for many non-animal sounds and background mixtures of animal sounds, energy in different frequency bands is coherently modulated. Co-modulation of different frequency bands in background noise facilitates the detection of tones in noise by humans, a phenomenon known as co-modulation masking release (CMR). We show that co-modulation also improves the ability of auditory-cortex neurons to detect tones in noise, and we propose that this property of auditory neurons may underlie behavioural CMR. This correspondence may represent an adaptation of the auditory system for the use of an attribute of natural sounds to facilitate real-world processing tasks.  相似文献   
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An unsupervised anomaly detection algorithm for synthetic aperture radar (SAR) images, making use of polarized data, is developed. The processing contains several stages, including calibration of the images, extraction of information parameters and speckle filtering, detection of candidate pixels and application of a constant false alarm rate (CFAR) morphology operator. The developed algorithm is independent of the anomaly's radar cross section (RCS); it depends only on the physical structure of the observed objects. The proposed processing is non-iterative, adaptive and semi-automatic. Performance evaluation shows improved performance of the algorithm over the common alternatives.  相似文献   
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在今年3月举行的iPad2发布会上,乔布斯将iPhone、iPod和iPad称为是后PC设备,并表示它们比传统台式机或笔记本电脑更直观、更易用。那么,4个月后,我们发现后PC时代确实已经到来。计算设备及用户与之  相似文献   
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