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31.
Lymphoscintigraphy associated with radioguided biopsy of the sentinel node (SN) is well established in clinical practice for melanoma. In breast cancer, the SN concept is similarly valid, and lymphoscintigraphy is a useful method for localizing the axillary SN. The aim of this study was to optimize the lymphoscintigraphy technique in association with a gamma ray detecting probe (GDP) for identifying and removing the SN in breast cancer patients. METHODS: Two-hundred fifty patients with operable breast tumor underwent lymphoscintigraphy before surgery. Three different size ranges of 99mTc-labeled colloid particles (<50, <80 and 200-1000 nm) were used, with either subdermal (above tumor) or peritumoral injection. Early and late scintigraphic images were obtained in anterior and oblique projections, and the skin projection of the detected SN was marked. Sentinel nodes were identified and removed with the aid of the GDP during breast surgery; they were tagged separately. Complete axillary dissection followed. In 40 patients, a blue dye was also administered in addition to subdermal radiolabeled colloid to compare blue dye mapping with lymphoscintigraphy localization. RESULTS: Lymphoscintigraphy successfully revealed lymphatic drainage in 245 of 250 patients (98%). The axillary SN was identified in 240 patients (96%). SN biopsy correctly predicted axillary node status in 234 of 240 patients (97.5%). Lymphoscintigraphy and GDP detected the SN most easily and consistently when 200-1000 nm colloid was administered subdermally in an injection volume of 0.4 ml. Blue dye mapping was successful in 30 of 40 patients (75%). In 26 of these patients, the dye and lymphoscintigraphy identified the same node; in 4 cases different nodes were identified. None of these four patients had axillary disease. CONCLUSION: Lymphoscintigraphy is a simple procedure that is well tolerated by patients. Sentinel node identification is more reliable when large-size radiolabeled colloids are injected in a relatively small injection volume (0.4 ml). Use of a GDP greatly facilitates precise pinpointing and rapid removal of the SN.  相似文献   
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V. Veronesi 《Wear》1979,55(2):265-276
Striking elements (printing wires and type slugs) and inked ribbons used in impact printers were investigated. Wires used in the printhead of a card printer did not show any appreciable damage. The wire sides of the inked ribbons were unmarked but the outer nylon fibres of the woof in the card sides were damaged and eventually broken by the running cardstock. The characters mounted in a high speed printer deteriorate with use. The 0 characters are severely worn (dimensional loss of 0.25 mm) whereas no measurable abrasion occurred in two typographic symbols having a shorter striking history. Worn faces are scratched by fine furrows parallel to the motion of the type slugs; in the most severely worn 0 characters the hardened case was completely removed. Wear occurs by an abrasive mechanism. When struck the characters slide against the inked ribbon and the small solid particles dispersed in the ink or adhering to the yarn act as a fine abrasive. The fabric of the inked ribbons employed in another card printer had suffered severe deterioration by the end of a suitable life test. The degradation was due to the mechanical effects on the ribbons being struck by the impacting characters.  相似文献   
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Editor's NoteNigel Helyer, sculptor and sound artist; Francesca Veronesi, architect; and Daniel Woo, interaction designer; discuss several of their AudioNomad projects, exploring mobile surround sound and interactivity. Cofounded five years ago by Helyer (creative director) and Woo (scientific director), AudioNomad is an art and science research program—a location-aware virtual and augmented audio-reality system. Its software allows a mobile user or vehicle to perform a soundscape. This article discusses some of the challenges in the development of three works: location-aware, surround-sound installations mounted on ships; mobile handheld devices for individual pedestrian use; and interactive surround-sound installations for static museum exhibition.—Norie Neumark  相似文献   
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In this paper we show how a simple methodology for the set-point following performance assessment and automatic tuning of a PI controller can be employed effectively in a real industrial application. In particular, a flow control loop in a pharmaceutical plant is considered. Practical issues related to the implementation in a Distributed Control System are discussed. Results show that the technique is capable of significantly improving the performance of the controller.  相似文献   
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Decabromodiphenyl ether (BDE-209), the primary constituent of a widely used flame retardant formulation, is present at relatively high levels in sediments and macroinvertebrates of the River Po. Since it was demonstrated that BDE-209 can be biotransformed to smaller and more toxic polybrominated dipheyl ethers (PBDEs), the main objective of this study was to assess whether the large quantities of BDE-209 present in the River Po are bioavailable to the higher levels of the food web and are biotransformed in feral fishes. To this aim, 23 cyprinids, mainly common carp, were analysed for the hepatic contents of PBDEs. Contrary to sediments and invertebrates of the same area, no fish sample contained detectable levels of BDE-209. All fishes contained typical PBDE representatives, e.g. BDE-47, BDE-99, BDE-100, BDE-153 and BDE-154, but more importantly they contained three congeners, i.e. BDE-179, BDE-188 and BDE-202, which are not present in any technical formulations and are known products of BDE-209 debromination in fish. The age of carps had no effects on the bioaccumulation of PBDEs. Conversely, the contents of PCBs, which also were determined in the same fish samples, showed a positive correlation with age. Both groups of chemicals displayed a tendency to a higher contamination in male fish. This study shows that BDE-209 enters the food web of the River Po contributing to the load of lower brominated PBDEs and thus to the load of chemical stressors threatening the aquatic life of the major Italian watercourse.  相似文献   
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Salmonella is one of the most common pathogens in the European Union which can spread in the domestic environment due to incorrect food handling practices. This study has investigated the efficacy of the Theory of Planned Behavior (TPB) to uncover the processes that lead to the formation of the intentions and thus to a specific behavior, i.e. consuming meat and fresh sausages only if well cooked. Two parallel longitudinal studies comprising Italian young adults and adults were carried out. In a two week period, participants were administered two questionnaires measuring behavioral intentions and their antecedents in the first wave, and self-reported behavior toward the target behavior in the second one.Results showed the superior predictive power of the TPB plus past behavior. From a cognitive perspective, the samples differed: the actual behavior of young adults derives from intentions and perceived control, whereas the behavior of adults depends only on past behavior. Findings suggest that food risk-communication should consider the differences in behavior models.  相似文献   
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PURPOSE: Monitoring of fenretinide (4HPR) levels, kinetics, and effects on retinal was performed in patients who participated in a phase I trial and who continued to be treated for 5 years as phase III trial patients. Accumulation of 4HPR in the breast was also assessed. PATIENTS AND METHODS: Plasma concentrations of 4HPR, of its main metabolite N-(4-methoxyphenyl)retinamide (4MPR), and of retinol were assayed by high-performance liquid chromatography (HPLC) in breast cancer patients treated orally with 4HPR 200 mg/d for 5 years with a 3-day drug interruption at the end of each month. RESULTS: 4HPR, at 200 mg/d, resulted in average 4HPR plasma levels of approximately 1 mumol/L, which remained steady and caused steady retinol level reduction; 4MPR levels, similar to those of 4HPR, slightly but significantly increased during the first 35 months, but at 5 years they were similar to those at 5 months. During daily treatment, baseline retinol concentrations were reduced by 71%; after a 3-day drug interruption, all patients recovered and the mean reduction was 38%. After discontinuation of 5-year treatment, 4HPR and 4MPR half-lives (t1/2 beta) were 27 and 54 hours, respectively, similar to those reported after 28 daily treatments. After 6 and 12 months, the concentrations of 4HPR were at the limit of detectability (0.01 mumol/L), whereas those of 4MPR were five times higher. Baseline retinol concentrations were already recovered after 1 month. Accumulation of this retinoid in the breast was evidenced by concentrations of 4HPR and 4MPR in nipple discharge and in breast biopsies that were 10 and 20 times higher, respectively, than those found in plasma. CONCLUSION: 4HPR, at 200 mg/d for 5 years, resulted in constant drug plasma levels and constant retinol level reduction. After treatment interruption, 4HPR plasma concentrations decreased at the limit of detectability at 6 months and baseline retinol plasma concentrations were recovered after 1 month.  相似文献   
40.
BACKGROUND: Axillary lymph-node dissection is an important staging procedure in the surgical treatment of breast cancer. However, early diagnosis has led to increasing numbers of dissections in which axillary nodes are free of disease. This raises questions about the need for the procedure. We carried out a study to assess, first, whether a single axillary lymph node (sentinel node) initially receives malignant cells from a breast carcinoma and, second, whether a clear sentinel node reliably forecasts a disease-free axilla. METHODS: In a consecutive series of 163 women with operable breast carcinoma, we injected microcolloidal particles of human serum albumin labelled with technetium-99m. This tracer was injected subdermally, close to the tumour site, on the day before surgery, and scintigraphic images of the axilla and breast were taken 10 min, 30 min, and 3 h later. A mark was placed on the skin over the site of the radioactive node (sentinel node). During breast surgery, a hand-held gamma-ray detector probe was used to locate the sentinel node, and make possible its separate removal via a small axillary incision. Complete axillary lymphadenectomy was then done. The sentinel node was tagged separately from other nodes. Permanent sections of all removed nodes were prepared for pathological examination. FINDINGS: From the sentinel node, we could accurately predict axillary lymph-node status in 156 (97.5%) of the 160 patients in whom a sentinel node was identified, and in all cases (45 patients) with tumours less than 1.5 cm in diameter. In 32 (38%) of the 85 cases with metastatic axillary nodes, the only positive node was the sentinel node. INTERPRETATION: In the large majority of patients with breast cancer, lymphoscintigraphy and gamma-probe-guided surgery can be used to locate the sentinel node in the axilla, and thereby provide important information about the status of axillary nodes. Patients without clinical involvement of the axilla should undergo sentinel-node biopsy routinely, and may be spared complete axillary dissection when the sentinel node is disease-free.  相似文献   
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