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1.
PURPOSE: Percutaneous transluminal angioplasty with stenting (PTAS) of the carotid artery has been advocated as an alternative treatment for high-grade stenosis. Rationale for this approach includes less morbidity, shorter recovery, and lower cost when compared with carotid endarterectomy (CEA). METHODS: The clinical results and hospital charges of patients who underwent elective treatment for carotid stenosis were reviewed. During a concurrent 14-month period, 218 patients were admitted 229 times for 234 procedures for the treatment of 239 carotid bifurcation stenoses, 109 by PTAS and 130 by CEA. Hospital charges were reviewed for each hospitalization and were categorized according to radiology, operating room, cardiac catheterization laboratory, and all other hospital charges. RESULTS: The combined incidence of postprocedure strokes and deaths were: PTAS, eight strokes (7.7%) and one death (0.9%); CEA, two strokes (1.5%) and two deaths (1.5%). Total hospital charges per admission for the two groups were $30,140 for PTAS and $21,670 for CEA. The average postprocedure length of stay for PTAS was 2.9 days (median, 2 days) and for CEA was 3.1 days (median, 3 days). Cardiac catheterization laboratory charges for the PTAS group were $12,968, whereas the operating room charges for the CEA group were $4263. When hospitalizations that were extended by complications were excluded, the average total charges for the PTAS group (n = 84) dropped to $24,848 (mean length of stay, 1.9 days) and for the CEA group (n = 111) to $19,247 (mean length of stay, 2.6 days). CONCLUSIONS: After evaluating hospital charges, PTAS for the treatment of carotid stenosis cannot currently be justified on the basis of reduced costs alone. With future cost-containing measures, total hospital charges can be reduced in both groups.  相似文献   
2.
The present study compared thein vitro hydrolysis of two 18:3n-6-rich oils—evening primrose oil (EPO) and borage oil (BO)—and different synthetic 18:3n-6-containing triacylglycerols (TG). Incubation of EPO and BO with pancreatic lipase lipolyzed 18:3n-6 from the TG species. The rate of lipolysis of TG species containing two or three molecules of 18:3n-6, which comprised 36% of total 18:3n-6 in BO and only 7% in EPO, was significantly slower than those containing only one molecule of 18:3n-6. This was found especially in those with two molecules of linoleic acid, which constituted 20% of total 18:3n-6 in BO, whereas over 80% were present in EPO. In a separate study, various synthetic 18:3n-6-containing TG were also subjected toin vitro hydrolysis by pancreatic lipase. Results showed that release of 18:3n-6 from thesn-1/sn-3 positions was significantly slower when two other stereospecific positions in the same TG molecule were occupied by either palmitic acid (16:0) or monounsaturated (18:1 and 20:1) fatty acids than when occupied by 18:2n-6. The rate of hydrolysis ofsn-2-γ-linolenyl-sn-1(3)-diacylglycerol to formsn-2-mono-γ-linolenyl glycerol was also significantly slower when both thesn-1 andsn-3 positions in TG molecules were occupied by either saturated fatty acids (16:0 and 18:0) or long-chain monounsaturated fatty acids than when occupied by 18:2n-6. These findings suggest that the stereospecific position of 18:3n-6 in TG molecules and the constituent of its neighboring fatty acids modulated availability of 18:3n-6 from 18:3n-6-containing TG or 18:3n-6-rich oils.  相似文献   
3.
A digital-image-processing algorithm is described for automatically measuring the diameters of cashmere-goat fibres from microscope images. A correction factor is used to remove bias when fibres are out of focus. Diameters are estimated to within a standard error of 4%.  相似文献   
4.
This article reports a systematic research effort aimed at establishing a normative database of thumb circumduction range of motion (ROM) and related kinematic characteristics in vivo while examining the effects of anthropometry, gender, and direction of rotation. Twenty-eight (14 men, 14 women) anthropometrically diverse participants performed maximum voluntary thumb circumductions as the trajectories of the surface markers placed on their thumb landmarks were recorded by an optoelectronic motion capture system. A globographic representation method was employed to model the measured marker trajectories, determining the center of rotation and central reference axes for thumb circumduction. Thumb ROM was quantified using (a) the joint sinuses expressing the thumb orientation change with respect to the reference axes and (b) cone volumes circumscribed by the thumb at the distal phalangeal, interphalangeal, and metacarpophalangeal levels. Data analyses resulted in statistical summaries of the derived kinematic and ROM measures with significant effects identified and regression equations predicting the cone volumes. Potential applications of this research include ergonomic design of hand-operated controls or devices and evaluation of thumb impairments or disorders.  相似文献   
5.
Canola meal is highly regarded as a component of animal feed with a high protein content and a desirable amino acid profile. The presence of some components, in particular glucosinolates, sinapine and fibre, affects the value of the meal and reduces the amount that can be used in animal feed formulations. Glucosinolates in traditional cultivars (rapeseed) had very high amounts and this severely limited the usefulness of the meal. Canola breeding programs have successfully reduced glucosinolate content to trace amounts. However sinapine remains at levels sufficiently high to cause problems, particularly in poultry feed. The relatively high fibre level in canola also reduces the value of the product for animal feed. This study has determined the level of sinapine, glucosinolates and fibre in current cultivars of canola in Australia to illustrate advances made by breeding programs and limitations which still remain to raise the usefulness of a potentially valuable feedstock. Although glucosinolate levels in meal were shown to have been reduced to 11 μmol/g in some cases, sinapine remained at traditional levels of about 12–15 g/kg and neutral detergent fibre levels were about 30–40%. These issues are important priorities for canola breeders.  相似文献   
6.
The spectral induced polarization (SIP) technique is a promising approach for delineating subsurface physical and chemical property changes in a minimally invasive manner. To facilitate the understanding of position and chemical properties of reaction fronts that involve mineral precipitation in porous media, we investigated spatiotemporal variations in complex conductivity during evolution of urea hydrolysis and calcite precipitation reaction fronts within a silica gel column. The real and imaginary parts of complex conductivity were shown to be sensitive to changes in both solution chemistry and calcium carbonate precipitation. Distinct changes in imaginary conductivity coincided with increased hydroxide ion concentration during urea hydrolysis. In a separate experiment focused on the effect of hydroxide concentration on interfacial polarization of silica gel and well-sorted sand, we found a significant dependence of the polarization response on pH changes of the solution. We propose a conceptual model describing hydroxide ion adsorption behavior in silica gel and its control on interfacial polarizability. Our results demonstrate the utility of SIP for noninvasive monitoring of reaction fronts, and indicate its potential for quantifying geochemical processes that control the polarization responses of porous media at larger spatial scales in the natural environment.  相似文献   
7.
This study examines the effects of the ratio of n−3/n−6 fatty acids (FA) on brain development in mice when longchain n−3 FA are supplied in the diet. From conception until 12 days after birth, B6D2F1 mice were fed liquid diets, each providing 10% of energy from olive oil, and a further 10% from different combinations of free FA concentrates derived from safflower oil (18∶2n−6), and fish oil (20∶5n−3 and 22∶6n−3). The range of dietary n−3/n−6 ratios was 0,025, 0.5, 1.0, 2.0, and 4.0, with an n−6 content of greater than 1.5% of energy in all diets, and similar levels of total polyunsaturated fatty acids (PUFA). In an additional group of ratio 0.5, 18∶2n−6 was partially replaced by its δ6 desaturation product, 18∶3n−6. Biochemical analyses were conducted on 12-day-old pup brains, as well as on samples of maternal milk. No obvious effects on overall pup growth and development were observed, apart from a smaller litter size at ratio 1. Co-variance analysis indicated that increasing the n−3/n−6 ratio was associated with slightly smaller brains, relative to body weight. We found that 18∶2n−6 and 20∶5n−3 were the predominant n−6 and n−3 FA in the milk; in the brain these were 20∶4n−6 and 22∶6n−3, respectively. Increasing dietary n−3/n−6 ratios generally resulted in an increase in n−3 FA, with a corresponding decrease in n−6 FA. The n−3/n−6 ratio of the milk lipids showed a strong linear relationship with the diet, but in the brain the rate of increase tended to decrease beyond 0.5 (phosphatidylcholine, PC) and 0.25 (phosphatidylethanolamine, PE), such that there was a significant quadratic contribution to the relationship. The partial replacement of dietary 18∶2n−6 with 18∶3n−6 raised levels of 20∶4n−6 in milk, brain PC, and brain PE. These results indicate that the n−3/n−6 ratio of the phospholipids in the developing mouse brain responds maximally to maternal dietary long-chain n−3/n−6 ratios of between 0.25 and 0.5.  相似文献   
8.
Effective leadership requires relationship skills such as – problem solving conflict management, motivation, communication, and listening [Yukl, G. A. (1998). Leadership in organizations. Upper Saddle River, NJ: Prentice Hall]. Arguably, nothing is more important to a leader than the skills involved in communicating one’s intent to followers, for it is only through effectively transmitting intent that followers may understand and then execute the goals of the team and leader. The modern work-world is dominated by computer-mediated communication, and this communication is the bread and butter of virtual teams; however, simple transmission of information from point A to point B is not enough – the virtual environment presents significant challenges to effective communication. In this paper we review issues related to virtual teams and developments in multimodal displays that allow teams to communicate effectively via single or multiple modalities (e.g., visual, auditory, tactile). This discussion is grounded in guiding principles for design and use of information displays that were identified and culled based on multiple review criteria from an extensive review of the literature. We present an applied example of the utility of these guiding principles for multimodal display design, in the context of communicating a leader’s presence to virtual followers via commander’s intent.  相似文献   
9.
Past research suggests that a categorical event is perceived to be more likely if its subcases are explicitly delineated or “unpacked.” In 6 studies, we find that unpacking can often make an event seem less likely, especially when the details being unpacked are already highly accessible. Process evidence shows that the provision of greater detail accompanying unpacking reduces the simplicity of an event and that this dysfluency is used as a negative cue for likelihood. This work establishes processing fluency as a mechanism that opposes the other effects of unpacking, such as enhanced accessibility. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
10.
As part of a U.S. Bureau of Mines program directed towards understanding the formation and elimination of “type 1” hard alpha defects in titanium alloy ingots, titanium nitride additions of 6 mm (0.25 in.) nitrided sponge particles or air-contaminated sponge were studied. The results reinforce the contention that a primary melting process with a longer residence time than consumable electrode vacuum arc melting is needed. Such a process would ensure dissolution of high nitrogen defects introduced from the raw materials making up the initial ingot or from defects created in processing.  相似文献   
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