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1.
We are reporting on a series of two patients with end‐stage renal disease on hemodialysis, presented for surgical parathyroidectomy secondary refractory hyperparathyroidism. Both patients had failed maximized medical managements, including higher‐than‐usual doses of the calcimimetic cinacalcet (270 and 180 mg/day, respectively). On physical exam, both patients had marked symmetrical craniofacial hypertrophy with coarse distortion of facial features, similar in appearance to past reports of Sagliker syndrome. On X‐ray and computed tomographic exam, they had peculiar areas of bone absorption on the skull, imitating the radiologic appearance of multiple myeloma. Bone biopsy of the maxilla, however, did not show the expected brown tumor, but rather described only fibrosis and reactive bone formations. This phenotype developed while being on cinacalcet, progressed despite escalation of therapy, and improved only after parathyroidectomy. Both patients developed massive “hungry bone syndrome” after parathyroidectomy necessitating prolonged IV calcium infusion. This pattern of severe facial distortion likely represented an adverse consequence of severe tertiary hyperparathyroidism, along with supraphysiologic dose of cinacalcet administration and 25‐hydroxy vitamin D deficiency in sensitive individuals. The genetic base of this observation remained unexplained.  相似文献   
2.
This paper investigates cognitive and physiological precursors of orthostatic panic (OP), that is, panic upon standing, which is a key complaint among traumatized Cambodian refugees. Prior research links OP to hypotension (lower blood pressure) and catastrophic cognitions. A clinical sample of 102 Cambodian refugees were assessed for posttraumatic stress disorder (PTSD), recent OP attacks, and anticipatory anxiety before engaging in an orthostatic challenge (OC) task during which they were monitored for blood pressure. After the task, they were assessed for OC-induced culture-related catastrophic cognitions, flashbacks, and panic attacks. We found that participants with recent OP (n = 60) had more PTSD, greater anticipatory anxiety before the OC, a larger drop in systolic blood pressure during the OC, more OC-induced catastrophic cognitions and flashbacks, and more severe OC-induced panic attack symptoms. Regression models showed that the severity of OC-induced panic symptoms was predicted by the magnitude of SBP drop and mediated by more severe catastrophic cognitions and flashbacks. Implications of the findings for cross-cultural psychopathology research and the treatment of both panic and PTSD in Cambodian refugees are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
Bracken presents a serious environmental problem in many regions of the world and remote sensing offers the potential of monitoring the invasion and management of this plant. This study evaluates this potential by reporting the results of an investigation of the relationships between the biophysical properties of a bracken canopy and its spectral reflectance and how such relationships are effected by view angle. An experiment was carried out through the bracken growing season at sites in West Sussex, UK. In the principal plane of the Sun, red reflectance becomes lower and relatively less variable with view angle as the canopy develops, while near-infrared reflectance increases and becomes relatively more variable with view angle. As Leaf Area Index (LAI) increases, the variability of the Normalized Difference Vegetation Index (NDVI) with view angle decreases, while the simple ratio vegetation index (SR) behaves in almost the opposite manner. Polar plots, illustrating full directional reflectance distributions, reveal that as the canopy develops the hot spot in red reflectance at the retro-solar angle diminishes, to be replaced by enhanced red reflectance at high zenith angles in the forward-scatter direction. Near-infrared reflectance behaves very differently, as a hot spot at the retro-solar angle becomes more pronounced as the canopy grows. The angular distribution of NDVI and SR varies markedly over the growing season, however both indices are well correlated with canopy biophysical properties for most view angles sampled, apart from the extreme off-nadir. Red edge position was largely insensitive to view angle, but had a good correlation with LAI, as did percenage reflectance at the red edge position.  相似文献   
4.
Smoothed Particle Hydrodynamics has been successfully used for various fluid-dynamics problems, such as breaking-waves, flooding etc., since it was originally proposed. While the Lagrangian approach is naturally suitable for free-surface flows, enforcing boundary conditions and poor approximations in the presence of discontinuities in the solution are major difficulties with the method. In this paper we present an enhanced conservative Godunov SPH based on the work of Inutsuka [S. Inutsuka, Reformulation of smoothed particle hydrodynamics with Riemann solver, Journal of Computational Physics 179 (2002) 238–267] that accurately resolves discontinuities without the need to use artificial viscosity, preserves partition of unity everywhere in the domain, correctly and flexibly enforces necessary essential and frictional slip boundary conditions to approximately solve free-surface granular flows. The development is motivated by the need to improve upon depth averaged grid based models of large scale debris flows and avalanches often characterized as granular flows. Simple validation of the results is obtained by comparison to table-top experiments.  相似文献   
5.
Psychologically traumatized people exhibit delayed color naming of trauma words in the emotional Stroop task. Four groups of participants were asked to color name positive words, neutral words, and trauma words; these groups included 15 women who believed that they harbored repressed memories of childhood sexual abuse (CSA), 13 women who reported recovered memories of CSA, 15 women who had never forgotten their CSA, and 12 women who had never been abused. Repressed-memory participants exhibited patterns of interference indistinguishable from those of the nonabused control group participants. Irrespective of group membership, the severity of self-reported posttraumatic stress disorder symptoms was the only significant predictor of trauma-related interference, r(48)?=?.30?, p?  相似文献   
6.
The authors used a directed-forgetting task to investigate whether psychiatrically impaired adult survivors of childhood sexual abuse exhibit an avoidant encoding style and impaired memory for trauma cues. The authors tested women with abuse histories, either with or without posttraumatic stress disorder (PTSD), and women with neither abuse histories nor PTSD. The women saw intermixed trauma words (e.g., molested), positive words (e.g., confident), and categorized neutral words (e.g., mailbox) on a computer screen and were instructed either to remember or to forget each word. Relative to the other groups, the PTSD group did not exhibit recall deficits for trauma-related to-be-remembered words, nor did they recall fewer trauma-related to-be-forgotten words than other words. Instead, they exhibited recall deficits for positive and neutral words they were supposed to remember. These data are inconsistent with the hypothesis that impaired survivors exhibit avoidant encoding and impaired memory for traumatic information.  相似文献   
7.
8.
A two-fluid model for avalanche and debris flows   总被引:1,自引:0,他引:1  
Geophysical mass flows--debris flows, avalanches, landslides--can contain O(10(6)-10(10)) m(3) or more of material, often a mixture of soil and rocks with a significant quantity of interstitial fluid. These flows can be tens of meters in depth and hundreds of meters in length. The range of scales and the rheology of this mixture presents significant modelling and computational challenges. This paper describes a depth-averaged 'thin layer' model of geophysical mass flows containing a mixture of solid material and fluid. The model is derived from a 'two-phase' or 'two-fluid' system of equations commonly used in engineering research. Phenomenological modelling and depth averaging combine to yield a tractable set of equations, a hyperbolic system that describes the motion of the two constituent phases. If the fluid inertia is small, a reduced model system that is easier to solve may be derived.  相似文献   
9.
Notched impact fracture experiments have been conducted on specimens of polycarbonate in three different conditions, (a) as received, (b) annealed at 125° C, and (c) electron beam irradiated to reduce the molecular weight. By consideration of the behaviour of a wide range of notch geometries four different failure modes were identified which were present in different proportions for each material. (1) Razor notched specimens failed in a completely brittle manner, well described by linear elastic fracture mechanics. (2) Small notch tip radii specimens failed in an apparently brittle manner through the formation of a single craze. (3) Some intermediate notch tip radii specimens failed in a predominantly brittle manner with small shear lips indicative of plane stress yielding. A fracture mechanics approach was used here, the measured toughness correlating with the extent of plane stress yielding. (4) Fully ductile failure was observed for large notch tip radii for all materials. It has been established that the embrittlement of polycarbonate caused by annealing is due to an increase in the yield stress, whereas that caused by reducing the molecular weight is due to a reduction of the crazing stress. In both cases, more specimens of intermediate notch tip radius are caused to fail in the low energy brittle mode designated (2) above. By varying the yield stress and crazing stress independently we have thus been able to distinguish clearly how both influence the brittle-ductile transition.  相似文献   
10.
ABSTRACT: The American diet is high in calories, but low in nutrients. To help consumers obtain more nutrition from the calories they consume, research is underway to develop a nutrient profiling approach that can be used to evaluate individual foods and help people build healthful diets. A nutrient profiling system that rates individual foods based on their nutrient content needs to be both science‐driven and user‐friendly, allowing consumers to make more healthful food choices within and across all the food groups. A recent survey, commissioned by the Nutrient Rich Food Coalition, reveals that the majority of consumers and nutrition professionals believe that better information about a food's total combined nutrient content would be effective and useful in helping them make more nutrient‐rich food choices.  相似文献   
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