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排序方式: 共有1068条查询结果,搜索用时 15 毫秒
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Suicide rates in Hong Kong increased with age, and the highest suicide rate occurred among the oldest age groups. Hong Kong has one of the highest elderly suicide rates in the world. The elderly suicide rate was four to five times above the average. Furthermore, gender differences were observed among different marital status groups. For example, single males had a much higher rate than single females and married males had a higher rate than their widowed counterparts. The suicide rate for an economically inactive person was six times higher than for an active one. Jumping has become increasingly common and seems to substitute for other methods of suicide. Winter months and the Chinese New Year period had the lowest suicide occurrence. Some explanations are given. 相似文献
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Mien Yip Jon Mohle & J. E. Bolander 《Computer-Aided Civil and Infrastructure Engineering》2005,20(6):393-407
Abstract: Irregular lattices are used to model three-dimensional (3D) structural components consisting of a bulk material, curvilinear reinforcement, and their interface. Domain discretization is highly automated and involves the semi-random placement of nodal points within the domain, followed by Voronoi tessellation of the nodal point set. A technique is given for the Voronoi partitioning of nonconvex domains. For discretizing nonconvex domains, and for effective gradation of nodal point density, a minimum allowable distance between nodes is maintained and the domain is saturated with nodes. To accelerate this computationally expensive operation, a partitioned domain search is used during the filling process. Reinforcement, and its interface with the bulk material, are discretely modeled and freely positioned in the domain, irrespective of the geometry of the irregular lattice representing the bulk material. This method of discretization facilitates model construction, results interpretation, and possible revisions to the model. While the focus is on automated domain discretization and the modeling of reinforcement, elastic properties of the model are demonstrated through examples involving nodal stress calculations and deflection analyses of prestressed concrete beams. 相似文献
97.
KM Yip 《Canadian Metallurgical Quarterly》1997,116(4):229-232
OBJECTIVE: To evaluate the ocular toxicity of intravitreous octreotide. DESIGN: New Zealand white rabbits weighing approximately 2 kg were given 5 mg (group 1, two eyes), 2 mg (group 2, four eyes), 1 mg (group 3, four eyes), 0.5 mg (group 4, two eyes), 0.3 mg (group 5, two eyes) or 0.1 mg (group 7, two eyes) of octreotide acetate, two doses of 0.3 mg 1 week apart (group 6, four eyes) or 0.1 mL of balanced salt solution (group 8 [control group], two eyes). OUTCOME MEASURES: Findings on clinical examination and electroretinography, performed before and 10 days after injection, and on light microscopy. RESULTS: Cataracts developed in groups 1 and 2. No clinical changes were found in groups 3 to 8. Electroretinography showed various degrees of decrease in the b-wave amplitude in groups 1 and 2; the results were normal in groups 3 to 8. Histologic examination showed macrophage and monocyte infiltration in the vitreous and retina in group 1. No histologic change was seen in the eyes in groups 2 to 8. CONCLUSIONS: Octreotide injected intravitreally is safe at dosages of 1 mg or less. 相似文献
98.
We report a molecular dynamics simulation study of stress–strain response of single crystal α-quartz under uniaxial compression using the interatomic potential of van Beest et al. [Phys. Rev. Lett. 64 (1990) 1955]. The results at 1073 K shows an abrupt onset of large deformation of 14 GPa and subsequent time-dependent evolution of an “amorphous” structure with near-planar character. We regard this to be a lattice instability leading to structural failure, to be distinguished from a similar instability observed under hydrostatic loading which results in a phase change. The simulation results allow us to suggest new interpretations of experimental observations with regard to the formation of thin zones of isotropic (glassy) material along faults and a possible mechanism for planar fracture. 相似文献
99.
S de Pee MW Bloem J Gorstein M Sari Satoto R Yip R Shrimpton Muhilal 《Canadian Metallurgical Quarterly》1998,68(5):1068-1074
Food-based approaches for controlling vitamin A deficiency and its consequences, such as increased mortality, more severe morbidity, and anemia, have become increasingly important, thus prompting a reassessment of the relation between vitamin A intake and status. A nutrition surveillance system in Central Java, Indonesia, assessed the vitamin A intake and serum retinol concentration of women with a child < or =24 mo old with a semiquantitative 24-h recall method that categorized vitamin A-containing foods into 3 categories of plant foods and into 2 categories of animal foods and identified portions as small, medium, or large. Median vitamin A intake was 335 retinol equivalents (RE)/d (n = 600) and vitamin A intake from plant foods was 8 times higher than from animal foods. Serum retinol concentration was related to vitamin A intake in a dose-response manner. The multiple logistic regression model for predicting the chance for a serum retinol concentration greater than the observed median (> or = 1.37 micromol/L) included physiologic factors, vitamin A intake from plant [odds ratio (95% CI) per quartile: 1st, 1.00: 2nd, 1.23 (0.75, 2.02); 3rd, 1.60 (0.97, 2.63); and 4th, 2.06 (1.25, 3.40)] and animal [1st and 2nd, 1.00; 3rd, 1.31 (0.86, 2.02); and 4th, 2.18 (1.40. 3.42)] foods, home gardening [(no, 1.00; yes, 1.71 (1.12, 2.60)], and woman's education level [< or =primary school, 1.00; > or =secondary school, 1.51 (1.02, 2.22)]. Despite the fact that plant foods contributed 8 times as much vitamin A as did animal foods, serum retinol concentrations did not reflect this large difference. Home gardening and woman's education level seemed to reflect longer-term consumption of vitamin A-rich plant and animal foods, respectively. 相似文献
100.
SA Rhone RS Hogg B Yip C Sherlock B Conway MT Schechter MV O'Shaughnessy JS Montaner 《Canadian Metallurgical Quarterly》1998,178(3):662-668
This study was undertaken to characterize predictors of response to double nucleoside combinations among 245 human immunodeficiency virus-infected persons initiating antiretroviral therapy. The median time for receiving antiretroviral therapy in this group was 6 months, and the plasma virus load was 58,000 copies/mL. The most commonly prescribed regimens were zidovudine/lamivudine (154 subjects, 63%) and stavudine/lamivudine (46 subjects, 19%). A total of 96 (39%) subjects had their virus load decrease to < 500 copies/mL after the initiation of therapy. Of the 245 study subjects, 102 (41.6%) had > or = 5 months of follow-up and two or more consecutive virus load determinations performed after the start of antiretroviral therapy. Multivariate analysis demonstrated that baseline virus load was the only significant factor associated with obtaining two or more plasma virus loads of < 500 copies/mL. Overall, these data demonstrate that dual nucleoside therapy (using currently licensed agents) cannot reliably achieve a high level of suppression of plasma virus load. 相似文献