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1.
Sixty-two women (mean age 68.7 +/- 0.9 yr) with postmenopausal spinal osteoporosis were treated with cyclical etidronate therapy (400 mg for 2 weeks alternating with 12 weeks of 1 gm elemental calcium and 400 IU Vitamin D3) for a minimum of 2 yr. Bone mineral density (BMD) of the lumbar spine (g/cm2) increased significantly (p < 0.0001) after yr 1 (4.1 +/- 0.5 per cent) and yr 2 compared with yr 1 (2.2 +/- 0.5 per cent). The response rate was 89 per cent after yr 1 and 84 per cent after yr 2. BMD of the hip (30 patients) increased by 1.5 +/- 0.9 per cent after yr 1 and 5.5 +/- 1.1 per cent (p < 0.0001) after yr 2 when compared with baseline. The response rate was 63 per cent after yr 1 and 80 per cent after yr 2. Smaller numbers of patients continued with treatment up to 4 yr with no adverse long-term effects. 相似文献
2.
Voltage switching induced by long-wavelength infrared light from a CO2 laser was observed using a double-barrier resonant tunneling diode (RTD) biased in the bistable region and the intersubband transition (IT) between the quantum confined states. Possible optoelectronic and all-optical switching applications involving hysteresis are proposed and discussed 相似文献
3.
This project reports the publication of a variety of existing curricular resources for emergency medicine on the global Internet in a format that allows hypertext links between related material, timely updates, and end-user feedback. Curricular elements were converted to Hypertext Markup Language with extensive links between related content. The completed document contains instructions for curriculum development, specific curricula for subspecialty areas within a residency, reading lists for subspecialty curricula, banks of images, and board-type questions with answers. Users are provided with a mechanism to provide immediate feedback to section editors with suggestions for changes, including new references. Access to all or part of the document can be controlled via passwords, but is potentially available to anyone with an Internet connection and a World Wide Web browser. The document may by viewed on the World Wide Web at: http:@www.brown.edu@Administration@emergency_Medicine@ curr.html. 相似文献
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5.
Predicted that high self-esteem Ss (HSEs) would rationalize an esteem-threatening decision less than low self-esteem Ss (LSEs), because HSEs presumably had more favorable self-concepts with which to affirm, and thus repair, their overall sense of self-integrity. This prediction was supported in 2 experiments within the "free-choice" dissonance paradigm: one that manipulated self-esteem through personality feedback and the other that varied it through selection of HSEs and LSEs, but only when Ss were made to focus on their self-concepts. A 3rd experiment countered an alternative explanation of the results in terms of mood effects that may have accompanied the experimental manipulations. Results were discussed in terms of the following: (1) their support for a resources theory of individual differences in resilience to self-image threats—an extension of self-affirmation theory, (2) their implications for self-esteem functioning, and (3) their implications for the continuing debate over self-enhancement vs self-consistency motivation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
W Steele 《Journal of dairy science》1985,68(6):1409-1415
Intakes of grass silage and yield and composition of milk were examined in cows given high-protein diets to which two quantities of soybean oil had been added either as intracellular or extracellular inclusions. Adding extra protein to the diet did not prevent reduction of dry matter intakes of forage when soybean oil was added to the diet of cows. There is a fundamental difference in the mechanism by which high-starch diets reduce intake of forage dry matter from that of high-oil diets. In diets containing extracellular unsaturated oils, concentration of oil in the total ration, not the amount of oil per se, is the primary determinant reducing milk fat percentage. 相似文献
7.
Optoelectronic properties of asymmetrically strained II-VI CdZnTe single-quantum-well structures grown by molecular-beam epitaxy are reported. Indium doping CdZnTe n-type using a two-dimensional electron gas heterostructure achieved a carrier mobility of 5000 cm2·V-1 s-1 at 40 K. A shallow donor ionization energy of 14.5 meV was determined from Hall effect measurements. Fabrication of a large-area-mesa heterostructure device allowed us to investigate exciton absorption of the mixed type-I and type-II single quantum well. Control of the electron concentration in the quantum well allows optical absorption modulation using both the quantum-confined Stark effect (QCSE) and phase-space absorption quenching. Separation of electron and hole photocurrents in different layers is demonstrated and results in photogain. A heavy-hole red-shift of 9.9 meV/V due to the reverse QCSE is reported 相似文献
8.
Adhesive interactions between leukocytes and endothelium are required for subsequent leukocyte extravasation toward inflammatory sites. Understanding the possible kinetic expression of vascular cell adhesion molecule-1 (VCAM-1) in the middle ear cavity during an inflammatory cascade in vivo may be important for clarifying local immunological responses in otitis media. Two inflammatory models were produced in the rat and involved acute middle ear mucosal and cutaneous inflammation induced after inoculation or intradermal injection of lipopolysaccharide (LPS). After intravenous injection of both 125I-labeled anti-VCAM-1 and 131I-labeled control monoclonal antibody (mAb), the kinetic expression of VCAM-1 in the middle ear and skin was assessed by local radionuclide uptake. The biodistribution of an 125I-labeled anti-VCAM-1 mAb as a potential detector of focal inflammation was examined in normal rats. Both inflammatory lesions were characterized by early and sustained (up to 24 h) expression of VCAM-1, with maximal expression at 4 h after LPS stimulation. The kinetics of VCAM-1 expression was similar among the middle ear mucosa or skin specimens studied and different stimulation methods. A similar biodistribution and clearance of radioactivity between 125I-labeled anti-VCAM-1 mAb and 131I- or 99mTc-labeled control mAb were observed. The present result suggest that functional VCAM-1 induced by LPS is expressed in both middle ear tissue and skin lesions and may play a role in the initial stage of inflammatory response produced. Although VCAM-1 upregulation is a very early event in the inflammatory cascade, 125I-labeled anti-VCAM-1 mAb may be useful for the early detection of focal inflammation in the middle ear. 相似文献
9.
A T-network model for the determination of the electrode impedances in a three electrode solid state electrochemical cell is postulated and discussed. The model is applied to a Li solid battery where the electrolyte is the polymer (PEO)8LiCF3SO3 and the positive electrode is the insertion electrode V6O13 + x. The Li metal reference electrode is found to have an impedance considerably greater than that of the working (V6O13 + x) or the counter electrode (Li). The significance of these impedances is discussed in relation to the geometry and construction of solid electrolyte cells, and to their suitability for potentiostatic measurements. 相似文献
10.
Kevin Steele 《软件》2008,(3):20-22
更换整机上模块的能力,可以在保证系统整体功能不变的基础上增减部分功能,以节约成本。随着半导体产业成本不断上涨,竞争日趋激烈,生产商们在保证产量最大化的同时,也绞尽脑汁提高产品质量。因此,他们需要灵活的设备以满足其快速升级和降低成本的要求。提高产出通常以每单元小 相似文献