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1.
The state of Oregon decided to cover all potentially eligible Medicaid citizens to 100% of poverty. Previously, Oregon had covered persons up to 67% of poverty. In order to keep overall program costs in check. Oregon decided to limit the number of services that its Medicaid program would cover. Oregon's normative choice was to contain program costs by covering all eligible persons up to 100% of poverty, while at the same time uniformly limiting access to certain services for everyone in the overall group of eligible persons. The state developed a prioritization list of medical services and priced the components on the list. The amount of money ultimately available for the Medicaid program was a political decision informed by data about the cost of different services and influenced by the priorities set through an independent process of priority-setting. Physicians were asked to determine what works medically, how well it works, and what benefits accrue to patients. Recognizing that physician perspectives on efficacy might vary from patients' perspectives on valuation of benefits, Oregon's planners developed a method for valuing medical outcomes that stemmed from particular medical interventions. This blend of medical fact and value to patients allowed for comparing valuations by introducing cost considerations. Condition-treatment (CT) pairs linked a medical condition with one or more courses of treatment. The goal was to determine the likely incremental medical benefit from a given treatment. In addition, Oregon developed a Quality-of-Well-Being scale to determine the net patient benefit from medical intervention and used a telephone survey to value that net benefit. A cost-benefit ratio was derived, and a prioritization of CT pairs was developed. The article analyzes and evaluates Oregon's use of cost-benefit calculations in the allocation of Medicaid funds, noting that Oregon itself backed away from many of the implications of its cost-benefit analysis and that the Americans with Disabilities Act has constrained use of quality-of-life judgments in Medicaid resource allocation decision-making.  相似文献   
2.
BACKGROUND: Recent studies in patients with previously untreated T1 and T2 squamous cell carcinoma (SCC) of the tongue and floor of the mouth have shown a relationship between tumor thickness, neck metastasis, and survival. Our study was conducted to determine the indication of elective neck dissection in patients with early oral cavity SCC. PATIENTS AND METHODS: Sixty-seven patients were stratified by stage (T1 and T2 NO), and those in each stage were randomized to receive one of two types of treatment; resection alone (RA) or resection plus elective supraomohyoid neck dissection (RSOND). Fifty-two patients (78%) were men and 15 (22%) were women. The median age was 57 years old (range 34 to 95). RESULTS: Twenty-six (39%) patients had tumor in the floor of the mouth and 41 (61%), in the tongue. Using the criteria of the Union Internationale Contre le Cancer (UICC), 1987, we classified 31 tumors (46%) as T1 lesions and 36 (54%) as T2 lesions. Thirty patients had a tumor thickness < or = 4 mm and 37 had a tumor thickness > 4 mm. Thirty-three (49%) patients were treated with RA, and 34 patients (51%) were treated with RSOND. Seven (21%) patients of the RSOND group had occult cervical metastasis. There were recurrences in 14 (42%) patients of the RA group and 8 (24%) patients of the RSOND group. The disease-free survival rates at 3.5 years for RA and RSOND patients were 49%, and 72%, respectively. The impact of sex, age, site, cancer stage, and tumor thickness was assessed by the Mantel-Haenszel chi-square procedure. Later stage (P = 0.05) and increased tumor thickness (P = 0.005) were significantly associated with treatment failures. CONCLUSION: Neck dissection remains mandatory in the early stage of oral SCC, because of better survival rates compared to RA and the poor salvage rate. In particular, patients with tumor thickness > 4 mm treated with RSOND had significant benefit on disease-free survival.  相似文献   
3.
The social environment and normative structure surrounding drinking have a reciprocal relationship in determining adolescent drinking patterns in high school and college.  相似文献   
4.
Organometal perovskite single crystals have been recognized as a promising platform for high-performance optoelectronic devices, featuring high crystallinity and stability. However, a high trap density and structural nonuniformity at the surface have been major barriers to the progress of single crystal-based optoelectronic devices. Here, the formation of a unique nanoisland structure is reported at the surface of the facet-controlled cuboid MAPbI3 (MA = CH3NH3+) single crystals through a cation interdiffusion process enabled by energetically vaporized CsI. The interdiffusion of mobile ions between the bulk and the surface is triggered by thermally activated CsI vapor, which reconstructs the surface that is rich in MA and CsI with reduced dangling bonds. Simultaneously, an array of Cs-Pb-rich nanoislands is constructed on the surface of the MAPbI3 single crystals. This newly reconstructed nanoisland surface enhances the light absorbance over 50% and increases the charge carrier mobility from 56 to 93 cm2 V−1 s−1. As confirmed by Kelvin probe force microscopy, the nanoislands form a gradient band bending that prevents recombination of excess carriers, and thus, enhances lateral carrier transport properties. This unique engineering of the single crystal surface provides a pathway towards developing high-quality perovskite single-crystal surface for optoelectronic applications.  相似文献   
5.
为解决扭杆弹簧热处理这一关系到扭杆产品质量和产量、节能降耗的关键技术,给出了扭杆弹簧退火热处理微机控制系统框图和调功电路,分析了系统工作原理,简化了数学模型以及程序设计中对PID参数的处理.  相似文献   
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Two patients presented with a tumor involving mainly the supplementary motor area or the premotor cortex. Shortly after tumor resection, each developed transient impairment of voluntary movements. An electromyogram, with the skin electrodes placed over the muscles of the upper arms and forearms, demonstrated aberrant ipsilateral, contralateral or bilateral muscle activation during unilateral motor tasks in both patients. The bilateral activation was more prominent in the patient who had an intact dominant hemisphere. The present study suggests for the first time the importance of non-primary motor areas of the human brain in activating the proper set of muscles on the proper side of the body.  相似文献   
8.
In adult gastric epithelium, gastrin and somatostatin regulate parietal cell acid secretion; however, their expression and function in the fetus are largely unknown. We defined the developmental expression of gastrin and somatostatin in the fetal rabbit stomach and determined their effects on fetal acid secretion. To define peptide expression, fetuses from 12 time-mated New Zealand white rabbit does were analyzed at successive ages during the third trimester (term is 31 days). Peptides were extracted from fetal gastric tissue by boiling in water and then in acetic acid. Amidated gastrin and somatostatin levels were measured by radioimmunoassay using antisera 1296 for gastrin and 8402 for somatostatin. To determine the effects of gastrin and somatostatin, pentagastrin (64 microg/kg/hr) or octreotide (35 microg/kg/hr) were infused intravenously in conscious pregnant rabbits at 28 days of gestation for 3 hr. Fetuses (n = 45) were harvested and gastric acid was titrated with 0.02 N NaOH. Gastrin and somatostatin tissue content were 12 +/- 3 and 51 +/- 6 pmol/g at gestational day 20, respectively, and increased to 146 +/- 10 and 162 +/- 5 pmole/g by day 30 (P < 0.05). Between days 24 and 26, when gastric acid was first detectable, the molar ratio of somatostatin to gastrin decreased from 5.0 +/- 1.0 to 1.1 +/- 0.1 (P < 0.05). Fetal gastric acid content (micromole) was 28.5 +/- 1.7 in controls, 27.5 +/- 1.9 with pentagastrin treatment, and 15.8 +/- 1.4 micromole with octreotide (P < 0.05). In summary, 1) In fetal gastric tissue, gastrin increased 12-fold and somatostatin increased 3-fold between days 20 and 30 of gestation. 2) The decreased ratio of somatostatin to gastrin between days 24 and 26 of gestation coincides with the onset of fetal gastric acid secretion in the fetal rabbit. 3) Maternal administration of octreotide inhibited fetal gastric acid content; however, pentagastrin had no effect. We conclude that, in the fetal rabbit stomach, the relative expression of gastrin and somatostatin may regulate the onset of parietal cell acid secretion.  相似文献   
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10.
In perfused rat skeletal muscle (hindlimb), capsaicin either stimulates (submicromolar concentrations) or inhibits (micromolar concentrations) oxygen consumption (VO2). Both VO2 effects are associated with vasoconstriction, evident as an increase in perfusion pressure (PP), under constant flow. We have proposed that these effects are mediated by two vanilloid receptor subtypes: VN1 (stimulation of VO2) and VN2 (inhibition of VO2) (; ). In the present study, the role of capsaicin-sensitive neurons and sensory neuropeptides in the VN1/VN2 receptor actions of capsaicin was investigated. The observed maximum stimulation of VO2 by capsaicin (0.4 microM; DeltaVO2, 1.35 +/- 0.14 micromol g-1 h-1) was accompanied by mild vasoconstriction (DeltaPP, 5.8 +/- 0.6 mm Hg). In contrast, 2 microM capsaicin produced strong inhibition of VO2 (DeltaVO2, -2.25 +/- 0.23 micromol g-1 h-1) with pronounced vasoconstriction (DeltaPP, 28.0 +/- 1.3 mm Hg). VO2 stimulation was significantly inhibited (P <.05) by the selective NK1 receptor antagonist CP-99994 (1 microM) and the NK2 receptor antagonist SR 48968 (1 microM) (by 42% and 51%, respectively), but PP was not altered. Infused SP and neurokinin A (NKA) stimulated VO2 (observed maximum DeltaVO2, 0.52 +/- 0.06 and 0.53 +/- 0.08 micromol g-1 h-1, respectively; EC50 values, 269 +/- 23 and 21.2 +/- 3.0 nM, respectively) and induced mild vasoconstriction (4.30 +/- 0.33 and 6. 75 +/- 1.18 mm Hg, respectively; EC50 values, 352 +/- 25.7 and 25.5 +/- 2.7 nM, respectively). Neurokinin B (NKB) also stimulated VO2 (maximum not determined) and vasoconstriction (maximum DeltaPP, 3.40 +/- 0.25 mm Hg; EC50, 34.4 +/- 5.2 nM). The rank order of potency for the tachykinins in this preparation was NKA > NKB > SP, which suggests stimulation primarily of NK2 receptors. Although infused calcitonin gene-related peptide (CGRP) did not alter hindlimb VO2 or PP, the selective CGRP antagonist CGRP(8-37) markedly potentiated the inhibition of VO2 produced by 1 microM capsaicin (84%) and the maximum capsaicin-induced vasoconstriction (57%), which indicates that endogenously released CGRP may act as a vasodilator. Hindlimbs perfused 1 day after capsaicin pretreatment showed attenuation of capsaicin-induced (0.4 microM) stimulation of VO2 (92%) (P <.05) and vasoconstriction (64%), but this returned to normal after 7 days. The inhibition of VO2 by 1 microM capsaicin was significantly (P <. 05) enhanced 7 and 14 days after pretreatment (66% and 140%, respectively), as was the maximum vasoconstriction (64% and 68%, respectively). These data suggest that capsaicin-sensitive neurons, presumably via release of SP and NKA, are involved in VN1 responses and that capsaicin pretreatment potentiates VN2 responses, either by depletion of CGRP reserves or by upregulation of putative VN2 receptors.  相似文献   
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