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121.
M Ellmerer L Schaupp G Sendlhofer A Wutte GA Brunner Z Trajanoski F Skrabal P Wach TR Pieber 《Canadian Metallurgical Quarterly》1998,83(12):4394-4401
Open flow microperfusion and a novel calibration technique (ionic reference technique) were evaluated for the frequent measurement of the absolute lactate concentration in sc adipose tissue. Furthermore, the influence of the plasma insulin concentration on the lactate concentration of sc adipose tissue was investigated during hyperglycemia. Sixteen lean healthy young men participated in the studies. In the postabsorbtive state the mean sc lactate concentrations were 1.29 and 1.36 mmol/L for the ionic reference technique and the no net flux protocol, respectively (not significant, P > 0.05). The simultaneously measured arterialized plasma lactate concentration was significantly lower at 0.77 mmol/L (P < 0.05). Both the sc lactate concentration (1.8+/-0.33 mmol/L) and the plasma lactate concentration (0.96+/-0.03 mmol/L) were significantly elevated during a hyperinsulinemic euglycemic clamp experiment. During a hyperglycemic clamp experiment the sc lactate concentration reached a significantly elevated plateau (2.15+/-0.27 mmol/L) that was not influenced by the increasing plasma insulin concentration. It is concluded that 1) open flow microperfusion combined with the ionic reference technique enables frequent measurement of the sc lactate concentration; 2) sc adipose tissue is a significant source of lactate release in the postabsorbtive state as well as during hyperinsulinemic clamp conditions; and 3) insulin concentrations greater than 180 pmol/L have no further influence on adipocyte stimulation of sc adipose tissue with respect to lactate release. 相似文献
122.
Proactive interference (PI) has long been recognized as a major cause of forgetting. Two experiments were conducted that offer another look at the subject by providing a detailed analysis of recall latency distributions during the buildup of and release from PI. These functions were accurately characterized by the convolution of the normal and exponential distributions (viz., the ex-Gaussian), which previously has been shown to describe recognition latency distributions. Further, the fits revealed that the increase in recall latency associated with the buildup of PI results from a slowing of the exponential retrieval stage only. The same result was found even when a short retention interval was used (and recall probability remained constant). These findings suggest that free-recall latency may be a sensitive index of the increased search set size that has often been assumed to accompany the buildup of PI. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
123.
Statisticians typically recommend completely randomized experimental designs. The reasoning behind this advice is theoretically sound. Unfortunately, engineers who typically run industrial experiments frequently fail to recognize restrictions on randomization, i.e., split-plot experiments, and are often unaware of the risks associated with analyzing split-plot experiments as if they were randomized. Similarly, issues concerning the inference space of the experiment frequently are not given adequate consideration. Conversely, statisticians frequently are unaware that a restriction on randomization does not necessarily translate into less information than a completely randomized design.
In this paper, we discuss a proactive methodology for identifying and incorporating information concerning restrictions on randomization and inference space in industrial experiments. We also present the factor relationship diagram (FRD), a tool that assists engineers in the recognition of restrictions of randomization and guides the development of questions that encourage the experimenter to understand those sources of variation that may contribute to a lack of precision in a split-plot experiment or lack of repeatability in inference space different from that studied in the experiment. Examples that illustrate the use of the methodology and the FRD are included. 相似文献
In this paper, we discuss a proactive methodology for identifying and incorporating information concerning restrictions on randomization and inference space in industrial experiments. We also present the factor relationship diagram (FRD), a tool that assists engineers in the recognition of restrictions of randomization and guides the development of questions that encourage the experimenter to understand those sources of variation that may contribute to a lack of precision in a split-plot experiment or lack of repeatability in inference space different from that studied in the experiment. Examples that illustrate the use of the methodology and the FRD are included. 相似文献
124.
HH Brunner 《Canadian Metallurgical Quarterly》1998,87(3):57-60, 62-3
Under the provisions of the Health Insurance Law (KVG), the costs of preventive medicine are to be borne by the mandatory health insurance. Although it has been defined who shall be responsible for taking the necessary measures, concrete objectives have yet to be established. This is giving rise to difficulties in the implementation of the law. The author discusses basic questions relating to this situation: The nature of the preventive measures (GENOME Analysis), and the economic efficiency. An insight is also given into the work of the Preventive Medicine Services Subcommittee of the Federal Service-Providing Committee (Subkommission Pr?ventive Leistungen der Eidgen?ssischen Leistungskommission) and the criteria adopted. 相似文献
125.
126.
Doug Burch Jonathan W. Martin Mark R. VanLandingham 《Journal of Coatings Technology》2002,74(924):75-86
A heat and moisture transfer model was used to study weathering of polymeric materials, such as paint, asphalt, sealants,
plastics, textiles, and polymeric composites. Three damage indices, related to temperature changes, humidity changes, and
time of wetness, respectively, were introduced to quantify adverse effects of climate. The variation of these indices was
investigated for a hot and humid climate (Miami, FL) and a hot and dry climate (Phoenix, AZ). In addition, the relative effects
of solar radiation, surface wetting by rain and dew condensation, and variations in outdoor temperature and relative humidity
on the three damage indices were investigated.
100 Bureau Dr., Stop 8621, Gaithersburg, MD 20899-8621. 相似文献
127.
128.
129.
M Müller M Brunner R Schmid RM Mader J Bockenheimer GG Steger B Steiner HG Eichler B Bl?chl-Daum 《Canadian Metallurgical Quarterly》1998,58(14):2982-2985
The transfer of cytotoxic agents across the tumor endothelium into the interstitial tumor space is considered a critical step in clinical resistance of solid tumors to antineoplastic chemotherapy. However, experimental data on drug transfer from the blood into the interstitium of solid tumors are scarce. Therefore, in this study, we used an innovative technique, in vivo microdialysis, for measuring interstitial tumor pharmacokinetics and plasma-to-tumor transfer rates of methotrexate (MTX) in breast cancer patients. Microdialysis probes were inserted into the primary tumor and the periumbilical s.c. adipose layer of nine previously chemotherapy-naive breast cancer patients to monitor interstitial concentrations following i.v. administration of MTX (40 mg/m2) during a three-drug treatment regimen. Mean interstitial MTX load in breast tumors, expressed as area under curve (AUC), was 60 +/- 20% (mean +/- SE; coefficient of variation = 100%) of mean plasma MTX load. There was no correlation between plasma AUC and the AUC in the interstitial space of tumor tissue (P = 0.93). Not one of the parameters plasma, interstitial tumor load, and transfer rate of MTX to the interstitial space was associated with favorable clinical response. In conclusion, plasma levels of MTX are not predictive of intratumor levels. There is a high interindividual variability in transendothelial MTX transfer. Under the present conditions, access of MTX to the interstitial space is not a rate-limiting step for clinical response to chemotherapy. 相似文献
130.
A 27-year experience with 252 popliteal artery aneurysms in 167 patients is reviewed. Long-term results with respect to graft patency and limb salvage rates are analyzed. The results emphasize the importance of early surgical intervention and demonstrate the superiority of autologous saphenous vein over other graft materials. 相似文献