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91.
The design and implementation of an automated tissue culture flask labeling, delivery, scraping, and retrieval system centered around the Cellmate cell culture robot is presented. Three new custom subsystems named FlaskMaster, FlaskLabeler, and FlaskScraper were created and integrated into the Cellmate robotic system. FlaskMaster is a centralized multi-axis robot with a surrounding enclosure that houses racks of stacked tissue culture flasks (size T-175). The FlaskMaster system interfaces externally with the Cellmate's conveyor system to deliver and retrieve flasks. FlaskLabeler is a print and apply system that labels flasks prior to transfer between FlaskMaster and the Cellmate. FlaskScraper is a scraping rod and blade assembly that was specifically designed for automated scraping of T-175 flasks. The combination of these systems allows for large-scale, unattended cell seeding and harvesting of cells from flasks. The addition of these new capabilities significantly reduces the manpower needed to operate the Cellmate. Moreover, these changes greatly improve the performance and capability of the stand-alone Cellmate system.  相似文献   
92.
Telehealth has many applications, including the education and training of health professionals. This article describes the use of advanced telecommunications technology to educate family nurse practitioners in rural areas of Kansas. Four Kansas universities use compressed video technology (an interactive audio and video system) to offer five common core courses in primary care to students enrolled in FNP programs at the respective institutions. Using technology to educate FNPs in rural communities has resulted in a greater percentage of graduates (approximately 67% of 258 graduates) going to work in rural underserved communities. In addition to learning the course content, students learn to use technology as a tool to access telehealth information and services Knowing how to use these technologies provides greater opportunities to rural health care providers, as well as the recipients of health care.  相似文献   
93.
The effect of dry corona and aqueous treatments on the hygral expansion of wool gabardine has been investigated. Increasing the severity of the corona treatment produced a concomitant reduction in the hygral expansion of the fabric. X-ray photoelectron spectroscopy has been used to study the chemical modification of the wool fibre surface.  相似文献   
94.
To investigate whether time-tradeoff utilities of survivors of myocardial infarction change over time and whether changes in utilities correlate with changes in functional status, the authors conducted serial interviews using a time tradeoff and three measures of functional status in a cohort of 67 patients who had recently had myocardial infarction. The patients were also asked to rate their overall health on a rating scale and were asked about chest pain, exercise status, and employment status. Each patient was interviewed two to five times over one and a half years. The mean (95% CI) time-tradeoff score for all patients was 0.88 (0.84, 0.93). Over a mean interval of 8.4 months, 28 (42%) patients changed Karnofsky scores, 28 (42%) changed Specific Activity Scale classes, and 11 (16%) changed New York Heart Association classes, with most changes representing improvements in functional status. Scores on the rating scale improved by a mean (95% CI) of 0.06 [(0.03, 0.10); p < 0.002], but scores on the time tradeoff remained stable, with a mean (95% CI) change of 0.03 [(-0.02, 0.08); p = NS]. Changes in time-tradeoff scores did not correlate with changes in Specific Activity Scale classes (Kendall's tau = 0.21), New York Heart Association classes (tau = -0.02), or Karnofsky scores (tau = 0.14); with changes on the verbal rating scale (R = 0.20); with changes in chest pain status (tau = -0.05), exercise status (tau = 0.11), or employment status (tau = 0.11); or with interim hospitalizations (tau = 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
95.
96.
Pre-eclampsia is suggested to be characterized by a functional imbalance between vascular prostacyclin and thromboxane A2 production. On the basis of this hypothesis it is attempted to correct this pathologic conditions by pharmacological manipulation with Trapidil, a triazolo pyrimidin derivative, because of its effects on the prostanoid metabolism. A prospective, randomized, double blind, placebo-controlled study was carried out to investigate Trapidil in the prevention of pregnancy-induced hypertension or pre-eclampsia. A total of 160 pregnant women with the risk to develop pre-eclampsia received Trapidil or placebo between week 24 and 38 of gestation. The number of patients in whom pregnancy-induced hypertension or pre-eclampsia developed was significantly lower in the Trapidil-treated (5.5%) compared with the placebo-treated group (14.1%). Additionally, a reduced risk of preterm deliveries and severe fetal growth retardation could be observed. In 7 patients with manifest pre-eclampsia or pregnancy-induced hypertension the circulating eicosanoid concentrations were determined before and during Trapidil medication. Trapidil was associated with an about twofold increase of 6-keto PGF1 alpha concentration in the peripheral venous blood, while the concentration of thromboxane A2 revealed no changes.  相似文献   
97.
98.
Precision-cut liver slices prepared from Aroclor 1254 pretreated male rats were used to investigate the metabolism of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). The acetyltransferase and sulfotransferase inhibitors, pentachlorophenol (PCP) and 2,6-dichloro-4-nitrophenol (DCNP), and the cytochrome P450 inhibitor, alpha-naphthoflavone (ANF), were used to modulate PhIP metabolism and DNA and protein adduct formation. PCP and DCNP had similar effects on the formation of some PhIP metabolites. PCP and DCNP decreased the formation of 4'-(2-amino-1-methylimidazo[4,5-b]pyrid-6-yl)phenyl sulfate (4'-PhIP-sulfate) and 2-(hydroxyamino)-1-methyl-6-phenylimidazo[4,5-b]pyridine (N-hydroxy-PhIP)-glucuronide to 10% and 55% of controls, respectively. 2-Amino-1-methyl-4'-hydroxy-6-phenylimidazo[4,5-b]pyridine (4'-hydroxy-PhIP) was increased by 50% relative to control levels due to PCP and DCNP treatment. PCP and DCNP had different effects on the formation of other PhIP metabolites. Metabolite formation as percent of control for the uncharacterized metabolite, 'Peak A', was 50% and 100% in incubations with PCP and DCNP, respectively. Formation of 4'-hydroxy-PhIP-glucuronide was decreased to 10% of controls with PCP and increased to 147% of controls with DCNP. PCP and DCNP had no effect on the formation of an unidentified metabolite, 'Peak B'. ANF decreased metabolite formation by 60-95%. None of the enzyme inhibitors had a statistically significant effect on PhIP-DNA binding. Covalent binding of PhIP to protein was slightly decreased in incubations containing DCNP or PCP. The lack of significant changes in covalent binding to either DNA or protein suggests that additional pathways may be important in PhIP bioactivation in rat liver slices. With ANF, there was a significant decrease (35%) in protein binding. These observations on the effects of PCP, DCNP and ANF on PhIP metabolism as well as on covalent binding of PhIP to tissue macromolecules are in close agreement with what was reported earlier in hepatocytes. This indicates that tissue slices from various target tissues for tumorigenesis will be a useful in vitro tool for future studies on heterocyclic amine metabolism. This study provides another important example of the utility of precision-cut tissue slices to investigate xenobiotic metabolism and toxicity.  相似文献   
99.
Acoustic emissions obtained from polymers under stress have been subjected to various mathematical analyses with the objective of relating the observed signals to accompanying chemical and physical changes in the polymer. The following methods have been investigated: frequency analysis, autocor-relation analysis, cepstrum analysis and cluster analysis (pattern recognition). It is shown that it is possible to classify the signals from a given polymer sample into relatively few types and that there is a periodicity in a number of plots of acoustic power vs time. Differences between samples are evident, although it is not possible at this stage to state that they are statistically significant. The materials examined include, nylon-6,6, ‘Diakon’, polypropylene and various composites.  相似文献   
100.
The purpose of this study was to document alterations in endothelial and smooth muscle cell morphology of first- and second-order intestinal arterioles after 6 months of streptozotocin-induced diabetes. Both light and scanning electron microscopic techniques were used to quantitate the changes in the microvasculature. After rendering the first- and second-order intestinal arterioles passive and processing the vessels, it was determined that these microvessels were significantly dilated in the diabetic animals. Further examination revealed that in the diabetic animals, the cross-sectional area of the endothelial layer was increased in both 1A and 2A vessels, and the smooth muscle layer cross-sectional area was significantly increased in 1A vessels. Individual smooth muscle cells were significantly increased in width in the diabetic animals, but not in length. These data suggest that in this model of diabetes in rats, intestinal arteriolar hypertrophy was accompanied by significant remodeling of the arteriolar wall.  相似文献   
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