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161.
We attempted to determine health and economic outcomes from the perspective of an integrated health system of administering enoxaparin 30 mg twice/day versus heparin 5000 U twice/day for prophylaxis against venous thrombosis after major trauma. A decision-analytic model was developed from best literature evidence, institutional data, and expert opinion. We assumed that 40% of proximal deep vein thromboses (DVTs) and 5% of distal DVTs are diagnosed and confirmed with initial or repeat duplex scanning; 50% of undiagnosed proximal DVTs result in pulmonary embolism; 2% and 1% of undiagnosed proximal DVTs will lead to readmission for DVT and pulmonary embolism, respectively, and pulmonary embolism-related mortality rates range from 8-30%. Length of hospital stay data and 1996 institutional drug use and acquisition cost data were used to estimate the cost of enoxaparin and heparin therapy. Diagnosis and treatment costs for DVT and pulmonary embolism were derived from institutional charge data using cost:charge ratios. A second analysis of patients with lower extremity fractures was completed. One-way and multiway sensitivity analyses were performed. For 1000 mixed trauma patients receiving enoxaparin versus heparin, our model showed that 62.2 (95% CI -113 to -12) DVTs or pulmonary emboli would be avoided, resulting in 67.6 (8 to 130) life-years saved at a net cost increase of $104,764 (-$329,300 to $159,600). Enoxaparin versus heparin resulted in a cost of $1684 (-$3600 to $9800) for each DVT or pulmonary embolus avoided and a discounted cost/life-year saved of $2303 (-$8100 to $19,000). For 1000 patients with lower extremity fractures, enoxaparin versus heparin resulted in a cost of $751 (-$4200 to $3300) for each DVT or pulmonary embolus avoided and a discounted cost/life-year saved of $1017 (-$10,200 to $6300). Although enoxaparin increases overall health care costs, it is associated with a cost/additional life-year saved of only $2300, which is generally lower than the commonly used hurdle rate of $30,000/life-year saved. The cost-effectiveness ratio is more favorable in patients with lower extremity fractures than in the general mixed trauma population.  相似文献   
162.
C. Judson King 《Drying Technology》2013,31(5-7):1221-1240
ABSTRACT

Retention or loss of trace volatile compounds during spray drying can be vital for product quality. Examples of cases where loss or retentions of volatile substances are important include retention of balanced flavor and aroma in food products, removal of odiferous substances, and control of the release of volatile organic compounds to the atmosphere. Factors and mechanisms determining losses of these substances are reviewed. Losses can occur during atomization, from undisturbed drops and as a result of morphological development. On the basis of this insight, several avenues for controlling the retention of volatile substances are identified and analyzed. These include control of atomizer pressure or rotation speed, choice of spray angle, configuration of air input, lteration of the air temperature profile, feed concentration, the presence of an oil phase and/or suspended solids, foaming of the feed, feed composition, and steam blanketing of the atomizer.

The quality of a spray-dried product can be strongly affected by the presence or absence of volatile compounds that were present in the feed to the spray dryer. For example, spray-dried coffee and tea have suffered from a air and thereby avoid bubble formation, expansion and bursting for deaerated feeds (20). This approach produces a product with high bulk density. If that result is cceptable, then it should also be a way of precluding volatiles loss due to morphological development.  相似文献   
163.
Under in vitro conditions, muscle larvae of Trichinella spiralis secreted minute amounts of a cysteine proteinase into the outer environment from the stichosome. The proteinase hydrolyzed azocoll at pH 5.0 but not a number of synthetic N-blocked and N-unsubstituted proteinase substrates at this pH. The reducing compound dithioerythritol enhanced the enzyme activity, but the thiol-blocking reagent sodium-p-hydroxymercuribenzoate (0.1 mM) was without effect. Phenylmethylsulfonyl fluoride (PMSF) (2 mM) and leupeptin (100 mM) produced partial and complete inhibition, respectively, whereas soybean trypsin inhibitor, pepstatin A, and 1,10-phenanthroline were non-inhibitory. Calcium (1 mM) produced a slight decrease in the activity that was reversed by 1 mM EGTA. Although multiple proteinase activities were detected histochemically in the somatic muscles, stichosome, midgut, and genital primordium of the muscle larvae, none of these enzymes appeared to be the one secreted. Several histochemically demonstrable proteinases were also found in the cells of 48- to 72-h-old juveniles of the parasite. One was localized in the esophageal lumen and at or around the anterior esophagus of the larvae, where developing stichocytes are believed to occur. The proteinase hydrolyzed N-acetyl-L-methionine-L-naphthyl ester and was sensitive to the metal cation-complexing compound EGTA as well as to PMSF, an inhibitor of serine proteinases.  相似文献   
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165.
A longitudinally linked data set for Georgia was used to identify characteristics, including previous prenatal care use and complications at the first birth, associated with prenatal care use in the second pregnancy among 8,224 African-American women. More than 70% of the women who were < 25 years of age at their first birth (younger women) and almost 40% of women who were > or = 25 years at their first birth received inadequate care with at least one of their first two births. Women who received inadequate care in their first pregnancy were more likely to receive inadequate care in their second pregnancy than women who received adequate care in their first pregnancy. Younger women with a history of a stillbirth, neonatal death, or vacuum extraction were less likely to receive inadequate care in their subsequent pregnancy. Although this study was not able to evaluate the content of prenatal care, it suggested that many African-American women may not receive sufficient care to prevent adverse pregnancy outcomes. Women who receive inadequate care in their first pregnancy must be targeted for interventions that help them overcome economic, situational, or attitudinal barriers to receiving adequate care in their next pregnancy.  相似文献   
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OBJECTIVE: This study tested the hypothesis that gut stasis induced by parenteral morphine sulfate (MS) leads to enhanced bacterial translocation in rats on total parenteral nutrition (TPN). SUMMARY BACKGROUND DATA: TPN and MS are common adjuncts in the care of critically ill patients. TPN is known to provoke a variable degree of translocation. MS induces gut stasis with an accompanying bacterial overgrowth. The effect of these two treatments in combination on translocation is not known. METHODS: Rats were provided with central and subcutaneous lines for the continuous infusion of nutrients and drugs, respectively. Intestinal transit was assessed by the caudal movement of a fluorescent marker intubated into the proximal duodenum. Quantitative bacteriology was carried out from various segments of the gut and from ileocecal mesenteric lymph nodes (MLN), spleen, liver, and systemic blood obtained by cardia puncture on sacrifice at 96 hours. RESULTS: Transit was unchanged by TPN alone but prolonged when given in combination with MS. Bacterial overgrowth was also enhanced by MS and increased the bacterial translocation to MLN from 50% of animals with TPN, to 100% in those receiving both TPN and MS; the colony-forming units per MLN increased from 33 +/- 14 with TPN alone to 2079 +/- 811 (STD) with TPN plus MS. Furthermore, no bacteria were found at systemic sites with TPN alone, but in 93.3% of animals receiving TPN and MS. In a subgroup of rates provided with glutamine in TPN, the TPN plus MS effects on translocation were not reversed. CONCLUSIONS: These observations demonstrate the important role that morphine plays in promoting translocation, presumably by disrupting fasting motility and enhancing bacterial overgrowth.  相似文献   
170.
The purpose of this study was to examine the effect of carbogen gas (95% O2-5% CO2) on uptake and metabolism of 5-fluorouracil (5FU) in murine RIF-1 tumors and their growth in vivo. In addition, we have explored the mechanisms by which carbogen can transiently affect the physiology of RIF-1 tumors. After i.p. injection of 1 mmol/kg 5FU into C3H mice, the uptake and metabolism of the drug by s.c. RIF-1 tumors was followed for 2 h noninvasively using 19F-magnetic resonance spectroscopy (MRS). In all animals, irrespective of tumor size, carbogen caused a significant increase in the half-life (t(1/2)) of the elimination of 5FU by the tumor and a significant increase in growth inhibition. In 2-3-g tumors (group II), carbogen also caused increased 5FU uptake and metabolism to the cytotoxic 5-fluoronucleotides, whereas in 0.8-1.5-g tumors (group I), only the t(1/2) was slightly increased. These results suggested that tumor size was an important factor in the effect of carbogen on tumor physiology. Measurements of RIF-1 tumor vascular and necrotic volume showed no significant differences between group I and group II tumors. However, 1H-MR images of RIF-1 tumors showed that carbogen caused a transient decrease in signal intensity, which correlated positively (P = 0.02) with tumor size, suggesting that larger tumors responded to carbogen by transiently increasing O2 uptake from the blood. 19F-MRS was used to measure RIF-1 tumor retention of the fluorinated nitroimidazole SR-4554. These studies also showed a positive correlation (P = 0.001) with tumor size, implying greater hypoxia in larger tumors. We propose that carbogen may transiently open nonfunctional blood vessels in the tumor, allowing increased leakage of 5FU from the plasma into the extracellular space. 5FU transport is known to be pH dependent. Intra- and extracellular tumor pH was measured using 31P- and 19F-MRS, which showed that carbogen caused a significant decrease in the extracellular pH of 0.1 unit in group II tumors and a consequent increase in the negative pH gradient across the tumor plasma membrane, which can cause increased 5FU uptake. The pH gradient was unaffected in group I tumors. We conclude that carbogen breathing can increase tumor uptake of 5FU by two independent mechanisms involving changes in tumor blood flow and pH, which consequently cause increased formation of 5-fluoronucleotides and cytotoxicity. The effect seems more pronounced in hypoxic tumors, implying that carbogen would be a valuable aid in clinical chemotherapy.  相似文献   
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