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1.
A series of long-chain quaternary ammonium halogen esters (UKK-chemicals), quaternary dimethyl tallow epoxypropyl ammonium halogens (EPK1), quaternary ditallow methyl epoxypropyl ammonium halogens (EPK2), and EPK2 oligomers (EPK2P) were synthesized. At acidic, neutral, or slightly basic conditions, EPK1-, EPK2-, EPK2P-, and UKK-chemicals operate as cationic chemicals. They can be used, for example, as stock sizings, surface sizings, or fixatives. Stock sizing, surface sizing, and fixative experiments indicate that EPK1-, EPK2-, EPK2P-, and UKK-chemicals function at least as well as or better than the corresponding synthetic chemicals used in papermaking.  相似文献   
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The aim of this study was to examine the response of the autonomic nervous system in younger (mean age 31 yrs, n=14) and older (mean age 54 yrs, n=14) healthy female teachers during work periods of perceived high and low stress. In the younger participants, heart rate, cortisol excretion rate and psychosomatic symptoms were significantly higher during the high work stress period. The older participants experienced no decrease in their heart rate and cortisol excretion during the low stress period and they exhibited no significant decrease in blood pressure after the work in the evening during both periods. It may be concluded that the recovery from the stress in the older teachers was insufficient particularly in view of their elevated diastolic blood pressure during the low work stress period. Ergonomic and individually tailored measures in terms of work time control, specific relaxation techniques, and a part-time retirement may improve the stress management of older teachers.  相似文献   
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In 100% inspection, measurement errors are unavoidable. Due to these errors, acceptable products are sometimes rejected (overkill) and defective products are accepted (escape). Overkill increases production costs, while escape is a source of customer dissatisfaction. This study presents a model for calculating overkill and escape rates using process and measurement system performance data. A practical example of applying the model is also presented to calculate gage reproducibility and repeatability requirements for different production settings. Industrial managers and quality engineers can utilize the results of this study to calculate escape and overkill rates of their production systems, and to assess and improve their processes.  相似文献   
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An initial improvement in glycemic control is often followed by gradual deterioration of glycemia during insulin treatment of patients with noninsulin-dependent diabetes mellitus (NIDDM). We examined the causes of such worsening in a 12-month follow-up analysis of 100 insulin-treated NIDDM patients in the Finnish Multicenter Insulin Therapy Study who were treated with either combination therapy with insulin or insulin alone. In the entire study group, glycemic control averaged 9.7 +/- 0.2% at 0 months and 8.0 +/- 0.1%, 8.0 +/- 0.1%, 8.2 +/- 0.1%, and 8.5 +/- 0.2% at 3, 6, 9, and 12 months (P < 0.001 for each time point vs. 0 months). Glycemic control at 12 months was significantly worse than that at 3 (P < 0.001), 6 (P < 0.001), and 9 months (P < 0.02). Baseline body mass index was the most significant predictor of deterioration in glycemic control. During 1 yr, hemoglobin A1c decreased almost 3-fold more (by 1.7 +/- 0.2%; P < 0.001 vs. 0 months) in patients whose baseline weight was below the mean baseline body mass index of 28.1 kg/m2 (nonobese patients) than in those whose weight exceeded 28.1 kg/m2 (obese patients; 0.5 +/- 0.2%; P = NS vs. 0 months; P < 0.01 vs. obese patients). Glycemic control improved similarly over 1 yr in the nonobese subjects and deteriorated similarly in the obese patients regardless of their treatment regimen. Insulin doses, per body weight, were similar in the nonobese and obese patients. The nonobese patients consistently gained less weight during 12 months of combination therapy with insulin (3.5 +/- 0.6 kg at 12 months) than during insulin therapy alone (5.1 +/- 0.6 kg; P < 0.05). The treatment regimen did not influence weight gain in the obese group, who gained 4.4 +/- 1.0 kg during combination therapy with insulin and 4.5 +/- 1.1 kg during insulin therapy alone. We reached the following conclusions: 1) after an initial good response, glycemic control deteriorates more in obese than in nonobese patients with NIDDM; 2) in obese patients, weight gain per se cannot explain the poor glycemic response to combination or insulin therapy, but it may induce a disproportionately large increase in insulin requirements because of greater insulin resistance in the obese than in the nonobese; 3) in nonobese patients, glycemic control improves equally during 1 yr with combination therapy with insulin and insulin alone, but combination therapy with insulin is associated with less weight gain than treatment with insulin alone; 4) weight gain appears harmful, as it is associated with increases in blood pressure and low density lipoprotein cholesterol.  相似文献   
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The synthesis and degradation of type I and type III interstitial collagens releases several antigenic metabolites, whose measurement allows the metabolism of connective tissue to be evaluated under a variety of different conditions. In this study we investigated the influence of benign and malignant ovarian neoplasms on the metabolism of these collagens. The study population comprised patients with benign (n = 53), borderline (n = 6) or malignant (n = 36) ovarian neoplasms. We quantified the serum, cyst fluid and peritoneal/ascitic fluid concentrations of the amino-terminal propeptide of type I (PINP) and III (PIIINP) procollagens, indicators of the synthesis of type I and III collagen, respectively and the cross-linked carboxy-terminal telopeptide of type I collagen (ICTP), an indicator of type I collagen degradation. Macrophage colony-stimulating factor 1 (CSF-1) concentration was also assayed as its serum level is increased in ovarian cancer and CSF-1 may be involved in the regulation of collagen metabolism. The concentration of each antigen was significantly higher in patients with malignant tumour than with benign neoplasm in each comparison, except for ICTP in peritoneal fluid and for CSF-1 in cyst fluid. The high ascitic fluid concentration of PINP, PIIINP or CSF-1 correlated with malignancy, and the low cyst fluid concentration of any of the four markers was indicative of benign tumour. Levels of CSF-1 did not correlate with the levels of any of the markers of collagen turnover. The concentration of PINP in ascites was about 50 times higher and in cyst fluid about eight times higher than that in the serum from patients with malignant tumour, whereas the respective ratios for ICTP were only 2.5 and 1.3. In such patients, the ratio of ascitic fluid to serum concentration was also about 80-fold higher for PIIINP and about 20-fold higher for PINP than for ICTP. The different distributions of PIIINP, PINP and ICTP suggests dominance of synthetic processes or retarded elimination of PIIINP and PINP in ovarian cancer. In advanced malignancies, the accumulation of PINP and PIIINP in abdominal space, possibly due to increased synthesis and/or failed resorption, may promote ascites formation. This study shows that both accelerated synthesis and breakdown of fibrillar collagens are characteristic of ovarian malignancy, and suggests that measurements of cyst fluid or ascitic fluid concentrations of collagen metabolites or CSF-1 could be used in the differential diagnosis of benign and malignant ovarian neoplasms.  相似文献   
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Methods for management of diabetic pregnancy in the outpatient setting require strict glucose control. To assess the effect of diet and injection of short and intermediate acting insulin on glucose, diabetic patients tested their urine daily for glucose and had biweekly serum glucose tests. A brief metabolic ward study in 9 diabetic patients during the third trimester yielded hourly glucose determinations. These results defined the range of serum glucose over a 24-hour period. Glucose data on 6 normal third trimester women also came from hourly glucose values. Glucose results of normal and diabetic subjects were similar. A 16th subject with diabetic eye, renal, and foot complications is included as a case report to illustrate management technics. Infants of the diabetic women had no perinatal mortality, morbidity, or macrosomia and thus differ from an earlier study where glucose was not strictly controlled. The data suggest hospitalization can be short and low perinatal morbidity and mortality are possible with this outpatient method of management of the pregnant diabetic patient.  相似文献   
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During recent decades the amounts of nutrients discharged to Finnish surface waters have markedly decreased. This has been achieved by considerable investments in water protection, which were made mainly to improve municipal and industrial wastewater purification. We investigated whether these water protection measures have decreased phosphorus and nitrogen concentrations in Finnish rivers and lakes. In addition, possible trends in chlorophyll a concentrations in lakes were studied. The data consisted of a total of over 68 000 monitoring results of 22 rivers and 173 lakes (or sub-basins of lakes) with different types of catchment areas. The study period covered the years 1975–2000 and the non-parametric Kendall Tau b and Seasonal Kendall tests were applied for detecting trends. Decreasing nutrient concentration trends were typical in many lakes and rivers earlier polluted by municipal and industrial wastewaters. Increasing nutrient concentration trends were common in smaller rivers and lakes receiving diffuse loading from agriculture. The results show that the investments directed towards wastewater purification have effectively improved the quality of Finnish inland waters. However, no clear effects of decreasing non-point loading were found. Thus, more effective measures should be directed towards decreasing non-point source loading.  相似文献   
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The first microchip version of sonic spray ionization (SSI) as an atmospheric pressure ionization source for mass spectrometry (MS) is presented. The microchip used for SSI has recently been developed in our laboratory, and it has been used before as an atmospheric pressure chemical ionization (APCI) and atmospheric pressure photoionization (APPI) source. Now the ionization is achieved simply by applying high (sonic) speed nebulizer gas, without heat, corona discharge, or high voltage. The microchip SSI was applied to the analysis of tetra-N-butylammonium, verapamil, testosterone, angiotensin I, and ibuprofen. The limits of detection were in the range of 15 nM to 4 microM. The technique was found to be highly dependent on the position of the chip toward the mass spectrometer inlet, and on the gas and the sample solution flow rates. The microchip SSI provided dynamic linearity following a pattern similar to that used with electrospray, good quantitative repeatability (RSD=16%), and long-term signal stability.  相似文献   
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