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991.
992.
Relationships between 2 instrumental and 2 sensory methods for cookie color assessment were determined. For sensory tests, panelists (n = 8 to 10) compared color of cookies (3 formulations × 2 cookie types) to equidistant physical color references in a light booth and to digital color references in a sensory workstation using unstructured line scales. For instrumental methods, the CIELAB color model and hue angle were determined with a spectrophotometer and with graphics software using digital camera images. Analysis of variance (ANOVA) and post‐hoc comparisons verified differences (P < 0.05) among formulations within type by all methods. Except for b* values of chocolate chip cookies, the potential of all color assessment methods were validated by strong linear relationships (r > 0.94; P < 0.001). 相似文献
993.
OBJECTIVE: To determine how often electrocardiography, as an addition to history taking and physical examination, leads to changes in non-emergency patient management in general practice. DESIGN: Prospective observational study. SETTING: 18 general practices in Amersfoort and its surroundings, the Netherlands. METHOD: From the end of September, 1996 until the beginning of February 1997, the general practitioners (GPs) filled out two questionnaires each time an ECG was recorded, one before and one after the recording. The patient management planned by the GP before and after the availability of the ECG results was then compared. RESULTS: A total of 119 sets of questionnaires was obtained from 119 patients. In 47 patients (40%; 95% confidence interval: 31-48) the GP's management changed after recording and interpretation of the electrocardiogram. In particular, the decision whether or not to refer patients to a cardiologist was frequently changed (26 patients, 22%). The GPs management changed more often in patients in whom palpitations and dyspnoea had been the reason for taking an ECG. CONCLUSION: The use of electrocardiography in general practice in non-emergency situations would seem a valuable instrument in addition to history taking and physical examination. 相似文献
994.
PJ Savage SL Pressel JD Curb EB Schron WB Applegate HR Black J Cohen BR Davis P Frost W Smith N Gonzalez GP Guthrie A Oberman G Rutan JL Probstfield J Stamler 《Canadian Metallurgical Quarterly》1998,158(7):741-751
BACKGROUND: Previous studies often of short duration have raised concerns that antihypertensive therapy with diuretics and beta-blockers adversely alters levels of other cardiovascular disease risk factors. METHODS: The Systolic Hypertension in the Elderly Program was a community-based, multicenter, randomized, double-blind, placebo-controlled clinical trial of treatment of isolated systolic hypertension in men and women aged 60 years and older. This retrospective analysis evaluated development of diabetes mellitus in all 4736 participants in the Systolic Hypertension in the Elderly Program, including changes in serum chemistry test results in a subgroup for 3 years. Patients were randomized to receive placebo or treatment with active drugs, with the dose increased in stepwise fashion if blood pressure control goals were not attained: step 1, 12.5 mg of chlorthalidone or 25.0 mg of chlorthalidone; and step 2, the addition of 25 mg of atenolol or 50 mg of atenolol or reserpine or matching placebo. RESULTS: After 3 years, the active treatment group had a 13/4 mm Hg greater reduction in systolic and diastolic blood pressure than the placebo group (both groups, P<.001). New cases of diabetes were reported by 8.6% of the participants in the active treatment group and 7.5% of the participants in the placebo group (P=.25). Small effects of active treatment compared with placebo were observed with fasting levels of glucose (+0.20 mmol/L [+3.6 mg/dL]; P<.01), total cholesterol (+0.09 mmol/L [+3.5 mg/dL]; P<.01), high-density lipoprotein cholesterol (-0.02 mmol/L [-0.77 mg/dL]; P<.01) and creatinine (+2.8 micromol/L [+0.03 mg/dL]; P<.001). Larger effects were seen with fasting levels of triglycerides (+0.9 mmol/L [+17 mg/dL]; P<.001), uric acid (+35 micromol/L [+.06 mg/dL]; P<.001), and potassium (-0.3 mmol/L; P<.001). No evidence was found for a subgroup at higher risk of risk factor changes with active treatment. CONCLUSIONS: Antihypertensive therapy with low-dose chlorthalidone (supplemented if necessary) for isolated systolic hypertension lowers blood pressure and its cardiovascular disease complications and has relatively mild effects on other cardiovascular disease risk factor levels. 相似文献
995.
KJ Conrad MD Matters P Hanrahan DJ Luchins C Savage B Daugherty 《Canadian Metallurgical Quarterly》1998,49(9):1223-1225
This study compared the characteristics of 56 clients with severe mental illness in a community mental health agency's representative payeeship program with those of 54 clients who did not participate in the program. Based on data from a two-year period, participants in the representative payee program were characterized by disability or financial distress, indicated by a diagnosis of schizophrenia, homelessness, lack of rent money, and lack of financial skills; long-term dependence on income from Social Security and services provided by the mental health system, evidenced by receipt of Supplemental Security Income and frequent hospitalizations; and lack of financial independence, as reflected by inability to earn income from employment and lack of financial support from family. 相似文献
996.
Human beta-glucuronidase is a member of the Family 2 glycosylhydrolases that cleaves beta-D-glucuronic acid residues from the nonreducing termini of glycosaminoglycans. The enzyme is shown to catalyze glycoside bond hydrolysis with net retention of anomeric configuration, presumably via a mechanism involving a covalent glucuronyl-enzyme intermediate. Incubation of human beta-glucuronidase with 2-deoxy-2-fluoro-beta-D-glucuronyl fluoride resulted in time-dependent inactivation of the enzyme through the accumulation of a covalent 2-deoxy-2-fluoro-alpha-D-glucuronyl-enzyme, as observed by electrospray mass spectrometry. Regeneration of the free enzyme by hydrolysis or transglycosylation and removal of excess inactivator demonstrated that the covalent intermediate was kinetically competent. Peptic digestion of the 2-deoxy-2-fluoro-alpha-D-glucuronyl-enzyme intermediate and subsequent analysis by liquid chromatography coupled with electrospray ionization triple quadrupole mass spectrometry indicated the presence of a 2-deoxy-2-fluoro-alpha-D-glucuronyl peptide. Sequence determination of the labeled peptide by tandem mass spectrometry in the daughter ion scan mode permitted the identification of Glu-540 as the catalytic nucleophile within the sequence SEYGAET. 相似文献
997.
HC Lichtenbeld AF Barendsz-Janson H van Essen H Struijker Boudier AW Griffioen HF Hillen 《Canadian Metallurgical Quarterly》1998,77(3):455-459
Tumors need to acquire an angiogenic phenotype for outgrowth and metastasis formation. Limited information on the angiogenic potential of specific tissues, especially human breast tissues is available. Here we describe an in vivo model, using the dorsal skin fold chamber in immunodeficient nude mice, where various tissues of human breast origin were xenografted and evaluated for their angiogenesis-inducing potential. We found that angiogenesis was abundantly induced by all breast carcinoma tissue samples. Similar angiogenesis was induced by tissue samples from breasts with hyperplasia and apocrine metaplasia. Histologically normal tissues adjacent to the tumor induced angiogenesis in 66% of the cases. Angiogenesis was not induced by control tissues from normal healthy breasts, obtained after cosmetic breast reduction. Angiogenesis induction parallelled VEGF production by the tumor cells. The tissue induced neovascularization, found both around and in the human tissue, was functional since a tail vein injection of albumin-FITC revealed positive tumor microcirculation within 5 min, while the tumor tissue still consisted of vital human epithelial cells after 14 days. 相似文献
998.
Time-lapse microscopy reveals unique roles for kinesins during anaphase in budding yeast 总被引:1,自引:0,他引:1
The mitotic spindle is a complex and dynamic structure. Genetic analysis in budding yeast has identified two sets of kinesin-like motors, Cin8p and Kip1p, and Kar3p and Kip3p, that have overlapping functions in mitosis. We have studied the role of three of these motors by video microscopy of motor mutants whose microtubules and centromeres were marked with green fluorescent protein. Despite their functional overlap, each motor mutant has a specific defect in mitosis: cin8Delta mutants lack the rapid phase of anaphase B, kip1Delta mutants show defects in the slow phase of anaphase B, and kip3Delta mutants prolong the duration of anaphase to the point at which the spindle becomes longer than the cell. The kip3Delta and kip1Delta mutants affect the duration of anaphase, but cin8Delta does not. 相似文献
999.
JH van de Bovenkamp CM Hau GJ Strous HA Büller J Dekker AW Einerhand 《Canadian Metallurgical Quarterly》1998,245(3):853-859
The central limitation hypothesis postulates that energy budgets are limited by the capacity for energy assimilation. Contradictory evidence from in vitro studies of nutrient uptake capacity of intestinal tissues indicates a margin, however, that could allow a higher rate of energy acquisition than actually measured. As a more direct test, I measured nutrient uptake capacity in vivo. This is possible in animals such as the neotropical nectar-feeding bats (Glossophaginae: Phyllostomidae) that have both rapid gut transit times and high daily metabolic needs. Here, during the steady-state period of feeding, the rate of food intake is equal to the rate of food processing and food egestion. Therefore, the rate of food absorption can be determined directly from the rate of food ingestion. Maximal feeding rates were elicited by limiting the time period available for feeding during the 24-hr day through manipulation of the light/dark (LD) cycle. During 4-hr nights (LD 20:4), sugar intake averaged 488 J/g/hr and was 73% higher than during 12-hr nights (LD12:12). A 16.4-g bat would assimilate 96 kJ/day if feeding at this maximal rate during a regular 12-hr foraging period. This would be sufficient for maintaining a positive energy balance even during extreme physical activity under the natural conditions of its tropical environment. Nutrient assimilation capacity could thus not be identified as the single central factor setting the metabolic ceiling. 相似文献
1000.
L Mellemkjoer G Gridley H M?ller AW Hsing MS Linet LA Brinton JH Olsen 《Canadian Metallurgical Quarterly》1997,159(32):4850-4853
The cancer pattern was investigated among 5072 patients with a discharge diagnosis of pernicious anaemia during 1977-1989, using data from the Danish Hospital Discharge, Central Population and Cancer registries. During 1-15 years of follow-up we found, in line with earlier reports, two to three-fold increases in the risk of cancer of the stomach, buccal cavity and pharynx, which were unchanged when the analysis was stratified according to sex and duration of follow-up. A previously reported positive association with haematological cancers could only be found for short term follow-up to indicate that no real association exists. Our cohort of patients with pernicious anaemia experienced significantly reduced risks of cervix and non-melanoma skin cancer. 相似文献