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51.
Gaudichon C Mahé S Benamouzig R Luengo C Fouillet H Daré S Van Oycke M Ferrière F Rautureau J Tomé D 《The Journal of nutrition》1999,129(4):890-895
The aim of this study was to follow the fate of dietary nitrogen to assess the postprandial utilization of purified milk protein and to determine the acute influence of energy nutrients. For this purpose, a [15N]-labeling dietary protein approach was used. Twenty-five subjects swallowed an ileal tube and ingested [15 N]-milk protein alone or supplemented with either milk fat or sucrose. The absorption and postprandial deamination of dietary protein was monitored for 8 h. Sucrose delayed the absorption of protein longer than fat, but the ileal digestibility did not differ among groups (94.5-94.8%). Sucrose, but not fat, significantly reduced the postprandial transfer of [15N]-milk nitrogen to urea. Consequently, the net postprandial protein utilization (NPPU) of milk protein calculated 8 h after meal ingestion was 80% when ingested either alone or supplemented with fat and was significantly greater with sucrose (NPPU = 85%). This study shows that energy nutrients do not affect the nitrogen absorption but modify the metabolic utilization of dietary protein in the phase of nitrogen gain. Our method provides information concerning the deamination kinetics of dietary amino acids and further allows the detection of differences of dietary protein utilization in acute conditions. The diet composition should be carefully considered, and protein quality must be determined under optimal conditions of utilization. 相似文献
52.
53.
Lang T Ducimetière P Arveiler D Amouyel P Ferrières J Ruidavets JB Montaye M Haas B Bingham A 《International journal of epidemiology》1999,28(6):1050-1058
OBJECTIVES: To assess whether different definitions of acute coronary events yielded concordant results concerning trends and geographical disparities in coronary heart disease (CHD) mortality and morbidity in France. STUDY DESIGN: Data from three French CHD registries participating in the WHO MONICA Project during the period 1985-1992. SETTING: Three areas of about one million inhabitants each in the North, South and East of France. SUBJECTS: About 2,000 acute coronary events each year. MAIN OUTCOME MEASURES: Mortality, annual rate of fatal and non-fatal events, incidence of first and recurrent events, case-fatality rates. RESULTS: For incidence and mortality, the broader the broader the definition of the acute event, the higher the reported rates. The same tendency was not observed for case-fatality rates. Comparing between-registry rates for mortality, 28-day case-fatality and hospital case fatality yielded relatively concordant results whatever the definition of event. As a whole, the higher mortality rate in Lille and its intermediate rank in Strasbourg were related more to disparities in case-fatality rates, with only small variations in incidence rates, independently of the definition used. Comparing temporal trends in rates within and between regions, a consistent decrease in annual mortality rates and case-fatality rates was observed, whatever the definition. In contrast, the incidence of non-fatal probable myocardial infarction did not change during the period in any register. CONCLUSIONS: Although the absolute estimates of rates were variable with the definition of the event, major findings in relation to trends and geographical disparities were fairly consistent across the definitions: the North-South gradient in mortality observed in France was found to be much more pronounced for case fatality than for incidence. The proportion of milder acute myocardial infarction is currently increasing and this element should be taken into account when analysing CHD rates. 相似文献
54.
vgf is an inducible gene, highly sensitive to nerve growth factor (NGF) and remarkably upregulated in the "early-delayed" phase of response (within a few hours). It encodes a 617-amino acid polypeptide (VGF protein) bearing no significant homology with known sequences and restricted to certain peptide/amine-producing endocrine cells, and neurons (for example, adenohypophysial and adrenal medullary cells, or hypothalamic neuroendocrine neurons). VGF is stored and transported in secretory granules and processed to intermediate-small molecular weight products, which are preferentially released. Striking changes in both VGF mRNA and immunolocalization are found in physiological conditions (for example, estrous cycle) and in experimental models of stimulation affecting hypothalamic and other neurons. Functional roles of VGF are to be sought in secretory granule formation and regulation, and/or in the production of potentially bioactive peptides. 相似文献
55.
Rhombencephalosynapsis is an unusual disorder characterised by maldevelopment of the rhombencephalon, sometimes with supratentorial
midline anomalies. We report MRI findings in a 39-year-old woman, the oldest in the literature. MRI demonstrated hypoplasia
of the cerebellar vermis, with fusion of the cerebellar hemispheres and abnormally oriented folia. Supratentorial anomalies
were also seen.
Received: 26 April 1999 Accepted: 13 July 1999 相似文献
56.
高效液相色谱法测定绿茶和饮料中的咖啡因 总被引:5,自引:0,他引:5
采用反相高效液相色谱法,固定相为十八烷基硅烷键合硅胶,以乙腈-水(20:80)为流动相,检测波长274nm,测定绿茶和饮料中的咖啡因含量。结果线性范围为3.9~3900ng,r=O.9999;绿茶和2种饮料的平均加样回收率分别为100.2%、100.1%和99.8%。该方法准确、简便、快速,适合绿茶和可乐型饮料中咖啡因的测定。 相似文献
57.
BACKGROUND AND OBJECTIVE: Nd:YAG laser photothermal ablation has been accepted as a treatment modality for hemorrhoidal disease. There is little reported on its use in treating pilonidal disease. We hypothesized that laser would be an excellent tool for pilonidal cystectomy, facilitating improved outcome and patient satisfaction. STUDY DESIGN/MATERIALS AND METHODS: A 5-year retrospective study was performed comparing Nd:YAG laser to the standard surgical technique. A telephone questionnaire addressing the length of time the cyst was debilitating both preoperatively and postoperatively as well as length of convalescent time before return to work was administered. Pain was assessed by using an analog pain scale. RESULTS: Operative time for the traditional pilonidal cystectomy was 20 minutes longer than Nd:YAG laser cystectomy. Postoperative hospital stay was similar. Laser patients returned to work an average of 2.4 days earlier, and their postoperative pain was less than those treated traditionally. CONCLUSION: In an era when the medical consumer makes decisions based on the efficacy of treatment by using criteria such as pain, length of hospitalization, and speed of return to work, Nd:YAG lasers have emerged as a surgical tool that can fulfill these criteria for certain procedures. Patient postoperative satisfaction after laser excision was greater when compared with those who had traditional excisions. Postoperative pain was less, as was the pain experienced during the first week of recovery. Cost for both was comparable. 相似文献
58.
Abstract: Haemoptysis in otherwise healthy children is an uncommon event. Two cases of massive haemoptysis, subsequently requiring lobectomy, are discussed. In each case, foreign vegetable matter was identified despite previously normal bronchoscopy and minimal changes on chest radiograph. 相似文献
59.
OBJECTIVE: Because survival from admission to discharge does not provide parents and physicians information about future life expectancy in the premature neonate, we characterized the actuarial survival, defined as the future life expectancy from a given postnatal age, in a large inborn population of premature infants < 30 weeks' gestation. STUDY DESIGN: We determined daily actuarial survival of 1925 inborn infants (23 to 29 weeks' gestation) admitted to the Baylor Affiliated Nurseries from July 1986 through December 1994, stratified by 100-g birth weight and by 1-week gestational-age intervals. RESULTS: In the 501- to 600-g birth weight stratum, actuarial survival improved from 31% at birth, to 61% on day of life 7, and then to 75% on day of life 28; in the 901- to 1000-g birth weight stratum, actuarial survival improved from 88%, to 94%, and then to 98% throughout the same times, respectively. Similar trends were obtained when data were stratified by gestational age. CONCLUSIONS: Survival in the smallest infants improves dramatically during the first few days of life, but there is a significant risk for late death in the smallest of these infants. 相似文献
60.
外源核苷酸对免疫抑制小鼠胸腺细胞DNA损伤的影响 总被引:5,自引:0,他引:5
目的:检测外源核苷酸对经环磷酰胺诱导的免疫抑制小鼠胸腺细胞DNA损伤的影响。方法:采用18~20 g昆明种小鼠30只,雌雄各半,随机分成阴性对照组(NEC)、阳性对照组(POC)和核苷酸组(NTG),每组10只。NEC组和POC组小鼠均饲喂半纯合无核苷酸的基础日粮,NTG组则在基础日粮中添加0.25%的核苷酸,实验期为21 d。在实验结束前18 h POC组和NTG组小鼠按照150mg/kg bw的剂量腹腔注射环磷酰胺,NEC组注射生理盐水,实验结束时测定脾脏和胸腺脏器指数,并取胸腺细胞,做单细胞凝胶电泳,观察细胞DNA损伤情况。结果:在基础日粮中添加核苷酸对小鼠免疫器官重量没有显著影响(P>0.05),但能极显著降低受损胸腺细胞百分率(P<0.01)和受损细胞DNA尾长(P<0.01)。结论:外源核苷酸能显著降低免疫抑制小鼠受损胸腺细胞百分率和损伤程度。 相似文献