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101.
BACKGROUND: Urea kinetic modeling (UKM) and creatinine (Cr) kinetic modeling (CKM) are used in the nutritional evaluation of end-stage renal disease (ESRD) patients. Both the UKM-derived normalized protein catabolic rate (nPCR) and the CKM-derived estimate of lean body mass (LBM) may also provide important information in critically ill acute renal failure (ARF) patients. Estimation of LBM may be particularly useful as previous data demonstrate that malnutrition adversely influences outcome in ARF patients. METHODS: Eleven critically ill ARF patients (age 52 +/- 21 years; mean +/- SD) treated with continuous venovenous hemofiltration (CVVH) were the study group. They were analyzed at steady state with a single-pool variable-volume model that determined the creatinine generation rate (GCr) by a methodology that we have previously described. RESULTS: The CVVH ultrafiltrate production rate was 913 +/- 49 ml/hr, yielding a blood Cr clearance of 15.2 +/- 0.9 ml/min and a steady state serum Cr of 3.4 +/- 1.7 mg/dl. Daily creatinine generation normalized to body wt (creatinine index: CI) was 6.3 +/- 0.8 and 10.6 +/- 3.0 mg/kg/day for females (N = 4) and males (N = 7), respectively (P < 0.05). Estimated mean LBM was 30.0 +/- 2.0 and 41.2 +/- 7.0 kg in females and males, respectively (P < 0.05), while the same parameter normalized to body wt was 0.50 +/- 0.05 and 0.52 +/- 0.10, respectively. These values are substantially lower than those previously reported for both normal and ESRD patients. Regression analysis demonstrated both GCr (r2 = 0.96; P < 0.001) and LBM (r2 = 0.96; P < 0.001) were significantly correlated with steady state serum Cr in a linear manner. However, no significant correlation (r2 = 0.06; P = 0.24) between nPCR and CI was observed. CONCLUSIONS: These data suggest critically ill ARF patients have severe somatic protein depletion. This malnourished state is likely due to deficits established prior to the development of ARF, such as those secondary to underlying chronic illnesses or prolonged hospitalization, and deficits related to acute hypercatabolism. Quantitative assessment of malnutrition in ARF patients with this CKM-based methodology may permit a better understanding of predisposing factors and, consequently, facilitate the development of interventions designed to prevent malnutrition in these patients. 相似文献
102.
BA Revich AA Bykov SM Liapunov AM Prikhozhan IF Ser?gina MB Sobolev 《Canadian Metallurgical Quarterly》1998,(12):25-32
Lead releases in Belovo town containing metallurgy enterprise had reached 120 tons/year earlier, but in recent years have decreased to 9 tons/year. Reduction of the production induced decrease of lead levels in the ambient air from 0.7-2.3 mg/m3 in 1994 to 0.001-0.24 mg/m3. Lead concentration in the soil ranges from 30 to 3000 mg/kg. Lead levels were measured in serum of 91 children, in hair of 67 ones and in teeth of 15 children. Serum lead levels in children aged 7-8 years varied from 0.5 to 39 mg/dl, with an average of 9.9 mg/dl (SD is 5.2 mg/dl), geometric mean is 8.5 mg/dl and error of geometric mean is 3.3. 46% of the children had serum lead levels exceeding the normal one (10 mg/dl). Average lead level in the hair equaled 4.5 mg/g (SD is 4.9 mg/g). The children living in towns with higher environmental lead levels demonstrated more frequent anxiety and changes in higher psychic functions. The major points influencing the serum lead level are proximity to highway, dietary load of goods grown near the residence, mother's smoking. Biokinetic model describing lead transfer into the blood helped to evaluate various modes of the enterprise functioning and efficiency of some environmental protection measures. The most efficient are measures aimed to lower dietary intake of lead, less efficiency is associated with measures reducing lead levels in air, dust and soil. 相似文献
103.
Effects of growth hormone, insulin-like growth factor-I, and cortisol on periparturient antibody response profiles of dairy cattle 总被引:2,自引:0,他引:2
The objectives of this study were to determine hormone and antibody response profiles from the prepartum period to peak lactation, and evaluate potential immunomodulatory effects of the classic endocrine hormones, growth hormone (GH), insulin-like growth factor-I (IGF-I) and cortisol. Specifically, 33 Holstein cows were immunized with ovalbumin (OVA) and Escherichia coli J5 at weeks -8 and -3 prior to parturition. At parturition (week 0), cows received an additional immunization of OVA. Blood was collected at weeks -8, -3, 0, 3 and 6 relative to parturition and various samples were used to determine plasma hormone concentration, serum immunoglobulin (Ig), and specific antibody response to OVA and E. coli. Colostrum and milk samples were also collected post-parturition to monitor local immunoglobulin and antibody responses. Results indicated that not all periparturient cows exhibited depressed immune response, and that antibody response to OVA could be used to partition cows into 3 groups recognizing animals with sustained measurable antibody response before and after parturition (Group 1), animals which responded poorly to immunization at parturition (Group 2), and animals which did not respond to immunizations at week -3 or parturition (Group 3). Cows with the highest antibody response to OVA (Group 1) also tended (P < or = 0.10) to have the highest response to E. coli J5 at parturition and had the lowest incidence of disease, particularly mastitis. Antibody response to OVA measured in milk tended to be higher in Group 1 cows, particularly at week 0 (P < or = 0.06) compared to cows of Group 3. IGF-I was higher (P < or = 0.05) in cows of Group 1 than Group 3 at peak lactation (week 6). 相似文献
104.
Impaired nasal breathing has been reported to cause changes in human head posture. The aim of this study was to assess whether there was any relationship between nasorespiratory function and variables of head posture in 58 young adults. The pressure flow technique was used to measure airflow rate and oral/nasal pressure and to calculate the smallest cross-sectional area of the nasal airway. A natural head position roentgenocephalogram was used to measure the craniovertical angulation (NSL/VER), craniocervical angulation (NSL/OPT), and cervical spine inclination (OPT/HOR). The results showed a trend toward enlarged craniocervical angulation and forward inclination of the cervical spine in subjects with a relatively large nasal cross-sectional area. Though the general opinion on the effects of reduced upper airway size on head posture is opposite, these results are an experimental confirmation of the theoretically expected mechanism that leads to increased head extension in obstructed subjects. 相似文献
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以酯基为连接基的非离子双子表面活性剂的合成 总被引:1,自引:0,他引:1
以蓖麻油酸(RA)、聚乙二醇(600)为原料,马来酸酐为连接基,合成了一种新型的非离子双子表面活性剂MARAPEG-15,考察了催化剂用量、物料摩尔配比、反应时间及温度对酸酐与蓖麻油酸聚乙二醇硼酸酯酯化的影响,并测定了产物的临界胶束浓度和表面张力。马来酸酐与蓖麻油酸聚乙二醇硼酸酯酯化较佳的工艺条件为:催化剂用量为总质量的3%,n(酸酐)∶n(蓖麻油酸聚乙二醇硼酸酯)为3.1∶2,反应温度为110℃,时间为4 h;硼酸酯键水解时间为1.5 h。产物的表面张力及其临界胶束浓度为γCMC=35.73 mN/m,CMC=1.96×10-5mol/L。 相似文献