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51.
BACKGROUND: In end-stage renal disease, average bone mineral density has been reported to be normal or only modestly reduced, more so in the cortical bone. The purpose of the present study was to explore the potential use of quantitative ultrasound, a method reflecting both quantitative and qualitative properties of bone, in assessing bone status in patients on maintenance haemodialysis. METHODS: We studied 71 patients (age 17-81 years, time on dialysis 0-18 years). The speed of sound waves (tSOS; m/s) propagating along the cortical bone has been determined at the tibial shaft. tSOS results were expressed as Z scores, i.e. units of standard deviations from age- and sex-matched normal mean values, and correlated with relevant clinical and biochemical variables. RESULTS: SOS Z score averaged -2. 0 (range -6.8 to 0.6; P<0.001) and was negative in 93% of the patients. Significant inverse correlations were found between SOS Z score and both time on dialysis (r=-0.52; P<0.0001) and serum PTH (r=-0.39; P=0.0002). Markedly reduced SOS Z score, below -2, was found in 80% of the patients whose PTH levels exceeded 34 pmol/l (five times the upper normal limit), compared with 43% of the patients whose PTH levels were below 34 pmol/l(P=0.04). Compared to patients without bone pain (n=51), subjects with bone pain (n=20) had somewhat lower SOS Z scores -2.5+/-2.0 versus -1.8+/-1.4; P=0. 08), but this could be accounted for by longer time on dialysis. CONCLUSIONS: tSOS is substantially reduced in the majority of haemodialysed patients and is related to time on dialysis and serum PTH level. The clinical value of this novel method needs further exploration. 相似文献
52.
KC Silverman C Cascales O Genilloud JM Sigmund SE Gartner GE Koch MM Gagliardi BK Heimbuch M Nallin-Omstead M Sanchez 《Canadian Metallurgical Quarterly》1995,43(4):610-616
Actinoplanic acids A and B are macrocyclic polycarboxylic acids that are potent reversible inhibitors of farnesyl-protein transferase. Actinoplanic acids A and B were isolated from Actinoplanes sp. MA 7066 while actinoplanic acid B was isolated from both MA 7066 and Streptomyces sp. MA 7099. Actinoplanic acids A and B are competitive with respect to farnesyl diphosphate and are selective inhibitors of farnesyl-protein transferase because they do not inhibit geranylgeranyl-protein transferase type 1 or squalene synthase. MA 7066 is believed to be a novel species of actinomycetes while MA 7099 is believed to be a novel strain of Streptomyces violaceusniger on the basis of morphological, biochemical and chemotaxonomic characteristics as well as its production of actinoplanic acids. 相似文献
53.
HO Ammar M Ghorab SA el-Nahhas SM Omar MM Ghorab 《Canadian Metallurgical Quarterly》1995,50(12):805-808
This study is a retrospective review of admissions, discharge records and blood culture results of neonates admitted to the Neonatal Intensive Care Unit of Korle Bu Teaching Hospital in Accra, from the first of January 1991 to the 31st of December 1992. During this two year period there were 443 positive blood cultures. Ninety percent of the blood cultures were from babies born in Korle Bu Teaching Hospital, thus making the incidence of neonatal bacteraemia 22.2 per 1000 live births. The overall mortality rate was 37.2%. Gram negative bacteria accounted for 70.9% and Gram positive bacteria for 29.1% of all neonatal bacteraemia. The most common isolates were Enterobacter species 29.6%; Streptococcus faecalis 14.4%; Staphylococcus aureus 10.8%; Acinetobacter species 9.5%; Klebsiella species 9% and Escherichia coli 8.8%. It is concluded that the incidence of neonatal bacterial sepsis is high in our hospital and is associated with a very high mortality rate. There is thus an urgent need to institute appropriate preventive and therapeutic measures. 相似文献
54.
Accidental hypothermia: incidence, risk factors and clinical course of patients admitted to hospital
JJ Bierens R Uitslager MM Swenne-van Ingen WA van Stiphout JT Knape 《Canadian Metallurgical Quarterly》1995,2(1):38-46
This study was initiated to identify the incidence, risk factors and outcome predictors of patients admitted to hospital in the Netherlands because of accidental hypothermia. Information about these patients was available for study through the National Health Care Data Bank. Between 1987 and 1990, 612 accidental hypothermic patients were admitted: 185 hypothermic patients also suffered from submersion (HYPSUBS), but this was not the case in the remaining 427 patients (HYPNOTSUBS). Patients in the HYPNOTSUBS group were older (average age 55.2 years versus 38.9 years; p < 0.001), remained longer in hospital (average 20.8 days versus 9.2 days; p < 0.001) and had a higher death rate than those in the HYPSUBS group (16.9% versus 5.9%; p < 0.001). In HYPNOTSUBS, increasing age correlated with increases in the length of hospital stay and death rate. This relationship was not found in HYPSUBS. Trauma was the major associated problem in both groups; these patients had the highest death rate (22.8% versus 16.7%; not significant). Death occurred within 2 days in 54% of HYPNOTSUBS non-survivors and 73% of HYPSUB non-survivors. HYPNOTSUBS admitted to university hospitals showed a lower death rate (5.9%) compared with HYPNOTSUBS admitted to non-university hospitals with less than 400 beds (13.4%) or more than 400 beds (21.7%). In contrast, the death rate in HYPSUB was higher in university hospitals (14.3%) than in non-university hospitals with less than 400 beds (5.2%) or more than 400 beds (3.6%). We observed that the incidence of accidental hypothermia is low at 1.1 per 100,000 inhabitants per year. We concluded that HYPNOTSUBS and HYPSUB are different groups of patients with respect to demographic data, risk factors and prognostic factors. Old age is an important unfavourable prognostic factor in HYPNOTSUB but not in HYPSUB. Hypothermia with trauma is an unfavourable combination in both groups. Almost half of the HYPNOTSUBS non-survivors died after more than 2 days. Because body temperature will have returned to normal by then, this must be the result of late complications. Most HYPSUB non-survivors died during the first 2 days, probably as a direct result of the submersion injury. 相似文献
55.
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57.
RS Miller DA Weatherford D Stein MM Crane M Stein 《Canadian Metallurgical Quarterly》1994,37(3):442-445
Using capillary videomicroscopy of the nail fold, the frequency of cold-induced vasospasm and capillary hemodynamic parameters were studied after application of cold in 50 patients with primary fibromyalgia, 50 patients with chronic low back pain, and 50 healthy controls. Cold-induced vasospasm was detected in 38% of the patients with fibromyalgia. In this group it was significantly more frequent than in the patients with chronic low back pain (20%, p < 0.05) and healthy subjects (8%, p < 0.001). In the fibromyalgia group, the magnitude of vasospasm as measured by the capillary blood flow deceleration after cold application correlated negatively with the pain intensity as measured by pain score (r = -0.3839, p < 0.01). No differences in clinical appearance were found between patients with and without cold-induced vasospasm in both the fibromyalgia and low back pain group. 相似文献
58.
The frying performance of low-linolenic acid soybean oil from genetically modified soybeans was examined. Partially hydrogenated
and unhydrogenated low-linolenic acid soybean oils were compared to two partially hydrogenated soybean frying oils. Frying
experiments utilizing shoestring potatoes and fish nuggets were conducted. Frying oil performance was evaluated by measuring
free fatty acid content, p-anisidine value, polar compound content, soap value, maximal foam height, polymeric material content, and Lovibond red color.
The hydrogenated low-linolenic soybean oil (Hyd-LoLn) consistently had greater (P<0.05) free fatty acid content and lower p-anisidine values and polymeric material content than did the other oils. Hyd-LoLn generally was not significantly different
from the traditional oils for polar content, maximal foam height, and Lovibond red color. The low-linolenic acid soybean oil
(LoLn) tended to have lower soap values and Lovibond red color scores than did the other oils. LoLn had consistently higher
(P<0.05) p-anisidine values and polymeric material content than did the other oils, and LoLn generally was not different (P<0.05) from the traditional oils for polar content, maximal foam height, and free fatty acid. 相似文献
59.
Hybrid magnetic nanostructures with high coercivity have immense application potential in various fields. Nickel (Ni) electrodeposited inside Cobalt (Co) nanotubes (a new system named Ni @ Co nanorods) were fabricated using a two-step potentiostatic electrodeposition method. Ni @ Co nanorods were crystalline, and they have an average diameter of 150 nm and length of ~15 μm. The X-ray diffraction studies revealed the existence of two separate phases corresponding to Ni and Co. Ni @ Co nanorods exhibited a very high longitudinal coercivity. The general mobility-assisted growth mechanism proposed for the growth of one-dimensional nanostructures inside nano porous alumina during potentiostatic electrodeposition is found to be valid in this case too. 相似文献
60.
Niina MM Saviranta Mikko J Anttonen Atte von Wright Reijo O Karjalainen 《Journal of the science of food and agriculture》2008,88(1):125-132
BACKGROUND: Red clover (Trifolium pratense L.), a widely used fodder, has recently received considerable interest as a valuable source of isoflavones for many health‐related applications. The aim of this study was to analyse the concentrations of four isoflavones, daidzein, genistein, formononetin and biochanin A, in extracts of leaves, stems, roots and different coloured flowers from red clover by high‐performance liquid chromatography and to determine the antifungal activities of the extracts. RESULTS: Among greenhouse‐grown samples the highest amounts of daidzein and genistein were found in petioles (0.11–0.28 and 0.30–0.54 mg g?1 respectively), while leaves were rich in formononetin and biochanin A (5.57–9.05 and 10.94–14.59 mg g?1 respectively). High formononetin concentrations were found in roots, but very little biochanin A. Among field‐grown samples the highest concentrations of daidzein and genistein were detected in stems collected in August (0.24 and 0.55 mg g?1 respectively), while the highest amounts of formononetin and biochanin A were found in young leaves collected in June (7.47 and 9.69 mg g?1 respectively). Most of the extracts inhibited the growth of Drechslera teres, while the root extract showed the strongest effect against Microdochium nivale. CONCLUSION: High levels of bioactive compounds found not only in inflorescences but also in roots, leaves and stems suggest that red clover may be an inexpensive and valuable resource for many applications. Copyright © 2007 Society of Chemical Industry 相似文献