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81.
三尖杉树皮粗提取物中的一个新生物碱—高三尖杉酯碱酰胺(homoharringtonamide)的结构,经质谱—质谱分析,初步建议为16。类似的酰胺类生物碱,例如三尖杉碱酰胺(cephalotaxamide,6)、11-羟基三尖杉碱酰胺(11-hydroxycephalotaxamide,9)、三尖杉酯碱酰胺(harfingtonamide,14)或异三尖杉酯碱酰胺(isoharringtonamide,15)也可能存在,后三者(9,14,15)尚未见报道。 相似文献
82.
83.
Blood loss and replacement in total hip arthroplasty: a multicenter study. The Preoperative Autologous Blood Donation Study Group 总被引:1,自引:0,他引:1
To determine blood loss, the number of transfusions, and the hemoglobin levels achieved in patients via transfusion in the course of total hip arthroplasty, 324 patient records from 1987 through 1989 were reviewed at three university and three community hospitals. Calculated blood loss was 3.2 +/- 1.3 units in primary procedures and 4.0 +/- 2.1 units in revision procedures (mean +/- SD). Of 777 red cell units transfused, 455 (59%) were autologous units. Transfused patients received 2.0 +/- 1.8 units for primary procedures and 2.9 +/- 2.3 units for revision procedures (mean +/- SD). The maximum number of units given to 95 percent of the transfused patients was 4 for primary procedures and 6 for revision procedures. The mean postoperative hemoglobin level after all transfusions was 103 to 110 g per L, regardless of patient age group of physical status, autologous donor status, or hospital. No difference in length of hospital stay was observed for patients less than 65 years old with hemoglobin concentrations of 80 to 139 g per L at discharge. 相似文献
84.
Philip C. Calder PhD Dan L. Waitzberg MD PhD Stanislaw Klek MD PhD Robert G. Martindale MD PhD 《JPEN. Journal of parenteral and enteral nutrition》2020,44(Z1):S21-S27
Lipid emulsions are an integral part of parenteral nutrition, and traditionally have been regarded as an energy-dense source of calories and essential fatty acids. For many years, lipids used in parenteral nutrition have been based on vegetable oils (eg, soybean-oil emulsions). However, soybean-oil emulsions may not have an optimal fatty-acid composition under some circumstances when used as the only lipid source, as soybean oil is particularly abundant in the ω-6 polyunsaturated fatty acid (PUFA), linoleic acid. Hence, a progressive series of more complex lipid emulsions have been introduced, typically combining soybean oil with 1 or more alternative oils, such as medium-chain triglycerides (MCTs) and/or olive oil and/or fish oil. The wide range of lipid emulsions now available for parenteral nutrition offers opportunities to alter the supply of different fatty acids, which potentially modifies functional properties, with effects on inflammatory processes, immune response, and hepatic metabolism. Fish oil has become an important component of modern, composite lipid emulsions, in part owing to a growing evidence base concerning its biological effects in a variety of preclinical models. These biological activities of fish oil are mainly attributed to its ω-3 PUFA content, particularly docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). DHA and EPA have known mechanisms of action, anti-inflammatory, immunomodulatory, and antioxidative properties. Specialized proresolving mediators, such as resolvins, protectins, and maresins, are synthesized directly from DHA and EPA, are key for the resolution of inflammation, and improve outcomes in many cell- and animal-based models and, recently, in some clinical settings. 相似文献
85.
PJ Fielder SE Gargosky M Vaccarello K Wilson P Cohen F Diamond J Guevara-Aguirre AL Rosenbloom RG Rosenfeld 《Acta paediatrica (Oslo, Norway : 1992)》1993,82(S389):40-43
Six adult patients with growth hormone receptor deficiency (GHRD) (2 men, 4 women) with an identical defect in the growth hormone receptor (GHR) gene, were treated with recombinant human insulin-like growth factor I (IGF-I), 40 μgikg S.C. twice daily, for 7 days. Serum concentrations of IGF peptide and IGF binding protein-3 (IGFBP-3) were measured by specific radioimmunoassays; serum IGFBPs were also measured by Western ligand blotting. The size distribution of both IGF-I and IGF-II was measured in serum following size-exclusion fast-performance liquid chromatography. IGF-I treatment resulted in a normalization of serum IGF-I levels on days 1–7 of treatment and a decrease in serum IGF-II levels. The fall in IGF-II levels and the simultaneous rise in IGF-I levels, however, resulted in an unchanged total serum IGF level. The low IGFBP-3 values did not significantly change during treatment, whereas there was a slight increase in IGFBP-2 levels. Preliminary analysis of size-fractionated sera suggested an increase in IGF-I levels in the 40 and 150 kDa regions at the expense of IGF-II levels. The results suggest that despite the failure of IGF-I treatment to increase IGFBPs significantly, serum IGFBP concentrations were sufficient to maintain normal levels of IGF-I. 0 Laron syndrome, growth hormone receptor deficiency, insulin-like growth factors, insulin-like growth factor binding protein 相似文献
86.
J. Martindale PhD BA Grad Dip Phys J. Smith PhD D. Grennan MD PhD L. Goodacre PhD J.A. Goodacre MD PhD 《Musculoskeletal care》2010,8(1):10-17
Background: People with ankylosing spondylitis (AS) typically experience episodic exacerbations, but the extent to which they subsequently experience a sustained reduction in disease markers below recognized thresholds for active disease is unclear. Objective: To investigate changes in, and associations between, disease markers over 18 months in people with active AS. Methods: Within a cohort of 89 participants with AS, Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) scores of 4 or higher were used to identify those with active disease. Standard assessment tools were used to monitor participants prospectively at four consecutive six‐monthly intervals. Participants received standard treatments but none received anti‐tumor necrosis factor‐alpha (TNFα) medication during the study. Results: The median age of the cohort was 50 years (inter‐quartile range [IQR] 38.5–55.5), the median age of disease onset was 25 years (IQR 18–33) and the median disease duration was 18 years (IQR 13–27). Forty‐seven (53%) participants had a BASDAI score of 4 or higher on the first assessment, of whom 45 (51%) scored 4 or higher on all subsequent assessments. Furthermore, 38 (43%) and 16 (18%) participants scored BASDAI 5 or 6, respectively, or higher, throughout. BASDAI scores correlated strongly with Bath Ankylosing Spondylitis Functional Index (BASFI) scores. Compared with 19 (21%) participants whose BASDAI scores were consistently below 4 throughout, participants with persistently high BASDAI scores showed higher scores for anxiety and depression, and some evidence of functional deterioration during the study period. Conclusions: In this cohort, disease markers in most people with active AS were sustained above the standard threshold for active disease. This has important implications for planning care pathways and for optimal utilization of anti‐TNFα treatment. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
87.
Mid-trimester loss--appraisal of a screening protocol 总被引:1,自引:0,他引:1
The main causes for mid-trimester loss are known. There is likely to be
overlap with those of first trimester loss, but the proportions may be
different. We wished to perform an aetiological survey in a large
population of patients with a history of recurrent miscarriage, for
possible explanations for their second trimester miscarriages. Database
analysis of 636 patients attending a UK University Teaching Hospital
dedicated miscarriage clinic between 1991 and 1996 revealed a 25%
prevalence (n = 158) for second trimester miscarriage. Results from an
investigative screening protocol were positive in 50% of cases: 33% (n =
52) tested positive for antiphospholipid syndrome (APS); 8% (n = 13)
fulfilled strict criteria for cervical incompetence; there was a 4%
prevalence of uterine anomaly; 3% for infection (n = 5) and 2% of patients
(n = 3) proved to be hypothyroid. Importantly, dual pathology was found in
5% of patients with a history of second trimester miscarriage. As
idiopathic mid-trimester loss is a diagnosis by exclusion, a high index of
suspicion is required, as are modern diagnostic techniques.
相似文献
88.
RESILIENCE AND VULNERABILITY IN LATER LIFE 总被引:1,自引:0,他引:1
Brian Martindale 《British Journal of Psychotherapy》2007,23(2):205-216
abstract The paper focuses on some psychological factors specific to the psycho-developmental tasks involved in ageing that may lead to a considerable loss of resilience and psychological breakdown for the first time since becoming adult. Issues connected with the potential increase of dependency, especially physical dependency are often central. The paper gives an account of reasons why this may be more threatening to some than others including the reawakening of childhood failures of dependency and also identifications with disturbing dependency experiences of late life of one's parents. 相似文献
89.
90.
Breast MR imaging with loop-gap resonators 总被引:1,自引:0,他引:1
Breast images obtained at 1.5 T using a loop-gap resonator pair as both the excitation and detection device are presented. The efficiency of this approach is high, as judged by the low level of radio frequency (RF) power required to obtain a 90 degree pulse and the uniformity of the RF field within the resonator pair. A modification of the pair geometry provides for reasonable observation of the tissues through the chest wall and laterally to the axillae. 相似文献