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991.
New thin layer densitometry and high performance liquid chromatography (HPLC) methods are described for quantitative determination of glafenine in dosage forms in the presence of its photo-degradation products and in serum in the presence of its metabolites. Mobile phases consisting of toluene-isopropyl alcohol-dimethylformamide-water (18:3:1:0.5) and methanol-water-phosphoric acid (80:120:0.5) are found to be efficient for reasonable separation and adequate resolution of glafenine from associated substances by thin layer chromatography (TLC) and HPLC techniques, respectively. The methods are used for the study of glafenine purity, stability, bioavailability, bioequivalence and tablet dissolution rate. The results obtained by TLC and HPLC techniques are in good agreement and offer the advantages of reproducibility and accuracy. 相似文献
992.
Detection of Cr(V) in the reduction of Cr(VI) by whole live mice and its characterization were carried out by low frequency electron paramagnetic resonance (EPR). Intravenous injection of Cr(VI) to mice generated Cr(V). The Cr(V) was found predominantly in the liver with a small amount in the blood. Liver homogenates from Cr(VI) treated mice generated essentially the same Cr(V) spectrum as that obtained from the whole live mice. This Cr(V) species was identified to be a Cr(V)-nicotinamide adenine dinucleotide (NAD) (P)H complex with an oxygen bond to Cr(V). Pretreatment of the mice with ascorbic acid and glutathione reduced the Cr(V) formation, while pretreatment with reduced nicotinamide adenine dinucleotide (NADH) enhanced it. Metal chelators, ethylenediaminetetraacetic acid (EDTA), 1,10-phenanthroline, and diethylenetriaminepentaacetic acid (DTPA) inhibited the intensity of the Cr(V) signal. The results suggest that Cr(V) generated in the whole body of a live animal is a Cr(V)-NAD(P)H complex and NAD(P)H/flavoenzymes and not glutathione or ascorbate as the major one-electron Cr(VI) reductant responsible for observed formation of Cr(V)-NAD(P)H complex in vivo. 相似文献
993.
KA Hoekstra GK Iwama CR Nichols DV Godin KM Cheng 《Canadian Metallurgical Quarterly》1998,2(4):265-272
The health care received from first admission to a pediatric rheumatology clinic to 9-year follow-up was assessed in 109 patients with chronic inflammatory rheumatic diseases or chronic idiopathic musculoskeletal pain. Ninety-five of the patients had received hospital care after the first admission, of whom 53 patients > or = 18 years, 21 patients < 18 years, and 33 parents of patients < 18 years rated their degree of satisfaction with the health care from 0 to 10. Mean scores of satisfaction with different aspects of care ranged from 6.0 to 9.6. Among patients > or = 18 years, those with idiopathic pain were less satisfied than those with inflammatory rheumatic diseases on the availability of care (mean 6.4 vs. 8.5, p < 0.001), continuity of care (mean 6.5 vs. 8.4, p < 0.001), and empathy of the health care providers (mean 6.7 vs. 7.9, p <0.05). The diagnostic group and the occurrence of remission predicted the level of global satisfaction in patients > or = 18 years. In patients < 18 years, chronic family difficulties predicted patient satisfaction and physical disability and chronic family difficulties predicted parent satisfaction. In conclusion, most parents and patients with inflammatory rheumatic diseases were satisfied with the health care. However, some patients with idiopathic pain had unmet needs for care. 相似文献
994.
Insulin, a classic vertebrate hormone, produces alterations in cellular metabolism and growth in the ciliate Tetrahymena pyriformis, as well as an increase in insulin binding upon subsequent exposure, a phenomenon known as hormonal imprinting. An antibody to a peptide corresponding to the alpha-subunit of the human insulin receptor (amino acid residues 657-670) was used to investigate the location and to partially characterize immunoreactive proteins in insulin-exposed and non-insulin-exposed cells (control). Confocal microscopy revealed immunofluorescent labeling of cilia, nuclei, vesicles and an oblong structure of unknown nature. Labeling of nuclei, mitochondria and ciliary microtubules was seen with immunoelectron microscopy. Labeling was absent on the cell and ciliary membranes by immunoelectron microscopy. Polyacrylamide gel electrophoresis revealed several differences in protein composition between control and insulin-exposed ciliary membrane extracts, especially in the 30-50 kDa range. Immunoblotting revealed 2 reactive proteins in whole cell lysates but none were detected in ciliary membrane extracts or wheat germ agglutinin affinity column eluates of T. pyriformis whole cell preparations. Based on these findings it is unlikely that a cell surface structure similar to a mammalian insulin receptor exists in T. pyriformis. 相似文献
995.
GK Jett 《Canadian Metallurgical Quarterly》1996,61(3):1014-1015
Successful left ventricular support is dependent on adequate inflow drainage. We describe atrial cannulation using the dome of the left atrium, which in our experience has resulted in excellent inflow drainage. 相似文献
996.
997.
I Bicik BP Radanov N Sch?fer J Dvorak B Blum B Weber C Burger GK von Schulthess A Buck 《Canadian Metallurgical Quarterly》1998,51(2):345-350
We used radiostereometric analysis to compare wear rates between uncemented porous sockets and cemented all-polyethylene sockets in a series of 102 hips randomised for either a Harris-Galante or a Charnley cup. Wear was evaluated in 95 hips at a mean of five years (2 to 7). All hips had a cemented, 22 mm head mono-bloc Charnley stem. The mean annual wear rate was 0.09 mm in the Charnley sockets and 0.10 mm in the Harris-Galante sockets, with no statistically significant differences in wear, migration or rotation. We conclude that, up to five years, the wear characteristics of the modular and porous Harris-Galante socket resemble that of the Charnley socket. 相似文献
998.
p21waf1 has been shown to mediate the p53-dependent growth arrest induced by DNA-damaging agents. Several functions have been ascribed to p21waf1 that could be involved in this growth arrest. For one, p21waf1 is an efficient inhibitor of cyclin-dependent kinases (CDKs). Also, p21waf1 can interact with proliferating cell nuclear antigen (PCNA), and as such inhibit in vitro DNA-replication. Finally, p21waf1 has been reported to inhibit stress-activated protein kinases (SAPKs). In order to study these multiple functions of p21waf1 we have established U2OS-derived cell lines, in which the expression of p21waf1 can be regulated by the concentration of tetracycline in the culture medium. We observed a virtually complete, but reversible inhibition of cell growth upon induction of p21waf1-expression. Both [3H]thymidine-incorporation and CDK2-activity were strongly inhibited by p21waf1. Upon induction of p21waf1 cells accumulated with a 2N or 4N DNA content suggesting events in G1 and G2 can be inhibited by p21waf1. Indeed, kinase activity associated with cyclin B was reduced dramatically upon induction of p21waf1, although cyclin B continues to be expressed. In contrast, p21waf1 does not seem to inhibit the function of PCNA in ongoing DNA replication, since cells expressing high levels of p21waf1 apparently progressed normally through S-phase. Also, the activity of SAPKs was not substantially affected by the high levels of p21waf1. We conclude that, at least in these U2OS-derived cells, p21waf1 functions as an inhibitor of CDK-activity in G1 and G2, but not as an inhibitor of PCNA or SAPKs. 相似文献
999.
BACKGROUND: Ventricular septal myotomy/myectomy (Morrow procedure) is the standard surgical option for severely symptomatic patients with hypertrophic cardiomyopathy (HCM) and marked basal obstruction to left ventricular outflow due to mitral valve systolic anterior motion. In some patients, however, congenital malformations of the mitral apparatus may be responsible for outflow obstruction; the failure to recognize this morphology before operation could have adverse consequences. METHODS AND RESULTS: We recently evaluated 2 patients with obstructive HCM operated on at Mayo Medical Center in 1997 who demonstrated direct anomalous papillary muscle insertion into the anterior mitral leaflet, producing muscular midcavity obstruction. This anomaly is potentially identifiable with echocardiography by exaggerated anterior displacement of hypertrophied papillary muscles within the left ventricular cavity and the direct continuity between papillary muscle and anterior leaflet associated with a rigid motion pattern of the mitral apparatus. Echocardiographic diagnosis, however, was confused in both patients by the association of systolic anterior motion of the mitral valve, probably produced by freely mobile margins of the mitral leaflet unencumbered by papillary muscle insertion, and in 1 patient probably representing a second and more basal level of obstruction. Because outflow tract morphology was judged unsuitable for conventional myotomy/myectomy, a novel surgical strategy was designed to remove the outflow gradient in which an extensive myectomy trough (wider at its apical than basal extent) was created within the ventricular septum to papillary muscle level; also, in 1 patient, attachment of anterolateral papillary muscle with the lateral free wall was partially severed to increase mobility of the mitral apparatus. After surgery, both patients reported substantial relief of symptoms and improved exercise tolerance and also showed reduced or abolished basal outflow obstruction. CONCLUSIONS: In HCM, outflow obstruction due to anomalous papillary muscle insertion directly into anterior mitral leaflet is challenging to identify but should always be contemplated before operative intervention. This important (but often unsuspected) congenital malformation may require alternative surgical strategies to standard myotomy/myectomy, similar to those described here. 相似文献
1000.
A Cobanoglu GK Thyagarajan JL Dobbs 《Canadian Metallurgical Quarterly》1998,14(1):19-25; discussion 25-6
OBJECTIVE: Recurrent coarctation is a complication which is seen at a consistent rate following all types of repair for coarctation of the aorta. Particularly disappointing late results are reported in younger infants, under 3 months of age. This retrospective analysis was undertaken to compare the outcomes on late follow-up between subclavian flap angioplasty and resection and end-to-end repair, in this age group. METHODS: Over a 12-year period, between 1982 and 1994, 86 infants under 3 months of age underwent surgical repair of coarctation (39 resections and end-to-end repair, and 47 subclavian flap angioplasty procedures). Operative mortality was not significantly different (P = 0.6) between resection and end-to-end repair (5.1%) and subclavian flap angioplasty (8.5%). All operative deaths (six patients) were in infants with associated ventricular septal defects. The mean follow-up for all patients was 7.95 years +/- 4.10 (range 0-14.5 years). The 5-year survival for resection and end-to-end repair was 87 +/- 5%, compared to 75 +/- 7% for subclavian flap angioplasty (P = 0.2). RESULTS: Recurrent coarctation occurred in nine patients who needed reoperation. The reoperation-free rates at both 5 and 10 years for resection and end-to-end anastomosis, and subclavian flap repair were 86 +/- 6% and 90 +/- 5%, respectively. The recurrence in the resection and end-to-end anastomosis group were due to constrictive scarring at the anastomosis, whereas periductal tissue and growth of posterior aortic ridge caused recurrence in the subclavian flap angioplasty group. There were no deaths during reoperation for recurrence. CONCLUSIONS: Both procedures are extremely effective for coarctation repair in young infants and run a similar risk of recurrence, which are due to completely different mechanisms. The surgeon's expertise is the major determinant of outcome. 相似文献