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91.
Abstract— Ecto ATP-diphosphohydrolase (apyrase) activity of human endothelial cells following aspirin treatment has been studied in-vitro. It was shown by HPLC analysis of supernatant samples that pre-incubation of the cultures with aspirin resulted in a significantly increased turnover of supplemented ATP into its degradation products (ADP and AMP). Enhanced expression of ectoenzyme after aspirin treatment could be observed as demonstrated by immunofluorescence-staining with monoclonal anti-apyrase antibodies. This suggests enhancement of endothelial ATP-diphosphohydrolase activity induced by aspirin. The present data obtained in human vascular cells in-vitro are in line with results from previous animal studies in-vivo, suggesting a novel cyclo-oxygenase-independent antithrombotic activity of aspirin.  相似文献   
92.
93.
A new education package covering every aspect of the management of chemotherapy- and radiotherapy- induced emesis is currently being produced by the International Society of Nurses in Cancer Care in collaboration with Glaxo. It is intended to have wide application and can be used as a distance-learning package by nurses working alone, or is also suitable for use in lectures, seminars and group teaching. The whole package is, therefore, presented as a manual for individual use accompanied by a set of slides and lecture notes.  相似文献   
94.
N-Cyclohexyl-N′ -isopropylcarbodiimide was prepared and used for peptide couplings by various procedures. Reaction between Z-Val and Gly-OEt was used for yield studies and determination of the extent of the side reaction in solution. The value of this reagent for solid peptide synthesis was demonstrated by the synthesis of sequences comprising the 65–74 residues of acyl carrier protein. The efficiency of activation was determined by competition experiments. From all these studies the conclusion can be drawn that N-cyclohexyl-N′-isopropylcarbodiimide is comparable to or even better than the commonly used DCC for mediation of peptide bond formation in solid phase synthesis. By virtue of the solubility of N-cyclohexyl-N′-isopropylurea in dichloromethane, the carbodiimide seems to be a good candidate for practical execution of peptide bond formation by the standard carbodiimide procedure.  相似文献   
95.
MACLE, L., et al. : Radiation Exposure During Radiofrequency Catheter Ablation for Atrial Fibrillation. RF catheter ablation of paroxysmal atrial fibrillation (PAF) is associated with prolonged fluoroscopy. The procedural duration and fluoroscopic exposure to patients and medical staff were recorded and compared among 43 ablation procedures for PAF, 20 for common atrial flutter, and 16 for accessory pathways. Patient radiation exposure was measured by dosimeters placed over the xyphoid, while that of physicians and nurses was measured by dosimeters placed outside and inside the lead apron. The mean fluoroscopy time was   57 ± 30   minutes for PAF,   20 ± 10   minutes for common flutter, and   22 ± 21   minutes for accessory pathway ablation. The patient median radiation exposure was 1110μSv for PAF, compared with 500 μSv for common flutter and 560 μSv for accessory pathway ablation (P < 0.01). The median radiation exposure to physician and nurse inside the lead apron were, respectively, 2 μSv and 3 μSv for PAF, 1 μSv and 2 μSv for common flutter, and <0.5 μSv and 3 μSv for accessory pathway ablations. RF catheter ablation for PAF was associated with prolonged fluoroscopy times and a twofold higher radiation exposure to the patient and physician compared with other ablation procedures. Assuming 300 procedures/year, radiation exposure to the medical staff was below the upper recommended annual dose limit. (PACE 2003; 26[Pt. II]:288–291)  相似文献   
96.
Abrupt occlusion of the coronary artery during PTCA is a relatively common complication. The majority of the acute occlusions occur when there is a significant dissection at the site of the balloon expansion. The use of a temporary stent, which can be expanded and collapsed intraluminally, allowing repositioning and finally removal of the device, is reported in this article.  相似文献   
97.
Cost Analysis of Catheter Ablation for Paroxysmal Atrial Fibrillation   总被引:1,自引:0,他引:1  
WEERASOORIYA, R., et al. : Cost Analysis of Catheter Ablation for Paroxysmal Atrial Fibrillation . RF ablation for paroxysmal atrial fibrillation (PAF) is a curative treatment, which when successful, eliminates the need to take antiarrhythmic drugs, be anticoagulated, and have recurrent physician visits or hospital admissions. The authors performed a retrospective cost comparison of RF ablation versus drug therapy for PAF. The study population consisted of 118 consecutive patients with symptomatic, drug refractory PAF who underwent   1.52 ± 0.71   RF ablation procedures (range 1–4) for PAF. During a follow-up of 32 ± 15 weeks, 85 (72%) patients remained free of clinical recurrence in absence of antiarrhythmic drugs. The cost of RF ablation was calculated in the year 2001 euros on the basis of resource use. The mean cost of pharmacologic treatment prior to ablation was 1,590 euros/patient per year. The initial cost of RF ablation for PAF was 4,715 euros, then 445 euros/year. After 5 years, the cost of RF ablation was below that of ongoing medical management, and continued to diverge thereafter. RF catheter ablation may be a cost-effective alternative to long-term drug therapy in patients with symptomatic, drug refractory PAF. (PACE 2003; 26[Pt. II]:292–294)  相似文献   
98.
99.
Postoperative ileus is a common complication after intra-abdominal surgery. Nitric oxide produced by macrophages in the inflamed gastrointestinal tract plays a crucial role in the pathogeny of postoperative ileus. Honokiol, extracted from the bark of Magnolia spp., is a natural compound with a biphenolic structure. In the present study, we examined the effect of honokiol on postoperative ileus and discussed its site of action. Postoperative ileus model mice were generated by surgical intestinal manipulation. Mice were administered honokiol (10 mg kg?1, per os) 1 h before and after intestinal manipulation. Gastrointestinal transit, leukocyte infiltration, and messenger RNA (mRNA) expression of inflammatory mediators were measured in postoperative ileus model mice with or without honokiol. We also investigated the inflammatory effect of honokiol in lipopolysaccharide-stimulated peritoneal macrophages. Gastrointestinal transit was delayed in postoperative ileus model mice and honokiol recovered the impaired transit. Honokiol significantly inhibited leukocyte infiltration and upregulation of proinflammatory cytokines (tumor necrosis factor-α, interleukin-1β, and interleukin-6) and inducible nitric oxide synthase in the ileal muscle layer of postoperative ileus model mice. In peritoneal macrophages activated by lipopolysaccharide, honokiol significantly inhibited the upregulated mRNA expression of proinflammatory cytokines and inducible nitric oxide synthase. Honokiol significantly recovered gastrointestinal dysmotility and inhibited intestinal inflammation in postoperative ileus. Moreover, honokiol was suggested to have effects on macrophages, namely, inhibiting mRNA expression of proinflammatory cytokines and inducible nitric oxide synthase. Taken together, honokiol represents a potential novel therapeutic agent for postoperative ileus.  相似文献   
100.
A case of male pseudohermaphroditism aged 48 years with systemic hypertension and hypokalaemic alkalosis is described. Results of metabolic studies point to a 17alpha-hydroxylase deficiency demonstrated by low cortisol (0-56 mg/24 h), high corticosterone (270 mg/24 h) and 11-deoxycorticosterone (5 mg/24 h) secretion rates. Adrenocorticotrophin and gonadotrophin levels were markedly raised but plasma androstenedione (3 ng/dl), testosterone (17 ng/dl), oestrone (3 ng/dl) and oestradiol(1-8 ng/dl) were all low. Plasma aldosterone levels and secretion rates in urine were low and were surprisingly unaffected by dexamethasone therapy although low renin levels rose with a marked return of the erect posture effect. Therapeutic levels of dexamethasone were, however, followed by incipient renal failure.  相似文献   
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