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991.
A review is presented about fagaronine, a benzophenanthridine alkaloid responsible for antitumoural activity. Plant source, extraction, biosynthesis, medicinal properties, especially antileukaemic activity, are described. 相似文献
992.
Monitoring of skin response to sodium lauryl sulphate: clinical scores versus bioengineering methods
The present trial was designed to evaluate clinical scores (single observer) of sodium lauryl sulphate (SLS)-induced skin irritation in a group of subjects (n = 10) over a 10-day period along with various skin function parameters. In order to avoid significant variations due to secondary phenomena, the following parameters were recorded with non-invasive instruments in this order: skin capacitance (C1; arbitrary units; CM420 Corneometer), transepidermal water loss (TEWL; g/m2.h; Evaporimeter) and laser Doppler flowmetry (CBFV: cutaneous blood flow values; Periflux). All examinations were performed during winter on reclined relaxed subjects present for at least 10 min in a test room with controlled temperature and relative humidity (t degrees: 19.5-20.7 degrees C and RH: 47.3-60.3%). The analysis of differential data (delta = value at tx-value before test; 2-way ANOVA) was made on single parameters as a function of site (volar forearm versus neck) and time (from 24 h after 48-h occlusion with 5% SLS up to 10 days later). The profile of erythema scores over time differed between neck and forearm, but the delta CBFV readings with the laser Doppler instrument did not detect significant site-time interactions. Roughness (blind evaluation with palpating finger) and capacitance readings (delta C1) showed significant differences between sites, but the profile over time was similar in both locations. delta TEWL did not differ according to anatomical location. The reason for different erythema scores on neck and forearm might be related to inherent regional variation of optical properties of the skin or to a substantial contribution of SLS-induced roughness to the readings of erythema.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
993.
994.
Ostial PV Isolation: 总被引:2,自引:0,他引:2
SABINE ERNST MATTHIAS ANTZ FEIFAN OUYANG THOMAS VOGTMANN MASAHIKO GOYA DIETMAR BÄNSCH ANSELM SCHAUMANN KARL-HEINZ KUCK 《Pacing and clinical electrophysiology : PACE》2003,26(7P2):1624-1630
Pulmonary vein (PV) isolation by elimination of spike potentials has been reported to cure drug refractory atrial fibrillation. Because of the heterogenous morphology of the PVs, sequential electroanatomic reconstruction of the PVs was performed in 39 patients (group A), who underwent subsequent PV isolation by interruption of all conductive myocardial fibers by distinct RF current applications using a "lasso" approach. In group B (157 patients), only biplane two-dimensional fluoroscopy was performed to guide the diagnostic and the ablation catheters. After reprocedures (in 7% of patients in group A and 22% of group B), which depicted a recurrence of a spike potential inside or at the ostium of >1 previously isolated PV in all restudied patients, stable sinus rhythm was documented in 69% of patients in group A and 60% of patients in group B. Reasons for the relapse of the previously eliminated spike potentials include a temporary ablation effect and a too distal interruption of the conducting myocardial fiber. Detailed knowledge of the individual three-dimensional morphology enhanced the clinical success rate of PV isolation but is time-consuming using CARTO (8.0 ± 1.7 vs 5.0 ± 1.6, P < 0.001) . Further technical improvement to fuse the individual three-dimensional anatomy and the electrophysiological markers to a composed "electroanatomic" map may overcome this limitation in the future. (PACE 2003; 26[Pt. II]:1624–1630) 相似文献
995.
996.
本文用30例成人尸体观察了动脉韧带和左喉返神经,动脉韧带长1.2.97±4.53mm,圆索状动脉韧带23例(77%),直径为3.92±1.12mm。动脉韧带的主动脉端附着于主动脉弓(80%)或降主动脉(20%),肺动脉端附着于左肺动脉,6例肺动脉端位于心包内。19例(63%)左喉返神经绕主动脉弓,11例(37%)绕动脉韧带的主动脉端。 相似文献
997.
Fetal diagnosis has vastly improved over the last decade. Ultrasound has become the imaging modality of choice. As real-time
equipment has improved technologically, the ability to deduce subtle abnormalities has greatly increased.
The fetal genitourinary tract may be evaluated for renal dysplasias, anomalies, or obstruction. Points of obstruction and,
at times, the exact cause of obstruction may be deduced. Abnormalities of the ureter, bladder, urethra, scrotum, or reproductive
system can be detected. 相似文献
998.
G. Vinçon C. Baldit P. Couzigou F. Demotes-Mainard L. Elouaer-Blanca Dr. B. Bannwarth B. Begaud 《European journal of clinical pharmacology》1992,43(5):559-562
Summary The pharmacokinetics of famotidine has been investigated in ascitic cirrhotic patients. 10 decompensated cirrhotic patients were studied (9 m, 1 f), who had normal renal function, and six healthy control subjects (4 m, 2 f), matched for age, sex and weight. Each subject received on two occasions, at least four days apart, a single oral (40 mg) or intravenous dose (20 mg) of famotidine, at 21.00 h in a randomised manner. Serial blood samples were collected and famotidine in plasma was determined by a HPLC/UV method. Plasma data were subjected to non compartmental pharmacokinetic analysis.There were no statistically significant differences in pharmacokinetic parameters between the two groups after either the intravenous or oral administration of famotidine.The findings suggest that the dose of famotidine may not require any adjustment in ascitic patients without renal failure. 相似文献
999.
The peri-operative course of 194 patients undergoing 244 procedures for primary repair of cleft lip and palate over an 8-year-period was studied. A marked increase in the extent of intra-operative monitoring was noted during this period. The Pierre Robin syndrome was the most common associated abnormality and was found in 17% of patients in this series. There were no deaths. A total of 101 procedures were undertaken in infants with cleft lip of whom 10% received an intra-operative blood transfusion. Post-operative opiate analgesics were administered following 97% of these procedures and profound respiratory depression was observed in three children. The use of lignocaine and noradrenaline did not significantly reduce the operative blood loss. A post-operative pyrexial illness was significantly associated with the presence of a positive pre-operative nasal and throat swab and this could be significantly reduced by pre-operative antibiotic treatment. A total of 143 children underwent repair of cleft palate and of these 16.8% received an operative blood transfusion. An elective tracheostomy was required in one patient because of unsuccessful attempts at endotracheal intubation. One patient developed a respiratory arrest after two doses of diamorphine peri-operatively. The use of lignocaine and noradrenaline significantly reduced the operative blood loss. The presence of a positive bacteriological nose or throat swab did not influence the development of a post-operative pyrexia which could however be significantly reduced by the use of pre-operative antibiotics. 相似文献
1000.
Lothar SCHRAMM Josef ZIMMERMANN Kai LOPAU Hong LING Joachim HARLOS Ekkehart HEIDBREDER 《Nephrology (Carlton, Vic.)》1995,1(3):241-250
Summary: Calcium channel blockers are able to improve renal function in acute renal failure (ARF) and natriuretic peptides can also exert beneficial effects. At present it is unknown whether administration of atrial natriuretic peptide (ANP) and a calcium channel blocker given before a toxic lesion can prevent gentamicin induced ARF. the mechanisms of action of natriuretic peptides and calcium channel blockers are different and, as yet, it has not been clarified if combined administration can augment the effects on renal function. After a basal period we investigated the effects of verapamil (VER, 0.66 mg/kg), ANP, (30 μg/kg) and a combination of both (identical doses as described individually). the drugs were given intravenously for a period of 40 min (infusion period) before gentamicin (15 mg/kg, i.v.) was administered for induction of ARF. Basal values for glomerular filtration rate (GFR, mL/min) were around 1.8 with no differences between the groups. At the end of the infusion period (before application of gentamicin) GFR was significantly elevated with VER + ANP (3.13 ± 0.51), ANP (2.70 ± 0.59) and VER (2.34 ± 0.47) compared to controls (saline, 1.7 ± 0.48). After application of gentamicin GFR significantly dropped in the control group (0.77 ± 0.21, 0.75 ± 0.19, respectively), indicating development of ARF. In contrast with VER + ANP, ANP and VER GFR could be maintained for 30 min (2.47 ± 0.39, 2.28 ± 0.33, 2.22 ± 0.43, respectively) and 130 min (2.11 ± 0.32, 1.86 ± 0.29, 2.11 ± 0.28, respectively) after gentamicin. Moreover ANP and VER revealed natriuretic activity and, due to their vasorelaxing potency, also influenced arterial blood pressure. We conclude that both VER and ANP are able to prevent early gentamicin induced ARF when given before the toxic lesion. Both drugs induce hyperfiltration while infused, in particular when administered in combination. 相似文献