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991.
992.
OBJECTIVE: Prospectively to compare lymphatic drainage after ultrasonic dissection, an electrocoagulation technique and sharp dissection in the groin during surgery for recurrent sapheno-femoral incompetence. DESIGN: Prospective, randomised study comparing three surgical techniques. METHODS: Thirty-six consecutive patients undergoing surgery for recurrent sapheno-femoral incompetence were randomised. Twelve patients underwent dissection with ultrasound, 12 with electrocoagulation and 12 controls had sharp dissection with ligation of scar and lymphatic tissue using absorbable suture material. RESULTS: The mean drain output per patient was 13.5 ml in the ultrasonic group, 15.4 ml in the electrocoagulation group and 8.3 ml in the suture ligation group. Six minor cases of lymphatic leakage occurred in the ultrasonic group. This resulted in no clinical problem. There were no other significant differences between the three groups. CONCLUSIONS: There is no detectable advantage for the use of ultrasound or electrocoagulation in recurrent saphenous high ligation compared to sharp dissection.  相似文献   
993.
Results of total and subtotal colon resections in children.   总被引:2,自引:0,他引:2  
AIM: The treatment of long-segment neuronal intestinal malformations confronts the paediatric surgeon with the problems of diagnosis, suitable surgical methods and postoperative care. The evidence based only on ganglion cells is inadequate to decide about the required extent of resection and does not exclude hypoganglionosis and disseminated dysganglionosis. For the surgical treatment, pouch procedures as well as the usual resection techniques according to Rehbein, Soave, and Duhamel are discussed. Since studies with greater numbers of patients are rare, we present here our own results. METHODS: 48 patients with long segment intestinal malformations were treated in our hospital between 1990 and 2000. A total of 35 patients were examined 1.5-6 years after definitive surgical therapy. Rehbein's anterior resection was performed in all cases. RESULTS: Our findings showed that the surgical treatment with Rehbein's technique offers good results, both with respect to complications as well as to the postoperative course, although a 4 cm long aganglionic segment remains in situ. We found that results were better after ascendorectostomy (n = 22) compared to ileorectostomy (n = 11). Earlier publications of this group (13) show that the histology of the proximal resection margin is decisive for the prognosis. Hypo- and aganglionic segments should be completely resected while short IND segments of the colon or terminal ileum may remain in situ. However, the additional effect of the aganglionic segment of the distal rectum and the decreased peristaltic flow of the pre-anastomotic bowel has to be taken into account. Further investigations are required to find out whether a combination of Soave's endorectal pull-through with a remaining neuronal dysplastic segment proximal to the resection margin may give better results or if the frequency of postoperative enterocolitis and incontinence increased in cases of long segment intestinal neuronal malformations. Accurate diagnosis of myenteric plexus is decisive for an optimal treatment and therefore, considering our results, it is essential that in case of newborns getting to hospital with colon obstruction and suspicion of neuronal intestinal malformation full thickness biopsies from the distal and proximal colon may be taken simultaneously with the enterostomy. Generally ileostomy is performed in patients suspected of long-segment neuronal intestinal malformations. Mucosa suction biopsies from the distal and proximal stoma side are less informative compared to full thickness biopsies.  相似文献   
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Using fura-2 loaded neural tumour cells, SK-N-SH, we demonstrate that receptor-mediated activation of phosphoinositide hydrolysis not only causes the release of Ca2+ from intracellular stores but also causes a concomitant influx of extracellular Ca2+. Thapsigargin (TG), a sesquiterpene lactone, causes a sustained elevation of intracellular Ca2+ and depletion of the inositol 1, 4, 5-trisphosphate-sensitive intracellular Ca2+ stores. In the absence of extracellular Ca2+, the increase in intracellular Ca2+ concentration ([Ca2+]i) was transient, suggesting that thapsigargin activates both intracellular mobilization and the influx of Ca2+ from extracellular space. These results are consistent with the proposal that the depletion of the inositol 1, 4, 5-trisphosphate-sensitive intracellular Ca2+ pool serves as a signal for Ca2+ influx.  相似文献   
998.
Previous pharmacological studies with the pituitary gland have suggested that acetylcholine (ACh) might be involved in the regulation of intermediate lobe (IL) function. Whether ACh is endogenous to the IL cells or provided from an extrinsic source is unclear. The present experiments tested the possibility that the endocrine cells of the IL may be a source of ACh by measuring certain cholinergic markers in a primary culture of dissociated porcine cells. The endogenous ACh content was readily measurable in both the freshly dissociated IL cells and in 2- or 4-day primary cultures. Choline acetyltransferase activity was also measurable in the freshly dissociated and cultured IL cells and was reduced by 53% in the presence of a specific inhibitor, napthylvinylpyridine (50 μM). IL cells incubated in the presence of [14C]choline (1 μM) were able to synthesize [14C]ACh and the accumulation of the new ACh was inhibited by hemicholinium-3 (30 μM), a competitive inhibitor of high affinity choline uptake at cholinergic nerve terminals. In conclusion, these results demonstrate that the endocrine cells of the IL are capable of synthesizing and storing ACh.  相似文献   
999.
Using liposomes radiolabelled by the 99mTechnetium-stannous chloride technique we have investigated the effect of surface charge on the stability of the isotope in vitro and in vivo. Dialysis of 99mTc-labelled positive, negative and neutral liposomes, which had been incubated in either saline or normal rat serum showed no significant loss of the isotope from the liposome surface with only 2 per cent of the isotope dialysed. A comparison of gel chromatography with dialysis confirmed that most of the isotope remained attached to the liposome surface, but it did reveal greater loss of the isotope, between 15 and 23 per cent. The liposome clearance rates obtained from 125I-egg phosphatidylcholine (EPC) and 99mTc dual-labelled positive or neutral liposomes were significantly different. The 99mTc marker was cleared five times faster from the positive liposomes and twice as fast from the neutral liposomes as the 125I-EPC integral membrane marker. The 99mTc attached to liposomes with a negative surface charge was stable in vivo and had the same clearance rate from the circulation as the 125I-EPC marker. These results indicate that the commonly used in vitro techniques for assessing liposome radiolabel stability are unsuitable for predicting the stability of the 99mTc in vivo.  相似文献   
1000.
Several substances can interfere with microtubular function eg. colchicine. Melatonin, a hormone secreted by the pineal gland has similar effects as colchicine on microtubules. In this study melatonin levels were determined in both plasma and seminal plasma of patients with good or impaired motility and forward progression. There was no statistically significant difference between the mean plasma and seminal plasma values of patients with good or impaired motility and forward progression. There was no correlation between seminal plasma melatonin and impaired motility or any other semen parameter. There was also no correlation between plasma and seminal plasma concentrations of melatonin. High seminal plasma melatonin concentrations were not necessarily associated with impaired sperm motility. From these it is concluded that seminal plasma melatonin plays no important role in sperm motility.  相似文献   
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