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21.
Abstract: This paper dicusses the use of esophageal dilatation with a Rigiflex TTS balloon. This method was used 45 times on 11 patients affected by anastomotic or a severe grade peptic esophageal stenosis. Fluoroscopic guidance was used in 36 procedures (80%) without effecting the mean duration of the treatment (12 minutes). The results were considered satisfactory when these goals had been achieved: a) dilatation of the stenosis over 15 mm; b) a dysphagia free-time of more than 6 months. A satisfactory result was achieved in 10 patients (90.9%), without deaths and major complications. 5 patients received 1 dilatation and the other 5 needed, 3-3-4-7–11 procedures respectively to obtain a satisfactory result. On these basis we consider that its great efficacy, security and tolerability depend on the following characteristics of the Rigiflex TTS balloon: 1) “radial” dilatation; 2) the possibility of introducing the balloon through the operative channel of the fiberscope; 3) direct visualization of the stenosis during dilatation. The following disadvantages with this method are: the absence of a tactile sensation of dilatation and the elevated cost of the instrument. We conclude that the Rigiflex TTS balloon is an important alternative to guide-wire techniques, especially for the treatment of severe esophageal strictures. 相似文献
22.
妊娠肝内胆汁淤积症患者血清一氧化氮和内皮素的变化及意义 总被引:2,自引:0,他引:2
目的:探讨妊娠肝内胆汁淤积症(ICP)患者外周静脉血清、新生儿脐静脉血清中一氧化氮(NO)、内皮素(ET)、丙二醛(MDA)和超氧化物歧化酶(SOD)含量的变化及在ICP发病中的作用。方法:以ICP组28例为研究组,测定其外周静脉血清及新生儿脐静脉血清中的NO、ET、MDA和SOD,以年龄相近的24例正常孕妇作为对照组。结果:ICP患者的MDA和ET含量较正常晚期妊娠显著增高(P<0.01),ICP患者的NO和SOD含量与对照组相比无显著性差异(P>0.05)。母血清中NO、ET、MDA含量均较新生儿脐静脉血清中的含量高,差异有显著性(P<0.01)。结论:妊娠期体内氧化和抗氧化失衡及ET水平的增高可能与ICP的发生、发展有关。 相似文献
23.
Intra-lesional injections of collagenase are ineffective in the treatment of keloid and hypertrophic scars. 总被引:2,自引:0,他引:2
Norbert Kang Branavan Sivakumar Roy Sanders Charles Nduka David Gault 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(7):693-699
The treatment of keloid and hypertrophic scars remains difficult. Enzymatic digestion of keloid scars has been previously proposed as an effective treatment strategy for reducing the volume of keloid scars. To test this, we administered intra-lesional injections of pure collagenase (between 600 and 4500 units for each scar) into the keloid and hypertrophic scars of seven human volunteers (five keloid and two hypertrophic scars). Five patients (three keloid and two hypertrophic) received more than one injection of collagenase. The treatment resulted in a temporary reduction in scar volume for three of the patients with keloid scars. However, scar volumes for these three patients returned to the same (or greater) levels after 6 months of follow-up. Treatment with collagenase produced no change in scar volume for the two patients with hypertrophic scar. Side effects were numerous and severe including; pain, swelling, blistering, ulceration and ecchymosis at the site of injection. One patient required admission to hospital for 48 h after the first injection. Maximum length of follow-up was 6 months. None of the seven patients completed the study and returned for final follow-up at 2 years. This pilot study suggests that treatment of keloid and hypertrophic scars with intra-lesional injections of collagenase is ineffective. 相似文献
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25.
Incidence of retinal detachment following posterior chamber intraocular lens surgery 总被引:9,自引:0,他引:9
We examined the three-year incidence of retinal detachment in a consecutive cohort of 4,329 eyes which had cataract surgery with implantation of a posterior chamber intraocular lens between 1979 and 1984. The overall three-year incidence was 1.4%. The three-year incidence for open capsule cases (1.9%) was over twice that for intact capsule cases (0.8%). Axial myopes (axial length greater than or equal to 25 mm) overall were at least three times as likely to develop retinal detachment within three years (3.6%) as eyes with axial lengths less than 25 mm (1.1%). The combination of open capsule and axial myopia increased the three-year retinal detachment risk tenfold over that of the intact capsule in normal length eyes. 相似文献
26.
Retinoblastoma in Great Britain 1969-80: incidence, treatment, and survival. 总被引:7,自引:5,他引:2 下载免费PDF全文
Patients with retinoblastoma diagnosed from 1969 to 1980 have been followed up for periods of up to 17 years. Data from a previous study of patients diagnosed from 1962 to 1968 have been included for analysis of incidence and second primary tumours, and for study of trends in treatment. The registration rate in Britain (which may be about 10% less than the true incidence) is about one in 23,000 live births, approximately 40% of cases being known to be genetic. There is no apparent trend in incidence during the period covered by these two studies. The three-year survival rate in 88%. Patients with bilateral tumours have a better survival rate than those with unilateral tumours for the first few years, but their long-term survival rate is worse because of later deaths from ectopic intracranial retinoblastoma or second primary neoplasms. Older children tend to have a worse prognosis, which is related to the fact that their tumours are diagnosed at a more advanced stage. There is a significantly higher survival rate for boys than for girls; this is partly accounted for by difference in age and stage at diagnosis between the sexes. Children referred to units specialising in the treatment of retinoblastoma have a higher three-year survival rate than those treated at other hospitals. Comparing methods of treatment between the periods 1962-8 and 1969-80, we find there has been a trend towards more conservative treatment. The use of chemotherapy is now usually reserved for recurrences and metastases and for palliative treatment in terminal retinoblastoma. 相似文献
27.
The growth and development of vegan children 总被引:1,自引:0,他引:1
The results of prospective study on the growth and diets, estimated from 7-day weighed food intake records, of 20 life vegan children (aged 5.8–12.8 years) are presented. The growth and development of the children were normal but they tended to be lighter in weight and exceptionally lean compared with standards. Heights were around the median of the Tanner-Whitehouse standards but were lower than the medians recently proposed by the Department of Health. Energy intakes were similar to those reported in children of the same age in the general population, but dietary fibre intakes were very high which may have influenced the digestible energy. Sugar provided an average 15.6% of the dietary energy and this was supplied mainly by fruit and fruit juice. Mean fat intakes were close to the dietary reference values. Daily intakes of essential nutrients generally met the amounts recommended, with the exceptions of calcium and vitamin B12 . Many children received supplementary sources of vitamin B12 and only two children had intakes below the lower recommended nutrient intake. Intakes of saturated fatty acids were low and those of linoleic acid were high. The ratio of linoleic/α-linolenic acid was high. As docosahexaenoic acid is absent from vegan diets, it is suggested that vegans should use oils with a lower ratio of linoleic/α-linolenic acid. Future studies should also consider the influence of a vegan diet on retinal function. None of the children was immunized against whooping cough and 11 had not been immunized against polio: 16 of the children had suffered from whooping cough. Future studies need to take into account factors other than diet when assessing the health of vegans. The results of this study show that children can be successfully reared on a vegan diet providing sufficient care is taken to avoid the known pitfalls of a bulky diet and vitamin B12 deficiency. 相似文献
28.
Increase in membrane uptake of long-chain fatty acids early during preadipocyte differentiation. 总被引:5,自引:1,他引:4 下载免费PDF全文
N A Abumrad C C Forest D M Regen S Sanders 《Proceedings of the National Academy of Sciences of the United States of America》1991,88(14):6008-6012
An increase in early rates of oleate uptake, which reflected fatty acid (FA) entry into the cells, was apparent 2-3 days after confluence of differentiating BFC-1 preadipocytes. The increase was measured in cells kept without glucose and with arsenate, where greater than 95% of intracellular radioactivity was recovered as free unesterified oleate. Uptake of retinoic acid, a molecule structurally similar to long-chain FA, remained unaltered during cell differentiation. Increase in oleate transport was related to increase in transport Vmax (determined under arsenate treatment) from 0.2 to 2 nmol/min per 10(6) cells, whereas Km remained unchanged (2 x 10(-7) M). Oleate transport was maximal at about day 6 after cell confluence (day 0), as FA metabolism (incorporation into lipids) began to gradually increase. The increase in transport preceded induction of mRNAs for both cytosolic FA-binding protein, which appeared at day 6, and for the FA synthase, which appeared at day 10. Data indicated that increases in activities of FA transport and of lipoprotein lipase, early during cell differentiation, favored increased availability of exogenous FA at a stage when endogenous FA synthesis is limited. This result would promote FA esterification and lipid deposition by supplying a rate-limiting substrate. Furthermore, oleate addition to BFC-1 preadipocytes at confluence potentiated the effect of dexamethasone in inducing mRNA for cytosolic FA-binding protein. In adipocytes, FA from exogenous or endogenous sources was necessary to maintain levels of cytosolic FA-binding protein mRNA. Thus, the increase in FA availability might contribute to, or modulate, induction of proteins necessary for preadipocyte differentiation. 相似文献
29.
30.
This paper focuses on eosinophil activation and its selective inhibition. Superoxide anion (O2-) production by human eosinophils, an indicator of their activation, was induced by a variety of activators. Several compounds which are known to inhibit protein kinase C (staurosporine, K252a, sphingosine) inhibited O2- production induced by phorbol ester (PMA) but failed to inhibit O2- production induced by IgG coupled to Sepharose beads. Inhibition of O2- production by other agents (plasma-activated zymosan, fMLP, and leukotriene B4 (LTB4), was intermediate. By contrast, wortmannin, a compound which has been previously reported to inhibit O2- production in neutrophils via a protein kinase-independent pathway, potently inhibited O2- production in eosinophils which had been activated by IgG and by Platelet-Activating Factor but was virtually inactive against PMA-induced O2- production. Taken together, the results indicate that, as a minimum, there must be two pathways of induction of O2- production in eosinophils. Moreover, the intermediate levels of inhibition in cells which had been activated with serum-activated zymosan, FMLP, and LTB4 suggest that these agents may either be acting via both of these pathways or that yet other pathways may exist. 相似文献