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91.
A prospective study was began in 1973 of the treatment of pathological gastroesophageal reflux and its complications using the round ligament (ligamentum teres) for gastropexy. A total of 116 patients were operated until 1987 and 100 are evaluated (77% over five years postoperation). Diagnostic procedures and surgical indications are evaluated, periodic controls were established including clinical, radiographic and gastroduodenoscopic evaluation. The results obtained in this group were satisfactory following "Frenchay Hospital" of Bristol criteria (94% favorable results) with an estimated endoscopic recurrence of 5%. The mortality was nil and complications were minimal. We conclude that this procedure should be considered among the surgical options for resolving the pathological gastroesophageal reflux and its complications, in view of the minimal morbidity, absence of mortality and excellent results obtained.  相似文献   
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OBJECTIVE: To evaluate the impact of zinc supplementation on the clinical course, stool weight, duration of diarrhoea, changes in serum zinc, and body weight gain of children with acute diarrhoea. DESIGN: Randomised double blind controlled trial. Children were assigned to receive zinc (20 mg elemental zinc per day) containing multivitamins or control group (zinc-free multivitamins) daily in three divided doses for two weeks. SETTING: A diarrhoeal disease hospital in Dhaka, Bangladesh. PATIENTS: 111 children, 3 to 24 months old, below 76% median weight for age of the National Center for Health Statistics standard with acute diarrhoea. Children with severe infection and/or oedema were excluded. MAIN OUTCOME MEASURES: Total diarrhoeal stool output, duration of diarrhoea, rate of weight gain, and changes in serum zinc levels after supplementation. RESULTS: Stool output was 28% less and duration 14% shorter in the zinc supplemented group than placebo (p = 0.06). There were reductions in median total diarrhoeal stool output among zinc supplemented subjects who were shorter (less than 95% height for age), 239 v 326 g/kg (p < 0.04), and who had a lower initial serum zinc (< 14 mmol/l), 279 v 329 g/kg (p < 0.05); a shortening of mean time to recovery occurred (4.7 v 6.2 days, p < 0.04) in those with lower serum zinc. There was an increase in mean serum zinc in the zinc supplemented group (+2.4 v -0.3 mumol/l, p < 0.001) during two weeks of supplementation, and better mean weight gain (120 v 30 g, p < 0.03) at the time of discharge from hospital. CONCLUSIONS: Zinc supplementation is a simple, acceptable, and affordable strategy which should be considered in the management of acute diarrhoea and in prevention of growth faltering in children specially those who are malnourished.  相似文献   
95.
This study was designed to compare the growth of Pakistani schoolchildren in the UK with the 1990 UK growth standards. Measurements of height, weight, and sitting height were performed on 785 Pakistani schoolchildren aged 5-14 years with the mean values for each age and sex being plotted on the UK growth standards. The results were expressed as SD scores relative to the 1990 reference data. The mean height for the boys was only 0.2 SD scores below the mean for the new growth standards with the mean height for the girls being 0.4 SD scores below the mean. The mean values for weight and body mass index were 0.3 and 0.5 SD scores less than the mean for boys and girls respectively. This study demonstrates that the growth of Pakistani schoolchildren in the UK is comparable to the 1990 UK growth standards with only minor differences. It is not safe to assume that short stature or low body weight in a Pakistani child is due to his or her ethnic background.  相似文献   
96.
Adaptive response of human melanoma cells to methylglyoxal injury   总被引:1,自引:0,他引:1  
The effects of methylglyoxal on the growth of a line of human melanoma cells are investigated. Methylglyoxal inhibits cell growth in a dose- dependent manner and causes an increase in glyceraldehyde 3-phosphate dehydrogenase, and glyoxalase 1 and glyoxalase 2 specific activities. The cellular response to increasing concentrations of methylglyoxal in the culture medium is also studied by measuring L-lactate production, reduced-oxidized glutathione levels and apoptotic cell death. Methylglyoxal seems to promote a change of cell population phenotypic repertoire toward a more monomorphic phenotype. In conclusion, methylglyoxal seems to induce an enzymatic cellular response that lowers methylglyoxal levels and selects the most resistant cells.   相似文献   
97.
The hypoxanthine-guanine phosphoribosyl transferase (hprt) locus in 6- thioguanine (TG) resistant T-lymphocytes is a useful target for the study of somatic in vivo mutagenesis, since it provides information about a broad spectrum of mutation. Mutations in the hprt coding region were studied in 124 TG-resistant T-cell clones from 38 healthy, non- smoking male donors from a previously studied population of bus maintenance workers, fine-mechanics and laboratory personnel. Their mean age was 43 years (range 23-64) and their hprt mutant frequency was 9.3 +/- 5.2 x 10(-6) (mean +/- SD, range 1.4-22.6 x 10(-6)). Sequence analysis of hprt cDNA identified 115 unique mutations; 76% were simple base substitutions, 10% were +/-1 bp frameshifts, and 10% were small deletions within exons (3-52 bp). In addition, two tandem base substitutions and one complex mutation were observed. Simple base substitutions were observed at 55 (20%) of 281 sites known to be mutable in the hprt coding sequence. The distribution of these mutations was significantly different than would be expected based upon a Poisson distribution (P < 0.0001), suggesting the existence of 'hotspots'. All of the 87 simple base substitutions occurred at known mutable sites, but eight were substitutions of a kind that have not previously been reported at these sites. The most frequently mutated sites were cDNA positions 197 and 146, with six and five independent mutations respectively. Four mutations were observed at position 131, and three each at positions 143, 208, 508 and 617. Transitions (52%) were slightly more frequent than tranversions (48%), and mutations at GC base pairs (56%) more common than mutations at AT base pairs (44%). GC > AT was the most common type of base pair substitution (37%). The majority of the mutations at GC base pairs (78%) occurred at sites with G in the non-transcribed strand. All but one of eight mutations at CpG- sites were of the kind expected from deamination of methylated cytosine. Deletion of a single base pair (-1 frameshift) was three times more frequent than insertion of a single bp (+1 frameshift). Almost half (6/13) of the small (3-52 bp) deletions within the coding sequence clustered in the 5' end of exon 2. Short repeats and other sequence motifs that have been associated with replication error were found in the flanking regions of most of the frameshifts and small deletions. However, several differences in the local sequence context between +/-1 frameshift and deletion mutations were also noticed. The present results identify positions 197, 146 and possibly 131 as hotspots for base substitution mutations, and confirm previously reported hotspots at positions 197, 508 and 617. In addition, the earlier notion of a deletion hotspot in the 5'end of exon 2 was confirmed. The observations of these mutational cluster regions in different human populations suggest that they are due to endogeneous mechanisms of mutagenesis, or to ubiquitous environmental influences. The emerging background spectrum of somatic in vivo mutation in the human hprt gene provides a useful basis for comparisons with radiation or chemically induced mutational spectra, as well as with gene mutations in human tumors.   相似文献   
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Phenobarbital and clofibrate, two non-genotoxic carcinogens, have been investigated regarding the relationship between reactive oxygen species, antioxidant enzyme expression and apoptosis in primary cultures of rat hepatocytes. Low toxicity concentrations, 200 and 100 microg/ml for phenobarbital and clofibrate respectively, were used to examine their effect on spontaneous or transforming growth factor beta1 (TGFbeta1)-induced apoptosis and on the expression of antioxidant defence enzymes (superoxide dismutases and catalase). The increased incidence of apoptotic nuclei was visualized in TGFbeta1-treated cultures with the fluorescent dye Hoechst 33258 and was quantified under all experimental conditions by measurement of the hypodiploid peak in DNA histograms obtained by flow cytometry. Both substances, when added separately to hepatocyte cultures and incubated for 24 and 48 h, significantly diminished spontaneous apoptosis and exhibited a slight suppression of TGFbeta1-induced apoptosis. Endogenous peroxide production by hepatocytes increased with TGFbeta1, phenobarbital or clofibrate and the increase was greater with phenobarbital and in the presence of TGFbeta1 with both drugs. Gene expression of catalase and Mn- and Cu,Zn superoxide dismutases (SOD) was evaluated by northern blot analysis of hepatocytes incubated in the presence of phenobarbital or clofibrate with or without TGFbeta1 and the following differences were detected: phenobarbital induced a significant decrease in both dismutases (to 56%, P < 0.05, and 55%, P < 0.05, for Mn- and Cu,Zn-SOD respectively) and a 2-fold increase (P < 0.01) in catalase; clofibrate induced a slight decrease in both SODs and a 4-fold increase (P < 0.05) in catalase; TGFbeta1 significantly decreased to 37% (P < 0.05) expression of catalase while not significantly affecting expression of both SODs. We conclude that inhibition of spontaneous apoptosis induced by either phenobarbital or clofibrate is accompanied by increases in the endogenous levels of peroxides and by significant induction of catalase gene expression. Furthermore, the lack of effect of both compounds on TGFbeta1-induced apoptosis could be a consequence of the inability of these two compounds to counteract the depressing effect of TGFbeta1 on expression of catalase.   相似文献   
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