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181.
Graded Pneumatic Dilation using Rigiflex Achalasia Dilators in Patients with Primary Esophageal Achalasia 总被引:14,自引:0,他引:14
Shailesh C. Kadakia M.D. F.A.C.P. F.A.C.G. F.C.C.P. Roy K. H. Wong M.D. F.A.C.P. F.A.C.G. 《The American journal of gastroenterology》1993,88(1):34-38
Pneumatic dilation is the initial therapy for primary esophageal achalasia. Recently, polyethylene balloon (Rigiflex) dilators have been used with varying success and complication rate. We performed a total of 47 dilations in 29 consecutive patients with achalasia using the Rigiflex dilators. The 3.0-cm balloon was always used first. If there was no symptomatic response, a 3.5-cm balloon was used after 4–8 wk. If there was still no symptomatic response after 4-8 wk, a 4.0-cm dilator was used. Eighteen (62%) patients were successfully dilated with a 3.0-cm balloon only. Of 11 patients not responding to a 3.0-cm balloon, five were dilated successfully with a 3.5-cm balloon. Of six patients not responding to a 3.5-cm balloon, four were successfully dilated with a 4.0-cm balloon dilator. Two patients eventually required surgery. The overall success with Rigiflex balloon dilator was achieved in 27 of 29 (93%) patients. There were no complications. We conclude that pneumatic dilation for esophageal achalasia performed in a graded fashion starting with Rigiflex 3.0-cm balloon dilator has a high success rate without complications in patients with achalasia. 相似文献
182.
M Ahumada Ayala D Lozano O Lozano J A Rull M Cárdenas V Valles B Wong 《Archivos del Instituto de Cardiología de México》1988,58(1):15-26
Several lines of evidence have clearly established the role of lipoproteins as risk factors for the development of atherosclerosis. Epidemiologic studies from different countries have found that about one third of myocardial infarction survivors under 60 years of age are hyperlipidemic. The acute stress reaction occurring in the first hours following an acute myocardial infarction causes distinct changes in the patient's metabolic profile, these changes include a significant reduction of total cholesterol and cholesterol associated with low density lipoproteins and a usually mild elevation of blood glucose. With the purpose of establishing the prevalence and severity of lipoprotein disorders found in myocardial infarction survivors living in Mexico city we conducted a prospective study of 106 consecutive admissions to the coronary care unit at the National Institute of Cardiology with the fully proven diagnosis of acute myocardial infarction, we included only patients younger than 60 years of age that could be sampled within the first 72 hours of the appearance of typical symptoms, at this time the coronary risk factor profile was assessed and blood samples were drawn (acute sample). After three months of the diagnosis we sampled 81 of the original 106 patients (chronic sample). The comparison of these 81 patients showed remarkable differences in the lipid values obtained on each sample. The mean value for total cholesterol in the acute sample was 225 mg/dl whereas the corresponding value for the chronic sample was 240.5 mg/dl (p less than 0.005). This difference was also highly significant for the low density fraction. On the basis of the chronic sample analysis we estimated a prevalence of hyperlipoproteinemia of 35.8%. (II: 18.5%, III: 2.5%, IV: 14.8%), an additional subgroup of 10 patients (12.3%) had the hypo-HDL phenotype raising the number of subjects at risk for atherosclerosis to as high as 48.1% considering only the lipoproteins. The prevalence figures for the rest of the risk factors were as follows: 70.3% for tobacco smoking, 35.8% for Systemic Arterial Hypertension, 33.4% for Obesity and 30.8% for Diabetes Mellitus. Among the group of 81 patients, 17 were known diabetics, eight additional cases of Diabetes Mellitus were diagnosed at the chronic phase (two with fasting hyperglycemia and six with diagnostic oral glucose tolerance tests). The "acute plase" glycemia for these eight subjects was significantly higher (mean: 98.4 mg/dl) than the corresponding value for the non diabetic patients (mean: 83.4 mg/dl p less than 0.002), the seventeen known diabetics had a mean glycemia of 150.6 mg/dl in the acute sample.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
183.
184.
Runners' diarrhea. Different patterns and associated factors. 总被引:6,自引:0,他引:6
One hundred and nine distance runners participated in a questionnaire survey of bowel function related to running. Thirteen (12%) had had fecal incontinence while running. Sixty-eight (62%) had stopped to have a bowel movement while training. Forty-seven (43%) had "nervous" diarrhea before competition and 13 (12%) had stopped during competition for a bowel movement. Fifty-one (47%) had experienced diarrhea after racing or hard runs and 17 (16%) had seen blood in their stool in the same situations. Runners who had nervous diarrhea before competition were more likely to have symptoms of milk intolerance and irregular bowel function when not exercising, and runners who had symptoms of the irritable bowel syndrome often had to stop for a bowel movement during training. Runners with diarrhea after racing or hard runs frequently experienced severe abdominal cramps, nausea and vomiting, and occasionally, rectal bleeding at the same time. Any form of "runners' diarrhea" was unrelated to age, previous intestinal infection or food poisoning, food allergies, or dietary fiber. 相似文献
185.
At least two mutant alleles of ornithine delta-aminotransferase cause gyrate atrophy of the choroid and retina in Finns. 总被引:11,自引:1,他引:10
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G A Mitchell L C Brody I Sipila J E Looney C Wong J F Engelhardt A S Patel G Steel C Obie M Kaiser-Kupfer et al. 《Proceedings of the National Academy of Sciences of the United States of America》1989,86(1):197-201
Gyrate atrophy of the choroid and retina (GA) is an inherited chorioretinal degeneration caused by deficiency of ornithine delta-aminotransferase (OAT; L-ornithine: 2-oxo-acid aminotransferase; EC 2.6.1.13). GA is one of the "Finnish genetic diseases," a group of several rare monogenic disorders that occur with increased frequency in the Finnish population. Using a combination of RNase A protection, genomic cloning, and polymerase chain reaction amplification of genomic DNA, we found one of two missense mutant OAT alleles to be present in each of 16 Finnish GA pedigrees. The first mutation R180T, in which arginine-180 is replaced by threonine, was present in homozygous form in patients from two pedigrees. The second mutation L402P, in which leucine-402 is replaced by proline, was present in homozygous form in patients from 14 pedigrees. Neither mutation was present in 19 Finnish controls. L402P was not present in 18 non-Finnish GA patients but R180T was found in an American GA patient. We constructed full-length mutant cDNAs by amplifying patient cDNA with the polymerase chain reaction and cloning a restriction fragment containing the mutation into an otherwise normal human OAT cDNA. These mutant cDNAs were then expressed in CHO-K1 cells, which lack endogenous OAT. Both R180T and L402P inactivate OAT. These results show molecular heterogeneity in GA alleles even in the Finnish population. 相似文献
186.
Burnout is a syndrome of emotional exhaustion, depersonalization, and reduced personal accomplishment that can occur among individuals who do "people work" of some kind. Health care providers, including dentists, are at high risk for burnout because their occupation often requires intense interaction with fearful, demanding patients on a daily basis. The purpose of this study was to assess the prevalence of burnout among Texas dentists using a standardized measurement device, the Maslach Burnout Inventory (MBI). Dentists attending the 1989 Texas Dental Association Annual Session were surveyed using the MBI. The respondents' results were analyzed and compared to each other as well as to the norms of medicine and to society (human service workers nationwide). Among the Texas sample, male dentists scored significantly higher for emotional exhaustion and depersonalization than did female dentists. When compared to the norms of medical workers, Texas dentists scored higher burnout in the depersonalization subscale, but lower burnout for personal accomplishment. The Texas sample again scored lower for burnout in the personal accomplishment subscale when compared to societal norms. At no time did the Texas sample fall into the high range of experienced burnout as defined by the survey instrument. Texas dentists did not appear "burned out" as a group and actually demonstrated an increased sense of personal accomplishment in their profession. 相似文献
187.
Axotomy-induced changes in the expression of a type III neuronal intermediate filament gene 总被引:7,自引:0,他引:7
The effect of axotomy on the expression of the 57 kDa neuronal intermediate filament (IF) protein in adult rat dorsal root ganglion (DRG) neurons was examined. This IF protein is known to have an exclusively neuronal localization but is considerably more limited in its distribution in the nervous system than the neurofilament (NF) triplet proteins. The 57 kDa neuronal IF protein is similar (and perhaps identical) to the protein "peripherin" and is known to be the product of a Type III IF gene. Since the down-regulated expression of NF proteins (products of type IV IF genes) has been well established, it was of interest to determine whether the novel 57 kDa IF protein was regulated in a similar or different manner from that of the NFs in axotomized neurons. In vitro pulse-labeling of DRGs with 35S-methionine: cysteine followed by 2-dimensional gel electrophoresis/fluorography revealed that the synthesis of the 57 kDa neuronal IF protein was increased 2 weeks after sciatic nerve crush. Immunocytochemical studies using a polyclonal antibody to the 57 kDa neuronal IF protein showed that the immunodetectable levels of this protein increased in DRG neurons after peripheral axotomy. In the normal DRG, staining was localized almost exclusively to small-sized neurons. At 2 weeks after axotomy, however, large- and medium-sized neurons also became immunoreactive; in addition, the overall level of staining in the DRG was greater than normal. Quantitative analysis of in situ hybridizations of DRG neurons with a 35S-labeled cDNA probe specific for the 57 kDa neuronal IF protein revealed a significant increase in the level of 57 kDa IF mRNA in the large-sized (greater than 1000 microns2) neurons 2 weeks after axotomy; the level of 57 kDa IF mRNA in the small neurons was not different from normal at that time. Finally, using a newly developed paradigm for examining the composition of regenerating axons by axonal transport, we determined that significant amounts of the 57 kDa neuronal IF protein were conveyed into the regrowing axonal sprouts of DRG neurons. When DRG neurons were conditioned by a previous axotomy (a crush axotomy of the distal sciatic nerve 2 weeks earlier) and then stimulated to regenerate axons by a second crush axotomy located very close to the DRG, the regenerating sprouts incorporated and conveyed significantly more 57 kDa IF protein by slow axonal transport than did those elaborated by unprimed DRG neurons.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
188.
E K Lancaster R A Evans S Kos E Hills C R Dunstan S Y Wong 《Journal of bone and mineral research》1989,4(4):507-514
Bone mineral content (BMC) was measured in the os calcis of 232 normal subjects aged 17-82 years. The mean reproducibility (coefficient of variation) of the measurement was 1.8%. Substantial bone loss occurred between the ages of 20 and 50 years, and in females the menopause was associated with additional bone loss. There was no significant difference in the rate of bone loss in females and males, but the mean BMC was greater at all ages in males than in females. We also compared os calcis BMC with spinal bone mineral density (BMD), measured by quantitative computed tomographic (CT) scanning, in 85 subjects: 33 were normal controls, 19 had osteoporosis defined by the presence of one or more pathological fractures, and in the remainder the CT examination was performed at the patient's request. Os calcis BMC correlated with spinal BMD in both females (r = 0.69, p less than 0.001) and males (r = 0.84, p less than 0.001). However, the os calcis BMC did not reliably predict spine values around the CT "fracture threshold" of 90-100 mg/cm3 and did not correlate with osteoporotic fracture as well as did spinal BMD. It is concluded that measurement of the os calcis BMC is of limited clinical usefulness for the early diagnosis of osteoporosis. 相似文献
189.
This is a retrospective study of the outcome of surgical procedures in patients who were Jehovah's Witnesses. Over a 75-month period, 58 Jehovah's Witness patients had 78 surgical procedures at the Vancouver General Hospital. Three patients had preexisting anaemia of less than 100 g.L-1 haemoglobin. Postoperative haemoglobin concentration decreased below 50 g.L-1 in three patients. One patient had a postoperative haemoglobin of 34 g.L-1 (haematocrit 10.1 per cent) and survived. One patient died from uncontrollable postoperative haemorrhage. Perioperative morbidity was not uncommon, including significant hypotension (eight cases), cardiac arrhythmias (six), myocardial ischaemia (three), excessive bleeding (four), postoperative nausea or syncope (four), and wound or urinary tract infection (four). 相似文献
190.
A prospective randomised clinical trial was conducted to examine the efficacy of 2 weeks pre-operative parenteral nutrition (PPN) for the prevention of complications following surgery for oesophageal cancer. Forty patients were studied, the diet of twenty being supplemented by pre-operative parenteral nutrition. There were no significant differences in age, nutritional status, tumour staging and histology between the two groups of patients. The use of PPN resulted in a significant gain in body weight and nitrogen but failed to produce an overall reduction in post-operative morbidity and mortality rates. However patients receiving PPN exhibited two types of changes in serum albumin levels. Those with a fall in serum albumin levels associated with an increase in body weight (indicating an expansion of extracellular volume) had a significantly higher incidence of post-operative pulmonary complications than the group exhibiting a rise in serum albumin levels concomitant with increase in body weight. These data suggested that two weeks PPN might not be adequate in certain patients and a longer period of PPN is required. They also show no clinical benefit from the routine use of pre-operative parenteral nutrition in all patients, but do not exclude benefit in selected groups. 相似文献