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41.
Demographic, clinical and laboratory data were retrospectively collected from records of 146 cases of CT fluoroscopy‐guided chemical lumbar sympathectomy for the palliation of inoperable peripheral vascular disease (PVD) between January 1997 and August 1999. Of these, 16% had claudication, 39% had rest pain and 44% had ischaemic ulcers or gangrene. Seventy‐three percent of elective cases were outpatients. At 3 months, 27 cases were lost to follow up, leaving 119 cases. Within 3 months, improvement, defined as doubling of the walking distance, cessation of rest pain or healing of ulcers, occurred in 30.3% of cases. No change was observed in 45.4% of cases and 24.3% of cases deteriorated. Patients with ulcers or gangrene had significantly poorer results than those without any ischaemic lesions, as only 19% versus 39% of patients improved (P < 0.05). The presence of hypertension, diabetes mellitus, hyperlipidaemia and smoking had no value in predicting clinical outcome (P > 0.05). There were no major complications noted. CT fluoroscopy‐guided chemical lumbar sympathectomy is safe and effective, with a complication rate of less than 1%, and efficacy of at least 30% measured within 3 months. It is a simple and minimally invasive procedure, easily performed on an outpatient basis. CT fluoroscopy‐guided chemical lumbar sympathectomy should be considered for all patients in the early stages of inoperable PVD.  相似文献   
42.
Fong  LY; Lau  KM; Huebner  K; Magee  PN 《Carcinogenesis》1997,18(8):1477-1484
Dietary zinc deficiency in rats induces hyperplasia in the esophagus and increases N-nitrosomethylbenzylamine (NMBA)-induced esophageal tumor incidence. Previous work showed a direct relationship between epithelial cell proliferation and esophageal tumor incidence in rats given multiple doses of NMBA. We investigated the effects of single low doses of NMBA in zinc-deficient rats since a single dose of 5.0 mg/kg was reported to be non-carcinogenic in rats. Zinc-sufficient and deficient rats received a single i.g. dose of NMBA at 0.5 or 2.0 mg/kg. At week 14, tumor incidence was 50% with 0.8 +/- 1.0 tumors/rat, and 80% with 2.2 +/- 1.9 tumors/rat, in deficient groups, D(0.5) and D(2.0), that received the lower and higher dose, respectively. In addition, two small papillomas were found in one out of eight untreated zinc-deficient rats. None of the NMBA-treated or untreated zinc- sufficient rats had any tumors. Esophageal cell proliferation, as determined by proliferating cell nuclear antigen (PCNA) immunohistochemistry, showed that, irrespective of NMBA treatment, deficient esophagi had significant increases in the number of labeled cells, the total number of cells, and the labeling index, as compared with zinc-sufficient ones. Mutations in Ha-ras and p53 genes in esophageal tumors were detected by single strand conformation polymorphism (SSCP) analysis. DNA sequencing of variant conformers revealed a point mutation (GGA-->GAA, codon 12) in Ha-ras in 4/5 (80%) and 5/8 (63%) tumors, from D(0.5) and D(2.0) rats, respectively. Three out of eight tumors from D(2.0) rats exhibited SSCP mobility shifts within p53 exons 5 and 7: two tumors (2/8, 25%) had missense mutations and the third, a silent mutation. Of the two tumors with p53 mutations, one had a double mutation (transition at codon 164, TCA-->TTA; transversion at codon 241, AGT-->TGT), and the other tumor, a transition at codon 172 (AGA-->GGA), with amino acid changes in all cases. In parallel with PCNA expression, elevated p53 expression was associated with hyperplastic and dysplastic regions, as well as with tumors, in deficient esophagi. In short, these data indicate that dietary zinc deficiency, with its associated sustained increased cell proliferation in the esophagus, can drive an otherwise non-tumorigenic dose of NMBA into a highly tumorigenic one.   相似文献   
43.
Recently, the beneficial role of steroids for acute laryngotracheobronchitis has been more clearly defined for both intubated and unintubated patients. However, corticosteroids also improve the clinical signs of airway haemangiomata. Two patients are described who illustrate how this can be a source of diagnostic confusion.  相似文献   
44.
Colorectal hemangioma: radiologic findings   总被引:1,自引:0,他引:1  
The authors correlated radiographs with the clinical and histologic data of 12 patients with colorectal hemangioma. All patients presented with rectal bleeding, which was chronic in seven. Phleboliths were also visible in seven cases, which correlated with chronic bleeding in five. On barium studies, three masses were soft and three produced rigid narrowing. The atypical features of rigid luminal narrowing, which might mimic a carcinoma, and hypovascularity correlated with chronic bleeding or visible phleboliths, which suggest the correct diagnosis of colorectal hemangioma.  相似文献   
45.
Roxatidine acetate, a new H2 receptor antagonist, was compared with ranitidine in the treatment of duodenal ulcers in a double-blind multicentre study. Eighty-four patients with endoscopically proven duodenal ulcer were randomized to receive 150 mg roxatidine acetate or 300 mg ranitidine at bedtime. Repeat endoscopy was performed after 4 weeks (25–33 days) and if the ulcer had not healed, another endoscopy was performed after a further 4 weeks of treatment. Using per protocol analysis 73.6% of ulcers treated with roxatidine healed at 4 weeks compared to 72.2% of ulcers treated with ranitidine (P=NS). The healing rates at 8 weeks were 92% with roxatidine and 83.3% with ranitidine (P=NS). Using equivalence tests, the healing rate of roxatidine was found to be equivalent to that of ranitidine within a 20% region. Roxatidine users took significantly less antacids than ranitidine users (P < 0.05). There were no significant adverse effects due to roxatidine or ranitidine. Roxatidine is a safe effective drug in the treatment of duodenal ulcers with a healing rate comparable to that of ranitidine.  相似文献   
46.
47.
Knowledge of the place and the hazards of intra-uterine transfusion in the severely erythroblastotic foetus, and of the management after delivery, is steadily growing. This procedure was undertaken in an infant who was subsequently delivered at 34 weeks' gestation by emergency Caesarean section following the development of foetal distress. Respiratory distress developed soon after birth and he remained anuric during the 12 days that he survived. An exchange transfusion to ‘wash out’ maternal antibody, and a peritoneal dialysis to combat severe hyperkalaemia were undertaken at the age of 3 hours and 4 days respectively. At post-mortem, the kidneys were found to be nonviable. The early post-natal events were monitored by observations of the electrolytes and the acid-base balance; the fluids used in dialysis and the dialysates were also analysed. These observations are reported and their implications are discussed.  相似文献   
48.
Thallium-201/technetium-99m pertechnetate subtraction scintigraphy of the parathyroid glands was performed in a prospective study of 33 patients who had undergone bilateral neck exploration for elevated serum calcium and serum parathyroid hormone levels. In 31 cases, the Tl-201/Tc-99m subtraction technique yielded an overall sensitivity of 81%, specificity of 99%, and accuracy of 94% for identifying solitary parathyroid adenomas. Tl-201/Tc-99m subtraction scintigraphy correctly identified 73% of parathyroid adenomas weighing less than 499 mg, 79% of those weighing 500-1,499 mg, and 100% of adenomas weighing more than 1,500 mg. In a subgroup of 24 patients with solitary parathyroid adenomas who underwent both scintigraphy and high-resolution sonography, the sensitivity, specificity, and accuracy of both procedures were similar.  相似文献   
49.
Summary.— A further case of peripheral neuropathy has occurred in the course of dapsone therapy. It was predominantly motor in type, but a sensory element was present. It recovered completely after dapsone withdrawal. Electromyography and nerve conduction studies showed the neuropathy to be axonal in type.  相似文献   
50.
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