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51.
OBJECTIVES: The study aimed to review the etiologies of patients who underwent surgery for small bowel obstruction (SBO) and to evaluate the risk factors affecting the early postoperative outcomes. MATERIALS AND METHODS: A case series of 430 patients (252 men) with a mean age of 64.5 years, who underwent 437 operations for SBO, were retrospectively reviewed. RESULTS: Peritoneal adhesions and hernia were the most common causes of SBO, contributing 42.3 and 26.8% of all cases, respectively. Strangulation occurred in 27.7% and caused nonviable bowel in 13.0% of obstructing episodes. Old age (age >/= 70 years), female patient, nonadhesive obstruction, and hernia were the independent significant factors associated with bowel strangulation. The 30-day mortality was 6.5%, and the median postoperative hospital stay was 8 days. Old age, the presence of premorbid pulmonary disease, and malignant obstruction were the independent factors associated with operative mortality. The overall complication rate was 35.5%, and old age was the only significant factor associated with postoperative complications. CONCLUSIONS: Surgery for SBO is still associated with significant mortality and morbidity. As old age is significantly associated with an increased incidence of strangulation, operative mortality, and complications, this group of patients should be managed with extra cautions to avoid unfavorable outcome of surgery.  相似文献   
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53.
BACKGROUND: Dialysis patient mortality remains high, and this high mortality may be due to many factors. In peritoneal dialysis (PD) patients, old age, co-morbid diseases, malnutrition, low residual renal function (RRF) and a high peritoneal transport rate have been shown to influence survival, but the relative importance of these factors may differ between different patient populations. Besides, centre practice patterns may differ between centres and may influence patient survival. In addition, the literature suggests that dialysis patient survival may be better in Asian than in Caucasian patients. METHODS: The influence of centre and patient characteristics on patient survival was investigated in 132 Korean and 106 Swedish incident PD patients, who underwent initial biochemical measurements and assessment of adequacy of dialysis, nutritional status, RRF and peritoneal transport characteristics. RESULTS: At the start of PD, Korean patients had a higher prevalence of diabetes, peritoneal Kt/V(urea), peritoneal creatinine clearance and peritoneal fluid removal, and lower body mass index, RRF and dialysate to plasma creatinine concentration ratio (D/P Cr) compared with Swedish patients. Significantly more patients from Korea were placed on temporary haemodialysis before PD (100 out of 132) when compared with Swedish patients (21 out of 106). During the follow-up, there was a significantly higher rate of transfer to other units in Korea and a significantly higher rate of kidney transplantation in Sweden. On Kaplan-Meier analysis, overall patient survival did not differ and relative risk for death was also not different between the two centres even after adjustment for age, diabetes, cardiovascular disease, RRF and D/P Cr. On Cox proportional hazards multivariate analysis, age, diabetes, RRF and D/P Cr were found to be independent predictors of mortality in the combined cohort of patients. While age, diabetes and D/P Cr were independent predictors of mortality in Korean patients, age and RRF independently predicted mortality in Swedish patients. CONCLUSION: Although there were significant differences in centre and patient characteristics, we were unable to confirm a survival advantage for Korean over Swedish PD patients. The results of this study suggest that the reported difference in survival between Asian and Caucasian dialysis patients may have been due, in part, to differences in centre and patient characteristics rather than to race as such. The genetic influence on patient characteristics remains, however, to be elucidated.  相似文献   
54.
Tissue engineering is an application for gene therapy that is in its infancy. We show that simple liposomal-mediated gene transfer could result in a potentially useful biological effect in the field of wound healing. cDNA encoding the 165 amino acid form of vascular endothelial growth factor complexed to commercially available liposomes was injected into rat skin 1 week before raising a random pattern 3 x 10 cm flap. The flap survival was enhanced by 14 percent, and was accomplished without accessing the arterial inflow of the territory. These results were statistically significant (p<0.002) and reproducible. No adverse effects were seen. Histological analysis of the angiogenesis localized much of the new vessel formation to the area around the hair follicles. Polymerase chain reaction amplification of extracted flap tissue confirmed the presence of the transgene.  相似文献   
55.
A small proportion of thymoma patients without myasthenia gravis (MG) have been observed to develop MG after total removal of the thymoma. However, the underlying cause is not yet known due to the rarity of postoperative MG patients. We report a 39-year-old man in whom MG appeared after surgical removal of a thymoma. Computed tomography and magnetic resonance imaging showed no signs of recurrent or metastatic thymoma. Administration of pyridostigmine bromide resulted in the prompt improvement of myasthenic symptoms. Our observations indicate that postoperative follow-up care with monitoring of possible postoperative MG is necessary after resecting a thymoma.  相似文献   
56.
Vascular 18F-FDG uptake marker represents inflammation in atherosclerotic lesions, but whether inflammation can be reversed by risk-modifying interventions has not, to our knowledge, been demonstrated. In this study, we evaluated the change of vascular 18F-FDG uptake in response to lifestyle intervention on serial PET/CT scans and further assessed how the findings relate to atherogenic risk reduction. METHODS: A total of 60 healthy adults underwent 18F-FDG PET/CT scans and atherogenic risk-factor assessment at baseline and again after 17.1 +/- 8.3 mo of practicing lifestyle modification. The PET/CT images were evaluated for the presence of vascular 18F-FDG lesions, and vessel-to-blood-pool 18F-FDG ratios were measured. Indices from summed ratios of positive lesions were compared and correlated to atherogenic risk factors. RESULTS: At follow-up, significant reductions in diastolic blood pressure (P < 0.05), total cholesterol (P < 0.05), and low-density lipoprotein level (P < 0.05) and an increase in high-density lipoprotein (HDL) level (P < 0.0001) were demonstrated. On the initial PET/CT scan, 50 of 60 subjects showed 1 or more 18F-FDG-positive lesions (5.9 +/- 5.0/subject), leading to a total of 352 vascular sites. On follow-up, 18F-FDG-positive lesions were significantly reduced to 2.1 +/- 2.2 sites per subject (P < 0.0001) and a total of 124 sites (64.8% reduction). Follow-up 18F-FDG-positive rates were significantly reduced for the aorta and iliac arteries. In addition, significant reductions in the whole-body 18F-FDG index from 1.39 +/- 1.23 to 0.53 +/- 0.59 (P < 0.0001) and carotid 18F-FDG index from 0.08 +/- 0.16 to 0.03 +/- 0.06 (P = 0.01) were shown. The whole-body 18F-FDG index correlated with total cholesterol (P < 0.05) and HDL level (P < 0.05), and the magnitude of reduction in the 18F-FDG index closely correlated to the amount of increase in plasma HDL level (P = 0.005). CONCLUSION: Our study demonstrated that vascular 18F-FDG uptake is reversed in response to atherogenic risk reduction by lifestyle intervention and that the magnitude of improvement correlates to increases in plasma HDL levels. Thus, serial 18F-FDG PET/CT may be useful for monitoring improvements in the inflammatory component of atherosclerotic lesions in response to risk modification.  相似文献   
57.
OBJECTIVE: Pamidronate has been studied as a therapeutic drug for various osteopenic diseases. However, avascular osteonecrosis in the jawbone has been recently reported in patients receiving pamidronate. The objective of this study was to examine the effect of pamidronate on bone regeneration in a controlled animal model. MATERIALS AND METHODS: To determine the effect of parmidronate on bone healing in a local bony defect area, a rabbit calvarial bony defect model was used and poly L-lactide-co-glycolide (PLGA) used as a drug carrier material. Four defect groups were made in each rabbit calvaria and the defects were treated as follows: untreated bony defect (group 1), PLGA only (group 2), 2 mg of pamidronate with PLGA (group 3), and 3 mg of pamidronate with PLGA (group 4). Bone healing was evaluated by radiography and histology at 1, 2, 4, 6, and 8 weeks after surgery. RESULTS: In radiographic analysis, radiopacity was lower in pamidronate groups than non-operated rabbit calvarial bone at all observation points (P < .05). In histological analysis, the initial bone formation at 1 week was not different among groups, but it was much lower in the pamidronate groups than in the control or PLGA group after 2 weeks. Newly formed bone at 1 week underwent avascular necrosis after 2 weeks in both pamidronate groups. Avascular necrosis was not observed until 8 weeks in both topically applied pamidronate groups. CONCLUSION: Collectively, pamidronate inhibits bone healing in rabbit calvarial bony defect and it may explain the avascular necrosis of the jaws in patients receiving pamidronate.  相似文献   
58.
59.
Object A radiation dose of 40–50 Gy is able to produce a cure rate of more than 90% in intracranial pure germinoma. However, many attempts have been made to reduce the dose and volume of radiation without compromising the disease control rate because of the toxicity of irradiation. This retrospective study is intended to provide the physician with an appropriate therapeutic strategy. Materials and methods We reviewed a series of 10 recurrent germinomas among 117 germinomas diagnosed histologically or clinically between 1979 and 2002. These patients involved underwent three different treatment modalities; radiation alone (N = 71), chemotherapy alone (N = 9), and combined therapy (N = 37). The 10-year overall and relapse-free survival rates were 97 and 93% in the radiation alone group, 89 and 67% in the chemotherapy alone group, and 92 and 92% in the combined therapy group, respectively. As expected, both radiation therapy and combined therapy were effective in controlling the disease. Tumor recurrence was closely related to the volume of radiation but not to the dose of radiation. If the tumor bed and craniospinal axis were fully covered, the radiation dose might be reduced. Chemotherapy alone showed earlier recurrence and a higher tumor recurrence rate. In the case of combined therapy, chemotherapy was useful in reducing the radiation dose but revealed some toxicity (death of two patients). Conclusions The investigation of a possible further dose reduction seems worthwhile. Radiation therapy alone with a dose of less than 40 Gy should be compared with ongoing chemotherapeutic protocols combined with low-dose irradiation.  相似文献   
60.
Pituitary abscess is a rare and potentially lethal condition. Pituitary abscess in a pregnant woman has not been previously described. A 38-year-old pregnant woman (34 weeks gestation) with a pituitary mass complained of a progressive headache and sudden visual impairment. She was afebrile and had no inflammatory symptoms on admission. On MRI, the preoperative diagnosis was pituitary adenoma with sphenoid sinusitis. She underwent an uncomplicated transsphenoidal procedure for removal of the pituitary mass. The next day, labor commenced and a healthy preterm baby was delivered. Pathologic examination of the intrasellar mass showed polymorphonuclear cells, debris and no tumor cells. The sellar contents were cultured and Streptococcus viridans was grown. To our knowledge this is the first case of pituitary abscess reported during pregnancy. Although the patient was pregnant, the transsphenoidal approach was safe for the mother and the fetus. Surgical drainage and antibiotic therapy are required for the definitive treatment of this condition.  相似文献   
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