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81.
PURPOSE: To examine the efficacy of surgical removal of subfoveal hard exudates during surgery in diabetic maculopathy. PATIENTS AND METHODS: This study was done on 60 patients (66 eyes) that all underwent surgical removal of subfoveal hard exudates under the same surgeon. Thirty-two men (37 eyes) and 28 women (29 eyes) were included in this study. The average age of the patients was 60 years (range, 30-77 years). The average follow-up period was 21 months (range, 12-48 months). All eyes were classified into 3 groups: 13 postoperative massive type eyes, 31 massive type eyes, and 22 scatter type eyes. We evaluated the visual results of these types. RESULTS: Preoperative and postoperative mean visual acuity was as follows: postoperative massive type 0.11, 0.22, massive type 0.12, 0.29, and scatter type 0.19, 0.33. Postoperatively visual acuity improved significantly in all types. There were no subfoveal hard exudates postoperatively in any eyes. CONCLUSION: Surgical removal of massive subfoveal hard exudates is effective, but its effects on vision are limited. Surgical removal of deposited subfoveal hard exudates may prevent massive subfoveal hard exudates postoperatively and improve visual prognosis.  相似文献   
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Titanium alloy (Ti) commonly is used for long-term blood pumps as a conventional blood contacting material. Thrombus formation in the pump, however, is still a critical problem. Once thrombin is generated on the Ti surface, it activates platelets and the coagulation cascade, leading to thrombus formation. It would be expected that an inhibition of thrombin generation on a blood-contacting surface would prevent thrombus formation. In this study, the titania gel (Ti-gel) on the surface of Ti was formed with chemical modification. The surface structure and its effects on the coagulation cascade were evaluated. Scanning electron microscopic study revealed numerous cracks on the dried surface of Ti-gel, indicating a water-enriched layer. Blood coagulation on the Ti-gel was less than that on the Ti. Generated thrombin on the Ti-gel was less than that on the Ti in both the extrinsic and intrinsic pathways. There was no statistical difference of thrombin degradation. These results suggest that coagulation cascade on the Ti surface was inhibited by the Ti-gel formation. The Ti-gel may have better antithrombogenic characteristics for blood pumps because of its antiblood-coagulation effects.  相似文献   
83.
A previous report demonstrated that AP-2alpha favors the survival of ovarian cancer patients by clinical findings. However, the functional roles of AP-2alpha in human ovarian cancers have not been determined. To clarify the roles, we overexpressed AP-2alpha in SKOV3 human ovarian cancer cells, which originally possess little AP-2alpha. AP-2alpha overexpression changed cell morphology from spindle to epithelioid type and suppressed cell proliferation and invasion, which would be partially correlated with decreased phosphorylation levels of the erbB2, Akt and ERK pathways, increased E-cadherin and reduced pro-matrix metalloproteinase-2 levels. Moreover, nude mice intraperitoneally injected with AP-2alpha-overexpressing cells survived longer than those with neo-transfected cells. The present data represent the first direct evidence that AP-2alpha plays a tumor suppressive role in ovarian cancer.  相似文献   
84.
Percutaneous radiofrequency ablation (RFA) is able to destroy hepatocellular carcinoma (HCC) in a few sessions without major complications. We have previously shown that not only the combined use of percutaneous ethanol injection and RFA (PEI-RFA) but also injection of mixture of ethanol and lipiodol (PELIT) was useful for the treatment of HCC. In the present study, we further developed the combined use of PELIT and RFA through percutaneous or laparoscopic approach (PELI-RFA or LELI-RFA) and evaluated its usefulness. Nineteen nodules in 18 cases were treated with PELI-RFA or LELI-RFA. In the cases treated with LELI-RFA, no bleeding and no spilling milky fluid containing tumor cells were observed from the surface of ablated tumors. In the cases sufficiently treated with PELI-RFA or LELI-RFA, the mixture of ethanol and lipiodol was accumulated in the entire region of the tumor and low-density area was observed around the lipiodol deposit by computed tomography (CT). These delineations of coagulated area were helpful to evaluate the precise area of safety margin around the tumor treated with PELI-RFA or LELI-RFA. Furthermore, the total volume of coagulated necrosis significantly and positively correlated with the product of energy requirement for ablation and the volume of ethanol injected by PELI-RFA or LELI-RFA. Among the cases treated with PELI-RFA or LELI-RFA, local recurrence emerged only in one case in whom enough safety margin could not be achieved by PELI-RFA. Therefore, it is critical to evaluate whether enough safety margin could be obtained with RFA therapy, and PELI-RFA and LELI-RFA are helpful in visualizing the safety margin area.  相似文献   
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The epidemiology and treatment outcomes for Diamond-Blackfan anemia (DBA) were surveyed in a cohort of 54 children (M/F = 26:28) registered in Japan from 1988 to 1998. The annual incidence was 4.02 cases per million births, the median age at diagnosis was 60 days, and 59% of the cases presented by 3 months of age. Three patients had a familial occurrence. All patients received prednisolone (PSL), and cyclosporin A (CsA) was added to the therapy in 17 patients. Forty-seven patients received transfusions, and 13 underwent hematopoietic stem cell transplantation (HSCT). The cumulative probabilities of a medication-free or a transfusion-free state prior to HSCT were 36% and 69%, respectively, at more than 5 years after diagnosis. Thirteen patients were weaned from PSL therapy without HSCT, and CsA was not associated with weaning from therapy. Transfusion and medication were stopped at 249 days and 933 days after diagnosis in 34 and 13 patients, respectively, who achieved a state of independence. No initial findings predicted the treatment dependence. More than 20% of patients experienced sustained hemosiderosis and/or adverse effects of PSL. The ages and reticulocyte counts at diagnosis of the patients who underwent HSCT were lower than in the patients who did not. HSCT led to the highest success (85%) of all previous reports, even though 5 alternative donors were included in our study. Two cord blood transplants from unrelated donors failed. These findings suggest the need for developing an integral treatment strategy including selective HSCT for refractory DBA.  相似文献   
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Background

The purpose of this study was to examine the long-term outcome and the prognostic predictors related to the development of complications associated with acute type B aortic dissection.

Methods

Seventy-six medically treated patients with acute type B aortic dissection were examined between 1990 and 2001. The events associated with aortic dissection included dissection-related death, rupture, visceral ischemia, lower limb ischemia, an increase in the maximum aortic diameter greater than 50 mm, and a mean enlargement rate of greater than 5 mm per year.

Results

Among the 76 patients 10 (13%) underwent chronic phase surgery and 25 (33%) presented with an event. A statistically significant difference was observed between patients with and without events with regard to atherosclerotic factors, blood flow status in the false lumen, maximum aortic diameter upon admission, mean aortic enlargement rate, and blood pressure control during follow-up. Of these factors a patent false-lumen and a maximum aortic diameter greater than 40 mm upon admission were the most strongly associated factors with regard to the development of events. Patients with a patent false-lumen and a maximum aortic diameter greater than 40 mm upon admission were determined to exhibit significantly higher event rates than other patients.

Conclusions

In determining the appropriate therapeutic approach for acute type B aortic dissection, it is important to pay careful attention to the predictors of a patent false-lumen and a maximum aortic diameter greater than 40 mm at onset to improve the long-term outcome.  相似文献   
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