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11.
BACKGROUND: Pathological changes in vein grafts begin immediately after arterial circulation is applied to the grafts. Chemical mediator stimulation and mechanical strain induce neointimal hyperplasia and medial thickening of the vein grafts, resulting in their failure. We investigated the inhibitory effect of locally applied cilostazol, an inhibitor of cyclic adenosine monophosphate phosphodiesterase III, on neointimal hyperplasia and medial thickening of the grafts. METHODS AND RESULTS: We established a distal anastomotic stricture model of femoral vein-abdominal aorta interposition grafting in rats. In this model, neointimal hyperplasia was observed not only at the distal anastomotic sites, but also in the graft body at postoperative day 14 and was markedly progressed at day 28. A strong expression of tenascin-C was found in the media and neointima of the graft body. In the grafts around which cilostazol was administered locally using Pluronic gel, neointimal hyperplasia was significantly suppressed compared with control grafts treated with the gel alone, with the mean neointimal cross-sectional area reduced by 87.1% for the graft body and by 78.9% for the distal anastomotic sites and mean medial cross-sectional area of the graft body reduced by 54.2% at day 28 versus the control. Cilostazol treatment decreased cell proliferation and the number of tenascin-C-producing cells seen by in situ hybridization, but the expression of tenascin-C protein was not suppressed. CONCLUSION: We concluded that a single perivascular application of cilostazol inhibits neointimal hyperplasia and medial thickening of vein grafts in a rat model.  相似文献   
12.
Fifty-four patients with 65 superficial malignant lesions were treated by local hyperthermia combined with radiation therapy at the National Cancer Center Hospital, Tokyo. Hyperthermia was delivered with an Aloka Model HMS-020 (2450 MHz) or with a horn-type applicator of BSD-1000 (80-90 MHz). Relatively small tumours, those less than 4 cm in thickness, were treated by using 2450 MHz while 80-90 MHz delivered through the horn-type applicator was used for tumours exceeding 5 cm in thickness. The radiation dose was 4 Gy twice a week or 2 Gy five times a week, the total dose being 40-60 Gy. A total of six to 10 hyperthermia treatments ranging from 40 to 60 min each, with the tumour heated to more than 42.5 degrees C, were given twice a week within 1 h following radiation therapy. Complete response was achieved in 16 of the 30 patients (55 per cent) treated with the 2450 MHz microwave, and partial response in seven others (23 per cent). Tumours treated with the BSD-1000 achieved complete response in 10 out of 33 patients (30 per cent) and partial response in nine others (27 per cent). In five out of nine patients classified as partial responders, however, complete disappearance of tumour cells was noted by post-treatment histological examination. Complete plus partial response rates were thus essentially the same with the Aloka HMS-020 and the BSD-1000, though the rate of complete response was apparently higher with the Aloka unit, probably because it was used on smaller tumours.  相似文献   
13.
Intravesical instillation of anti-cancer drugs for superficial urinary bladder cancer is generally carried out with the aim of prophylaxis against recurrence and chemotherapy against tumor. But since sensitivity of tumor cells to each anti-cancer drug differs individually, the anti-cancer drug to be used should also be decided individually. We selected a new sensitivity test, ATP-sensitivity-assay, which measures intracellular adenosine triphosphate (ATP) volume by Luciferin-Luciferase reaction, for the decision of the anti-cancer drug. In this paper, we evaluated the direct anti-tumor activity of the drugs that were decided by ATP-sensitivity-assay of intravesical chemotherapy. Six drugs, that are Doxorubicin (ADM), Mitomycin C (MMC), Pirarubicin (THP-ADM), Cytarabine (Ara-C), Bleomycin (BLM) and Cisplatin (CDDP) were tested in this research and size of tumors of six patients reduced to 34-93% after 6 times' installation. A woman got cystitis induced by ADM after 3 times' instillation but instillation was completed. ATP-sensitivity-assay is useful for deciding the anti-cancer drugs for intravesical chemotherapy and prophylaxis for superficial bladder cancer.  相似文献   
14.
Among diseases due to cerebral parasitism, that caused by Sparganum mansoni, the larva of Spirometra mansoni, is very rare. We have encountered two such cases. A computed tomography scan in both revealed a nodular high density contrast enhanced area against an extensive low density background area. Neither calcification nor cyst formation was recognized. These computed tomography scan findings were thought to be characteristic for cerebral sparganosis mansoni and were difficult to differentiate from those of a cerebral tumor. In both cases, definitive diagnosis was achieved by identification of the worm after excision of the lesion. The best treatment for cerebral sparganosis mansoni is surgical excision of the lesion, and in the two cases presented the postoperative outcome was good.  相似文献   
15.
The tumor vessels of a primary meningeal malignant melanoma were studied by electron microscopy. There were numerous endothelial fenestrae and basal lamina abnormalities in the intrinsic tumor capillaries. They resembled the tumor vessels found in nonglial tumors, but were distinctly different from those seen in glial tumors with nonfenestrated capillaries. These findings were anticipated because leptomeninges have fenestrated capillaries.  相似文献   
16.
A 74-yr-old man was scheduled for the biopsy of prostatic tumor under spinal anesthesia. Preoperative serologic test for syphilis was highly positive. Spinal anesthesia was performed in the sitting position, and 2 ml of hyperbaric Neo-percamine S (a mixture of 0.24% dibucaine and 0.12% T-caine) was administered uneventfully with the onset of warm sensation on the perineal region. Ten minutes later, however, he began to complain of severe lightning sensation on the feet. After giving pentazocine intravenously, the short cystoscopic procedure was completed. As a cause of severe pain, an erroneous anesthetic solution or direct neuronal injury had been excluded because of rapid and complete recovery after anesthesia. Two weeks later, he was scheduled for TUR-P. He again complained of severe lightning pain after the successful spinal anesthesia with the same anesthetic solution. Because the pain was not relieved by analgesics, he was then anesthetized with enflurane and N2O in oxygen, and there were no neurological complications after anesthesia. Several cases of severe pain during spinal anesthesia have been reported in patients with tabes dorsalis. Although the patient lacks clear symptoms of neurosyphilis, positive serologic examination for syphilis without any other possible causes suggests altered sensitivity of the spinal cord to anesthetic solutions.  相似文献   
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Effects of vancomycin and ofloxacin on rabbit ERG in vivo   总被引:1,自引:0,他引:1  
The retinal toxicity of vancomycin and ofloxacin was studied by electroretinogram (ERG) before and after intravitreal injection in rabbits. Vancomycin is known to be effective on methicillin-resistant Staphylococcus aureus. A dose of 1mg vancomycin caused no ERG change for at least eight weeks after injection. The feature that ERG became non-recordable during one to four weeks after an intravitreal injection of 10mg vancomycin, with recovery of only the c-wave was conspicuous. A dose of 200 micrograms ofloxacin did not cause deterioration of the b-wave, the c-wave or the oscillatory potentials throughout the follow-up period up to eight weeks. Judging from the susceptibility of each ERG component to antimicrobials and taking into account the difference of vitreous volume between rabbits and humans, clinical doses of intravitreal single-shot injection should be less than 1mg for vancomycin and 200 micrograms for ofloxacin.  相似文献   
20.
A 38-year-old female presented with a lower abdominal mass. During the operation the mass was found to be retroperitoneal and was excised. Gross examination revealed a mucin-containing cystic lesion with a mural nodule. On microscopic examination, the cystic areas were lined by an invasive mucinous adenocarcinoma and the nodule was composed of an anaplastic sarcomatoid tumor that was immunoreactive for cytokeratin. This present case is the 21st example of a retroperitoneal primary mucinous cystadenocarcinoma and the fourth with a mural nodule. Three of four cases with a mural nodule, including our case, had a rapidly fatal outcome.  相似文献   
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