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21.
In our previous study, we examined reactive oxygen species (ROS) formation in T lymphocytes following 5 Gy irradiation. We found that ROS formation occurred immediately after irradiation, continued for several hours, and resulted in oxidative DNA damage. Therefore, the origin of the hyper-radiosensitivity of T lymphocytes seemed to be the high production of ROS in the mitochondrial DNA following irradiation. In the succeeding study, we examined radiation-induced ROS formation, oxidative DNA damage, early apoptotic changes, and mitochondrial membrane dysfunction in the human osteosarcoma cell line HS-Os-1. We found that ROS formation and oxidative DNA damage were actually scarcely seen after irradiation of up to 30 Gy in these cells, that mitochondrial membrane potential was preserved, and that apoptotic changes were not demonstrated despite the relatively high-dose irradiation of 30 Gy. In the present study, we examined the immunocytochemical characteristics of the apoptotic-resistance of the HS-Os-1 cell line against irradiation in order to clarify its possible implications regarding radiosensitivity. The results showed that these cells lack P53 and Bax protein expression, and strong peroxidase activity was confirmed in the nuclei of the cells. Moreover, SODII (manganese superoxide dismutase II) protein expression was gradually increased in spite of irradiation of up to 30 Gy. Therefore, it is concluded that HS-Os-1 cells are originally apoptotic-resistant and that the cells possess a strong ability to scavenge for free radicals. To convert these cells to a state of apoptotic-susceptibility, a powerful oxidant such as hydrogen peroxide might exert such an effect in terms of the production of hydroxyl radicals in lysosomes in the cells as shown in our previous studies. The origin of the radioresistance of the human osteosarcoma cell line HS-Os-1 is considered to to be low degree of ROS formation following irradiation, reflecting the strong scavenging ability of these cells for free radicals including hydroxyl radicals.  相似文献   
22.
Homologous and heterologous combinations of enzyme conjugate and antibody in steroid enzyme immunoassay (EIA) influences unlabeled steroid recognition by antibody that affects sensitivity of the assay. To develop corticosterone enzyme linked immunosorbent assay (ELISA), antibodies were generated against corticosterone-3-carboxymethyloxime-bovine serum albumin (corticosterone-3-CMO-BSA) and corticosterone-21-hemisuccinate-bovine serum albumin (corticosterone-21-HS-BSA). Four horseradish peroxidase (HRP) enzyme conjugates were prepared using two corticosterone derivatives (corticosterone-3-CMO and corticosterone-21-HS) and two cortisol derivatives (Cortisol-3-CMO and Cortisol-21-HS). Eight combinations of homologous and heterologous assays were evaluated. The use of antigen heterologous combination resulted in development of assay. The developed assay is simple, direct, and convenient to use, as it permits the direct addition of the serum sample in to the assay, and it requires only 1.5 hours to complete.  相似文献   
23.
24.
PURPOSE: To quantify pure arterial blood perfusion of liver tumor and parenchyma by using CT perfusion during selective hepatic arteriography. METHODS: A total of 44 patients underwent liver CT perfusion study by injection of contrast medium via the hepatic artery. CT-perfusion parameters including arterial blood flow, arterial blood volume, and arterial mean transit time in the liver parenchyma and liver tumor were calculated using the deconvolution method. The CT-perfusion parameters and vascularity of the tumor were compared. RESULTS: A complete analysis could be performed in 36 of the 44 patients. For liver tumor and liver parenchyma, respectively, arterial blood flow was 184.6 +/- 132.7 and 41.0 +/- 27.0 ml/min/ 100 g, arterial blood volume was 19.4 +/- 14.6 and 4.8 +/- 4.2 ml/100 g, and arterial mean transit time was 8.9 +/- 4.2 and 10.2 +/- 5.3 sec. Arterial blood flow and arterial blood volume correlated significantly with the vascularity of the tumor; however no correlation was detected between arterial mean transit time and the vascularity of the tumor. CONCLUSION: This technique could be used to quantify pure hepatic arterial blood perfusion.  相似文献   
25.
PURPOSE: The usefulness of metallic stent placement and post-balloon dilatation was investigated for patients with residual stenosis after conventional percutaneous transluminal balloon angioplasty (balloon PTA) of dialysis shunt vessels. MATERIALS AND METHODS: Among 92 patients who had received balloon PTA for dialysis shunt vessels, seven patients who showed a residual waist on the balloon even under maximum inflation were enrolled in this study. In these patients with residual stenosis after balloon PTA, we inserted a stent in the residual stenosis, and post-balloon dilatation was immediately applied using the same balloon catheter. RESULTS: After balloon PTA, the average percent diameter stenosis declined to 45.5 +/- 7.30%, and the stenosis was further improved to an average of 19.3 +/- 7.09% after the placement of a stent and the additional balloon PTA. The average percent diameter dilatation of the balloon before the placement of a stent was 65.8 +/- 12.7%, while the average dilatation increased to 84.1 +/- 8.96% after the placement of a stent. Dialysis became possible immediately after the procedure in all cases. CONCLUSION: Metallic stent placement and post-balloon dilatation was effective for patients with residual stenosis after conventional balloon PTA of dialysis shunt vessels.  相似文献   
26.
During various knee operations, the changes caused by the surgical invasion to the infrapatellar fat pad (IPF) is still unknown. If any changes exist, it will have great influence especially on growing generations. Eighty-four Japanese white rabbits (6-month-old) were divided into three groups: the resection group involving resection of the IPF, the graft group involving resection and reimplantation of the IPF, and the no-surgery group. All these surgical procedures were done in right knees. In all left knees, only arthrotomy was performed, serving as the sham side. After 3, 6, 12, and 24 weeks of the operation, the rabbits were killed. Lengths of the patellar tendon and patellar were measured in lateral X-ray. In order to eliminate individual differences in the patellar height, we defined a new index as percent patellar height (PPH) which indicated the percentage of the patellar height of surgery side compared with that of the sham side. The PPH was 90.6% (3 weeks), 83.0% (6 weeks), 73.6% (12 weeks), and 74.7% (24 weeks) in the resection group, while it was 88.4% (6 weeks), and 88.9% (24 weeks) in the graft group. Postsurgical scar tissue formation occurring where the IPF was removed prevented the normal growth of the patellar tendon. Reimplantation of the IPF lessened the adhesion of the patellar tendon to the surrounding tissue, and better growth of the tendon. These results showed that preservation of the IPF in young individuals could be crucial for the normal growth of the patellar tendon, and critical as well for the prevention of the degeneration of the articular surface.  相似文献   
27.
Kiyonori Kariya  MD    Takuo Tsuji  MD  PhD    Robert A. Schwartz  MD  MPH 《Dermatologic surgery》2004,30(S2):341-344
Background. An effective chemotherapy for advanced extramammary Paget's disease has not yet been established. Recently, a low dose 5-fluorouracil/cisplatin (FP) regimen has been reported to be effective for adenocarcinoma, including gastric and colon carcinoma. However, this chemotherapeutic option has not been evaluated as to its effectiveness for extramammary Paget's disease.
Objective. We evaluated chemotherapy in a patient with advanced extramammary Paget's disease of the male genitalia unassociated with an underlying malignancy.
Methods. In order to treat a patient with extramammary Paget's disease who had multiple metastases, 500 mg/day of 5-fluorouracil (7 days per week) and 5 mg/day of cisplatin (5 days per week) were administrated intravenously for 24 hours and 1 hour, respectively. This protocol was continued for 6 weeks.
Results. A partial response was observed in both primary disease and metastatic disease. The primary tumor resolved almost entirely, leaving only a scar. Computed tomography scan revealed liver metastases that appeared to change into necrotic tissue; the metastases in lymph nodes and adrenal glands were markedly decreased and hardly detectable. In addition, the carcinoembryonic antigen level, a useful tumor marker for extramammary Paget's disease, decreased remarkably. It is suggested that this patient's survival period could have been prolonged. Serious side effects were not observed during this treatment.
Conclusion. In one patient with extramammary Paget's disease and multiple metastases, low-dose FP therapy appeared to be beneficial. This regimen may be effective for extramammary Paget's disease with systemic nodular metastasis as an adjuvant therapy combined with surgery.  相似文献   
28.
Transcanal endoscopic ear surgery (TEES) will become a very useful therapeutic option. A perilymphatic fistula (PLF) is defined as sudden sensorineural hearing loss and/or vertigo caused by leakage of the perilymph through a fistula from the oval window and/or round window. We report a case of PLF after electric acoustic stimulation (EAS), a kind of cochlear implant, successfully treated by TEES. A 38-year-old man presented to our hospital with vertigo and hearing loss (HL). His vertigo was induced by Valsalva maneuvers. Eight months ago, he underwent EAS for his right ear for congenital sensorineural HL. Although he maintained his hearing level after EAS, his pure tone audiogram this time showed deterioration of hearing at low frequencies in his right ear. A diagnosis of right PLF was made. After confirming the non-effectiveness of oral prednisolone treatment, PLF repair surgery to patch the oval and round windows by TEES was performed. His vertigo did not recur after the surgery. To the best of our knowledge, this is the first report of PLF repair surgery by TEES without a microscope. The wide-field view of the middle ear by TEES was useful to prevent electrode damage in a PLF patient with a cochlear implant.  相似文献   
29.
An elderly patient with breast cancer received toremifene monotherapy for one year, and about 60% tumor remission rate was obtained. Since viability of the residual tumor was suspected on ultrasonography (US), computed tomography (CT), and magnetic resonance imaging (MRI), lumpectomy was performed under local anesthesia. The histopathological diagnosis was ductal carcinoma in situ (DCIS). The patient did not undergo axillary lymph node dissection or systemic chemotherapy. The patient is alive without disease under postoperative radiotherapy and toremifene treatment. Toremifene monotherapy and/or preoperative adjuvant therapy with toremifene alone may be useful methods for elderly patients with breast cancer considering the patients' quality of life.  相似文献   
30.
A 4-kb mRNA for colony-stimulating factor 1 (CSF-1) was detected in normal human placenta at term by Northern blot analysis. In-situ hybridization revealed that the mRNA for CSF-1 was localized in the mesenchymal cells of the chorionic villous stroma, but not in the trophoblasts or capillary epithelial cells. Because there are significant numbers of tissue macrophages (Hofbauer cells) in the placental stroma and because the receptor for CSF-1 (the c-fms proto-oncogene product) is known to be expressed by trophoblasts, our results suggest that CSF-1 produced by placental stromal cells may act as a growth and survival factor for human placental macrophages and trophoblasts.  相似文献   
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