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91.
The effectiveness of various oxygen carrying treatments in sensitizing subpopulations of the FSallC fibrosarcoma to low doses of radiation was assessed, and compared with survivals obtained with the same cells after in vivo irradiation under normally oxygenated or hypoxic conditions. FSallC tumors were treated with 2-10 Gray then the Hoechst 33342 dye diffusion method was used to separate the tumor into bright (enriched in normally oxygenated cells) and dim (enriched in hypoxic cells) subpopulations. There was good agreement between the survival of normally oxygenated cells in culture and bright cells from tumors and between hypoxic cells in culture and dim cells from tumors over a radiation dosage range of 2-5 Gray. At 10 Gray bright cells from tumors were minimally less sensitive to the radiation dose than normally oxygenated cells in vivo. When maximally effective doses of perfluorochemical emulsions (F44E at 4 g PFC/kg or Fluosol-DA at 2.4 g PFC/kg) or a purified bovine hemoglobin solution (PBHS at 1.32 g protein/kg) were administered 1 hr. prior to radiation therapy with carbogen (95% O2, 5% CO2) breathing prior to and during radiation delivery, low single doses of x-ray (2-5 Gray) were measurably more cytotoxic toward both FSallC tumor cell subpopulations. These results indicate that perfluorochemical emulsions or purified bovine hemoglobin preparations along with carbogen breathing may be able to increase tumor radiosensitivity to the relatively low radiation doses per fraction used in the clinic. 相似文献
92.
Distortion and movement of the expander during skin expansion. 总被引:2,自引:0,他引:2
Masamitsu Kuwahara Mitsuo Hatoko Hideyuki Tada Aya Tanaka Satoshi Yurugi Kumi Mashiba 《Nordisk plastikkirurgisk forening [and] Nordisk klubb for handkirurgi》2003,37(1):22-27
Distortion and movement of tissue expanders can cause expansion of the wrong area, such as the naevus or the scar that is to be resected. In 71 rectangular expanders, we examined the incidence of distortion (over 15 degrees) and movement (over 3 cm). We divided the expanders into three anatomical site groups: scalp, body, and extremities, and compared the complication rate between two study groups (distortion or movement, or not). In total, the incidence of distortion was 15/71 (21%) and that of movement 5/71 (7%). Distortion occurred mainly in the extremities (11/33,33%). The implanted expanders tended to move more often in the body part (3/15, 20%). In the extremities, the bigger the angle between the axis of the implanted expander and that of the extremity, the bigger the angle of distortion. Although the incidence of complications between the two groups was not significant, except for alteration in design of the flap, we recommend that these points should be considered when preoperative plans are being made for appropriate patients. 相似文献
93.
Fumonisins as a possible contributory risk factor for primary liver cancer: A 3-year study of corn harvested in Haimen, China, by HPLC and ELISA 总被引:13,自引:0,他引:13
Y. Ueno K. Iijima S.-D. Wang Y. Sugiura M. Sekijima T. Tanaka C. Chen S.-Z. Yu 《Food and chemical toxicology》1997,35(12):1143-1150
Employing HPLC fluorometry, gas-liquid chromatography (GLC) and a novel enzymelinked immunosorbent assay (ELISA) based on a monoclonal antibody, 40 corn samples, each collected in 1993 from agricultural stocks for human consumption in Haimen (Jiangsu County) and Penlai (Shandong Province), high- and low-risk areas for primary liver cancer (PLC) in China, respectively, were analysed for fumonisins (FBs), aflatoxins (AFs) and trichothecenes. Levels and positive rates of FBs and deoxynivalenol (DON) were significantly higher in Haimen than in Penlai. ELISA of the 40 corn samples harvested in the two areas in 1994 revealed that FB contamination levels and rates in these areas were comparable to those observed in 1993 in Haimen. ELISA analysis of 1993 and 1994 products revealed a wide occurrence of AFB1 but the positive rates as well as levels were not significantly different between these areas. ELISA of the same sample number of corn harvested in 1995 revealed that FB contamination in Haimen was significantly higher than in Penlai. These 3-yearly surveys of corn samples (240 in total) demonstrated that corn harvested in Haimen was highly contaminated with FBs and that the contamination level, as well as positive rate in 1993 and 1995, were 10–50-fold higher than those in Penlai, suggesting FBs as a risk factor for promotion of PLC in endemic areas, along with the trichothecene DON. Co-contamination with AFs, potent hepatocarcinogens, was assumed to play an important role in the initiation of hepatocarcinogenesis. 相似文献
94.
Chikako Nishigori Miran Tanaka Shin-ichi Moriwaki Sadao Imamura Hiraku Takebe 《Cancer science》1992,83(11):1172-1178
Skin tumors were produced on the back of hairless mice, HOS (HR/De), by exposure to ultraviolet B light (UVB, 290–320 nm) with 4 different protocols. The first tumors appeared earlier (in 10 weeks in group I and 7 weeks in group III) when initial intense exposure was given, followed by repeated lower-level exposures, than when the mice were exposed to the repeated UV only (in 16 weeks both in group II and group IV). All mice developed skin tumors earlier in the groups given the repeated UV exposures three times a week than in the groups given the exposures twice a week. Most of the skin tumors produced by the UVB exposure were histologically malignant, being transplantable to nude mice, and the cultured cells grown from the tumors were capable of producing tumors when injected into nude mice. The accelerated development of skin tumors by initial intense exposure and short intervals of repeated exposure observed in this study may have implications for humans who expose themselves to intense sunbathing and UV tanning (burning) by fluorescent sun lamps. 相似文献
95.
Y Matsuki K Suzuki M Hara A Kitani T Hirose M Harigai M Kawakami N Tanaka M Kawagoe H Nakamura 《Ryūmachi》1992,32(2):154-9; discussion 159-62
Arterial thrombosis is one of the major symptoms of antiphospholipid syndrome (APS). However, thrombosis in a primary branch of the aorta has rarely been reported in APS. We report here a case of APS complicated by thromboses in both the left subclavian artery and the left external iliac vein. A 32-year-old woman was admitted in May, 1990 complaining of no pulse in the left superficial arteries (e.g., left radial artery) for the past 5 years and acute swelling of the left lower extremity. A left ascending phlebography showed an occlusion of the external iliac vein and arteriography revealed obstruction in the left subclavian artery. Collateral circulations were developed at the site of each thrombus. Clotting and immunological studies revealed a prolonged APTT, a high titer of anticardiolipin antibody and lupus anticoagulant positive. We ruled out various diseases and clinical risk factors predisposing to both arterial and venous thromboses. Accordingly, we concluded that both thromboses were based on APS. Following treatment with anticoagulants, aspirin and corticosteroid, the swelling of her left thigh was diminished and the antibody titer was decreased within 3 months. 相似文献
96.
Seiji Furuya Hiroshi Ogura Yoshinori Tanaka Taiji Tsukamoto Hiroshi Isomura 《International journal of urology》1997,4(5):524-526
The case of a 53-year-old man with hematospermia and massive postejaculation hematuria that caused urinary retention is described. This is the sixth case in the English and Japanese language literature. Cystourethroscopic examination revealed that a solitary raised tumor was present just distal to the vermontanum, and that bleeding was from its apex. Histologic examination of an excisional biopsy sample showed features compatible with hemangioma. 相似文献
97.
H Sanui T M Redmond S Kotake B Wiggert T Tanaka G J Chader I Gery 《Current eye research》1990,9(2):193-199
Monkeys immunized with bovine IRBP-derived synthetic peptides R4 (sequence 1158-1180) or R14 (1169-1191) developed EAU which was detected by both clinical and histological examinations. The inflammation localized mainly in the choroid, with only minor changes being noticed in the adjacent retinal tissue. EAU developed in only one of the two monkeys immunized with each of the peptides and the animals with disease also showed higher levels of cellular immunity toward the immunizing peptide than did the monkeys with no disease. The cellular immune responses, measured by the lymphocyte proliferation assay, were specific toward the immunizing peptides, with no cross responsiveness to whole IRBP. This finding suggests that the two uveitogenic peptides were non-immunodominant in the tested monkeys. In contrast, peptide R14 is highly immunodominant in the Lewis rat. Also, the fine specificity of the monkey response to R14 differed from that of the Lewis rat. The possible genetic control of the monkey susceptibility to EAU induction by the peptides is discussed and the unique finding of an autoimmune disease induction by a non-immunodominant peptide is underscored. 相似文献
98.
S Yamamoto A Senzaki K Yamagiwa T Tanaka T Oda 《Hinyokika kiyo. Acta urologica Japonica》1990,36(5):617-622
We report a case of carcinoma of the prostate in a 30-year-old man. Serum acid phosphatase was normal. A transrectal biopsy of the prostate demonstrated an undifferentiated carcinoma. Total prostatocystectomy was performed and subsequent pathologic report stated that the mass was an undifferentiated carcinoma of the prostate gland. Metastases to the intrapelvic lymph node were present. Although immunohistochemical prostatic acid phosphatase (PAP) activity was not demonstrated, prostatic specific antigen (PSA) staining revealed a positive reaction within the tumor cells, confirming prostatic carcinoma. The patient's course has been uneventful without any recurrence by the intermittent adjuvant chemotherapy 8 months postoperatively. Review of the literature in Japan disclosed 16 cases (including our case) of carcinoma of the prostate in patients under 40 years of age. 相似文献
99.
Although propylene oxide, which is similar in chemical structure to ethylene oxide, is expected to produce neuropathy, there is no convincing evidence of the degeneration of the peripheral nervous system. To determine the exposure concentration of propylene oxide necessary to produce neuropathy in male Wistar rats, we subjected them to repeated exposures of propylene oxide at concentrations of 500, 750, 1000, 1500 and 2000 ppm. The test rats were subjected to a single 6 hour exposure of propylene oxide at a concentration of 1500 parts per million 5 times a week for 3 weeks. They developed a significant decrease in body weight, abnormal posture of the hindlegs and axonal degeneration of myelinated fibers in the peroneal and sural nerves, the nerves to the soleus muscle, and in the fasciculus gracilis of the spinal cord. Therefore, it was concluded that propylene oxide induces neuropathy in rats characterized by axonal degeneration, similar to that produced by ethylene oxide, and that the exposure to the higher concentration of propylene oxide is more necessary to produce neuropathy than in the case of ethylene oxide neuropathy in rats. 相似文献
100.