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101.
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
102.
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104.
本院1966年~1989年共收治小儿卵黄囊瘤37例,经血清甲胎蛋白(AFP)测定,光镜确定诊断又通过10例电镜观察,8例AFP免疫组化观察,文献复习,本文支持Teilum提出该瘤来源于卵黄囊瘤背壁的全能性生殖细胞的组织发生观点;1.胚胎卵黄囊有合成AFP能力,本文意儿血清AFP明显升高,免疫酶标可作AFP定位。2.超微结构观察:肿瘤形态与妊娠7周卵黄囊相似,电镜下可见到上皮性及间叶性成份相当于胚外内胚层及胚外中胚层成份。且讨论了该瘤的命名与畸胎瘤关系和免疫组化的应用 相似文献
105.
Takakura Yoshinobu Fujita Takuya Hashida Mitsuru Sezaki Hitoshi 《Pharmaceutical research》1990,7(4):339-346
As part of the strategy for the design of macromolecular carriers for drug targeting, the disposition characteristics of macromolecules were studied in mice bearing tumors that served as target tissues. Eight kinds of macromolecules including four polysaccharides and four proteins with different molecular weights and electric charges were used; tissue distribution and tumor localization after intravenous injection were studied. Pharmacokinetic analysis revealed that the tissue radioactivity uptake rate index calculated in terms of clearance was different among the tested compounds; especially, the urinary radioactivity excretion clearances and the total hepatic radioactivity uptake clearances varied widely. Compounds with low molecular weights (approximately 10 kD) or positive charges showed lower tumor radioactivity accumulation; radioactivity was rapidly eliminated from the plasma via rapid urinary excretion or extensive hepatic uptake, respectively. On the other hand, large and negatively charged compounds, carboxymethyl dextran, bovine serum albumin, and mouse immunoglobulin G, showed higher radioactivity accumulation in the tumor (calculated total amounts were 15.6, 10.8, and 20.8% of the dose, respectively) and prolonged retention in the circulation. These results demonstrated that the total systemic exposure rather than the uptake rate index was correlated with total tumor uptake. Molecular weight and electric charge of the macromolecules significantly affected their disposition characteristics and, consequently, determined radioactivity accumulation in the tumor. It was concluded that a drug–carrier complex designed for systemic tumor targeting should be polyanionic in nature and larger than 70,000 in molecular weight. 相似文献
106.
Clinicopathologlc and mucin histochemical characteristics of 90 cases of ovarian mucinous borderline tumors (MBT) of Intestinal (IMET) and müllerian types (MMBT) were studied to determine whether IMBT and MMBT constitute distinct tumor subtypes. The IMBT (77 cases, 78 lesions) contained goblet cells, absorptive cells and endocrine cells, which represented Intestinal differentiation. The average diameter of IMBT was 13.4 cm. Five patients (6.5%) had stage III disease wtth pseudomyxoma perltonel and one of them died from tumor. Approximately 50% of IMBT demonstrated gastrointestinal characteistics on mucin histochemistry. The MMBT (13 cases, 14 lesions) consisted of mumus columnar cells and eosinophilic cells, with no Intestinal differentiation. MMBT accounted for 15.2% of MBT. MMBT averaged 8.4 cm in diameter, and 29% were associated with endometriosls of the ipsilateral ovary. All patients with MMBT had stage I disease, and none suffered from pseudomyxoma peritonel. All patients whose follow-up data were available were alive and well, without evidence of tumor recurrence. The mucin histochemical findings in MMBT resembled those of noml endocervix. Results of the present study suggest that IMBT and MMBT have different characteristics and constitute distinct subtypes of MBT. 相似文献
107.
HepatocelularCarcinomawithTumorThrombusinPortalVein:FindinginUltrasonography,ComputedTomography,AngiographyandChemoembolizati... 相似文献
108.
膀胱癌是泌尿外科最常见的恶性肿瘤织一 ,由于复发率较高 ,死亡率逐年上升 ,防止肿瘤发生、发展和侵袭转移是降低膀胱癌高复发率和死亡率的关键。随着人们对膀胱肿瘤发生的分子生物学机制研究的深入 ,相关生物学标志物的相继问世以及某些化学药品和食品防癌作用的发现 ,尤其是癌症化学防治取得的一定的成功 ,使得防止和逆转膀胱肿瘤癌前病变成为可能 ,为此 ,本文对膀胱肿瘤化学防治近年的研究进展进行综述 ,为预防和控制膀胱肿瘤提供指导 相似文献
109.
G. Borkowski H. Sudhofft H. Luckhauptt S. Philippou H. Hildmann 《European journal of plastic surgery》1997,20(2):107-109
Dermatofibrosarcoma protuberans (DFSP) previously called Morbus Darier is an intermediate grade sarcoma with a fairly high rate of recurrence, it occurs most commonly on the trunk and extremities but may also occur in the head and neck region. Treatment of choice is wide excision. A 69-year-old female patient with a 57-year history of dermatofibrosarcoma protuberans is presented. The lesion appeared on the right forehead and both eyelids at the age of 12 years. The patient required 64 surgeries mostly for the head and neck lesions. 相似文献
110.
Tetsuji Kai Yang Il Kim Hirokazu Kitamura Katsunori Kawano Seigo Kitano 《Journal of Hepato-Biliary-Pancreatic Surgery》1997,4(4):423-430
There is a growing body of evidence that the cytokine, tumor necrosis factor-α (TNF-ga), plays an important role in the development
of hepatic ischemia/reperfusion injury. We found that the immunosuppressants, cyclosporine-A (CsA), azathioprine, and FK506,
have protective effects on such injury. The purpose of the present study was to elucidate mechanisms involved in these beneficial
effects of the immunosuppressant, CsA, on liver injury following cold preservation and transplantation, with special reference
to the suppression of TNF-α release. Rat livers were stored in Euro-Collins solution (EC) at 4°C for 6h and orthotopically
transplanted. The animals allotted to two groups: group A (untreated controls) and group B (CsA pretreatment of recipients).
CsA (10 mg/kg, p.o.) was given for 3 consecutive days preoperatively. CsA pretreatment of the recipients significantly improved
the 2-week survival rate (0/6 for group A, 3/6 for group B;P<0.05) and this was associated with a significant decrease in serum TNF-α levels 2h posttransplantation (group A, 69.8±15.7
pg/ml; group B, 22.8±6.8; mean±SEM;n=12 each;P<0.05) and amelioration of sinusoidal endothelial injury, assessed by electron microscopy. Plasma endotoxin levels following
reperfusion of the grafts were not altered by the CsA therapy. Morphologically, CsA pretreatment of the recipients did not
alter activation of Kupffer cells. CsA pretreatment of the recipient aids in preventing cold preservation/reperfusion injury
of the liver graft, possibly by modulating effects of TNF-α. 相似文献