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121.
齐墩果酸免疫治疗恶性肿瘤病人的临床Ⅱ期研究   总被引:3,自引:0,他引:3  
前瞻性双盲法临床研究,可评价的恶性肿瘤病人28例,口服齐墩果酸40mg,每日3次,1个月后测定吞噬细胞百分比,由54.1%提高至67.42%。吞噬指数由0.69提高至0.81。迟发超敏反应1:1000浓度转阳性率52.6%(10/19)。E-玫瑰花结试验在本组试验前后无显著变化。同期服用安慰剂的9例对照病人则无变化。治疗后齐墩果酸对骨髓、肝、肾功能均无影响,故可做为比较理想的生物反应调节剂应用于临床,以促进病人的免疫功能。  相似文献   
122.
This paper reports the prevalence of chronic esophagitis and nutritional status among 538 young persons aged 15 to 26 years from the high risk area for esophageal cancer. Of these subjects, 166 were from households with history of esophageal cancer and 372 were from households without history of esophageal cancer. The Incidences of chronic esophagltis among male and female adolescents were 37. 6% and 36% respectively, which was significantly higher than those in the low risk area (17%). The frequency of chronic esophagltis in the adolescents in the households with history of esophageal cancer was aiso higher than in those In the households without history of esophageal cancer. The deficiencies of vitamins, especially of riboflavin and ascorbate, are prevalent and severe among these adolescents. Ascorbate deficiency Is correlated with the severity of the chronic esophagltis. These results indicate that chronic esophagltis may be involved in the natural history of esophageal carclnogenesis. Nutrient defic  相似文献   
123.
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   
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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   
127.
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   
128.
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   
129.
HepatocelularCarcinomawithTumorThrombusinPortalVein:FindinginUltrasonography,ComputedTomography,AngiographyandChemoembolizati...  相似文献   
130.
戴贵东  王心如 《卫生研究》2003,32(2):159-162
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   
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