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991.
David A. Cory Aslam R. Siddiqui Mervyn D. Cohen 《European journal of nuclear medicine and molecular imaging》1987,12(11):546-547
Focal uptake of 99mTc-MDP was seen in a case of hepatoblastoma. The focal uptake corresponded to an area of calcification on CT, which was shown histologically to consist of osteoid with mineralization. The mechanism of uptake by the tumor in this case is likely to be the same as for skeletal uptake. 相似文献
992.
Convergence of Genetic, Nutritional and Inflammatory Factors in Gastrointestinal Cancers 总被引:2,自引:0,他引:2
Gastrointestinal cancers account for 20% of all cancer incidences worldwide. Colorectal cancer is the second most common cause of all cancer-related mortality and is increasing in Western societies. Infection and inflammation contribute to 15–20% of all malignancies, and are predisposing risk factors for gastrointestinal cancers. Helicobacter pylori infection is commonly associated with gastric cancers, and chronic inflammation increases the risk of colorectal cancer by 1% per year. Micronutrient status and common genetic variations in human populations modify risk for gastrointestinal cancer. Chronic inflammation promotes carcinogenesis by inducing gene mutations, inhibiting apoptosis, and stimulating an-giogenesis and cell proliferation. Inflammation also induces epigenetic alterations that are associated with cancer development. Two key genes in the inflammatory process, cyclooxygenase-2 (COX-2) and nuclear factor-kappa B (NF-kB), provide a mechanistic link between inflammation and cancer and are targets for chemoprevention. Dietary components, and human genetic variation that affects nutrient utilization, can directly modify inflammatory processes and/or suppress genomic alterations that are the molecular antecedents of cancers. The present report focuses on the convergence of genetic, nutritional, and inflammatory factors in the initiation and progression of gastrointestinal cancers, and the emerging dietary strategies for cancer prevention. 相似文献
993.
本文就福建省及长乐县全死因回顾调查资料,应用Poisson分布原理分析胃癌死亡人群分布特征。福建省资料x~2=34.9330,P<0.001,不符合Poisson分布,提示全省有高低发区存在。长乐县X~2=0.9312,P>0.05,符合Poisson分布,即胃癌在该县呈高度分散状态,恶性肿瘤的地区分布和致癌因素分布相一致。 相似文献
994.
Mortality among ferrous foundry workers 总被引:8,自引:0,他引:8
M Silverstein N Maizlish R Park B Silverstein L Brodsky F Mirer 《American journal of industrial medicine》1986,10(1):27-43
Mortality analyses were carried out for 278 male hourly workers who were employed for at least 10 years at a gray iron foundry and who died between January 1, 1970 and December 31, 1981. Statistically significant excess proportional mortality due to non-malignant respiratory disease (SPMR = 177), lung cancer (SPMR = 148), and leukemia (SPMR = 284) was found among the 221 white males. Among nonwhite males there was a significant excess in proportional mortality due to circulatory diseases (SPMR = 143). White males in the Finishing classification experienced a significant excess of proportional mortality due to nonmalignant respiratory disease (SPMR = 279) and lung cancer (SPMR = 179). White males in the Core Room classification experienced an excess of proportional mortality due to nonmalignant respiratory disease (SPMR = 321). Case-control studies demonstrated a significant association between nonmalignant respiratory disease and the Finishing classification after controlling for the effects of age, prior occupations in coal mining or foundries, and smoking. A positive but nonsignificant association between lung cancer and Finishing was also found after controlling for age, prior work history, and smoking in case control studies. 相似文献
995.
Although knowledge of functional differentiation and tumour-associated changes of breast carcinomas can be gained by the application of antibodies directed against the milk fat globule membrane, more significant information may be obtained by assessment of the potential of breast carcinomas to modulate their antigenic phenotype. In this study, the extend to which primary tumours can undergo modulation in vitro has been investigated, with consideration of the suitability of organ culture in combination with the immunohistochemical detection of two milk fat globule membrane epitopes, HMFG1 and HMFG2, as methods for detecting this. The preservation of three of the 30 carcinomas assessed, all poorly differentiated, was poor after 3 days of culture. The viability of the other 27 was variable, and was greater in the better differentiated tumours and with the addition of insulin. Expression of the milk fat globule membrane epitopes was generally well maintained. Six of the carcinomas showed a significant change in antigen expression, with this being more frequent in tissues incubated with insulin. Hence, a small group of carcinomas have been identified which appear to have a greater capacity to undergo functional differentiation. Organ culture is considered to be a suitable method for maintaining the tissues in vitro for such evaluation, but the problems encountered in quantifying the immunohistochemical staining, because of antigenic heterogeneity, were such that it is suggested that other approaches be employed. 相似文献
996.
W. -A. Cappeller R. Knitza J. Briegel H. Forst H. Stiegler L. Sunder-Plassmann E. Pratschke 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1992,377(2):100-103
Zusammenfassung Das HELLP-Syndrom (Hemolysis, Elevated Liver enzymes, Low Platelets) tritt als Komplikation einer Schwangerschaftspräeklampsie auf und kann zu ausgedehnten subkapsulären Leberhämatomen führen. Wegen der Rupturgefahr der Hämatome besteht eine lebensbedrohende Notfallsituation für Mutter und Ungeborenes. Anhand von 2 Fallbeispielen wird das interdisziplinäre Vorgehen diskutiert. Mit Diagnosestellung der subkapsulären Leberhämatome sollte die notfallmäßige Entbindung durch Sectio erfolgen. Dann kann die chirurgische Entscheidung für eine konservative, abwartende Therapie mit Intensivüberwachung oder für eine Notfalloperation im Falle einer Leberkapselruptur ohne vermeidbares Risiko getroffen werden.
Subcapsular liver hematoma with HELLP-syndrome — an interdisciplinary urgency
Summary The HELLP-syndrome (Hemolysis, Elevated Liver enzymes, Low Platelets), known as a complication during pregnancy, is associated with preeclampsia and may cause subcapsular liver hematomas. In case of hepatic rupture the lives of mother and unborn are threatened. Therefore, an interdisciplinary diagnostic and therapeutic approach is discussed and compared to two examples. The diagnosis of subcapsular liver hematoma must lead to urgent delivery through Cesarean section. Thereafter, the surgeon may decide between observation on an intensive care unit and urgent operation in case of hepatic rupture, without endangering the unborn.相似文献
997.
拓扑替康在卵巢癌治疗中的新进展 总被引:1,自引:0,他引:1
拓扑替康是一种新的半合成喜树碱衍生物 ,通过抑制拓扑异构酶Ⅰ而产生抗肿瘤作用。大量研究表明拓扑替康对卵巢癌尤其是经铂类药物化疗失败 ,复发的卵巢癌患者有较好疗效。本文就拓扑替康在卵巢癌临床应用中的新进展进行综述。 相似文献
998.
Akihiro Ito Tadateru Takahashi Hiromitsu Watanabe Peter Osa Ogundigie Taro Okamoto 《Cancer science》1992,83(10):1052-1056
Mouse liver tumors occurring in C3H/HeN, C57BL/6N and C3B6F1 hybrid (C3H × C57BL) were studied following 252 Cf fission neutron irradiation. Three strains of mice of both sexes (about 30 mice/group) were irradiated once with 252 Cf at doses of 0,12.5, 50 and 200 cGy. The groups were observed for 13 months after irradiation. The incidence of liver tumors in the non-irradiated controls was 0% in both sexes of CS7BL/6N, 11.7% in males and 0% in females of C3B6F1 and 39.5% in males and 11.4% in females of C3H/HeN mice. In the four strains of mice thus far studied, including B6C3F1 hybrid (CS7BL × C3H) which was previously studied, 252 Cf irradiation has increased the tumor incidence dose-dependently in males and in females, but less effectively in females. The mean number and size of liver tumors were clearly correlated with tumor incidence. The incidence was always highest in C3H/HeN mice of both sexes, followed by B6C3F1, C3B6F1 and C57BL/6N mice. The influence of sex hormones was studied in B6C3F1 mice of both sexes after 200 cGy of 252 Cf irradiation. In males, the incidence of liver tumors was significantly decreased from 55.2% to 23.3% and 25.9% after orchidectomy, and in females it was slightly decreased from 27.6% to 14.8% and 18.8% after ovariectomy. Supplementation of testosterone in orchidectomized mice did not restore the occurrence of liver tumors. 相似文献
999.
1000.
Anal and rectal cancer in Crohn's disease 总被引:3,自引:0,他引:3
Several epidemiological studies have been published regarding the risk of Crohn's disease‐ associated colorectal cancer. The findings are, however, contradictory and it has been particularly difficult to obtain indisputable information on the incidence of cancer limited to the rectum and the anus. During 1987–2000 rectal or anal cancer was diagnosed in 335 patients in Sweden (153 males, 182 females). In other words, approximately 3 Crohn patients per million inhabitants were diagnosed with rectal or anal cancer every year during that time period which is 1% of the total number of cases. At diagnosis of cancer 36% were aged below 50 years and 58% below 60 years. Corresponding figures for all cases of anal and rectal cancer were 5% and 18%, respectively. Present knowledge from the literature implies that there is an increased risk of rectal and anal cancer only in Crohn's disease patients with severe proctitis or severe chronic perianal disease. However, the rectal remnant must also be considered a risk factor. Multimodal treatment is similar to that in sporadic cancer but proctectomy and total or partial colectomy is added depending on the extent of the Crohn's disease. The outcome is the same as in sporadic cancer at a corresponding stage but the prognosis is often poor due to the advanced stage of cancer at diagnosis. We suggest that six high‐risk groups should be recommended annual surveillance after a duration of Crohn's disease of 15 years including extensive colitis, chronic severe anorectal disese, rectal remnant, strictures, bypassed segments and sclerosing cholangitis. 相似文献