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991.
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   
992.
This study examines the pulmonary hemodynamics during reimplantation and rejection following unilateral lung transplantation in dogs. Nineteen mongrel dogs were divided into three groups according to the method of treatment used: group 1 (n = 6) underwent modified autotransplantation of the left lung; group 2 (n = 6), allotransplantation without immunosuppression; and group 3 (n = 7), allotransplantation with immunosuppression. The pulmonary arterial blood flow and ventilation scores, assessed by chest X-rays, were measured for 2 weeks postoperatively. Pulmonary blood flow to the transplanted lung decreased slightly in group 1, whereas in group 2, it decreased sharply from the 3rd postoperative day (POD) and was almost completely absent by the 14th POD. In group 3, it decreased by 28% on the 1st POD but recovered gradually to 37% by the 14th POD. Ventilation scores were the same among the three groups on the 1st POD but in group 2, they decreased rapidly from the 3rd POD. This change correlated well with that of the pulmonary arterial (PA) flow, although the ventilation score changed after the PA flow did. In conclusion, rejection was reflected earlier and more distinctly by the changes in PA flow than by chest X-rays.  相似文献   
993.
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   
994.
995.
To investigate the efficacy of i.v. IgG treatment in pediatric patients with inflammatory lung disease, a prospective, controlled clinical trial was carried out over a 2-year study period. Patients were enrolled on the basis of severe clinical symptomatology. After 1 year of conventional treatment, the patients received 400 mg/kg per month of an i.v. IgG product containing only trace amounts of IgG3 in addition to their regular treatment throughout the second year. Significant clinical improvement, as documented by duration of hospital stay (first year 27.8 days, second year 4.9 days), use of antibiotics (132.8 versus 30.9 days) and use of steroids (21.4 versus 0.7 days) could be observed. Data obtained on a subgroup of patients with IgG3 deficiency were analysed separately. These results indicate that patients with severe chest disease who have IgG3 deficiency will also benefit from i.v. IgG treatment. The mode of action cannot be attributed to replacement of the respective isotypes, but is probably due to the effect of i.v. IgG in preventing repeated viral infections.  相似文献   
996.
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   
997.
Early gastric cancer manifested as brain metastasis: Report of a case   总被引:1,自引:0,他引:1  
A case of early gastric cancer, limited to submucosal layer, which was manifested as cerebral metastasis is presented herein. A 47-year-old man was admitted to Nagaoka Chuo General Hospital with convulsions and a disturbance in consciousness, where a computed tomography (CT) scan revealed a cerebral tumor in the left temporal lobe. The resected tumor was identified as a metastatic adenocarcinoma. Further investigation revealed gastric cancer involving the posterior wall of the cardia. At laparotomy, multiple and small metastases of the liver and a jejunal metastasis were found, and a palliative total gastrectomy was performed. The surgical specimen revealed a protruding, poorly differentiated medullary adenocarcinoma, with invasion of the submucosal layer. The patient died 4 months after undergoing the laparotomy. This case report is presented to make clinicians aware of the possibility that early gastric cancers may present as brain metastasis.  相似文献   
998.
This study set out to compare the long-term palatability of three oral sip-feed supplements. Sixty patients with various malignancies were randomized to receive one of three products—Build-Up, Fortimel and Fortisip. Participants were encouraged to take as much of the supplements each day for as long as they could manage. At the initial tasting, palatability and acceptability of the products was recorded and this was repeated throughout the trial period. Patients' reasons for discontinuing the trial were noted.
Build-Up was found to be the best-tolerated product of the three. It was taken for a significantly longer time than either Fortimel or Fortisip. There was an indication that Build-Up was more acceptable at the initial tasting than Fortisip but not Fortimel. A smaller proportion of patients stopped taking Build-Up due to flavour-related reasons compared to Fortisip but there was no significant difference between Build-Up and Fortimel. In all, 54% of the patients discontinued the trial for flavour-related reasons. Thirty-five per cent found that the sip-feeds they had been allotted unpalatable at the initial tasting, while 19% stopped the trial due to 'flavour fatigue'. Only 10% of the sample continued taking their allotted product for 90 days or more.  相似文献   
999.
U.S. cancer mortality data derived from information recorded on death certificates are frequently relied upon as an indicator of progress against cancer. A limitation of this measure is the lack of information pertaining to the onset of disease, such as year-of-diagnosis, age-at-diagnosis, stage of disease at diagnosis and histology of lesions. However, population-based cancer registries collect these types of data and allow the calculation of an incidence-file based mortality rate. This incidence-based mortality rate allows a partitioning of mortality by variables associated with the cancer onset. Breast cancer incidence-based mortality measures are created and compared to mortality rates based on death certificates over a comparable time period. Novel mortality measures, such as mortality rates by stage-at-diagnosis, age-at-diagnosis and year-of-diagnosis, are used to illustrate the value of this approach.  相似文献   
1000.
作者合成了13个对-苯二甲酸衍生物,其中有9个化合物尚未见文献报道。通过对HL-60细胞诱导分化活性试验,发现有两个化合物在浓度为5×10 ̄(-6)mol/L时,可使细胞分化率达55%,低于维A酸的分化率(79%,10 ̄(-7)mol/L)。  相似文献   
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