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Fas ligand (FasL), a cell surface molecule belonging to the tumor necrosis factor family, binds to its receptor Fas, thus inducing apoptosis of Fas bearing cells. In the present study we assessed the expression of Fas, activation molecule interleukin (IL)-2 receptor alpha chain (CD25) and an index of functional activity such as thymidine uptake under mitogen stimulation of tumor associated lymphomonocytes (TALM) from 7 neoplastic effusions of advanced cancer patients. The same parameters were studied in peripheral blood mononuclear cells (PBMC) of 7 patients with cancer of different sites and in 7 normal subjects. The proliferative response to phytohemagglutinin (PHA), measured as [3H]-thymidine uptake, of TALM was significantly lower than that of PBMC of cancer patients. The expression of CD25 on unstimulated fresh TALM was slightly higher than that of PBMC from normal subjects: after 24 h of PHA stimulation the CD25 was expressed both on TALM and PBMC from normal subjects. The expression of Fas was assessed on unstimulated TALM, PBMC from cancer patients and normal subjects immediately after (by 2 h, t0) the cell separation, and at different times (24 h and 48 h) thereafter, and on PHA-stimulated TALM, PBMC from cancer patients and normal subjects after 24 h and 48 h of culture (in RPMI 1640). At all times (t0, 24 h and 48 h) the Fas expression by unstimulated TALM was significantly higher than that of PBMC from normal subjects: the Fas expression by PBMC from cancer patients was roughly in the same range as PBMC from normal subjects. At 24 h the Fas expression by PHA-stimulated TALM was significantly higher than that of PBMC from normal subjects, whereas at 48 h the difference was not significant. The TALM studied by us showed to be functionally defective and expressing relatively high levels of Fas showing the characteristics to be considered as a target for FasL expressing tumor cells, which in this way may escape immune control. 相似文献
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KC Donaghue JM Fairchild A Chan SJ Hing J King NJ Howard M Silink 《Canadian Metallurgical Quarterly》1997,10(6):579-585
In the light of recent experiences and anticipating an increase in similar requests in the future, it seemed very interesting to a drug safety executives' group from the pharmaceutical industry to propose guidelines for the set-up and follow-up of pharmacoepidemiological studies requested by Health Authorities for the assessment of drug risk. The scope of these guidelines is to establish the responsibility of the teams and structures involved in the study, to define the necessary stages set-up, and to determine the rules in order to ensure its smooth running from the drafting of the protocole to the final use of the data. 相似文献
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SE Wakefield DW Wheeler NJ Mortensen MG Kettlewell 《Canadian Metallurgical Quarterly》1998,24(6):525-527
AIMS: Two previous studies (1966-1971 and 1979-1983) of patients with colorectal cancer (CRC) have been reported from our hospital. A large increase in the incidence of CRC was noted, and an improvement in Dukes' staging of tumours at treatment. We report a series of patients admitted with newly diagnosed CRC to evaluate this trend further. METHODS: A prospective study was made of all patients with newly diagnosed CRC admitted to the John Radcliffe Hospital, Oxford in 1995. Means of diagnosis and Dukes' staging were recorded. RESULTS: In 1 year 177 patients were admitted with newly diagnosed CRC. Previous studies had shown an increase from 52.8 to 103.4 patients per year. The number of patients diagnosed by colonoscopy doubled from 19.4% in 1979-1983 to 41% in 1995. No significant change in the proportion of patients with Dukes' A or B tumours was found. CONCLUSION: The number of patients treated annually with CRC in a stable population has more than trebled in the last 3 decades. A real increase in the incidence of CRC is likely as this rise cannot be explained solely by changing referral patterns or an ageing community. There are no significant changes in presentation patterns despite the availability of colonoscopy since 1975. 相似文献
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KZ Guyton M Gorospe X Wang YD Mock GC Kokkonen Y Liu GS Roth NJ Holbrook 《Canadian Metallurgical Quarterly》1998,3(1):23-27
BACKGROUND: In the current environment of increasing health care efficiency, the benefits of patient self-history questionnaires need to be fully explored. The utility and reliability of new-patient self-history questionnaires have been documented in the medical literature. This study investigates the prevalence of these patient self-history forms in primary care offices. METHODS: A sample of primary care offices listed in the yellow pages by specialty were surveyed by telephone. Survey questions included the use of new-patient self-history questionnaires as well as other characteristics about the offices. Findings from offices using questionnaires were compared with findings from offices not using questionnaires. RESULTS: Of 129 offices contacted by telephone, 116 (90 percent) responded. Of the 116 offices surveyed, 53 percent were using new-patient self-history questionnaires. Offices using questionnaires had more patients in managed care (P = 0.028) and fewer patients insured by Medicare or Medicaid (P = 0.002). There were no significant differences in other office characteristics. CONCLUSIONS: This study shows that primary care offices underutilize new-patient self-history questionnaires. 相似文献
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A 50 year old patient is described who presented with parkinsonism, frontal dementia, peripheral neuropathy, neurogenic bladder, and upper motor neuron signs. No improvement in objective measurements of extrapyramidal dysfunction were seen with an incremental apomorphine test or more prolonged oral dopamine challenge. Neurophysiology disclosed changes compatible with a diffuse axonal neuropathy and pathological examination of a length of sural nerve taken at biopsy showed multiple polyglucosan bodies characteristic of adult polyglucosan body disease (APGBD). This case underlines the diverse clinical presentation of this rare neurological disease and the importance of recognising the unusual association of clinical features in making the diagnosis. APGBD should be included in the differential diagnosis of parkinsonism unresponsive to dopaminergic therapy. 相似文献
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