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41.
Epstein-Barr virus (EBV)-immortalized human B cells survive only transiently when injected subcutaneously into athymic mice, whereas Burkitt's lymphoma cells give rise to progressively growing subcutaneous tumors. In this study, we tested whether these Burkitt's tumors could be induced to regress via a bystander effect induced by EBV-immortalized B cells. Simultaneous inoculation of EBV-immortalized B cells and Burkitt's lymphoma cells in the same subcutaneous site resulted in tumors that regressed with necrosis and scarring. Similarly, simultaneous inoculation of EBV-immortalized B cells and Burkitt's lymphoma cells in separate subcutaneous sites resulted in regression of a proportion of the Burkitt's tumors. Furthermore, most of the established human Burkitt's tumors regressed with necrosis and scarring after intratumor inoculations with EBV-immortalized B cells. The EBV-immortalized B cells continued to exert this antitumor effect even when killed with irradiation. The experimental approach to Burkitt's lymphoma treatment described here exploits the ability of athymic mice to reject EBV-immortalized B cells to target an effective antitumor response to malignant cells normally incapable of eliciting it.  相似文献   
42.
很久以来都认为遗传成分参与2型糖尿病(T2DM)的发病,但是有关遗传学上的发现一直进展缓慢,这是由于遗传成分的复杂性。有关糖尿病相关的各种表型的研究的大量资料提示,所谓的“T2DM”可能是许多疾病的统称,由于它们具有通常相互重叠的多种基本发病机制。因此,对曾抱有期望的T2DM的遗传学基础的寻求已经证明是很艰难的。  相似文献   
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1. Insomnia is an even more frequent complaint in elderly patients with Parkinson's disease than might be expected from the effect of age alone on sleep. 2. A double-blind, placebo-controlled trial in eleven patients with Parkinson's disease of mean (s.d.) age 80(5) years, showed that nocturnal dosing with levodopa produced a clinically significant improvement in sleep both as assessed subjectively and by measurement of number of spontaneous moves in bed. 3. Despite the long interval between tablet administration and morning assessment, walking time was faster on mornings following active treatment.  相似文献   
45.
Kiel  KD; Rademacker  AW 《Radiology》1996,198(1):279
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STUDY OBJECTIVE--This analysis aimed to compare the response rates of those invited to attend for screening in a multicentre, multinational study within Europe. DESIGN--This was a population survey. SETTING--Thirty four centres in 16 European countries. SUBJECTS--Men and women aged 50 years and over were recruited from population based sampling frames to participate in a prevalence survey of osteoporosis. Subjects were invited by post to attend for radiological screening and interview, and non-responders were followed up by repeat mailing. RESULTS--There was a substantial variation between centres in response rates: the mean was 49% and the range 5-83%. Adjusting for those known to have died or moved house did not affect the overall ranking. The response rates to each mailing also varied between centres: first mailing 45% (range 5-83%) and second mailing mean 10% (range 0-23%). The response rates varied in relation to age and sex and were higher in women than men. Rates fell gradually with age in women but rose in men until the age of 65 years. Response rates varied regionally. These were highest in countries from northern Europe and lowest in southern European countries, but there was wide variation both within regions and within countries. CONCLUSIONS--Multicentre, multinational studies within Europe will probably become increasingly popular. In this study, despite a standardised approach, the range in response rates between centres both within and between countries was substantial. Attempts at cross national standardisation in survey design can have only a limited effect on yielding uniformity in response.  相似文献   
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Attempts were made to isolate Chlamydia trachomatis from the cervix of 300 women attending a clinic for sexually transmitted diseases in Leeds. The women were divided into four groups; (1) 130 were consorts of men suffering from non-specific urethritis; (2) 66 were suffering from gonorrhoea, or were consorts of men suffering from this disease; (3) 56 were suffering from other sexually transmitted diseases; (4) 48 had no evidence of STD. The overall isolation rate of Chlamydia trachomatis was 20%. Positive results were obtained in 30%. of Group 1, in 27-3%. of Group 2, in 3-6%. of Group 3, and in 2-1%. of Group 4. No pathogenic sign or symptom of Chlamydia trachomatis infection of the cervix was detected.  相似文献   
50.
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