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The interactions between the tumor and its host are complex, and many aspects of the immune system appear to be adversely affected directly or indirectly by the presence of the tumor. Virtually all of the processes involved in immune induction and action have been implicated in the observed deficient response in tumor-bearing patients. Improved understanding and molecular analysis of the mechanisms underlying the escape of tumors from immune surveillance may lead to the development of novel strategies for the prevention of T-cell immunosuppression in cancer patients, the development of novel immunotherapeutic strategies, and potentially prevention of tumor progression or development. 相似文献
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SD Detera-Wadleigh JA Badner T Yoshikawa AR Sanders LR Goldin G Turner DY Rollins T Moses JJ Guroff D Kazuba ME Maxwell HJ Edenberg T Foroud D Lahiri JI Nurnberger OC Stine F McMahon DA Meyers D MacKinnon S Simpson M McInnis JR DePaulo J Rice A Goate ES Gershon 《Canadian Metallurgical Quarterly》1997,74(3):254-262
25.
HV Thomas TJ Key DS Allen JW Moore M Dowsett IS Fentiman DY Wang 《Canadian Metallurgical Quarterly》1997,76(3):401-405
The associations between serum concentrations of oestradiol, testosterone and sex hormone-binding globulin (SHBG) and risk of breast cancer in post-menopausal women were investigated in a prospective study on the island of Guernsey. Sixty-one women who developed breast cancer an average of 7.8 years after blood collection were matched for age, year of blood collection and number of years post-menopausal with 179 control subjects. Women using exogenous hormones at the time of blood collection were excluded from the study. Women who subsequently developed breast cancer had a 29% higher geometric mean oestradiol concentration than control women (P = 0.004). The odds ratio for breast cancer in the top third compared with the lowest third of the oestradiol concentration distribution was 5.03 (95% confidence interval 2.02-12.49, P for trend < 0.001). Adjusting for testosterone and SHBG concentrations did not substantially alter the odds ratio for oestradiol. Although testosterone and SHBG concentrations were associated with breast cancer risk, the concentrations of these hormones were correlated with those of oestradiol; the associations were not statistically significant after adjusting for oestradiol concentration. These data provide evidence that serum oestradiol concentrations in post-menopausal women may have a substantial effect on breast cancer risk. 相似文献
26.
Holmes Clarissa S.; Cornwell John M.; Dunlap William P.; Chen Ru San; Lee Cheok Y. 《Canadian Metallurgical Quarterly》1992,6(4):341
The factor structure of the Wechsler Intelligence Scale for Children—Revised (WISC—R) was analyzed with 95 diabetic children (aged 8–16 yrs), 97 regionally and demographically matched controls, and an age- and race-matched sample from the WISC—R standardization sample (n?=?1,405). Controls exhibited a 3-factor IQ structure, consistent with the standardization sample. Diabetic Ss exhibited a 4-factor structure, with the Perceptual Organization factor splitting in two. Picture Completion (PC) and Picture Arrangement (PA) formed a visual discrimination factor, and Block Design and Object Assembly created a spatial conceptual factor. Among the diabetic Ss, the PC and PA subtests did not act as traditional measures of nonverbal intelligence, and the performance of diabetic Ss on the visual discrimination factor may reflect mild visual atypicalities. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
27.
RJ Guo Y Wang E Kaneko DY Wang H Arai H Hanai S Takenoshita K Hagiwara CC Harris H Sugimura 《Canadian Metallurgical Quarterly》1998,19(9):1539-1544
Mutations in the transforming growth factor beta type II receptor (TGFbetaRII) gene have been detected in several human cancer types exhibiting microsatellite instability. Using intron primers previously reported for examination of the entire coding region of the TGFbetaRII gene, 29 sporadic gastric cancers were screened with non-radioactive single strand conformation polymorphism and subsequent DNA sequencing analysis. Mutations of the TGFbetaRII gene were detected in three out of 29 tumors (10%). Two cases showed deletions in a polyadenine tract in both alleles and was positively associated with replication error. One case had an insertion of GA dinucleotide sequence in one allele. Mutations of the TGFbetaRII gene were restricted to exon 3 and other coding regions were not affected. Loss of heterozygosity was detected by analyzing a polymorphic site in intron 2. Three out of nine (33%) informative cases, which were all of intestinal type and advanced cases, showed loss of heterozygosity but neither TGFbetaRII mutation nor replication error was found in these cases. Immunoreactivity of TGFbetaRII in tumor tissues was reduced to a different extent in the gastric cancer with genetically abnormal transforming growth factor. Although the numbers studied are small, homozygous (A)10 deletion or loss of heterozygosity of TGFbetaRII is involved in tumorigenesis and progression of at least some part of sporadic gastric cancer. 相似文献
28.
A Ben-Amor MC Leite-De-Moraes F Lepault E Schneider F Machavoine A Arnould L Chatenoud M DY 《Canadian Metallurgical Quarterly》1996,103(3):491-498
Anti-CD3 MoAb treatment is widely used as an immunosuppressive therapy. In the present study we examined the in vitro T cell response in mice having received 24 h before a single i.v. injection of 10 microgram of anti-CD3 MoAb. We found that splenocytes from these mice displayed a dramatically decreased proliferative response to the T cell mitogens concanavalin A (Con A), anti-CD3, phytohaemagglutinin (PHA) and phorbol myristate acetate (PMA) + calcium ionophore, while the effect of lipopolysaccharide (LPS) was not impaired. T cell suppression persisted for about 10 days after anti-CD3 injection, returning to normal within 15 days. The F(ab')2 fragment of anti-CD3 had no such effect, indicating the requirement for in vivo activation. At the dose used, anti-CD3 resulted neither in T cell depletion nor in down-modulation of the CD3/T cell receptor (TCR) complex. The low proliferation was also not explained by apoptosis, following secondary challenge with Con A. Splenocytes from anti-CD3-injected mice were highly responsive to IL-2, but generated little or no IL-2, IL-3, IL-4 and interferon-gamma (IFN-gamma) when exposed to Con A. Normal cytokine production could not be restored by the addition of optimal doses of IL-2 during Con A stimulation. Transforming growth factor-beta (TGF-beta) was the only cytokine whose mRNA expression was not modified in stimulated splenocytes from anti-CD3-injected mice. Furthermore, anti-TGF-beta antibodies increased Con A-induced T cell proliferation, but not cytokine production. 相似文献
29.
Schulman J.N. Holabird K.S. Chow D.H. Dunlap H.L. Thomas S. Croke E.T. 《Electronics letters》2002,38(2):94-95
The current against voltage characteristics of Sb-heterostructure zero-bias millimetre-wave diodes were measured from 15 to 81°C. No significant variation in the zero-bias junction resistance or curvature coefficient was found. The new diode is the first that provides temperature independent direct detection capability at and beyond W-band 相似文献
30.
T Schubert DY von Cramon T Niendorf S Pollmann P Bublak 《Canadian Metallurgical Quarterly》1998,9(14):3171-3176
We investigated cortical areas involved in the control of self-determined finger movements. In a tapping task, subjects tapped with different movement frequencies in two different movement conditions (predetermined vs self-determined). fMRI provided evidence for the involvement of the horizontal and ascending parts of the intraparietal sulcus (IPS), the left superior frontal gyrus and the posterior cingulate gyrus in the control of self-determined finger movements. Higher movement frequency increased the extent of activated area only in the horizontal part of IPS. The results suggest a major role of the IPS in controlling sequences of finger movements. This area probably serves as a region for integration of motor, sensory and sensorimotor feedback information used for movement control. 相似文献