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排序方式: 共有9069条查询结果,搜索用时 718 毫秒
81.
Takada D Emi M Ezura Y Nobe Y Kawamura K Iino Y Katayama Y Xin Y Wu LL Larringa-Shum S Stephenson SH Hunt SC Hopkins PN 《Journal of human genetics》2002,47(12):0656-0664
82.
The effects of the antioxidant alpha-lipoic acid (LA) on the proliferation of mitogen-stimulated human peripheral blood lymphocytes (HPBL) were investigated in comparison to its effects on the proliferation of two leukaemic T cell lines, Jurkat and CCRF-CEM. At low mM concentrations, LA inhibited in a dose-dependent manner DNA synthesis of HPBL stimulated with either phorbol myristate acetate (PMA) in combination with ionomycin (IoM), or phytohaemagglutinin (PHA). At similar concentrations, LA inhibited the proliferation of Jurkat and CCRF-CEM cells. However, LA was preferentially cytotoxic to the leukaemic cell lines. The selective toxicity of LA to Jurkat cells was shown by electron microscopy (EM) to be due to the induction of apoptosis. Furthermore, LA had different effects on the secretion of interleukin-2 (IL-2) and steady-state levels of IL-2 mRNA in mitogen-stimulated HPBL depending on the mitogens used. LA dramatically increased the induction of IL-2 mRNA and IL-2 protein secretion in PMA/IoM-stimulated HPBL, whereas it inhibited these in HPBL stimulated with PHA. The differential effects of LA on normal and leukaemic T lymphocytes may indicate a new route towards development of therapeutic agents. 相似文献
83.
Henry M Kuerer George E Peoples Aysegul A Sahin James L Murray S Eva Singletary Agapito Castilleja Kelly K Hunt David M Gershenson Constantin G Ioannides 《Journal of interferon & cytokine research》2002,22(5):583-592
HER-2/neu peptides have recently been shown to induce a proliferative response by peripheral CD4(+) T cells in breast cancer patients. To investigate potential differences in the local cellular immune response between breast cancer patients with and without nodal metastases, lymphocytes were isolated from axillary lymph nodes from patients with breast cancer, and proliferative and cytokine responses to HER-2/neu peptides were determined. Freshly isolated lymphocytes from lymph nodes of 7 women undergoing surgery for invasive breast cancer were plated at 20 x 10(5) cells per well in triplicate. Cells were stimulated with HER-2/neu peptides at 50 microg/ml and with control antigens. Incorporation of tritium-labeled thymidine was determined 4 days later. The levels of the cytokines interferon-gamma (IFN-gamma), interleukin-4 (IL-4), and IL-10 were determined at priming and at restimulation with HER-2/neu peptides using a cytokine-specific, double-sandwich, enzyme-linked immunosorbent assay (ELISA). Lymphocytes isolated from the axillary lymph nodes of the patients mounted significant cellular immune response to HER-2/neu peptides, manifested by proliferation and specific cytokine elaboration. Proliferative responses to HER-2/neu peptides were seen in lymphocytes of patients with and without overexpression of HER-2/neu in the primary tumor. In some patients, the proliferative response to HER-2/neu peptides in lymphocytes from lymph nodes with metastases was absent or blunted compared with the response in lymphocytes from lymph nodes without metastases from the same patient (p < 0.05). HER-2/neu peptides induced a predominantly T helper type 1 (Th1) pattern of cytokine response in nodal lymphocytes isolated from breast cancer patients. A Th1-specific cytokine production pattern was maintained at priming and restimulation with HER-2/neu peptides and was amplified with IL-12 costimulation. These results indicate that HER-2/neu peptides can activate T cells in draining lymph nodes from women with invasive breast cancer. This activation is associated with a predominantly Th1 cytokine response, which suggests that conditioning with HER-2/neu peptides may be of value in the development of breast cancer vaccines. 相似文献
84.
Analyses of the H-2D/L-related glycoproteins from dm1 mutant cell extracts by sequential immunoprecipitation, by SDS gel electrophoresis and by tryptic peptide mapping indicate that dm1 cells express only a single glycoprotein with H-2D/L-related determinants. In contrast to the four H-2D/L-related antigens identified for the parental d haplotype viz. H-2Dd, H-2Md, H-2Ld and H-2Rd, separate and distinguishable "H-2Ddm1", "H-2Mdm1", "H-2Ldm1" and "H-2Rdm1" glycoprotein counterparts are apparently lacking in the dm1 mutant haplotype. Only a single H-2D/L-related glycoprotein is identified in dm1 extracts by standard serological methods and this glycoprotein is designated H-2D/Ldm1 because of its H-2Dd/H-2Ld hybrid characteristics, as recently shown by Burnside and colleagues (1984). Thus, the seemingly complex phenotype of the dm1 mutant appears to originate primarily from one molecule having properties of two (or more) molecules of the parental haplotype. 相似文献
85.
R. H. Foote E. E. Swierstra W. L. Hunt 《Anatomical record (Hoboken, N.J. : 2007)》1972,173(3):341-351
The cycle of the seminiferous epithelium of the dog was divided into eight stages, using as criteria the shape of the spermatid nucleus, the location of spermatids and spermatozoa in regard to the basement membrane, the presence of meiotic figures and the release of spermatozoa from the lumen of the tubule. Based upon these criteria, a modification of the eight-stage system of classification of the cycle of the seminiferous epithelium was developed. Cell populations making up each stage are described. The relative frequencies of stages 1 through 8 were 21.9, 12.7, 2.8, 11.5, 8.3, 15.4, 13.3 and 14.0%, respectively. The duration of one cycle of the seminiferous epithelium was 13.6 days (SE ± 0.7), as determined from cells labeled by tritiated thymidine. The absolute durations of stages 1 through 8 were 3.0, 1.7, 0.4, 1.6, 1.1, 2.1, 1.8 and 1.9 days, respectively. The life span of primary spermatocytes was 20.9 days, of secondary spermatocytes 0.5 days, spermatids with round nuclei 10.5 days, spermatids with elongated nuclei up to the time they are released into the lumen, 10.6 days. Counts of the different types of spermatogenic cells in tubular cross sections revealed little or no germ cell degeneration during the two maturation divisions. 相似文献
86.
Intratympanic injections of sodium arsanilate (atoxyl) have been shown to produce vestibular dysfunction in the rat. Unilateral and bilateral dysfunction can be distinguished by changes in the animals' postures. These changes are consistent with changes described for unilateral or bilateral labyrinthectomized rats. The intratympanic injection technique offers a simple yet effective alternative to labyrinthectomy. 相似文献
87.
This paper describes the tragic case of a young woman who died of cancer of
the colon after successfully donating eggs to her younger sister. Although
there is no direct link between her operation and the subsequent
development of bowel carcinoma, this case imparts a feeling of unease when
seen in conjunction with other cases reported during the last few years. It
is a reminder that little is known of the long-term consequences of some
aspects of assisted conception. Women undergoing ovarian stimulation for
themselves or a matched recipient have the right to be advised, in an
agreed format, that there is some concern about unproven potential risks
from the stimulatory drugs. The safety of egg donors must assume priority
over all other considerations, including lack of donors or any moral
position. The recent decision by the Human Fertilisation and Embryology
Authority (HFEA) to withdraw any form of payment or recompense to egg
donors does not seem to us to be based on a balance of scientific advances,
patient needs and the ethics of gamete supply. They state that the
intention to withdraw payments was implicit in the 1990 Human Fertilisation
and Embryology (HFE) Act. However the Act was based on the Warnock report
made 6 years earlier. Even in 1990 ovum donation was uncommon and fertility
drugs had not yet caused any unease. The Act provided the HFEA with
discretionary powers to issue directions so that the future policies would
be consistent with any emerging new medical evidence. It is imperative that
the HFEA provide convincing evidence on how the current policy of payment
to donors harms society, donors or recipients, and how in the UK the new
policy will improve medical practice in assisted conception. Successful
pilot studies must precede the implementation of any new policy. Failure to
do this could cause irreversible harm to the practice of assisted
conception using donor gametes, which will ultimately be against the basic
aims of the 1990 HFE Act.
相似文献
88.
Mutations in the Ca(2+)-sensing receptor gene cause autosomal dominant and sporadic hypoparathyroidism 总被引:3,自引:0,他引:3
Baron J; Winer KK; Yanovski JA; Cunningham AW; Laue L; Zimmerman D; Cutler GB Jr 《Human molecular genetics》1996,5(5):601-606
Parathyroid hormone secretion is negatively regulated by a 7- transmembrane
domain, G-protein coupled Ca(2+)-sensing receptor. We hypothesized that
activating mutations in this receptor might cause autosomal dominant
hypoparathyroidism (ADHP). Consistent with this hypothesis, we identified,
in two families with ADHP, heterozygous missense mutations in the
Ca(2+)-sensing receptor gene that cosegregated with the disorder. None of
50 normal controls had either mutation. We also identified a de novo,
missense Ca(2+)-sensing receptor mutation in a child with severe sporadic
hypoparathyroidism. The amino acid substitution in one ADHP family affected
the N-terminal, extracellular domain of the receptor. The other mutations
involved the transmembrane region. Unlike patients with acquired
hypoparathyroidism, patients with these mutations had hypercalciuria even
at low serum calcium concentrations. Their greater hypercalciuria
presumably reflected activation of Ca(2+)-sensing receptors in kidney
cells, where the receptor negatively regulates calcium reabsorption. This
augmented hypercalciuria increases the risk of renal complications and thus
has implications for the choice of therapy.
相似文献
89.
Tissue and lineage-specific variation in inactive X chromosome expression of the murine Smcx gene 总被引:2,自引:0,他引:2
To understand how gene expression patterns are established on the inactive
X chromosome during development, we have studied the murine gene Smcx,
which is expressed from both the active and inactive mouse X chromosomes.
In all tissues assayed, Smcx only partially escapes X inactivation, with
expression levels from the inactive X allele approximately 30-65% that of
the active X allele. Additionally, inactive X expression levels differed
between extraembryonic and embryonic tissues and among different tissues
from newborn and adult mice. Imprinted extraembryonic tissue had the lowest
levels of inactive X Smcx expression, whereas the highest levels were in
heart. These data suggest that the chromosomal basis of X inactivation
differs among tissues, perhaps reflecting differences in the timing or
regulation of inactivation in these cell lineages.
相似文献
90.
Clinical and pathological variability of infection by enterohaemorrhagic (Vero cytotoxin producing) Escherichia coli. 总被引:1,自引:1,他引:1 下载免费PDF全文
The clinical and pathological features of five sporadic cases of enteric infection caused by Escherichia coli O157 (enterohaemorrhagic or Vero cytotoxin-producing E coli showed a range of features. These included one case with pseudomembranous colitis, one with an acute exacerbation of ulcerative colitis, and three with enterocolitis. Diagnostic difficulties encountered initially in four of the five cases were finally resolved by correlating the results of microbiological with histopathological investigations. In view of the heterogeneity of clinical and histological signs and symptoms, it is concluded that all patients with abdominal pain and diarrhoea or rectal bleeding should have early microbiological investigation. 相似文献