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241.
Marie Lipoldová Helena Havelková Jana Badalová Jarmila Vojtíšková Lei Quan Magdaléna Krulová Yahya Sohrabi Alphons P. Stassen Peter Demant 《Cancer immunology, immunotherapy : CII》2010,59(2):203-213
Low infiltration of lymphocytes into cancers is associated with poor prognosis, but the reasons why some patients exhibit
a low and others a high infiltration of tumors are unknown. Previously we mapped four loci (Lynf1–Lynf4) controlling lymphocyte infiltration of mouse lung tumors. These loci do not encode any of the molecules that are involved
in traffic of lymphocytes. Here we report a genetic relationship between these loci and the control of production of IFNγ
in allogeneic mixed lymphocyte cultures (MLC). We found that IFNγ production by lymphocytes of O20/A mice is lower than by
lymphocytes of OcB-9/Dem mice (both H2
pz
) stimulated in MLC by irradiated splenocytes of C57BL/10SnPh (H2
b
) or BALB/cHeA (H2
d
) mice, or by ConA. IFNγ production in MLCs of individual (O20 × OcB-9)F2 mice stimulated by irradiated C57BL/10 splenocytes and genotyped for microsatellite markers revealed four IFNγ-controlling
loci (Cypr4-Cypr7), each of which is closely linked with one of the four Lynf loci and with a cluster of susceptibility genes for different tumors. This suggests that inherited differences in certain
lymphocyte responses may modify their propensity to infiltrate tumors and their capacity to affect tumor growth. 相似文献
242.
Herman van der Putten Wim Quint Janny van Raaij Els Robanus Maandag Inder M. Verma Anton Berns 《Cell》1981,24(3):729-739
M-MuLV-specific DNA probes were used to establish the state of integration and amplification of recombinant proviral sequences in Moloney virus-induced tumors of Balb/Mo, Balb/c and 129 mice. The somatically acquired viral sequences contain both authentic M-MuLV genomes and recombinants of M-MuLV with endogenous viral sequences. All reintegrated genomes carry long terminal repeat (LTR) sequences at both termini of their genome. In the preleukemic stage a large population of cells exhibiting a random distribution of reintegrated M-MuLV genomes are seen, but during outgrowth of the tumor, selection of cells occurs leaving one or a few clonal descendants in the outgrown tumor. In this latter stage recombinant genomes can be detected. Although these recombinants constitute a heterogeneous group of proviruses, characteristic molecular markers are conserved among many individual proviral recombinants, lending credence to the notion that a certain recombinant structure is a prerequisite for the onset of neoplasia. The structure of these recombinants shows close structural similarities to the previously described mink cell focus-inducing (MCF)-type viruses. 相似文献
243.
In this paper, we present a model for the development of connections between muscle afferents and motoneurones in the human spinal cord. The model consists of a limb with six muscles, one motoneurone pool, one pooled (Ia-like) afferent for each muscle and a central programme generator. The weights of the connections between the afferents and the motoneurone pools are adapted during centrally induced movements of the limb. The connections between the afferents and the motoneurone pools adapt in a hebbian way, using only local information present at the synapses. This neural network is tested in two examples of a limb with two degrees of freedom and six muscles. Despite the simplifications, the model predicts the pattern of autogenic and heterogenic monosynaptic reflexes quite realistically. 相似文献
244.
245.
Peter
hman 《Acta zoologica》1971,52(2):287-297
The outer segment of long and short photoreceptors in the retina of the river lamprey, Lampetra fluviatilis, were studied by light- and fluorescence microscopy together with some different electron microscopic methods. The outer segments show characteristics of both rods and cones and are suggested to represent intermediate kinds of photoreceptors. 相似文献
246.
Caroline van Haaften-Day Peter Russell Susan Carr Lesley Wright 《In vitro cellular & developmental biology. Plant》1988,24(10):965-971
Summary A cell line derived from a human ovarian carcinosarcoma was established in tissue culture and in nude mice. Two sublines,
LDF and HDF, separated by discontinuous density centrifugation were also established from the parent line JoN. The cloning
efficiency of the JoN line was 21%. Morphologic features of adenocarcinoma cells characteristic of the parent JoN cells were
retained in the sublines and clones; all lines showed the same karyotype and DNA content (pseudodiploid and pseudotetraploid).
Keratin, as demonstrated immunohistochemically, was strongly expressed in the parent line JoN and the xenograft tumor, but
not at all in the LDF sublines and only moderately in the HDF sublines. Vimentin, however, was expressed in neither the parent
line JoN nor the xenograft tumor, but was present in both sublines. Transglutaminase and plasminogen activator activity was
high in the parent line JoN. Neither, sublines nor clones showed the same high enzyme activity as the parent line. It is concluded
that this human tumor line JoN is comprised of epithelial cells, capable of multidirectional differentiation. 相似文献
247.
Peter V Scott 《BMJ (Clinical research ed.)》1982,285(6350):1277-1278
248.
The isolation of mutants of Saccharomyces cerevisiae that divide at approximately half the size of the wild type is described. Three mutants have been isolated in which the small size at bud initiation is due to a mutation in a single nuclear gene. 相似文献
249.
The improvement of glass capillary preparation technology has allowed the development of high-resolution and very low-bleeding gas chromatographic columns. Using an all-glass injector and a flame ionization detector, it was possible to get a complete resolution of some of the principal stable oxygenated metabolites of arachidonic acid (cyclized and aliphatic, i.e., eicosanoids). Due to the low bleeding of the column, detector limits exceed those obtained with previously prepared columns. Total profiling studies have been obtained with small amounts of activated washed platelets after only an ether extraction, allowing for the first time a complete, simultaneous survey of cycloxygenase and lipoxygenase pathways. The application has been extended with success to other cell types. 相似文献
250.