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51.
Ritva Valavaara Juhani Tuominen Auli Toivanen 《Cancer immunology, immunotherapy : CII》1990,31(6):381-386
Summary The immune status of breast cancer patients was followed during antiestrogen treatment for at least 1 year or until progression of the disease. Twelve postmenopausal women with advanced estrogen-receptor-positive breast cancer were treated with a novel antiestrogen, toremifene. Immune functions were determined before the start of the treatment and at 3, 6, and 12 months. For NK cell cytotoxicity testing there were 74 healthy controls and for T cell subset measurements 28 healthy controls. No statistically significant changes in the T cell subsets or NK cell cytotoxicity were observed during treatment. However, throughout toremifene treatment patients had fewer CD4 cells (T helper lymphocytes) than did the controls. Cancer patients had higher pretreatment B cell values than the controls,P = 0.01, but during the first months of toremifene treatment B cell values decreased and remained within the normal range thereafter. A positive effect on mitogen-stimulation tests with phytohemagglutinin (PHA) and concanavalin A (ConA) was observed during the first months of treatment (P = 0.01 for PHA and 0.03 for log [ConA] and a stabilization at the higher level thereafter. These results indicate that toremifene has a stimulatory effect on cell-mediated immunity in breast cancer patients. 相似文献
52.
Although aleurone grains of certain oilseeds (e. g. peanuts)are exceedingly sensitive to aqueous solutions, it has beenreported that aleurone grains maintain their integrity whenhomogenized in an aqueous solution containing 15% Carbowax 6000(PEG-6000). Presumably this substance acts as an osmotic agent.We have been unable to confirm this result using microscopicand chemical studies. However, we found that PEG-6000 acts asa protein precipitant; therefore, it is suggested that the pelletobtained upon centrifugation of the homogenate is mostly proteinprecipitate rather than intact aleurone grains.
1Fulbright-Hayes Research Scholar 19721973. Present address:Dept. of Cell Biology, Univ. of Jyvaskyla, Vapaudenkatu 4, SF-40100,Jyvaskyla 10, Finland. (Received May 13, 1974; ) 相似文献
53.
Juhani Lehtonen 《Nordic Journal of Botany》1983,3(4):521-531
The effects of cytochalasin B on the development and morphology of the Micrasterias cell vary according to different developmental stages. CB (especially 5–6 μm/ml) does not stop the growth of a developing semicell during early developmental stages and allows the formation of a three–lobed form, which is a kind of a basic form preceding the actual morphogenesis, further growth and development still being totally prevented by the same concentration. This is due to the occurrence of two separate cytoplasmic streaming systems in the developing semicell, one being cortical, more CB sensitive, the other being more central, not as sensitive to CB, both being microfilament based. The cortical streaming system supports tip growth, and many observations indicate that this system is also associated with the intermediation of the nuclear control regulating morphogenesis in Micrasterias. The effects of CB are specific: it has not been found to have distinct effects on the ultrastructure of the cell, on cell wall material production, or on the turgor pressure of the cell. 相似文献
54.
Abstract 5-Methyl-2′-deoxycytidine 5′-[32P]- and deoxycytidine 5-[32 P]-monophosphates were prepared from corresponding nucleotide homopolymers by using a 32 P-postlabeling procedure. The radioactive monophosphates obtained were well suited for biological and biochemical experiments. 相似文献
55.
Iodinated melatonin: preparation and characterization of the molecular structure by mass and 1H NMR spectroscopy 总被引:3,自引:0,他引:3
Olli Vakkuri Erkki Lämsä Erkki Rahkamaa Heikki Ruotsalainen Juhani Leppäluoto 《Analytical biochemistry》1984,142(2):284-289
Synthetic melatonin was iodinated by treatment with potassium iodide in the presence of an oxidizing agent, Iodo-Gen. The iodination products of melatonin were extracted with chloroform and separated by HPLC. The fraction showing immunoreactivity with respect to melatonin antisera was characterized as iodomelatonin by mass spectrometry, so that the substitution of iodine had occurred at a ring carbon atom. 1H NMR spectra showed the iodine to be incorporated at the C-2 position of the indole moiety. The N-[2-(2-iodo-5-methoxy-1H-indol-3-yl)ethyl]acetamide (2-iodomelatonin) reported here is more useful than [3H]melatonin as a tracer in melatonin radioimmunoassay. This method offers also the possibility of preparing iodinated serotonin and other indoleamines for biological studies. 相似文献
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In many species, males rely on sexual ornaments to attract females. Females, by contrast, rarely produce ornaments. The glow-worm (Lampyris noctiluca) is an exception where wingless females glow to attract males that fly in search of females. However, little is known about the factors that promote the evolution of female ornaments in a sexual selection context. Here, we investigated if the female ornament of the glow-worm is a signal of fecundity used in male mate choice. In support of this, we found brightness to correlate with female fecundity, and males to prefer brighter dummy females. Thus, the glow emitted by females is a reliable sexual signal of female fecundity. It is likely that male preference for the fecundity-indicating ornament has evolved because of large variation among females in fecundity, and because nocturnal males cannot directly assess female size and fecundity. These results indicate that female ornamentation may evolve in capital breeders (i.e. those in which stored resources are invested in reproduction) when females vary significantly in fecundity and this variation cannot be assessed directly by males. 相似文献
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60.
Glycomics of bone marrow-derived mesenchymal stem cells can be used to evaluate their cellular differentiation stage 总被引:1,自引:0,他引:1
Annamari Heiskanen Tia Hirvonen Hanna Salo Ulla Impola Anne Olonen Anita Laitinen Sari Tiitinen Suvi Natunen Olli Aitio Halina Miller-Podraza Manfred Wuhrer André M. Deelder Jari Natunen Jarmo Laine Petri Lehenkari Juhani Saarinen Tero Satomaa Leena Valmu 《Glycoconjugate journal》2009,26(3):367-384
Human mesenchymal stem cells (MSCs) are adult multipotent progenitor cells. They hold an enormous therapeutic potential, but
at the moment there is little information on the properties of MSCs, including their surface structures. In the present study,
we analyzed the mesenchymal stem cell glycome by using mass spectrometric profiling as well as a panel of glycan binding proteins.
Structural verifications were obtained by nuclear magnetic resonance spectroscopy, mass spectrometric fragmentation, and glycosidase
digestions. The MSC glycome was compared to the glycome of corresponding osteogenically differentiated cells. More than one
hundred glycan signals were detected in mesenchymal stem cells and osteoblasts differentiated from them. The glycan profiles
of MSCs and osteoblasts were consistently different in biological replicates, indicating that stem cells and osteoblasts have
characteristic glycosylation features. Glycosylation features associated with MSCs rather than differentiated cells included
high-mannose type N-glycans, linear poly-N-acetyllactosamine chains and α2-3-sialylation. Mesenchymal stem cells expressed SSEA-4 and sialyl Lewis x epitopes. Characteristic
glycosylation features that appeared in differentiated osteoblasts included abundant sulfate ester modifications. The results
show that glycosylation analysis can be used to evaluate MSC differentiation state. 相似文献