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81.
Summary Adenosine deaminase complexing protein (ADCP), a dimeric glycoprotein, has been reported to be decreased or deficient in transformed or cancer-derived cell lines, indicating its potential significance as an indicator of malignant transformation. A similar deficiency was reported in total homogenates of tumours of colon, kidney, lung and liver. In previous biochemical studies we failed to confirm the consistent reduction in ADCP concentration in cancer tissues. A possible explanation for our findings was thought to be intercellular heterogeneity in ADCP expression in individual tumour cells. To study ADCP expression in individual cells we developed an immunohistochemical method which was applied to tissue sections. Paraformaldehyde-lysine-periodate (PLP) solution was found to be a suitable fixative. Fixed tissue samples were paraffin-embedded, sectioned and stained for ADCP, using an indirect peroxidase-labelled antibody procedure. The protein was localized in normal colonic mucosa, mainly in the brush border region of the luminal epithelium and in cytoplasmic granules. Intense ADCP immunoreactivity was found also in the basal part of some cells. In cancer cells, three staining patterns were observed: membranous, diffuse cytoplasmic and granular cytoplasmic. The adenocarcinomas exhibited significant intratumour and intertumour heterogeneity in their staining types.Further studies on ADCP expression in colorectal cancer in relation to clinical and histopathological characteristics are warranted in order to fully evaluate the potential significance of ADCP as a cancer associated antigen.  相似文献   
82.
Life history parameters were determined for glucose-averse (glu/glu), wild-type (glu+/glu+) and heterozygous (glu/glu+) genotypes of Blattella germanica (L.) (Blattodea: Blattellidae) fed diets supplemented with glucose. Glu/glu nymphs consumed less glucose-supplemented diet, gained less weight, developed slower and had a lower rate of survival than glu/glu nymphs fed the same diet without added glucose, or glu+/glu+ and glu/glu+ fed either diet. Prior to formation of the first oötheca, female glu/glu consumed less glucose-supplemented diet per day than glu+/glu+ and glu/glu+, which presumably delayed egg case production. Oötheca-bearing glu/glu and glu/glu+ females consumed less glucose-supplemented diet than glu+/glu+ females. Despite a difference in female total diet intake, there was no effect of diet or genotype on fecundity. However, the intrinsic rate of increase (r) for glulglu on unsupplemented diet was less than that of glu+/glu+ and glu/glu+, suggesting that individuals with both glu alleles may be at a selective disadvantage in environments lacking diets containing glucose plus a toxicant.  相似文献   
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Summary Binding parameters were determined for four mouse monoclonal antibodies reacting with three antigens on the surface of fresh human ovarian carcinoma ascites cells, under nearly physiological conditions. The object of these experiments was to aid in the selection of the optimal monoclonal antibodies for intraperitoneal immunotherapy. The number of antigenic sites per cell, the effective equilibrium association constant (affinity) and the half-life for dissociation were: for Ab MH99, 1.2×106 sites/cell, (1.9–4.1)×108M–1, and 4 h; for Ab MX35, (3.2–4.1)×105 sites/cell, (3.4–4.8)×108M–1, and >10 h; and for Ab MW207, 1.3×105 sites/cell, (3.6–4.1)×109M–1, and 3.1 h, respectively. One of the antigens, MH99, is recognized by five different monoclonal antibodies, and competitive inhibition experiments demonstrated that two distinct determinants are present; this antigen is also recognized by the previously described Ab 17-1A. These binding data will aid the rational design of immunotherapy strategies.  相似文献   
86.
Summary Immunoregulation of phytohemagglutinin (PHA) responsiveness by glass-adherent cells and prostaglandin-synthesizing cells was serially monitored in the peripheral blood mononuclear cells (PBMC) of surgically resected stage I and stage II lung cancer patients entered on a trial of adjuvant immunotherapy. The relationship between immunoregulatory cell function, immunocompetence, and disease relapse was determined. Immunoregulatory activity was measured in PHA-stimulated cultures in the presence and absence of 2 g/ml indomethacin and in the presence and absence of glass-adherent cells. In each instance of disease relapse seen, an increase in immunoregulatory cell function to a level significantly different from normal was observed 3 months prior to or coincident with clinical confirmation of disease recurrence. This was usually associated with a decline in PHA responsiveness. In the patients who did not relapse, the levels of PHA responsiveness and immunoregulatory function persisted within normal limits throughout the course of study. Percentages and numbers of leukocytes and leukocyte subsets and delayed cutaneous hypersensitivity were also monitored in this study, but could not be consistently correlated with early changes in clinical disease status. These data suggest that the development of indomethacin-sensitive and glass-adherent suppressor cells may precede and predict for tumor recurrence in surgically resected lung cancer patients.  相似文献   
87.
Summary The effects of cytotoxic chemotherapy on NK cell function and on glass adherent cell regulation of NK cell function was evaluated in the peripheral blood mononuclear cells of 20 previously untreated solid tumor patients. Most of the patients studied had lung cancer and received one of four combination chemotherapy treatment regimens. In addition, one patient with colon carcinoma and one patient with melanoma were studied, each of whom received treatment with a single agent. The results demonstrated that chemotherapy exerted a differential influence on NK activity which correlated with the pretreatment NK level of function in the individual patient. In patients with depressed NK levels prior to treatment, chemotherapy augmented NK function; in patients with normal levels prior to treatment, chemotherapy depressed NK function. The effects observed appeared to be associated with the capacity of chemotherapy to influence glass adherent cell regulation of NK activity. There was no apparent correlation between the effects of chemotherapy on numbers of NK effector cells, Leu11+ cells, or latex-ingesting cells. Also, there was no correlation between the effects seen and the type of drug treatment that was administered; rather, this was dependent on the pretreatment NK level of function which in turn was associated with glass adherent cell regulation of NK function.Supported in part by PHS Grant No. 27598  相似文献   
88.
RNA-dependent DNA polymerase activity was found in peparations of a mutant of Newcastle disease virus. The enzyme activity was not found in wild-type virus preparations.  相似文献   
89.
Bose , Smritimoy , and Jules Janick . (Purdue U., Lafayette, Ind.) Karyo-races in Spinacia oleracea. Amer. Jour. Bot. 48(3): 238–241. Illus. 1961.—Cytological analysis of chromosome 1 of Spinacia oleracea, which contains the XY factor pair, revealed the existence of 3 distinct morphological types. The “standard” chromosome 1, the longest of the complement, is heterobrachial with one arm being about twice as long as the other. The most prevalent situation is for this “standard” chromosome pair to be homomorphic in staminate, monoecious, or pistillate plants. Some staminate and pistillate plants in the varieties ‘Spica’ and ‘Universal’ were found to be heteromorphic for the standard chromosome and a variant type, distinguished by a satellite on the short arm. In a cross derived from an accession PI 169671 from Turkey, which segregated for monoecious and pistillate types, half of the plants, irrespective of sex, were homomorphic for the standard chromosome and half were heteromorphic. The non-standard chromosome was longer and isobrachial, the added length apparently due to an additional segment on the short arm of the “standard” chromosome. Plants homomorphic for the satellited and isobrachial chromosome have been obtained.  相似文献   
90.
In the Carboniferous, insects evolved flight. Intense selection drove for high performance and approximately 100 million years later, Hymenoptera (bees, wasps and ants) emerged. Some species had proportionately small wings, with apparently impossible aerodynamic challenges including a need for high frequency flight muscles (FMs), powered exclusively off aerobic pathways and resulting in extreme aerobic capacities. Modern insect FMs are the most refined and form large dense blocks that occupy 90% of the thorax. These can beat wings at 200 to 230 Hz, more than double that achieved by standard neuromuscular systems. To do so, rapid repolarisation was circumvented through evolution of asynchronous stimulation, stretch activation, elastic recoil and a paradoxically slow Ca2+ reuptake. While the latter conserves ATP, considerable ATP is demanded at the myofibrils. FMs have diminished sarcoplasmic volumes, and ATP is produced solely by mitochondria, which pack myocytes to maximal limits and have very dense cristae. Gaseous oxygen is supplied directly to mitochondria. While FMs appear to be optimised for function, several unusual paradoxes remain. FMs lack any significant equivalent to the creatine kinase shuttle, and myofibrils are twice as wide as those of within cardiomyocytes. The mitochondrial electron transport systems also release large amounts of reactive oxygen species (ROS) and respiratory complexes do not appear to be present at any exceptional level. Given that the loss of the creatine kinase shuttle and elevated ROS impairs heart function, we question how do FM shuttle adenylates at high rates and tolerate oxidative stress conditions that occur in diseased hearts?  相似文献   
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