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991.
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A previous experiment (Herzfeld & Taub, 1977) demonstrated that slide projections and explicit suggestions relating to thermal experiences can significantly augment temperature self-regulations training (.5 degrees F, p less than .05). however, the experimental design was thought to result in an underestimate of the magnitude of the effect, since each subject served as his own control and could therefore make use on nonsuggestion training days of material provided on training days. In this experiment, separate groups of subjects either were given feedback combined with the suggestion procedure on each of 8 training days or were given feedback alone. The mean temperature self-regulation of the suggestion group (2.01 degrees F) was significantly better than the self-regulation (.73) of the nonsuggestion group (t test, p less than 0.01), a difference of 1.28 degrees F.  相似文献   
995.
Platinum(II) binding to metallothioneins   总被引:1,自引:0,他引:1  
The reaction of equine renal metallothionein (MT) with excess K2PtCl4 at pH 2 results in a polymeric adduct containing 17 +/- 2 mol Pt/mol MT. A monomeric adduct containing 7 mol Pt/mol MT is obtained at neutral pH. Rates of reaction of Pt7MT with DTNB and iodoacetic acid are consistent with Pt2+ to cysteine thiolate coordination, and the extent of reaction in both cases is 11 +/- 2 mol cys/mol MT. Adducts from the reaction of K2PtCl4 with apoMT chemically modified at the N-terminal methionine residue, Cd7MT, and native MT are also reported. A structural model of Pt7MT is proposed in which the square planar tetrathiolate Pt(II) unit is incorporated into a three-metal beta cluster. Implications for the metabolism of platinum anticancer drugs are discussed.  相似文献   
996.
Recent data have demonstrated that differences in sIg density on B lymphocytes distinguish functionally distinct subpopulations of these cells. Other reports suggest that cyropreservation may change the frequency of sIg-bearing lymphocytes. To determine if cryopreservation alters either the frequency of sIg cells or the distribution of sIg density, PBM from normals and patients with CLL and LCL were analyzed using the FACS. Aliquots of Ficoll-Hypaque-separated PBM were controlled-rate frozen (1 °C/min) in 7.5% Me2SO in RPMI 1640 and thawed in a 37 °C water bath on the same day. Fresh and frozen-thawed PBM aliquots were labeled with fluorescein conjugates of F(ab′) fragments of affinity chromatography-purified anti-Fab or class-specific anti-μ, anti-δ, anti-γ, or anti-α. Histograms of relative cell fluorescence, reflecting sIg density, were prepared for each aliquot with the FACS. The frequency of sIg-bearing PBM labeled with each reagent was not significantly altered by freezing. Likewise, FACS profiles demonstrated that the distribution of sIg density on normal and CLL PBM was unchanged after freezing. However, the fluorescence peak produced by frozen-thawed unlabeled cells was occasionally slightly broader than that of fresh cells, suggesting increased autofluorescence induced by freezing. These data indicate that frozen cell preparations may be utilized for the study of B-lymphocyte subsets as determined by sIg density.  相似文献   
997.
998.
Recent theoretical work on the cooperative equilibrium binding of myosin subfragment-1-ADP to regulated actin, as influenced by Ca2+, is extended here to the cooperative steady-state ATPase activity of myosin subfragment-1 on regulated actin. Exact solution of the general steady-state problem will require Monte Carlo calculations. Three interrelated special cases are discussed in some detail and sample computer (not Monte Carlo) solutions are given. The eventual objective is to apply these considerations to in vitro experimental data and to in vivo muscle models.  相似文献   
999.
We screened a total of 460 stool samples from humans with and without underlying disease for the black yeast and neurotrope, Exophiala dermatitidis using conventional and molecular identification procedures. Sixteen (3.5%) samples were positive. Twelve out of the sixteen positive samples where the fungus was recovered were from individuals who had diarrhoea at the moment of isolation. Two asymptomatic positive cases were within the age bracket of 21–30. Susceptibility testing of the strains using the CLSI M38 protocol suggests that almost all the strains were susceptible to amphotericin B, 5 fluorocytosine, itraconazole, fluconazole and voriconazole. Considering the health risk currently posed by this organism in Asia, especially among healthy younger subjects of the population and the scarcity of data on this fungus in Africa in general and Nigeria in particular, some recommendations were suggested.  相似文献   
1000.
Tree size, survival, and coppicing of micropropagated plantlets, macropropagated cuttings, and seedlings of Eucalyptus grandis Hill ex Maiden were monitored through 57 months in a study in southern Florida to assess propagation options. Two plantlet lines developed by direct micropropagation and orchard open-pollinated seedlings from three ortets were compared in the main study. Rooted cuttings from up to four ramets of each of the three ortets and another ortet were examined in an adjacent supplemental study. Freezes at six and 16 months killed most initial and first-coppice stems to the ground. Most developmental differences in the main study were consistent from ages 2 to 57 months. Propagation by ortet interactions were observed beginning at 21 months, due to the poor performance of seedlings of one ortet after the second freeze. At 57 months, no differences in tree height, DBH, volume, or survival were detected between plantlet lines and between rooted cuttings and plantlets, but seedlings were inferior to plantlets and cuttings. Vegetative propagules had more uniform tree size at every age, with typically less than one-half the variability observed among seedlings. Even though plantlets and cuttings may be more expensive to produce, they have numerous advantages over seedlings for E. grandis plantation establishment in Florida.  相似文献   
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