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111.
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Human immune interferon preparations have anticellular activity on human cell lines (WISH and HEp-2). This anticellular activity copurified with the human immune interferon and appears to be a function of the immune interferon molecule. On the basis of a unit of antiviral activity, purified human immune interferon had about 20 and 100 times more anticellular activity than purified fibroblast or leukocyte interferon, respectively. The possible implications of this finding in the treatment of human neoplasia are discussed.  相似文献   
113.
N C Franklin  G N Bennett 《Gene》1979,8(1):107-119
Nucleotide sequence has been determined for the restriction fragments and cloned DNA from the pL-N-tL1 region of bacteriophage lambda. A unique reading frame for the N gene is defined by the absence of natural nonsense codons and by the presence of seven nonsense codons generated by mutations in N. This reading frame is initiated at two alternative ATG codons, the second of which is probably the in vivo translation start. Reading is stopped at a single TAG codon. The protein coded is therefore 133 or, more probably, 107 amino acids long, rich in lysine, arginine and proline.  相似文献   
114.
The sequence of the Fc fragment of human IgG3 was studied, using a naturally-occurring γ3 heavy chain variant (ZUC). Though the molecule is internally deleted, it contains 248 residues, including the entire Fc fragment. The almost complete sequence of the CH2 and CH3 domains (position 234 to 446) indicates an extremely close evolutionary relationship with γ1 and γ4 chains. There is a 95% homology between IgG3 and IgGl and 92% between IgG3 and IgG4 in the CH2 in the CH3 domains.  相似文献   
115.
L C Costello  R Franklin  R Stacey 《Enzyme》1976,21(6):495-506
Mitochondrial preparations isolated from rat ventral prostate were capable of oxidizing isocitrate by way of NADP isocitrate dehydrogenase (NADP-IDH) and NAD-IDH. NAD-IDH activity required ADP for activation. The pH responses for NAD-IDH and NADP-IDH were quite different. The results indicated that two different enzymes were involved in the NAD- and NADP-IDH activities. Indirect evidence indicated that NADPH-NAD transhydrogenase activity might also be involved in the mitochondrial pathway for isocitrate oxidation. NADP-IDH activity was significantly greater than NAD-IDH activity. The oxidation of isocitrate through IDH activity was coupled to the cytochrome system by NADPH- and NADH-cytochrome c reductase activities. Citrate, via isocitrate, oxidation proceeded at a much slower rate suggesting that aconitase activity could be limiting in the oxidation of citrate. In comparison to other tissues, the prostate oxidative enzyme activities are considerably lower. The results suggest that the accumulation of high prostate citrate levels is not due to a limitation imposed by a lack of IDH activity in prostate mitochondria.  相似文献   
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Summary The initial attachment of transforming DNA to competent Bacillus subtilis is temperature independent between 25° and 45°. However, below 15° there is a significant reduction in the amount of DNA attached to competent cells. The DNA that is attached at 4° can lead to transformation or interfere effectively with the subsequent attachment of a distinctive DNA when the cells are shifted to a permissive temperature (37°). These data suggest that the attachment of DNA at 4° is to sites normally involved in the transformation process. The amount of DNA that is initially attached to the bacteria at 4° or 37° after perturbation of the cells by ionic strength changes, repetitive washings, or periodate oxidation varies with the temperature at which the treatment occurs. These results are consistent with a reorientation of the DNA attachment sites upon lowering the temperature to 4°, such that their affinity for DNA and susceptibility inhibitory treatments are reduced.National Institutes of Health Research Career Program Awardee, CA-K3-6487 during a portion of this investigation.  相似文献   
118.
Research across groups and methods consistently finds a gender difference in patterns of specificity of genital response; however, empirically supported mechanisms to explain this difference are lacking. The information-processing model of sexual arousal posits that automatic and controlled cognitive processes are requisite for the generation of sexual responses. Androphilic women’s gender-nonspecific response patterns may be the result of sexually-relevant cues that are common to both preferred and nonpreferred genders capturing attention and initiating an automatic sexual response, whereas men’s attentional system may be biased towards the detection and response to sexually-preferred cues only. In the present study, we used eye tracking to assess visual attention to sexually-preferred and nonpreferred cues in a sample of androphilic women and gynephilic men. Results support predictions from the information-processing model regarding gendered processing of sexual stimuli in men and women. Men’s initial attention patterns were gender-specific, whereas women’s were nonspecific. In contrast, both men and women exhibited gender-specific patterns of controlled attention, although this effect was stronger among men. Finally, measures of attention and self-reported attraction were positively related in both men and women. These findings are discussed in the context of the information-processing model and evolutionary mechanisms that may have evolved to promote gendered attentional systems.  相似文献   
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Status asthmaticus in the 1980s is still occasionally a fatal disorder. Preventable causes appear to be common: failing to appreciate the severity of the illness and undertreatment, particularly with steroids. Thus, an objective data base, early treatment, and frequent reassessment are of paramount importance. Despite intensive therapeutic intervention, mechanical ventilation may be required. In managing the ventilator in these patients, efforts should be directed at minimizing peak airway pressures while vigorous conventional modalities are continued. The need to use mechanical ventilation does not imply that the course of the disease will worsen, and the long-term outlook generally is good. Thus, even a low mortality rate is troubling. Once the acute process has resolved, educating the patient and close follow-up are essential.  相似文献   
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