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91.
We have isolated an insertional mutant of Dictyostelium discoideum that aggregated rapidly and formed spores and stalk cells within 14 h of development instead of the normal 24 h. We have shown by parasexual genetics that the insertion is in the rdeA locus and have cloned the gene. It encodes a predicted 28 kDa protein (RdeA) that is enriched in charged residues and is very hydrophilic. Constructs with the DNA for the c-Myc epitope or for the green fluorescent protein indicate that RdeA is not compartmentalized. RdeA displays homology around a histidine residue at amino acid 65 with members of the H2 module family of phosphotransferases that participate in multistep phosphoryl relays. Replacement of this histidine rendered the protein inactive. The mutant is complemented by transformation with the Ypd1 gene of Saccharomyces cerevisiae, itself an H2 module protein. We propose that RdeA is part of a multistep phosphorelay system that modulates the rate of development. 相似文献
92.
VL Beggs SB Willis EL Maislen TM Stokes D White M Sanford A Becker S Barber PC Pawlow C Downs 《Canadian Metallurgical Quarterly》1998,12(4):72-86
Short hospitalizations for patients undergoing coronary artery bypass grafting (CABG) require continuous nursing evaluation of patients' discharge education. Six institutions collaborated in surveying 300 postoperative patients with CABG to identify learning priorities and patients' perceptions of the effectiveness of discharge education. Data analysis from the self-administered questionnaire demonstrated consistent patient priorities across institutions. Differences in teaching methods and content did not affect perceived preparedness or importance scores. Regional experience demonstrates that variable teaching efforts meet patients' priorities and provide high overall patient preparedness for discharge. Patients with the shortest hospitalizations had higher preparedness scores. 相似文献
93.
Both estradiol and nonylphenol (NP) inhibited hepatic microsomal 7-ethoxyresorufin O-deethylase (EROD) activity of beta-naphthoflavone-treated rats. Enzyme kinetic analyses (Lineweaver-Burk plots) using different estradiol and NP concentrations with graded increases in the concentrations of the substrate, ethoxyresorufin, showed that the inhibition was of a competitive nature at all concentrations of estradiol or NP used. Thus, the mechanism by which NP inhibits EROD activity is similar to that of estradiol. NP, however, was much less potent than estradiol. Young rats treated in vivo with 80 mg/kg body weight of NP demonstrated a slight but significant decrease in their hepatic microsomal EROD activity and CYP1A protein as measured by western blot analysis. In addition, treatment with NP led to a decrease in the steady-state levels of hepatic CYP1A mRNA in rats, suggesting that NP acted at the pre-translational level. The competitive nature of inhibition by NP on hepatic microsomal EROD activity indirectly suggests that this compound is a possible substrate of the CYP1A enzyme. Furthermore, NP had a moderate modulating effect on the expression of CYP1A in rat liver. 相似文献
94.
JC Meltzer V Sanders PC Grimm N Chiasson HJ Hoeltke KL Garrett AH Greenberg DM Nance 《Canadian Metallurgical Quarterly》1998,19(8-9):1351-1355
The application of nonradioactive RNA probes for Northern blotting offers the advantage of a rapid turn-around time for results without the loss of sensitivity for target mRNA detection. However, a problem that has impeded the widespread use of nonradioactive RNA probes for use in Northern blotting is the difficulty in stripping these probes from nylon membranes after hybridization. In this report we describe two protocols for stripping digoxigenin (Dig)-labeled RNA probes from nylon membranes. One protocol utilizes a phosphate-buffered formamide stripping solution to remove nonchemically modified (regular) RNA probes while the other method utilizes strippable probes that were produced with a chemically modified nucleotide (CTP) and removed by a specific stripping solution. This latter method was developed by Ambion Inc. and is called Strip-EZ. We also describe a protocol for the detection of two separate rat mRNAs using both biotin and digoxigenin-labeled RNA probes that does not require stripping the membrane after hybridization. Finally, we describe the use of another new labeling technology, called Chem-Link, that quickly and conveniently labels RNA for use in Northern blotting. 相似文献
95.
96.
Fernando Ruiz 《微电脑世界》2012,(11):128-130
随着Android终端设备的快速普及,这个移动互联的大时代,不仅促成了智能设备的如日中天,同时也为罪恶之手打开了一扇全新的大门。Android.FakeInstaller就是这样一个广泛传播的移动恶意软件系列。它曾假冒奥运会赛事成绩应用、Skype、Flash Player、Opera和许多其他流行应用程序。事实上,在移动恶意软件界,FakeInstaller系列是我 相似文献
97.
An opportunity arose in 1985 to become involved in a transition of working practice from hard copy to VDT. Over a two-year period, 161 VDT users and 65 control subjects in the same office environment were regularly and routinely examined for symptoms of asthenopia. The analysis of data shows that there are no significant differences in type, number and frequency of the work-related symptoms between VDT users and non-VDT users. It appears that reporting of symptoms within the group may be random, although certain symptoms do appear more frequently than others. Additionally, it appears that there is a significant difference between male and female users in the frequency of symptom reporting. 相似文献
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100.
Erika Nassar Chris Mulligan Lem Taylor Chad Kerksick Melyn Galbreath Mike Greenwood Richard Kreider Darryn S Willoughby 《Journal of the International Society of Sports Nutrition》2007,4(1):14-13
Melatonin and resistance exercise alone have been shown to increase the levels of growth hormone (GH). The purpose of this
study was to determine the effects of ingestion of a single dose of melatonin and heavy resistance exercise on serum GH, somatostatin
(SST), and other hormones of the GH/insulin-like growth factor 1 (IGF-1) axis. Physically active males (n = 30) and females
(n = 30) were randomly assigned to ingest either a melatonin supplement at 0.5 mg or 5.0 mg, or 1.0 mg of dextrose placebo.
After a baseline blood sample, participants ingested the supplement and underwent blood sampling every 15 min for 60 min,
at which point they underwent a single bout of resistance exercise with the leg press for 7 sets of 7 reps at 85% 1-RM. After
exercise, participants provided additional blood samples every 15 min for a total of 120 min. Serum free GH, SST, IGF-1, IGFBP-1,
and IGFBP-3 were determined with ELISA. Data were evaluated as the peak pre- and post-exercise values subtracted from baseline
and the delta values analyzed with separate three-way ANOVA (p < 0.05). In males, when compared to placebo, 5.0 mg melatonin
caused GH to increase (p = 0.017) and SST to decrease prior to exercise (p = 0.031), whereas both 0.5 and 5.0 mg melatonin
were greater than placebo after exercise (p = 0.045) and less than placebo for SST. No significant differences occurred for
IGF-1; however, males were shown to have higher levels of IGFBP-1 independent of supplementation (p = 0.004). The 5.0 mg melatonin
dose resulted in higher IGFBP-3 in males (p = 0.017). In conclusion, for males 5.0 mg melatonin appears to increase serum
GH while concomitantly lowering SST levels; however, when combined with resistance exercise both melatonin doses positively
impacts GH levels in a manner not entirely dependent on SST. 相似文献