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1.
Russell et al have shown that the compliance of patients can be enhanced by general practitioners'' providing them with written materials.'' We examined what educational materials for patients were used by general practitioners and where the materials came from.  相似文献   
2.
NEW MURID RODENTS FROM THE LATE CENOZOIC OF YUSHE BASIN, SHANXI   总被引:8,自引:8,他引:0  
<正> As scientific collaborators of the Chinese-American joint project "Neogene Rocks and Faunas, Yushe Basin, Shanxi, PRC", the present authors, with William R. Downs, Northern Arizona University, sampled the Yushe microfauna in the fall of 1987 and 1988. The fossil temains were retrieved by surface collection and by wet-sieving bulk quantities of sediment.  相似文献   
3.
Actinomycin D caused the irreversible loss of PBS1 phage infectious centers and PBS1-mediated transductants. The loss of infectious centers occurred only within the first 4 min after the addition of phage to cells. Actinomycin did not inactivate free phage or inhibit phage adsorption. Electron micrographs indicated that phage adsorbed to cells in the presence of actinomycin ejected their deoxyribonucleic acid (DNA) normally. However, when cells were infected in the presence of actinomycin, 15 to 22% of their (32)P-labeled DNA appeared in the medium, whereas only 1.5 to 7.2% of the (32)P-labeled DNA appeared in the medium during normal infection. Neither 8-azaguanine nor chloramphenicol caused a similar loss of PBS1 infectious centers or transductants. Actinomycin also caused the loss of SP10 infectious centers but it had no effect on SP01 or phi29 infections. We conclude that actinomycin causes abortion of PBS1 infection by inhibiting the uptake or retention of phage DNA into host cells. The immunity of SP01 and phi29 infections to actinomycin probably reflects differences in the penetration mechanisms of these phages.  相似文献   
4.
Bacillus subtilis 168 thyA, thyB cells degrade and lose from 20 to 30% of their deoxyribonucleic acid (DNA) in 3.5 hr of exposure to 20 mug of nalidixic acid per ml. Degradation appears to be initiated at the replication point and to proceed sequentially along the chromosome from the most recently synthesized DNA to "older" DNA. Both DNA strands appear to be degraded equally, and essentially all of the products of degradation are soluble in cold acid.  相似文献   
5.
The rapid repolarization during phase 1 of the action potential of sheep cardiac purkinje fibers has been attributed to a time- and voltage-dependent chloride current. In part, this conclusion was based on experiments that showed a substantial slowing of phase 1 when larger, presumably impermeant, anions were substituted for chloride in tyrode’s solution. We have re- examined the electrical effects of low-chloride solutions. We recorded action potentials of sheep cardiac purkinje fibers in normal tyrode’s solution and in low-chloride solutions made by substituting sodium propionate, acetylglycinate, methylsulfate, or methanesulfonate for the NaCl of Tyrode’s solution. Total calcium was adjusted to keep calcium ion activity of test solutions equal to that of control solutions. Propionate gave qualitatively variable results in preliminary experiments; it was not tested further. Low-chloride solutions made with the other anions gave much more consistent results: phase 1 and the notch that often occurs between phases 1 and 2 were usually unaffected, and the action potential duration usually increased. The only apparent change in the resting potential was a transient 3-6 mV depolarization when low-chloride solution was first admitted to the chamber, and a symmetrical transient hyperpolarization when chloride was returned to normal. If a time- and voltage-dependent chloride current exists in sheep cardiac purkinje fibers, our results suggest that it plays little role in generating phase 1 of the action potential.  相似文献   
6.
The rabbit geneLpq, which codes for a low-density serum lipoprotein2, is linked (34.6 ± 5.3 centimorgans) to the Ig kappa light-chain gene (Ab). There is no evidence thatLpq is linked to another gene,Prt, that was previously found to be linked to theAb gene. This suggests that the gene order for the three genes isPrt- Ab- Lpq. Abbreviations used in this paper Ig immunoglobulin - a the heavy-chain variable-region geneAa - b the kappa light-chain geneAb - q the low-density serum lipoprotein geneLpq  相似文献   
7.
8.

Background  

Text-mining can assist biomedical researchers in reducing information overload by extracting useful knowledge from large collections of text. We developed a novel text-mining method based on analyzing the network structure created by symbol co-occurrences as a way to extend the capabilities of knowledge extraction. The method was applied to the task of automatic gene and protein name synonym extraction.  相似文献   
9.
BACKGROUND: Biochemical testing for pheochromocytoma by measurement of fractionated plasma metanephrines is limited by false positive rates of up to 18% in people without known genetic predisposition to the disease. The plasma normetanephrine fraction is responsible for most false positives and plasma normetanephrine increases with age. The objective of this study was to determine if we could improve the specificity of fractionated plasma measurements, by statistically adjusting for age. METHODS: An age-adjusted metanephrine score was derived using logistic regression from 343 subjects (including 33 people with pheochromocytoma) who underwent fractionated plasma metanephrine measurements as part of investigations for suspected pheochromocytoma at Mayo Clinic Rochester (derivation set). The performance of the age-adjusted score was validated in a dataset of 158 subjects (including patients 23 with pheochromocytoma) that underwent measurements of fractionated plasma metanephrines at Mayo Clinic the following year (validation dataset). None of the participants in the validation dataset had known genetic predisposition to pheochromocytoma. RESULTS: The sensitivity of the age-adjusted metanephrine score was the same as that of traditional interpretation of fractionated plasma metanephrine measurements, yielding a sensitivity of 100% (23/23, 95% confidence interval [CI] 85.7%, 100%). However, the false positive rate with traditional interpretation of fractionated plasma metanephrine measurements was 16.3% (22/135, 95% CI, 11.0%, 23.4%) and that of the age-adjusted score was significantly lower at 3.0% (4/135, 95% CI, 1.2%, 7.4%) (p < 0.001 using McNemar's test). CONCLUSION: An adjustment for age in the interpretation of results of fractionated plasma metanephrines may significantly decrease false positives when using this test to exclude sporadic pheochromocytoma. Such improvements in false positive rate may result in savings of expenditures related to confirmatory imaging.  相似文献   
10.
The purpose was to assess whether body cooling between 2 bouts of exercise in the heat enhances performance during the second exercise session. Using a random, crossover design, 15 subjects (3 women, 12 men; 28 +/- 2 years, 180 +/- 2 cm, 69 +/- 2.3 kg) participated in all 3 trials. Subjects ran 90 minutes on hilly trails in a hot environment (approximately 27 degrees C) before 12 minutes of either cold water immersion (CWI; 13.98 degrees C), ice water immersion (IWI; 5.23 degrees C), or a mock treatment (MT) of sitting in a tub with no water (29.50 degrees C). After immersion, subjects ran a 2-mile race. CWI had faster (p < 0.05) performance time (725 seconds) than MT (769 seconds). CWI and IWI had significantly (p < 0.05) lower rectal temperatures postimmersion than MT as well as postrace (p < 0.05). Heart rate also remained significantly lower (p < 0.05) during the CWI and IWI trials for the first half of the race. In conclusion, CWI enhances performance (6% improvement in race time) in the second bout of exercise, supporting its potential role as an ergogenic aid in athletic performance.  相似文献   
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