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11.
12.
Demonstration of rubella complement-fixing antigens of two distinct particle sizes by gel filtration on sephadex G-200 总被引:3,自引:0,他引:3
13.
M H Gee J E Gottlieb K H Albertine J M Kubis S P Peters J E Fish 《Journal of applied physiology》1990,69(3):822-829
Thirty-nine patients with adult respiratory distress syndrome (ARDS) were enrolled in a study to identify potential age-related changes in organ system function that may help explain the apparent association between age and poor outcome in these patients. Criteria for enrollment included an arterial PO2-to-inspired O2 concentration ratio less than or equal to 200 in a clinical setting consistent with ARDS. Patients were excluded if they were less than 18 yr old, had clinical manifestations of congestive heart failure, were seropositive for the human immunodeficiency virus, or had stage II metastatic lung cancer. Patients were divided into two groups: those less than 60 yr old (mean 42 +/- 3 yr, n = 17) and those greater than or equal to 60 yr old (73 +/- 2 yr, n = 16). A group of six patients was analyzed as a separate subset based on a body temperature less than or equal to 97.5 degrees F at enrollment (hypothermic patients, 73 +/- 4 yr old). Sepsis was present in 67% of the nonhypothermic patients and in all the hypothermic patients. Mortality rates were 12% in the patients less than 60 yr and 69% in the nonhypothermic patients greater than or equal to 60 yr. All the hypothermic patients died. Sequential data obtained over 6 days were compared within and between groups. The following results were obtained. 1) The ratio of arterial PO2 to inspired O2 fraction was greater and the positive end-expiratory pressure used was significantly less in the patients greater than or equal to 60 yr old compared with the younger group.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
14.
L. E. Talbert N. K. Blake P. W. Chee T. K. Blake G. M. Magyar 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1994,87(7):789-794
The polymerase chain reaction (PCR) is an attractive technique for many genome mapping and characterization projects. One PCR approach which has been evaluated involves the use of randomly amplified polymorphic DNA (RAPD). An alternative to RAPDs is the sequence-tagged-site (STS) approach, whereby PCR primers are designed from mapped low-copy-number sequences. In this study, we sequenced and designed primers from 22 wheat RFLP clones in addition to testing 15 primer sets that had been previously used to amplify DNA sequences in the barley genome. Our results indicated that most of the primers amplified sequences that mapped to the expected chromosomes in wheat. Additionally, 9 of 16 primer sets tested revealed polymorphisms among 20 hexaploid wheat genotypes when PCR products were digested with restriction enzymes. These results suggest that the STS-based PCR analysis will be useful for generation of informative molecular markers in hexaploid wheat.Contribution no. J-2833 of the Montana Agric Exp Stn 相似文献
15.
Paula P. Chee 《Plant cell reports》1995,14(9):560-565
Summary A method is described for multiple shoot and plantlet formation from zygotic embryos of Taxus brevifolia. Adventitious bud primordia were best induced by culturing zygotic embryos on 1/2B5 medium supplemented with 10 M BA for 14 days. Further vegetative buds were produced following subculture to half-strength McCown's basal salt medium containing 1.0% activated charcoal. Individual adventitious shoots were excised and approximately 5% of these formed roots. Rooting frequency was increased to 58% by a single treatment with ABT rooting powder. Vigorous growing Taxus brevifolia plants were established after transfer to plant growth medium. 相似文献
16.
To monitor incubation conditions in nests of greater sandhill cranes, a radiotrans-mitting egg was built using six temperature sensors, a position sensor, and a light sensor. Sensor readings were received, along with time of observations, and stored in a computer. The egg was used to monitor incubation in nests of six pairs of cranes during 1987 and 1988. Ambient temperature was also measured. Analysis of covariance (ANCOVA) was used to relate highest egg temperature, core egg temperature, and lowest egg temperature to ambient temperature, time since the egg was last turned, and time since the beginning of incubation. Ambient temperature had the greatest effect on egg temperature (P < 0.0001), followed by the time since the beginning of incubation and time since the egg was last turned. Pair effect, the class variable in the ANCOVA, was also very significant (P < 0.0001). A nine-term Fourier series was used to estimate the average core egg temperature versus time of day and was found to fit the data well (r2 = 0.94). The Fourier series will be used to run a mechanical incubator to simulate natural incubation conditions for cranes. © 1995 Wiley-Liss, Inc. 相似文献
17.
18.
The effect of GABA on in vitro binding of two novel non-benzodiazepines, PK 8165 and CGS 8216, to benzodiazepine receptors in the rat brain 总被引:1,自引:0,他引:1
The effect of gamma-aminobutyric acid (GABA) on the binding of PK 8165, a quinoline derivative, and CGS 8216, a pyrazoloquinoline, was assessed in two different regions of the rat brain. PK 8165, a compound with reported anxiolytic properties, inhibited [3H]-propyl beta-carboline-3-carboxylate labeled receptors in the cerebellum with an IC50 of 844 nM and 370 nM in the absence and presence of micro M GABA, respectively. GABA (100 micro M) was less effective in the cerebral cortex, decreasing the IC50 value from 280 to 197 nM. In saturation isotherm studies with [3H]-CGS 8216, a benzodiazepine receptor antagonist, GABA (100 micro M) induced a small but significant reduction in the apparent affinity of [3H]-CGS 8216 for benzodiazepine receptors in the cerebral cortex but the Bmax was unchanged. 相似文献
19.
The novel pyrazoloquinoline, CGS, 9896, was a potent inhibitor of specific [3H]-flunitrazepam binding in several brain regions with subnanomolar KI values. The inhibition of [3H] propyl beta-carboline-3-carboxylate ([3H]-PCC-) binding by CGS 9896 was enhanced by gamma-aminobutyric acid (GABA) but not by chloride ion. GABA enhancement of CGS 9896 inhibition of [3H]-PCC binding predicts this compound has benzodiazepine (BZD) agonist-type activity. Behavioral studies support this prediction. CGS 9896 was found to protect mice against bicuculline and metrazol induced seizure at doses that did not induce ataxia or sedation. CGS 9896 may represent a class of compounds with potential therapeutic value. The high affinity of this non-BZD compound suggests that CGS 9896 may also be of value as a high affinity ligand for the continued study of BZD receptors. 相似文献
20.
Closed needle liver biopsy routinely provides 60-100 mg tissue from rhesus monkeys (Macaca mulatta). No mortality or morbidity was observed in over 400 needle biopsies during a two-year period in which some monkeys were biopsied over 30 times. Biopsy tissue was used as enzyme source in low-volume in vitro systems for measurement of hepatic monooxygenase activity. 相似文献