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1.
Bombesin-like immunoreactivity (BLI) was detected by a specific radioimmunoassay in extracts of 15 human lungs from fetuses, neonates, infants and children. A higher concentration of lung BLI was found in the fetal/neonatal group (2053.2 ± 316.3 ng bombesin/g protein, n=6) compared to the infant/children group (416.3 ± 64.3 ng/g, n=9). The peaking of BLI in lungs during the fetal/neonatal period suggests an important function for this peptide in intrauterine life and neonatal adaptation. 相似文献
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A wide-ranging examination of plastid (pt)DNA sequence homologies within
higher plant nuclear genomes (promiscuous DNA) was undertaken. Digestion
with methylation-sensitive restriction enzymes and Southern analysis was
used to distinguish plastid and nuclear DNA in order to assess the extent
of variability of promiscuous sequences within and between plant species.
Some species, such as Gossypium hirsutum (cotton), Nicotiana tabacum
(tobacco), and Chenopodium quinoa, showed homogenity of these sequences,
while intraspecific sequence variation was observed among different
cultivars of Pisum sativum (pea), Hordeum vulgare (barley), and Triticum
aestivum (wheat). Hypervariability of plastid sequence homologies was
identified in the nuclear genomes of Spinacea oleracea (spinach) and Beta
vulgaris (beet), in which individual plants were shown to possess a unique
spectrum of nuclear sequences with ptDNA homology. This hypervariability
apparently extended to somatic variation in B. vulgaris. No sequences with
ptDNA homology were identified by this method in the nuclear genome of
Arabidopsis thaliana.
相似文献
4.
A survey was conducted to determine the levels of fumonisins B1 and B2 in corn and corn-based products available in Colombia
for human and animal consumption. A total of 120 samples were analyzed by acetonitrile-water extraction, cleanup with a strong-anion-exchange
column, and liquid chromatography with o-phthaldialdehyde-2-mercaptoethanol derivatization and fluorescence detection. The
samples of corn and corn-based products for animal intake were taken at different feed manufacturing plants, whereas the samples
used for human foods where purchased from local retail stores. The number of positive samples for fumonisin B1 was 20.0% higher
in corn and corn-based products for animal intake (75.0%) than in corn and corn-based products for human consumption (55.0%).
The levels of fumonisin B1 were also higher in corn and corn-based products for animal intake (mean = 694 μg/kg; range = 32–2964
μg/kg), than in corn and corn-based products for human intake (mean = 218 μg/kg; range = 24–2170 μg/ kg). The incidence and
levels of fumonisin B2 were lower than those for fumonisin B1. Corn and corn-based products for animal consumption had an
incidence of fumonisin B2 of 58.3%, with a mean value of 283 μg/kg, and a range of 44–987 μg/kg. The incidence of fumonisin
B2 in corn-based products for human intake was 35.0%, with a mean value of 118 μg/kg and a range of 21–833 μg/kg. The highest
incidence and levels of fumonisins were found in samples of hominy feed, with concentrations ranging from 86 to 2964 μg/kg
fumonisin B1 and 57 to 987 μg/kg fumonisin B2. 相似文献
5.
Background:
A hip fracture causes bleeding, pain and immobility, and initiates inflammatory, hypercoagulable, catabolic and stress states. Accelerated surgery may improve outcomes by reducing the duration of these states and immobility. We undertook a pilot trial to determine the feasibility of a trial comparing accelerated care (i.e., rapid medical clearance and surgery) and standard care among patients with a hip fracture.Methods:
Patients aged 45 years or older who, during weekday, daytime working hours, received a diagnosis of a hip fracture requiring surgery were randomly assigned to receive accelerated or standard care. Our feasibility outcomes included the proportion of eligible patients randomly assigned, completeness of follow-up and timelines of accelerated surgery. The main clinical outcome, assessed by data collectors and adjudicators who were unaware of study group allocations, was a major perioperative complication (i.e., a composite of death, preoperative myocardial infarction, myocardial injury after noncardiac surgery, pulmonary embolism, pneumonia, stroke, and life-threatening or major bleeding) within 30 days of randomization.Results:
Of patients eligible for inclusion, 80% consented and were randomly assigned to groups (30 to accelerated care and 30 to standard care) at 2 centres in Canada and 1 centre in India. All patients completed 30-day follow-up. The median time from diagnosis to surgery was 6.0 hours in the accelerated care group and 24.2 hours in the standard care group (p < 0.001). A major perioperative complication occurred in 9 (30%) of the patients in the accelerated care group and 14 (47%) of the patients in the standard care group (hazard ratio 0.60, 95% confidence interval 0.26–1.39).Interpretation:
These results show the feasibility of a trial comparing accelerated and standard care among patients with hip fracture and support a definitive trial. Trial registration: ClinicalTrials.gov, no. .Annually in North America, 0.8% of women and 0.4% of men aged 65 years or older experience a hip fracture. NCT013443431 Patients who sustain a hip fracture face a high risk of serious complications (i.e., cardiovascular, venous thrombotic, infectious and hemorrhagic)2,3 that can result in a prolonged hospital stay and death: 30-day mortality is 9% among men and 5% among women.1 Among surviving patients who were community-dwelling before their fracture, 11% become bed-ridden and 16% are admitted to a long-term care facility.4A hip fracture results in pain, bleeding and immobility. These factors initiate inflammatory, hypercoagulable, catabolic and stress states that can precipitate medical complications.5–11 Early surgery shortens the exposure to these harmful states and, therefore, may reduce morbidity and mortality. Furthermore, earlier surgery may shorten the period of immobility, which may improve functional outcomes and reduce costs.A meta-analysis of observational studies evaluating the timing of surgery for a hip fracture included 5 studies (involving 4208 patients and 721 deaths) that reported the adjusted risk of mortality.12 Earlier surgery, irrespective of the cut-off for delay (24, 48 or 72 h), was associated with significantly lower mortality (adjusted relative risk 0.81, 95% confidence interval [CI] 0.68–0.96, p = 0.01). Although these data are encouraging, the apparent benefit may be a result of residual confounding (e.g., sicker patients may have had surgery delayed for medical optimization, which may not have been adequately adjusted for in the analyses). Conversely, the real potential of early surgery may be underestimated because the greatest impact may occur when a hip fracture is treated much more quickly than the timelines assessed in the observational studies (24, 48 or 72 h), similar to how treatment of an acute myocardial infarction or stroke within hours has the most dramatic impact.13,14In many countries, including Canada, most patients with a hip fracture wait longer than 24 hours to undergo surgery. The 2 main reasons for delay are preoperative medical clearance and operating room access,15–21 both of which are potentially modifiable. We undertook a pilot trial to determine the feasibility (as assessed by the proportion of eligible patients randomly assigned, completeness of follow-up and timeliness of accelerated surgery) of a large randomized controlled trial (RCT) comparing accelerated care and standard care among adults with a hip fracture. 相似文献6.
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Evolutionary aspects of the gastrointestinal hormones 总被引:1,自引:0,他引:1
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