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1.
An in vitro method for the establishment and storage of over 200 Saccharum spp. hybrid clones was developed that involved only 1 medium for shoot development and multiplication, and no decontamination procedures. Apical buds, from the leaf axils of developing leaves surrounding the apical meristem, were cultured on medium containing the plant growth regulators 6-benzylaminopurine (BAP) and 6-furfurylaminopurine (kinetin), and regenerated multiple shoots. Shoots transferred to medium containing naphthaleneacetic acid (NAA) developed roots. In vitro plants transferred to a medium containing half strength salts and vitamins without plant growth regulators were placed in storage at 18°C. After 12 months of storage plants were transferred to fresh medium and returned to storage. The genetic integrity of clones (based on phenotype assessment) was not affected by the in vitro culture method and up to 14 months of low-maintenance storage conditions. These in vitro plants will be further tested for genetic stability using biochemical and molecular techniques.  相似文献   
2.
New biomass crop hybrids for bioeconomic expansion require yield projections to determine their potential for strategic land use planning in the face of global challenges. Our biomass growth simulation incorporates radiation interception and conversion efficiency. Models often use leaf area to predict interception which is demanding to determine accurately, so instead we use low-cost rapid light interception measurements using a simple laboratory-made line ceptometer and relate the dynamics of canopy closure to thermal time, and to measurements of biomass. We apply the model to project the European biomass potentials of new market-ready hybrids for 2020–2030. Field measurements are easier to collect, the calibration is seasonally dynamic and reduces influence of weather variation between field sites. The model obtained is conservative, being calibrated by crops of varying establishment and varying maturity on less productive (marginal) land. This results in conservative projections of miscanthus hybrids for 2020–2030 based on 10% land use conversion of the least (productive) grassland and arable for farm diversification, which show a European potential of 80.7–89.7 Mt year−1 biomass, with potential for 1.2–1.3 EJ year−1 energy and 36.3–40.3 Mt year−1 carbon capture, with seeded Miscanthus sacchariflorus × sinensis displaying highest yield potential. Simulated biomass projections must be viewed in light of the field measurements on less productive land with high soil water deficits. We are attempting to model the results from an ambitious and novel project combining new hybrids across Europe with agronomy which has not been perfected on less productive sites. Nevertheless, at the time of energy sourcing issues, seed-propagated miscanthus hybrids for the upscaled provision of bioenergy offer an alternative source of renewable energy. If European countries provide incentives for growers to invest, seeded hybrids can improve product availability and biomass yields over the current commercial miscanthus variety.  相似文献   
3.
Cilia are microtubule‐based structures that either transmit information into the cell or move fluid outside of the cell. There are many human diseases that arise from malfunctioning cilia. Although mammalian models provide vital insights into the underlying pathology of these diseases, aquatic organisms such as Xenopus and zebrafish provide valuable tools to help screen and dissect out the underlying causes of these diseases. In this review we focus on recent studies that identify or describe different types of human ciliopathies and outline how aquatic organisms have aided our understanding of these diseases.  相似文献   
4.
The relationship between RNA and DNA oxidation and pharmacological treatment has not been systematically investigated in patients with type 2 diabetes (T2D). We aimed to investigate the association between pharmacological treatments and levels of urinary markers of nucleic acid oxidation in T2D patients. Vejle Diabetes Biobank cohort data was nested into nationwide registry data. Multiple logistic regression was used to associate drug usage with risk of high (above median) RNA and DNA oxidation. Data from 2664 T2D patients (64% male, age range: 25–75) were included. Questionnaire-validated lipid lowering drug use was associated with low RNA oxidation (Odds ratio, OR 0.71, 95% CI: [0.59–0.87]). Insulin and non-specific antidiabetic drugs were associated with low DNA oxidation (insulin: OR 0.60, 95% CI [0.49–0.73]). Oral antidiabetics were associated with high DNA oxidation and RNA oxidation (OR 1.30, 95% CI [1.10–1.53] and OR 1.26, 95% CI [1.07–1.29]). Our findings indicate that diabetes-related drugs are associated with RNA and DNA oxidation and further studies are required to determine causality in T2D patients.  相似文献   
5.
Quantitative (1)H NMR measurements revealed delta(11(13)) sesquiterpene gamma-lactones as the main constituents ( >or= 1% per weight of dried plant material) in the crude extracts of the aerial parts of Amphoricarpos neumayeri ssp. neumayeri and ssp. murbeckii from mountains Orjen and Visitor (Montenegro), respectively. Preparative silica gel chromatography afforded thirteen guai-11(13)-en-12,6alpha-olides, named amphoricarpolides (1-13), with the same relative (1alphaH,4betaH,5alphaH,7betaH) configuration of the basic skeleton. The common structural feature of lactones 2-13 was 3beta,15-dioxygenation pattern. The only exception was 1 (3-deoxyamphoricarpolide), containing a single oxygen substituent (15-OH). Eight of them exhibited an additional oxygen substituent, 9beta-OH (5 and 6), 2alpha-OH (8-12), or 2alpha-OAc (13). Compound 7 was epoxydated at 10alpha(14)-position, whereas the remaining lactones contained a 10(14) double bond.  相似文献   
6.
Thepurpose of this study was to determine the role of p42/p44mitogen-activated protein kinase (MAPK) in1-adrenergically and cholinergically stimulated proteinsecretion in rat lacrimal gland acinar cells and the pathways used bythese agonists to activate MAPK. Acini were isolated by collagenasedigestion and incubated with the 1-adrenergic agonistphenylephrine or the cholinergic agonist carbachol, and activation ofMAPK and protein secretion were then measured. Phenylephrine andcarbachol activated MAPK in a time- and concentration-dependent manner.Inhibition of MAPK significantly increased phenylephrine- andcarbachol-induced protein secretion. Inhibition of EGF receptor (EGFR)with AG1478, an inhibitor of the EGFR tyrosine kinase activity,significantly increased phenylephrine- but not carbachol-inducedprotein secretion. Whereas phenylephrine-induced activation of MAPK wascompletely inhibited by AG1478, activation of MAPK by carbachol wasnot. Phenylephrine stimulated tyrosine phosphorylation of the EGFR, whereas carbachol stimulated p60Src, and possibly Pyk2, toactivate MAPK. We conclude that, in the lacrimal gland, activation ofMAPK plays an inhibitory role in 1-adrenergically andcholinergically stimulated protein secretion and that these agonistsuse different signaling mechanisms to activate MAPK.

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7.
Dukic V  Gatsonis C 《Biometrics》2003,59(4):936-946
Current meta-analytic methods for diagnostic test accuracy are generally applicable to a selection of studies reporting only estimates of sensitivity and specificity, or at most, to studies whose results are reported using an equal number of ordered categories. In this article, we propose a new meta-analytic method to evaluate test accuracy and arrive at a summary receiver operating characteristic (ROC) curve for a collection of studies evaluating diagnostic tests, even when test results are reported in an unequal number of nonnested ordered categories. We discuss both non-Bayesian and Bayesian formulations of the approach. In the Bayesian setting, we propose several ways to construct summary ROC curves and their credible bands. We illustrate our approach with data from a recently published meta-analysis evaluating a single serum progesterone test for diagnosing pregnancy failure.  相似文献   
8.
9.
The chloroplast DNA of 43 species including 16 sections from the genus Hypericum was studied by PCR-RFLP analysis. The PCR-amplified products of four cpDNA regions, trnC-trnD, psbC-trnS, trnL-trnF and rbcL were digested with four restriction endonucleases. A high level of interspecific variation was detected while intraspecific diversity was not observed. The resulting parsimony analysis indicated the monophyletic assemblage of the sections Androsaemum, Olympia, Drosocarpium and Trigynobrathys. Monophyly of Hypericum is weakly supported, but close relationships of H. perforatum and H. maculatum are indicated. The members of Ascyreia are weakly resolved, but clustering of H. kouytchense and H. oblongifolium is well supported, however, H. reptans is nested with Olympia. CpDNA profiles and the positions on the parsimony tree indicate that the chloroplast donor among the putative parents of the hybrid species H. ×inodorum is H. androsaemum.  相似文献   
10.
During hibernation animals oscillate from near ambient (T(a)) to euthermic body temperatures (T(b)). As animals arouse, the rate of rewarming (RRW) might be expected to simply increase as a function of time. We monitored the T(b) of golden-mantled ground squirrels (Spermophilus lateralis) housed at 4, 8, 12, and 16 degrees C during natural arousals. The maximum RRW, the time required to reach a maximum RRW, and the relative time index all demonstrated negative relationships with T(a). The T(b) corresponding to maximal RRW demonstrated a positive relationship with T(a). Squirrels reached maximal RRW when they had generated 30 to 40% of the heat required to reach a euthermic T(b). These data suggest that arousal is more constrained than expected and that both time and temperature influence the RRW.  相似文献   
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