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1.
An in vitro photoautotrophic step based on the supply of CO2-enriched air (1,600 μmol mol?1) during the light phase and ambient air (350 μmol mol?1 CO2) during the dark phase has been used to promote the ex vitro establishment of coconut (Cocos nucifera L.) seedlings. The introduction of this step into a previously developed in vitro protocol was found to improve the quality of the seedlings (as assessed by fresh weight increase, physical stature, leaf area and thickness, stomatal density, and chlorophyll a content, and primary and secondary root production), the proportion of seedlings successfully transferred to soil (improvement from 40% to 100%) and achieved in a shorter time (reduction from 10 to 6 mo). Best results using this photoautotrophic growth step were obtained when a low medium concentration of sucrose (43.8 mM or lower) was used, when it was applied to seedlings that had already reached 4 or 5 mo of age in the in vitro culture step, and when seedlings were cultured in the photoautotrophic system for 2 mo or more before transfer to soil. Our improved protocol is more efficient and it reduces the cost per plant for the international exchange of coconut germplasm.  相似文献   
2.
Plant Molecular Biology Reporter - Apiculus color of grain is an important trait which is used as a morphological marker in rice (Oryza sativa. L). In the present study, the purple apiculus mutant...  相似文献   
3.
Several 3-alkylphenols including 3-undecylphenol, which was isolated from a Sumatran rainforest plant, were synthesized to investigate their antinematodal activity against the phytopathogenic nematodes, Bursapherencus xylophilus. A three-step synthesis involving the treatment of 2-cyclohexen-1-one with the Grignard reagent, oxidation of the resulting 1-alkyl-2-cyclohexen-1-ol and subsequent aromatization of 3-alkyl-2-cyclohexen-1-one successfully afforded such phenols. Among the 3-alkylphenols, 3-nonylphenol showed the highest activity, while 3-decylphenol and 3-undecylphenol also showed high activity.  相似文献   
4.
The antiviral efficacy of interferons (IFNs) was evaluated using a vaccinia intranasal infection model in mice in this study. We provide evidence that intranasal administration of IFN-alpha and IFN-gamma (days -1 to +3) resulted in 100 and 90% survival against a lethal respiratory vaccinia infection (8 LD50) in mice, respectively; whereas no animals in the placebo group survived through the study period (21 days). The IFN treatment consisted of a single daily dose of 5x10(3) U per mouse for 5 consecutive days. The efficacy of IFN-gamma was evident even when the IFN-gamma treatments started 1-2 days after infection and when a lower dose (2x10(3) U per mouse) was used. The treatment of IFN-alpha and IFN-gamma reduced the virus titers in the lungs of infected mice by 1000-10,000-fold, when the administration started 1 day after infection. Our data suggest that IFN-alpha and IFN-gamma are effective in protecting vaccinia-infected mice from viral replication in lungs and mortality, and may be beneficial in other human orthopoxvirus infections.  相似文献   
5.
Purine antimetabolites have been very successful therapeutic agents against a host of infectious diseases and malignancies. Success of the treatment relies as much on the efficient accumulation by the target cell or organism as it does on selective action on a vital biochemical pathway of the target cell. Here we compare the ability of a new class of tricyclic purine antimetabolites to interact with transporters from human erythrocytes or Trypanosoma brucei. We show that these compounds display a remarkable selectivity for the parasite's transporters. The adenine analogue showed greater trypanocidal activity than the hypoxanthine or guanine analogues in vitro.  相似文献   
6.
Hagos Y  Bahn A  Asif AR  Krick W  Sendler M  Burckhardt G 《Biochimie》2002,84(12):29-1224
A pig kidney cDNA library was screened for the porcine ortholog of the multispecific organic anion transporter 1 (pOAT1). Several positive clones were isolated resulting in two alternatively spliced cDNA clones of pOAT1 (pOAT1 and pOAT1A). pOAT1-cDNAs consist of 2126 or 1895 base pairs (EMBL Acc. No. AJ308234 and AJ308235) encoding 547 or 533 amino acid residue proteins with 89, 87, 83 and 81% homology to the human, rabbit, rat, and mouse OAT1, respectively. Heterologous expression of pOAT1 in Xenopus laevis oocytes revealed an apparent K(m) for [3H]PAH of 3.75 +/- 1.6 microM. [3H]PAH uptake mediated by pOAT1 was abolished by 0.5 mM glutarate or 1 mM probenecid. Functional characterization of pOAT1A did not show any affinity for [3H]PAH. In summary, we cloned two alternative splice variants of the pig ortholog of organic anion transporter 1. One splice form (pOAT1) showed typical functional characteristics of organic anion transporter 1, whereas the second form appears not to transport PAH.  相似文献   
7.
A series of shape-modified flexible nucleosides ('fleximers', 1, 2, and 3) was modeled, synthesized and subsequently assayed against S-adenosyl-L-homocysteine hydrolase (SAHase). No inhibitory activity was observed for the adenosine fleximer, which served as a substrate, but moderate inhibitory activity was exhibited by the guanosine fleximers. This is the first known report of a guanosine nucleoside analogue possessing activity against SAHase.  相似文献   
8.

Background and Aims

Proton pump inhibitors (PPIs) have been associated with adverse clinical outcomes amongst clopidogrel users after an acute coronary syndrome. Recent pre-clinical results suggest that this risk might extend to subjects without any prior history of cardiovascular disease. We explore this potential risk in the general population via data-mining approaches.

Methods

Using a novel approach for mining clinical data for pharmacovigilance, we queried over 16 million clinical documents on 2.9 million individuals to examine whether PPI usage was associated with cardiovascular risk in the general population.

Results

In multiple data sources, we found gastroesophageal reflux disease (GERD) patients exposed to PPIs to have a 1.16 fold increased association (95% CI 1.09–1.24) with myocardial infarction (MI). Survival analysis in a prospective cohort found a two-fold (HR = 2.00; 95% CI 1.07–3.78; P = 0.031) increase in association with cardiovascular mortality. We found that this association exists regardless of clopidogrel use. We also found that H2 blockers, an alternate treatment for GERD, were not associated with increased cardiovascular risk; had they been in place, such pharmacovigilance algorithms could have flagged this risk as early as the year 2000.

Conclusions

Consistent with our pre-clinical findings that PPIs may adversely impact vascular function, our data-mining study supports the association of PPI exposure with risk for MI in the general population. These data provide an example of how a combination of experimental studies and data-mining approaches can be applied to prioritize drug safety signals for further investigation.  相似文献   
9.

Background

Maternal mortality continues to have devastating impacts in many societies, where it constitutes a leading cause of death, and thus remains a core issue in international development. Nevertheless, individual determinants of maternal mortality are often unclear and subject to local variation. This study aims to characterise individual risk factors for maternal mortality in Tigray, Ethiopia.

Methods

A community-based case-control study was conducted, with 62 cases and 248 controls from six randomly-selected rural districts. All maternal deaths between May 2012 and September 2013 were recruited as cases and a random sample of mothers who delivered in the same communities within the same time period were taken as controls. Multiple logistic regression was used to identify independent determinants of maternal mortality.

Results

Four independent individual risk factors, significantly associated with maternal death, emerged. Women who were not members of the voluntary Women’s Development Army were more likely to experience maternal death (OR 2.07, 95% CI 1.04–4.11), as were women whose husbands or partners had below-median scores for involvement during pregnancy (OR 2.19, 95% CI 1.14–4.18). Women with a pre-existing history of other illness were also at increased risk (OR 5.58, 95% CI 2.17–14.30), as were those who had never used contraceptives (OR 2.58, 95% CI 1.37–4.85). Previous pregnancy complications, a below-median number of antenatal care visits and a woman’s lack of involvement in health care decision making were significant bivariable risks that were not significant in the multivariable model.

Conclusions

The findings suggest that interventions aimed at reducing maternal mortality need to focus on encouraging membership of the Women’s Development Army, enhancing husbands’ involvement in maternal health services, improving linkages between maternity care and other disease-specific programmes and ensuring that women with previous illnesses or non-users of contraceptive services are identified and followed-up as being at increased risk during pregnancy and childbirth.  相似文献   
10.
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