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11.
Abstract : Cyclic nucleotide-gated channels have been proposed to mediate the electrical response to light in the ventral photoreceptor cells of the horseshoe crab, Limulus polyphemus . However, a cyclic nucleotide-gated channel has not been identified from Limulus . We have cloned a putative full-length cyclic nucleotide-gated channel cDNA by screening cDNA libraries constructed from Limulus brain using a probe developed from Limulus ventral eye nerves. The putative full-length cDNA was derived from two overlapping partial cDNA clones. The open reading frame encodes 905 amino acids ; the sequence shows 44% identity to that of the α subunit of the bovine rod cyclic GMP-gated channel over the region containing the transmembrane domains and the cyclic nucleotide binding domain. This Limulus channel has a novel C-terminal region of ~200 amino acids, containing three putative Src homology domain 3 binding motifs and a putative coiled-coil domain. The possibility that this cloned channel is the same as that detected previously in excised patches from the photoreceptive membrane of Limulus ventral photoreceptors is discussed in terms of its sequence and its expression in the ventral eye nerves.  相似文献   
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13.

Background

Base deficit (BD) is commonly used in the operating room (OR) as an endpoint of resuscitation. BD is used as a surrogate marker for the accumulation of lactic acid(Lac). However, the BD can be affected by large amounts of saline.

Methods

We conducted a survey of anesthesiologists regarding the use of BD. We also studied the reliability of BD to determine the presence of hyperlactatemia (HL). Patients undergoing general anesthesia were eligible for enrollment if they were receiving an arterial line as part of their routine care. If an arterial blood gas was drawn by the operative team as part of the routine care, the remainder of the unused blood was also used to measure Lac.

Results

Survey: 73 staff anesthesiologists were surveyed. Over 70% of respondents used BD as an endpoint of resuscitation. Base Deficit Study: 35 patients were enrolled resulting in 88 arterial blood gases with corresponding Lac. Mean age was 61.4 ± 14.3 years, 43% were male. Mean pH was 7.39 ± 0.05, the mean bicarbonate was 23.0 ± 2.3 meq/L, the mean BD 1.34 ± 2.3, and the mean Lac was 1.58 ± 0.71 mmol/L. Mean ASA risk score was 3.16 ± 0.71. ROC area under the curve for base deficit to detect HL was 0.58.

Conclusion

BD can often mislead the clinician as to the actual Lac. Lac can now be measured in the OR in real time. Therefore, if clinicians in the operative setting want to know the Lac, it should be measured directly.  相似文献   
14.
The enzymatic acylation of (RS)-phenylethylamine with different acyl donors catalysed by lipases, was studied in organic solvents with different hydrophobicities and in mixtures with ionic liquids ((ILs); [BMIm][BF4], [BMIm][SCN], [BMIm][Cl] and [BMIm][PF6]). Using lipases from Candida antarctica B (CAL-B) and from Aspergillus niger higher conversion degrees and E-values were obtained with ethyl acetate as the acyl donor. When CAL-B was used as the biocatalyst, in a two-phase system formed by [BMIm][X]/dichloromethane or [BMIm][X]/chloroform, the selectivity was better than that obtained in pure organic solvents. The selectivity was found to be related to individual anions in ILs. In this reaction, the ion effectiveness in enhancing the enzyme selectivity followed the series: Cl > SCN > BF4 > PF6 in mixtures with dichloromethane, and PF6 > BF4 > SCN > Cl in mixtures with chloroform.  相似文献   
15.
Mass culture of benthic macroalgae under rough offshore conditions in the North Sea requires rigid culture support systems that cannot only withstand rough weather conditions but can also be effectively handled while at the same time retain the cultured species. Various carrier constructions and different mooring systems were tested. Laminaria saccharina grew on all of these carriers with initially high (up to 14.5% per day) and later decreasing length increments. Longlines, ladder and grid systems had certain disadvantages and these are discussed. The study results led to a new ring carrier (patent pending), first used in 1994/1995, which was gradually improved until 2002. This system now emerges as being superior, since it resists not only rough weather conditions (2 m s–1 current velocity, 6 m wave height) but also permits ease of handling when compared to other constructions. The ring allows various operational modes and can be equipped with culture lines that can be collected offshore or transported to shore facilities for harvesting. The modular nature of the tested ring system lends itself for future use in integrated aquaculture systems located in or attached to offshore wind farms.  相似文献   
16.
We report the first genome-wide association study of habitual caffeine intake. We included 47,341 individuals of European descent based on five population-based studies within the United States. In a meta-analysis adjusted for age, sex, smoking, and eigenvectors of population variation, two loci achieved genome-wide significance: 7p21 (P = 2.4 × 10(-19)), near AHR, and 15q24 (P = 5.2 × 10(-14)), between CYP1A1 and CYP1A2. Both the AHR and CYP1A2 genes are biologically plausible candidates as CYP1A2 metabolizes caffeine and AHR regulates CYP1A2.  相似文献   
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19.

Background

Biological invasions are a major cause of global species change. Nevertheless, knowledge about the distribution and ecology of introduced species is regionally biased, and many gaps in knowledge exist for most developing countries.

Methodology/Principal Findings

To study the zoobenthos on the hard substratum of the Ilha Grande Bay, a survey was conducted on both natural and artificial substrata at three depths and seven sites. The species recorded were classified as native, cryptogenic or introduced. Multivariate analyses were conducted to assess the prevalence of introduced species in these communities and to compare the distribution of species on natural and artificial substrata of this bay to identify possible discrepancies in habitat use. Of the 61 species, 25 were cryptogenic, 10 were introduced and 26 were native. Similar numbers of introduced species were found on both natural and artificial substrata, though the community composition was significantly different between them. We also compared the species composition of the Ilha Grande Bay survey to other inventories taken around the world. The highest similarities were found between the Ilha Grande Bay inventory and the Atlantic coastal region (Tampa Bay, USA and the Gulf of Mexico), American Samoa and Pearl Harbor (USA) inventories.

Conclusions/Significance

This study presents the first published comprehensive list of hard substratum sessile marine invertebrate species in a Brazilian bay. The high percentage of cryptogenic species reveals gaps in both zoological records and information on introduced species for the Brazilian coast. The introduced species successfully colonized different sites in the Ilha Grande Bay, including both natural and artificial substrata. In addition, we find that artificial structures may not be good surrogates for natural rocky shores and may represent an ecological threat. Comparisons with other inventories suggest a history of broad-scale invasion, though more evidence is needed to support this conclusion.  相似文献   
20.
We investigated the effect of 24-epibrassinolide (BR) on the cytokinin-bioassay based on growth of isolated radish ( Raphanus sativus L. cv. Tondo Rosso Quarantino) cotyledons. BR stimulated growth of the cotyledons by about 50% when applied at saturating concentrations (3 μ M ). This effect was much lower than that of saturating concentrations of benzyladenine (BA) which was about 150% at 10 μ M BA. The effects of saturating concentrations of BR and BA were additive. BR, but not BA, stimulated H+-secretion by the cotyledons (measured as acidification of the incubation medium) slightly but reproducibly. These results indicate that the modes of action of the two phytoregulators are at least partially different.
BR-induced stimulation of H+-secretion was of similar amplitude to that induced by a concentration of fusicoccin (30 n M ) such as to stimulate growth to the same extent as BR. These results suggest that BR-induced stimulation of radish cotyledon growth might depend, at least in part, on BR-induced acidification of the wall space, similar to that observed on Azuki bean epicotyls and maize roots.  相似文献   
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