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1.
Three endocyclic sulfoximides of the 1-aryl- and 1-alkyl-3-oxo-benzo[d]-isothia (IV)-azole 1-oxide type (1-substituent = 2′-carboxyphenyl, 2′-carbethoxyphenyl, and octyl, respectively) were found to be well resolved on a chiral phase derived from bovine serum albumin (BSA). Selectivities (α) of 1.74, 1.12, and 1.44, respectively, were obtained. The retention behaviour of 1-octyl-3-oxo-benzo[d]isothia(IV)-azole 1-oxide was further investigated in some detail as a function of the mobile phase composition and the elution order was established from optically active material obtained from the enantiopure sulfoxide precursor. An enantiomeric excess of 85.4% was obtained in the cyclocondensation reaction of the octyl-substituted sulfoxide precursor with hydrazoic acid to the corresponding endocyclic sulfoximide. © 1995 Wiley-Liss, Inc.  相似文献   
2.
Phenological variations of the marine copepod Calanus finmarchicus were studied in Svalbard and northern Iceland, where samples were collected in summer and spring, respectively, over two decades. Four phenological indices, developed for copepodite stage-structured data, were used: the proportion of CV to total abundance (CVT), the population development index (PDI), the average weighted stage (AWS), and the average age in days (AAD). The variation of these indices was compared within and between locations to evaluate their suitability for the analysis of phenological effects. For both populations, phenology was related to local temperature and spring bloom dynamics, influenced by Atlantic water inflow. Large-scale climate was related to phenological variation only in the Svalbard population. C. finmarchicus phenology advanced under warmer conditions in both locations. We conclude that vertical phenological indices, i.e. based on interannual changes in copepodite stage structure, are useful to investigate zooplankton phenology, especially when data series covering the whole life cycle are unavailable. We suggest that AWS and AAD can be applied irrespective of sampling time, while PDI and CVT should be applied for early and late sampling seasons, respectively. When multiple phenological indices are needed, AAD in combination with either CVT or PDI should be preferred.  相似文献   
3.
The small, sub-ice copepod Jaschnovia brevis is rich in triacylglycerols, suggesting a feeding behaviour not constrained to the seasonal phytoplankton bloom. The copepod's triacylglycerol reserves contain: the diatom biomarkers 16:1n-7 (23.9%), 20:5n-3 (8.5%) and C16 PUFA (1.3%), the flagellate biomarkers 18:4n-3 (3.7%) and 22:6n-3 (3.3%), and the Calanus copepod biomarkers 20:1n-9 (7.7%) and 22:1n-11 (6.2%). Total lipid from particulates in the water column contained polar lipid (45.0%), wax esters (24.9%) and triacylglycerols (11.2%) as major components. The total lipids in the particulates were rich in 18:1n-9 (31.5%) and 16:0 (21.2%), and relatively rich in 18:0 (7.8%) and 18:2n-6 (9.2%). The triacylglycerols in the particulates contained 16:1n-7 (20.7%), C16 PUFA (4.1%), 18:4n-3 (1.9%), 20:5n-3 (3.6%), 22:6n-3 (1.9%), 20:1n-9 (5.2%) and 22:1n-11 (3.9%). The polar lipids in the particulates contained 16:1n-7 (17.3%), C16 PUFA (7.8%), 18:4n-3 (3.3%), 20:5n-3 (14.5%) and 22:6n-3 (9.6%). The fatty alcohols in the wax esters of the particulates were mainly 16:0 (11.3%), 20:1n-9 (21.1%) and 22:1n-11 (30.6%). The nature of the particulates, their possible origin in living and non-living material, and their role in the nutrition of J. brevis are discussed.  相似文献   
4.
5.
Hippocampal neurons responding to first-time dislocation of a target object   总被引:4,自引:0,他引:4  
Fyhn M  Molden S  Hollup S  Moser MB  Moser E 《Neuron》2002,35(3):555-566
To examine how hippocampal neurons respond to a mismatch between retrieved and actual experience, we trained rats to find a hidden platform at a particular location in an annular watermaze and then moved the platform. Several cells that were silent at the new platform location before the move fired vigorously when the rat found the goal. The new activity was paralleled by reduced discharge in a subset of simultaneously recorded interneurons. The pattern of activity returned toward its original configuration as the rat learned the new location. The activation of specific hippocampal neurons following dislocation of a target object may be essential for synaptic plasticity and adaptive modification of the animal's representation of the environment.  相似文献   
6.

Background

In 1988, a cardiovascular prevention program which combined an individual and a population-based strategy was launched within primary health-care in Sollentuna, a municipality in Stockholm County. The aim of this study was to investigate time trends in the incidence of and mortality from acute myocardial infarction and all-cause mortality in Sollentuna compared with the rest of Stockholm County during a period of two decades following the implementation of a cardiovascular prevention program.

Materials and Methods

The average population in Sollentuna was 56,589 (49% men) and in Stockholm County (Sollentuna included) 1,795,504 (49% men) during the study period of 1987–2010. Cases of hospitalized acute myocardial infarction and death were obtained for the population of Sollentuna and the rest of Stockholm County using national registries of hospital discharges and deaths. Acute myocardial infarction incidence and mortality were estimated using the average population of Sollentuna and Stockholm in 1987–2010.

Results

During the observation period, the incidence of acute myocardial infarction decreased more in Sollentuna compared with the rest of Stockholm County in women (-22% vs. -7%; for difference in slope <0.05). There was a trend towards a greater decline in Sollentuna compared to the rest of Stockholm County in the incidence of acute myocardial infarction (in men), acute myocardial mortality, and all-cause mortality but the differences were not significant.

Conclusion

During a period of steep decline in acute myocardial infarction incidence and mortality in Stockholm County the municipality of Sollentuna showed a stronger trend in women possibly compatible with favorable influence of a cardiovascular prevention program.

Trial Registration

ClinicalTrials.gov NCT02212145  相似文献   
7.
The International Journal of Life Cycle Assessment - Environmental product declarations (EPDs) are standardized tools based on life cycle assessment (LCA) to communicate and compare environmental...  相似文献   
8.
Stage IV and V copepodites were the dominant forms of Calanus finmarchicus, C. glacialis and C. hyperboreus in Kongsfjorden in late September 1997. Stage IV and V copepodites of C. glacialis and C. hyperboreus were rich in lipid, largely wax esters, and were well fitted to overwinter. Stage IV copepodites of C. finmarchicus were also rich in wax esters, but stage V copepodites of C. finmarchicus were less wax ester-rich. Large size increments between stage IV and V copepodites and between stage V copepodites and females were noted in C. finmarchicus. A very large increment between stage IV and V copepodites was noted for C. glacialis but the size difference between stage V copepodites and females was very small in this species. Particularly large increments were noted between stage IV and V copepodites of C. hyperboreus and also between stage V copepodites and females of this species. The very large, wax ester-rich C. hyperboreus is well adapted to survive the most extreme variations in the Arctic, in Arctic basin waters, whereas the smaller, wax ester-rich C. glacialis is adapted to survive less extreme Arctic variations, as in Arctic shelf waters. The smallest of the three, C. finmarchicus, is best adapted to survive the more predictable waters of the North Atlantic and the Barents Sea. Accepted: 3 January 2000  相似文献   
9.
Blooms of domoic acid (DA) producing Pseudo-nitzschia, regularly occur off the coast of California. Although it has been hypothesized that these blooms are increasing in frequency, the lack of historical records limits our understanding of potential causal mechanisms. In this study, an 15-year time-series (1993–2008) of sediment trap samples collected from the Santa Barbara Basin (SBB) at 540 m were analyzed for Pseudo-nitzschia (n = 196, microscopy and SEM) and DA (n = 206, LC–MS/MS) concentrations and fluxes. Results suggest that there was an abrupt shift towards greater frequency and higher magnitude Pseudo-nitzschia blooms and toxic DA flux events in the SBB after the year 2000. SEM analysis of sediment trap material indicates that these events were mainly blooms of P. australis, with cell fluxes increasing by an order of magnitude from a maximum of 4.5 × 106 cells m−2 d−1 pre-2000, to as high as 3.2 × 108 cells m−2 d−1 thereafter. Similarly, sediment trap DA fluxes increased by an average of 13.4 μg m−2 d−1, with only one large event (>5 μg m−2 d−1) from 1993 to 1999 versus 16 large DA events from 2000 to 2008. While the causes of this abrupt shift remain ambiguous, we suggest that this shift may be related to natural climate variability associated with a change in phase of the North Pacific Gyre Oscillation (NPGO) and its potential influence on the composition and magnitude of waters that are upwelled into the SBB.  相似文献   
10.

Background

Contributors to long-term mortality in patients with community-acquired pneumonia (CAP) remain unclear, with little attention paid to pneumonia etiology. We examined long-term survival, causes of death, and risk factors for long-term mortality in adult patients who had been hospitalized for CAP, with emphasis on demographic, clinical, laboratory, and microbiological characteristics.

Methods

Two hundred and sixty-seven consecutive patients admitted in 2008–2011 to a general hospital with CAP were prospectively recruited and followed up. Patients who died during hospital stay were excluded. Demographic, clinical, and laboratory data were collected within 48 hours of admission. Extensive microbiological work-up was performed to establish the etiology of CAP in 63% of patients. Mortality data were obtained from the Norwegian Cause of Death Registry. Cox regression models were used to identify independent risk factors for all-cause mortality.

Results

Of 259 hospital survivors of CAP (median age 66 years), 79 (30.5%) died over a median of 1,804 days (range 1–2,520 days). Cumulative 5-year survival rate was 72.9% (95% CI 67.4–78.4%). Standardized mortality ratio was 2.90 for men and 2.05 for women. The main causes of death were chronic obstructive pulmonary disease (COPD), vascular diseases, and malignancy. Independent risk factors for death were the following (hazard ratio, 95% CI): age (1.83 per decade, 1.47–2.28), cardiovascular disease (2.63, 1.61–4.32), COPD (2.09, 1.27–3.45), immunocompromization (1.98, 1.17–3.37), and low serum albumin level at admission (0.75 per 5g/L higher, 0.58–0.96), whereas active smoking was protective (0.32, 0.14–0.74); active smokers were younger than non-smokers (P < 0.001). Microbial etiology did not predict mortality.

Conclusions

Results largely confirm substantial comorbidity-related 5-year mortality after hospitalization for CAP and the impact of several well-known risk factors for death, and extend previous findings on the prognostic value of serum albumin level at hospital admission. Pneumonia etiology had no prognostic value, but this remains to be substantiated by further studies using extensive diagnostic microbiological methods in the identification of causative agents of CAP.  相似文献   
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