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41.
Purpose: Circulating chromogranin B (CgB) levels are increased in situations characterized by systemic and myocardial stress, but whether CgB provides prognostic information in patients with acute respiratory failure (ARF) is unknown.

Methods: We included 584 patients with ARF, defined as ventilatory support?>6?h, and with blood samples available on Intensive Care Unit (ICU) admission and day 3 (n?=?479). CgB levels were measured by radioimmunoassay and follow-up was 90 days.

Results: One-hundred-sixty-nine patients (29%) died during follow-up. Admission CgB levels separated non-survivors from survivors: median 1234 (Q1-3 989–1742) vs. 917 (753–1224) pmol/L, respectively, p?<?0.001. CgB levels on ICU admission (logarithmically transformed) were associated with time to death after adjustment for established risk indices available on ICU admission, including N-terminal pro-B-type natriuretic levels: HR 2.62 (95%C.I. 1.82–3.77), p?<?0.001. Admission CgB levels also improved prognostication on top of SOFA and SAPS II scores as assessed by Cox regression analyses and the category-free net reclassification index. The area under the curve (AUC) for admission CgB levels to separate survivors and non-survivors was 0.72 (95%CI 0.67–0.76), while the AUC on day 3 was 0.60 (0.54–0.66).

Conclusions: CgB levels measured on ICU admission provided additional prognostic information to established risk indices in ARF patients.  相似文献   

42.
The role of microtubules (MTs) in vegetative nucleus (VN) and generative cell (GC) transport was investigated by comparing VN and GC distribution with callose plug formation in tobacco pollen grains germinated and grown for 12 h with the plant-specific anti-MT drug oryzalin. The VN-GC complex or VN alone was located close to the tube tip in 100% of controls, but in only 5% of oryzalin-treated tubes. Instead, in 38% of oryzalin tubes, the complex or VN occurred close to the last-formed callose plug; in 40% between or in the middle of plugs; and in 17%, in or near the grain. An aberrant microfilament (MF) cytoskeleton was revealed by expression of a green fluorescent protein-talin fusion protein in living oryzalin-treated tubes. The abnormal MF structures probably resulted from the absence of MTs and impaired - or were a consequence of - VN and GC movement into the tube tip. In oryzalin tubes with several callose plugs, the VN and GC could be in or near the grain, indicating that callose plug synthesis is not dependent on the movement of VN and GC into the tube. VN and GC movement and callose plug formation are apparently independent events, in which the transport of the VN-GC complex must precede callose plug synthesis. Maintenance of the correct developmental program requires an intact MT cytoskeleton, otherwise no fertile pollen tubes are formed.  相似文献   
43.
1. The effects of emergent macrophytes on water turbidity and sediment resuspension in the shallow Kirkkojärvi basin of Lake Hiidenvesi were studied with sediment traps, and concomitant sediment and water samples. The study was conducted during May–August in three different zones of a stand of the emergent Typha angustifolia .
2. Within the stand (5 m from the edge), both the concentration of suspended solids and the rate of sediment resuspension were significantly lower than at the edge and outside the stand (5 m from the edge). The differences between the zones increased towards the end of summer together with the growing stem density. During the study period (82 days), 2210 g dw m−2 of sediment was resuspended in the outer zone. At the edge and in the inner zone, the corresponding numbers were 1414 and 858 g dw m−2, respectively.
3. With the resuspended sediment, 39.4 mg P  m−2 day−1 was brought to the water column outside the stand, 22.4 mg P  m−2 day−1 at the edge and 13.4 mg P  m−2 day−1 within the stand.
4. In early summer, the concentration of suspended solids had a highly significant positive effect on soluble reactive phosphorus (SRP) concentration in the water, whereas in late summer no effect was found. During the study period, phosphorus retention by emergent macrophyte stands corresponded to 3–5% of the present annual external phosphorus loading of the Kirkkojärvi basin.  相似文献   
44.
Abstract Mercaptoethanol (EtSH) was shown to enhance the solubility of the 39.5 kDa outer membrane (OM) protein of elementary bodies of chlamydia trachomatis in detergents. In the presence of mild detergents and EtSH almost selective solubilization of the 39.5 kDa protein and chlamydial LPS was obtained. This solution was further applied to gel filtration in the presence of SDS to purify the 39.5 kDa protein free of LPS.  相似文献   
45.
Immune function was studied in normocalcemic breast cancer patients with bone metastases treated with either dichloromethylene diphosphonate (Cl2MDP) or placebo. The results showed no significant difference between the two patient groups. This suggests that Cl2MDP does not markedly impair the host's defense mechanisms, and in this respect can be safely used in the treatment of patients with resorptive bone disease.  相似文献   
46.
Patterns of genetic diversity and differentiation among five wild and four hatchery populations of Atlantic salmon in the Baltic Sea were assessed based on eight assumedly neutral microsatellite loci and six gene-associated markers, including four expressed sequence tag (EST) linked and two major histocompatibility complex (MHC) linked tandem repeat markers (micro- and mini-satellites). The coalescent simulations based on the method of Beaumont and Nichols (1996, Proc. R. Soc. Lond. Ser. B – Biol. Sci., 263, 1619–1626) indicated that two loci (MHCIIα and Ssa171, with the lowest and highest overall FST estimates, respectively) exhibited significant departures (P<0.05) from the neutral expectations. Another coalescent-based test for selective neutrality (Vitalis et al. 2001, Genetics, 158, 1811–1823) further supported the outlier status of the Ssa171 microsatellite locus but not of the MHCIIα linked minisatellite. In addition, actin related protein linked microsatellite locus was identified with this test as an outlier in six pairwise population comparisons. All genetic diversity estimates revealed more genetic variation in hatchery stocks than in the small wild salmon populations from the Gulf of Finland. However, the wild populations possessed alleles at gene-associated markers (e.g. MHCI and IGF) not found in the hatchery stocks, which together with moderate genetic differentiation and distinctive environmental conditions justifies the special conservation measures for the last remaining native salmon populations in the Gulf of Finland.  相似文献   
47.
Meristem-tip cultures of apple rootstock 'YP' were started at different times of the year over a period of 2 years and the contamination of the cultures was monitored during five subcultures. Bacterial contaminants were isolated to pure cultures, identified by the API test system and appropriate additional tests, and the sensitivity of the most common isolates to different antibiotics was determined. Of the 216 strains isolated from the initiation cultures, 78% were pseudomonads, coryneforms or enterobacteria. Only three bacterial contaminants were found at the multiplication stage. A greater part of the contaminants were likely to originate from the stock plant. Rifampicin (at 50–200 mg 1-1) and cefotaxime (at 250–1500 mg 1-1) were found to be bactericidal against many isolates, but differences between species and strains were found.  相似文献   
48.
1. The existence of phospholipase and lipase activities in the isolated cell envelopes of baker's yeast was demonstrated. 2. The content of phospholipase was found to be markedly higher than that of lipase. 3. After partial enzymic digestion of the isolated cell envelopes, the bulk of the lipolytic activities was recovered in the sedimentable preparations, which consisted of the fragments of the plasma membrane. 4. During repeated washings, the lipase was completely released from the cell envelopes, as were also the bulk of the lipid components and most of the Mg(2+)-dependent adenosine triphosphatase, an enzyme connected with the plasma membrane. The phospholipase was more firmly bound to the preparation but not so firmly as the external saccharase. 5. These results indicate that the lipolytic enzymes found in the cell envelopes are mostly located in the plasma membrane.  相似文献   
49.
The coexistence of competing species relies on niche partitioning. Competitive exclusion is likely inevitable at high niche overlap, but such divide between competitors may be bridged if environmental circumstances displace competitor niches to enhance partitioning. Foraging‐niche dimension can be influenced by environmental characteristics, and if competitors react differently to such conditions, coexistence can be facilitated. We here experimentally approach the partitioning effects of environmental conditions by evaluating the influence of water turbulence on foraging‐niche responses in two competing fish species, Eurasian perch Perca fluviatilis and roach Rutilus rutilus, selecting from planktonic and benthic prey. In the absence of turbulence, both fish species showed high selectivity for benthic chironomid larvae. R. rutilus fed almost exclusively on zoobenthos, whereas P. fluviatilis complemented the benthic diet with zooplankton (mainly copepods). In turbulent water, on the other hand, the foraging‐niche widths of both R. rutilus and P. fluviatilis increased, while their diet overlap simultaneously decreased, caused by 20% of the R. rutilus individuals turning to planktonic (mainly bosminids) prey, and by P. fluviatilis increasing foraging on littoral/benthic food sources. We show that moderate physical disturbance of environments, such as turbulence, can enhance niche partitioning and thereby coexistence of competing foragers. Turbulence affects prey but not fish swimming capacities, with consequences for prey‐specific distributions and encounter rates with fish of different foraging strategies (pause‐travel P. fluviatilis and cruise R. rutilus). Water turbulence and prey community structure should hereby affect competitive interaction strengths among fish species, with consequences for coexistence probability as well as community and system compositions.  相似文献   
50.
The field data from four humic lakes suggested that water colour may have both direct and indirect effects on inter‐ and intra‐specific interactions of perch Perca fluviatilis and roach Rutilus rutilus. The results agree with suggestions that, compared with R. rutilus, P. fluviatilis may be an inferior forager on zooplankton in highly coloured water. As an indirect effect, water colour decreases the coverage of macrophytes and limits suitable littoral habitats, benefiting R. rutilus over P. fluviatilis. Perca fluviatilis benefiting from complex habitats does not have the advantage in macrophyte‐poor highly coloured water.  相似文献   
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