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81.
The chlorinated phenoxyacetic acids 2-methyl-4-chlorophenoxyacetic acid (MCPA), 2,4-dichlorophenoxyacetic acid (2,4-D), 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) and 2,4,5-T butoxyethyl ester and the chlorophenols 2,4-dichlorophenol and 2,4,5-trichlorophenol were tested for genotoxicity in the modified Allium test, which is based on exposure to the test chemicals of growing onions. The mean length of growing roots were measured and chromosome damage was recorded. Of the substances tested, MCPA was the most toxic and the chlorophenoxyacetic acids were more toxic than the chlorophenols. The lower threshold values for growth retardation were below 0.1 ppm for the acids, approx. at 0.1 ppm for the ester and less than 5 ppm for the phenols. Though a monocotyledon, Allium cepa was sensitive enough to respond to even low concentrations of these dicotyledon-selecting pesticides.  相似文献   
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Objective

Patients that initially appear stable on arrival to the hospital often have less intensive monitoring of their vital signs, possibly leading to excess mortality. The aim was to describe risk factors for deterioration in vital signs and the related prognosis among patients with normal vital signs at arrival to a medical emergency department (MED).

Design and setting

Single-centre, retrospective cohort study of all patients admitted to the MED from September 2010-August 2011.

Subjects

Patients were included when their vital signs (systolic blood pressure, pulse rate, respiratory rate, Glasgow Coma Scale, oxygen saturation and temperature) were within the normal range at arrival. Deterioration was defined as a deviation from the defined normal range 2–24 hours after arrival.

Results

4292 of the 6257 (68.6%) admitted to the MED had a full set of vital signs at first presentation, 1440/4292 (33.6%) had all normal vital signs and were included in study, 44.0% were male, median age 64 years (5th/95th percentile: 21–90 years) and 446/1440 (31.0%) deteriorated within 24 hours. Independent risk factors for deterioration included age 65–84 years odds ratio (OR): 1.79 (95% confidence interval [CI]: 1.27–2.52), 85+ years OR 1.67 (95% CI: 1.10–2.55), Do-not-attempt-to-resuscitate order OR 3.76 (95% CI: 1.37–10.31) and admission from the open general ED OR 1.35 (95% CI: 1.07–1.71). Thirty-day mortality was 7.9% (95% CI: 5.5–10.7%) among deteriorating patients and 1.9% (95% CI: 1.2–3.0%) among the non-deteriorating, hazard ratio 4.11 (95% CI: 2.38–7.10).

Conclusions

Among acutely admitted medical patients who arrive with normal vital signs, 31.0% showed signs of deterioration within 24 hours. Risk factors included old age, Do-not-attempt-to-resuscitate order, admission from the open general ED. Thirty-day mortality among patients with deterioration was four times higher than among non-deteriorating patients. Further research is needed to determine whether intensified monitoring of vital signs can help to prevent deterioration or mortality among medical emergency patients.  相似文献   
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IntroductionIt has previously been shown that an increased number of antibodies against citrullinated peptides/proteins (ACPA) predate the onset of rheumatoid arthritis (RA). Over time antibody positivity expands, involving more specific responses when approaching the onset of symptoms. We investigated the impact of human leukocyte antigen-shared epitope (HLA-SE) alleles and smoking on the development of ACPA, as well as in combination with ACPA during the state of quiescent autoimmunity (before the onset of symptoms), on the development of RA.MethodsBlood samples donated to the Medical Biobank of Northern Sweden from individuals prior to the onset of symptoms of RA (n = 370) and after onset (n = 203) and from population-based controls (n = 585) were used. Antibodies against 10 citrullinated peptides, fibrinogen (Fibα561-583, α580-600, ß62-81a, ß62-81b, ß36-52), vimentin (Vim2-17, 60-75), filaggrin (CCP-1/Fil307-324), α-enolase (CEP-1/Eno5-21), collagen type II (citC1359-369), and anti-cyclic citrullinated peptide (CCP)2 antibodies were analysed.ResultsHLA-SE-positive individuals were more frequently positive for ACPA compared with HLA-SE-negative individuals prior to the onset of symptoms of RA, particularly for antibodies against CEP-1 and Fibß62-81a (72). Smoking was associated with antibodies against Vim2-17 and citC1359-369. HLA-SE and smoking showed increasing association to the presence of the antibodies closer to disease onset. The highest odds ratio (OR) for development of RA was for the combination of HLA-SE alleles and ACPA positivity, especially for antibodies against Fibß62-81b, CCP-1/Fil307-324, and Fibβ36-52. A gene-environment additive interaction between smoking and HLA-SE alleles for the risk of disease development was found, with the highest OR for individuals positive for antibodies against Fibβ36-52, CEP-1, and Fibα580-600.ConclusionsThe relationships between antibodies against the different ACPA specificities, HLA-SE, and smoking showed a variable pattern in individuals prior to the onset of RA. The combination of smoking and HLA-SE alleles was significantly associated with the development of some of the antibody specificities closer to onset of symptoms, and these associations remained significant at diagnosis. An additive gene-environment interaction was found for several of the antibodies for the development of RA.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-015-0638-x) contains supplementary material, which is available to authorized users.  相似文献   
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Background

The aim of the study was to estimate risk factors for hospitalization due to sepsis and to determine whether these risk factors vary by age and gender.

Methods

We performed a population-based case-control study of all adult patients admitted to a medical ED from September 2010 to August 2011. Controls were sampled within the hospital catchment-area. All potential cases were manually validated using a structured protocol. Vital signs and laboratory values measured at arrival were registered to define systemic inflammatory response syndrome and organ dysfunction. Multivariable logistic regression was used to elucidate which predefined risk factors were associated with an increased or decreased risk hospitalization due to sepsis.

Results

A total of 1713 patients were admitted with sepsis of any severity. The median age was 72 years (interquartile range: 57–81 years) and 793 (46.3%) were male. 621 (36.3%) patients were admitted with sepsis, 1071 (62.5%) with severe sepsis and 21 (1.2%) with septic shock. Episodes with sepsis of any severity were associated with older age (85+ years adjusted OR 6.02 [95%CI: 5.09–7.12]), immunosuppression (4.41 [3.83–5.09]), alcoholism-related conditions (2.90 [2.41–3.50]), and certain comorbidities: psychotic disorder (1.90 [1.58–2.27]), neurological (1.98 [1.73–2.26]), respiratory (3.58 [3.16–4.06]), cardiovascular (1.62 [1.41–1.85]), diabetes (1.82 [1.57–2.12]), cancer (1.44 [1.22–1.68]), gastrointestinal (1.71 [1.44–2.05]) and renal (1.46 [1.13–1.89]). The strength of the observed associations for comorbid factors was strongest among younger individuals.

Conclusions

Hospitalization due to sepsis of any severity was associated with several independent risk factors, including age and comorbid factors.  相似文献   
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High-throughput DNA sequencing technologies are increasingly becoming powerful systems for the comprehensive analysis of variations in whole genomes or various DNA libraries. As they are capable of producing massive collections of short sequences with varying lengths, a major challenge is how to turn these reads into biologically meaningful information. The first stage is to assemble the short reads into longer sequences through an in silico process. However, currently available software/programs allow only the assembly of abundant sequences, which apparently results in the loss of highly variable (or rare) sequences or creates artefact assemblies. In this paper, we describe a novel program (DNAseq) that is capable of assembling highly variable sequences and displaying them directly for phylogenetic analysis. In addition, this program is Microsoft Windows-based and runs by a normal PC with 700MB RAM for a general use. We have applied it to analyse a human naive single-chain antibody (scFv) library, comprehensively revealing the diversity of antibody variable complementarity-determining regions (CDRs) and their families. Although only a scFv library was exemplified here, we envisage that this program could be applicable to other genome libraries.  相似文献   
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