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1.
We investigated muscle strength, aerobic power, and occupational and leisure-time physical loading as predictors of back pain in a 5-year follow-up study. A cohort of 456 adults aged 25, 35, 45 and 55 years, free of back pain, participated in measurements of anthropometric characteristics, aerobic power and muscle strength characteristics at baseline. The subjects' levels and types of physical activity and occupational physical loading were also determined. At 5 years after the baseline examinations 356 of these subjects (78.1 %) were reached by mail, and 262 of them (73.6%) properly completed and returned a questionnaire including a detailed back pain history for the 5 years following the baseline measurements. Of this number 56 subjects (21 %) who reported back pain ( > 30 on a scale from 0 to 100) and functional impairment during the 5-year follow-up composed the marked back pain group. Other subjects (n = 71, 27%) noting lesser symptoms were included in the mild back pain group; 135 subjects (52%) reported having had no back pain. The subjects with marked back pain were on average taller than the subjects without back pain, while no such difference was found in body mass. Heavy occupational musculoskeletal loading (P = 0.005) and high general occupational physical demands (P = 0.036) predicted future back pain. Leisuretime physical activity, aerobic power or muscle strength characteristics were not predictive of future back pain.  相似文献   
2.
Despite modern stent technology and effective antiplatelet therapy, metallic stents carry the risk of (sub)acute thrombosis. Our aim was to examine short-term differences in platelet deposition and coagulation activation between biodegradable polylactide (PLA), heparin-polycaprolactone-L-lactide-coated polylactide (hepa-P(CL95/L-LA5)-PLA), and stainless steel (SS) stent struts. Gel-filtered platelets (GFP) and platelet-rich plasma (PRP) were labeled with 10 nM (3)H-serotonin. Platelet deposition was measured after incubation of the stent struts in human serum albumin-coated wells at 37 degrees C in either GFP or PRP. Platelet morphology was studied by scanning electron microscopy (SEM). For coagulation activation, the stent struts were incubated in either PRP or platelet-poor plasma (PPP), anticoagulated with D-phenylalanyl-L-prolyl-L-arginine chloromethyl ketone (PPACK), followed by measurement of fibrinogen, thrombin time (TT), prothrombin fragment 1+2 (F1+2), and thrombin-antithrombin complex (TAT). SS showed adherence of larger amounts of GFPs than did PLA at a platelet density of 300 x 10(6)/mL (p < 0.05). Furthermore, representative SEM studies showed more platelet spreading on SS than on PLA stent struts. Between PLA and SS, coagulation activity did not differ at any assessment. Based on prolonged TT values in plasma, the heparin coating strongly inhibited coagulation (p < 0.05). The values of soluble TAT and F1+2 for PLA were similar to those of controls, i.e., to incubated suspensions without a stent strut. In conclusion, when compared with stainless steel, both PLA and hepa-P(CL95/L-LA5)-PLA appear hemocompatible as intravascular stent materials.  相似文献   
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Five enclosed double-stranded RNA (dsRNA) bands in electrophoresis, probably of viral origin, were found from a single isolate (SurS4) of Gremmeniella abietina var. abietina type A. Analysis of the dsRNAs revealed that they represented three different viruses, named as Gremmeniella abietina mitochondrial RNA virus S2 (GaMRV-S2), Gremmeniella abietina RNA virus MS2 (GaRV-MS2) and Gremmeniella abietina RNA virus L2 (GaRV-L2). The genome of GaMRV-S2 was 2587 base pairs (bp) long and had a very low GC content (31%). Sequence variations occurred at both ends. The genome coded for a putative RNA-dependent RNA polymerase (RdRp) under a mitochondrial translation code. The GaRV-MS2 genome was composed of three dsRNA molecules (1781 bp, 1586 bp and 1186 bp). They coded for a putative RdRp, a coat protein (CP) and a protein with an unknown function, respectively. The GaRV-L2 genome was 5129 bp long and contained two ORFs. The 5′-proximal ORF coded for a putative CP, whereas the 3′-proximal ORF encoded for a putative RdRp. The buoyant density of GaRV-MS2 and GaRV-L2 were 1.37 and 1.42 g/ml, respectively. GaMRV-S2, GaRV-MS2 and GaRV-L2 were closely related to the previously described viruses GaMRV-S1, GaRV-MS1 and GaRV-L1, respectively, and are putative members of the genera Mitovirus, Partitivirus and Totivirus, respectively. This is the first report on the occurrence of viruses of all these different genera in a single fungal isolate.  相似文献   
7.

Introduction

Indications for renal replacement therapy (RRT) have not been generally standardized and vary among intensive care units (ICUs). We aimed to assess the proportion, indications, and modality of RRT, as well as the association between the proportion of RRT use and 90-day mortality in patients with septic shock in Finnish adult ICUs.

Methods

We identified patients with septic shock from the prospective observational multicenter FINNAKI study conducted between 1 September 2011 and 1 February 2012. We divided the ICUs into high-RRT and low-RRT ICUs according to the median of the proportion of RRT-treated patients with septic shock. Differences in indications, and modality of RRT between ICU groups were assessed. Finally, we performed an adjusted logistic regression analysis to evaluate the possible association of the ICU group (high vs. low-RRT) with 90-day mortality.

Results

Of the 726 patients with septic shock, 131 (18.0%, 95% CI 15.2 to 20.9%) were treated with RRT. The proportion of RRT-treated patients varied from 3% up to 36% (median 19%) among ICUs. High-RRT ICUs included nine ICUs (354 patients) and low-RRT ICUs eight ICUs (372 patients). In the high-RRT ICUs patients with septic shock were older (P = 0.04), had more cardiovascular (P <0.001) and renal failures (P = 0.003) on the first day in the ICU, were more often mechanically ventilated, and received higher maximum doses of norepinephrine (0.25 μg/kg/min vs. 0.18 μg/kg/min, P <0.001) than in the low-RRT ICUs. No significant differences in indications for or modality of RRT existed between the ICU groups. The crude 90-day mortality rate for patients with septic shock was 36.2% (95% CI 31.1 to 41.3%) in the high-RRT ICUs compared to 33.9% (95% CI 29.0 to 38.8%) in the low-RRT ICUs, P = 0.5. In an adjusted logistic regression analysis the ICU group (high-RRT or low-RRT ICUs) was not associated with 90-day mortality.

Conclusions

Patients with septic shock in ICUs with a high proportion of RRT had more severe organ dysfunctions and received more organ-supportive treatments. Importantly, the ICU group (high-RRT or low-RRT group) was not associated with 90-day mortality.  相似文献   
8.
OBJECTIVES: To evaluate the effects of a multifactorial fall prevention program on falls and to identify the subgroups that benefit the most.
DESIGN: Randomized controlled trial.
SETTING: Community-dwelling subjects who had fallen at least once during the previous 12 months.
PARTICIPANTS: Five hundred ninety-one subjects randomized into intervention (IG) (n=293) and control (CG) (n=298) groups.
INTERVENTION: A multifactorial 12-month fall prevention program.
MEASUREMENTS: Incidence of falls.
RESULTS: The intervention did not reduce the incidence of falls overall (incidence rate ratio (IRR) for IG vs CG=0.92, 95% confidence interval (CI)=0.72–1.19). In subgroup analyses, significant interactions between subgroups and groups (IG and CG) were found for depressive symptoms ( P =.006), number of falls during the previous 12 months ( P =.003), and self-perceived risk of falling ( P =.045). The incidence of falls decreased in subjects with a higher number of depressive symptoms (IRR=0.50, 95% CI=0.28–0.88), whereas it increased in those with a lower number of depressive symptoms (IRR=1.20, 95% CI=0.92–1.57). The incidence of falls decreased also in those with at least three previous falls (IRR=0.59, 95% CI=0.38–0.91) compared to those with one or two previous falls (IRR=1.28, 95% CI=0.95–1.72). The intervention was also more effective in subjects with high self-perceived risk of falling (IRR=0.77, 95% CI=0.55–1.06) than in those with low self-perceived risk (IRR=1.28, 95% CI=0.88–1.86).
CONCLUSION: The program was not effective in reducing falls in the total sample of community-dwelling subjects with a history of falling, but the incidence of falls decreased in participants with a higher number of depressive symptoms and in those with at least three falls.  相似文献   
9.
Engineering anthracycline biosynthesis toward angucyclines   总被引:2,自引:0,他引:2       下载免费PDF全文
The biosynthesis pathways of two anthracyclines, nogalamycin and aclacinomycin, were directed toward angucyclines by using an angucycline-specific cyclase, pgaF, isolated from a silent antibiotic biosynthesis gene cluster. Addition of pgaF to a gene cassette that harbored the early biosynthesis genes of nogalamycin resulted in the production of two known angucyclinone metabolites, rabelomycin and its precursor, UWM6. Substrate flexibility of pgaF was demonstrated by replacement of the nogalamycin minimal polyketide synthase genes in the gene cassette with the equivalent aclacinomycin genes together with aknE2 and aknF, which specify the unusual propionate starter unit in aclacinomycin biosynthesis. This modification led to the production of a novel angucyclinone, MM2002, in which the expected ethyl side chain was incorporated into the fourth ring.  相似文献   
10.
Increased levels of nitric oxide (NO) and prostaglandins (PG) are present in the synovial fluid from patients with rheumatoid arthritis and osteoarthritis. Interleukin-1 (IL-1) has been shown to induce the synthesis of both of these mediators. The present work was designed to study the interactions of NO and PGE2 synthesis induced by IL-1 in rat articular cartilage. Incubation of intact cartilage with IL-1 resulted in different dose response curves for NO and PGE2 synthesis. Two inhibitors of nitric oxide synthase N-monomethyl-L-arginine (L-NMMA) and L-N-iminoethyl-ornithine, (L-NIO), abolished the IL-1-induced nitrite production but failed to have any influence on the PGE2 synthesis. Exogenous NO, produced by two chemically different NO-releasing compounds (SIN-1 and GEA 3175) had no effect on PGE2 synthesis in articular cartilage. Dexamethasone and ketoprofen inhibited IL-1 induced PGE2 production, while nitrite synthesis remained unaltered. Acetylsalisylic acid (ASA) reduced PGE2 synthesis and had a slight inhibitory action also on NO production. In conclusion, our results show, that IL-1 induces the synthesis of both PGE2 and NO in articular cartilage but these two inflammatory mediators are not mediating the synthesis of one another.  相似文献   
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