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981.
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The severity and/or progression of osteonecrosis of the femoral head (ONFH) are commonly assessed by radiography, nuclear magnetic resonance image which aren’t invariably correlated to severity of disease and may be disturbed by other factors. Consequently, exploring the novel biochemical signatures of ONFH may be beneficial for diagnosing and understanding this disease. In this work, a bone trabecula metabolomics was undertaken to determine the expression pattern of low molecular mass metabolites in patients of femoral head necrosis based on the ultra-performance liquid chromatography/time-of-flight tandem mass spectrometry (UPLC/TOF MS/MS). Histological study showed that necrotic bone was characterized by necrosis, fibrosis and lacuna, but adjacent “normal” bone was pathologically normal. Principal component analysis in combination with orthogonal partial least-squares discrimination analysis was used to find out changed metabolites. MS/MS was used to speculate the corresponding molecule. Both osteonecrotic bone trabecula (ONBT) and adjacent “normal” bone trabecula (ANBT) showed higher levels of amino acids, such as proline, arginine, glutamine, dipeptides and lower levels of antioxidants. Most disrupted lipids, such as fatty acid esters, glycerophospholipids, sphingolipids, were found in osteonecrotic zone. The area under the receiver operating characteristic curve of combinational biomarkers (d-arginine, l-proline, l-carnitine, inosine) in ONBT and ANBT was 0.996 and 0.950, respectively. Our findings might provide a significant insight to understand the metabolic mechanism and diagnosis biomarkers of ONFH in the future.  相似文献   
984.
The aim of the experiment on 180 weaned piglets (8.9 kg body weight) was to investigate the influence of high fibre diets formulated with different fibrous ingredients on performance, nutrient digestibility, diarrhoea incidence and numbers of faecal microbiota. The dietary treatments included a Control diet and five high fibre diets formulated with different fibre sources including wheat bran, soybean hulls, naked oat hulls, palm kernel expeller and bamboo fibre. The high fibre diets averaged 14.6% neutral detergent fibre with different non-starch polysaccharides (NSP) components and were fed ad libitum for 28 d. Faecal samples were collected during the last 3 d of the experiment and the apparent total tract digestibility of nutrients and fibre components were determined. Pigs fed the Control and wheat bran diets had a higher (≤ 0.05) average daily gain (ADG) than pigs fed the palm kernel expeller and bamboo meal diets. The reduced ADG for pigs appeared to be related to reductions in the digestibility of gross energy and dry matter, respectively. The feed-to-gain ratio was significantly higher (≤ 0.05) for pigs fed the fibre diets. The digestibility of NSP components was different among the treatments. The diarrhoea incidence was not affected by treatments. The abundance of faecal bifidobacteria was significantly higher (≤ 0.05) for pigs fed the wheat bran diet than for pigs fed the bamboo meal diet. It was concluded that the diets formulated with different fibre sources when fed to weaned piglets have different effects on pig performance, nutrient digestibility and numbers of faecal microbiota. The wheat bran diet rich in arabinoxylans enabled a better performance than the other tested diets with fibre addition.  相似文献   
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986.
Impatiens L. is one of the largest angiosperm genera, containing over 1000 species, and is notorious for its taxonomic difficulty. Here, we present, to our knowledge, the most comprehensive phylogenetic analysis of the genus to date based on a total evidence approach. Forty‐six morphological characters, mainly obtained from our own investigations, are combined with sequence data from three genetic regions, including nuclear ribosomal ITS and plastid atpB‐rbcL and trnL‐F. We include 150 Impatiens species representing all clades recovered by previous phylogenetic analyses as well as three outgroups. Maximum‐parsimony and Bayesian inference methods were used to infer phylogenetic relationships. Our analyses concur with previous studies, but in most cases provide stronger support. Impatiens splits into two major clades. For the first time, we report that species with three‐colpate pollen and four carpels form a monophyletic group (clade I). Within clade II, seven well‐supported subclades are recognized. Within this phylogenetic framework, character evolution is reconstructed, and diagnostic morphological characters for different clades and subclades are identified and discussed. Based on both morphological and molecular evidence, a new classification outline is presented, in which Impatiens is divided into two subgenera, subgen. Clavicarpa and subgen. Impatiens; the latter is further subdivided into seven sections.  相似文献   
987.
Background:Systematic reviews support nasal saline irrigation for chronic or recurrent sinus symptoms, but trials have been small and few in primary care settings. Steam inhalation has also been proposed, but supporting evidence is lacking. We investigated whether brief pragmatic interventions to encourage use of nasal irrigation or steam inhalation would be effective in relieving sinus symptoms.Methods:We conducted a pragmatic randomized controlled trial involving adults (age 18–65 yr) from 72 primary care practices in the United Kingdom who had a history of chronic or recurrent sinusitis and reported a “moderate to severe” impact of sinus symptoms on their quality of life. Participants were recruited between Feb. 11, 2009, and June 30, 2014, and randomly assigned to 1 of 4 advice strategies: usual care, daily nasal saline irrigation supported by a demonstration video, daily steam inhalation, or combined treatment with both interventions. The primary outcome measure was the Rhinosinusitis Disability Index (RSDI). Patients were followed up at 3 and 6 months. We imputed missing data using multiple imputation methods.Results:Of the 961 patients who consented, 871 returned baseline questionnaires (210 usual care, 219 nasal irrigation, 232 steam inhalation and 210 combined treatment). A total of 671 (77.0%) of the 871 participants reported RSDI scores at 3 months. Patients’ RSDI scores improved more with nasal irrigation than without nasal irrigation by 3 months (crude change −7.42 v. −5.23; estimated adjusted mean difference between groups −2.51, 95% confidence interval −4.65 to −0.37). By 6 months, significantly more patients maintained a 10-point clinically important improvement in the RSDI score with nasal irrigation (44.1% v. 36.6%); fewer used over-the-counter medications (59.4% v. 68.0%) or intended to consult a doctor in future episodes. Steam inhalation reduced headache but had no significant effect on other outcomes. The proportion of participants who had adverse effects was the same in both intervention groups.Interpretation:Advice to use steam inhalation for chronic or recurrent sinus symptoms in primary care was not effective. A similar strategy to use nasal irrigation was less effective than prior evidence suggested, but it provided some symptomatic benefit. Trial registration: ISRCTN, no. 88204146.Rhinosinusitis probably affects more than 25 million Americans and 2.5 million Canadians.1 Quality of life of patients with chronic or recurrent sinusitis has been reported to be similar to congestive heart disease and chronic pulmonary disease.2 Antibiotics are prescribed for nearly all patients with sinusitis,3 but the evidence is modest4 and an international priority is to contain antibiotic resistance.5 Steam inhalation is widely advocated in rhinosinusitis, but a Cochrane review of steam for the “common cold” found equivocal evidence,6 and a recent primary care trial found no benefit and some harm (mild thermal injury) for pragmatic advice to inhale steam twice daily for a range of respiratory tract infections.7 The Cochrane review of nasal saline irrigation reported benefit.8 However, most of the trials were small, mainly from secondary care settings, and the review documented symptom data from only 129 participants, with high heterogeneity. Two small randomized controlled trials included some participants from primary care settings.9,10 One of the studies compared a gravity-based nasal irrigation device with routine care among 76 participants mainly from primary care settings; it found that symptoms improved very little in the control group (by 1 point on the Rhinosinusitis Disability Index [RSDI] converted to a 100-point scale), as compared with a 14-point improvement in the irrigation group.9 The other (published since the Cochrane review) compared a positive-pressure squeeze bottle with saline nasal spray among 121 volunteers from various sources and found an 8.5-point improvement in the control group, as compared with a 15-point improvement in the irrigation group.10We conducted a large pragmatic randomized controlled trial of the effectiveness of brief advice to use nasal irrigation or steam inhalation in routine primary care for chronic or recurrent sinus symptoms.  相似文献   
988.
Most flower-visiting insects employ highly-evolved organs to feed themselves rapidly and efficiently on the floral nectar. A honey bee drives its segmented tongue (glossa) covered by dense hairs reciprocatingly to load nectar. A high-speed camera system ameliorated by a microscope revealed morphological changes in glossal surfaces during live honey bees’ nectar dipping and surface configurations through the stretching of postmortem honey bees’ glossae. Both the in vivo and postmortem observations reveal that shortening and lengthening of the glossal segments perform high concordance with the erection of glossal hairs, which aids in developing deformable gaps between rows of glossal hairs during nectar trapping. A model was proposed to evaluate the nectar-intake volume considering the experimentally-measured average erection angle and tongue elongation length during nectar feeding. The theoretical results fit the experimental data well and disclose that these two factors contribute to an augmentation of nectar-intake observably. We also theoretically present that the extendible and deformable glossae have advantages for the polylectic feeding behavior.  相似文献   
989.
990.
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