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A new species of Phylloscopus warbler, which we name Phylloscopus calciatilis Limestone Leaf Warbler, is described from central and northern Vietnam and central and northern Laos; it probably also breeds in southernmost China. In morphology, the new species is very similar to Sulphur-breasted Warbler Phylloscopus ricketti , but it is smaller with a proportionately larger bill and rounder wing. Its song and calls are diagnostic. Based on mitochondrial and nuclear DNA, the new species is most closely related to P. ricketti and Yellow-vented Warbler Phylloscopus cantator , and it is inferred to be sister to the latter. The mitochondrial divergences between these three species are at the low end of the variation found in other species of Phylloscopus and Seicercus warblers, but greater than in other taxa generally treated as subspecies. Possible introgressive hybridization between the new species and P. ricketti is discussed, but more data are needed to establish whether it does occur and, if it does, to what extent. The new species appears to have a restricted breeding range in limestone karst environments, where it is locally common and therefore not under any immediate threat. In view of the recognition of the new species, all previous records of P. ricketti sensu lato need to be re-evaluated.  相似文献   
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绞股蓝属的染色体研究   总被引:9,自引:2,他引:9  
报道了葫芦科绞股蓝属(Gynostemma B1.)8种共20个居群的染色体数目,分别为2n=22,33,44,66,88多倍体现象极为普遍。两个亚属;绞股蓝亚属(Subgen.Gynostemma)和喙果藤亚属(Subgen.Triostellum)的染色体基数均为X=11,并结合该属植物形态特征、繁殖方式和地理分布,对普遍出现的多倍体现象进行了讨论。  相似文献   
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目的:探讨全面质量管理模式时老年心血管疾病患者的生活质量的改善情况所起的积极作用,为临床护理提供参考。方法:选择2011年2月至2012年12月在我院心血管内科接受住院治疗的老年患者60例,随机分为常规组和全面管理组。常规组采取基础护理模式,全面管理组在常规护理的基础上对患者进行心理干预、健康教育及饮食管理等。对比两组患者干预前后生活质量改善情况,并对护理服务的满意度进行问卷调查。结果:全面管理组患者的生活质量较干预前明显改善,且患者的心理功能、生活能力及社交功能评分均显著优于常规组,差异具有统计学意义(P〈0.05)。全面管理组患者对心理护理、饮食管理、健康教育及护患沟通的满意度均高于常规护理组,差异具有统计学意义(P〈0.05)。结论:采取全面质量管理的模式对老年心血管疾病患者进行康复指导具有显著的效果,可明显改善患者的生活质量,并且能够提高患者对护理服务的满意度,值得临床推广。  相似文献   
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Delayed gastric emptying symptoms are often reported after chemotherapy. This study aims to characterise the effects of chemotherapy on gastric neuro-muscular function. Patients undergoing elective surgery for oesophago-gastric cancer were recruited. Acetylcholinesterase, nNOS, ghrelin receptor and motilin expressions were studied in gastric sections from patients receiving no chemotherapy (n?=?3) or oesophageal (n?=?2) or gastric (n?=?2) chemotherapy. A scoring system quantified staining intensity (0–3; no staining to strong). Stomach sections were separately suspended in tissue baths for electrical field stimulation (EFS) and exposure to erythromycin or carbachol; three patients had no chemotherapy; four completed cisplatin-based chemotherapy within 6?weeks prior to surgery. AChE expression was markedly decreased after chemotherapy (scores 2.3?±?0.7, 0.5?±?0.2 and 0?±?0 in non-chemotherapy, oesophageal- and gastric-chemotherapy groups (p?<?0.03 each) respectively. Ghrelin receptor and motilin expression tended to increase (ghrelin: 0.7?±?0.4 vs 2.0?±?0.4 and 1.2?±?0.2 respectively; p?=?0.04 and p?=?0.2; motilin: 0.7?±?0.5 vs 2.2?±?0.5 and 2.0?±?0.7; p?=?0.06 and p?=?0.16). Maximal contraction to carbachol was 3.7?±?0.7?g and 1.9?±?0.8?g (longitudinal muscle) and 3.4?±?0.4?g and 1.6?±?0.6 (circular) in non-chemotherapy and chemotherapy tissues respectively (p?<?0.05 each). There were loss of AChE and reduction in contractility to carbachol. The tendency for ghrelin receptors to increase suggests an attempt to upregulate compensating systems. Our study offers a mechanism by which chemotherapy markedly alters neuro-muscular gastric function.  相似文献   
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烟草花叶病毒蚕豆株系基因组全序列分析及结构特征   总被引:4,自引:1,他引:3  
根据已报道的TMV-U1株系核苷酸序列合成引物 ,利用RT-PCR技术获得了覆盖整个烟草花叶病毒蚕豆株系 (TMV-B)基因组的cDNA重组克隆 .结合末端测序技术 ,完成了TMV-B全基因组序列测定 .TMV-B全基因组共有 6 395个核苷酸组成 ,包括 4个开读框 (ORF) ,分别编码 1 2 6ku(含 1 1 1 6个氨基酸 )、1 83ku(含 1 6 1 6个氨基酸 )、30ku(含 2 6 8个氨基酸 )和 1 7.5ku蛋白 (含 1 5 9个氨基酸 ) .TMV-B与TMV-U1相比全基因组同源率达 99.4% ,两病毒基因组 5′ ,3′非编码区和CP基因完全相同 .TMV-B与TMV-U1之间在 1 2 6ku蛋白中有 6个氨基酸差异 ,5 4ku蛋白中有 2个差异 ,30ku蛋白中有 3个差异 .对导致TMV-B侵染蚕豆的可能致病机理进行了分析 .  相似文献   
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随着科学的发展,人造卫星的发射成功,人类开始迈向空间,为揭示太空的真实情况,国内、外学者已进行了大量的探索工作(鲁子贤 1988)。我们利用我国发射的人造卫星进行了搭载试验。本文报道空间环境对微生物生长与遗传性状影响的  相似文献   
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Diabetic foot ulcers are caused by moderate repetitive plantar stresses in the presence of peripheral neuropathy. In severe cases, the development of these foot ulcers can lead to lower extremity amputations. Plantar pressure measurements have been considered a capable predictor of ulceration sites in the past, but some investigations have pointed out inconsistencies when solely relying on this method. The other component of ground reaction forces/stresses, shear, has been understudied due to a lack of adequate equipment. Recent articles reported the potential clinical significance of shear in diabetic ulcer etiology. With the lack of adequate tools, plantar temperature has been used as an alternative method for determining plantar triaxial loading and/or shear. However, this method has not been previously validated. The purpose of this study was to analyze the potential association between exercise-induced plantar temperature increase and plantar stresses. Thirteen healthy individuals walked on a treadmill for 10 minutes at 3.2 km/h. Pre and post-exercise temperature profiles were obtained with a thermal camera. Plantar triaxial stresses were quantified with a custom-built stress plate. A statistically significant correlation was observed between peak shear stress (PSS) and temperature increase (r=0.78), but not between peak resultant stress (PRS) and temperature increase (r=0.46). Plantar temperature increase could predict the location of PSS and PRS in 23% and 39% of the subjects, respectively. Only a moderate linear relationship was established between triaxial plantar stresses and walking-induced temperature increase. Future research will investigate the value of nonlinear models in predicting plantar loading through foot temperature.  相似文献   
10.
Coeliac disease (CD), a T-cell-mediated gluten sensitive enteropathy, affects ∼1% of the UK population and can present with wide ranging clinical features, often being mistaken for Irritable Bowel Syndrome (IBS). Heightened clinical awareness and serological screening identifies those with potential coeliac disease; the diagnosis is confirmed with duodenal biopsies, and symptom improvement with a gluten-free diet. Limitations to diagnosis are false negative serology and reluctance to undergo biopsy. The gut microbiome is altered in several gastrointestinal disorders, causing altered gut fermentation patterns recognisable by volatile organic compounds (VOC) analysis in urine, breath and faeces. We aimed to determine if CD alters the urinary VOC pattern, distinguishing it from IBS. 47 patients were recruited, 27 with established CD, on gluten free diets, and 20 with diarrhoea-predominant IBS (D-IBS). Collected urine was stored frozen in 10 ml aliquots. For assay, the specimens were heated to 40±0.1°C and the headspace analysed by Field Asymmetric Ion Mobility Spectrometry (FAIMS). Machine learning algorithms were used for statistical evaluation. Samples were also analysed using Gas chromatography and mass spectroscopy (GC-MS). Sparse logistic regression showed that FAIMS distinguishes VOCs in CD vs D-IBS with ROC curve AUC of 0.91 (0.83–0.99), sensitivity and specificity of 85% respectively. GCMS showed a unique peak at 4′67 found only in CD, not D-IBS, which correlated with the compound 1,3,5,7 cyclooctatetraene. This study suggests that FAIMS offers a novel, non-invasive approach to identify those with possible CD, and distinguishes from D-IBS. It offers the potential for monitoring compliance with a gluten-free diet at home. The presence of cyclooctatetraene in CD specimens will need further validation.  相似文献   
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