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排序方式: 共有574条查询结果,搜索用时 14 毫秒
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Marchenko V Yu Alekseev A Yu Tserennorov D Yurlov AK Susloparov IM Sharshov KA Ilyinykh FA Zolotykh SI Abmed D Otgonbaatar D Shestopalov AM 《Asian Pacific journal of tropical medicine》2010,3(2):90-93
ObjectiveTo present results of virological study of wild birds inhabiting Western Mongolia.MethodsOver a period of 2003–2008, we isolated 13 influenza A viruses: H1N1, H3N6, H13N8 and H4N6 subtypes. We did not isolate any H5N1 subtype, that still cause epizooty in wild birds and poultry.ResultsWe revealed taxonomic and ecological heterogeneity of the birds involved in maintenance of circulation of influenza viruses in the given territory. Influenza viruses were isolated from birds of 6 orders; among them there are species preferring water and semi-aquatic biotopes, one species preferring dry plain region, and also one species which can inhabit both dry and water biotopes.ConclusionsRepresentatives of all main orders of Western Mongolia avifauna are involved in support of influenza A virus circulation, highly pathogenic H5N1 influenza viruses were registered in Mongolia thus it's necessary to continue permanent influenza virus surveillance in wild birds' populations. 相似文献
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Jane Sj?gren Joey FA Ubachs Henrik Engblom Marcus Carlsson H?kan Arheden Einar Heiberg 《Journal of cardiovascular magnetic resonance》2012,14(1):10
Background
T2-weighted cardiovascular magnetic resonance (CMR) has been shown to be a promising technique for determination of ischemic myocardium, referred to as myocardium at risk (MaR), after an acute coronary event. Quantification of MaR in T2-weighted CMR has been proposed to be performed by manual delineation or the threshold methods of two standard deviations from remote (2SD), full width half maximum intensity (FWHM) or Otsu. However, manual delineation is subjective and threshold methods have inherent limitations related to threshold definition and lack of a priori information about cardiac anatomy and physiology. Therefore, the aim of this study was to develop an automatic segmentation algorithm for quantification of MaR using anatomical a priori information.Methods
Forty-seven patients with first-time acute ST-elevation myocardial infarction underwent T2-weighted CMR within 1 week after admission. Endocardial and epicardial borders of the left ventricle, as well as the hyper enhanced MaR regions were manually delineated by experienced observers and used as reference method. A new automatic segmentation algorithm, called Segment MaR, defines the MaR region as the continuous region most probable of being MaR, by estimating the intensities of normal myocardium and MaR with an expectation maximization algorithm and restricting the MaR region by an a priori model of the maximal extent for the user defined culprit artery. The segmentation by Segment MaR was compared against inter observer variability of manual delineation and the threshold methods of 2SD, FWHM and Otsu.Results
MaR was 32.9 ± 10.9% of left ventricular mass (LVM) when assessed by the reference observer and 31.0 ± 8.8% of LVM assessed by Segment MaR. The bias and correlation was, -1.9 ± 6.4% of LVM, R = 0.81 (p < 0.001) for Segment MaR, -2.3 ± 4.9%, R = 0.91 (p < 0.001) for inter observer variability of manual delineation, -7.7 ± 11.4%, R = 0.38 (p = 0.008) for 2SD, -21.0 ± 9.9%, R = 0.41 (p = 0.004) for FWHM, and 5.3 ± 9.6%, R = 0.47 (p < 0.001) for Otsu.Conclusions
There is a good agreement between automatic Segment MaR and manually assessed MaR in T2-weighted CMR. Thus, the proposed algorithm seems to be a promising, objective method for standardized MaR quantification in T2-weighted CMR. 相似文献86.
目的探讨肠缺血再灌流损伤时肠内营养与肠粘膜血流改变的关系.方法SD大鼠分为三组,先制作空肠袋,然后将激光多谱勒探头和肠粘膜张力计放置在空肠袋两端,分别向袋内注射丙氨酸、葡萄糖及甘露醇.用动脉夹阻断肠系膜上动脉血流60分后,再恢复灌流60分.分别测定肠粘膜血流量和局部PCO2张力(PrCO2).结果缺血再灌流过程中,与甘露醇组比较,葡萄糖组粘膜血流量显著增加,PrCO2降低.结论缺血再灌流过程中,肠内给予葡萄糖能增加肠粘膜血流量,对缺血再灌流损伤的肠道提供保护作用. 相似文献
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Ghazzawi IM; Sarraf MG; Taher MR; Khalifa FA 《Human reproduction (Oxford, England)》1998,13(2):348-352
A prospective study was carried out to compare the fertilizing capability
and pregnancy outcome following intracytoplasmic sperm injection (ICSI)
using spermatozoa obtained from ejaculates, or surgically from epididymis
or seminiferous tubules. A total of 77 ICSI cycles (one per patient) was
included. In all, 28 patients had severe oligoasthenoteratozoospermia, 19
patients had obstructive azoospermia and 30 patients had non-obstructive
azoospermia. The main outcome measures were fertilization rate per injected
metaphase II oocyte and the clinical pregnancy rate per embryo transferred
back to the female recipients. In patients with severe
oligoasthenoteratozoospermia, the fertilization and pregnancy rates were 79
and 25 %. In patients with obstructive azoospermia, for whom epididymal
spermatozoa were used, these were 75 and 28%, and in the non-obstructive
group for which testicular spermatozoa were used for injection, they were
69 and 21% respectively. These rates were not significantly different in
the three groups (P = 0.85 and P = 0.14 respectively), suggesting that
spermatozoa from the ejaculates and epididymal or testicular biopsies are
able to fertilize equally by using ICSI. Live birth per embryo transfer was
significantly reduced in patients with non-obstructive azoospermia compared
to the other two groups. The high abortion rate (50%) in the group in which
testicular spermatozoa were used raises doubts about the developmental
competence of such embryos.
相似文献
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目的研究安氏Ⅰ类错患者中,采用微型种植体作支抗,压低下颌磨牙的临床效果及其作用特点。方法选择12例成人患者,将24枚微型种植体植于下颌第一磨牙近、远中的颊侧牙槽骨内,Ni-Ti螺旋弹簧拉长后分别连接于下颌第一磨牙带环颊侧,来压低下颌第一磨牙。测量磨牙的压低量、颊舌向的位置变化、近远中倾斜度以及磨牙移动的速度,并通过治疗前后的X线片对比以观察磨牙牙根有无吸收,牙周膜腔的变化情况。通过测量下颌第二磨牙与下颌中切牙的位置变化来衡量支抗强弱。结果下颌第一磨牙平均压低3.5mm,疗程5.2个月,平均移动速度0.67mm/月;磨牙牙冠近颊尖、远颊尖分别颊向移动1.2mm、1.3mm。磨牙牙根没有吸收,牙周膜腔宽度没有改变。下颌第二磨牙与下颌中切牙的位置没有改变。结论所有下颌磨牙均被压低到了恰当的位置,为对颌牙的修复治疗提供了足够的间隙。同时该方法临床操作简单易行,适于推广。 相似文献