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101.
P. Vajkoczy R. Goldbrunner M. Farhadi G. Vince L. Schilling J. C. Tonn P. Schmiedek M. D. Menger 《International journal of developmental neuroscience》1999,17(5-6):557-563
To simultaneously assess glioma cell invasion and glioma angiogenesis in vivo by non-invasive and quantitative means, DiI-labeled C6 glioma spheroids were implanted into the dorsal skinfold chamber preparation of nude mice (n = 6). Heat-inactivated spheroids served as controls to distinguish between active and passive cell spread. Using multi-fluorescent intravital videomicroscopy, glioma cell migration was analyzed on days 1-4, 6, and 10 and spheroid vascularization was analyzed on days 3, 6, and 10 after implantation. Additionally, C6 glioma spheroids were implanted into the chronic cranial window of nude mice as an orthotopic implantation site (n = 4). In the dorsal skinfold chamber, spheroids were vascularized within 10 days and revealed a tumor-specific microvasculature. In parallel, individual glioma cells detached from the spheroid edge and migrated centrifugally demonstrating an affinity to tumor and host vessels. Glioma cells demonstrated a heterogeneous pattern of their regional migratory activity (0.2-9.6 microm/h) which correlated well with regional glioma angiogenesis (r = 0.733). Using the cranial window, glioma cells spread similarly demonstrating an affinity to the perivascular space of pial/subpial vessels with preference to the arteriolar segments. Intravital fluorescence microscopy represents a versatile technique to assess the complex relationship between glioma-driven angiogenesis and glioma cell invasion. 相似文献
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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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106.
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107.
Role of cytomegalovirus in sensorineural hearing loss of children: a case-control study Tehran, Iran 总被引:1,自引:0,他引:1
Samileh N Ahmad S Mohammad F Framarz M Azardokht T Jomeht E 《International journal of pediatric otorhinolaryngology》2008,72(2):203-208
BACKGROUND: Congenital CMV is the most common cause of nonhereditary sensorineural hearing loss in children. More than 40% of deafness cases with an unknown cause are due to congenital CMV. When CMV infection is diagnosed in the first year of life, treatment with gancyclovir is recommended and is associated with diminished occurrence of SNHL. Previous studies in Tehran showed congenital CMV infection developed in 2.6% of neonates. OBJECTIVE: To determine the role of cytomegalovirus in sensorineural hearing loss in children by comparing the CMV antibodies quantitatively between SNHL and controls. METHODS AND MATERIALS: This case-control study was done in the ENT Department of Hazrat Rasoul Akram Hospital in Tehran (2002-2003). This study was carried out based on diagnostic parameters (AAO criteria) for SNHL and a healthy control. We compared the specific cytomegalovirus antibodies (IgM and IgG measured by ELISA method) in 95 blood samples of infants with SNHL (mean age=35+/-30 months) and 63 healthy matched infants (mean age=38.7+/-27.3 months) as controls. 59.6% of cases were male; 40.4% were female. Acute and previous immunity to cytomegalovirus (IgM and IgG) was found in 34.7% and 72.6% of SNHL children, acute infection detected in 3.5% of controls, previous immunity (IgG) detected in 94.7% of them. Acute CMV infection was higher in the cases (P-value=0.000) but previous immunity (CMV-IgG) was higher in the controls (P-value=0.001). Mean age of cases with acute infection (CMV-IgM) was 40 months and for previous immunity (CMV-IgG) was 35 months in SNHL cases and 40 months in controls, respectively. CONCLUSION: Cytomegalovirus is one of the most common infectious agents in SNHL children compared to the healthy children. Probably both congenital and acquired CMV can induce progressive hearing loss in our cases. We prefer at least in our country to consider seropositive (CMV-IgM) SNHL children (less than 1 year old) as congenital form. But we are not able to differentiate the congenital from the acquired infection in seropositive (CMV-IgM) SNHL children after first year of life. It should be subjected to randomized controlled trial for treatment of acquired type of CMV infection in SNHL children with ganciclovir. 相似文献
108.
109.
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
110.
Hajar Adib Rad Zahra Basirat Fatemeh Bakouei Ali Akbar Moghadamnia Soraya Khafri Zeynab Farhadi Kotenaei Maryam Nikpour Somayeh Kazemi 《Taiwanese journal of obstetrics & gynecology》2018,57(6):806-809