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101.
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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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.

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.
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   
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109.
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.

Objective

Menstrual pain is a periodic pain which happens during the days of menses. The menstrual disturbances as a health problem among young girls affect not only reproductive, but also psychical health and quality of life. This study was done with the goal of comparing the effect of Ginger and Novafen on the menstrual pain.

Materials and methods

This crossover clinical trial study was done in Iran on 168 single girl students 18–26 years old in Babol University of Medical Sciences with primary menstrual pain. The participants were randomly allocated to two groups receiving the drugs Novafen and Ginger. At the beginning of pain, in the two groups 200 mg capsule was given every 6 h for two serial cycles. Pain severity was measured by the visual scale before treatment, 1 h after consuming the drug (for 24 h) and 48 h after the onset of drug.

Results

The mean age of participants was 21.83 ± 2.07 years. It has been reported that the intensity of pain from dysmenorrhea decreased in the Novafen and Ginger groups. Before treatment, the average pain intensity in Novafen and Ginger users were 7.12 ± 2.32 and 7.60 ± 1.84, respectively and after treatment pain intensity decreased to 3.10 ± 2.69 and 2.97 ± 2.69, respectively. Differences between two groups each time showed no statistical significance (p > 0.05).

Conclusion

Both drugs reduced menstrual pain. Ginger as well as Novafen is effective in relieving pain in girls with primary dysmenorrhea . Therefore, treatment with natural herbal medicine, non-synthetic drug, to reduce primary dysmenorrhea is recommended.  相似文献   
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