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1.
Neuroimaging in Pineal Tumors   总被引:4,自引:0,他引:4  
F Reis  MD  AV Faria  MD  PhD  VA Zanardi  MD  PhD  JR Menezes  MD  F Cendes  MD  PhD  LS Queiroz  MD  PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread.  相似文献   
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3.
Myo-inositol transport in the central nervous system   总被引:18,自引:0,他引:18  
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4.
In this study we used a novel technique to reveal both longitudinal and transverse differentiation within mammalian mitotic chromosomes. Structural changes in chromosomes that we term ‘differential decondensation’ were produced in cells that were first incubated in hypotonic medium (15% Hanks’ solution), then adapted to normotonic conditions and thereafter exposed to a second short hypotonic shock. Such a double hypotonic treatment (DHT) is not critical for cell viability, but considerably elongates the G2 phase of the cell cycle. Giemsa staining of differentially decondensed chromosomes corresponds to standard G-banding, but does not need the standard post-fixation treatment. Using ‘dynamic’ BrdU banding, we show that such ‘differential’ staining is a result of differential resistance of the R- and G-bands to DHT. Thus, early-replicating foci, markers of R-bands, are localized in the peripheral chromatin halo, whereas late-replicating foci, corresponding to G-bands, remain associated with the axial regions of chromatids. Remarkably, despite these major changes in the structure of the chromosomal bands, the replication foci still preserve their discrete structure.  相似文献   
5.
Biphasic modification of bacterial bioluminescence by human serum was revealed: bioluminescence was inhibited at high concentrations of the serum and stimulated at low concentrations. Effects of temperature and duration of exposure on bioluminescence manifested in stimulation of the inhibitory effect at higher temperature and longer exposure. The degree of inhibition of bioluminescence under in the presence of serum depends on species characteristics of the microorganism and nature of the luminescent system. Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 138, No. 9, pp. 311–315, September, 2004  相似文献   
6.

Purpose

Uncertainties remain regarding the clinical efficacy of ovarian tissue cryopreservation and grafting. We report a retrospective analysis of reproductive outcomes and lessons learnt following 55 ovarian tissue transplant procedures at our center from 2006 to 2019.

Methods

We analyzed variables related to graft success such as tissue volume, follicular density, total follicular volume, and age on the duration of graft function.

Results

Follicular density and total follicular volume correlate positively with duration of graft function. All clinical pregnancies in our cohort occurred in women who were aged 35 or less at the time of ovarian tissue cryopreservation.

Conclusion

Graft success, as determined by eventual pregnancy and the longevity of graft function, may be impacted by factors including age at cryopreservation, follicular density, and total follicular volume.
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8.
Bulletin of Experimental Biology and Medicine - We studied ntimicrobial activity of L. plantarum strain against different pathogens: Escherichia coli, Pseudomonas aeruginosa, Streptococcus...  相似文献   
9.
Labial adhesions are usually seen in early childhood or in the postmenopausal years, but this clinical entity is rarely seen in the reproductive years. We report a case of labial adhesion with acute urinary retention secondary to Bartholin's abscess in a reproductive‐aged woman with normal menstrual periods. We emphasize the possible occurrence of labial adhesion following Bartholin's abscess in the reproductive years with normal estrogen levels.  相似文献   
10.
Isolated GH deficiency (IGHD) is characterized by genetic heterogeneity, both in familial and sporadic cases. To determine if this statement can be applied to the Russian population, we performed screening for mutations in the GH-1 gene in children living in Russia with IGHD. Twenty-eight children from 26 families with total IGHD were studied. DNA fragments, covering each of four (2-5) exons of GH-1 were amplified using PCR. Single-strand conformation polymorphism analysis followed by direct DNA sequencing identified five heterozygous mutations of splicing in intron 2, intron 3, and exon 4 of GH-1; three of them were not previously reported. We concentrated here on dominant-negative mutations causing IGHD type II, which were as follows: 1) A>T transversion of the second base of the 3'-acceptor splice site of intron 2 (IVS2 -2A>T); 2) T>C transition of the second base of the 5'-donor splice site of intron 3 (IVS3 +2T>C); 3) G>A transition of the first base of the 5'-donor splice site of intron 3 (IVS3 +1G>A). Our data indicate allelic heterogeneity of IGHD type II (IGHD II). However, all mutations in Russian IGHD II patients affect splicing, a striking difference from the mutation spectrum of other IGHD forms. The IVS2 -2A>T mutation is the first identified mutation in intron 2 of GH-1. The 5'-donor splice site of intron 3 of GH-1 is a mutational hot spot, and the IVS3 +1G>A mutation can be considered to be a common molecular defect in IGHD II in Russian patients.  相似文献   
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