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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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A pilot study was designed to examine whether the outcome of embryo transfer in women with a hydrosalpinx might be improved by surgical drainage of the hydrosalpinx at the time of oocyte collection for in- vitro fertilization treatment. A comparative, controlled but retrospective analysis of the results was performed of all women with infective tubal damage aged <40 years old, who had ovulatory cycles, a normal uterus and a partner with normal spermatozoa. A standardized treatment regimen was used. A maximum of three embryos were transferred. Hydrosalpinx was defined by prior hysterosalpingography and/or laparoscopy with transcervical dye injection. A total of 237 embryo transfer cycles in women with hydrosalpinges (tubal distension not visible in 151, visible but not drained in 30 and drained in 56) were compared with 705 embryo transfer cycles in women with tubal disease but no hydrosalpinx. Results were analysed in the first three cycles but also separately in the first cycle to check for bias. Success rates were higher in the first cycle, but did not significantly influence overall differences. Implantation rates were significantly reduced overall in the hydrosalpinx group (8.0 versus 13.2% for controls; P < 0.001), being 8.3% (P < 0.01) in the subgroup without evident tubal distension and 7.5% (not significant) in the drained hydrosalpinx group. This study shows that tubal damage with distal occlusion is associated with a marked reduction in embryo implantation, even in the absence of obvious fluid distension. Surgical drainage of distended hydrosalpinges appears to offer no benefit.   相似文献   
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目的对十年前后精神分裂症患者用药情况的变化进行调查分析.方法对十年前后两个五年段的各500份符合精神分裂症诊断标准的病历进行回顾性调查,并对各项指标进行对比分析.结果两组折算用药剂量经t检验差异无显著性(P>0.05);两组合并用药、合并抗胆碱药及疗效经χ2检验差异有显著性(P<0.01);十年后非典型抗精神病药物氯氮平在临床上的应用比例明显增大并上升为首位.结论十年前后两组抗精神病药的应用发生了明显变化,疗效好、副作用轻的非典型抗精神病药的应用比例明显增加.  相似文献   
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Occupational exposure to styrene was studied in nine workersof a hand lamination plant in Bohemia. Personal dosimeters wereused to monitor the styrene workplace exposure, and the levelsof styrene in blood and mandelic acid in urine were measured.Blood samples were taken at four occasions during a 7 monthperiod to determine styrene-specific 06-guanine DNA adductsin lymphocytes and granulocytes, DNA strand breaks and hypoxanthineguanine phosphoribosyltransferase (HPRT) mutant frequency inT-lymphocytes. Seven administrative employees in the same factory(factory controls) and eight persons in a research laboratory(laboratory controls) were used as referents. DNA adduct levelsdetermined by the 32P-postlabelling method in lymphocytes oflamina-tors were remarkably constant and significantly higher(P < 0.0001) than in factory controls at all four samplingtimes. HPRT mutant frequencies (MF) measured by the T-cell cloningassay were higher in the laminators (17.5 x10–6, groupmean) than in the factory controls (15.7x10–6, group mean)at three of the four sampling times, but the differences werenot statistically significant. However, a statistically significant(P = 0.021) difference between MF in the laminators (18.0 x10–6,group mean) and laboratory controls (11.8 xl0–6, groupmean) was observed at sampling time 4 (the only sampling timewhen this latter group was studied). This result indicates thatstyrene exposure may induce gene mutation in T-cells in vivo.DNA strand breaks were studied by the ‘Comet assay’at the fourth sampling time. The laminators were found to havesignificantly higher levels of DNA strand breaks than the factorycontrols (P = 0.032 for tail length, TL; P = 0.007 for percentageof DNA in tail, T%; and P = 0.020 for tail moment, TM). A statisticallysignificant correlation was also found between the levels oflymphocyte DNA adducts and all three DNA strand break parameters(TL P = 0.046; T% P = 0.026 and TM P = 0.034). On the contrary,no significant correlations were found between DNA adduct levelsand the HPRT mutant frequencies or between the mutant frequenciesand DNA strand breaks. Taken together, these results add furthersupport to the genotoxic and possibly mutagenic effects of styreneexposure in vivo. However, no simple quantitative relationshipseems to exist between the levels of styrene-induced DNA damageand frequency of HPRT mutation in T-lymphocytes.  相似文献   
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OBJECTIVE: The aim of this study was to clarify the relationship between morphologic changes of the pituitary gland and the genotype of Prophet of Pit-1 (PROP1), a newly discovered gene responsible for congenital combined pituitary hormone deficiency, in a series of eight humans with this disorder. CONCLUSION: Congenital hypoplasia of the anterior pituitary gland is the most common MR imaging finding in patients with combined pituitary hormone deficiency. Our findings suggest a crucial role for PROP1 in pituitary organogenesis as well as anterior pituitary cell differentiation.  相似文献   
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An increase in growth rates of children suffering from growth hormone deficiency (GHD) subjected to recombinant growth hormone treatment (rGHT) was shown to be accompanied by acceleration of metabolic processes that may stimulate oxygen consumption in various organs and tissues. Therefore, oxygen-transporting properties of RBC should undergo considerable changes during the rGHT. The aim of this study was to examine the effects of rGHT on erythrocyte shape and hemoglobin state in GHD children. The level of oxyhemoglobin (Oxy-Hb) in RBC was analyzed by Raman spectroscopy. The RBC count, mean corpuscular hemoglobin (MCH), mean corpuscular volume (MCV) and other parameters were calculated. The blood of eleven treatment-naive prepubertal children with GHD (aged 3–9, median 5.7 years) was examined and compared with control group (aged 5–7; median 6.0 years) at three time points: 0, 3 and 12 months of rGHT. Before rGHT, the MI in GHD children was higher (median 0.48 vs 0.14 p = 0.0018) and the RBC count was lower (median 4.20 vs 4.96 1012 cells/L p = 0.0022) than in control group. After the treatment, cell count in GHD patients did not differ significantly from the control group, but Oxy-Hb level became higher (median 0.64 vs 0.41 p = 0.0075). During rGHT, MCV decreased (median 80.3 vs 83.2 μm3 p = 0.0231). Morphological and functional characteristics of erythrocytes in GHD children were shown to differ significantly from the healthy control group. A twelve-month rGHT partially improved some of the studied parameters but Oxy-Hb level and echinocyte count remained high.  相似文献   
9.
Development of left ventricular pseudoaneurysm is a rare complication of mitral valve surgery and requires urgent surgical intervention. We describe a case of pseudoaneurysm of membranous septum following repeat mitral valve replacement with the use of multimodality imaging.  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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