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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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The aim of this chronic experimental study performed in 16 dogs was to determine the effect of epidural infusion of 0.01% clopheline solution on the morphological and histoenzymological characteristics of spinal ganglion neurons. Daily infusions of clopheline at the dose of 15 mg/kg for 14 days caused a decrease in capillary permeability in the spinal ganglia at the injection site and its increase in the intact areas. This finding suggests the changes in the activity of the microcirculatory bed with a disturbed interaction in capillary-neuron system. Analysis of morphometric parameters has demonstrated the presence of some functional and reversible dystrophic changes in spinal ganglion neurons, which were associated with epidural infusion of both clopheline and isotonic solution of sodium chloride. Determination of the activity of oxidation-reduction enzymes, which reflect the course of aerobic and anaerobic processes in spinal ganglion neurons, has shown no significant differences between the groups of animals infused with or isotonic solution of sodium chloride. In conditions of chronic experiment no significant variations were found in RNA content in ganglionic cells at and outside the sites of infusion of clopheline and of isotonic solution of sodium chloride. 相似文献
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Is the outcome of in-vitro fertilization and embryo transfer treatment improved by spontaneous or surgical drainage of a hydrosalpinx? 总被引:4,自引:7,他引:4
Sowter MC; Akande VA; Williams JA; Hull MG 《Human reproduction (Oxford, England)》1997,12(10):2147-2150
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
6.
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
7.
A. A. Bukreyev V. E. Volchkov V. M. Blinov S. A. Dryga S. V. Netesov 《Archives of virology》1995,140(9):1589-1600
Summary The nucleotide sequence of genomic RNA of Marburg virus strain Popp was determined. Strain Popp was isolated in 1967 during the first filoviral outbreak. The virus was purified from blood of infected guinea pigs in which it had been maintained. The length of the determined sequence was 19112 nucleotides. Amino acid sequences of seven known virion proteins were deduced. Nucleotide and amino acid sequences were compared with those of strain Musoke of Marburg virus isolated in 1980 in Kenya and purified from Vero cells. Homology between nucleotide sequences of two strains was 93.9%. Comparisons revealed conserved and variable regions of the nucleotide and amino acid sequences. The GP, the envelope protein of the virion, was found to be the most variable protein. The greatest differences in the protein were located in the supposedly external part of the molecule. Amino acid substitutions in the L protein, the main component of viral RNA-dependent RNA polymerase, were also distributed extremely non-randomly. It was shown that the non-coding regions of the genome were more variable than the coding ones; 37.6% of nucleotide differences corresponded to the former. 72.6% of nucleotide substitutions located in the coding regions were found to be at the third codon position.Presented in part at the Ninth International Conference on Negative Strand Viruses, Estoril, Portugal, October 2–7, 1994 (Abstract 237), and at IXth International Congress of Virology, Glasgow, Scotland, 8–13 August 1993 (Abstract W52-4). 相似文献
8.
Saroj Neupane M.D. Naga VA Kommuri M.D. Noora Kazanji D.O. Pertha Chowdhury M.D. F.A.C.C. 《Echocardiography (Mount Kisco, N.Y.)》2016,33(11):1788-1789
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
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10.
R A Morey J E Dunsmoor C C Haswell V M Brown A Vora J Weiner D Stjepanovic H R Wagner III VA Mid-Atlantic MIRECC Workgroup K S LaBar 《Translational psychiatry》2015,5(12):e700
Fear conditioning is an established model for investigating posttraumatic stress disorder (PTSD). However, symptom triggers may vaguely resemble the initial traumatic event, differing on a variety of sensory and affective dimensions. We extended the fear-conditioning model to assess generalization of conditioned fear on fear processing neurocircuitry in PTSD. Military veterans (n=67) consisting of PTSD (n=32) and trauma-exposed comparison (n=35) groups underwent functional magnetic resonance imaging during fear conditioning to a low fear-expressing face while a neutral face was explicitly unreinforced. Stimuli that varied along a neutral-to-fearful continuum were presented before conditioning to assess baseline responses, and after conditioning to assess experience-dependent changes in neural activity. Compared with trauma-exposed controls, PTSD patients exhibited greater post-study memory distortion of the fear-conditioned stimulus toward the stimulus expressing the highest fear intensity. PTSD patients exhibited biased neural activation toward high-intensity stimuli in fusiform gyrus (P<0.02), insula (P<0.001), primary visual cortex (P<0.05), locus coeruleus (P<0.04), thalamus (P<0.01), and at the trend level in inferior frontal gyrus (P=0.07). All regions except fusiform were moderated by childhood trauma. Amygdala–calcarine (P=0.01) and amygdala–thalamus (P=0.06) functional connectivity selectively increased in PTSD patients for high-intensity stimuli after conditioning. In contrast, amygdala–ventromedial prefrontal cortex (P=0.04) connectivity selectively increased in trauma-exposed controls compared with PTSD patients for low-intensity stimuli after conditioning, representing safety learning. In summary, fear generalization in PTSD is biased toward stimuli with higher emotional intensity than the original conditioned-fear stimulus. Functional brain differences provide a putative neurobiological model for fear generalization whereby PTSD symptoms are triggered by threat cues that merely resemble the index trauma. 相似文献