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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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Thermal injury is diagnosed by fibrobronchoscopy within the first 5 days after inhalation burn trauma in 73 patients (34% of the total number of patients hospitalized during the last 2 years). Pathological changes of the mucosa with predominant multiple ulceration at different levels of the tracheobronchial tree are detected in 44% patients and in more than 70% patients with acute respiratory deficiency. These changes determine variation and severity of thermal inhalation injury in the patients, and, together with morphofunctional characteristics, provide objective basis for the early diagnostics and prognosis. Translated fromByullelen' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 8, pp. 221–225, August, 1997  相似文献   
4.
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   
5.
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   
6.
Biological properties of 6 variants of monoclonal antibodies (MAb) to Karelian fever virus, a member of the alpha-virus serocomplex Sindbis-WEE, produced by the available hybridomas. The productivity of hybridomas of the "Karel" series in tissue culture and in cultivation as ascitic fluid was evaluated. Among the antibodies analysed, all were specific to envelope proteins, of them 2 were against protein E2 and four against protein E1. Comparison of MCA biologic activity (neutralizing, antihemagglutinating activities, participation in immunofluorescence, EIA, and immune blotting) allows one to distinguish four different hybridomas among them producing specific antibodies differing in their properties.  相似文献   
7.
This paper reports the electro-optical properties of high resistivity nematic liquid crystals sandwiched between ferroelectric polymer films. Interactions between liquid crystals and the film result in a series of interesting optical and electro-optical features. For example, the visualization of ferroelectric domains by means of liquid crystals has been known for decades. However, here we demonstrate that liquid crystals can also reveal the fractal dimension of multi—domain poly(vinylidene fluoride)-based films. Unidirectionally rubbed films made of poly(vinylidene fluoride)-based (PVDF) materials align liquid crystals (LC) homogeneously, with the pretilt angle on the order of 1–2 degrees. This property was implemented in the design of hybrid cells composed of liquid crystals sandwiched between PVDF-based films. The designed PVDF|LC|PVDF cells exhibit tunable electro-optical performance originating from the presence of the PVDF-based films. More specifically, (i) the threshold voltage characterizing the transition of liquid crystals from a planar to a homeotropic state can be tuned by varying the film thickness, and (ii) total fall time (turn-off time) can be controlled by varying the frequency and amplitude of the driving voltage. This frequency dependence of the fall time is strongly pronounced at a relatively high voltage applied across the cell. In the low frequency regime, an increase in the turn-off time can be approximated as a linear function of the applied electric field. An electric-field induced polarization of the PVDF-based films is considered a major reason leading to the afore-mentioned amplitude and frequency dependence of the switching time.

Liquid crystals (LC) can reveal the fractal dimension of multi-domain ferroelectric films (FF) while these films can control the switching time of FF–LC hybrids.  相似文献   
8.
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   
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The prevalence of isolated calf deep vein thrombosis (DVT) in the community setting is relatively unexplored. Confusion remains with regards to its management and contemporary natural history. The purpose of this investigation was to describe the number of cases of calf DVT in the community, use of early management strategies, and rates of venous thromboembolism (VTE) recurrence and major bleeding. The medical records of residents of the Worcester (MA) metropolitan area with ICD-9 codes consistent with potential VTE during 4 study years (1999/2001/2003/2005) were validated by trained nurses. Patient demographic/clinical characteristics, treatment practices, and outcomes were evaluated. Isolated calf DVT was diagnosed in 166 (11.1%) of 1,495 patients with lower extremity DVT. Patients with calf DVT were less likely to be discharged on anticoagulants or with an IVC filter than patients with proximal DVT (84.1 vs. 92.3%). The rates of VTE recurrence and pulmonary embolism did not differ significantly between patients with calf DVT and proximal DVT at 6 months (11.0 vs. 8.7%, 2.6 vs. 1.8%, respectively). Patients with calf DVT had higher adjusted risk of early (14-day) VTE recurrence/extension (OR 2.34, 95% CI 1.01–5.44). Patients with calf DVT had lower rates of major bleeding at 6 months compared to patients with proximal DVT (5.2 vs. 9.3%, P = 0.04). Rates of recurrent VTE and major bleeding following calf DVT in the community are much higher than in randomized clinical trials of patients with proximal or calf DVT. Further study of management strategies for isolated calf DVT is needed.  相似文献   
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