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11.
Apnea is a common complication of respiratory syncytial virus (RSV) infection in young infants. The purpose of this study was to determine whether this infection affects apnea triggered by sensorineural stimulation in weanling rats. We also studied which neurotransmitters are involved in this response and whether passive prophylaxis with a specific neutralizing antibody (palivizumab) confers protection against it. Weanling rats were inoculated intranasally with RSV, adenovirus, or virus-free medium. Changes in respiratory rate and apnea in response to nerve stimulation with increasing doses of capsaicin were measured by plethysmography. Capsaicin-induced apnea was significantly longer in RSV-infected rats at postinoculation days 2 (upper airways infection) and 5 (lower airways infection), and apnea-related mortality occurred only in the RSV-infected group. Reduction in the duration of apnea was observed after selective inhibition of central gamma-aminobutyric acid (GABA) type A receptors and neurokinin type 1 receptors for substance P. Prophylactic palivizumab protected against apnea and apnea-related mortality. These results suggest that sensorineural stimulation during RSV infection is associated with the development of apnea and apnea-related death in early life, whose mechanism involves the release of GABA acting on central GABA type A receptors and substance P acting on neurokinin type 1 receptors.  相似文献   
12.
Specific regions of the human occipito-temporal cortex are consistently activated in functional imaging studies of face processing. To understand the contribution of these regions to face processing, we examined the pattern of fMRI activation in four congenital prosopagnosic (CP) individuals who are markedly impaired at face processing despite normal vision and intelligence, and with no evidence of brain damage. These individuals evinced a normal pattern of fMRI activation in the fusiform gyrus (FFA) and in other ventral occipito-temporal areas, in response to faces, buildings, and other objects, shown both as line drawings in detection and discrimination tasks and under more naturalistic testing conditions when no task was required. CP individuals also showed normal adaptation levels in a block-design adaptation experiment and, like control subjects, exhibited evidence of global face representation in the FFA. The absence of a BOLD-behavioral correlation (profound behavioral deficit, normal face-related activation in the ventral occipito-temporal cortex) challenges existing accounts of face representation, and suggests that activation in these cortical regions per se is not sufficient to ensure intact face processing.  相似文献   
13.
PURPOSE: This paper describes the role of MR imaging in the identification of the different macroscopic patterns of lipoma arborescens. MATERIALS AND METHODS: Between June 1995 and January 2004, a total of 6387 MR examinations of the knee were retrospectively assessed for the presence of lipoma arborescens. The MR examinations were performed using a superconductive 0.5 T MR unit with a transmitting/ receiving coil dedicated for the extremities. The MR images were acquired with SE T1-weighted, GE T2-weighted and STIR sequences in sagittal, coronal and axial planes with 3-mm thickness and 1-mm gap. RESULTS: Lipoma arborescens was identified in 9 patients (mean age: 36 years). In 2/9 cases a localized lipoma arborescens was detected as a well-marginated single nodule on the suprapatellar bursa without irregularity or synovial hyperplasia. In the remaining 7 cases diffuse lipoma arborescens was identified on the wall of the suprapatellar bursa. In one case of diffuse lipoma arborescens there was involvement of both knees. In all cases the MR findings were verified at surgery and the final diagnosis was made by histological examination. CONCLUSIONS: MR imaging shows a high accuracy in the identification and characterization of lipoma arborescens, due to its multiplanar capabilities and high contrast resolution. MRI allows correct evaluation of size and grade, accurate treatment planning and effective follow-up, avoiding the need for synovial biopsy.  相似文献   
14.
AIM: To investigate the diagnostic accuracy of two different protocols for image evaluation used in multislice computed tomography coronary angiography (MSCT-CA). MATERIALS AND METHODS: Sixty patients with suspected coronary artery disease undergoing conventional coronary angiography (CA) were enrolled for MSCT-CA. All patients underwent 16-row MSCT (Sensation 16, Siemens, Germany) with the following parameters: detector rows 16, collimation 0.75 mm, gantry rotation time 375 ms. Two independent observers assessed the images for significant stenosis using a a protocol with standard projections and a three-dimensional protocol. The diagnostic accuracy for both methods was calculated using quantitative CA as a reference standard. RESULTS: The sensitivity, specificity, negative predictive value and positive predictive value obtained with the conventional projection protocol and with three-dimensional protocol were: 54% and 93%, 97% and 97%, 76% and 86%, 92% and 99%, respectively. CONCLUSIONS: Conventional projections in the assessment of MSCT-CA provide insufficient diagnostic accuracy compared with three-dimensional processing.  相似文献   
15.
The prevalence of benign focal liver lesions (BFLL) is high both in the general population and in patients with known malignancies. The gray-scale ultrasound (US) technique is usually the first-line imaging modality used in the radiological workup of such lesions, but unfortunately it lacks specificity. Furthermore, Doppler examination may often be unsatisfactory owing to motion artefacts, or when small or deeply located lesions are evaluated. Recently, microbubble-based contrast agents used in combination with gray-scale US techniques, which are very sensitive to nonlinear behavior of microbubbles, have led to a better depiction of both microvasculature and macrovasculature of focal hepatic masses, thus improving the reliability of using US in the assessment of liver tumors. This review illustrates the spectrum of enhancement patterns of BFLL on contrast-enhanced ultrasonography with SonoVue, a second-generation microbubble-based contrast agent.This paper is based on a work accepted for presentation as a scientific paper at the Scientific Assembly and Annual Meeting of the ECR 2004.  相似文献   
16.
The aim of this study was to describe gray-scale appearance of liver parenchyma and focal nodular hyperplasia (FNH) by pulse inversion (PI) ultrasound (US) at baseline and after contrast agent administration in patients with normal and fatty liver. Sixteen consecutive patients (12 women, 4 men) with 29 previously diagnosed FNHs (15 of 29 located in normal liver and 14 of 29 in fatty liver) underwent PI US before and after SH U 508A (Levovist) injection. Signal intensity values were measured within the FNHs and the adjacent liver parenchyma in selected images. Baseline echogenicity of fatty liver was higher (15.19±2.90 dB±SD) than normal liver (10.91±3.15 dB±SD; p<0.001). After Levovist administration, normal livers (7 of 16) showed a statistically significant increase of echogenicity (16.59±3.81 dB±SD; p<0.001) in comparison with fatty livers (9 of 16; 15.75±3.12 dB±SD). The FNHs located in normal liver showed baseline echogenicity higher (12.29±3.22 dB±SD) than that of FNHs arising in fatty liver (7.06±2.43 dB±SD; p<0.001). After Levovist administration, FNHs located in normal liver showed a statistically significant increase of echogenicity (25.30±4.62 dB±SD) in comparison with FNHs located in fatty liver (13.58±3.54 dB±SD; p<0.001); the latter always showed mean values of echogenicity lower than surrounding liver parenchyma. In our series decreased contrast-enhancement pattern of both fatty liver and FNHs located in fatty liver was the most prominent finding when Levovist is administered. Contrast washout was a distinctive feature of FNH arising from the fatty liver.This paper has been accepted for presentation as a scientific paper at the Scientific Assembly and Annual Meeting of the ECR 2003.  相似文献   
17.
The objective of this paper was to identify risk factors for nontyphoid Salmonella bacteremia by making a retrospective chart review of 39 patients with nontyphoid Salmonella bacteremia. The control group included 30 patients with positive Salmonella stool culture (gastroenteritis group). Demographic factors, presenting signs and symptoms, antimicrobial treatment before admission, and microbiologic results were recorded. Nine patients (23%) were excluded owing to recognized risk factors for development of extraintestinal disease. Seventeen cases (57%) occurred during summer time, whereas the gastroenteritis group had a less seasonal tendency. Eighty percent of the patients with Salmonella bacteremia had a previous history of diarrhea. At admission more patients in the bacteremia group were febrile and had leukocytosis (73% vs 33% and 37% vs 20%, respectively). More patients in the bacteremia group had previous antibiotic treatment (57% vs 20%, p<0.01). The Salmonella types were mainly C and D in the bacteremia group (40% each), and B and C in the gastroenteritis group (26% and 52%, respectively). The risk factors for Salmonella bacteremia in previously healthy children include warm season, previous gastrointestinal illness, and preexposure to antibiotics.  相似文献   
18.
OBJECTIVES: Women with breast cancer are at risk for elevated depression, anxiety, and decreased natural killer (NK) cell number. Stress has been linked to increased tumor development by decreasing NK cell activity. The objectives of this study included examining massage therapy for women with breast cancer for (1) improving mood and biological measures associated with mood enhancement (serotonin, dopamine), (2) reducing stress and stress hormone levels, and (3) boosting immune measures. METHODS: Thirty-four women (M age=53) diagnosed with Stage 1 or 2 breast cancer were randomly assigned postsurgery to a massage therapy group (to receive 30-min massages three times per week for 5 weeks) or a control group. The massage consisted of stroking, squeezing, and stretching techniques to the head, arms, legs/feet, and back. On the first and last day of the study, the women were assessed on (1) immediate effects measures of anxiety, depressed mood, and vigor and (2) longer term effects on depression, anxiety and hostility, functioning, body image, and avoidant versus intrusive coping style, in addition to urinary catecholamines (norepinephrine, epinephrine, and dopamine) and serotonin levels. A subset of 27 women (n=15 massage) had blood drawn to assay immune measures. RESULTS: The immediate massage therapy effects included reduced anxiety, depressed mood, and anger. The longer term massage effects included reduced depression and hostility and increased urinary dopamine, serotonin values, NK cell number, and lymphocytes. CONCLUSIONS: Women with Stage 1 and 2 breast cancer may benefit from thrice-weekly massage therapy for reducing depressed mood, anxiety, and anger and for enhancing dopamine, serotonin, and NK cell number and lymphocytes.  相似文献   
19.
A large amount of evidence shows that the subjective evaluation of health is a predictor of survival in many different populations. Subjective health (SH) is measured using different types of measures such as a general evaluation of health or a comparative evaluation of health. The aim of this study was to compare the prediction of survival by two measures of SH (a general measure and an age-related measure) and evaluate the association with other variables in an elderly population. The baseline survey was conducted during 1994, covering 1138 men and women aged over 70. The survival status was ascertained 7 years later. After adjustment for age, sex, education, marital status, perceived socioeconomic status and presence of diseases the two SH measures were found to be predictors of mortality, but only in men. In men, there was no significant difference between the two types of SH measures in their prediction of mortality. Also in men, when there was only one or no disease, being married had a protective effect compared with not being married when both types of SH measures were used. In elderly women, the association between the two types of SH and survival diminished after adjusting for the various variables. However, the general SH measure may be the preferable measure to use when needed. Education in women was associated with mortality only via the age-related SH measure.  相似文献   
20.
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