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71.
Postnatal outcome of fetal cardiac echogenic foci.   总被引:1,自引:0,他引:1  
BACKGROUND AND PURPOSE: Cardiac echogenic foci are found frequently during fetal echocardiographic investigations and may be related to increased mineralization of the papillary muscles. However, data from postnatal follow-up are limited. This study investigated the clinical characteristics and postnatal echocardiographic findings in infants with cardiac echogenic foci identified prenatally. METHODS: Between March 1995 and April 1998, 43 fetuses were noted to have cardiac echogenic foci during the second trimester. Postnatal evaluation was completed for 20 of these 43 fetuses. No other congenital malformations were noted during the fetal stage or after birth. Postnatal echocardiography was performed from 17 months to 4 years and 7 months after birth. RESULTS: Seven (35%) infants had persistent cardiac echogenic foci. However, only one had mild mitral valve prolapse without mitral regurgitation. All fetuses had left ventricular (LV) foci and three also had right ventricular (RV) foci. One infant who had a LV focus prenatally was noted to have a RV focus on postnatal follow-up. Among the three infants with prenatal biventricular involvement, only one had biventricular involvement on postnatal follow-up. Other cardiac echogenic foci had disappeared in all infants. The probability of persistence of foci decreased with age and reached 50% at the age of 4 years and 4 months. Thereafter, cardiac echogenic foci tended to regress and only 11% of infants had persistence at the last follow-up. No significant difference was found in the rate of persistence between children with univentricular foci and those with biventricular foci. CONCLUSIONS: Although some fetal cardiac echogenic foci may persist after birth, fetal echogenic foci were not associated with significant intracardiac or extracardiac anomalies.  相似文献   
72.
PURPOSE: The purpose of this study was to profile methylation alterations of CpG islands in ovarian tumors and to identify candidate markers for diagnosis and prognosis of the disease. EXPERIMENTAL DESIGN: A global analysis of DNA methylation using a novel microarray approach called differential methylation hybridization was performed on 19 patients with stage III and IV ovarian carcinomas. RESULTS: Hierarchical clustering identified two groups of patients with distinct methylation profiles. Tumors from group 1 contained high levels of concurrent methylation, whereas group 2 tumors had lower tumor methylation levels. The duration of progression-free survival after chemotherapy was significantly shorter for patients in group 1 compared with group 2 (P < 0.001). Differential methylation in tumors was independently confirmed by methylation-specific PCR. CONCLUSIONS: The data suggest that a higher degree of CpG island methylation is associated with early disease recurrence after chemotherapy. The differential methylation hybridization assay also identified a select group of CpG island loci that are potentially useful as epigenetic markers for predicting treatment outcome in ovarian cancer patients.  相似文献   
73.
Background: Forty percent of patients with colorectal cancer develop mutations in the K-ras gene.Objective: Our objective was to evaluate whether the presence of c-K-ras gene mutations is a useful tumor-response marker in patients with locally advanced rectal cancer treated with preoperative chemoradiotherapy.Material and Methods: Thirty seven patients with locally advanced rectal cancer were treated with preoperative chemoradiotherapy. Four to six weeks later, surgery was performed. Specimens were classified according to the UICC-AJC classification. A segment of the tumor was obtained to analyze specific c-K-ras gene mutations. Restriction fragment length polymorphism (RFLP) and single strand confirmation polymorphism (SSCP) techniques were used with a set of probes to detect specific c-K-ras mutations in codons 12, 13, and 61. The 37 patients were divided into Group A (with mutations) and Group B (without mutations).Results: All 37 patients completed the scheduled treatment. Group A consisted of 12 patients, whose tumors were classified and specific c-K-ras mutations were located as follows: eight in codon 12, two in codon 13, and one in codon 61. Group B consisted of 25 patients. The tumors were classified and there were more early-stage tumors in Group A, whereas in Group B there were more advanced-stage tumors (P 5 .05, respectively). The mean follow-up was 36.2 6 18.3 months. All Group A patients survived, whereas 8 of the 25 patients in Group B died due to progressive metastatic disease. Survival in Group A was 100%, whereas in Group B it was 59% (P 5 .03).Conclusions: The presence of specific c-K-ras mutations is an indicator of tumor response in patients with locally advanced rectal cancer treated with preoperative chemoradiotherapy and surgery. Therefore, responding patients may be more amenable to less radical surgical procedures based on c-K-ras mutations.  相似文献   
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This study of etoposide in thyroid cancer was designed to determine the activity and toxicity of etoposide in a variety of inoperable, thyroid hormone insensitive, and radio-iodine resistant primary cancers of the thyroid. The patients were required to have an ECOG performance status of at least 3 and no previous exposure to chemotherapy. The etoposide was given at a dose of 140 mg/m2 daily for 3 days and every 3 weeks until progression. The study was closed after 18 months because of poor accrual. There were no responses seen among the 10 patients accrued. The toxicity was primarily hematologic. There was no evidence of activity of etoposide in thyroid carcinoma, although this study lacked significant power because of the poor accrual.  相似文献   
77.
Early Onset Parkinson's Disease (EOPD) is characterized by selective degeneration of nigrostriatal dopaminergic neurons and a marked response to levodopa. However, at present, few methods are available as diagnostic tools for EOPD except for 18F-DOPA PET. In addition, little is known about the correlation between clinical severity, neuroimaging grading and genetic susceptibility. In the present study, 99mTc-TRODAT-1 SPECT and brain MRI were used to identify 30 cases of non-familial EOPD from a Chinese cohort of 230. All 30 PD patients had an age of onset of less than 55 years (mean age at onset, 41.5+/-9.3 years). Each of the 30 EOPD cases was sub-classified into one of five stages based on the 99mTc-TRODAT-1 SPECT findings. In the early stages of PD (stages 1 and 2), a lower uptake of 99mTc-TRODAT-1 in the putamen was found, while uptake in the caudate nucleus was normal. In the latter stages (stages 3, 4, 5), 24 patients revealed a diffuse and uniform loss of 99mTc-TRODAT-1 uptake in the putamen and the caudate nucleus. Further, in conventional genetic studies of the 30 patients, six novel mutations were found in the Parkin gene, and these included five heterozygous point mutations (C441R, Q311H, V258M, C212G, and S193I) and one homozygous deletion (exon 10-12). Known polymorphisms (Ser167Asn, Val380Leu) were also found in a number of patients. However, gene dosage analysis did not reveal any compound heterozygous mutations in these 30 patients using quantitative duplex PCR. This is the first study to examine EOPD patients of Chinese ethnic background (not exhibiting a definite familial trait), to offer a complete genetic analysis of the Parkin gene, and to correlate clinical stages of the disease with dopamine re-uptake.  相似文献   
78.
BACKGROUND AND PURPOSE: Hyperintense putaminal rim (HPR) on the T2-weighted imaging, which has been observed in our daily practice while reading 3T brain images, has been described as a finding typical of multiple system atrophy (MSA). We hypothesized that the HPR sign is not an exclusive hallmark of MSA at a high magnetic field strength, but rather may be a normal finding. METHODS: Ten consecutive clinically healthy age-matched adults who showed recognizable HPR at 3T were subsequently examined on a 1.5T imaging system within 2 hours. MR examination included axial T2-weighted fast spin-echo (FSE), fluid attenuated inversion recovery (FLAIR) on a 3T scanner, and equivalent T2-weighted FSE at 1.5T. MR images were obtained parallel to the intercommissural plane. All the images were interpreted by 2 experienced neuroradiologists. RESULTS: All 10 subjects (3 men and 7 women; aged 52 +/- 6.1 years [range, 44-61 years], expressed as mean +/- SD) with the positive HPR sign on axial T2-weighted FSE at 3T had negative findings at 1.5T. Such hyperintense rim was also vague or absent on the 3T-FLAIR images. CONCLUSION: Our data suggest that the HPR at 3T scans is a nonspecific, normal finding. FLAIR may be helpful in discriminating between normal subjects and patients with MSA in case of isolated HPR at 3T.  相似文献   
79.
The authors report 3 cases of cysts of the tunica albuginea. Scrotal ultrasonography facilitates preoperative diagnosis and helps to avoid orchiectomy or to prevent unnecessary surgery.  相似文献   
80.
Recent fMRI studies are of interest in exploring long-range interactions between different brain structures and the functional activation of specific brain regions by known neuroanatomical pathways. One of the experimental approaches requires the invasive implantation of an intracranial electrode to excite specific brain structures. In the present report, we describe a procedure for the production of a glass-coated carbon fiber electrode and the use of this electrode for direct activation of the brain in fMRI studies. The glass-coated carbon fiber microelectrode was implanted in the medial thalamus of anaesthetized rats and T2*-weighted gradient echo images in the sagittal plane obtained on a 4.7 T system (Biospec BMT 47/40) during electrical stimulation of the medial thalamus. The image quality obtained using this electrode was acceptable without reduction of the signal-to-noise ratio and image distortion. Cross-correlation analysis showed that the signal intensities of activated areas in the ipsilateral anterior cingulate cortex were significantly increased by about 4-5% during medial thalamus stimulation. The present study shows that glass-coated carbon fiber electrodes are suitable for fMRI studies and can be used to investigate functional thalamocingulate activation.  相似文献   
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