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991.
Mesenchymal hamartoma is a rare and benign tumor.. Representing 5 to 8 % of children's hepatic tumors, it is rarely described in adults. Authors report a new case of hepatic mesenchymal hamartoma in a 21-year-old woman, diagnosed after a sudden onser of clinical and biological cholestasis. Abdominal US and CTscan exminations showed a medial liver tumor with cystic formations suggestive of a hydatid cyst. The diagnosis of hepatic mesenchymal hamartoma was based onn hitology of the resected liver specimen. Radiological findings can suggest the diagnosis but only histology can confirm it. Treatment is surgical involving in most of the cases; a wide hepatic resection because of the size of the tumor. Progosis is excellent when complete exeresis is possible.  相似文献   
992.
Contribution of serum Cyfra 21-1 in nasopharyngeal carcinoma in Tunisia   总被引:1,自引:0,他引:1  
Cyfra 21-1 is a recognised marker for epidermoid lung and head and neck carcinomas oriented to the cytokeratin 19 that is expressed particularly in malignant epithelial cells. The aims of this study were to evaluate the importance of the use of this marker in nasopharyngeal carcinoma (NPC). Our prospective study interested 41 patients (33M/8F) with a mean age of 44 years (13 to 70) with 8 of them aged less than 30 years, presenting a nasopharyngeal carcinoma histologically confirmed from September 1999 to March 2000 and 45 healthy controls without evidence neoplasm. Undifferentiated forms represent 90.2% of cases and lesions are staged T2, T3 and T4 in 2.4%, 36.6% and 61% of cases, while N1, N2 and N3 represent 9.8%, 26.8% and 41.5% of cases. A blood sample was collected from each patient and control before any treatment, as well as controls to measure Cyfra 21-1 by immunoenzymatic assay, 2 groups of patients were selected after a period varying from 4 to 37 months with a median of 29 months: 27 patients with favourable evolution (without evidence of disease after initial treatment), 12 patients with non favourable evolution (1 death, 2 cases of loco-regional relapse and 9 patients with metastatic disease). 2 patients were lost to follow-up. The results showed that the mean serum Cyfra 21-1 values were significantly higher in patients with NPC than those in controls (p = 0.001). A significant correlation was found between the serum Cyfra 21-1 level before treatment and the clinical outcome of patients (p = 0.0009). Patients having a favourable evolution have the lowest level. Seric level of Cyfra 21-1 at diagnosis of NPC may play a predictive role to evaluate the risk of metastatic disease and prognosis.  相似文献   
993.
PURPOSE: To compare the effects of passive versus active recovery on muscle oxygenation and on the time to exhaustion for high-intensity intermittent exercises. METHODS: Twelve male subjects performed a graded test and two intermittent exercises to exhaustion. The intermittent exercises (15 s) were alternated with recovery periods (15 s), which were either passive or active recovery at 40% of .VO2max. Oxyhemoglobin was evaluated by near-infrared spectroscopy during the two intermittent exercises. RESULTS: Time to exhaustion for intermittent exercise alternated with passive recovery (962 +/- 314 s) was significantly longer (P < 0.001) than with active recovery (427 +/- 118 s). The mean metabolic power during intermittent exercise alternated with passive recovery (48.9 +/- 4.9 mL.kg-1.min-1) was significantly lower (P < 0.001) than during intermittent exercise alternated with active recovery (52.6 +/- 4.6 mL.kg-1.min-1). The mean rate of decrease in oxyhemoglobin during intermittent exercises alternated with passive recovery (2.9 +/- 2.4%.s-1) was significantly slower (P < 0.001) than during intermittent exercises alternated with active recovery (7.8 +/- 3.4%.s-1), and both were negatively correlated with the times to exhaustion (r = 0.67, P < 0.05 and r = 0.81, P < 0.05, respectively). CONCLUSION: The longer time to exhaustion for intermittent exercise alternated with passive recovery could be linked to lower metabolic power. As intermittent exercise alternated with passive recovery is characterized by a slower decline in oxyhemoglobin than during intermittent exercise alternated with active recovery at 40% of .VO2max, it may also allow a higher reoxygenation of myoglobin and a higher phosphorylcreatine resynthesis, and thus contribute to a longer time to exhaustion.  相似文献   
994.
OBJECTIVE: The aim of the study is to evaluate the role of computed tomography (CT)-guided percutaneous drainage in the management of solitary splenic abscesses. MATERIALS AND METHODS: Sonography and CT were used in the initial diagnosis of splenic abscess in patients with vague left upper quadrant pain and/or fever. Solitary splenic abscesses of nine male patients whose ages varied between 21 and 27 years (mean age: 24.7 years) were percutaneously drained under CT guidance. Puncture with 18-gauge Chiba needles and coaxial guidewire technique was used for insertion of six or eight French pigtail catheters. Antibiotics in accordance with the microbiological results were also given adjuvant to drainage. Follow-up examinations were performed by sonography, daily for the first week and weekly for the next 7 weeks, and by CT at the end of first, fourth and eighth weeks. RESULTS: All patients tolerated the intervention well, except for one complicating with splenic rupture and hemorrhage, who underwent emergency splenectomy. The remaining eight patients recovered within 4 weeks without any splenic sequela. A mean of 3.9 days was needed before removing the drainage catheter based on regression criteria. DISCUSSION AND CONCLUSION: CT-guided percutaneous drainage of splenic abscesses may be proven effective and is superior to splenectomy in selected cases, as it preserves host immunity.  相似文献   
995.
INTRODUCTION: Histologic examination of circumferential margins is an important predictor of local and distant relapse in non-radiated rectal cancer. However, for patients who received preoperative chemoradiotherapy this role has not yet been addressed. METHODS: From January 1995 to December 1997, 61 patients with rectal adenocarcinoma located between 0 and 10 cm from anal verge with invasion into perirectal fat assessed by rectal ultrasound were included. All patients received 45 Gy + bolus infusion of 5-FU (450 mg/m(2)/days 1-5, 28-33 of RT); 4-6 weeks later, surgery was performed. Circumferential margin was assessed (<2 mm was considered as positive). Five-year survival was calculated by Kaplan-Meier method and comparison of groups with log-rank test. Multivariate Cox regression analysis was performed to find risk factors affecting local control and survival. RESULTS: There were 35 males and 26 females, mean age 60.3 years. Twelve patients (19.7%) had circumferential margin involvement. Median follow-up was 44 months. Overall local recurrence was observed in 6 of 61 patients (9.8%); in patients without circumferential margin involvement this was 8%, whereas it was 16% in those with circumferential margin involvement (P = 0.33). Distant recurrence was observed in 22% of patients without circumferential margin involvement; conversely, it was 58.3% in those with involvement (P = 0.02). Five-year survival of patients without circumferential resection involvement margin was 81%, while it was 42% in patients with circumferential involvement (P = 0.006). CONCLUSIONS: In patients with rectal cancer treated by preoperative chemoradiation plus total mesorectal excision (TME) and sphincter saving surgery, circumferential margin involvement is associated with high incidence of distant recurrence and cancer-related death.  相似文献   
996.
The prevalence of overweight and obese children is increasing, a tendency that can be expected to increase the risk of adverse outcomes in adulthood. The aim of this study was to determine if prenatal exposure to alcohol, cigarettes, and street drugs would be associated with differences in body mass index (BMI) in childhood and adolescence in offspring from families at high and low genetic risk for developing alcohol dependence. Annual follow-up of offspring (N = 288) provided 1200 height and weight assessments for analysis. Maternal substance use data were available for 235 offspring from families stratified for familial/genetic risk for alcohol dependence (high or low risk), providing the opportunity to assess prenatal exposure and familial/genetic risk in relation to BMI in the offspring. When data were grouped by the presence or absence of any prenatal cigarette exposure, a significant difference in offspring BMI was seen for 8- to 11-year-olds. Significant group differences were also seen at ages 12-15 and 16-18 years. A dose-response relationship between cigarette use by the mother and offspring BMI was also seen. With the strong tendency for individuals who are overweight in childhood and adolescence to become overweight adults, prenatal exposure to nicotine may be a harbinger of increased risk for numerous adult-onset, weight-related health problems.  相似文献   
997.
Biological evidence supports a role of aromatase and butyrilcholinesterase (BCHE) enzymes in the disruption of the cholinergic neurotransmission observed in Alzheimer's disease (AD). Estrogens may reduce the risk of AD through enhancing or preserving cholinergic neurotransmission, and aromatase, the product of the CYP19 gene, is a critical enzyme in the peripheral synthesis of estrogens. BCHE is a hydrolytic enzyme associated with acetylcholine synaptic degradation, and the BCHE K genetic variant confers some protective effect for AD by reducing the activity of the enzyme. We investigated whether a 5'-UTR CYP19 polymorphism and the BCHE K variant might be responsible for susceptibility to AD by studying a clinically well-defined group of 187 sporadic AD patients and 172 control subjects from a Spanish population. We have shown that the CYP19 C/C genotype is overrepresented in AD patients who carry the BCHE non-K allele when compared with controls (OR=1.85, p=0.03). Our findings suggest that the CYP19 and BCHE polymorphisms may interact in determining the risk of AD.  相似文献   
998.
Kirouac GJ  Parsons MP  Li S 《Brain research》2005,1059(2):179-188
The paraventricular nucleus of the thalamus (PVT) is a midline thalamic nucleus with projections to limbic forebrain areas such as the nucleus accumbens and amygdala. The orexin (hypocretin) peptides are synthesized in hypothalamic neurons that project throughout the CNS. The present experiments were done to describe the extent of orexin fiber innervation of the PVT in comparison to other midline and intralaminar thalamic nuclei and to establish the location and proportion of orexin neurons innervating the PVT. All aspects of the anteroposterior PVT were found to be densely innervated by orexin fibers with numerous enlargements that also stained for synaptophysin, a marker for synaptic vesicle protein associated with pre-synaptic sites. Small discrete injections of cholera toxin B into the PVT of rats resulted in the retrograde labeling of a relatively small number of orexin neurons in the medial and lateral hypothalamus. The results also showed a lack of topographical organization among orexin neurons projecting to the PVT. Previous studies indicate that orexin neurons and neurons in the PVT appear to be most active during periods of arousal. Therefore, orexin neurons and their projections to the PVT may be part of a limbic forebrain arousal system.  相似文献   
999.
犬结肠黏膜与颊黏膜移植到膀胱后的组织病理学变化   总被引:1,自引:0,他引:1  
Xu YM  Qiao Y  Sa YL  Zhang HX  Zhang XR  zhang J  Chen R  Xie H  Si JM  Li T 《中华医学杂志》2004,84(17):1418-1420
颊黏膜作为一种尿道替代物已在临床上广泛应用,疗效显著。然而,由于颊黏膜材源有限,较难用于10cm以上的长段尿道狭窄的修复,必须选用其他组织替代。近几年来,我们进行犬的结肠黏膜替代尿道的实验研究和将结肠黏膜用于10cm以上较长段尿道狭窄或闭锁修复的临床初步研究,近期效果较好。但是结肠黏膜是否能与颊黏膜一样作为理想的尿道替代物尚不清楚,我们将结肠黏膜与颊黏膜同时移植到膀胱,观察两者在尿液中长期浸泡后的组织病理学变化,并比较两者的差异,从而确定结肠黏膜是否能作为较理想的尿道的替代物。  相似文献   
1000.
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