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81.
This paper addresses the cost of childhood and adolescent obesity on the United States healthcare system. The specific focus is the prevention and treatment of obesity in children. The cost of prevention and treatment programs are considered as well as other costs due to further complications caused by obesity in children and adolescents. Examples of health expenditures in Canada are used to exemplify the prevalence of obesity and its effect on healthcare expenditures.  相似文献   
82.
A forced-choice discrimination paradigm was used in two experiments, to evaluate retrograde and anterograde amnesia in rats after hippocampal ablation. In a within-subjects design (Experiment 1), rats were trained on a set of 10 olfactory discriminations 4 weeks before surgery and on a separate set of 10 discriminations 1 week before surgery. In a mixed design (Experiment 2), rats were trained on olfactory discriminations in one of three conditions: condition 1 (10 discriminations at 4 weeks before surgery); condition 2 (10 discriminations at 1 week before surgery); or condition 3 (10 discriminations at 4 weeks before surgery and 10 discriminations at 1 week before surgery). Discriminations in both experiments were rapidly learned, requiring 7-10 trials to reach criterion. After training, half of the rats in each condition received bilateral neurotoxic lesions of the hippocampus, and the other half received sham surgery. One week after surgery, all rats were given a retention test, consisting of a single critical trial for each discrimination. In both experiments, rats with selective hippocampal lesions exhibited preserved retention of these olfactory discriminations with no observable retention gradient. A postoperative acquisition test for two new discriminations indicated that anterograde memory was also preserved, while a postoperative test of spatial learning in the Morris water maze confirmed that the hippocampal lesions impaired spatial learning. Together, these experiments refute the contention that the hippocampus is requisite for (non-spatial) olfactory memory consolidation, storage, or access, despite the condition that the information be rapidly acquired.  相似文献   
83.
OBJECTIVE: To assess whether women have a preference for Down syndrome screening test performance. METHODS: A structured questionnaire exploring women's preferences for screening test performance was administered to women attending their first prenatal visit who wished to have Down syndrome screening performed. RESULTS: One hundred and twenty women were interviewed. The majority of women (n=80) chose a screening test with a low screen-positive rate rather than the highest detection rate. The reasons given for this preference were a desire to minimise the risk of miscarriage of a normal baby and a belief that a detection rate of 80 to 90% was acceptable. However, older women (>37 years) chose a test with the highest detection rate possible, regardless of the higher screen-positive rate, preferring to miscarry a normal baby as a result of a diagnostic test rather than miss the detection of a baby with Down syndrome. Preferences were not influenced by previous screening experience. CONCLUSIONS: Women express different preferences for screening test performance. Maternal age rather than previous screening experiences appears to be the major influence in these choices.  相似文献   
84.
The fetal heart rate (FHR) variability is used as a parameter in evaluating fetal well-being. Persistent decreased or absent variability is considered a bad prognostic sign and usually prompts an emergency cesarean section.We present two cases of severely decreased FHR variability and emergency cesarean section in which the neonates were pronounced brain dead shortly after delivery.We believe that if intra-uterine brain death could be diagnosed on the basis of suspiciously persistent low or absent FHR variability, surgical procedures that endanger the health of the mother could be prevented. The possibility of intra-uterine brain death should be considered in all the cases of persistently low or absent FHR variability.  相似文献   
85.
86.
OBJECTIVE: To assess the viability of a strategy of primary resection with secondary liver transplantation (LT) for hepatocellular carcinoma (HCC) on cirrhosis. SUMMARY BACKGROUND DATA: LT is the optimal treatment of HCC with cirrhosis. Owing to organ shortage, liver resection is considered as a reasonable first-line treatment of patients with small HCC and good liver function, with secondary LT as a perspective in case of recurrence. The viability of such strategy, positively explored in theoretical models, is not documented in clinical practice. METHODS: Among 358 consecutive patients with HCC on cirrhosis treated by liver resection (n = 163; 98 of whom were transplantable) or transplantation (n = 195), the feasibility and outcome of secondary transplantation was evaluated in a 2-step fashion. First, secondary LT for tumor recurrence after resection (n = 17) was compared with primary LT (n = 195), to assess the risk and the outcome of secondary LT in patients who effectively succeeded to be treated by this approach. Second, primary resection in transplantable patients (n = 98) was compared with that of primary LT (n = 195) on an intention-to-treat basis, to assess the outcome of each treatment strategy and to determine the proportion of resected patients likely to be switched for secondary LT. Transplantability of resected patients was retrospectively determined according to selection criteria of LT for HCC. RESULTS: Operative mortality (< or =2 months) of secondary LT was significantly higher than that of primary LT (28.6% versus 2.1%; P = 0.0008) as was intraoperative bleeding (mean transfused blood units, 20.7 versus 10.5; P = 0.0001). Tumor recurrence occurred more frequently after secondary than after primary LT (54% versus 18%; P = 0.001). Posttransplant 5-year overall survival was 41% versus 61% (P = 0.03), and disease-free survival was 29% versus 58% (P = 0.003) for secondary and primary LT, respectively.Of 98 patients treated by resection while initially eligible for transplantation, only 20 (20%) were secondarily transplanted, 17 of whom (17%) for tumor recurrence and 3 (3%) for hepatic decompensation. Transplantability of tumoral recurrence was 25% (17 of 69 recurrences). Compared with primarily transplanted patients, transplantable resected patients had a decreased 5-year overall survival (50% versus 61%; P = 0.05) and disease-free survival (18% versus 58%; P < 0.0001), despite the use of secondary LT.On a multivariate analysis including 271 patients eligible for transplantation and treated by either liver resection or primary LT, liver resection alone (P < 0.0001; risk ratio [RR] = 3.27) or liver resection with secondary LT (P < 0.05; RR= 1.87) emerged as negative independent factors of disease-free survival as compared with primary LT. A number of nodules > 3 (P = 0.002; RR= 2.02) and a maximum tumor size exceeding 30 mm (P < 0.0001; RR=1.93) were also predictive of lower disease-free survival. CONCLUSIONS: LT after liver resection is associated with a higher operative mortality, an increased risk of recurrence, and a poorer outcome than primary LT. In addition, liver resection as a bridge to LT impairs the patient transplantability and the chance of long-term survival of cirrhotic patients with HCC. Primary LT should therefore remain the ideal choice of treatment of a cirrhotic patient with HCC, even when the tumor is resectable.  相似文献   
87.
We report a case of pulmonary lipoblastoma in a 2-year-old child. This pathology has not been previously reported in the English literature. Accepted: 3 July 2000  相似文献   
88.
 During the period 1994–1998, three patients with bilateral hydatid cysts of the lung (HCL) underwent operative removal of the cysts. In three of the six lungs operated upon the conventional technique was used: after removal of the cyst and suture closure of bronchial leaks, the chest was closed with an intercostal drainage tube. Two of these patients developed bronchopleural fistulae requiring rethoracotomy and prolonged hospital stays. The other three lungs were operated upon using the pneumonostomy technique: after excision of the cyst a separate catheter is fixed within the residual lung cavity and brought out through the adjacent chest wall, effectively marsupialising the residual cavity to the atmosphere. All these patients had an uneventful postoperative recovery. We conclude that the pneumonostomy technique is a very useful method of treating HCL surgically, especially when the cysts are bilateral and complicated. Accepted: 13 January 2000  相似文献   
89.
90.
Over an 8-yr period at the Houston Veterans Hospital, 731 endoscopic gastric salvage cytologies were performed in 671 patients, with surgical biopsy also done in 660. Seventy-six patients subsequently had tissue biopsy-proven or resection-proven malignancies. Salvage cytology had a sensitivity of 91% and a specificity of 100% for the detection of primary adenocarcinoma. Biopsy alone had a sensitivity of 92%; endoscopic gastric salvage cytology and surgical biopsy combined had a sensitivity of 100% in both primary and metastatic neoplasms. This study shows that the combination of endoscopic biopsy and salvage cytology increases the diagnostic accuracy for gastric carcinoma. Gastric salvage cytology requires minimal disruption of the routine endoscopic procedure and is therefore an easier and more rapid cytologic technique than gastric brushing cytology.  相似文献   
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