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101.
102.
Despite advances in multimodal therapy for neuroblastoma, survival from advanced disease remains poor. Children are now offered a wide variety of salvage regimens following relapse. A retrospective review was performed on 31 patients with recurrent neuroblastoma treated at one institution between 1995 and 2001. At initial diagnosis, 27 patients had metastatic disease and 11 had N-myc amplification (NMA). The median time to recurrence from diagnosis was 16.1 months. Seventeen patients received salvage therapy, with a median of three salvage regimens per patient. The median survival time from relapse was 8.4 months. The median survival time was significantly shorter for recurrence less than 6 months after stem cell transplantation (2.9 vs. 13.3 months; P = 0.003) and for patients with NMA (2.7 vs. 15.1 months; P < 0.0001). Overall, salvage therapy led to a significantly longer median survival time (22.4 vs. 3.3 months; P = 0.0003); however, salvage therapy extended the median survival time only from 2.2 to 3.2 months for patients with NMA and from 0.7 to 5.8 months for patients with early relapse after stem cell transplantation. Multiple salvage regimens prolong survival significantly, especially for patients with no NMA and for relapses more than 6 months after stem cell transplantation, but the long-term disease-free survival after recurrent disease remains dismal.  相似文献   
103.
PURPOSES: This study was designed to assess: a) whether rowing affects airway cell composition, and b) the possible relationship between the degree of ventilation during exercise and airway cells. SUBJECTS AND METHODS: In nine young, nonasthmatic competitive rowers (mean age +/- SD: 16.2 +/- 1.0 yr), induced sputum samples were obtained at rest and shortly after an all-out rowing test over 1000 m (mean duration: 200 +/- 14 s), during which ventilatory and metabolic variables were recorded breath-by-breath (Cosmed K4b, Italy). RESULTS: At rest, induced sputum showed prevalence of neutrophils (60%) over macrophages (40%); after exercise, total cell and bronchial epithelial cell (BEC) counts tended to increase. In the last minute of exercise, mean VE was 158.0 +/- 41.5 L x min(-1), and VO2 x kg(-1) 62 +/- 11 mL x min(-1). Exercise VE correlated directly with postexercise total cell (Spearman rho: 0.75, P < 0.05) an dmacrophage (rho: 0.82, P < 0.05) counts. A similar trend was observed for exercise VE and changes in BEC counts from baseline to postexercise (rho: 0.64, P = 0.11). Exercise VE did not correlate with airway neutrophil counts at rest or after exercise. Expression of adhesion molecules by airway neutrophils, macrophages, and eosinophils decreased after the all-out test. CONCLUSION: Similar to endurance athletes, nonasthmatic competitive rowers showed increased neutrophils in induced sputum compared with values found in sedentary subjects. The trend toward increased BEC postexercise possibly reflected the effects of high airflows on airway epithelium. Airway macrophages postexercise were highest in rowers showing tile most intense exercise hyperpnea, suggesting early involvement of these cells during exercise. However, the low expression of adhesion molecules by all airway cell types suggests that intense short-lived exercise may be associated with a blunted response of airway cells in nonasthmatic well-trained rowers.  相似文献   
104.
Classifying research proposals by risk of harm is fundamental to the approval process and the most pivotal risk category in most regulations is that of "minimal risk." If studies have no more than a minimal risk, for example, a nearly worldwide consensus exists that review boards may sometimes: (1) expedite review, (2) waive or modify some or all elements of informed consent, or (3) enroll vulnerable subjects including healthy children, incapacitated persons and prisoners even if studies do not hold out direct benefits to them. The moral and social purposes behind this threshold are discussed along with relevant views from the National Commission, NBAC, NHRPAC, Grimes v. Kennedy Krieger Institute, The Nuremberg Code, and The WMA's Declaration of Helsinki. Representative policies from Australia, Canada, South Africa, the U.S., and CIOMS are reviewed revealing different understandings of this sorting threshold. Six of nine frequently cited interpretations of "minimal risk" are untenable. The "absolute" interpretation of the "routine examination" standard is defended as best.  相似文献   
105.
There is little information on the lead levels of Indian children nationally. In the late 1990s, members of the Chippewa and Cree tribes living on the Rocky Boy Reservation near Box Elder, Montana, were concerned about environmental pollution and how it might be affecting the health of their children. With financial assistance from the Environmental Protection Agency, the tribes designed and implemented an innovative lead screening program for young children. Because most children on the reservation participated in WIC and Head Start, those programs were used to identify and screen close to 100% of young children on the reservation. The average blood lead level for children ages 1-5 on the Rocky Boy reservation was 2.4 micrograms/dL, which is not significantly different from that of children of the same age nationally. The project showed that Indian families will participate readily in screening programs that may improve their children's health.  相似文献   
106.
ABSTRACT:  Infants and children have special issues with regard to genital disease. Infants are incontinent, and have an increase in local irritation and infection risk. In addition, the adult sex hormones which enhance the health of genital skin are deficient. Also, the choice of therapy must be modified to take into account the more fragile nature of prepubertal skin, the tolerance of children to painful treatments, and the lack of experience of some medications in children.  相似文献   
107.
OBJECTIVE: Patterns of pubertal maturation may have an impact on several risk factors associated with adult morbidity and mortality, such as obesity. We examined the relationship of the initial manifestation of puberty in girls with anthropometric measures, as well as age at menarche. METHODS: White females (n = 1166, ages 9 and 10 at intake) were followed with annual visits for 10 years. Physical examinations included height, weight, skinfold thicknesses, and pubertal maturation assessment. RESULTS: During the course of the study, 443 of 859 eligible females (51.6%) were observed to have asynchronous maturation in the development of puberty, that is, initial areolar/breast (thelarche pathway) or pubic hair (adrenarche pathway) development, without development of the other characteristic. Using a longitudinal regression model, significant interactions were noted between initial pubertal manifestation and years since onset of puberty on the following outcomes: sum of skinfolds thickness, percent body fat, waist-to-hip ratio, and body mass index (BMI). However, age of onset of pubertal maturation was the same in the 2 groups (10.7 years). Females in the thelarche pathway had earlier menarche (12.6 vs 13.1 years) as well as greater skinfolds, body fat, and BMI at the time of menarche. Females in the thelarche pathway also had greater body fat and BMI 1 year before puberty and throughout puberty compared with those in the adrenarche pathway. CONCLUSIONS: Females who enter puberty through the thelarche pathway, as compared with the adrenarche pathway, had greater sum of skinfold thicknesses, BMI, and percent body fat 1 year before the onset, as well as throughout, puberty. Because larger body composition and earlier age of menarche of females in the thelarche pathway parallel the epidemiologic profiles of women who are obese or at risk for obesity, these females may be at greater risk for adult obesity.  相似文献   
108.
During pregnancy a localised human papillomavirus (HPV) lesion may, in rare cases, develop into a Büschke-Lowenstein tumour. The choice of treatment is crucial as standard systemic treatment is teratogenic. We performed laser CO2 microsurgery because it has a low incidence of complications.  相似文献   
109.
110.
BACKGROUND: EUS is highly accurate for staging gastric lymphoma. Because stage correlates to outcome, interobserver agreement is mandatory. However, previous studies suggest that interobserver agreement might vary according to T-stage. A multicenter evaluation of observer agreement with respect to endosonographic staging of gastric mucosa-associated lymphoid tissue (MALT) lymphoma was therefore conducted. METHODS: Fifty-four patients were studied; 42 were also evaluated after eradication of Helicobacter pylori infection. EUS was performed at different institutions by 10 experienced endosonographers who collected the best photographs for each examination. Interobserver agreement was estimated with kappa statistics. RESULTS: Overall interobserver agreement for T-stage was fair, both before and after treatment (kappa = 0.38 and kappa = 0.37, respectively). Overall interobserver agreement for N-stage was substantial before treatment, but only fair after treatment (kappa = 0.63 and kappa = 0.34, respectively). The lowest values of agreement occurred with T1sm (submucosa) and T2 stage lesions. CONCLUSIONS: Interobserver agreement for staging of gastric MALT lymphoma by EUS is suboptimal before as well as after treatment of H pylori infection. This evidence suggests that gastric EUS may be more difficult technically compared with EUS of other organs. Lack of agreement is crucial because it influences the choice of therapy and assessment of response to treatment. Good interobserver agreement would permit better communication concerning the clinical status of patients, comparison of the results of different studies, and stratification of patients within clinical trials.  相似文献   
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