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OBJECTIVE: Children with hydrocephalus are characterised by slow linear growth in prepuberty, accelerated physical maturation during puberty, and reduced final height. We aimed to study the possible roles of growth hormone, insulin-like growth factor-I (IGF-I), and IGF binding protein-3 (IGFBP-3) in this growth pattern. STUDY DESIGN: One hundred and fourteen patients with shunted hydrocephalus (62 males) aged 5 to 20 years, of whom 17 had spina bifida (six males), and 73 healthy controls (38 males) were studied. Anthropometric measures, body mass index, and body fat mass were assessed and the stage of puberty was determined. Serum growth hormone and plasma IGF-I and IGFBP-3 concentrations were measured. RESULTS: The patients comprised 44 (26 males) who were prepubertal and 70 (36 males) pubertal or postpubertal, while 32 of the controls (19 males) were prepubertal and 41 (19 males) pubertal or postpubertal. The prepubertal children with hydrocephalus had lower IGF-I (p = 0.002) and IGFBP-3 concentrations (p < 0.001) than the controls, and the pubertal children had four times lower basal growth hormone concentrations (p < 0.001). There was a correlation between height SD score and IGF-I levels in the total patient population (r = 0.23; p = 0.01). Peripheral IGF-I concentrations peaked at pubertal stages 2-3 in the female patients and at stage 4 in the controls. The prepubertal patients on antiepileptic treatment, carbamazepine in most cases (73%), had higher IGF-I (p = 0.01) and IGFBP-3 concentrations (p = 0.03) than those who had never been treated with antiepileptic drugs, but still lower IGFBP-3 levels than the controls (p = 0.01). CONCLUSION: Based on these findings, it can be concluded that reduced growth hormone secretion may contribute to the pattern of slow linear growth and reduced final height observed in these patients.  相似文献   
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OBJECTIVE: Although breastfeeding is associated with lower rates of a variety of infant illnesses, skeptics have suggested that much of the association is attributable to confounding, even after appropriate statistical adjustment. This article utilizes a novel design to investigate changes in infant illness at the community level after a successful breastfeeding promotion program. METHODS: In this population-based cohort study, the medical records of all infants born in one Navajo community the year before a breastfeeding promotion program (n = 977) and the year during the intervention (n = 858) were reviewed. Outcomes assessed include changes after the intervention in: proportion breastfeeding and/or breastfeeding exclusively; incidence of common infant illnesses in the first year of life; and feeding-group specific incidence of illness. RESULTS: The proportion of women breastfeeding exclusively for any period of time increased from 16.4% to 54.6% after the intervention. The percent of children having pneumonia and gastroenteritis declined 32. 2% and 14.6%, respectively, after the intervention. Feeding-group specific rates of these illnesses were unchanged, indicating that the decline observed was attributable to the increased proportion of infants breastfeeding. In contrast, rates of croup and bronchiolitis increased after the intervention among those fed formula from birth, suggesting a viral epidemic which was limited to those never exclusively breastfed. Finally, sepsis declined in both formula-fed and breastfed infants after the intervention, suggesting that other factors affected this illness outcome after the intervention. CONCLUSIONS: Increasing the proportion of exclusively breastfed infants seems to be an effective means of reducing infant illness at the community level. The experimental design suggests that the increased incidence of illness among minimally breastfed infants is causally related to lack of breast milk, rather than being attributable to confounding.  相似文献   
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PCR-SSCP快速检测耐多药结核分枝杆菌   总被引:1,自引:0,他引:1  
目的:了解本地区结核病耐药基因突变情况,探讨PCR-SSCP作为新的分子药敏试验方法在临床的应用价值。方法:通过提取耐INH、RFP、SM的肺结核患者痰中结核分枝杆菌DNA,进行PCR-SSCP分析,检测结核分枝杆菌rpoB、katG、rpsL基因是否存在突变,并与传统L-J药敏实验对照。结果:30株耐多药株中,耐RPF、INH、SM基因突变阳性率为90%(27/30)、63%(19/30)、53%(16/30)。3个基因联合突变共8株(26.7%),2个基因联合突变共18株(60%),即26株(86.7%)。单基因突变共2株,2株无基因突变。结论:通过PCR-SSCP方法可检测出绝大部分耐多药结核病的耐药基因,rpoB、katG、rpsL基因突变与本地区结核杆菌对RFP、INH、SM耐药性有关。与传统L-J药敏实验对比,PCR-SSCP是一种敏感、快速的指导临床用药的先进检测方法。  相似文献   
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Female circumcision is a traditional practice common in African countries. It involves partial or total removal of external female genitalia. It has led to many complications, in particular, the scarring of the external genitalia. The consequence is a very narrow introitus making the intracavitary brachytherapy treatment component difficult when these women develop cancer of cervix. We present two such cases from our institution. Our aim is to make the radiation and gynecological oncologists, both in developed and developing countries, aware of this practice and the problems they can encounter in the management of such cases. Intracavitary brachytherapy is an important component in the potentially curative role of radiation therapy for cervical cancer. Every effort should be made to ensure that the sequelae of genital mutilation does not deprive these women of the same standard of care as the general population.  相似文献   
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OBJECTIVE: To evaluate the independent and combined effects of high-frequency oscillatory ventilation (HFOV) and partial liquid ventilation (PLV) on gas exchange, pulmonary histopathology, inflammation, and oxidative tissue damage in an animal model of acute lung injury. DESIGN: Prospective, randomized animal study. SETTING: Research laboratory of a health sciences university. SUBJECTS: Fifty New Zealand White rabbits. INTERVENTIONS: Juvenile rabbits injured by lipopolysaccharide infusion and saline lung lavage were assigned to conventional ventilation (CMV), PLV, HFOV, or high-frequency partial liquid ventilation (HF-PLV) with a full or half dose (HF-PLV1/2) of perfluorochemical (PFC). Uninjured ventilated animals served as controls. Arterial blood gases were obtained every 30 mins during the 4-hr study. Histopathologic evaluation was performed using a lung injury scoring system. Oxidative lung injury was assessed by measuring malondialdehyde and 4-hydroxynonenal in lung homogenates. MEASUREMENTS AND MAIN RESULTS: HFOV, PLV, or a combination of both methods (HF-PLV) resulted in significantly improved oxygenation, more favorable lung histopathology, reduced neutrophil infiltration, and attenuated oxidative damage compared with CMV. HF-PLV with a full PFC dose did not provide any additional benefit compared with HFOV alone. HF-PLV1/2 was associated with decreased pulmonary leukostasis compared with HF-PLV. CONCLUSIONS: The combination of HFOV and PLV (HF-PLV) does not provide any additional benefit compared with HFOV or PLV alone in a combined model of lung injury when lung recruitment and volume optimization can be achieved. The use of a lower PFC dose (HF-PLV1/2) is associated with decreased pulmonary leukostasis compared with HF-PLV and deserves further study.  相似文献   
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Ethnopharmacological relevance

Petiveria alliacea L. (tipi) a shrub from Phytolaccaceae family is popularly used in folk medicine for treating a wide variety of disorders in South and Central America.

Aim of the study

To investigate the neuropharmacological properties on experimental animals.

Materials and methods

The acetate (FA), hexanic (FH), hydroalcoholic (FHA) and precipitated hydroalcoholic (FHAppt) fractions from the root of tipi were studied to investigate its pharmacological properties in the classical behavioral models (open-field, elevated plus maze-EPM, rotarod, barbiturate-induced sleeping time, forced swimming and pentylenetetrazole (PTZ)-induced convulsions tests) using mice. These fractions were administered intraperitoneally and orally to female mice at single doses of 100 and 200 mg/kg.

Results

All these fractions decreased the locomotor activity, rearing and grooming in the open-field test, suggesting a possible central depressant action. No significant effect was evident on motor coordination of the animals in the rotarod test. On EPM, all the fractions of tipi presented a significant reduction on the time of permanence in the open arms, indicating an absence of anxiolytic-like effect. In addition, the fractions increased the immobility time in the forced swimming test and potentiated pentobarbital-induced sleeping time in mice, confirmed a probable sedative and central depressant effect. Furthermore, the fractions increased the latency to the first convulsion and the lethal time of the PTZ-induced convulsions test in the animals, confirmed its popular use as anticonvulsant.

Conclusion

Our results suggest that the fractions of P. alliacea L. contains biologically active substance(s) that might be acting in the CNS and have significant depressant and anticonvulsant potentials, supporting folk medicine use of this plant.  相似文献   
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