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Background: Research has demonstrated that problem behavior has been associated with substance use, but knowledge is lacking on such associations in a low-income country like Nepal. Aims: This study aimed to find associations between emotional and behavioral problems and substance use among Nepalese adolescents. Method: A cross-sectional study was conducted at the end of 2011, with participants from three schools in the Province 4 of Nepal. We selected 408 adolescents aged 12 to 18 (mean 15.2 years, 54% boys) at one urban and two rural schools. The data were collected using the Youth Self-Report and Adolescents’ Substance Use Measurement. Results: Higher scores on withdrawn/depressed symptoms, thought problems, attention problems, delinquent or aggressive behavior or internalizing or externalizing problems were associated with the use of tobacco, alcohol or other substances. In the broadband scales, only internalizing problems predicted the use of intoxicants. Higher scores for attention problems predicted the use of tobacco, any intoxicants, and high-risk user. Conclusion: Our findings indicated that problem behavior among Nepalese adolescents was associated with substance use. Future studies should explore the association between problem behavior and substance use, including causal factors, so that risky behavior among Nepalese adolescents can be prevented.  相似文献   
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BACKGROUND: Nitric oxide (NO) plays a key role in wound repair and S-nitrosothiols like S-nitrosoglutathione (GSNO) are well known NO donors. METHODS: Animals were separated in two groups and submitted to excisional wounds on the dorsal surface at the first day. GSNO (100 microm)-containing hydrogels were topically applied on the wound bed in the GSNO group, daily, during the first 4 days. Control group was topically treated with hydrogel without GSNO for the same period. Wound contraction and re-epithelialization were measured. Animals were sacrificed 21 days after wounding. Samples of lesion and normal tissue were formalin-fixed, paraffin embedded for histological analysis. RESULTS: Wound contraction, measured 14 and 21 days after wounding, was greater in the GSNO group than in the control group (P<0.05 for both). The re-epithelialized wound area, measured 14 days after wounding, was higher in the GSNO group than in the control group (P<0.05). A higher amount of inflammatory cells was observed in superficial and deep areas of the granulation tissue of the control group compared to the GSNO group. Twenty-one days after wounding, thin red-yellow collagen fibers arranged perpendicularly to the surface were found in the granulation tissue of the control group, whereas in the GSNO-treated group collagen fibers were thicker and arranged parallel to the surface. Increased number of mast cells was observed in the GSNO group compared with that in the control group. Vascularization and myofibroblast distribution were similar in both groups. CONCLUSION: Topical application of GSNO-containing hydrogel during the early phases of rat cutaneous wound repair accelerates wound closure and re-epithelialization and affects granulation tissue organization.  相似文献   
3.
A new COMT inhibitor, nitecapone (OR-462) or clorgyline, a MAO-A inhibitor, was infused into the 3rd brain ventricle (i.c.v.) of conscious male rats. None of the enzyme inhibitors given alone alter hypothalamic or striatal levels of L-dopa, dopamine or their metabolites. Most of the rats were pretreated with levodopa/carbidopa (LD/CD, 15/30 mg kg-1 intraperitoneally). Now, the action of nitecapone is localized in the hypothalamus since homovanillic acid (HVA) is decreased there, not in the striatum. The levels of 3-O-methyldopa (3-OMD) are not changed in either brain region, suggesting a lack of the peripheral leakage of nitecapone. Clorgyline (3 and 10 micrograms rat-1) elevates hypothalamic and dopamine levels. Nitecapone and clorgyline decrease prolactin (PRL) levels below those reduced by LD/CD treatment.  相似文献   
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Haplotypic association of DDAH1 with susceptibility to pre-eclampsia   总被引:3,自引:0,他引:3  
Association between pre-eclampsia (PEE1) and the dimethylarginine dimethylaminohydrolase (DDAH) 1 and 2 genes, which play a role in the regulation of nitric oxide synthesis and release, was studied. In a case-control study design single nucleotide polymorphisms (SNPs) were determined at eight sites in the DDAH1 gene and at one site (Pro231Pro) in the DDAH2 gene from 132 women with pre-eclampsia and 112 healthy controls. Three SNPs in the DDAH1 gene were associated with pre-eclampsia, showing complete linkage disequilibrium with each other, but none of the associations in the allele or genotype data reached statistical significance in either of the genes after the correction for multiple testing. Haplotype frequencies were estimated using a population based on a maximum likelihood method (EM algorithm). Four common DDAH1 haplotypes were present and a significant association of haplotypes H2 and H3 with pre-eclampsia (P=0.03) was found. The risk of pre-eclampsia was greatest in individuals (odds ratio: 3.93; 95% confidence interval: 1.54-9.99) who had two copies of the high-risk haplotypes (H2 or H3). The observed haplotypic association provides the first evidence of the importance of DDAH1 polymorphisms in pre-eclampsia susceptibility.  相似文献   
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The effects of lesion of the hypothalamic paraventricular nuclei (PVNx), the main thyrotrophic area, on the cold-stimulated thyrotropin (TSH) responses to intracerebroventricular (i.c.v.) 5-HT were studied in male rats. PVNx significantly attentuated the cold-stimulated TSH levels, but significantly affected neither hypothalamic thyrotropin-releasing hormone nor somatostatin content. Serum T3 levels were significantly decreased 8 days after PVNx. Irrespective of the lesion (sham or PVNx), 5-HT infusion (9 micrograms per rat) into the posterior third ventricle attenuated markedly the cold-stimulated TSH levels, whereas infusion into the anterior third ventricle did not. Bilateral 5-HT infusions (2 micrograms per side) into the hypothalamic dorsomedial nuclei significantly decreased serum TSH, but bilateral infusions into the posterior hypothalamic nuclei were without effect. Sham-lesion and PVNx decreased serum prolactin levels without affecting the stimulation of prolactin secretion by i.c.v. 5-HT. These results suggest that the inhibitory effect of i.c.v. 5-HT on TSH secretion and its stimulatory action on prolactin secretion are only partially dependent on the PVN.  相似文献   
8.
目的 在儿童骨延长的患儿中 ,为了能够有效地控制骨延长的速率 ,达到骨延长的目的 ,采用双能量X线骨质密度测量仪 (dualenergyX Rayabsorptiometry ,DEXA)监测延长断端骨矿含量 (bonemineralcontent,BMC)的变化。方法  30例患儿中有 5 0处下肢作了骨延长术 ,平均年龄10 .9岁 (5~ 17岁 ) ,引起短肢的病因不同。术后 7~ 10d开始行骨延长 ,每次延长 0 .2 5mm ,每天 4次。牵引延长期间每周扫描一次 ,拆除外固定器后每 2周扫描一次到术后 2年。DEXA扫描的分辨率是 1mm× 1mm ,扫描速度 30mm/s。比较不同延长时期中骨矿含量的变化。分析不同病因和不同外固定器之间骨矿含量变化的差别。结果 不同固定器之间骨矿含量的差别无著性意义。根据骨延长区BMC增加速率 ,将患儿分为快速组、一般组和慢速组。快速组每日BMC增加速率为 0 .3%~ 0 .6 % ,新骨生长快速 ;一般组每日BMC增加 0 .1%~ 0 .3% ,新骨中速生长 ;慢速组每日增加 <0 .1% ,新骨生成缓慢。骨矿化速率与原发病因相关。结论 DEXA能动态监测骨延长中新生骨的骨矿含量的变化 ,根据骨矿含量变化的程度 ,能够调整骨延长的速率 ,从而达到预期骨延长的目的。  相似文献   
9.
BACKGROUND: Boys and young men with hemophilia treated with factor infusions before 1985 had a substantial risk of acquiring the human immunodeficiency virus (HIV) and the acquired immunodeficiency syndrome. This study was designed to assess the effects of HIV and hemophilia per se on neurological function in a large cohort of subjects with hemophilia, and to investigate the relationships between neurological disease and death during follow-up. METHODS: Three hundred thirty-three boys and young men (207 HIV seropositive and 126 HIV seronegative) were evaluated longitudinally in a multicenter, multidisciplinary study. Neurological history and examination were conducted at baseline and annually for 4 years. The relationship between neurological variables, HIV serostatus, CD4+ cell counts, and vital status at the conclusion of the study was examined using logistic regression models. RESULTS: The risks of nonhemophilia-associated muscle atrophy, behavior change, and gait disturbance increased with time in immune compromised HIV-seropositive subjects compared with HIV seronegative or immunologically stable HIV-seropositive subjects. The risk of behavior change in immune compromised HIV-seropositive hemophiliacs, for example, rose to 60% by year 4 versus 10% to 17% for the other study groups. Forty-five subjects (13.5%), all of whom were HIV seropositive, died by year 4. Subjects who died had had increased risks of hyperreflexia, nonhemophilia-associated muscle atrophy, and behavior change. CONCLUSIONS: These results indicate that immune compromised, HIV-seropositive hemophiliacs have high rates of neurological abnormalities over time and that neurological abnormalities were common among subjects who later died. By contrast, immunologically stable HIV-seropositive subjects did not differ from the HIV-seronegative participants. Hemophilia per se was associated with progressive abnormalities of gait, coordination, and motor function.  相似文献   
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