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101.
This report describes a relapse of Salmonella paratyphi B infection in a child with biliary atresia, following 2 weeks of treatment with ciprofloxacin. The recrudescence was complicated by the development of osteomyelitis and was treated with chloramphenicol, trimethoprim, ceftriaxone and ampicillin in succession.  相似文献   
102.
动情间期母羊切除卵巢并皮下植入持续释放的E_2后,平均LH基础分泌水平和LH脉冲幅高比对照组显著减低,LH脉冲频率无明显改变。LH的平均基础分泌水平和脉?中幅高显著相关。表明植入E_2对垂体LH分泌的抑制作用主要是抑制LH对GnRH的反应,作用部位在垂体,不在下丘脑。LH基础分泌水平的下降,亦可能是E_2的抑制作用所致。  相似文献   
103.
Melanocyte stimulating hormone (MSH) plays an important role in determining the cutaneous response to ultraviolet radiation and may also influence melanoma progression. We have previously shown that variants of the melanocortin receptor present on melanocytes, MC1R, are associated with sun sensitivity and red hair in a UK population and therefore now consider the gene as a candidate for melanoma susceptibility. We have compared the frequency of known MC1R variants in the second and seventh transmembrane domains in 43 melanoma cases and 44 controls. MC1R variants were more common in cases than controls (chi 2 = 6.75, 1 d.f.; P = 0.0094) with a relative risk to carriers of variant alleles compared with normal homozygotes of 3.91 (95% c.l.: 1.48-10.35), and a population risk attributable to carriers of 34.6% (95% c.i. 10.7-52.1%). The Asp84Glu variant was only present in melanoma cases and appears to be of particular significance. The contribution of variant MC1R alleles was largely independent of skin type. Variants of the MC1R gene are likely to be causally associated with the development of melanoma.   相似文献   
104.
Structural equation modelling has already been used to study the relationship between feeding difficulty and nursing intervention in elderly people with dementia. Four models were tested and one provided an acceptable fit to the data. However, there were limitations in terms of sample size and the scales used to measure the variables related to feeding difficulty and nursing intervention. In the present study the sample size has been increased and the scaling of variables has been improved and an additional model has been tested. The best fitting model introduces a latent state variable to explain the relationship between feeding difficulty and nursing intervention. In order to study this relationship further several lines of investigation are suggested, including trait validation and state experimentation. These will be explained in the paper.  相似文献   
105.
Although there have been great advances in cancer diagnosis in recent years, it remains difficult to transfer tumor location information from cross-sectional computed tomographic (CT) scans or magnetic resonance images to the simulation and verification films used in planning radiotherapy. A newly developed system uses radioopaque markers attached to the patient as reference points. These markers are identified on both CT scans and simulation films and their locations entered into the treatment planning computer. The tumor and any desired normal structures are then outlined manually on each CT section. Transparent overlays produced by the computer show the position of the reference markers and tumor outlines for any combination of gantry angles and source-film distance. Because the overlays are scaled to the simulation films, the reference points enable precise alignment of overlay and film. The tumor outline thus appears on the simulation or verification films exactly as it is "seen" by the therapy beam, making field verification straightforward and accurate, even on oblique films.  相似文献   
106.
107.
Twenty one children with cystic fibrosis were advised to decrease their pancreatic enzyme supplement (PES) dose to less than 10,000 units lipase/kg/day. Mean PES dosage was significantly decreased in 15 patients from 18,380 to 8647 units lipase/kg/day. There were no significant changes in energy or fat intake, but there were significant increases in weight SD score, height SD score, and weight/height ratio.  相似文献   
108.
Excess cortisol levels are linked with brain atrophy and cognitive decline in older people. 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) potently amplifies intracellular glucocorticoid action by converting inert cortisone to active cortisol, but any causal importance in brain aging is unexplored. We tested the hypotheses that higher systemic 11β-HSD1 activity predicts brain atrophy and cognitive decline in older men. In a longitudinal study of 41 men (65-70 years old at baseline) we measured baseline systemic 11β-HSD1 activity, the urinary 5alpha- and 5beta-tetrahydrocortisol to tetrahydrocortisone ratio (ratio of tetrahydrometabolites of cortisol (THFs)/ratio of tetrahydrometabolites of cortisol (THE)), and assessed change in brain atrophy, white matter lesions and cognitive function over 6 years. Baseline THFs/THE correlated negatively with baseline hippocampal volumes (left: r = -0.37; right: r = -0.34; p < 0.05) and positively with ventricular volumes (r = 0.43, p = 0.006) and periventricular white matter lesions (rho = 0.31, p = 0.047). Importantly, baseline THFs/THE but not cortisol predicted increase in ventricular volumes (r = 0.33, p = 0.037) and decline in processing speed (r = -0.55, p = 0.0002) over 6 years. The predictive link between systemic 11β-HSD1 activity and progressive brain atrophy and cognitive decline suggests 11β-HSD1 inhibition as a plausible therapy for brain aging.  相似文献   
109.
110.

Background  

Childhood intelligence predicts mortality throughout most of the life span. However, it is unknown whether its effect persists into advanced old age.  相似文献   
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