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221.
Bicycling in Sweden has almost doubled between 1980 and 1992/3 among persons aged 25-64 y. The upward trend is continuing. For the elderly (65 or older) the bicycle is a common means of transport, in both Sweden and a number of other countries. Almost one-third of the Swedish population aged 65 or older bike at some time during the year. The objectives of this study are to describe the pattern of, and trend in, bicycle-related injuries among the elderly in Sweden and to discuss possible means of injury prevention. Mortality data come from official death certificates (1967-96). Hospital-discharge data (1985-96) are also employed, divided into three age groups (-14, 15-64 and 65-), by external cause according to the ICD-9, and also into 'all diagnoses' and 'head injuries'. Number of cases and days of hospital care for persons aged 65 or more, on aggregate and by gender, are reported for 1996. The whole of Sweden and its northern and southern parts separately were investigated. 2830 bicyclists were killed over the period 1967-96, of which 47% were 65 or older. The risk of dying due to bicycling was about 3.7 times greater among the elderly than among children aged 14 or under. There were significant changes in injury trends for all age groups between 1985 and 1996 with regard to hospital care. Annual average decreases for children, of 2.2% for all diagnoses and of 3.4% for head injuries, were observed. For the other two age groups there were increases in all injuries of 3.4% (15-64) and of 2.9% (65-), and increases in head injuries of 4.6% (15-64) and 2.7% (65-). For the elderly living in the southern part of Sweden, there was an increase on average of 2.2% per year over the period, compared with 4.2% for those in the northern part. Males showed a higher incidence of injuries and received longer periods of care than females. Do we have an epidemic of bicycle injuries among the elderly? They face a greater risk of being injured or killed than his/her younger counterpart. For all ages the risk is 7.4 times higher for a bicyclist than for a car driver. The risk for the elderly is about 3 times greater than for the average bicyclist, and as much as 6 times higher for the age group 75-84 y. With some few exceptions, there is no doubt that society has neglected the problem. Decision-makers have a tendency to focus on the relatively young. But people are living longer today and the elderly are healthier, which indicates the need for greater interest and more intervention. We have signs of an epidemic, but one that can be ameliorated or prevented. Just waiting for injury to occur leads only to premature death or lifelong disability.  相似文献   
222.
Under the supervision of the central and local health authorities, a pilot project was conducted in four villages in the Luangprabang Province, Lao PDR. The objective of the project was to test different regimes to supplement females with oral iron preparations to reduce iron deficient anemia (IDA) and control iodine deficiency disorders (IDD) in school children. Compared with iron sulphate tablets, iron fumerate tablets were well accepted and good compliance results were achieved. Hemoglobin concentration improved only in the group of females taking iron fumerate tablets. The goiter rate decreased from approximately 90% to about 45% for school children, regardless of whether iodine salt were used by their families or whether iodine capsules were used to treat the children. The latter attempt was hampered by the fact that also in the control village iodine fortified salt was used. This was due to a governmental attempt to control IDD nation-wide. Therefore, also in the control village a significant decrease in the goiter rate was observed.  相似文献   
223.
The weight, height, body mass index (BMI), waist/hip ratio, serum leptin and lipid profiles of 48 overweight (BMI > or = 25.00). Thai males and 166 overweight Thai females, compared with 26 males and 81 females in a control group (BMI = 18.5-24.9 kg/m2), were investigated. Subjects for the study were those persons who turned up regularly for physical check-ups at the out-patient department, general practice section of the Rajvithi Hospital, Bangkok. The study was conducted between March-October, 1998. Statistically significantly higher levels of serum leptin, cholesterol, LDL-C, LDL-C/HDL-C ratio and triglyceride were found in the overweight compared with the control subjects. The median serum leptin concentration in overweight subjects was 19.6 (2.0-60.0 ng/ml) compared with 9.0 (range 1.0-30.0 ng/ml) in the control subjects (p < 0.001). The median values of leptin serum concentrations in the overweight and obese males were significantly higher than those of the overweight and obese females. A total of 66.7% (32 out of 48) of the overweight and obese males had elevated leptin levels, while elevated leptin levels were found in 87.3% (145 out of 166) of the overweight and obese females. A total of 18.8% and 21.1% of the overweight and obese males and females respectively had cholesterol concentrations of > or = 6.48 mmol/l. However, the prevalence of low HDL-C (HDL-C < or = 0.91 mmol/l) was found to be 41.7% in the overweight and obese males and 4.2% in the overweight and obese females. Statistically significant associations were found between weight, height, BMI, waist, hip, waist/hip ratio, HDL-C, and serum leptin in both overweight male and female subjects. A negative correlation was found between serum leptin and LDL-C/HDL-C ratio in both the overweight and obese subjects.  相似文献   
224.
  • 1 Endothelial cells have a key role in the cardiovascular system. Most endothelial cell functions depend on changes in cytosolic Ca2+ concentrations ([Ca2+]i) to some extent and Ca2+ signalling acts to link external stimuli with the synthesis and release of regulatory factors in endothelial cells. The [Ca2+]i is maintained by a well‐balanced Ca2+ flux across the endoplasmic reticulum and plasma membrane.
  • 2 Cyclic nucleotides, such as cAMP and cGMP, are very important second messengers. The cyclic nucleotides can affect [Ca2+]i directly or indirectly (via the actions of protein kinase (PK) A or PKG‐mediated phosphorylation) by regulating Ca2+ mobilization and Ca2+ influx. Fine‐tuning of [Ca2+]i is also fundamental to protect endothelial cells against damaged caused by the excessive accumulation of Ca2+.
  • 3 Therapeutic agents that control cAMP and cGMP levels have been used to treat various cardiovascular diseases.
  • 4 The aim of the present review is to discuss: (i) the functions of endothelial cells; (ii) the importance of [Ca2+]i in endothelial cells; (iii) the impact of excessive [Ca2+]i in endothelial cells; and (iv) the balanced control of [Ca2+]i in endothelial cells via involvement of cyclic nucleotides (cAMP and cGMP) and their general effectors.
  相似文献   
225.
The N-hydroxylation of carcinogenic arylamines represents an initial step in their metabolic activation. Animal studies have shown that this reaction is catalyzed by the cytochrome P450 (P450) enzymes P450 1A1 and P450 1A2. In this study, utilizing enzymes expressed in Escherichia coli (and purified) or in human B-lymphoblastoid cells, the catalytic activities of recombinant human P450 1A1, P450 1A2, and P450 3A4 for N- hydroxylation of several carcinogenic arylamines were determined. P450 1A2 from both expression systems catalyzed the N-hydroxylation of 4- aminobiphenyl and the heterocyclic amines, 2-amino-3-methylimidazo[4,5- f/quinoline (IQ), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). Rates were similar, with values of 1.1-7.8 nmol/min/nmol P450. In contrast, P450 1A1 catalyzed N-hydroxylation of only PhIP, and no activity was observed with P450 3A4. Further kinetic analysis with purified P450 1A2 showed similar Km and Vmax values for N-hydroxylation of the arylamines. Furafylline and fluvoxamine, inhibitors of P450 1A2 activity in human liver microsomes, were found to be inhibitory of the recombinant P450 1A2 N-hydroxylation activity. Results from this study are supportive of a major role for human P450 1A2 in the metabolic activation of arylamines.   相似文献   
226.
227.

BACKGROUND AND PURPOSE

Lipoxin A4 (LXA4) is a lipid mediator involved in the resolution of inflammation. Increased levels of LXA4 in synovial fluid and enhanced expression of the formyl peptide receptor 2/lipoxin A4 receptor (FPR2/ALX) in the synovial tissues of rheumatoid arthritis patients have been reported. Endothelins (ETs) play a pivotal pro-inflammatory role in acute articular inflammatory responses. Here, we evaluated the anti-inflammatory role of LXA4, during the acute phase of zymosan-induced arthritis, focusing on the modulation of ET-1 expression and its effects.

EXPERIMENTAL APPROACH

The anti-inflammatory effects of LXA4, BML-111 (agonist of FPR2/ALX receptors) and acetylsalicylic acid (ASA) pre- and post-treatments were investigated in a murine model of zymosan-induced arthritis. Articular inflammation was assessed by examining knee joint oedema; neutrophil accumulation in synovial cavities; and levels of prepro-ET-1 mRNA, leukotriene (LT)B4, tumour necrosis factor (TNF)-α and the chemokine KC/CXCL1, after stimulation. The direct effect of LXA4 on ET-1-induced neutrophil activation and chemotaxis was evaluated by shape change and Boyden chamber assays respectively.

KEY RESULTS

LXA4, BML-111 and ASA administered as pre- or post-treatment inhibited oedema and neutrophil influx induced by zymosan stimulation. Zymosan-induced preproET-1 mRNA, KC/CXCL1, LTB4 and TNF-α levels were also decreased after LXA4 pretreatment. In vitro, ET-1-induced neutrophil chemotaxis was inhibited by LXA4 pretreatment. LXA4 treatment also inhibited ET-1-induced oedema formation and neutrophil influx into mouse knee joints.

CONCLUSION AND IMPLICATION

LXA4 exerted anti-inflammatory effects on articular inflammation through a mechanism that involved the inhibition of ET-1 expression and its effects.  相似文献   
228.
A comparative study on the nutritional status of primiparous and multiparous women in the first trimester of pregnancy was conducted in the northeastern province of Thailand, Khon Kaen, to investigate differences in protein-energy-malnutrition, iron deficiency anaemia, vitamin A deficiency and carotenoid status between both parity groups. 94 subjects were recruited at first attendance of antenatal clinic. Data about weight, height, haemoglobin and haematocrit were obtained from hospital records. Anthropometric measurements of mid-upper arm circumference and triceps skinfold were done on a sub sample. Retinol, carotenoids and alpha-tocopherol were analysed using a reversed-phase high-performance liquid chromatography method. Ferritin, transthyretin and retinol-binding protein were determined by enzyme-linked immunosorbent assay. Primiparous women showed lower body mass index, mid-upper arm circumference, corrected arm muscle area (P<0.001) as well as lower retinol, cholesterol and triceps skinfold (P<0.05). After adjusting for age and socio-economical status the significant difference persisted for all parameters but triceps skinfold. No significant differences of alpha-tocopherol, serum proteins, carotenoids and iron indices could be observed, even though a tendency to higher values for ferritin, haemoglobin and haematocrit was shown in multiparous women. Prevalence of protein-energy-malnutrition (body mass index <18.5 kg/m2) in the primiparous group was significantly higher compared to the multiparous group (P<0.05). Prevalence of protein-energy-malnutrition, iron deficiency anaemia and vitamin A deficiency were 15.1%,6.3% and 3.3%, respectively, in the total study population. No differences between parity groups could be observed for prevalence of iron deficiency anaemia and vitamin A deficiency.  相似文献   
229.
大花红景天化学成分的研究   总被引:14,自引:1,他引:14  
王曙  王锋鹏 《药学学报》1992,27(2):117-120
从大花红景天(Rhodiola crenulata)根中分离出六个成分(Ⅰ~Ⅳ)。应用与已知品对照理化常数和光谱数据,鉴定Ⅰ,Ⅱ,Ⅲ,Ⅳ和Ⅴ分别为红景天苷(salidroside Ⅰ)、酪醇(p-tyrosolⅡ)、焦棓酸、没食子酸和β-谷甾醇。Ⅵ(大花红天素crenulatin)为一新的△1-异戊烯-3-氧-β-D-葡萄糖苷(△1-isopentenyl-3-O-β-D-glucopyranoside),由光谱法证明其结构为Ⅵ。  相似文献   
230.
Around 3% of the individuals with painful ophthalmoplegia have bilateral complaints. In the vast majority of these cases, appropriate investigation demonstrates a secondary etiology, and we are not aware of idiopathic cases reported. Herein we report a case of bilateral ophthalmoplegia where extensive investigation did not suggest a secondary cause.  相似文献   
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