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41.
MV Kamath J Halton A Harvey S Turner-Gomes A McArthur RD Barr 《Canadian Metallurgical Quarterly》1998,12(3):635-640
Lower levels of baseline ventilatory function have consistently been associated with increased risk of cardiovascular mortality in prospective studies, but the underlying mechanisms are not known. Increased risk of coronary heart disease is associated with higher serum insulin levels. This report examines the relationship between ventilatory function and indirect measures of insulin resistance. Cross-sectional data from 922 nondiabetic participants in the Normative Aging Study were analysed using multiple linear regression models with adjustment for potential confounders. Forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) were examined in relation to indicators of insulin resistance, i.e. fasting insulin and the fasting insulin resistance index (FIRI). Diabetics were excluded because impaired insulin secretion interferes with the validity of these as measures of insulin resistance. Fasting insulin and FIRI were negatively correlated with FVC and FEV1 (all p< 0.001). These associations persisted after adjusting for potential confounders including age, height, body mass index, waist to hip circumference ratio, physical activity, alcohol intake and smoking in separate multiple linear regression models, for both insulin (all p< or =0.0008) and FIRI (all p< or =0.0001). Negative cross-sectional associations between ventilatory function and indirect measures of insulin resistance were found in nondiabetic males. Insulin resistance may contribute to the previously unexplained association between ventilatory function impairment and cardiovascular mortality. Mechanisms underlying the relationship between insulin resistance and decreased ventilatory function remain to be elucidated. 相似文献
42.
OBJECTIVES: Sensory nerves play an important role in mediating neurogenic inflammation and subsequent tissue healing. A decrease in sensory nerve function with increasing age has been reported to correlate with poor tissue healing. Sympathetic nerves are known to modulate sensory nerve function, and changes in this modulation could also have important implications with ageing. The aims of this study were to examine the effect of different frequency electrical stimulation (ES) on the microvascular responses obtained to sensory nerve activation in young, aged and capsaicin-pretreated rats and modulation of these responses by sympathetic efferents. METHODS: Using laser Doppler flowmetry, vascular responses to antidromic ES of the sciatic nerve were monitored in the base of vacuum-induced blisters in the hind footpad. The non-selective alpha-adrenoceptor antagonist phentolamine (3 mg/kg, i.v.) was administered 20 min prior to ES. RESULTS: At high frequency ES (20V, 2ms, 15Hz for 1 min), the vascular response in old rats was significantly reduced (46 percent decrease, p < 0.05) compared to young control. At low frequency ES (20 V, 2 ms, 5 Hz for 1 min) however, older rats produced similar vascular responses to the young. Capsaicin-pretreated rats showed significantly reduced vascular responses to both high and low frequency ES, regardless of age. Pretreatment with phentolamine significantly increased the microvascular response in young rats at high (87 percent) and low (36 percent) frequency ES. In contrast, phentolamine significantly increased the ES-induced response in old rats at high frequency only (147 percent increase). CONCLUSIONS: The results suggest that the aged sensory nerve responds preferentially to low frequency ES and that sympathetic efferents exert an inhibitory modulatory effect on the vascular response evoked by sensory nerve stimulation. There are age-related changes in sympathetic modulation of sensory nerve-mediated responses which is dependent on stimulation frequency. 相似文献
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44.
Genetic variation among malaria parasites has important consequences with regard to drug resistance, pathogenicity, immunity, transmission, and speciation. In this regard, malaria parasites have been shown to display a high degree of inter- and intra-species genetic divergence. The nuclear genomes of Plasmodium falciparum, Plasmodium yoelii, and Plasmodium gallinaceum are vastly divergent yet share a similar codon usage and total A/T content of approximately 82%. This is in contrast to other primate-specific species including P. vivax which have an A/T content of approximately 67%. To assess the effects of this evolutionary divergence on the conservation of gene content, organization, and codon usage in the mitochondrial DNA (mtDNA) of malaria parasites, we have cloned and sequenced the mitochondrial genome of Plasmodium vivax, and compared it with the mtDNAs of P. falciparum, P. yoelii, and P. gallinaceum. The P. vivax mitochondrial genome was found to be 5990 base pairs in length, and displayed a gene organization identical to that of P. falciparum, P. yoelii, and P. gallinaceum. Furthermore, there was a remarkable 90% conservation of sequence identity between the mitochondrial genomes of all four species. As an example of intra-species conservation, comparison of mtDNAs from two independently cloned P. falciparum isolates, Malay Camp and C10, revealed only a single nucleotide substitution. A/T content of the P. vivax mitochondrial genome was found to be identical to other species of Plasmodium, hence, we have postulated that the mitochondrial genomes of malaria parasites were refractory to the evolutionary shifts in nucleotide content seen among the nuclear genomes of malaria parasites. Among different Plasmodium species, the second position of mitochondrial codons were found to be the least prone to substitutions and displayed a significant bias in pyrimidines. These aspects of mitochondrial codon usage were distinct from the nuclear genome and may reflect functional aspects of decoding by the mitochondrial translational system. 相似文献
45.
This article discusses a longitudinal study of change in disruptive behaviors among nursing home residents treated with neuroleptics compared with those not treated with neuroleptics. Observations were made of 201 participants on admission to and after 1 year in eight skilled nursing facilities. Nine disruptive behaviors were measured using the Psychogeriatric Dependency Rating Scale with nursing assistants. Neuroleptic use was documented from medication records. Odds ratios are reported for the association of behavior at baseline and use of neuroleptics on nine problem behaviors. For those who received neuroleptics during the year, there was greater change in both developing and resolving disruptive behaviors than for those not receiving neuroleptics. For both groups, restless or pacing behavior and belligerent behavior manifested by refusing instructions changed the most, both in developing and in apparently resolving. Our results show that change in disruptive behaviors occurs among nursing home residents regardless of neuroleptic use, but it occurs more frequently among those who receive neuroleptic medication. Knowledge of which disruptive behaviors are most likely to resolve or develop is important in training nursing home staff to cope with the behaviors as well as in planning interventions that may modify such behaviors. 相似文献
46.
The authors report the coexistence of vascular nevi (hemangiomas and arteriovenous malformations (AVMs) of the skin) with AVMs and venous malformations of the brain in male siblings from two related but nonconsanguineous families of three generations. The proband, his siblings, parents, aunts, uncles, and cousins were examined, underwent magnetic resonance (MR) imaging and MR angiography, and when appropriate, cerebral angiography. A father had vascular nevi and a mother, his sister, had an azygos anterior cerebral artery. No other cutaneous or cerebrovascular malformations were present in the parents. Each of the two families had two boys and one girl, 9 to 18 years of age. All the children had vascular nevi and all of the boys had coexisting cerebrovascular malformations: AVMs in three, and a venous malformation in another. One boy had three cerebral AVMs. Two boys had a cerebral hemorrhage, and one also had focal motor seizures. The skin lesions were not those of the Sturge-Weber-Dimitri, Rendu-Osler-Weber, or Wybum-Mason syndromes. The association of cutaneous and cerebrovascular malformations was seen only in males in these families. but females have also been reported in the literature. The results obtained in these families and three other families reported from Western and Central Europe indicate that the association of cerebral and cutaneous vascular hamartomas constitutes a distinct, hereditary clinicopathological entity with autosomal dominant inheritance and variable penetrance. The clinical manifestations of this syndrome are visible, painful vascular nevi, epilepsy, cerebral hemorrhage, and focal neurological deficits. The preponderance of male patients with the full expression of the syndrome suggests a possible hormonal influence on the expression of the gene. 相似文献
47.
RD Jones AR Visram JP Kornberg MG Irwin WM Gunawardene 《Canadian Metallurgical Quarterly》1994,22(5):539-544
We studied 30 children, aged 4 to 12 years, undergoing elective circumcision, premedicated with midazolam 0.5 mg.kg-1 and atropine 0.02 mg.kg-1 by mouth. A modified postbox test and the coding component of the Wechsler intelligence scale (WISC-R) was used to assess the preoperative effect of premedication on psychomotor function. Mood and sedation were also scored and related to serum midazolam concentrations. The children showed a significant decline in psychomotor performance 30 and 60 minutes after premedication when compared with their best unmedicated performance recorded the previous evening. This decline in psychomotor performance was only weakly associated with serum midazolam concentrations (r = 0.1). The postbox toy ratio is a suitable measurement of psychomotor performance in children because of its simplicity and ease of use in the clinical environment, although it may suffer the "test-retest" limitations of similar types of assessment. The sedative and anxiolytic effects of midazolam provide a quiet environment for a smooth induction of anaesthesia. 相似文献
48.
R Casali G Girardi RD Mediati P Livi GP Novelli 《Canadian Metallurgical Quarterly》1995,61(12):501-507
BACKGROUND: The aim of the study is to determine what concentration of ketorolac and morphine administered together i.v. achieve best synergic effect between NSAID antiinflammatory and opioids analgesic properties. DESIGN: Randomized comparative study was carried out on 180 patients, ASA II-IV, undergoing major general surgery, in an University Clinic. METHODS: Postoperative pain therapy by i.v. PCA: group 1 morphine 0.75 mg.ml + ketorolac 0.75 mg.ml; group 2 morphine 0.50 mg.ml + ketorolac 1.50 mg.ml; group 3 morphine 0.25 mg.ml + ketorolac 1.50 mg.ml; in saline solution. Initial bolus: 2 ml. Continuous infusion 1.5 ml.h. Demand bolus: 0.2 ml. Lockout time: 30 minutes. Evaluations included: pain intensity (T0, T3, T18); total amount of infused drugs (T18); number of valid demands and attempts (T18); amount of autoadministered analgesic drugs in percent of highest available amount (T18); side effects (T18); patient's judgment. DATA ANALYSIS: ANOVA and Student's "t"-test. RESULTS: A statistically significant reduction of pain intensity was found after 3 and 18 hours in the three groups, no differences were found among the groups. Group 2 required an amount of autoadministered drugs significantly lower than other groups. Rare side effects. Patient's judgment was generally positive. CONCLUSIONS: Results suggest a greater synergetic effect between morphine and ketorolac in concentrations used in group 2. 相似文献
49.
L Tonella BJ Walsh JC Sanchez K Ou MR Wilkins M Tyler S Frutiger AA Gooley I Pescaru RD Appel JX Yan A Bairoch C Hoogland FS Morch GJ Hughes KL Williams DF Hochstrasser 《Canadian Metallurgical Quarterly》1998,19(11):1960-1971
The combination of two-dimensional polyacrylamide gel electrophoresis (2-D PAGE), computer image analysis and several protein identification techniques allowed the Escherichia coli SWISS-2DPAGE database to be established. This is part of the ExPASy molecular biology server accessible through the WWW at the URL address http://www.expasy.ch/ch2d/ch2d-top.html . Here we report recent progress in the development of the E. coli SWISS-2DPAGE database. Proteins were separated with immobilized pH gradients in the first dimension and sodium dodecyl sulfate-polyacrylamide gel electrophoresis in the second dimension. To increase the resolution of the separation and thus the number of identified proteins, a variety of wide and narrow range immobilized pH gradients were used in the first dimension. Micropreparative gels were electroblotted onto polyvinylidene difluoride membranes and spots were visualized by amido black staining. Protein identification techniques such as amino acid composition analysis, gel comparison and microsequencing were used, as well as a recently described Edman "sequence tag" approach. Some of the above identification techniques were coupled with database searching tools. Currently 231 polypeptides are identified on the E. coli SWISS-2DPAGE map: 64 have been identified by N-terminal microsequencing, 39 by amino acid composition, and 82 by sequence tag. Of 153 proteins putatively identified by gel comparison, 65 have been confirmed. Many proteins have been identified using more than one technique. Faster progress in the E. coli proteome project will now be possible with advances in biochemical methodology and with the completion of the entire E. coli genome. 相似文献
50.
JW Lynch GA Kaplan RD Cohen J Tuomilehto JT Salonen 《Canadian Metallurgical Quarterly》1996,144(10):934-942
Much remains to be understood about how low socioeconomic status (SES) increases cardiovascular disease and mortality risk. Data from the Kuopio Ischemic Heart Disease Risk Factor Study (1984-1993) were used to estimate the associations between acute myocardial infarction and income, all-cause mortality, and cardiovascular mortality in a population-based sample of 2,272 Finnish men, with adjustment for 23 biologic, behavioral, psychologic, and social risk factors. Compared with the highest income quintile, those in the bottom quintile had age-adjusted relative hazards of 3.14 (95% confidence interval (CI) 1.77-5.56), 2.66 (95% CI 1.25-5.66), and 4.34 (95% CI 1.95-9.66) for all-cause mortality, cardiovascular mortality, and AMI, respectively. After adjustment for risk factors, the relative hazards for the same comparisons were 1.32 (95% CI 0.70-2.49), 0.70 (95% CI 0.29-1.69), and 2.83 (95% CI 1.14-7.00). In the lowest income quintile, adjustment for risk factors reduced the excess relative risk of all-cause mortality by 85%, that of cardiovascular mortality by 118%, and that of acute myocardial infarction by 45%. These data show how the association between SES and cardiovascular mortality and all-cause mortality is mediated by known risk factor pathways, but full "explanations" for these associations will need to encompass why these biologic, behavioral, psychologic, and social risk factors are differentially distributed by SES. 相似文献