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21.
Hereditary hypertriglyceridemic rats (hHTg) were developed as a new genetic model for the study of relationships between blood pressure (BP) and metabolic abnormalities. This strain has been produced by selective inbreeding from Wistar rats according to the rise of plasma triglycerides induced by a high-sucrose diet. Though hHTg rats display hypertriglyceridemia, impaired glucose tolerrance, hyperinsulinemia, insulin resistance and increased BP even without nutritional stimuli, high sucrose feeding further aggravates these symptoms. High plasma triglycerides levels in hHTg rats seem to be a consequence of their hyperproduction. Impaired insulin action is responsible for the defective glucoregulation in this strain. The loss of insulin responsiveness might be due to a reduction in the number of glucose transporters. Highly significant relationships among plasma triglycerides, ouabain-resistant Na+ transport and BP were demonstrated in the hHTg rats. Segregating populations (F2 hybrids) should be used for genetic analysis of the primary role of lipid and/or ion transport abnormalities in the pathogenesis of this form of genetic hypertension.  相似文献   
22.
Interleukin-1 (IL-1) is a cytokine produced by the macrophage-monocyte system that has important effects on immunological responses and inflammatory reactions. Several clinical studies have shown that severe protein energy malnutrition adversely effects cell-mediated immune responses and the functional state of macrophages. The objective of this study was to analyse IL-1 production by adherent cells stimulated in vitro with lipopolysaccharide B (LPS) from patients with alcoholic cirrhosis of the liver and its possible relationship with nutritional states. Forty-five patients with alcoholic cirrhosis and 28 healthy donors were investigated. A combined index of nine anthropometric and biochemical parameters was used to evaluate nutritional status of cirrhotic patients, allowing a distinction to be made between those patients with acceptable nutrition (group I: 40%), those with slight malnutrition (group II: 37.7%), and those with severe malnutrition (group III: 22.3%). IL-1 activity was significantly lower in the cirrhosis patients than in the controls (P less than 0.001). This activity also was significantly lower in samples obtained from cirrhotics with severe malnutrition than in those with acceptable nutrition (P less than 0.05); the combined index and the sole anthropometric index gave the same results, suggesting that malnutrition may play a role in the immunoregulatory disturbances in the pathogenesis of alcoholic liver disease.  相似文献   
23.
Summary We used a combination of genetic hybridization analysis and electrokaryotyping with radioactively labelled MEL1 gene probe hybridization to isolate and identify seven polymeric genes for the fermentation of melibiose in strain CBS 5378 of Saccharomyces cerevisiae (syn. norbensis). Four of the MEL genes, i.e. MEL3, MEL4, MEL6 and MEL7, were allelic to those found in S. cerevisiae strain CBS 4411 (syn. S. oleaginosus) whereas three genes, i.e. MEL8, MEL9 and MEL10 occupied new loci. Electrokaryotyping showed that all seven MEL genes in CBS 5378 were located on different chromosomes. The new MEL8, MEL9 and MEL10 genes were found on chromosomes XV, X/XIV and XII, respectively.  相似文献   
24.
The pharmacokinetics and metabolism of 4-demethoxydaunorubicin (idarubicin, IDA) were studied in 21 patients with advanced cancer after i.v. (12 mg/m2) and oral (30-35 mg/m2) treatment according to a balanced crossover design. Patients were divided into four groups: subjects who showed normal liver and kidney function (group N), those who presented with normal kidney function and liver metastases (group L), those with kidney dysfunction (creatinine clearance, less than or equal to 60 l/h; group R), and those with both liver and kidney dysfunction (group LR). Five patients showed variations in liver or kidney function after the first treatment and were considered to be nonevaluable for the crossover study but evaluable for the liver/kidney function study; some of them appeared in different groups for the i.v. as opposed to p.o. treatments. After i.v. administration, IDA plasma levels followed a triphasic decay pattern. The main metabolite observed in all patients was the 13C-reduced compound (IDAol), which attained plasma levels 2-12 times higher than those of the parent compound. IDA pharmacokinetics was not dependent on the presence of liver metastases but was related to the integrity of kidney function. Analysis of variance indicated a significant correlation between IDA plasma clearance and creatinine clearance; it was also found that IDA plasma clearance was lower in patients whose creatinine clearance was less than 60 ml/min [group N, 122.8 +/- 44.0 l/h; group L, 104.4 +/- 27.7 l/h (P = 0.58) vs group R, 83.4 +/- 18.3 l/h (P = 0.037)]. The IDAol terminal half-life and mean residence time (MRT) were significantly increased in patients with impaired kidney function [MRT: group N, 63.6 +/- 10.8 h; group L, 69.9 +/- 10.2 h (P = 0.27) vs group R, 83.2 +/- 10.9 h (P = 0.025) and t1/2 gamma: group N, 41.3 +/- 10.1 h; group L, 47.0 +/- 7.4 h (P = 0.31) vs group R, 55.8 +/- 8.2 h (P = 0.025)]. After oral treatment, drug absorption occurred during in the first 2-4 h after IDA administration; a biphasic decay pattern was observed thereafter. The main metabolite observed in all patients was again IDAol. The AUC of IDAol was greater after oral administration than after i.v. treatment in proportion to the AUC of IDA (i.v.: AUC-IDAol/AUC-IDA, 2.4-18.9; p.o.: AUC-IDAol/AUC-IDA, 4.1-21.4). Following oral dosing, a substantial amount of 4-demethoxydaunomycinone (AG1) was found in 11/21 patients.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
25.
732 workers from several loudest production departments in a pottery plant were examined. The noise level measurements were carried out at a regular course of work. Auditory sensitivity threshold was determined via air conduction, at frequencies of 250, 500, 1000, 2000, 4000 and 8000 Hz. Functioning of the organ of hearing under conditions of noise at the workplace was analysed. The influence of several noise levels--up to 85 dB/A/ and higher, and the relation between the length of service and hearing sensitivity threshold were investigated. The largest exposures were recorded in the batching and milling plant, sorting and kilns departments.  相似文献   
26.
ABSTRACT: A case study of the creation and implementation of a four-tier, integrated system of health care services in a sparsely populated, rural province in Argentina is described and discussed. Begun in 1970 in a diverse geographical area with a tradition of poor health status and inadequate health care resources, the provincial government set out to develop the human, physical and technological resources needed to provide a system of preventive and curative services appropriate to the health care needs of its residents. Innovative programs included training in management techniques, and epidemiological perspective of high risk, an emphasis on personnel development through a rural general medicine residency and an expanded nursing program as well as programs to attack infectious diseases, poor sanitation and dental problems were all developed in response to the distinctive features of the physical and social environment of the province. Improvements in traditional health indicators are reviewed and attributed to the program and administrative structures that were developed.  相似文献   
27.
The pattern of pre- and postnatal appearance of 5-HT1D receptors throughout the different areas of the human brain was studied by quantitative in vitro autoradiography, using [125I]GTI (serotonin O -carboxymethyl-glycyl-[125I]tyrosinamide) as a ligand. The anatomical distribution of 5-HT1D receptors in neonatal, infant and children's brain was in good agreement with that observed in the adult, the basal ganglia and substantia nigra being the most intensely labelled areas. The development of these receptors throughout the human brain was mainly postnatal: low densities of [125I]GTI binding sites were observed at the fetal/neonatal stage in most regions analyzed, in contrast with the high levels of labelling found in infant and children's brains. Indeed, in a number of regions, including the globus pallidus, substantia nigra and visual cortex, a peak of overexpression of 5-HT1D receptors was observed in the first decade of life. Such overexpression could support a regulatory role for 5-HT1D receptors in advanced periods of the CNS developmental process. Our results also indicate that the administration of drugs acting on 5-HT1D receptors during the early postnatal period of life could result in modifications of their properties, as these receptors are already functional in this period.  相似文献   
28.
The aim of this research was to quantify sleep problems in patients suffering from Parkinson's disease by means of the new Parkinson's Disease Sleep Scale (PDSS) and to correlate such problems with the possible influence of current drug treatment. A total of 70 patients (36 men and 34 women) with a diagnosis of Parkinson's disease were enrolled. Their mean age was 69.7 +/- 8.2 years, and duration of disease was 7.4 +/- 4.8 years. All patients completed the PDSS and the Unified Parkinson's Disease Rating Scale (UPDRS Parts I-IV). Drug consumption and doses were registered. The mean score on the PDSS scale was 109.23 +/- 19.75 and on the UPDRS III scale was 25.24 +/- 11.35. The lowest scores were obtained in Item 3 (sleep fragmentation): 5.53 (2.46); and in Item 8 (nocturia): 5.75 (2.91). There was a weak correlation between the PDSS and UPDRS III (cc = -0.355, P = 0.003), PDSS and UPDRS I (cc = -0.272, P = 0.02), and PDSS and UPDRS IV (cc = -0.416, P < 0.001). Motor conditions, mental state, and drug complications influence sleep quality. Although this effect was significant, it was not of a great magnitude. Dopaminergic drugs did not increase daytime sleepiness. As a whole, sleep quality in patients who took dopaminergic agonists did not differ from that of patients who took levodopa in monotherapy.  相似文献   
29.
Eighty-four postmenopausal women who were randomly allocated to one of four groups, completed a 1 year follow-up. The first group (n = 20) received 0.625 mg/day conjugated estrogens cyclically (CE; 25 days/month). The second (n = 23) received 0.625 mg/day of CE continuously, and the third (n = 17) received 50 micrograms/day of transdermal 17 beta-estradiol cyclically (24 days/month). All these groups also received 2.5 mg of medroxiprogesterone acetate sequentially for the last 12 days of hormone replacement therapy, while the fourth group (n = 24) constituted a treatment-free control group. Dual photon absorptiometry was carried out before therapy and was repeated after 1 year. Serum calcium, phosphate and osteocalcine levels, and the urinary calcium/creatinine and hydroxyproline/creatinine ratios, were measured prior to treatment and 6 and 12 months thereafter. All treatment groups showed an increase in bone mineral content. This increase was higher in the continuous CE treatment group (4.4%, P less than 0.05) and in transdermal group (7.1%, P less than 0.01). Concomitant biochemical effects at 6 and 12 months, reduction in urine calcium and hydroxyproline, reduction in blood calcium, phosphate and osteocalcine, were compatible with the observed effects on bone mineral.  相似文献   
30.
Loss of heterozygosity for distal markers on 22q in human gliomas.   总被引:5,自引:0,他引:5  
Loss of constitutional heterozygosity as determined through the analysis of restriction-fragment-length polymorphism (RFLP) on tumoral and constitutional DNA has proven to be helpful to delimit the location of tumor-suppressor genes in the human genome. In malignant gliomas this approach indicates that chromosomes 9p, 10, 17p, and 22 may contain genes of this category involved in its origin and/or progression. Regarding chromosome 22, the data so far provided by molecular studies confirmed those previously reported by cytogenetic studies, suggesting the existence of a sub-group of malignant gliomas characterized by monosomy of this chromosome. However, the precise location of the putative glioma suppressor gene on chromosome 22 remains ambiguous. We have performed a combined cytogenetic and RFLP study on a series of 31 gliomas, looking for structural abnormalities of this chromosome. In 3 instances, terminal deletions of the long arm of chromosome 22 were observed by both methodologies, suggesting that the band q13 region distal to the D22S80 marker might be the critical domain non-randomly involved in tumor suppression of gliomas.  相似文献   
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