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1.
T. Lingaraja P. Sasi Bhushana Rao V. K. Venugopalan 《Environmental Biology of Fishes》1979,4(1):83-88
Synopsis Experiments were carried out to study the feeding rates of the predator fish Therapon jarbua (Forsk) on mullet juveniles, before and after treatment with DDT. Mullet juveniles treated with a subacute concentration, were refused by the control predators, whereas predators treated with a subacute concentration consumed more mullet juveniles. In the present study crescent perch T. jarbua were exposed to subacute and acute concentrations of DDT, and their behaviour was compared with that of the control predators. There were changes in oriented behaviour and co-ordinated movements, and in feeding, aggression and comfort behaviour of the fish. Inflammation in the gills, and caudal fin serration, were noticed in treated fishes. The findings presented here throw light on fundamental pathways by which pollutants interact with the behaviour of fishes. 相似文献
2.
A number of acute phase proteins were determined by electroimmunoassay in media from CBA mouse hepatocytes cultured for 2 days with human recombinant IFN beta 2/IL-6, as well as with conditioned media from LPS-stimulated rat macrophages, and of murine L fibroblasts. It was found that human recombinant IL-6 caused three-fold increase in secretion of fibrinogen, while haptoglobin, complement C3 and transferrin were increased respectively, to 168 per cent, 151 per cent, and 145 per cent of the control. DEX(10(-7) M) in DMEM supplemented with 5 per cent FCS, enhanced the IL-6 effect on the three positive acute phase proteins. IL-6 elevated haptoglobin mRNA in mouse hepatocytes to a degree comparable with the concentration of the protein in the culture medium. The effect of conditioned media from murine fibroblasts and peritoneal rat macrophages was generally similar to that of recombinant IL-6. However, both natural preparations of the cytokines caused decrease in albumin and alpha-1-proteinase inhibitor secretion. 相似文献
3.
Lyle M. Hubinger Laurel Traeger Mackinnon 《European journal of applied physiology and occupational physiology》1992,65(6):555-560
Fifteen middle-aged, untrained (defined as no regular exercise) men (mean age 49.9 years, range 42-67) cycled on a cycle ergometer at 50 rpm for 30 min at an intensity producing 60% predicted maximum heart rate [(fc,max), where fc,max = 220 - age]. Total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and triglyceride (Tg) concentrations were measured from fasting fingertip capillary blood samples collected at rest, after 15 and 30 min of exercise, and at 15 min post-exercise. The mean HDL-C level increased significantly from the resting level of 0.85 mmol.l-1 to 0.97 mmol.l-1 (P < 0.05) after 15 min of exercise, increased further to 1.08 mmol.l-1 (P < 0.01) after 30 min of exercise and remained elevated at 1.07 mmol.l-1 (P < 0.01) at 15 min post-exercise. These increases represented changes above the mean resting level of 14.1%, 27.1% and 25.9% respectively. The HDL-C/LDL-C ratio increased significantly from a resting ratio of 0.20 to 0.26 after 30 min of exercise (P < 0.01) and to 0.24 at 15 min post-exercise (P < 0.05). The mean Tg level increased significantly from a resting level of 0.88 mmol.l-1 to 1.05 mmol.l-1 after 15 min, and to 1.06 mmol.l-1 after 30 min of exercise (P < 0.05 at each time). The TC/HDL-C ratio decreased significantly (P = 0.05) after 30 min of exercise and at 15 min post-exercise by 18.8% and 14%, respectively. No significant changes were observed in the levels of TC or LDL-C over time.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
4.
Anil K. Sinha V. Ann Linscombe B. Bhaskar Gollapudi George C. Jersey Colin N. Park 《Cell biology and toxicology》1985,1(4):333-342
Sister chromatid exchanges (SCE) were analyzed in peripheral blood lymphocytes from a select group of 71 healthy men, 56 nonsmokers and 15 cigarette smokers. In addition to estimating baseline SCE, data were examined to seek relationships of SCE frequencies to age and smoking. The baseline value of 7.53 SCE per cell from the 56 nonsmokers was within the range (5.60 to 9.10 SCE/cell) reported for other human populations. No relationship was found between the mean SCE frequency per cell and age. However, a significant increase in the SCE mean value was observed in smokers as compared to nonsmokers. The results of this study are compared with those of other reports on SCE effects of age and smoking.Abbreviations BUdR
5-bromo,2-deoxyuridine
- SCE
sister chromatid exchange 相似文献
5.
通过对80例急性脑出血死亡组分析,发现死于脑疝的占62.5%,脑疝与一种或二种以上合并症同存者占77.5%,显著高于存活组(P<0.01).它们互为因果,加速死亡。因此,应重视早期或超早期采用简易定向锥颅脑内血肿碎吸术吸除血肿,同时注意维持生命体征稳定,加强脱水降颅压,预防、控制合并症等综合治疗。且要全面分析,相互兼顾,正确处置。这是帮助机体渡过调控障碍难关,挽救生命的有效治疗措施。 相似文献
6.
J. Iba?ez R. Rama M. Riera M. T. Prats L. Palacios 《European journal of applied physiology and occupational physiology》1993,67(1):7-13
The effect of severe acute hypoxia (fractional concentration of inspired oxygen equalled 0.104) was studied in nine male subjects performing an incremental exercise test. For power outputs over 125 W, all the subjects in a state of hypoxia showed a decrease in oxygen consumption (
O2) relative to exercise intensity compared with normoxia (P < 0.05). This would suggest an increased anaerobic metabolism as an energy source during hypoxic exercise. During submaximal exercise, for a given
O2, higher blood lactate concentrations were found in hypoxia than in normoxia (P < 0.05). In consequence, the onset of blood lactate accumulation (OBLA) was shifted to a lower
O2 (
O2 1.77 l·min–1 in hypoxia vs 3.10 l·min–1 in normoxia). Lactate concentration increases relative to minute ventilation (
E) responses were significantly higher during hypoxia than in normoxia (P < 0.05). At OBLA,
E during hypoxia was 25% lower than in the normoxic test. This study would suggest that in hypoxia subjects are able to use an increased anaerobic metabolism to maintain exercise performance. 相似文献
7.
The effectiveness of command-and-control policies related to tobacco use has been studied in high-income countries. Still, there is limited evidence of their effects in low and middle-income countries. We explore the case of Colombia, a country that introduced a business-supported smoking ban in bars and restaurants and all public indoor spaces in 2010. This paper investigates the effect of smoking bans in bars and restaurants on smoking prevalence in Bogotá, Colombia. In this paper, we use the matching with triple-differences technique in analyzing household consumption data from the 2007 and 2011 quality of life surveys. This is done by exploiting their geographical proximity and variation in the density of commercial areas. We found that after the smoking ban implementation, smoking prevalence reduced in households near high-density commercial blocks compared to households near low-density commercial blocks (−10.8 pp.). The impact is larger for households with children and older household heads. Since households near high-density commercial blocks are more frequently exposed to smoking than households near low-density commercial blocks, the former would be more willing to internalize the smoking de-normalization process. 相似文献
8.
9.
《Revista espa?ola de geriatría y gerontología》2023,58(6):101388
Background and objectiveMore than half of institutionalized older people need a emergency department visit annually, with high resources consumption and higher risk of adverse events, due to high complexity. Direct admission to Acute Geriatric Unit (AGU), after geriatric consultant and nursing home medical team assessment, could be a safety and effective alternative to emergency department (ED) admission.MethodsRetrospective observational study of AGU patients admitted by Nursing Home Geriatric Team between January, 1st and December, 31st, 2021. Planned admissions and SARS-CoV-2 positive patients were excluded. Medical (sociodemographic, clinical, functional and cognitive) records and outcomes data (inpatient mortality, hospital and ED lenght of stay, transfer to ED and delirium within 48 h after admission, hospital discharge location) were collected.ResultsTwo hundred and six patients directly admitted, 101 through ED (N 307). 62.5% with Barthel index <40, 65% with dementia, 56.4% with Charlson index ≥3. Inpatient mortality was 14.6% in direct admission, 20.8% in ED referral group, p = 0.14. Hospital lenght of stay was 9.61 ± 6.01 days in direct admission, 11.22 ± 5.36 days in ED group, p = 0.02. 27.7% of patients with delirium in direct admission and 36.6% in ED group; only one patient was transferred to ED, within 48 h after admission.ConclusionsDirect admission is a safety and effective alternative to ED referral in institutionalized older people after geriatric assessment, due to no increased mortality, shorter length of stay and hospital cost reduction. 相似文献
10.
Summary Data are reviewed on the amino acid metabolism in patients suffering from transient acute polymorphic psychoses according to ICD-10. The psychotic episodes of many of these patients are characterized by distorted sensory perceptions and intense emotional states; plasma amino acid analysis revealed a disturbed serine-glycine metabolism.In remitted patients oral loading with serine induced the characteristic dysperceptions and psychedelic symptoms. Plasma concentrations of serine and methionine were decreased, and the concentration of taurine was increased. Fibroblast experiments suggest that the activities of the serine metabolizing enzymes serine hydroxymethyltransferase and cystathionine-synthase are increased in these patients.The determination of plasma amino acid concentrations proved to be useful in discriminating these patients. The prevalence of this transient psychosis in a psychiatric in-patient population ranged between 1.4 and 3.6%. 相似文献