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61.
Seasonal abundance of phytoplankton has been discussed in three tropical ponds of Hyderabad, India during two years of investigation. The observed patterns have been characterized as seasonal maxima and minima during summer, monsoon and winter. The tropical patterns observed in the study ponds were typical but different from those observed in temperate regions. Most of the maxima were observed in winter and the minima during the monsoon or rainy season. Diatomeae dominated the phytoplankton of all the ponds in all seasons. An inverse relationship between Diatomeae and Cyanophyta, and Diatomeae and Euglenineae was observed. The phytoplankters have been grouped as perennial, summer, monsoon and winter species.  相似文献   
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Elevated levels of animal waste-borne pathogen in ambient water is a serious human health issue. Mitigating influx of pathogens from animal waste such as dairy manure to soil and water requires improving our existing knowledge of pathogen reductions in dairy manure treatment methods. This study was conducted to enhance the  understanding of human pathogen decay in liquid dairy manure in anaerobic (AN) and limited aerobic (LA) storage conditions. The decay of three pathogens (Escherichia coli, Salmonella spp., and Listeria monocytogenes) was assessed in bench-scale batch reactors fed with liquid slurry. A series of temperatures (30, 35, 42, and 50 °C) conditions were tested to determine the impacts of temperature on Escherichia coli, Salmonella, and L. monocytogenes decay in AN and LA conditions. Results showed prolonged survival of E. coli compared to Salmonella and L. monocytogenes in both LA and AN environments. Variations in survival among pathogens with temperature and environmental conditions (i.e., LA and AN) indicated the necessity of developing improved dairy manure waste treatment methods for controlling animal waste-borne pathogens. The results of this study will help in improving the current understanding of human pathogen decay in dairy manure for making informed decisions of animal manure treatment by stakeholders.  相似文献   
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There currently is little information available that allows objective prediction of psychosocial risks and benefits associated with the shift work in the developing countries. To provide such information, this study assessed possible differential effects of fatigue associated with the shift workers' attitude, job satisfaction, psychosocial problems, and other difficulties. Data were collected from the subjective responses on various scales using questionnaire among sixty adult male subjects working on a weekly rotating three-shift system in a shoe factory in Bangladesh. The results indicated that shift work is associated with negative aspects of disturbing their family, conjugal and social lives, curtailed leisure activities, created difficulties in meeting their friends, caused irregularity of their mealtime, affected sleep and caused health problems. However, the effect is significant only for such feelings of social and family aspects, as well as sleepy and lively hood but no significant main effects of shift schedule are observed for any of the behavioural and organizational context.  相似文献   
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The effects of 2 oral contraceptives, Ovulen and Norlestrin, were studied in monkeys fed adequate protein and low protein diets. The experiment was carried out in parts. In the first one, the administration of contraceptives was cyclic and similar to that employed in human subjects. In the other experiments, the contraceptives were given continuously and an attempt was made to exaggerate the deleterious effects of the oral contraceptive on the liver by including small doses of a known hepatotoxic agent, aflatoxin (AT). In Experiment 1, 45 female monkeys were divided into 2 groups of 20 and 25 and received an adequate protein (16%) and low protein diet (4%) respectively. Each monkey was fed 1/5 of a tablet of Ovulen or Norlestrin orally for 3 weeks, and then administration was discontinued for 1 week. In Experiment 2, 35 female monkeys were divided into 7 groups of 5 each. All the animals recieved 4% protein diet. 5 groups were tube fed at the rate of 100 cal/kg body weight, while 2 groups were given diet ad libitum. Group I received the diet alone while groups II-V received 10 mcg AT, 25 mcg AT, 10 mcg AT plus 1/5 Ovulen tablets, and 25 mcg AT plus 1/5 Ovulen tablet respectively daily. Groups VI and VII received the diet ad libitum but were orally fed 75 mcg AT and 75 mcg AT plus 1/5 Ovulen tablet respectively. Serum glutamic-oxalacetic transaminase activity and alkaline phosphatase activity were studied at regular intervals after the administation of oral contraceptives in the experiments. Serum proteins and hemoglobin were also determined. Monkeys fed oral contraceptives showed increased serum glutamic-oxalacetic transaminase and alkaline phosphatase activities irrespective of the level of protein in the diet. Livers of animals receiving oral contraceptives were morphologically similar to the controls fed respective diets. The experiments were conducted for a period of almost 2 years.  相似文献   
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