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The metabolic effects of protein malnutrition on growth and development of the exocrine pancreas are largely unknown. The aim of the present study was to evaluate the effects of protein malnutrition on pancreatic protein and DNA synthesis during postnatal development. Rat dams and their offspring were fed a protein-deficient diet (6% casein) or a control diet (25% casein) during gestation, lactation and after weaning. Pancreatic protein and DNA synthesis were measured in vitro at postnatal ages 1, 3, 10, 23, 36 and 60 days, by assessing [3H]leucine and [3H]thymidine incorporation in freshly isolated acini. Different patterns of protein synthesis were seen in the two groups. At birth, pancreatic protein synthesis was low in both control and malnourished animals. At day 3, protein synthesis in the control acini increased 10-fold while synthesis in acini of the malnourished animal group was only 50% of age-matched control values. No differences in protein synthesis were detected between the control and malnourished groups between 10 and 36 days of age. At 60 days (adulthood), acinar protein synthesis declined in the control-fed rats, but a significant increase was observed in the malnourished animals (p < 0. 0005). At birth, DNA synthesis was high in the acini from both control and malnourished animals. The low-protein diet induced a slight reduction in DNA synthesis at day 3, without altering the general pattern during later stages of development. In conclusion, protein deprivation has variable effects on pancreatic protein and DNA synthesis at different stages of postnatal development. Furthermore, the mechanisms of control within acini appear to be intrinsically regulated. 相似文献
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Although a curable malignancy, testis cancer and its treatment have unique associated morbidities that largely affect reproductive dysfunction. In this focused review, the factors that contribute to infertility in men with testis cancer are outlined. The treatment-specific risks to fertility that accompany cancer management are also discussed. Contemporary methods of overcoming infertility in testis cancer patients are addressed, and several exciting and promising experimental approaches to the preservation or restoration of fertility for men with testis cancer are presented. 相似文献
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Midwestern populations of Coquillettidia perturbans (Walker) and Anopheles quadrimaculatus (Say) were tested for their ability to transmit Cache Valley virus (CV), a recognized human and animal pathogen. Field-collected mosquitoes were fed artificial blood meals containing 5.2-6.2 log10 pfu/ml of CV. After 9-23 d at 28 degrees C, 75-93% of blood-fed Cq. perturbans had disseminated infections and 6-62% transmitted the virus to suckling mice. However, when infected with a lower virus titer (3.3 log10 pfu/ml), only 10-36% of the mosquitoes had disseminated infections and 0-10% transmitted the virus to suckling mice. A similar infection rate (21%) was observed in Cq. perturbans fed on viremic (3.2 log10 pfu/ml) hamsters. An. quadrimaculatus were infected (81-100%) by both doses used, with transmission rates ranging from 13-67% after 16-23 d of incubation. Transmission rates for the laboratory strain An. quadrimaculatus SAVANNAH ranged from 20 to 33% after 7-14 d of incubation. Our data show that although An. quadrimaculatus is more susceptible to CV infections than Cq. perturbans, both mosquito species could be involved in the midwestern transmission cycle of the virus. 相似文献
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PR Evans 《Canadian Metallurgical Quarterly》1976,2(6040):839-841
About one person in four or five is conscious that scratching an irritation may produce an itch elsewhere. The sensation is well localised, comes and goes quickly, and recurs when scratching is repeated a short while later. Scratch and referred itch are ipsilateral; scratching the site of the referred itch does not cause the original spot to itch. Scatching face, palms, or soles does not produce referred itching. Different people stimulated in the same region do not necessarily feel referred itch in the same place. The mechanism of the phenomenon is unknown, though it may be thalamic. 相似文献