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541.
The effects of a diet rich in fish oil on arterial blood pressure, body weight, left ventricular weight and heart rate have been investigated in 8 month old spontaneously hypertensive male rats (SHR) as compared to age-matched hypertensive controls. A diet containing 10% fish oil decreased blood pressure by about 40 mmHg within 20 days of starting the experiment, and this effect persisted over the observation period of 80 days. Permitting the animals free access to food, the body weight of the diet group increased by 25%. The degree of hypertrophy as evaluated by relating left ventricular weight to tibial length was significantly reduced (10%) in the diet fed group. Heart rate was increased by 53%. The study demonstrates that a diet rich in fish oil can lower arterial blood pressure over several weeks without a recognizable loss in function despite a considerable increase in body weight. It can be assumed that a more marked regression of left ventricular hypertrophy is counteracted by a reflex increase in sympathetic efferentation to the heart.  相似文献   
542.
543.
Stromal sarcoma of the breast, according to current concepts, is a rare lesion arising from the stroma surrounding the ductal epithelium. A case of this neoplasm is reported, with light and electron microscopic findings in fine needle aspirates and correlation with histologic findings. The findings, similar to those previously reported for stromal sarcoma of the breast, included a less-pleomorphic morphologic picture than is seen in malignant fibrous histiocytoma, but a more primitive ultrastructural appearance.  相似文献   
544.
Cloning of uvrA, lexC and ssb genes of Escherichia coli.   总被引:19,自引:0,他引:19  
The L' subunits, phosphorylatable precursors of L-type pyruvate kinase, can be proteolyzed in vivo and in vitro, and transformed into several molecular species.Trypsin induces the appearance of a phosphorylatable form similar to liver L-type enzyme.Subtilisin splits the phosphorylatable site and induces the appearance of a form similar to the minor form occuring with red cell aging.Sensitivity to proteolysis of some pyruvate kinase variants is modified.  相似文献   
545.
Histolyn-CYL, a yeast phase skin-test reagent, was administered to 85 histoplasmin-sensitive subjects living in the United States and South America. In a multicenter study, sera were obtained at the time the skin tests were read and again 3 weeks later. In no instance did the skin test induce significant complement-fixing antibody changes or antibodies detected by immuno-diffusion.  相似文献   
546.
Purification and analysis of RNA from paraffin-embedded tissues   总被引:7,自引:0,他引:7  
We have developed methods for the purification and analysis of RNA from formalin-fixed and paraffin-embedded tissue. The methods allow retrospective analysis of gene expression or viral infection. RNA extraction uses prolonged solubilization of tissue with detergent and protease in the presence of high concentrations of a ribonuclease inhibitor. The purified RNA is moderately degraded but its hybridization behavior is essentially unaffected. We were able to quantify specific mRNAs by dot-blot hybridization.  相似文献   
547.
To define the physiological signals involved in the redirection of myosin expression in the swim-exercised rat, the relative influence of thyroid hormones and beta-adrenergic blockade was determined. Swimming exercise resulted in an increased proportion of myosin V1 (60.9 +/- 9.7 vs. 38.0 +/- 4.1% of sedentary rats fed ad libitum) but did not increase serum concentrations of total and free thyroxine or triiodothyronine determined either 17-21 h or immediately after swimming. The proportion of V1 increased, although intermittently food-deprived rats with the body weight of swimming rats exhibited a reduced proportion of V1 (23.5 +/- 2.7). When swimming rats had only intermittent access to food, they had reduced concentrations of all thyroid hormones, but the proportion of V1 (51.5 +/- 7.6) was nonetheless increased. Thus the redirection of myosin expression cannot be attributed to an increased secretion of thyroid hormones. The influence of the adrenergic system was assessed by treating swimming rats with the beta-blocking drug atenolol. Because the proportion of V1 was reduced, but thyroid hormones were not affected, beta-adrenergic blockade seems to influence myosin expression independently of thyroid hormones.  相似文献   
548.
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