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HF Frierson MJ Gaffey LR Zukerberg A Arnold ME Williams 《Canadian Metallurgical Quarterly》1996,9(7):725-730
The deregulation of cyclin D1 (BCL-1, PRAD1, CCND1) protein, normally synthesized in the G1 phase of the cell cycle, has been implicated in the pathogenesis of some malignant neoplasms, including invasive mammary carcinomas. We used rabbit polyclonal antibody 19 to detect cyclin D1 in 55 infiltrating ductal carcinomas and compared the findings to six important clinicopathologic parameters and cyclin D1 gene amplification. Nuclear immunoreactivity of variable intensity for cyclin D1 was present in 35% of the neoplasms, whereas immunoreactivity of normal mammary epithelial nuclei was absent. No significant correlations were observed between immunoreactivity and patient age, axillary lymph node status, estrogen receptors, progesterone receptors, histologic grade, or any of its three components. There was a correlation between cyclin D1 immunostaining and tumor size (P = 0.013). Fourteen of 15 tumors 2 cm or less were negative, whereas 7 of 12 neoplasms larger than 4 cm were immunopositive. Fifteen percent of the invasive carcinomas had cyclin D1 gene amplification. Of these eight tumors, six showed cyclin D1 immunoreactivity (P = 0.017). In this study, cyclin D1 was detected immunohistochemically in approximately one-third of infiltrating ductal carcinomas; approximately one-third of these had detectable cyclin D1 gene amplification. These results further implicate cyclin D1 in breast tumorigenesis and are additional evidence for the role of cell cycle regulatory proteins in invasive mammary carcinoma. 相似文献
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Some mute swans have been found to have higher levels of radio-iodine in their thyroids than farm and wildlife animals. In the East Midlands of the U.K., elevated levels were confined to swans inhabiting major rivers like the Trent and Soar where the highest values occurred in thyroids collected downstream from sewage and water reclamation works. Comparing the concentrations of 125I and 131I in blanket weed, which is a food source of the swan, and river water samples collected from above, below and in such effluents, showed that radio-iodine enters the river via these routes. The environmental pathway is sewage effluent--(water reclamation)--river water--river weed--swan. The radioactivity originates from the widespread use of radio-iodine in hospitals and analytical laboratories where much of the liquid and soluble waste is discarded into the sewage drain system. With a simple counting assembly consisting of a heavily shielded thin NaI(Tl) crystal detector attached to a 2-channel scaler-timer it was possible to check large numbers of swan thyroid glands. Although relatively high count rates were frequently obtained the levels of radio-iodine in thyroids were too low to affect the health and well-being of the swan. 相似文献
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Previous results, using a passive transfer assay, have shown that recrudescences of Plasmodium chabaudi chabaudi AS strain are antigenically different from the infecting parental population and also that the recrudescence appears to be a mix of antigenic types. This present study examines further these recrudescent populations using an indirect fluorescent antibody test on live, schizont-infected red blood cells. This analysis shows that ten clones derived from a recrudescence are all antigenically different from the parent population and that some are different from each other. The use of this method to examine the antigenic types of recrudescent clones after transmission through mosquitoes also demonstrates a resulting change in antigenicity. Such results showing a link between mosquito transmission and varying antigenicity may have important implications in terms of immunity and vaccine development. 相似文献
98.
Despite the fact that the neuroleptic drugs have been widely used for more than 40 years, one of their most common side-effects, akathisia, has been relatively neglected. There are still no universally agreed diagnostic criteria for akathisia, particularly chronic akathisia, and in this review article, we discuss the controversies surrounding the voluntary nature of its motor features and the importance of the dysphoric component. We also review the published epidemiological studies to show the great variation in frequency of occurrence. Finally, we discuss the possible neurotransmitters involved in the pathophysiology and treatment of this condition. 相似文献
99.
The influence of various design parameters on the cogging torque developed by permanent magnet machines is investigated. It is shown that the slot and pole number combination has a significant effect on the cogging torque, and influences the optimal value of both skew angle and magnet arc, as well as determining the optimal number of auxiliary teeth/slots. A simple factor, which is proportional to the slot number and the pole number and inversely proportional to their smallest common multiple, has been introduced to indicate the “goodness”β of the slot and pole number combination. In general, the higher the “goodness” factor the larger the cogging torque 相似文献
100.
Zhu Z.Q. Ruangsinchaiwanich S. Howe D. 《Industry Applications, IEEE Transactions on》2006,42(3):650-657
A simple analytical technique is proposed to synthesize the cogging-torque waveform of a permanent-magnet brushless machine from the cogging torque, which is associated with a single stator slot. An analytical expression is derived, which reveals the relationship between the two. It is then applied to two motors, which have a fractional number of slots per pole. It is shown that the resultant cogging-torque waveform can be synthesized to a high accuracy, as confirmed by both finite-element analysis and measurements. It is also shown that not all the cogging-torque harmonics that exist in the cogging-torque waveform due to a single slot will be present in the resultant cogging torque, and that the most significant components can be identified analytically. 相似文献