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571.
RT Jung MC White NB Bowley G Bydder K Mashiter GF Joplin 《Canadian Metallurgical Quarterly》1982,285(6348):1078-1081
Sixteen young women with hyperprolactinaemia and normal or equivocal sella in radiographs underwent computed tomography using a Siemens Somatom II. In all but one case an abnormality was found. The sella was full in seven and partially empty in nine. A tumour was visible in six of the full and in four of the partially empty sellae. All but one of the 10 tumours was unilateral, and in seven the pituitary stalk was deviated away from the tumour. After administration of intravenous contrast (Urografin) four tumours showed diffuse enhancement, four ring enhancement, and two enhanced less than adjacent normal pituitary tissue. Two of the tumours have been subsequently shown histologically to be prolactinomas. Prolactin response to thyrotrophin-releasing hormone predicted a tumour in seven out of eight with visible tumours but also in three out of four without visible tumours; using metoclopramide, a tumour was predicted in six out of seven with tumours, but again in three out of four without visible tumours. Such results question the value of dynamic tests for the discrimination of tumours. We conclude that practically all women with sustained hyperprolactinaemia and a normal or equivocal sella radiologically have pituitary disease. 相似文献
572.
网友提问酷睿2T5X X X的技术参数?T5600:2M B二级缓存,1.83G H z主频,667M H z前端总线,支持虚拟化技术;T5500:2M B二级缓存,1.66G H z主频,667M H z前端总线,不支持虚拟化技术;另外,最新推出的T5200是降频“缩水”版本,2M B二级缓存,1.6G H z主频,533M H z前端总线,不支持虚拟 相似文献
573.
Anne M. Ruminski Giuseppe Barillaro Charles Chaffin Michael J. Sailor 《Advanced functional materials》2011,21(8):1511-1525
Remote detection of reactive analytes using optical films constructed from electrochemically prepared porous Si‐based photonic crystals is demonstrated. Porous Si samples are prepared to contain either surface oxide or surface Si‐H species, and analyte detection is based on irreversible reactions with HF(aq) or Cl2(g) analytes, respectively. HF dissolves silicon oxide from the porous matrix, causing an irreversible blue‐shift in the resonance peak of the photonic crystal. Cl2 reacts with the native Si‐H species present on the surface of as‐etched porous Si to generate reactive silicon halides that evaporate from the surface and/or react with air to convert to silicon oxide. Either Cl2‐related process reduces the net refractive index of the material that is detected as a blue shift in the spectrum. With sufficient analyte concentrations or exposure times, the spectral blue shifts are visible to the unaided eye. A portion of the porous nanostructure is filled with inert polystyrene, which acts as an internal spectral reference. The polymer fiducial protects that portion of the sensor from attack by the corrosive analytes. Reflectance spectra from both the polymer‐filled and the unfilled, reactive porous layers are acquired simultaneously. The fiducial marker also allows elimination of artifacts associated with shifts of the resonance peak upon changing the angle of incidence of the optical probe. Theoretical angle‐resolved spectra (transfer matrix method) show a good match with the experimental data. High‐temperature air or room‐temperature ozone oxidation reactions are used to prepare the HF‐reactive surface, and it is found that the ozone oxidation reaction produces a greater sensitivity to HF (LLOD of 0.1% HF in water). 相似文献
574.
Don B. Chaffin Leslie S. Gallay Charles B. Woolley Stephen R. Kuciemba 《International Journal of Industrial Ergonomics》1986,1(2)
Though worker training is often chosen as a means to reduce the risk of low back pain if involved in lifting activities, the effect on a worker's lifting posture is rarely reported. This paper describes a video analysis method of recording lifting postures and the results of one evaluation of a training program specifically designed to modify lifting postures. It is concluded that a four-hour training program had beneficial but minor effects on the lifting techniques used by healthy workers in a warehouse when handling relatively light to moderate loads (i.e., 85% of loads lifted were below 30 pounds). 相似文献