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991.
N Lurie J Slater P McGovern J Ekstrum L Quam K Margolis 《Canadian Metallurgical Quarterly》1993,329(7):478-482
BACKGROUND: Emphasis on ensuring women's access to preventive health services has increased over the past decade. Relatively little attention has been paid to whether the sex of the physician affects the rates of cancer screening among women. We examined differences between male and female physicians in the frequency of screening mammograms and Pap smears among women patients enrolled in a large Midwestern health plan. METHODS: We identified claims for mammography and Pap tests submitted by primary care physicians for 97,962 women, 18 to 75 years of age, who were enrolled in the health plan in 1990. The sex of the physician was manually coded, and the physician's age was obtained from the state licensing board. After identifying a principal physician for each woman, we calculated the frequency of mammography and Pap smears for each physician, using the number of women in his or her practice during 1990 as the denominator. Using unconditional logistic regression, we also calculated the odds ratio of having a Pap smear or mammogram for women patients with female physicians as compared with those with male physicians, controlling for the physician's and the patient's age. RESULTS: Crude rates for Pap smears and mammography were higher for the patients of female than male physicians in most age groups of physicians. The largest differences between female and male physicians were in the rates of Pap smears among the youngest physicians. For the subgroup of women enrolled in the health plan for a year who saw only one physician, after adjustment for the patient's age and the physician's age and specialty, the odds ratio for having a Pap smear was 1.99 (95 percent confidence interval, 1.72 to 2.30) for the patients of female physicians as compared with those of male physicians. For women 40 years old and older, the odds ratio for having a mammogram was 1.41 (95 percent confidence interval, 1.22 to 1.63). For both Pap smears and mammography, the differences between female and male physicians in screening rates were much more pronounced in internal medicine and family practice than in obstetrics and gynecology. CONCLUSIONS: Women are more likely to undergo screening with Pap smears and mammograms if they see female rather than male physicians, particularly if the physician is an internist or family practitioner. 相似文献
992.
An audit of the treatment procedures routinely adopted by maxillofacial and oral surgeons for the removal of impacted third molars under general anaesthesia was undertaken in South Africa. Most maxillofacial and oral surgeons agree on the method of bone removal, the prescribing of antibiotics, analgesic agents and mouthwashes, the suturing of the incision wound and the post-operative review of patients. The results were compared to a similar study undertaken by Falcon and Roberts (1992) in the UK. With the exception of the method of bone removal, maxillofacial and oral surgeons in both groups share a similar approach to the treatment procedures adopted in the removal of impacted third molars. Some variability, however, existed in both studies with regard to the use of intra-operative local anaesthetic agents, the administration of peri-operative steroids and the use of non-steroidal anti-inflammatory agents. 相似文献
993.
Feng G.-L. Rao T.R.N. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》1993,39(1):37-45
A simple decoding procedure for algebraic-geometric codes C Ω(D ,G ) is presented. This decoding procedure is a generalization of Peterson's decoding procedure for the BCH codes. It can be used to correct any [(d*-1)/2] or fewer errors with complexity O (n 3), where d * is the designed minimum distance of the algebraic-geometric code and n is the codelength 相似文献
994.
A. Matsumura J. M. Fernndez T. J. Thornton S. N. Holmes J. Zhang B. A. Joyce 《Solid-state electronics》1996,40(1-8):399-403
We have characterized two-dimensional electron gases (2DEGs) in Si/SiGe modulation doped structures grown by gas source molecular beam epitaxy. Hall bar structures were fabricated to characterize the structures and magnetotransport measurements were carried out at temperatures down to 0.4 K. Pronounced Shubnikov-de Haas oscillations were observed in the longitudinal magnetoresistance, indicative of high quality 2DEG in the channel. Electron mobilities up to 87,000 cm2 V−1 s−1 with sheet densities about 7 × 1011 cm−2 were obtained at low temperature. Dingle plots of the magnetoresistance vs reciprocal magnetic field were utilized to determine the single-particle relaxation times in order to investigate scattering mechanisms in these structure. The ratio of the transport scattering time derived from electron mobility to the single-particle relaxation time is of the order of 10, indicating that remote impurity scattering is a dominant factor limiting the mobility of our structures. The behaviour of the magnetotransport data is discussed using a model for parallel conduction. 相似文献
995.
An asymmetric line-axis compound parabolic concentrating single basin solar still of concentration 1.15, exit aperture 0.24 metres and length 0.48 metres, 30° inclination and 60° half acceptance angle has been designed fabricated and tested. 相似文献
996.
997.
998.
A. N. Atanov 《Measurement Techniques》1994,37(11):1320-1321
Translated from Izmeritel'naya Tekhnika, No. 11, pp. 66–67, November, 1994. 相似文献
999.
X-ray phase, differential thermal, and metallographic analyses are used to study the reaction of phosphorus with Fe, Co, Ni, and Mn on heating in an inert atmosphere. It is found that low-temperature endo- and exothermic effects are related to formation of Fe3P, Co2P, Ni3P, and Mn3P. The effect of eutectic contact melting on the metal-phosphide interface is observed in all specimens. 相似文献
1000.
V. I. Belousov G. G. Denisov N. Yu. Peskov 《Journal of Infrared, Millimeter and Terahertz Waves》1991,12(9):1035-1043
The article presents results of theoretical and experimental investigation of quasioptical multiplexer based on reflecting diffraction grating. Diffraction losses caused by reflection into mirror harmonic, and by angle divergence of wave beams are calculated. In an experimental multiplexer, wave beams with the frequencies 70 GHz and 79 GHz were mixed with power losses less than 1%. 相似文献