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1.
Dr. Barry Pass John E. Aldrich Patricia L. Scallion 《Calcified tissue international》1990,46(3):166-168
Summary The ESR spectra produced in irradiated dentin have been studied over a range of incident radiation energies from 50 kVp to
25 MVp. The behavior of the dentin ESR signal strength is similar to that of enamel as a function of the energy of the incident
radiation. The magnitude of the dentin ESR signals are, however, up to 10 times smaller than the signals of dental enamel
for a given radiation energy. The possible contributions of radiation interaction coefficients, chemical structure, and crystallite
size to the differences in ESR spectra are discussed. 相似文献
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3.
J E Aldrich 《Journal l'Association canadienne des radiologistes》1988,39(2):137-139
Many hospitals are faced with the development of radiation emergency plans. Details are given of the relevant literature and audio-visual materials to assist in the development of such a plan. 相似文献
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6.
End-of-life (EOL) and palliative care education in medical school curricula stand at a crossroads. Consensus has emerged that these topics merit systematic instruction throughout medical school training, yet curricula all too often consist of sporadic lectures focused on bioethics instead of clinical skills. The medical student authors identified a deficit in their curriculum, and designed and implemented an EOL curriculum module for their colleagues. In early 2000 the authors surveyed senior medical students about their experiences with EOL and palliative education, identifying deficits in clinical training and recommendations for interventions. They then designed a case-based educational module to teach EOL communication skills to medical students commencing clinical training. Faculty with national and local experience with EOL and palliative care reviewed the curriculum. Twelve of these faculty were oriented to the curriculum and then taught it in pairs to groups of 12 to 16 medical students in 2000 and 2001. The curriculum develops skills, attitudes, and knowledge relevant for communicating bad news and establishing treatment options in the EOL setting by utilizing trigger videos, group discussion, role plays, and case discussions. Approximately 75% of the 86 eligible students attended the module in 2000 and 2001. Feedback has guided the curriculum's refinement by the medical student authors. In addition, a standardized patient exercise, introduced in 2001, allowed students to reinforce the skills learned during the module. 相似文献
7.
Alterations in the genomes of avian sarcoma viruses 总被引:3,自引:0,他引:3
W S Mason M Linial T W Hsu R N Eisenman J Townsend G E Mark G Seal C Aldrich J M Taylor 《Virology》1982,117(2):456-474
We have identified polypeptides specific to region Elb (map position [mp] 4.6–112) of adenovirus 2 (Ad2) that are synthesized in six lines of Ad-transformed rat or human cells (F17, F4, T2C4, 8617, 5RK clone I, 293), and in Ad2 early infected KB cells. [35S]Methionine-labeled polypeptides were immunoprecipitated using antisera against F17 cells, an Ad2-transformed rat cell line that retains only El. To determine whether they are viral coded, these polypeptides were compared by tryptic peptide mapping with polypeptides translated in vitro from Ela-specific mRNA (mp 1.3–4.5) and Elb-specific mRNA. Polypeptides of 19,000 daltons early infected KB cells. The 19K, 20K, and 53K could be translated from Elb-specific mRNA and thus are coded by Elb. The 19K was precipitated from all transformed cell lines, the 20K was immunoprecipitated from F4, 8617, and T2C4 cells, and the 53K was immunoprecipitated from F4, 8617, T2C4, and 293 cells. These results suggest that the 19K, and perhaps the 20K and 53K, may be important in adenovirus-induced cell transformation. The 20K and 53K share methionine-containing tryptic peptides with each other, but not with the 19K. These results, together with the Ad2 Elb DNA sequence (T. Gingeras and R. Roberts, personal communication), suggest that 19K is translated in a different reading frame from 53K and 20K. 相似文献
8.
Neulen J; Raczek S; Pogorzelski M; Grunwald K; Yeo TK; Dvorak HF; Weich HA; Breckwoldt M 《Molecular human reproduction》1998,4(3):203-206
Vascularization is a prominent event during corpus luteum formation,
providing low density lipoproteins for steroid biosynthesis and enabling
transport of secreted steroids. The process of vascularization is
controlled by specific regulators. Vascular endothelial growth factor
(VEGF), otherwise named vascular permeability factor (VPF), induces
endothelial cell proliferation as well as angiogenesis in vivo and
increases capillary permeability. Here we report the expression of VEGF/VPF
mRNA by cultured human luteinized granulosa cells (GC) for at least 10
days. Without HCG VEGF/VPF expression declined after day 4 and by day 10
was reduced to approximately 30% of the value at day 4. However, after
culture in the presence of 1 U/ml human chorionic gonadotrophin (HCG),
expression of VEGF/VPF mRNA by GC was four times greater than control
experiments by day 10, and increased 100% from day 4 to day 10.
Simultaneously, HCG supplementation increased VEGF/VPF secretion by GC.
Medium VEGF/VPF on day 3 was 13 pM without and 11 pM with HCG. Medium
VEGF/VPF on day 10 was 6 pM without HCG and 29 pM with HCG. These results
suggest that vascularization of the corpus luteum is induced by
HCG-mediated effects of VEGF/VPF.
相似文献
9.
Experimental transmission of duck hepatitis B virus 总被引:22,自引:0,他引:22
W S Mason M S Halpern J M England G Seal J Egan L Coates C Aldrich J Summers 《Virology》1983,131(2):375-384
10.
This work describes our experience in reviewing the performance criteria for display systems and how we have implemented a
practical approach to the assessment of the workstation environment in a large tertiary care hospital. The acceptance criteria
contained in the draft report of Topic Group 18 of the American Association of Physicists in Medicine (AAPM) were used as
a basis for assessment of primary and secondary displays. A telescopic photometer was used to measure the maximum luminance
and the contrast ratio of the image for the displays used in our radiology department and in the operating and emergency rooms
using the standard Society of Motion Picture and Television Engineers (SMPTE) pattern, in ambient light and with light decreased
as much as possible. About half of the displays met the AAPM criteria for minimum luminance and contrast ratio in low light.
None of the systems met the contrast ratio criteria in ambient light. The challenges in improving the performance and calibrating
displays are discussed. 相似文献