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81.
PL Grimaldi 《Canadian Metallurgical Quarterly》1998,29(11):10-12
Prospective payment systems are replacing the methods Medicare uses to reimburse home health agencies, skilled nursing facilities, and rehabilitation hospitals, as well as imposing new limits on payments for outpatient rehabilitation services. Medicare stands to save substantial sums of money and possibly to hasten the formation of integrated delivery systems for postacute care. 相似文献
82.
PL Ivanov 《Canadian Metallurgical Quarterly》1998,41(4):30-47
The paper presents the results of international complex molecular genetic expert identification of skeletal remains of 9 subjects buried near the Koptiaki road in Ekaterinburg region, presumably belonging to the Romanov Royal Family and persons in their attendance. The armory of methods based on analysis of the least permissible amounts of DNA by the polymerase chain reaction and direct fluorescent sequencing of amplified DNA fragments included the latest scientific technologies. In addition, new methods were developed and used, which have no analogs in the world expert practice. The strategy included identification of biological gender of skeletons, of familial group among exhumed individuals, and of ties of relationship of this family with two independent maternal branches of the Romanov genealogical tree using tracing kindred markers based on mitochondrial DNA (mtDNA). The study was carried out in two stages: in 1992-1993 at Aldermaston Criminology Center of Home Office of the UK with participation of British specialists and in 1995 at Military Medical Institute of Ministry of Defence of the USA in Washington with participation of American specialists. In 1993 five skeletons were identified as Emperor Nicholas II, Empress Alexandra Fedorovna, and their three daughters with 99.6% certainty. From modern criminological viewpoint, the result could not be considered as sufficiently certain for such an extraordinary case, and therefore in 1995 molecular genetic studies of presumable remains of Nicholas II and his brother Prince Georgi? Romanov were carried out again. The results showed absolute positional identity of mtDNA genetic code of these two men due to an extremely rare genetic abnormality (heteroplasmia), and thus the problem of appurtenance of the remains to the Romanov royal family was solved. 相似文献
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M Dubuc M Talajic D Roy B Thibault TK Leung PL Friedman 《Canadian Metallurgical Quarterly》1998,2(3):285-292
BACKGROUND AND PURPOSE: Accurate contouring of the clinical target volume (CTV) is a fundamental prerequisite for successful conformal radiotherapy of prostate cancer. The purpose of this study was to investigate intra- and inter-observer variability in contouring prostate (P) and seminal vesicles (SV) and its impact on conformal treatment planning in our working conditions. MATERIALS AND METHODS: Inter-observer variability was investigated by asking five well-trained radiotherapists of contouring on CT images the P and the SV of six supine-positioned patients previously treated with conformal techniques. Short-term intra-observer variability was assessed by asking the radiotherapists to contour the P and SV of one patient for a second time, just after the first contouring. The differences among the inserted volumes were considered for both intra- and inter-observer variability. Regarding intra-observer variability, the differences between the two inserted contours were estimated by taking the relative differences in correspondence to the CT slices on BEV plots (antero-posterior and left-right beams). Concerning inter-observer variability, the distances between the internal and external envelopes of the inserted contours (named projected diagnostic uncertainties or PDUs) and the distances from the mean inserted contours (named mean contour distances or MCDs) were measured from BEV plots (i.e. parallel to the CT slices). RESULTS: Intra-observer variability was relatively small (the average percentage variation of the volume was approximately 5%; SD of the differences measured on BEV plots within 1.8 mm). Concerning inter-observer variability, the percentage SD of the inserted volumes ranged from 10 to 18%. Differences equal to 1 cm in the cranio-caudal extension of P + SV were found in four out of six patients. The largest inter-observer variability was found when considering the anterior margin in the left-right beam of P top (MCD = 7.1 mm, 1 SD). Relatively high values for MCDs were also found for P bottom, for the posterior and lateral margins of P top (2.6 and 3.1 mm, respectively, I SD) and for the anterior margin of SV (2.8 mm, 1 SD). Relatively small values were found for P central (from 1.4 to 2.0 mm, 1 SD) and the posterior margin of SV (1.5 mm, 1 SD). CONCLUSIONS: The application of larger margins taking inter-observer variability into account should be taken into consideration for the anterior and the lateral margins of SV and P top and for the lateral margin of P. The impact of short-term intra-observer variability does not seem to be relevant. 相似文献
85.
JA Hejna PL Johnstone SL Kohler DA Bruun CA Reifsteck SB Olson RE Moses 《Canadian Metallurgical Quarterly》1998,26(4):1124-1125
Bacterial Artificial Chromosomes (BACs) have been used to complement a metabolic defect and to transfer a drug resistance marker into mammalian cells by electroporation. The selectable markers are stable and the recipient cells have BAC DNA integrated into the chromosomes as shown by fluorescent in situ hybridization, PCR and Southern hybridization. 相似文献
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Inheritance of a major susceptibility gene for breast cancer has been primarily investigated in families with early-onset disease. However, familial clustering of late-onset breast cancer is well documented, and genetic factors may also be relevant. In the Iowa Women's Health Study, we evaluated evidence for a major gene after allowing for measured environmental risk factors. Two hundred sixty-five incident breast cancer probands were identified from a prospective cohort study of 41,837 women aged 55 to 69 years at baseline in 1986. A pedigree development form was mailed to the probands to ascertain all first-degree female relatives. A questionnaire and body measurement protocol were mailed to identified living relatives or surrogates. Segregation analyses were conducted on a total of 1,145 women in 251 families using regressive models as implemented in S.A.G.E. Mendelian codominant inheritance of an allele that produced an earlier-age-at-onset provided the best fit to the data. Incorporation of measured environmental risk factors as covariates yielded no significant improvements in the likelihoods. Approximately 50% of this population could be expected to carry a late-onset breast cancer susceptibility gene, and 23% of the population is susceptible because of the environment in which they live. Homozygous gene carriers are predicted to have a mean age-at-onset of 48 years, over 20 years earlier than heterozygotes; few cases would be expected among non-gene carriers. In conclusion, the transmission pattern of late-onset breast cancer may be determined by a common susceptibility gene. 相似文献
88.
J Tonkiss JS Shumsky PL Shultz SS Almeida JR Galler 《Canadian Metallurgical Quarterly》1995,17(5):601-608
The separate and combined effects of prenatal cocaine exposure and malnutrition on mother-pup interactions in rats were assessed daily from postnatal day 2 to day 21. Sprague-Dawley dams were fed a diet of low protein content (6% casein), an isocaloric diet of adequate protein content (25% casein, control), or a laboratory chow diet prior to mating and throughout pregnancy. Within each diet group, rats received either cocaine injections (30 mg/kg IP two times per week prior to mating and then 30 mg/kg SC daily from days 3 to 18 of pregnancy) or saline injections. Litters were fostered on the day of birth to control mothers (i.e., nondrug-exposed dams fed the control or chow diet). Foster mothers fed the 25% casein diet showed increased contact with cocaine-exposed pups compared with nondrug-exposed pups in the second postnatal week but lower levels as the pups approached weaning. Passive nursing was increased in dams caring for prenatally malnourished, cocaine-exposed pups compared with those caring for similar pups with no drug exposure. Chow-fed mothers did not differ in their behavior towards pups with or without prenatal cocaine treatment. Prenatal cocaine and malnutrition independently compromised birth weight and various reflexive milestones but the attainment of physical milestones was affected only by prenatal cocaine. There were no additive effects of the two prenatal insults on any measure of mother-pup interaction or pup development. 相似文献
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