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31.
Graham Fuller Murphy Jones Forman & Swerdlow 《Paediatric and perinatal epidemiology》1999,13(3):316-324
This study examined the association between numbers of benign melanocytic naevi in 7-year-old children in Oxfordshire born in 1988-9 with their mother's arm naevus count, and maternal and child pigmentation factors. We believe this is the first time that the relationship between child and maternal naevus counts has been reported. A high naevus count in the child was associated with male sex (P = 0.009), freckling (P = 0.001) and propensity of the child to burn in the sun (P = 0.05). A low naevus count was observed in red-haired children (P = 0.02). The strongest association of child's naevus count was with a high maternal arm naevus count, independent of the child's pigmentation factors (trend P < 0.0001). Maternal pigmentation factors were not associated with child's naevus count independent of the child's own pigmentation factors. Maternal arm naevus counts may be a better predictor of child naevus count than the child's own pigmentation factors and children. There has not been examination, however, of the relationship between naevus counts in children and those in their parents. We therefore conducted a study of the occurrence of naevi in children aged 7-8 years in Oxfordshire, examining, in addition to sex and pigmentation factors in the child, the relationship of maternal pigmentation factors and maternal naevus counts with naevi in their offspring. 相似文献
32.
Honn KV Aref A Chen YQ Cher ML Crissman JD Forman JD Gao X Grignon D Hussain M Porter AT Pontes JE Powell I Redman B Sakr W Severson R Tang DG Wood DP 《Pathology oncology research : POR》1996,2(1-2):98-109
Rates of prostate cancer (PCa) have increased so dramatically over the last decade that the age adjusted incidence rate for PCa is now greater than that any other cancer among men in the United States. This review, published as a three part series, provides a state-of-art assessment of the PCa problem in its divergent aspects.Part 1 covers epidemiology, incidence and progression. Several epidemiological studies have demostrated that first degree male relatives of men with PCa are at increased risk of developing the disease. Familial and genetic factors as well as medical, anthropometric, dietary, hormonal and occupational factors involved in PCa are discussed. Postmortem examination of the prostate in men without evidence of PCa documented a high frequency of adenocarcinoma. Latent disease occurred as early as the second decade of life. Although there is no significant difference in incidence between Caucasian and African-American males, high grade prostatic intraepithelial neoplasia (HGPIN) is higher in the latter group. While dietary fat, androgens and certain environmental factors may be determinants for PCa, the exact mechanism of tumorigenesis is still relatively unknown. The current thinking of the role of genomic instability, chromosomal alterations, tumor suppressor genes and the androgen receptor are explored. 相似文献
33.
Two children presented with Ph1-positive leukemia, confirmed by Giemsa banding as 22q-. One child showed an initial presentation characteristic of acute lymphoblastic leukemia, followed by development of chronic myelocytic leukemia 2 yr later. A second child presented in blast crisis. Both patients showed blast cells possessing both lymphoid and myeloid characteristics, as demonstrated by histochemical, biochemical, or surface receptor properties of each cell series. The evidence provided supports the assumption of mixed lymphoid-myeloid properties of blast cells in chronic myelocytic leukemia in children. Detailed study of the leukemic cells may aid in the understanding of complex stem cell relationships and suggest more effective therapeutic approaches. 相似文献
34.
Circadian rhythms in Neurospora crassa: a mutation affecting temperature compensation. 总被引:3,自引:1,他引:2
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D L Mattern L R Forman S Brody 《Proceedings of the National Academy of Sciences of the United States of America》1982,79(3):825-829
The circadian rhythm of conidiation (spore formation) in Neurospora crassa is known to be temperature compensated, that is, the period is only slightly affected by the incubation temperature. Thus, the Q10 (the relative rate enhancement corresponding to a 10 degrees C rise in temperature) of the rhythm of the bd csp strain from 14 to 30 degrees C was 1.1, whereas the Q10 of the uncompensated growth rate in the same interval was 2.4. A mutation at the cel locus resulted in loss of the temperature-compensation property in cultures grown below 22 degrees C. The Q10 of the rhythm below 22 degrees C was 2.2, and periods of about 40 hr were observed. In contrast, the Q10 of the rhythm above 22 degrees C was 1.1, with circadian periods of 18-21 hr. Thus, cel displayed a threshold temperature or "break point" for the temperature compensation of its rhythm. Supplementation of cel strains, which require fatty acids, with unsaturated or short-chain fatty acids raised the threshold temperature to 26 degrees C, whereas supplementation with long-chain saturated fatty acids lowered it to 18 degrees C. These data suggest a role for fatty acids, as liquid components or as cellular metabolites, in the mechanism of temperature compensation. 相似文献
35.
36.
OBJECTIVE. The purpose of this article is to report 1999 data on the job market in diagnostic radiology detected using a help wanted index of job advertisements and to profile trends in practice type, location, and subspecialty using our previously published data as a basis for comparison. MATERIALS AND METHODS. Each advertised job for a diagnostic radiologist in the American Journal of Roentgenology and RADIOLOGY: between January 1991 and December 1999 was coded by practice type, location, and subspecialty. RESULTS. In 1999, 3926 positions were advertised for diagnostic radiologists, representing a 75% increase from 1998. Private practice jobs, which represented 53% of advertisements from 1991 through 1994 and 64% of ads from 1995 through 1998, increased to 66% of ads in 1999. Geographic trends in 1999 were characterized by a relative increase of jobs in the Midwest and California and a decrease in percentage (but increase in total number of ads) in the Northeast and Southwest. The demand for subspecialists continued in 1999, with only 34% of ads placed for general radiologists. A relative increase in demand for neuroradiologists, mammographers, and abdominal imagers was also seen in 1999 in comparison with previously published data from 1995 through 1998. CONCLUSION. The demand for diagnostic radiologists continues to rise, with more ads placed in 1999 than any other year from 1991 through 1998. Using a help wanted index of job advertisements, we have created an indicator of changes in the diagnostic radiology job market with specific reference to practice type, geographic location, and subspecialty training. 相似文献
37.
38.
Lori-Ann Tuscan James D. Herbert Evan M. Forman Adrienne S. Juarascio Meltem Izzetoglu Maria Schultheis 《Brain imaging and behavior》2013,7(2):140-153
Preliminary studies examining brain function associated with social anxiety suggest the possibility of right-sided prefrontal activation associated with phobic stimulation. Although most existing neuroimaging techniques preclude participants from engaging in ecologically valid social tasks during assessment, functional near-infrared spectroscopy (fNIRS) is a promising new technique that permits such assessment. The present study investigated the utility of the fNIRS procedure and explored frontal asymmetry during in vivo social challenge tasks among female undergraduate students who scored in top and bottom percentiles on a social anxiety screening measure. Results revealed that participants in both groups experienced a significant increase in concentration of blood volume and oxygenated hemoglobin in the right hemisphere compared to the left hemisphere while giving a speech. Non-hemispheric effects were also observed. In addition, the high anxiety group showed a non-significant trend toward greater right frontal activity than the low anxiety group. This study highlights the utility of the fNIRS device in successfully assessing real-time changes in cerebrovascular response as a function of naturalistic social behavior, and supports the potential utility of this technology in the study of the neurophysiology of social anxiety. 相似文献
39.
In oocyte donation cycles where hormone replacement is given to recipients, progesterone administration is necessary to induce the luteal phase and synchronize the endometrium with the embryo stage. Most studies suggest that 5–7 days of progesterone are needed to prepare the endometrium for a day-5 embryo transfer and provide optimal implantation rate. This paper reports a case where an agonadal oocyte recipient received only 2 days of progesterone prior to the embryo transfer of a day-5 embryo. She subsequently had a clinical pregnancy and a live birth. 相似文献
40.
Factors that affect implementation of a nurse staffing directive: results from a qualitative multi‐case evaluation
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