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71.
Holger Hoehn Maria L. Rodriguez Thomas H. Norwood Clare L. Maxwell Uta Francke 《American journal of medical genetics. Part A》1978,2(3):253-266
The last decade has witnessed increasing application of human cytogenetic technology to prenatal chromosome analysis. However, unlike the rather uniform peripheral blood T-lymphocyte system which has provided most of our experience in human cytogenetics, long-term amniotic-fluid cell cultures display extreme cellular heterogeneity and disproportionate growth of certain cell types as a consequence of clonal amplification. When they enter cell culture, many of these cells are approching the terminal stages of their respective life spans and may have accumulated chromosomal aberrations. Concern about the possibility of true fetal mosaicism seems warranted chiefly in situations were multiple colonies display potentially viable aberrations. Clonal analysis, preferable of multiple clonal types, and attention to details of clonal morphology are likely to minimize diagnostic errors and undue apprehension resulting from mosaicism in amniotic-fluid cell cultures. 相似文献
72.
I J Fox L L Perry M S Sy B Benacerraf M I Greene 《Clinical immunology and immunopathology》1980,17(1):141-155
73.
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75.
June A Peters Susan T Vadaparampil Joan Kramer Richard P Moser Lori Jo Peterson Court Jennifer Loud Mark H Greene 《Genetics in medicine》2006,8(12):760-770
PURPOSE: This study is part of an ongoing National Cancer Institute multidisciplinary, etiologically-focused, cross-sectional study of Familial Testicular Cancer (FTC). The current report targets interest in clinical genetic testing for susceptibility to FTC. METHODS: Demographics, knowledge, health beliefs, and psychological and social factors were evaluated as covariates related to interest in genetic testing. RESULTS: The majority (66%) of 229 participants (64 affected men, 66 unaffected men, and 99 women) from 47 multiple-case FTC families expressed interest in having a genetic test within 6 months, should such a test become available. Interest was similar among the three subgroups mentioned above. Worries about insurance discrimination based on genetic test results were associated with a significantly lower interest in testing. Alternatively, participants were more likely to be interested in genetic testing if they were younger and had higher levels of family support, a physician's recommendation supporting testing, cancer distress, and a need for information to inform the health care of their children. CONCLUSIONS: This study reveals social and relationship factors that FTC survivors and their relatives considered important when contemplating the use of new genetic technologies. This is the first study describing hypothetical interest in genetic testing for familial testicular cancer. 相似文献
76.
Stereoselectivity of L-baclofen in hippocampal slices of the rat 总被引:2,自引:0,他引:2
Extra- and intracellular recording from hippocampal slices of the rat revealed the following effects when baclofen (BF) (0.1-10 microM) was added to the perfusion fluid: a block of synaptic potentials evoked by stimulation of stratum radiatum; a direct hyperpolarization and a conductance increase (for potassium ions) of CA1 pyramidal cells. All this activity was found in the L- none in the D-enantiomer. D-BF did not antagonize the action of L-BF. 相似文献
77.
The c-erbB-2 oncogene encodes a transmembrane phosphoglycoprotein. This molecule appears to be a growth factor receptor in the family of tyrosine kinase growth factor receptors; however, its ligand has not yet been identified. Amplification and/or overexpression of c-erbB-2 in breast adenocarcinomas occurs frequently and its occurrence implies a more advanced malignancy. This functional tumor marker is readily identified by appropriate DNA and antibody probes. The large external domain of the c-erbB-2 gene product is a promising target for immunodiagnostic and immunotherapeutic modalities. 相似文献
78.
R E Galinsky D Eshima L Hansen J Greene D Dillehay A Taylor 《Mechanisms of ageing and development》1990,56(3):209-222
The effect of aging on glomerular filtration, effective renal plasma flow and on the responsiveness of the renal tubular anion secretory system to inhibition by 4-aminobenzoylglycine (p-aminohippurate, PAH) was examined in young (5-month) and old (22-month) Fischer 344 male rats. Plasma clearance, protein binding and renal extraction of [131I]o-iodohippurate, [125I]iothalamate and HPLC-purified [99mTc]mercaptoacetyltriglycine (MAG3), were used as in vivo probes of renal function. The effect of advanced age, without concomitant PAH, on the disposition of these markers was initially determined in ketamine anesthetized, temperature-maintained male rats, ages 5, 14 and 22 months by means of constant infusion clearance studies. Aging per se decreased (P less than 0.05) the kidney-weight normalized or body weight-normalized GFR and effective renal plasma flow rates. GFR values averaged 1.67, 1.43 and 1.32 ml/min per g kidney for the 5-, 14- and 22-month-old rats, respectively. Kidney- or body weight-normalized clearances of MAG3 and o-iodohippurate showed similar (25-27%) decreases, whereas the absolute values (ml/min) for GFR, o-iodohippurate and MAG3 clearance rates were not altered by aging. The effective filtration fraction, extraction ratio and plasma protein binding were also unchanged by advanced age. Overall, the age-related decreases in renal function were minimal in Fischer-344 rats, compared to other species. Differences in data normalization, species and gender account, in part, for discrepancies observed when comparing results in different studies on the effects of advanced age on renal function. Subsequently, we examined the effect of aging on the renal responsiveness to inhibition of tubular anion secretion using constant rate PAH infusion studies, adjusted for age-related changes in renal function. Aging did not alter PAH-induced inhibition of iodohippurate secretion. Inhibition of MAG3 elimination was more pronounced in the old rats compared to the young controls. 相似文献
79.
Ushma D. Upadhyay Phoebe Y. Danza Torsten B. Neilands Jessica D. Gipson Claire D. Brindis Michelle J. Hindin Diana Greene Foster Shari L. Dworkin 《The Journal of adolescent health》2021,68(1):86-94
PurposeWe developed and validated a measure that assesses the latent construct of sexual and reproductive empowerment among adolescents and young adults. A specific measure for this group is critical because of their unique life stage and circumstances, which often includes frequent changes in sexual partners and involvement from parents in decision-making.MethodsAfter formative qualitative research, a review of the literature, and cognitive interviews, we developed 95 items representing nine dimensions of sexual and reproductive empowerment. Items were then fielded among a national sample of young people aged 15–24 years, and those who identified as sexually active completed a 3-month follow-up survey. We conducted psychometric analysis and scale validation.ResultsExploratory factor analysis on responses from 1,117 participants resulted in the Sexual and Reproductive Empowerment Scale for Adolescents and Young Adults, containing 23 items captured by seven subscales: comfort talking with partner; choice of partners, marriage, and children; parental support; sexual safety; self-love; sense of future; and sexual pleasure. Validation using logistic regression demonstrated that the subscales were consistently associated with sexual and reproductive health information and access to sexual and reproductive health services measured at baseline and moderately associated with the use of desired contraceptive methods at 3-month follow-up.ConclusionsThe Sexual and Reproductive Empowerment Scale for Adolescents and Young Adults is a new measure that assesses young people’s empowerment regarding sexual and reproductive health. It can be used by researchers, public health practitioners, and clinicians to measure sexual and reproductive empowerment among young people. 相似文献
80.
Michael J. DeFrance Michael F. Yayac P. Maxwell Courtney Matthew W. Squire 《The Journal of arthroplasty》2021,36(4):1462-1469
BackgroundRecent studies have suggested clinical superiority with robotic-assisted arthroplasty compared to traditional techniques. However, concerns exist regarding the author’s financial conflicts of interest (COI), which may influence research outcomes. This study aimed to determine whether COI relating to robotic-assisted arthroplasty influences the results of published outcomes following total hip (THA), total knee (TKA), and unicompartmental knee arthroplasty (UKA).MethodsWe performed a systematic review to identify all studies evaluating the use of robotics in THA, TKA, and UKA. An author’s financial COI was identified if they reported a relevant disclosure through the American Academy of Orthopedic Surgeons or within the study article. We then queried the Open Payments website to record all payments made from a robotic company in the year prior to publication. Each study was categorized as either favoring robotics (n = 42), neutral (n = 10), or favoring traditional techniques (n = 2). We then compared the number of conflicted authors, journal impact factor, level of evidence, and mean annual industry payment to each author.ResultsOf the 54 studies meeting inclusion criteria, 49 (91%) had an author financial COI. Conflicted studies were more likely to report favorable results of robotics than nonconflicted studies. When compared to studies favoring conventional techniques, those demonstrating favorable robotics outcomes had a higher number of conflicted authors and a higher mean industry payment per author. There was no difference in the level of evidence or journal impact factor.DiscussionNearly all studies comparing robotic THA, TKA, and UKA to conventional techniques involve financially conflicted authors. Further studies without COI may provide unbiased results. 相似文献