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21.
An American kindred with systemic amyloidosis presenting with carpal tunnel syndrome, peripheral neuropathy, and cardiomyopathy is reported. The transthyretin gene of a patient was analysed by direct DNA sequencing and both cytosine and thymine were present at the first base of codon 24. This new point mutation in exon 2 results in the amino acid substitution of serine for proline in the A-B loop of the transthyretin molecule. DNA testing for this mutant allele by restriction fragment length polymorphism analysis based on the polymerase chain reaction is described. 相似文献
22.
Flow cytometry is a quantitative cytologic technique with demonstrated utility in the assessment of prostate cancer as well as other tumors. The authors summarize current data on its use in disease detection and diagnosis, prognostic evaluation, and monitoring of response to therapy. They also project future developments. 相似文献
23.
M D Benson 《Hospital practice (Office ed.)》1988,23(3):165-72, 177, 181
24.
The knowledge that (1) the normal thyroid contains somatostatin, (2) polypeptide growth factors influence thyroid cell function, and (3) thyroid cells contain steroid hormone receptors prompted us to add somatostatin analogue No. 201-995 (SMS) (5 ng/ml) and/or tamoxifen citrate (TAM) (5 mumol/L) to 7-day monolayer cultures (50,000 cells/well) of three separate human thyroid carcinoma cell lines: DR081 (medullary), WR082 (follicular), and NPA'87 (papillary). Results, tabulated as cell numbers/well (X10(5) on day 7, revealed that TAM inhibited growth of medullary and follicular cells and that TAM plus SMS inhibited growth of papillary cells. In vivo studies of subcutaneous tumor cell xenografts in nude mice have documented that TAM (5 mg subcutaneous pellet) significantly inhibits the growth of medullary implants. Flow cytometric DNA studies of medullary cell cultures demonstrated a reduced G2 + M phase with TAM treatment. For papillary cell implants, TAM plus SMS (5 micrograms subcutaneously, twice daily) did not suppress tumor growth. All three cell lines were negative for estrogen receptor; addition of estradiol (5 ng/ml) to medullary cell cultures neither stimulated replication nor reversed the inhibitory effects of TAM in vitro. We conclude that (1) TAM slowed the growth of a cell line of human medullary carcinoma, both in vitro and in vivo; (2) this effect was not reversed by estradiol; (3) TAM plus SMS inhibited replication of a papillary carcinoma cell line in vitro, but not in vivo; and (4) TAM alone and TAM plus SMS inhibited replication of cultures of a human follicular thyroid carcinoma cell line. TAM and SMS may be useful in treatment of some human thyroid carcinomas. 相似文献
25.
Nonprogression of subclinical beta-cell dysfunction among first-degree relatives of IDDM patients. 5-yr follow-up of the Seattle Family Study 总被引:4,自引:0,他引:4
D K McCulloch L J Klaff S E Kahn S L Schoenfeld C J Greenbaum R S Mauseth E A Benson G T Nepom L Shewey J P Palmer 《Diabetes》1990,39(5):549-556
It is unknown among first-degree relatives of individuals with insulin-dependent diabetes mellitus (IDDM) whether the disease process occurs in relatively few but always progresses to clinical IDDM or whether subclinical disease is more common but remains nonprogressive in many cases. Islet cell antibodies (ICAs) were found in 21 of 724 (2.9%) first-degree relatives during screening in the greater Seattle area between 1983 and 1988. Measures of beta-cell function (glucose disappearance rate [Kg], fasting insulin, acute insulin response to intravenous arginine [AIRarg], acute insulin response to intravenous glucose [AIRgluc], slope of glucose potentiation of AIRarg) and insulin sensitivity were obtained. Twenty individuals, 9 ICA+ relatives and 11 ICA- relatives, were evaluated prospectively. When expressed in relation to the expected AIRgluc based on each subject's sensitivity index, AIRgluc in 18 of 20 relatives fell below 100%, indicating inappropriately low insulin secretion (subclinical beta-cell dysfunction). After a median follow-up of 42 mo, 10 of 11 ICA- relatives remained ICA-. None showed deteriorating beta-cell dysfunction, and none developed diabetes. Five ICA+ relatives showed persistent immunologic positivity. beta-Cell function remained remarkably stable in all except 2 relatives. One was a 15-yr-old boy who developed IDDM shortly after screening and before evaluation of beta-cell function could be carried out. The other was an 18-yr-old monozygotic twin who developed IDDM after 27 mo. Both of these individuals had ICAs of 80 Juvenile Diabetes Foundation U and had been discordant for less than 5 yr.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
26.
Hamid R Djalilian Saswata Roy Aaron G Benson Christopher Regala Timothy B McDonald Tina Leman 《Otology & neurotology》2005,26(4):674-677
OBJECTIVE: Given the associated risk of general anesthesia in elderly patients with cardiovascular disease, the authors set out to determine the feasibility of transcanal cochlear implantation under local anesthesia with monitored anesthesia care. METHODS: A 70-year-old man with a history of coronary artery bypass grafting, diabetes mellitus, and an American Society of Anesthesiologists Class III cardiac status underwent cochlear implantation under local with monitored anesthesia care. RESULT: With the described technique and regimen of intravenous remifentanil and dexmedetomidine, the patient tolerated the 60-minute procedure without tachycardia, hyper- or hypotension, or cardiac ischemia. CONCLUSION: Cochlear implantation using the pericanal electrode technique performed under local anesthesia with monitored anesthesia care is possible in patients at risk for undergoing general anesthesia for cochlear implantation. 相似文献
27.
28.
Stefanie Sarantopoulos Kristen E Stevenson Haesook T Kim Nazmim S Bhuiya Corey S Cutler Robert J Soiffer Joseph H Antin Jerome Ritz 《Clinical cancer research》2007,13(20):6107-6114
PURPOSE: Recent studies suggest that donor B cells as well as T cells contribute to immune pathology in patients with chronic graft-versus-host disease (GVHD). B-cell activating factor (BAFF) promotes survival and differentiation of activated B cells. Thus, we tested whether BAFF correlated with chronic GVHD disease activity and time of onset after allogeneic hematopoietic stem cell transplantation (HSCT). EXPERIMENTAL DESIGN: Patients who had undergone allogeneic HSCT between 1994 and 2005 for hematologic malignancies were studied. ELISA was used to measure plasma BAFF levels and flow cytometry was used to assess BAFF receptor expression on B cells in patients with or without chronic GVHD. RESULTS: In 104 patients, BAFF levels were significantly higher in patients with active chronic GVHD compared with those without disease (P = 0.02 and 0.0004, respectively). Treatment with high-dose prednisone (>or=30 mg/d) was associated with reduced BAFF levels in patients with active chronic GVHD (P = 0.0005). Serial studies in 24 patients showed that BAFF levels were high in the first 3 months after HSCT but subsequently decreased in 13 patients who never developed chronic GVHD. In contrast, BAFF levels remained elevated in 11 patients who developed chronic GVHD. Six-month BAFF levels >or=10 ng/mL were strongly associated with subsequent development of chronic GVHD (P < 0.0001). Following transplant, plasma BAFF levels correlated inversely with BAFF receptor expression on B cells (P = 0.01), suggesting that soluble BAFF affected B cells through this receptor. CONCLUSION: These results suggest that elevated BAFF levels contribute to B-cell activation in patients with active chronic GVHD. 相似文献
29.
The complex enterprise of modelling prenatal exposure to cigarettes: what is ‘enough’? 总被引:1,自引:0,他引:1
Kate E. Pickett Paul J. Rathouz Vanja Dukic Kristen Kasza Marina Niessner Rosalind J. Wright Lauren S. Wakschlag 《Paediatric and perinatal epidemiology》2009,23(2):160-170
While there is a burgeoning body of research linking smoking during pregnancy to problem behaviour in offspring, a major criticism of this work has been the crude measurement of exposure in these studies (e.g. retrospective, self-reported only) that could lead to biased estimates. To address this issue, we used a pregnancy cohort with repeated prospective measures of exposure as well as biological assays to generate estimates of exposure patterns using a range of modelling techniques. In this paper we report on the analytical approaches we have developed, including patterns of exposure over time and best-estimate approaches that combine self-report and cotinine measures, and compare their predictive value in relation to different dimensions of fetal growth as a first step towards examining the utility of greater precision of exposure measurement.
Surprisingly, in this sample the more complex assessments of exposure, including biological measures, generally did not perform better than simple indicators of exposure based on repeated self-report measures, with one exception: a combined self-report cotinine 'best estimate' of third trimester exposure was uniquely associated with lower brain : body ratio. Further study is needed using more sophisticated cotinine assays and testing prediction of a range of outcomes to ascertain whether these findings represent true differences or are specific to the sample, methods and outcomes used. Such research will inform the development of guidelines for adequate exposure characterisation in developmental studies. 相似文献
Surprisingly, in this sample the more complex assessments of exposure, including biological measures, generally did not perform better than simple indicators of exposure based on repeated self-report measures, with one exception: a combined self-report cotinine 'best estimate' of third trimester exposure was uniquely associated with lower brain : body ratio. Further study is needed using more sophisticated cotinine assays and testing prediction of a range of outcomes to ascertain whether these findings represent true differences or are specific to the sample, methods and outcomes used. Such research will inform the development of guidelines for adequate exposure characterisation in developmental studies. 相似文献
30.
Mitch Ricketts James Shanteau Breeanna McSpadden Kristen M. Fernandez-Medina 《Social science & medicine (1982)》2010
After 14 years of rising death rates due to unintentional injuries in the U.S., it is time to ask how safety messages can be redesigned to have a greater impact on risky behavior. To this end, many researchers have called for a new, narrative approach to prevention messages—based on persuasive stories about people who have suffered injuries and illnesses in the past. Still, there is scant evidence that story-based communications are more effective than equivalent non-narrative messages at changing actual (rather than self-reported) safety and health behavior. Our research examined the impact of injury stories on actual safety behavior in a controlled experimental setting at a US university. Teams of participants assembled a product (a child's swing) using written instructions. The instructions contained safety messages targeting assembly mistakes that have been linked to serious injuries in children who play on swings. Participant teams were randomly assigned to three conditions: assembly instructions containing story-based safety messages, instructions with concrete (but non-anecdotal) safety messages, and instructions with traditional abstract safety messages. After adjustment for covariates, story-based messages resulted in a 19 percent improvement in safety behavior, compared with non-narrative communications. Importantly, injury stories did not create undue fear of the message object, demonstrating that brief anecdotes about accident victims can convince people to take reasonable precautions without creating unwarranted alarm about risks. 相似文献