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991.
Caridi JG West JH Stavropoulos SW Hawkins IF 《AJR. American journal of roentgenology》2000,174(2):363-366
OBJECTIVE: The necessity of obtaining a postprocedure chest radiograph after central venous access using the upper extremity or internal jugular veins and interventional radiologic techniques was evaluated. SUBJECTS AND METHODS: A prospective study of 937 consecutive central venous access procedures in interventional radiology using the internal jugular veins or upper extremities was performed from June 1995 through September 1997. Established interventional radiologic techniques were used to place various ports (n = 34) and tunneled (n = 670) and nontunneled (n = 233) catheters. All catheters were positioned using fluoroscopy and readjusted if necessary before termination of the procedure. Afterward, a chest radiograph was obtained with the patient upright to evaluate catheter position and possible procedural complications. Procedural complications and manipulations or interventions that resulted from the radiographic findings were noted. In addition, nursing time for acquisition of the chest radiograph was recorded. RESULTS: We found seven procedural complications (four air emboli, two pneumothoraces, one innominate vein laceration) significant enough to alter the patient's treatment. These complications were apparent during the examination. Postprocedure chest radiography failed to reveal any unknown complications and revealed only one catheter sufficiently malpositioned to require manipulation. The amount of nursing time to acquire postprocedure chest radiographs ranged from 8 to 40 min (mean, 23 min) per patient. CONCLUSION: When imaging guidance and interventional radiologic techniques are used for upper extremity and internal jugular central venous access, performing postprocedure chest radiography yields little benefit. 相似文献
992.
993.
Howard M Schachter Vasil Mamaladze Gabriela Lewin Ian D Graham Melissa Brouwers Margaret Sampson Andra Morrison Li Zhang Peter O'Blenis Chantelle Garritty 《BMC cancer》2006,6(1):291
Background
Breast cancer in women is increasingly frequent, and care is complex, onerous and expensive, all of which lend urgency to improvements in care. Quality measurement is essential to monitor effectiveness and to guide improvements in healthcare. 相似文献994.
The AIB1 polyglutamine repeat does not modify breast cancer risk in BRCA1 and BRCA2 mutation carriers. 总被引:2,自引:0,他引:2
Amanda B Spurdle Antonis C Antoniou Livia Kelemen Helene Holland Susan Peock Margaret R Cook Paula L Smith Mark H Greene Jacques Simard Marie Plourde Melissa C Southey Andrew K Godwin Jeanne Beck Alexander Miron Mary B Daly Regina M Santella John L Hopper Esther M John Irene L Andrulis Francine Durocher Jeffery P Struewing Douglas F Easton Georgia Chenevix-Trench 《Cancer epidemiology, biomarkers & prevention》2006,15(1):76-79
This is by far the largest study of its kind to date, and further suggests that AIB1 does not play a substantial role in modifying the phenotype of BRCA1 and BRCA2 carriers. The AIB1 gene encodes the AIB1/SRC-3 steroid hormone receptor coactivator, and amplification of the gene and/or protein occurs in breast and ovarian tumors. A CAG/CAA repeat length polymorphism encodes a stretch of 17 to 29 glutamines in the HR-interacting carboxyl-terminal region of the protein which is somatically unstable in tumor tissues and cell lines. There is conflicting evidence regarding the role of this polymorphism as a modifier of breast cancer risk in BRCA1 and BRCA2 carriers. To further evaluate the evidence for an association between AIB1 glutamine repeat length and breast cancer risk in BRCA1 and BRCA2 mutation carriers, we have genotyped this polymorphism in 1,090 BRCA1 and 661 BRCA2 mutation carriers from Australia, Europe, and North America. There was no evidence for an increased risk associated with AIB1 glutamine repeat length. Given the large sample size, with more than adequate power to detect previously reported effects, we conclude that the AIB1 glutamine repeat does not substantially modify risk of breast cancer in BRCA1 and BRCA2 mutation carriers. 相似文献
995.
Ovarian hyperandrogenism in adult female rhesus monkeys exposed to prenatal androgen excess. 总被引:7,自引:0,他引:7
Joel R Eisner Melissa A Barnett Daniel A Dumesic David H Abbott 《Fertility and sterility》2002,77(1):167-172
OBJECTIVE: To determine whether there is an ovarian thecal cell component to hyperandrogenism exhibited in adult female rhesus monkeys exposed to androgen excess during prenatal life. DESIGN: Prospective nonrandomized study. SETTING: An academic research environment. ANIMAL(S): Eleven adult female rhesus monkeys. INTERVENTION(S): Five female rhesus monkeys exposed prenatally to T propionate and six normal females underwent blood sampling immediately before and 24 h after a 200-IU IM injection of recombinant hCG. MAIN OUTCOME MEASURE(S): Serum T, 17alpha-hydroxyprogesterone, DHEAS, and cortisol concentrations determined by RIA. RESULT(S): Prenatally androgenized females exhibited increased T and 17alpha-hydroxyprogesterone response to recombinant hCG stimulation, compared to control females. Although serum adrenal DHEAS concentrations were elevated in comparison to control females, the increased levels of DHEAS were not dependent on recombinant hCG stimulation. CONCLUSION(S): Prenatal androgen excess in female rhesus monkeys causes perturbations in ovarian and adrenal steroidogenesis during adulthood, which may both contribute to hyperandrogenism. 相似文献
996.
997.
Immunohistochemistry versus microsatellite instability testing in phenotyping colorectal tumors. 总被引:31,自引:0,他引:31
Noralane M Lindor Lawrence J Burgart Olga Leontovich Richard M Goldberg Julie M Cunningham Daniel J Sargent Catherine Walsh-Vockley Gloria M Petersen Michael D Walsh Barbara A Leggett Joanne P Young Melissa A Barker Jeremy R Jass John Hopper Steve Gallinger Bharati Bapat Mark Redston Stephen N Thibodeau 《Journal of clinical oncology》2002,20(4):1043-1048
PURPOSE: To compare microsatellite instability (MSI) testing with immunohistochemical (IHC) detection of hMLH1 and hMSH2 in colorectal cancer. PATIENTS AND METHODS: Colorectal cancers from 1,144 patients were assessed for DNA mismatch repair deficiency by two methods: MSI testing and IHC detection of hMLH1 and hMSH2 gene products. High-frequency MSI (MSI-H) was defined as more than 30% instability of at least five markers; low-level MSI (MSI-L) was defined as 1% to 29% of loci unstable. RESULTS: Of 1,144 tumors tested, 818 showed intact expression of hMLH1 and hMSH2. Of these, 680 were microsatellite stable (MSS), 27 were MSI-H, and 111 were MSI-L. In all, 228 tumors showed absence of hMLH1 expression and 98 showed absence of hMSH2 expression: all were MSI-H. CONCLUSION: IHC in colorectal tumors for protein products hMLH1 and hMSH2 provides a rapid, cost-effective, sensitive (92.3%), and extremely specific (100%) method for screening for DNA mismatch repair defects. The predictive value of normal IHC for an MSS/MSI-L phenotype was 96.7%, and the predictive value of abnormal IHC was 100% for an MSI-H phenotype. Testing strategies must take into account acceptability of missing some cases of MSI-H tumors if only IHC is performed. 相似文献
998.
Impact of prolonged infusions of the putative differentiating agent sodium phenylbutyrate on myelodysplastic syndromes and acute myeloid leukemia. 总被引:14,自引:0,他引:14
Steven D Gore Li-Jun Weng William D Figg Suoping Zhai Ross C Donehower George Dover Michael R Grever Constance Griffin Louise B Grochow Anita Hawkins Kathleen Burks Yelena Zabelena Carole B Miller 《Clinical cancer research》2002,8(4):963-970
The aromatic fatty acid sodium phenylbutyrate (PB) promotes cytostasis and differentiation in a wide variety of tumor types; among several molecular activities, inhibition of histone deacetylase (HDAC) may account for many of its pharmacodynamic effects. A Phase I study demonstrated promising preliminary evidence of clinical activity in acute myeloid leukemia and myelodysplastic syndrome; however, plasma concentrations achieved at the maximum tolerated dose were less than those targeted based on in vitro studies. Because prolonged exposure to suboptimal concentrations of PB in vitro led to pharmacodynamic changes similar to a more brief exposure to higher concentrations, a study of the feasibility of prolonged administration of sodium PB was performed. Selected patients with acute myeloid leukemia and myelodysplastic syndrome were treated with sodium PB as a continuous i.v. infusion via ambulatory infusion pump. Sequential cohorts were treated for 7 consecutive days out of 14 or with 21 consecutive days out of 28. Prolonged infusions were well tolerated; dose-limiting central nervous system toxicity developed in 1 of 23 patients treated. End-of-infusion plasma concentrations were maintained within a range sufficient to inhibit HDAC. Two patients on the 21/28 schedule developed hematological improvement. Prolonged infusions of PB are well tolerated making this an attractive platform for the clinical investigation of HDAC inhibition. 相似文献
999.
Sara Chau Melissa Chin Jeannie Chang Ann Luecha Eric Cheng Jennifer Schlesinger Veena Rao David Huang Annette E Maxwell Richard Usatine Roshan Bastani Lillian Gelberg 《Cancer epidemiology, biomarkers & prevention》2002,11(5):431-438
The homeless encounter many barriers to health care and preventive services, while having an increased prevalence of most risk factors for cancer. A group of homeless adults (221) at nine different locations within Los Angeles County were surveyed during the summers of 1998 and 1999. A portion (71%) reported that they had had at least one rectal exam, 42% had a fecal occult blood test, 24% had a skin exam, and 23% had an endoscopy (flexible sigmoidoscopy or colonoscopy), and of the men aged 50+, only 19% had a prostate-specific antigen test in their lifetime. For women aged 40+, 55% had received a Pap smear, and 53% had a breast exam, but only 32% had a mammogram within the prior year. Among the sampled homeless population, 77% believed in the benefits of cancer screening, 79% were not fatalistic about cancer, 63% believed that early detection was efficacious, and 83% did not think it would be difficult to get screened. The majority of this population demonstrated accurate knowledge of cancer screening guidelines with the exception of endoscopy. Cancer screening rates of those surveyed were lower than the rates in California for endoscopy, prostate-specific antigen, mammography, and Pap smears. Given the lower cancer screening rates compounded by higher cancer risk factors, homeless populations need increased access to cancer screening tests, as well as education on the availability of free services. Additionally, facilities for the homeless and their staff should reinforce the purposes of cancer screening, provide more screening services, and implement institutional efforts, such as providing nutritious meals and sun protection products, to reduce high-risk behaviors and increase further access to cancer screening tests. 相似文献
1000.
Dizziness is a frequent presenting complaint in emergency department patients. Although seen in patients of all ages, it is more prevalent in patients older than 50 years of age. Vertigo represents a subset of dizziness and is defined as an illusion of movement, usually rotational, of the patient or the patient's surroundings. The illusion of motion may be of oneself (subjective vertigo) or of external objects (objective vertigo). The emergency physician should consider a large differential in the evaluation of vertigo with special attention to whether the vertigo is central or peripheral in origin. 相似文献