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排序方式: 共有1550条查询结果,搜索用时 31 毫秒
1.
Maggie L. Westfal David C. Chang Cassandra M. Kelleher 《Journal of pediatric surgery》2019,54(1):140-144
Purpose
The purpose of this study was to evaluate trends in demographics and outcomes of pediatric breast cancer in a United States population-based cohort.Methods
The Surveillance, Epidemiology, and End Results (SEER) database was utilized to identify all pediatric patients with malignant breast tumors between 1973 and 2014. Analysis was performed using Stata Statistical Software version 13.1. Associations between categorical variables were made using X2 test. Log-rank test was used for univariate survival analysis. Kaplan–Meier analysis investigated five-year survival rates across several variables. Adjusted analysis was performed using a Cox Proportional-Hazards regression.Results
134 patients with breast malignancies were identified. Carcinoma was the most prevalent histology (48.5%), followed by fibroepithelial tumors (FETs) (35.1%), and sarcoma (14.2%). FETs were twice as common in black compared to nonblack patients (56.3% vs. 29.0%, p?<?0.01). Analyzing histology by stage revealed that 100% of FETs were early stage disease (p?<?0.0001). 46.7% of the tumors tested were ER/PR negative, more than twice as many compared to the published adult estimate of 20.0%. Unadjusted survival analysis revealed worse survival for patients with adenocarcinoma/sarcomas, advanced stage, and high grade disease, without a survival difference between races.Conclusion
Breast cancer remains a rare malignancy among pediatric patients. Although black patients were found to have more noncarcinomatous tumors with less advanced disease, this did not confer a survival advantage.Type of study
Retrospective cohort study.Level of evidence
Level III. 相似文献2.
Cassandra A Slader l Helen K Reddel Sinthia Z Bosnic-Anticevich 《The Journal of asthma》2004,41(3):367-373
BACKGROUND: Chlorofluorocarbon (CFC)-free metered-dose inhalers (MDIs) were introduced into Australia in 1999. Device care instructions were modified (e.g., CFC-free salbutamol inhalers to be washed weekly), but this information was not communicated directly to health care professionals. OBJECTIVE: This pilot study aimed to assess the level of awareness of device care protocols for CFC-free MDIs by patients and their pharmacists. SETTING AND DESIGN: Purchasers of CFC-free MDIs were recruited from four community pharmacies. They were interviewed regarding information sources, knowledge of propellant change, and awareness of and adherence to device care protocols. The dispensing pharmacists were interviewed for knowledge of CFC-free device care. The primary outcome variable was awareness of the relevant device care protocol. RESULTS: Thirty-nine patients were interviewed. Most patients (77%) were aware of the change to CFC-free propellant. Only nine patients (23%) were aware of the need to wash the device holder, and four patients (10% of total) complied with the specified protocol. One of the ten dispensing pharmacists could describe correct device care protocols for the CFC-free MDIs. CONCLUSIONS: Although most patients are aware that MDIs are now CFC-free, there is a low level of awareness of the device care required for these inhalers, and a very low rate of compliance with recommended practice. Although the clinical impact of failing to wash the device holder is unclear, this added instruction may have substantial implications for patient satisfaction and medication delivery. Pharmaceutical manufacturers need to highlight to health care professionals any clinically important changes in device care instructions, so that appropriate information may be passed on to patients. 相似文献
3.
Braverman N Chen L Lin P Obie C Steel G Douglas P Chakraborty PK Clarke JT Boneh A Moser A Moser H Valle D 《Human mutation》2002,20(4):284-297
PEX7 encodes the cytosolic receptor for the set of peroxisomal matrix enzymes targeted to the organelle by the peroxisome targeting signal 2 (PTS2). Mutations in PEX7 cause rhizomelic chondrodysplasia punctata (RCDP), a distinct peroxisome biogenesis disorder. In previous work we described three novel PEX7 mutant alleles, including one, L292X, with a high frequency due to a founder effect. We have now extended our analysis to 60 RCDP probands and identified a total of 24 PEX7 alleles, accounting for 95% of the mutant PEX7 genes in our sample. Of these, 50% are L292X, 13% are IVS9+1G>C, and the remainder are mostly private. IVS9+1G>C occurs on at least three different haplotypes and thus appears to result from recurrent mutation. The phenotypic spectrum of RCDP is broader than commonly recognized and includes minimally affected individuals at the mild end of the spectrum. To relate PEX7 genotype and phenotype, we evaluated the consequence of the disease mutation on PEX7 RNA by Northern analysis and RT/PCR. We evaluated the function of the encoded Pex7 protein (Pex7p) by expressing selected alleles in fibroblasts from RCDP patients and assaying their ability to restore import of a PTS2 marker protein. We find that residual activity of mutant Pex7p and reduced amounts of normal Pex7p are associated with milder and variant phenotypes. 相似文献
4.
Wenge Lu Steven H. Seeholzer Mingda Han Anne‐Sophie Arnold Maria Serrano Barbara Garita Nancy J. Philp Cassandra Farthing Peter Steele Jizhen Chen Kersti K. Linask 《Developmental dynamics》2008,237(12):3577-3590
Flectin, a protein previously described to be expressed in a left‐dominant manner in the embryonic chick heart during looping, is a member of the nonmuscle myosin II (NMHC‐II) protein class. During looping, both NMHC‐IIA and NMHC‐IIB are expressed in the mouse heart on embryonic day 9.5. The patterns of localization of NMHC‐IIB, rather than NMHC‐IIA in the mouse looping heart and in neural crest cells, are equivalent to what we reported previously for flectin. Expression of full‐length human NMHC‐IIA and ‐IIB in 10 T1/2 cells demonstrated that flectin antibody recognizes both isoforms. Electron microscopy revealed that flectin antibody localizes in short cardiomyocyte cell processes extending from the basal layer of the cardiomyocytes into the cardiac jelly. Flectin antibody also recognizes stress fibrils in the cardiac jelly in the mouse and chick heart; while NMHC‐IIB antibody does not. Abnormally looping hearts of the NodalΔ 600 homozygous mouse embryos show decreased NMHC‐IIB expression on both the mRNA and protein levels. These results document the characterization of flectin and extend the importance of NMHC‐II and the cytoskeletal actomyosin complex to the mammalian heart and cardiac looping. Developmental Dynamics 237:3577–3590, 2008. © 2008 Wiley‐Liss, Inc. 相似文献
5.
Phenotypic and functional properties of murine {gamma}{delta} T cell clones derived from malaria immunized, {alpha}{beta} T cell-deficient mice 总被引:1,自引:0,他引:1
Tsuji Moriya; Eyster Cassandra L.; O'Brien Rebecca L.; Born Willi K.; Bapna Mitali; Reichel Martin; Nussenzweig Ruth S.; Zavala Fidel 《International immunology》1996,8(3):359-366
Six murine T cell clones expressing TCR were generated frommalaria immunized, ß T celldeficient mice. Phenotypiccharacterization of these clones has revealed that, in contrastto conventional ß T cells, there is a considerabledegree of heterogeneity among these clones with regard to theirsurface markers and their lymphokine profile. One clone wasfound to display significant anti-parasite activity in vivoupon adoptive transfer. We attempted to determine whether theprotective clone differs in one or more key characteristicsfrom the non-protective clones. Although no obvious patternpeculiar to the protective clone was observed, it appears thatmore than one parameter may, in combination, define a distinctprotective phenotype, and thus explain the functional differencebetween the protective and non-protective clones. 相似文献
6.
Bischoff FZ Sinacori MK Dang DD Marquez-Do D Horne C Lewis DE Simpson JL 《Human reproduction update》2002,8(6):493-500
Both intact fetal cells as well as cell-free fetal DNA are present in the maternal circulation and can be recovered for non-invasive prenatal genetic diagnosis. Although methods for enrichment and isolation of rare intact fetal cells have been challenging, diagnosis of fetal chromosomal aneuploidy including trisomy 21 in first- and second-trimester pregnancies has been achieved with a 50-75% detection rate. Similarly, cell-free fetal DNA can be reliably recovered from maternal plasma and assessed by quantitative PCR to detect fetal trisomy 21 and paternally derived single gene mutations. Real-time PCR assays are robust in detecting low-level fetal DNA concentrations, with sensitivity of approximately 95-100% and specificity near 100%. Comparing intact fetal cell versus cell-free fetal DNA methods for non-invasive prenatal screening for fetal chromosomal aneuploidy reveals that the latter is at least four times more sensitive. These preliminary results do not support a relationship between frequency of intact fetal cells and concentration of cell-free fetal DNA. The above results imply that the concentration of fetal DNA in maternal plasma may not be dependent on circulating intact fetal cells but rather be a product of growth and cellular turnover during embryonic or fetal development. 相似文献
7.
Lange Rael T. French Louis M. Bailie Jason M. Merritt Victoria C. Pattinson Cassandra L. Hungerford Lars D. Lippa Sara. M. Brickell Tracey A. 《Quality of life research》2022,31(8):2411-2422
Quality of Life Research - This study examined the clinical utility of post-traumatic stress disorder (PTSD), low resilience, poor sleep, and lifetime blast exposure as risk factors for predicting... 相似文献
8.
Barber Cassandra Burgess Raquel Mountjoy Margo Whyte Rob Vanstone Meredith Grierson Lawrence 《Advances in health sciences education : theory and practice》2022,27(2):475-489
Advances in Health Sciences Education - This study examines the way in which student characteristics and pre-admissions measures are statistically associated with the likelihood a student will... 相似文献
9.
Cassandra L. Hua Wenhan Zhang Portia Y. Cornell Momotazur Rahman David M. Dosa Kali S. Thomas 《Journal of the American Medical Directors Association》2021,22(4):913-917.e2
ObjectivesLittle is known about emergency department (ED) utilization among the nearly 1 million older adults residing in assisted living (AL) settings. Unlike federally regulated nursing homes, states create and enforce AL regulations with great variability, which may affect the quality of care provided. The objective of this study was to examine state variability in all-cause and injury-related ED use among residents in AL.DesignObservational retrospective cohort study.Setting and ParticipantsWe identified a cohort of 293,336 traditional Medicare beneficiaries residing in larger AL communities (25+ beds).MethodsWith Medicare enrollment and claims data, we identified ED visits and classified those because of injury. We present rates of all-cause and injury-related ED use per 100 person-years in AL, by state, adjusting for age, sex, race, dual-eligibility, and chronic conditions.ResultsRisk-adjusted state rates of all-cause ED visits ranged from 100.9 visits/100 AL person-years [95% confidence interval (CI) 92.8, 109.9] in New Mexico to 162.3 visits/100 AL person-years (95% CI 154.0, 174.7) in Rhode Island. The risk-adjusted rate of injury-related ED visits ranged from 18.7 visits/100 AL person-years (95% CI 17.2, 20.3) in New Mexico to 35.7 visits/100 AL person-years (95% CI 34.7, 36.8) in North Carolina.Conclusions and ImplicationsWe observed significant variability among states in all-cause and injury-related ED use among AL residents. There is an urgent need to better understand why this variability is occurring to prevent avoidable visits to the ED. 相似文献
10.
Anna Song Beeber Christine E. Kistler Sheryl Zimmerman Cassandra Dictus Kimberly Ward Claire Farel Keith Chrzan Christopher J. Wretman Marcella Boyton-Hansen Michael Pignone Philip D. Sloane 《Journal of the American Medical Directors Association》2021,22(1):156-163
ObjectivesTo determine what information is most important to registered nurses' (RNs) decisions to call clinicians about suspected urinary tract infections (UTIs) in nursing home residents.DesignWeb-based discrete choice experiment with 19 clinical scenarios.Setting and ParticipantsOnline survey with a convenience sample of RNs (N = 881) recruited from a health care research panel.MethodsClinical scenarios used information from 10 categories of resident characteristics: UTI risk, resident type, functional status, mental status, lower urinary tract status, body temperature, physical examination, urinalysis, antibiotic request, and goals of care. Participants were randomized into 2 deliberation conditions (self-paced, n = 437 and forced deliberation, n = 444). The degree to which evidence- and non–evidence-based information was important to decision-making was estimated using unconditional multinomial logistic regression.ResultsFor all nurses (22.8%) and the self-paced group (24.1%), lower urinary tract status had the highest importance scores for the decision to call a clinician about a suspected UTI. For the forced-deliberation group, body temperature was most important (23.7%), and lower urinary tract status was less important (21%, P = .001). The information associated with the highest odds of an RN calling about a suspected UTI was painful or difficult urination [odds ratio (OR) 4.85, 95% confidence interval (CI) 4.16–5.65], obvious blood in urine (OR 4.66, 95% CI 3.99–5.44), and temperature at 101.5° (OR 3.80, 95% CI 3.28–4.42). For the self-paced group, painful or difficult urination (OR 5.65, 95% CI 4.53–7.04) had the highest odds, whereas obvious blood in urine (OR 4.39, 95% CI 3.53–5.47) had highest odds for the forced-deliberation group.Conclusions and ImplicationsThis study highlighted the importance of specific resident characteristics in nurse decision-making about suspected UTIs. Future antimicrobial stewardship efforts should aim to not only improve the previously studied overprescribing practices of clinicians, but to improve nurses' assessment of signs and symptoms of potential infections and how they weigh resident information. 相似文献