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11.
Children experience moderate to severe pain in the days after tonsillectomy surgery. This article describes the challenges of analyzing data from pain diaries 24 hours after ambulatory tonsillectomy surgery. Instructions were to record pain levels every 4 hours and the analgesic as given; however, the number of entries was inconsistent, making comparison of groups difficult. The use of analgesics can threaten the construct validity of cause and must be considered and controlled statistically. Opioids were converted to morphine equivalents and the nonopioids were held as a separate covariate. This article describes the steps taken to find an appropriate statistical means of dealing with inconsistent diary entries and analgesic use. Hierarchical linear modeling (HLM) provides a means to analyze unbalanced data and control for analgesics. Issues of control must be addressed in research that measures children's pain in the home. HLM can address issues of incomplete data in repeated-measures studies.  相似文献   
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Chronic myelogenous leukemia (CML) is a hematologic malignancy characterized by the presence of the Philadelphia (Ph) chromosome. Bcr- abl, the fusion gene associated with the Ph chromosome, expresses a p210bcr-abl protein that promotes a selective expansion of mature myeloid progenitor cells. Methylphosphonate (MP) oligodeoxynucleotides complementary to specific regions of the bcr-abl mRNA were incorporated in liposomes. We studied the effects of liposomal MP (L-MP) on the growth inhibition of CML-like cell lines. L-MP targeted to the breakpoint junctions of the bcr-abl mRNA inhibited the growth of CML cells. Fifty percent inhibition was achieved at approximately 1 mumol/L of L-MP oligonucleotide concentrations. The inhibitory effect was selective because growth inhibition was observed only with CML but not with control cell lines. Moreover, CML cell growth inhibition was dependent on the sequence of the MP oligodeoxynucleotides incorporated in the liposomes. The growth inhibition of CML cells by L-MP resulted from selective inhibition of the expression of the p210bcr-abl protein.  相似文献   
14.
Coronavirus disease 2019 (COVID-19) continues to impact older adults disproportionately with respect to serious consequences ranging from severe illness and hospitalization to increased mortality risk. Concurrently, concerns about potential shortages of healthcare professionals and health supplies to address these issues have focused attention on how these resources are ultimately allocated and used. Some strategies, for example, misguidedly use age as an arbitrary criterion that disfavors older adults in resource allocation decisions. This is a companion article to the American Geriatrics Society (AGS) position statement, “Resource Allocation Strategies and Age-Related Considerations in the COVID-19 Era and Beyond.” It is intended to inform stakeholders including hospitals, health systems, and policymakers about ethical considerations that should be considered when developing strategies for allocation of scarce resources during an emergency involving older adults. This review presents the legal and ethical background for the position statement and discusses these issues that informed the development of the AGS positions: (1) age as a determining factor, (2) age as a tiebreaker, (3) criteria with a differential impact on older adults, (4) individual choices and advance directives, (5) racial/ethnic disparities and resource allocation, and (6) scoring systems and their impact on older adults. It also considers the role of advance directives as expressions of individual preferences in pandemics. J Am Geriatr Soc 68:1143–1149, 2020.  相似文献   
15.
Infant oral mutilation is the practice of removing developing tooth germs, commonly the mandibular canine, in infants up to the age of 1 year. Subsequent complications include missing, impacted or hypoplastic permanent anterior and canine teeth. We report on a case of bilaterally missing lower canines thought to be due to infant oral mutilation. It is important that general dental practitioners are aware of this practice and resulting complications when treating families from sub‐Saharan East Africa.  相似文献   
16.
Laparoscopic Roux-en-Y gastric bypass (LRYGB) is the gold standard in bariatric surgery. A long-term complication can be marginal ulceration (MU) at the gastrojejunostomy. The mechanism of development is unclear and symptoms vary. Management and prevention is a continuous subject of debate. The aim was to assess the incidence, mechanism, symptoms, and management of MU after LRYGB by means of a systematic review. Forty-one studies with a total of 16,987 patients were included, 787 (4.6 %) developed MU. The incidence of MU varied between 0.6 and 25 %. The position and size of the pouch, smoking, and nonsteroidal inflammatory drugs usage are associated with the formation of MU. In most cases, MU is adequately treated with proton pump inhibitors, sometimes reoperation is required. Laparoscopic approach is safe and effective.  相似文献   
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The speed and scale of the COVID-19 pandemic has highlighted the limits of current health systems and the potential promise of non-establishment research such as “DIY” research. We consider one example of how DIY research is responding to the pandemic, discuss the challenges faced by DIY research more generally, and suggest that a “trust architecture” should be developed now to contribute to successful future DIY efforts.  相似文献   
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Population-wide variation in genomic RNA of human immunodeficiency virus type 1 (HIV-1) encompassing the V3 loop of the envelope protein was studied in serum samples of 74 newly infected individuals from three Dutch cohorts: 30 homosexual men, 32 drug users, and 12 hemophiliacs. During acute infection, HIV-1 RNA sequences present in serum are relatively homogeneous, which makes direct sequencing feasible. This offered an opportunity to study the infecting virus variants before mutations had accumulated in the new host. The sampling dates ranged from 1980 to 1991, thus spanning the entire AIDS epidemic in The Netherlands. The diversity in the sequenced region increased over time in both the homosexual and the drug-user risk groups. Furthermore, this increase was associated with an increase in antigenic variation, as witnessed by serum reactivity to a V3 peptide panel. Despite this diversification, some 1990 sequences still closely resembled the earliest 1980 sequence, making ancestral inferences problematic. No evidence was found of a change in the master sequence of the virus quasi-species over time. At the amino acid level, no risk-group-associated variation was found, but at the nucleotide level, the drug-user and homosexual/hemophiliac sequences could be distinguished on the basis of a single silent nucleotide change in the sequence encoding the tip of the V3 loop. Hemophiliac sequences could not be distinguished from those of homosexuals. In spite of the large and increasing genetic variability, all sequences were more similar to the European/American HIV consensus sequence than to that of non-Western strains.  相似文献   
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