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1.
Wenjing Tao Miia Artama My von Euler-Chelpin Mark Hull Rickard Ljung Elsebeth Lynge Guðríður H. Ólafsdóttir Eero Pukkala Pål Romundstad Mats Talbäck Laufey Tryggvadottir Jesper Lagergren 《International journal of cancer. Journal international du cancer》2020,147(3):728-735
Obesity is a risk factor for colorectal cancer. Yet, some research indicates that weight-reducing bariatric surgery also increases colorectal cancer risk. Our study was undertaken because current evidence examining bariatric surgery and risk of colorectal cancer is limited and inconsistent. This population-based cohort study included adults with a documented obesity diagnosis in Denmark, Finland, Iceland, Norway or Sweden in 1980–2015. The incidence of colorectal cancer in participants with obesity who had and had not undergone bariatric surgery was compared to the incidence in the corresponding background population by calculating standardized incidence ratios (SIR) with 95% confidence intervals (CI). Additionally, operated and nonoperated participants with obesity were compared using multivariable Cox regression, providing hazard ratios (HR) with 95% CIs adjusted for confounders. Among 502,772 cohort participants with an obesity diagnosis, 49,931(9.9%) underwent bariatric surgery. The overall SIR of colon cancer was increased after bariatric surgery (SIR 1.56; 95% CI 1.28–1.88), with higher SIRs ≥10 years postsurgery. The overall HR of colon cancer in operated compared to nonoperated participants was 1.13 (95% CI 0.92–1.39) and 1.55 (95% CI 1.04–2.31) 10–14 years after bariatric surgery. Bariatric surgery did not significantly increase the risk of rectal cancer (SIR 1.14, 95% CI 0.83–1.52; HR 1.08, 95% CI 0.79–1.49), but the risk estimates increased with longer follow-up periods. Our study suggests that bariatric surgery is associated with an increased risk of colon cancer, while the support for an increased risk of rectal cancer was weaker. 相似文献
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Toxic cardiomyopathy: the effect of antipsychotic-antidepressant drugs and calcium on myocardial protein degradation and structural integrity 总被引:5,自引:0,他引:5
In the nonrecirculating isolated perfused rat heart it has recently been described that basal myocardial protein degradation is suppressed by 30% within 5 min of maximal beta-adrenergic receptor occupancy under 5 X 10(-7) M isoproterenol (Lockwood, 1985, Biochem. J. 231, 299-308). This adrenergic-controlled proteolytic process presumably contributes to the well-known normal coordination of myocardial protein mass with functional demand. It is presently reported that elevated intracellular calcium is among the messengers that somehow suppress protein degradation. Acute elevation of extracellular calcium to a maximal concentration of 9.0 mM mimicked the simultaneous effects of isoproterenol on increasing inotropy and decreasing protein degradation, although this concentration was eventually lethal. Conversely, infusion of trifluoperazine (TFP), a calmodulin-blocking antipsychotic drug, caused stimulation of protein degradation above basal levels within 5 min. The stimulation of degradation by 30-60% was transient at 5 X 10(-7) M and returned to the control level in 5-10 min. However, TFP produced massive irreversible release of amino acid peptides and proteins at 10(-5) M within 30 min, followed by grossly observable cell structural disruption and cell separation. The degradative stimulation caused by TFP was potentiated by lowering the normal 2.5-mM extracellular Ca2+ concentration to 1.25 mM. Trifluoperazine at 10(-5) M caused longitudinal separation of myofibrils by disrupting lateral attachments between adjacent Z lines, leading to a loss of lateral myofibrillar registry followed by myofibrillar degeneration. Spot desmosomes were disrupted, leading to lateral cell separation; however, the fascia adherens region of the intercalated disks remained intact and cells maintained end-to-end attachment. Perfusion under the low extracellular Ca2+ concentration of 0.1 mM for 0.5 hr caused separation of the fascia adherens region and spot desmosomes of the intercalated disks as well as disruption of cytoplasmic myofibrils and other changes. Although the structural disorganization caused by perfusion with low (0.1 mM) Ca2+ were similar to those caused by TFP, cells also lost end to end attachment under low Ca2+. Amitriptyline (10(-5) M), thioridazine (10(-5) M), and calmidazolium (10(-6) M) stimulated protein degradation and caused structural damage. It is speculated that the above Ca2+-related phenomena describe the mechanism of the well-known toxic cardiomyopathy resulting from overdoses of some of the antipsychotic-antidepressant drugs.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
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Identification of a Klebsiella pneumoniae strain associated with nosocomial urinary tract infection. 下载免费PDF全文
K S Kil R O Darouiche R A Hull M D Mansouri D M Musher 《Journal of clinical microbiology》1997,35(9):2370-2374
To differentiate between relapse of infection and reinfection of the urinary tract due to Klebsiella pneumoniae, 33 K. pneumoniae isolates collected from 20 patients with spinal cord injury (SCI) over 2 years were typed by genomic fingerprinting by repetitive-element PCR. Clinical isolates obtained from the same patients with recurrent episodes of urinary tract infection (UTI) revealed identical genomic fingerprints indicating relapse of UTI due to K. pneumoniae, despite appropriate antibiotic therapy. Seventeen isolates obtained from 8 of the 20 SCI patients shared a common genotype, termed RD6. Among non-SCI patients residing in other nursing units, the RD6 genotype was found in 5 of 10 patients with K. pneumoniae UTI but in only 1 of 20 patients with K. pneumoniae infection that did not involve the urinary tract, suggesting a strong association of this genotype with UTI. All RD6 isolates exhibited strong adherence (> or =50 adherent bacteria per cell) to HEp-2 cells, whereas other K. pneumoniae isolates generally did not adhere to or adhered very weakly to HEp-2 cells (< or =5 adherent bacteria per cell). Adherence was inhibited either by 4% D-mannose or by anti-type 1 fimbrial rabbit serum. These results suggest that the capacity of K. pneumoniae RD6 isolates to cause UTI may be mediated by its striking adherence to mammalian cells. 相似文献
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M. S. Levine A. M. Adinolfi R. S. Fisher C. D. Hull D. Guthrie N. A. Buchwald 《Brain research》1988,440(2):267-279
These studies provide information on the changes in the ultrastructure in the caudate nucleus of aged cats. The major findings was that there was a decrease in the density of synapses in caudate neuropil. This decrease occurred in animals after 3 years of age and remained relatively constant in older animals. In conjunction with this change a population of unusually long synapses also occurred. These larger synaptic appositions were associated with enlarged spine heads. The caudate also showed a number of qualitative ultrastructural alterations. Many neurons contained accumulations of lipofuscin or lipopigment granules in aged animals. These inclusions occurred in both soma and dendrites of neurons and all types of glial cells. A unique configuration of collapsed agranular cisterns also was observed in aged animals. The present results indicate that decreases in synaptic density may by one morphological event underlying functional alterations observed in caudate neurons in aged cats. 相似文献
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Does changing from mercury to electronic blood pressure measurement influence recorded blood pressure? An observational study. 下载免费PDF全文
Richard J McManus Jonathan Mant Martyn R P Hull F D Richard Hobbs 《The British journal of general practice》2003,53(497):953-956
Mercury sphygmomanometers have been commonly used in primary care to measure blood pressure but are associated with bias. Electronic blood pressure machines are being introduced in many practices and have anecdotally been associated with higher recorded blood pressure. This study examined recorded blood pressure in four practices before and after electronic blood pressure machine introduction. No consistent change in mean blood pressure was apparent following their introduction, but there was a large and significant fall in terminal digit preference suggesting improved precision of recording. 相似文献
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Cleveland Clinic Lerner College of Medicine (CCLCM) is an innovative, five-year medical education track within Case Western Reserve University School of Medicine (Case) with a focused mission to attract and educate a limited number of highly qualified persons who seek to become physician investigators. CCLCM curriculum governance, faculty appointments and promotions, and admissions committees are integrated with respective Case committees. The CCLCM curriculum is based on faculty-defined professional attributes that graduates are expected to develop. These attributes were used to create curricular and assessment principles that guided the development of an integrated basic science, clinical science, and research curriculum, conducted in an active learning environment. An organ-system approach is used to solidify an understanding of basic science discipline threads in the context of relevant clinical problems presented in PBL and case-based discussion formats. Clinical skills are introduced in the first year as part of the two-year longitudinal experience with a family practice or internal medicine physician. The research program provides all students with opportunities to learn and experience basic and translational research and clinical research before selecting a research topic for their 12- to 15-month master-level thesis project. All Case students participate in required and elective clinical curriculum after the second year, but CCLCM students return to the Cleveland Clinic on selected Friday afternoons for program-specific research and professionalism-learning activities. A unique portfolio-based assessment system is used to assess student achievements in nine competency areas, seven of which reflect the Accreditation Council for Graduate Medical Education competencies. 相似文献