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排序方式: 共有997条查询结果,搜索用时 15 毫秒
31.
van der Waaij LA Harmsen HJ Madjipour M Kroese FG Zwiers M van Dullemen HM de Boer NK Welling GW Jansen PL 《Inflammatory bowel diseases》2005,11(10):865-871
BACKGROUND: The commensal intestinal microflora has important metabolic and perhaps also immune modulatory functions. Evidence has accumulated that the microflora plays a role in the pathogenesis of inflammatory bowel disease. Therefore, there is a growing interest in the intestinal microflora and its interaction with the host. Presumably, this interaction takes place at the mucus layer. In this study, we investigated the microflora that is present at the mucus layer and addressed the following questions. Does a specific mucus-adherent microflora exist? Is there direct contact between commensal bacteria and epithelial cells? METHODS: Snap-frozen biopsies were taken of 5 colon regions and of the terminal ileum in 9 subjects with a normal colon. Fecal samples were also collected. Bacteria were detected in cryosections with fluorescent in situ hybridization (FISH) with 16S ribosomal (r)RNA-targeted probes for all bacteria and specific probes for the major representatives of anaerobic microflora (bifidobacteria, Bacteroides, clostridia, atopobia) and aerobic microflora (Enterobacteriaceae, enterococci, streptococci, lactobacilli). RESULTS: With this sensitive technique, bacteria were only observed at the luminal side of the intestinal mucus layer. Very few microcolonies were present at the mucus layer, and the composition of the bacterial microflora present in the feces was similar to that at the mucus layer of the terminal ileum and colon regions. CONCLUSIONS: We did not observe direct contact between bacteria and epithelial cells. The equal distribution of bacterial species suggests that intestinal commensal bacteria live in suspension in the lumen and that there is no specific mucus-adherent microflora. 相似文献
32.
G.Richard Locke III Nicholas J. Talley Herschel A. Carpenter William S. Harmsen Alan R. Zinsmeister L.Joseph Melton III 《Gastroenterology》1995,109(6):1750-1756
In contrast to the dramatic decrease in the overall incidence of gastric cancer, there has been a reported increase in the incidence of cases located in the gastric cardia. The aim of this study was to identify changes in site- and histology-specific incidence rates of gastric adenocarcinoma during a 50-year period. The Rochester Epidemiology Project medical records linkage system was used to identify all cases of gastric adenocarcinoma among residents of Olmsted County, Minnesota, between 1941 and 1990 (n = 342). Each patient's complete (inpatient and outpatient) medical records were reviewed and tumor location determined from pathological, surgical, endoscopic, and radiological reports. All available histological specimens (n = 246) were reviewed independently. The overall incidence of gastric cancer decreased from 48.8 per 100,000 person-years in the 1940s to 11.6 per 100,000 in the 1980s, whereas the incidence of adenocarcinoma of the cardia did not change significantly during the 50-year period. The incidence of adenocarcinoma of the esophagogastric junction increased from 0.0 to 1.9 per 100,000 person-years, but the number of cases was small. The incidence of adenocarcinoma of the gastric cardia has not increased in this population. The reported increase in cardia cancer in other populations may be due to an increasing incidence of adenocarcinoma of the esophagogastric junction. 相似文献
33.
The identical cytogenetic marker, t(9;22)(q34;q11) (Philadelphia [Ph] translocation), is found in approximately 90%, 20%, and 2% of adult patients with chronic myelogenous leukemia (CML), acute lymphoblastic leukemia (ALL), and acute myelogenous leukemia (AML), respectively. In CML, the molecular events resulting from the Ph translocation include a break within the bcr locus on chromosome 22, transfer of the c-abl protooncogene from chromosome 9 to 22, and formation of an aberrant 210- kD bcr-abl fusion protein (p210bcr-abl). Recently, the absence of bcr rearrangement and expression of a distinct aberrant 190-kd abl protein (p190c-abl) has been described in Ph-positive ALL, with the suggestion that the two abl variants may be pathogenetically associated with myeloid v lymphoid leukemogenesis. Here we report that the genomic configuration and translation product of Ph-positive AML can be similar to that of Ph-positive ALL: the break at 22q11 may occur outside the 5.8 kb bcr region and result in expression of a 190-kD abl protein lacking these bcr sequences. Phosphokinase enzymatic activity, a fundamental property of p210bcr-abl, was also associated with AML- derived p190c-abl. Our current observations indicate that p190c-abl can be found in cells of lymphoid or myeloid lineage and is therefore unlikely to play a specific role in the development of lymphoid leukemias. Formation of p190c-abl instead of p210bcr-abl appears to be a characteristic of the acute rather than the chronic Ph-positive leukemic state. 相似文献
34.
35.
Liesbeth Mollema Irene Anhai Harmsen Emma Broekhuizen Rutger Clijnk Hester De Melker Theo Paulussen Gerjo Kok Robert Ruiter Enny Das 《Journal of medical Internet research》2015,17(5)
Background
In May 2013, a measles outbreak began in the Netherlands among Orthodox Protestants who often refuse vaccination for religious reasons.Objective
Our aim was to compare the number of messages expressed on Twitter and other social media during the measles outbreak with the number of online news articles and the number of reported measles cases to answer the question if and when social media reflect public opinion patterns versus disease patterns.Methods
We analyzed measles-related tweets, other social media messages, and online newspaper articles over a 7-month period (April 15 to November 11, 2013) with regard to topic and sentiment. Thematic analysis was used to structure and analyze the topics.Results
There was a stronger correlation between the weekly number of social media messages and the weekly number of online news articles (P<.001 for both tweets and other social media messages) than between the weekly number of social media messages and the weekly number of reported measles cases (P=.003 and P=.048 for tweets and other social media messages, respectively), especially after the summer break. All data sources showed 3 large peaks, possibly triggered by announcements about the measles outbreak by the Dutch National Institute for Public Health and the Environment and statements made by well-known politicians. Most messages informed the public about the measles outbreak (ie, about the number of measles cases) (93/165, 56.4%) followed by messages about preventive measures taken to control the measles spread (47/132, 35.6%). The leading opinion expressed was frustration regarding people who do not vaccinate because of religious reasons (42/88, 48%).Conclusions
The monitoring of online (social) media might be useful for improving communication policies aiming to preserve vaccination acceptability among the general public. Data extracted from online (social) media provide insight into the opinions that are at a certain moment salient among the public, which enables public health institutes to respond immediately and appropriately to those public concerns. More research is required to develop an automatic coding system that captures content and user’s characteristics that are most relevant to the diseases within the National Immunization Program and related public health events and can inform official responses. 相似文献36.
Maria das Gra?as WS Coriolano Luciana R Belo Danielle Carneiro Amdore G Asano Paulo José AL Oliveira Douglas Monteiro da Silva Otávio G Lins 《Dysphagia》2012,27(4):550-555
Our goal was to study deglutition of Parkinson??s disease (PD) patients and normal controls (NC) using surface electromyography (sEMG). The study included 15 patients with idiopathic PD and 15 age-matched normal controls. Surface electromyography was collected over the suprahyoid muscle group. Conditions were the following: swallow at once 10 and 20?ml of water and 5 and 10?ml of yogurt of firm consistency, and freely drink 100?ml of water. During swallowing, durations of sEMG were significantly longer in PD patients than in normal controls but no significant differences of amplitudes were found. Eighty percent of the PD patients and 20?% of the NC needed more than one swallow to consume 20?ml of water, while 70?% of the PD patients and none of the NC needed more than one swallow to consume 5?ml of yogurt. PD patients took significantly more time and needed significantly more swallows to drink 100?ml of water than normal controls. We conclude that sEMG might be a simple and useful tool to study and monitor deglutition in PD patients. 相似文献
37.
Brian P. Cunningham MD Samuel Harmsen MD Chris Kweon MD Jason Patterson MD Robert Waldrop MD Alex McLaren MD Ryan McLemore PhD 《Clinical orthopaedics and related research》2013,471(11):3679-3686
Background
Since 2003 many orthopaedic journals have adopted grading systems for levels of evidence (LOE). It is unclear if the quality of orthopaedic literature has changed since LOE was introduced.Questions/purposes
We asked three questions: (1) Have the overall number and proportion of Level I and II studies increased in the orthopaedic literature since the introduction of LOE? (2) Is a similar pattern seen in individual orthopaedic subspecialty journals? (3) What is the interobserver reliability of grading LOE?Methods
We assigned LOE to therapeutic studies published in 2000, 2005, and 2010 in eight major orthopaedic subspecialty journals. Number and proportion of Level I and II publications were determined. Data were evaluated using log-linear models. Twenty-six reviewers (13 residents and 13 attendings) graded LOE of 20 blinded therapeutic articles from the Journal of Bone and Joint Surgery for 2009. Interobserver agreement relative to the Journal of Bone and Joint Surgery was assessed using a weighted kappa.Results
The total number of Level I and II publications in subspecialty journals increased from 150 in 2000 to 239 in 2010. The proportion of high-quality publications increased with time (p < 0.001). All subspecialty journals other than the Journal of Pediatric Orthopaedics and the Journal of Orthopaedic Trauma showed a similar behavior. Average weighted kappa was 0.791 for residents and 0.842 for faculty (p = 0.209).Conclusions
The number and proportion of Level I and II publications have increased. LOE can be graded reliably with high interobserver agreement. The number and proportion of high-level studies should continue to increase. 相似文献38.
Jasvinder A. Singh Matthew R. Jensen Scott W. Harmsen David G. Lewallen 《The Journal of arthroplasty》2013
We studied the frequency and patient risk factors for postoperative periprosthetic fractures after primary total hip arthroplasty (THA). With a mean follow-up of 6.3 years, 305 postoperative periprosthetic fractures occurred in 14?065 primary THAs. In multivariable-adjusted Cox regression analyses, female gender (hazard ratio [HR], 1.48; 95% confidence interval [CI], 1.17-1.88), Deyo-Charlson comorbidity score of 2 (HR, 1.74 for score of 2; 95% CI, 1.25-2.43) or 3 or higher (HR, 1.71; 95% CI, 1.26-2.32), and American Society of Anesthesiologist class of 2 (HR, 1.84; 95% CI, 0.90-3.76) or 3 (HR, 2.45; 95% CI, 1.18-5.1) or 4 or higher (HR, 2.68; 95% CI, 0.70-10.28) were significantly associated with higher risk/hazard, and cemented implant, with lower hazard (HR, 0.68; 95% CI, 0.54-0.87) of postoperative periprosthetic fractures. Interventions targeted at optimizing comorbidity management may decrease postoperative fractures after THA. 相似文献
39.
40.
Sanskriti Sasikumar MD Melanie Cohn PhD Irene E. Harmsen BSc Aaron Loh MB BCh BAO Sang Soo Cho PhD Michel Sáenz-Farret MD MSc Ricardo Maciel MD MSc Derrick Soh MD Alexandre Boutet MD PhD Jürgen Germann PhD Gavin Elias BA Ariana Youm MA Katherine Duncan PhD Nathan C. Rowland MD PhD Antonio P. Strafella MD PhD Suneil K. Kalia MD PhD Andres M. Lozano MD PhD Alfonso Fasano MD PhD 《Movement disorders》2022,37(3):635-640