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101.
Jochim S Terhaar sive Droste Mike E Craanen Rene WM van der Hulst Joep F Bartelsman Dick P Bezemer Kim R Cappendijk Gerrit A Meijer Linde M Morsink Pleun Snel Hans ARE Tuynman Roy LJ van Wanrooy Eric IC Wesdorp Chris JJ Mulder 《World journal of gastroenterology : WJG》2009,15(9):1085-1092
AIM: To assess the prevalence and location of advanced neoplasia in patients undergoing colonoscopy, and to compare the yield per indication. METHODS: In a multicenter colonoscopy survey (n = 18 hospitals) in the Amsterdam area (Northern Holland), data of all colonoscopies performed during a three month period in 2005 were analyzed. The location and the histological features of all colonic neoplasia were recorded. The prevalence and the distribution of advanced colorectal neoplasia and differences in yield between indication clusters were evaluated. Advanced neoplasm was defined as adenoma 〉 10 mm in size, with 〉 25% villous features or with high-grade dysplasia or cancer. RESULTS: A total of 4623 eligible patients underwent a total colonoscopy. The prevalence of advanced neoplasia was 13%, with 281 (6%) adenocarcinomas and 342 (7%) advanced adenomas. Sixty-seven percent and 33% of advanced neoplasia were located in the distal and proximal colon, respectively. Of all patients with right-sided advanced neoplasia (n = 228), 51% had a normal distal colon, whereas 27% had a synchronous distal adenoma. Ten percent of all colonoscopies were performed in asymptomatic patients, 7% of whom had advanced neoplasia. In the respective procedure indication clusters, the prevalence of rightsided advanced neoplasia ranged from 11%-57%. CONCLUSION: One out of every 7-8 colonoscopies yielded an advanced colorectal neoplasm. Colonoscopy is warranted for the evaluation of both symptomatic and asymptomatic patients. 相似文献
102.
Roberts-Thomson EL Saunders HI Palmer SM Powis DA Dunkley PR Bunn SJ 《European journal of pharmacology》2000,398(2):199-207
The role of Ca(2+) influx in activating phospholipase C in bovine adrenal chromaffin cells has been investigated. Phospholipase C activity in response to K(+) depolarization (56 mM) was blocked by the L-type Ca(2+) channel antagonist nifedipine and partially inhibited by the omega-conotoxins GVIA and MVIIC. In contrast, phospholipase C activity in response to histamine receptor activation was unaffected by omega-conotoxin GVIA and partially inhibited by omega-conotoxin MVIIC or nifedipine. This response was however markedly inhibited by the non-selective Ca(2+) channel antagonists La(3+) or 1-[beta-[3-(4-Methoxyphenyl)propoxy]-4-methoyphenethyl]-H-imidazol e (SKF-96365). Despite this Ca(2+) dependence phospholipase C activity was not increased during periods of "capacitative" Ca(2+) inflow generated by histamine-, caffeine- or thapsigargin-mediated depletion of internal Ca(2+) stores. Thus, while Ca(2+) influx in response to K(+) depolarization or G-protein receptor activation can increase phospholipase C activity in these cells, in the latter case it appears to be ineffective unless there is concurrent agonist occupation of the receptor. 相似文献
103.
104.
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106.
An inhibitor of the murine interleukin 2 (IL-2) dependent cell line (CTLL-2) has been demonstrated in sera from healthy subjects as well as in sera and synovial fluid from patients with inflammatory arthritides. This inhibitor inhibits the mitogenic response of normal peripheral blood mononuclear cells and seems to be primarily due to impaired IL-2 production. The inhibitor does not appear to bind to IL-2 or the IL-2 receptor. This inhibition can be reversed with IL-2 but not interleukin 1. These observations may apply to the defects in IL-2 production and response demonstrable in rheumatoid arthritis and other autoimmune disorders. 相似文献
107.
M J Ahern A C McFarlane A Leslie J Eden P J Roberts-Thomson 《Annals of the rheumatic diseases》1995,54(4):245-250
OBJECTIVES--To determine if there are specific patterns of illness behaviour in patients with arthritis, and if abnormal patterns of illness behaviour are associated with withdrawal from trials of anti-inflammatory drugs, and to examine which aspects of illness behaviour are perceived by rheumatologist to be related to the disease process. METHODS--The illness behaviour questionnaire (IBQ) was administered to 211 patients with rheumatoid arthritis (RA) and 107 patients with osteoarthritis (OA) participating in five drug trials of NSAIDs at the beginning of the studies, and was commented upon by 17 clinical rheumatologists. RESULTS--Factor analysis of 211 patients with RA produced a unique factor solution. RA patients were more preoccupied with their illness and its effects and worried more about their health than patients with OA. Patients who withdrew from drug trials showed behaviour patterns similar to those of chronic pain patients, and different from those of patients who completed the studies. When asked to account for a rheumatoid patient's response to the IBQ, rheumatologists focused on physical symptoms and did not recognise some of the psychological issues which patients saw as being relevant. CONCLUSIONS--We have demonstrated differences in illness behaviour between patients with OA and with RA. Patients withdrawing from drug trials of NSAIDs showed differences in illness behaviour compared with those successfully completing the trials. Rheumatologists underestimated the impact of the disease on their RA patients' psychological well being. 相似文献
108.
P-wave morphology in focal atrial tachycardia: development of an algorithm to predict the anatomic site of origin. 总被引:3,自引:0,他引:3
Peter M Kistler Kurt C Roberts-Thomson Haris M Haqqani Simon P Fynn Suresh Singarayar Jitendra K Vohra Joseph B Morton Paul B Sparks Jonathan M Kalman 《Journal of the American College of Cardiology》2006,48(5):1010-1017
OBJECTIVES: The purpose of this study was to perform a detailed analysis of the P-wave morphology (PWM) in focal atrial tachycardia (AT) and construct and prospectively evaluate an algorithm for identification of the anatomic site of origin. BACKGROUND: Although smaller studies have described the PWM from particular anatomic locations, a detailed algorithm characterizing the likely location of a tachycardia associated with a P-wave of unknown origin has been lacking. METHODS: The PWMs for 126 consecutive patients undergoing successful radiofrequency ablation of 130 ATs are reported. P waves were included only when the onset was preceded by a discernible isoelectric segment. P waves were classified as positive (+), negative (-), isoelectric, or biphasic. Sensitivity, specificity, and predictive values were calculated. On the basis of these results, an algorithm was constructed and prospectively evaluated in 30 new consecutive ATs. RESULTS: The distribution of ATs was right atrial (RA) in 82 of 130 (63%) and left atrial (LA) in 48 of 130 (37%). Right atrial sites included crista (n = 28), tricuspid annulus (n = 29), coronary sinus (CS) ostium (n = 14), perinodal (n = 7), right septum (n = 1), and RA appendage (n= 3). Left atrial sites included pulmonary veins (n = 32), mitral annulus (n = 8), CS body (n= 3), left septum (n = 3), and LA appendage (n = 2). In electrocardiographic lead V1, a negative or +/- P-wave demonstrated a specificity of 100% for a RA focus, and a + or -/+ P-wave demonstrated a sensitivity of 100% for a LA focus. A characteristic PWM was associated with high sensitivity and specificity at common atrial sites for tachycardia foci. A P-wave algorithm correctly identified the focus in 93%. CONCLUSIONS: Characteristic PWMs corresponding to known anatomic sites for focal AT are associated with high specificity and sensitivity. A P-wave algorithm correctly identified the site of tachycardia origin in 93%. 相似文献
109.
IA Murdoch SA Qureshi A Mitchell IC Huggon 《Acta paediatrica (Oslo, Norway : 1992)》1993,82(10):773-776
Following open heart surgery, changes in core and peripheral skin temperature and changes in the core-peripheral temperature gradient were measured in 10 children. These were correlated with changes in cardiac index, systemic vascular resistance index, mean arterial pressure and urinary output. During the study intervals, which lasted 1 h each, no changes in medical management were made. Using Spearman's rank correlation, only a change in central venous pressure was found to correlate with a change in the core-peripheral temperature gradient. We conclude that a change in the core-peripheral temperature will give valuable information about the patient's intravascular volume. 相似文献
110.
I C Roberts-Thomson 《The Australian and New Zealand journal of surgery》1978,48(3):247-251
Endoscopic retrograde cholangiopancreatography (ERCP) involves cannulation of the papilla of Vater followed by contrast radiology of the biliary and pancreatic ducts. With experience, X-ray films of the desired duct(s) can be obtained in 90% of patients, with minimal patient discomfort and a low frequency of complications. Retrograde cholangiography accurately assesses the site and cause of biliary tract obstruction. Retrograde pancreatography reveals ductal abnormalities in most patients with chronic pancreatitis and pancreatic cancer, and the nature of the abnormality usually permits differentiation of the two diseases. The diagnostic accuracy of ERCP is enhanced by cytological evaluation of pure pancreatic juice, while endoscopic sphincterotomy is a therapeutic option in selected patients with choledocholithiasis and papillary stenosis. Current developments include endoscopic aspiration biopsy of the pancreas and endoscopy of pancreatic and biliary ducts, using a miniature endoscope passed down a channel in the parent instrument. 相似文献