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41.
Summary The relationship between chronic pancreatitis (CP) and extrapancreatic cancer has been debated in the recent years. In prospective studies, it has been found that pancreatic cancer develops in 0–5% of patients with chronic pancreatitis. Many papers describe an increased relative risk for developing extrapancreatic cancer in patients suffering from chronic pancreatitis. In this study including 181 patients with CP, we found 14 patients with extrapancreatic cancer (three of these had two different types of cancer). No patient had pancreatic cancer. It was found that the respiratory airways and upper gastrointestinal tract were the dominating locations (five and four cases, respectively), but also genital and hemolymphopoietic cancers were represented (four and two cases, respectively). Two patients had metastatic cancer with unknown primary tumor. The patients with cancer tended to be older than those without cancer. The patients with CP had a 2.43 times greater risk of developing cancer than the general Danish population (age and sex standardized comparison). The relatively large number of cancers in the upper gastrointestinal tract and respiratory airways suggest that tobacco and alcohol may be responsible, as these organs have the highest exposure to these compounds, which are well known carcinogens.  相似文献   
42.
Data on the bacteriological findings, diagnostic measures and clinical course of 875 patients with bacterial meningitis are presented. Findings from the medical records and from a follow-up questionnaire survey of 667 of these cases revealed no significant difference between patients treated with antibiotics before admission (pretreated) and those who were not treated before admission (non-pretreated) with respect to clinical condition on admission, mortality and late sequelae. Pretreatment was, however, associated with a longer duration of symptoms. Apart from cases due to Neisseria meningitidis, there were no significant differences in diagnostic findings between pretreated and non-pretreated cases. In the group of pretreated meningococcal patients, however, positive blood cultures, pleiocytosis in the cerebrospinal fluid (CSF) and positive cultures from sites other than blood and CSF were less frequent than in the non-pretreated cases.  相似文献   
43.
This study compared the use of antihypertensive treatment and blood pressure (BP) controls between patients with diabetic kidney disease (DK+) and patients with non-diabetic kidney disease (DK-) exhibiting moderate-to-severe chronic renal failure who did not need renal replacement therapy. A cross-sectional survey included all renal patients with s-creatinine at ?200 micromol/l attending regular control sessions at six renal units in Norway. Of the 351 patients included, 73 (20.8%) were DK+. The proportion reaching a BP goal of <130/80 mmHg was similar in DK+ and DK- (14.1% vs 13.6%, p = 0.92), while 38% and 39% achieved a BP of <140/90 mmHg, respectively. The systolic BP goal was more difficult to achieve than the diastolic BP goal in DK+ patients (35% vs 15%) despite a mean of three different types of drugs being used. Loop diuretics and beta-adrenergic-receptor antagonists were the most frequently prescribed drugs, and the use of angiotensin-converting enzyme inhibitors or angiotensin-II-receptor antagonists declined when renal function deteriorated, from 80% to 0% and from 66% to 20% in the DK+ and DK- groups, respectively (p = 0.001). Thus, despite the use of multiple antihypertensive drugs, controlling BP - especially the systolic BP - is difficult in high-risk patients with chronic renal failure caused by diabetic kidney disease.  相似文献   
44.
Möllmann H  Elsässer A  Hamm CW 《Herz》2005,30(3):181-188
Cardiovascular disease is the leading cause of death in western societies, with further increasing incidence. Therefore both, primary and secondary prevention play a pivotal role. Medicamentous prevention schemes include the antithrombotic drugs acetylsalicylic acid (ASS) and clopidogrel. A number of studies tested the efficacy and safety of ASS for primary prevention. A meta-analysis of these primary prevention trials could demonstrate a decrease of cardiovascular events only for patients being at high cardiovascular risk. However, since ASS does not influence the mortality but is significantly increasing the risk for bleeding, careful risk stratification is indispensable prior to preventive chronic administration of the drug. Therapy with ASS in the secondary prevention is commonly accepted and clearly evidence-based given that a meta-analysis of 145 trials could demonstrate a significant decrease in mortality. A daily dose of 100 mg has been shown to achieve sufficient antithrombotic effects with an acceptable rate of side effects. Clopidogrel is currently not used for primary prevention, since evidence is lacking and the costs are high. For secondary prevention after acute coronary syndromes, a decrease of cardiovascular events could be demonstrated for clopidogrel. This benefit was especially pronounced after percutaneous coronary interventions. However, clopidogrel could not decrease the mortality. Therefore, long-term treatment with clopidogrel in the secondary prevention should be based on a critical appraisal of risk and benefit on the one hand and socioeconomic aspects on the other hand.  相似文献   
45.
The brain acts as an integrated information processing system, which methods in cognitive neuroscience have so far depicted in a fragmented fashion. Here, we propose a simple and robust way to integrate functional MRI (fMRI) with single trial event-related potentials (ERP) to provide a more complete spatiotemporal characterization of evoked responses in the human brain. The idea behind the approach is to find brain regions whose fMRI responses can be predicted by paradigm-induced amplitude modulations of simultaneously acquired single trial ERPs. The method was used to study a variant of a two-stimulus auditory target detection (odd-ball) paradigm that manipulated predictability through alternations of stimulus sequences with random or regular target-to-target intervals. In addition to electrophysiologic and hemodynamic evoked responses to auditory targets per se, single-trial modulations were expressed during the latencies of the P2 (170-ms), N2 (200-ms), and P3 (320-ms) components and predicted spatially separated fMRI activation patterns. These spatiotemporal matches, i.e., the prediction of hemodynamic activation by time-variant information from single trial ERPs, permit inferences about regional responses using fMRI with the temporal resolution provided by electrophysiology.  相似文献   
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48.
OBJECTIVE: In a one-year study of 5 patients with chronic atrophic gastritis (CAG), pernicious anaemia (PA), hypergastrinaemia and enterochromaffin-like (ECL) cell tumours, the somatostatin analogue octreotide LAR (long-acting release) in a dose of 20 mg given intramuscularly at monthly intervals had an antiproliferative effect on the ECL cells. The aim of the present study was to follow neuroendocrine (NE) markers in the blood and macroscopic and histopathological changes in the stomach during a 12-month follow-up after discontinuation of octreotide LAR treatment. MATERIAL AND METHODS: Five patients underwent upper gastrointestinal endoscopy at 6 and 12 months' follow-up after octreotide LAR treatment. Biopsies from flat, oxyntic mucosa and from tumours were obtained. Sections were stained with haematoxylin-erythrosin and immunostained for the NE cell marker chromogranin A (CgA). Serum gastrin and CgA were measured every 3 months. RESULTS: The number of visible tumours was unchanged (7) at 12 months' follow-up. One lesion showed carcinoid tumour and the others various degrees of linear and micronodular NE hyperplasia. At the same time-point, biopsies from flat, oxyntic mucosa showed a slightly (non-significant) elevated number of CgA immunoreactive (IR) cells. Serum gastrin increased from 186+/-50 pM (mean+/-SEM) to 603+/-109 pM (normal < 40 pM); p<0.05, and serum CgA increased non-significantly from 25+/-2 ng/ml (normal < 30 ng/ml) to 61+/-11 ng/ml. CONCLUSIONS: During follow-up, slightly elevated levels of serum CgA and CgA IR cells in the oxyntic mucosa, without significant recurrence of ECL cell carcinoids, were observed.  相似文献   
49.
Summary Beta-blockers with less cardiodepressive effect than traditional nonselective beta1+2-blocking agents could be useful in the treatment of hypertension, provided the reduction in blood pressure was satisfactory. Epanolol, a selective beta1-receptor blocker with intrinsic sympathomimetic activity, induced a fall in intraarterial pressure of 8% at rest sitting and 11% during 100 W bicycle exercise after the first dose of 200 mg in 12 patients with essential hypertension. Heart rate, stroke index, and cardiac index initially fell by 14%, 11%, and 23%, respectively. The total peripheral resistance index increased by 21% after 2 hours, and then reverted towards the pretreatment level. After 10 months of epanolol treatment (mean 300 mg/day), the reduction in arterial pressure was 5% at rest and 10% during exercise. Cardiac index and heart rate were still reduced 14–21%, while total peripheral resistance was unchanged or slightly increased (2–10%). Twenty-four hour ambulatory blood pressure was higher on epanolol (300 mg/day) than on atenolol (150 mg/day) treatment (137/97 vs. 128/91 mmHg). Thus, the achieved blood pressure reduction induced by epanolol was moderate, while other characteristics of beta-receptor blockade, in particular, the reduction of heart rate and cardiac output, were maintained. This suggests that the compound may be useful for other cardioavascular disorders, e.g., angina pectoris in patients without hypertension or cardiac arrhythmia.  相似文献   
50.
OBJECTIVE: The aim was to examine the electromechanical effects of dofetilide, a new class III antiarrhythmic agent, in isolated guinea pig ventricular muscle during hypoxia. METHODS: Hypoxia was induced by superfusing guinea pig right ventricular papillary, muscles with Tyrode's solution gassed with 95% N2 + 5% CO2 [PO2 = 5.3(SEM 1.3) kPa]. Prior to hypoxia, the preparations were either pretreated for 30 min with 0.1 microM dofetilide (n = 6) or with 100 microM glibenclamide (a blocker of ATP sensitive K+ channels, n = 6), or not pretreated (n = 6). Sixteen additional preparations were exposed to 1 mM nicorandil (an activator of ATP sensitive K+ channels) in the absence (n = 6) and presence of dofetilide (n = 6) or glibenclamide (n = 4). Transmembrane action potentials and developed force were recorded using conventional microelectrode techniques and a force transducer. RESULTS: During normoxia, dofetilide markedly increased APD90 from 236(SEM 6) ms to 298(7) ms (p < 0.05) and the effective refractory period (ERP) from 248(5) ms to 315(6) ms (p < 0.05). In the drug free group, 60 min hypoxia decreased APD90 by 47(5)% (p < 0.05), ERP by 48(4)% (p < 0.05) and developed force by 71(6)% (p < 0.05) of baseline, respectively. These hypoxia induced effects were significantly attenuated after pretreatment with dofetilide or glibenclamide. Nicorandil decreased APD90 by 45(5)% (p < 0.05), ERP by 44(6)% (p < 0.05), and developed force by 69(10)% (p < 0.05) of baseline, respectively. Pretreatment with dofetilide or glibenclamide also significantly attenuated the nicorandil induced decreases in APD90, ERP, and developed force. CONCLUSIONS: Dofetilide, like glibenclamide, effectively attenuates hypoxia and nicorandil induced action potential shortening and the associated reduction in contractile force. Thus dofetidile would be expected to retain its antiarrhythmic efficacy during myocardial hypoxia or ischaemia.  相似文献   
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