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121.
Risk factors of peptic ulcer disease: Different impact of Helicobacter pylori in Dutch and Japanese populations? 总被引:1,自引:0,他引:1
RONALD J. SCHLEMPER SJOERD DJ VAN DER WERF JAN P. VANDENBROUCKE IZÄK BIEMOND CORNELIS BHW LAMERS 《Journal of gastroenterology and hepatology》1996,11(9):825-831
Helicobacter pylori, non-steroidal anti-inflammatory drugs, family history, blood group O, hyperpepsinogenaemia A, alcohol and smoking have been reported to be risk factors for peptic ulcer disease. The strength of causal risk factors may differ in different populations. In 215 Japanese and 493 Dutch employees of similar age, gender and type of occupation, a structured history was obtained using a questionnaire and fasting serum samples were analysed for IgG antibodies to H. pylori and pepsinogen A all in the same laboratory. A past ulcer history was verified through case notes. We found that H. pylori seropositivity, a high serum pepsinogen A and a family history of ulcer disease were significant and independent risk factors for peptic ulcer disease. For H. pylori seropositivity there was a 20-fold increased risk among the Dutch and an eight-fold increased risk among the Japanese. The seroprevalence of H. pylori was 90% in 20 Dutch subjects with a verified ulcer history and 95% in 41 Japanese ulcer subjects; it was 29% in Dutch non-ulcer subjects and 70% in Japanese non-ulcer subjects. The cumulative difference in risk to develop peptic ulcer disease at the age of 48 years between H. pylor-infected and -uninfected subjects was 24.5–3.0 = 21.5% for the Japanese and 11.8–0.5 = 11.3% for the Dutch. Duodenal ulcer disease was associated with a high coffee consumption only among the Japanese population, where this habit was much less prevalent than among the Dutch. In conclusion, the characterization of peptic ulcer risk factors as weak or strong has no universal basis: the present study shows that from a diagnostic point of view H. pylori appears to be a weaker risk factor for peptic ulcer disease in a society with a higher seroprevalence. However, from an aetiological point of view, H. pylori has an even greater impact on ulcer morbidity in the Japanese than in the Dutch population. 相似文献
122.
RAJAT DEO M.D. RONALD BERGER M.D. Ph .D.† 《Journal of cardiovascular electrophysiology》2009,20(4):466-470
Entrainment mapping is an important concept in electrophysiology that allows clinicians to characterize and treat reentrant arrhythmias. Entrainment mapping has been particularly useful for the treatment of atrial flutter, reentrant atrial tachycardias, and scar-related ventricular tachycardia. In this article, we outline the conduction properties of reentrant rhythms that permit entrainment mapping to be a useful technique. In addition, we highlight the differences between manifest and concealed entrainment. Finally, we describe useful strategies for diagnosing and treating atrial flutter and ventricular tachycardia. 相似文献
123.
SANSAN S. LO MD JULIA B. SOBOL MD NAVIN MALLAVARAM MD MARGARET CARSON CPNP CHUNG CHANG PhD PHILIP G. GRIEVE PhD RONALD G. EMERSON MD RAYMOND I. STARK MD LENA S. SUN MD 《Paediatric anaesthesia》2009,19(12):1157-1165
Background: Devices that monitor the depth of anesthesia are increasingly used to titrate sedation and avoid awareness during anesthesia. Many of these monitors are based upon electroencephalography (EEG) collected from large adult reference populations and not pediatric populations (Anesthesiology, 86, 1997, 836; Journal of Anaesthesia, 92, 2004, 393; Anesthesiology, 99, 2003, 34). We hypothesized that EEG patterns in children would be different from those previously reported in adults and that they would show anesthetic‐specific characteristics. Methods: This prospective observational study was approved by the Institutional Review Board, and informed written consent was obtained. Patients were randomized to receive maintenance anesthesia with isoflurane or sevoflurane. EEG data collection included at least 10 min at steady‐state maintenance anesthesia. The EEG was recorded continuously through emergence until after extubation. A mixed model procedure was performed on global and regional power by pooled data analysis and by analyzing each anesthetic group separately. Statistical significance was defined as P < 0.05. Results: Thirty‐seven children completed the study (ages 22 days–3.6 years). Isoflurane and sevoflurane had different effects on global and regional EEG power during emergence from anesthesia, and frontal predominance patterns were significantly different between these two anesthetic agents. Conclusions: The principal finding of the present study was that there are anesthetic‐specific and concentration‐dependent EEG effects in children. Depth‐of‐anesthesia monitors that utilize algorithms based on the EEGs of adult reference populations therefore may not be appropriate for use in children. 相似文献
124.
KANKIPATI SHANTI RAJU Lecturer/Senior Registrar RONALD W. TAYLOR Professor THELMA D. BATES Consultant 《BJOG : an international journal of obstetrics and gynaecology》1987,94(12):1212-1217
Summary. Between 1972 and 1983,49 patients with adenocarcinoma of the cervix were treated in four ways: (i) radiotherapy alone, (ii) pre- or postoperative radiotherapy and a total abdominal hysterectomy and bilateral salpingo-oophorectomy, (iii) Wertheim's hysterectomy, and (iv) pre- or postoperative pelvic radiotherapy and Wertheim's hysterectomy. The 5-year survival results for patients with FIGO Stage I disease was 90%; with Stage II disease 60%; with Stage III disease 11% and none survived with Stage IV disease. All the patients, except one (Stage 111), with well-differentiated tumours are alive and disease-free, irrespective of the type of treatment they received whereas only one patient out of the 13 who had poorly differentiated tumour is alive and disease-free. Three patients had bowel damage, one after radiotherapy alone and two after Wertheim's hysterectomy and postoperative radiotherapy. No major surgical complications occurred in this series. 相似文献
125.
BLEAVINS MICHAEL R.; MARTIN RONALD A.; de la IGLESIA FELIX A.; MUNSON ALBERT E.; MCCAY J. ANN; FOUANT MONIQUE M.; WHITE KIMBER L. JR. 《Toxicological sciences》1991,17(4):723-732
Effects of CI-949, a Novel Antiallergy Compound, on Host Resistancein Mice. BLEAVINS, M. R., MARTIN, R. A., DE LA IGLESIA, F. A.,MUNSON, A. E., MCCAY, J. A., FOUANT, M. M., AND WHITE, K. L.,JR. (1991). Fundam. Appl. Toxicol. 17, 723732. The effectof CI-949, a novel inhibitor of allergic mediator release, onimmune function was assessed with holistic mouse models of immunocompetence.Resistance to the bacterial pathogens Listeria monocytogenesand Streptococcus pneumoniae and the B16F10 melanoma cell linewas used to evaluate the potential of CI-949 to affect immunefunction. CI-949 treatment of female B6C3F1, mice increasedpulmonary tumor burden at 100 mg/kg/day in the B16F10 melanomamodel, with a no effect level of at least 50 mg/kg/day. A correlationwas seen between decreased clearance of the B16F10 cells andincreased tumor burden. However, CI-949 produced this effectonly at the maximum tolerated dose. No effect of the drug wasseen in the S. pneumoniae model. Host resistance to L. monocytogeneswas increased after CI-949 administration, with the no adverseeffect level in this model being at least equivalent to thetop dose of 100 mg/kg/day. Therefore, the immune system doesnot appear to be adversely affected or to be a specific targetfor CI-949 even at an overtly toxic. 相似文献
126.
RONALD GRUNSTEIN 《Journal of sleep research》1995,4(S1):166-170
SUMMARY It is controversial whether obstructive sleep apnoea (OSA) is a risk factor for hypertension as previous reviews of the subject have emphasized the confounding effect of obesity. We examined evidence from recent studies to reassess this debate. Cross-sectional studies from sleep clinic population (Sydney Sleep Cohort, Gothenburg Sleep Clinic Cohort), community sample (Busselton Sleep Survey, Wisconsin Sleep Cohort) and obese population (Swedish Obese Subjects Study) provide stronger evidence that the relationship between sleep apnoea and hypertension is an independent one. Moreover recent studies looking at the effect of sleep apnoea treatment have demonstrated a fall in blood pressure independent of weight change. More definitive studies are required but recent data provide increasing evidence that OSA is an independent risk factor for hypertension. 相似文献
127.
SANDRA A. SGOUTAS-EMCH JOHN T. CACIOPPO BERT N. UCHINO WILLIAM MALARKEY DENNIS PEARL JANICE K. KIECOLT-GLASER RONALD GLASER 《Psychophysiology》1994,31(3):264-271
High and low reactors were preselected on the basis of their heart rate reactivity to a speech stressor in a prescreening session. In the main study, subjects were exposed to a mental arithmetic plus noise stressor. Cardiovascular activity was recorded during baseline and stressor, and blood was drawn prior to and following the stressor for endocrine and immune assays. Results revealed that the stressor decreased the blastogenic response to concanavalin A and increased natural killer cell numbers and cytotoxicity, absolute numbers of CD8+ T-lymphocytes, nor-epinephrine and epinephrine levels, heart rate, and blood pressure responses. In addition, cortisol and natural killer cell cytotoxicity responses to the stressor differentiated individuals high versus low in heart rate reactivity. These results suggest that the interactions among the autonomic nervous system, endocrine system, and immune system are not only amenable to psychophysiological analysis but that such analyses may play an important role in illuminating underlying mechanisms. 相似文献
128.
YUEDONG WANG GRACE WAHBA CHONG GU RONALD KLEIN BARBARA KLEIN 《Statistics in medicine》1997,16(12):1357-1376
Smoothing spline ANOVA (ANalysis Of VAriance) methods provide a flexible alternative to the standard parametric GLIM (generalized linear models) methods for analysing the relationship of predictor variables to outcomes with data from large epidemiologic studies. These methods allow the visualization of relationships not readily fit by simple GLIM models, and provide for the ability to visualize interactions between the variables. At the same time, they reduce to GLIM models if the data suggest that the added flexibility is unwarranted. Using this method, we investigate risk factors for incidence and progression of diabetic retinopathy in a group of patients with older onset diabetes from the Wisconsin Epidemiological Study of Diabetic Retinopathy. We carry out four analyses to illustrate various properties of this class of methods. Some of the results confirm previous findings with use of standard methods, while others allow the visualization of more complex relationships not evident from the application of parametric methods. © 1997 by John Wiley & Sons, Ltd. 相似文献
129.
JAMES P. DAUBERT M.D. STEPHEN L. WINTERS M.D. § HARIS SUBAIUS M.A. ¶ RONALD D. BERGER M.D. ‡ KENNETH A. ELLENBOGEN M.D. † SARAH G. TAYLOR M.D. I SCHAECHTER B.S.N. R.N. ¶ ADAM HOWARD B.S. ¶ ALAN KADISH M.D. ¶ for the Defibrillators In Nonischemic Cardiomyopathy Treatment Evaluation Investigators 《Pacing and clinical electrophysiology : PACE》2009,32(6):755-761
Objectives: We evaluated whether electrophysiologic (EP) inducibility predicts the subsequent occurrence of spontaneous ventricular tachycardia (VT) or ventricular fibrillation (VF) in the Defibrillators in Nonischemic Cardiomyopathy Treatment Evaluation (DEFINITE) trial.
Background: Inducibility of ventricular arrhythmias has been widely used as a risk marker to select implantable cardioverter defibrillator (ICD) candidates, but is believed not to be predictive in nonischemic cardiomyopathy patients.
Methods: In DEFINITE, patients randomized to the ICD arm, but not the conventional arm, underwent noninvasive EP testing via the ICD shortly after ICD implantation using up to three extrastimuli at three cycle lengths plus burst pacing. Inducibility was defined as monomorphic or polymorphic VT or VF lasting 15 seconds. Patients were followed for a median of 29 ± 14 months (interquartile range = 2–41). An independent committee, blinded to inducibility status, characterized the rhythm triggering ICD shocks.
Results: Inducibility, found in 29 of 204 patients (VT in 13, VF in 16), was associated with diabetes (41.4% vs 20.6%, P = 0.014) and a slightly higher ejection fraction (23.2 ± 5.9 vs 20.5 ± 5.7, P = 0.021). In follow-up, 34.5% of the inducible group (10 of 29) experienced ICD therapy for VT or VF or arrhythmic death versus 12.0% (21 of 175) noninducible patients (hazard ratio = 2.60, P = 0.014).
Conclusions: In DEFINITE patients, inducibility of either VT or VF was associated with an increased likelihood of subsequent ICD therapy for VT or VF, and should be one factor considered in risk stratifying nonischemic cardiomyopathy patients. 相似文献
Background: Inducibility of ventricular arrhythmias has been widely used as a risk marker to select implantable cardioverter defibrillator (ICD) candidates, but is believed not to be predictive in nonischemic cardiomyopathy patients.
Methods: In DEFINITE, patients randomized to the ICD arm, but not the conventional arm, underwent noninvasive EP testing via the ICD shortly after ICD implantation using up to three extrastimuli at three cycle lengths plus burst pacing. Inducibility was defined as monomorphic or polymorphic VT or VF lasting 15 seconds. Patients were followed for a median of 29 ± 14 months (interquartile range = 2–41). An independent committee, blinded to inducibility status, characterized the rhythm triggering ICD shocks.
Results: Inducibility, found in 29 of 204 patients (VT in 13, VF in 16), was associated with diabetes (41.4% vs 20.6%, P = 0.014) and a slightly higher ejection fraction (23.2 ± 5.9 vs 20.5 ± 5.7, P = 0.021). In follow-up, 34.5% of the inducible group (10 of 29) experienced ICD therapy for VT or VF or arrhythmic death versus 12.0% (21 of 175) noninducible patients (hazard ratio = 2.60, P = 0.014).
Conclusions: In DEFINITE patients, inducibility of either VT or VF was associated with an increased likelihood of subsequent ICD therapy for VT or VF, and should be one factor considered in risk stratifying nonischemic cardiomyopathy patients. 相似文献
130.
ALEXANDER ANSTEY RONALD MARKS COLIN LONG HOSSEIN NAVABI ANTHONY PEARSE DAVID WYNFORD-THOMAS BHARAT JASANI 《The Journal of pathology》1996,178(1):84-88
The aims of this study were to confirm and substantiate the in vivo cutaneous induction of metallothionein (MT) in human skin by UVR, which we have reported in brief previously, and to make a preliminary attempt to characterize the time course of this phenomenon. Buttock skin in 32 volunteers was irradiated with 2 MED of UVB and biopsies were taken at 24 h from matched non-irradiated and irradiated sites. In the kinetic study, skin biopsies from six volunteers were taken at 0, 2, 8, 24, and 48 h after 2 MED UVB irradiation. MT was immunolocalized in formalin-fixed, paraffin-embedded tissue with the monoclonal antibody E9 by an indirect immunoperoxidase method. Statistically significant differences between immunocytochemical scores were identified between non-irradiated (NI) and irradiated (I) skin within suprabasal keratinocytes (mean: NI=1·2, I=5·1; P =0·01), superficial dermal fibroblasts (mean: NI=2, I=43; P <0·001), mid-dermal fibroblasts (mean: NI=0, I=27; P<0·001), and deep dermal fibroblasts (mean: NI=0,1=11; P<0·001. In the kinetic study, no consistent rise in MT score with time was observed for the epidermal component. In dermal fibroblasts, however, the first statistically significant rise in immunocytochemically detectable MT was detected at 2 h and this was found to plateau beyond 8 h. These results confirm that ambient levels of UV irradiation are capable of inducing MT in human skin in vivo . Taken together with the relative rapidity of the response, this suggests a physiological photoprotective role for MT in human skin cells. The lack of a kinetic increase in epidermal MT may be due to high basal levels. Induction of MT in dermal fibroblasts may reflect the effects of a diffusible factor released from keratinocytes after UVR. 相似文献