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The neurohormonal control of the migrating motor complex (MMC) is not fully understood. The hypothesis of the present study was that neuropeptide levels might vary with the different phases of the MMC and that a similar variation might be found in the secretions of the gastrointestinal tract. Thus, plasma and intraduodenal concentrations of vasoactive intestinal peptide (VIP), somatostatin (SOM), substance P (SP) and neurokinin A (NKA) were determined by radioimmunoassay every 10 min during two complete MMC cycles in eight male subjects. For comparison, plasma motilin (MOT) concentrations were measured. Plasma concentrations of MOT (mean peak value ± SEM; 39 ± 6 pmol L?1), but none of the neuropeptides studied, showed a cyclic variation in plasma with the different phases of the MMC. Peak intraduodenal concentrations of VIP (79 ± 23 pmol L?1),?SOM (2437 ± 432 pmol L?1) and SP (718 ± 326 pmol L?1) occurred at or at the time point before the onset of phase III of the MMC. No such correlation was observed for NKA. These results demonstrate that intraduodenal but not plasma concentrations of the neuropeptides VIP, SOM and SP show an association with phase III of the MMC. The biological relevance of this finding is yet unclear, but the results raise the possibility that gut neuropeptides may regulate fasting motility through a luminal release.  相似文献   
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Sleep bruxism based on self-report in a nationwide twin cohort   总被引:4,自引:0,他引:4  
The relative roles of genetic and environmental factors in bruxism are not known. In 1990 a questionnaire sent to the Finnish Twin Cohort yielded responses from 1298 monozygotic and 2419 dizygotic twin pairs aged 33–60 years. We used structural equation modelling to estimate genetic and environmental components of variance in the liability to bruxism. There was a significant gender difference both in childhood (P =0.001) and adult (P =0.007) bruxism. Females compared to males reported childhood bruxism ‘often’ 5.2% vs 4.1% and ‘sometimes’ 17.4% vs 17.3%, and as adults ‘weekly’ 3.7% vs 3.8% and ‘monthly’ 3.9% vs 4.6%, respectively. Bruxism in childhood and adulthood is highly correlated (0.86 in males and 0.87 in females). The proportion of total phenotypic variance in liability to bruxism attributed to genetic influences in childhood bruxism was 49% (95% CI 37–60%) in males and 64% (55–71%) in females, and for adults 39% (27–50%) among males and 53% (44–62%) among females. The correlation between the genetic effects on childhood bruxism and the genetic effects on adult bruxism was estimated in a bivariate model to be 0.95 (95% CI 0.94–0.96) in males and 0.89 (0.88–0.90) in females. Bruxism appears to be quite a persistent trait. There are substantial genetic effects on bruxism both in childhood and as adults, which appear to be highly correlated.  相似文献   
4.
International Journal of Paediatric Dentistry 2010; 20: 313–321 Background. Paediatric dentistry in Sweden has been surveyed four times over the past 25 years. During this period postgraduate training, dental health, and the organization of child dental care have changed considerably. Aim. To investigate services provided by specialists in paediatric dentistry in Sweden in 2008, and to compare with data from previous surveys. Design. The same questionnaire was sent to all 30 specialist paediatric dental clinics in Sweden that had been used in previous surveys. Comparisons were made with data from 1983, 1989, 1996 and 2003. Results. Despite an unchanged number of specialists (N = 81 in 2008), the number of referrals had increased by 16% since 2003 and by almost 50% since 1983. There was greater variation in reasons for referrals. The main reason was still dental anxiety/behaviour management problems in combination with dental treatment needs (27%), followed by medical conditions/disability (18%), and high caries activity (15%). The use of different techniques for conscious sedation as well as general anaesthesia had also increased. Conclusions. The referrals to paediatric dentistry continue to increase, leading to a heavy work load for the same number of specialists. Thus, the need for more paediatric dentists remains.  相似文献   
5.
ABSTRACT. Some 3500 adolescents answered a questionnaire anonymously. The sample represented 85 % of the students between the ages 13 to 16 and 65 % of the students between 17 to 18 in the three communities studied. The students all had middle class backgrounds. Self-reported illness differed considerably from data found in epidemiological surveys. The self-reported medical panorama was dominated by concerns about acne, tiredness, headaches, stomach pains, sports injuries and allergic disorders. One quarter to one third of the students reported such problems. Overall, 85% of the students reported that they were "completely healthy", at the same time as they also reported an average of 3.1 medical complaints. Self-initiated appointments with physicians were reported with an average of 5.5 during the last year, which is high. About 40% of the students had one complaint for which they wanted to see a physician. About 15% reported that they had had suicidal thoughts.  相似文献   
6.
The clinical incidence of lymphoedema of the arm in breast cancer patients was studied before and after general mammography screening in the country of jönköping, Sweden. There was a significant decrease of incidence of lymphoedema from 15% in 1983 to 8% in 1988. Clinical and pathological therapy data have been analysed in relation to lymphoedema. Significant factors contributing to lymphoedema were the number of lymph nodes examined and the number of pathologically positive lymph nodes. A higher proportion of patients receiving post-operative radiotherapy to the axilla developed lymphoedema, compared with those with surgery alone.
A comparison between the two groups is impossible due to the fact that post-operative radiotherapy was prescribed only to patients with pathologically positive lymph nodes.  相似文献   
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The study was made in 44 patients, of which 23 received a new endocardial electrode and 21 were investigated during pulse-generator replacement. Indication for pacemaker therapy was sino-atrial bradycardia in 12 patients and atrio-ventricular block in 32 patients. When the pacing threshold was determined with decreasing output it was found to be 0.6V/0.7 mA for new implantations and 2.0 V/2.0 mA with pulse generator replacement. When determined with increasing output the threshold was found to be an average 0.20 V/0.20 mA higher than when determined with decreasing output (threshold interval). The maximal difference observed was 0.70 V/0.55 mA. This threshold interval was of the same size irrespective of pacemaker indication and spontaneous activity and whether the electrode was newly implanted or not. Pacemaker ventricular block of Mobitz type I with Wenckebach periodicity was never observed.  相似文献   
9.
The atrioventricular (AV) interval is critical in dual chamber (DDD) pacing in patients with hypertrophic obstructive cardiomyopathy (HOCM) to obtain full ventricular capture (FVC) with maximal reduction of the left ventricular (LV) outflow gradient and optimal LV diastolic filling. We studied the relationship of FVC, fusion, spontaneous AV conduction, and the QT interval. Methods: 11 patients with various cardiac diseases and stable AV conduction received a QT sensing Diamond (tm) Vitatron, DDD pacemaker. Software was downloaded into the pacemaker. In the DDD pacing mode, with the QT interval measured from the ventricular pacing stimulus to the end of the T wave, the AV interval was shortened from 400 ms, in 20-ms steps, to 90 ms. At 90 ms the stimulation rate was increased by 30 beats/mm and the AV interval was increased stepwise. FVC and fusion was examined on the surface ECG, Results: At 400 ms interval, spontaneous AV conduction inhibited the pacemaker. Shortening the AV interval resulted in pacing with a short QT interval. Further reduction of the AV interval resulted in a longer QT interval up to a point where the QT interval became stable. This point, the bending point in the plot of measured QT interval versus shortened AV intervals, coincided with the point of FVC. The relation of the QT-AV interval plot and the point of fusion was comparable when lengthening the AV interval at a 30 beats/mm faster stimulation rate. Conclusion: The bending point in the QT interval versus AV interval plots showed a good correlation with the FVC and fusion points observed on ECG. The results suggest that automatic discrimination between fusion and full capture using QT interval measurements may be feasible.  相似文献   
10.
A series of renin inhibitors containing the dipeptide transition state mimics (2R, 4S, 5S)-5-amino-4-hydroxy-2-methyl-6-cyclohexyl hexanoic acid (Cha-Ψ[CH(OH)CH2]Ala) and (2R, 45, 5S)-5-amino-4-hydroxy-2-isopropyl-6-cyclohexyl hexanoic acid (Cha-Ψ[CH(OH)CH2]Val) were prepared. A structure-activity study, using pseudopeptide (Boc-Phe-His-Leu-Ψ[CH(OH)CH2]Val-Ile-His-OH) as our lead structure, led to a new series of inhibitors, which correspond to tripeptides and contain no natural amino acids. For example, R, S-Bpma-Ape-Cha-Ψ[CH(OH)CH2]Ala-NH2 (IC50= 1.26 nM against human plasma renin at pH 6.0; molecular weight = 564) has only two thirds of the molecular weight but twice the potency of our original lead. This new class of low molecular weight renin inhibitor displays excellent specificity toward human renin versus the related aspartic proteinase pepsin and angiotensin-1-converting enzyme. Examples are given of selected inhibitors showing encouraging evidence for intestinal absorption after intracolonic and oral administration in male Sprague-Dawley rats.  相似文献   
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