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994.
Sudden infant death “syndrome”—Insights and future directions from a Utah population database analysis
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995.
Giver H Johansen MV Christensen NO Nansen P 《The Southeast Asian journal of tropical medicine and public health》1999,30(4):664-669
This study introduced a new method for estimating intestinal tissue Schistosoma japonicum egg counts, based on scraping of the mucosal layer of different sections of the intestines. Twenty-eight Danish Landrace/Yorkshire/Duroc crossbred pigs were divided into 3 groups of 15, 5 and 8 pigs, respectively. Pigs were fed either a high- or low- protein diet and were infected by an intra-muscular or per-oral route of infection with doses of either 1,000, 1,500 or 3,000 S. japonicum cercariae. The pigs were killed 9-11 weeks post infection. For all 28 pigs the intestines were divided into 3 sections: cecum, colon and rectum and the entire mucosa was scraped off the serosa of each section and homogenized. Subsequently, samples corresponding to 5 g homogenised mucosal tissue were digested and egg counts were determined and correlated to liver egg counts. In order to compare the relative distribution of eggs in the mucosa and the serosa, small intestinal wall subsamples formerly taken from each section from a subgroup of 5 pigs were homogenized and egg counts determined for both the mucosa and serosa. The number of eggs were significantly higher in the mucosa than in the serosa. Egg counts estimated from digestion of mucosa subsamples either over or underestimated egg counts based on scrapings of the entire mucosa when compared, reflecting the very patchy distribution of S. japonicum eggs in the intestinal wall. Correlating liver egg counts with the number of eggs based on scrapings from the entire mucosa from cecum, colon and rectum, respectively, significant correlations were found for 2 out of 3 groups of pigs. The present study revealed that estimating intestinal tissue egg counts based on scrapings of the entire mucosa is a reliable and convenient approach, nicely supporting the liver tissue digestion approach. In addition, a reduction of the processing time of intestinal tissue in general was achieved due to the very simple scraping technique. 相似文献
996.
Differential effects of age on large artery stiffness and minimal vascular resistance in normotensive and mildly hypertensive individuals
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Morten B. Svendsen Dinah S. Khatir Christian D. Peters Kent L. Christensen Niels H. Buus 《Clinical physiology and functional imaging》2015,35(5):359-367
Large artery stiffness and small artery structural changes are both cardiovascular risk factors. Arterial stiffness increases with age and blood pressure (BP), but it is unclear in which way large artery pulse wave velocity (PWV) and peripheral vascular resistance are related and whether age has any influence. In a cross‐sectional study, PWV and forearm minimum vascular resistance (Rmin) was compared with emphasis on the impact of age. Normotensive (n = 53) and untreated hypertensive (n = 23) subjects were included based on 24‐h BP measurements. Age ranged from 21 to 79 years with an even distribution from each age decade. PWV was assessed using tonometry. Forearm Rmin was measured by venous occlusion plethysmography at maximal vasodilatation induced by 10 min of ischaemia in combination with skin heating and hand grip exercise. In both normotensive and hypertensive subjects, PWV correlated significantly with age and BP. Based on median age, both groups were assigned into two equally large subgroups. Normotensive older (66 ± 7 years) and younger (35 ± 10 years) persons had different carotid‐femoral PWV (7·9 ± 1·8 versus 5·7 ± 0·9 m/s, P<0·01), but similar Rmin values (3·7 ± 0·9 versus 3·6 ± 1·2 mmHg/ml/min/100 ml). Hypertensive older (63 ± 6 years) and younger (40 ± 10 years) also had different PWV (8·0 ± 1·5 versus 6·7 ± 1·1 m/s, P<0·05), but the older had lower Rmin (3·1 ± 0·8 versus 4·7 ± 2·2 mmHg/ml/min/100 ml, P<0·05). In a regression analysis adjusting for age, BP, gender and heart rate, no correlation was seen between PWV and Rmin. The data suggest that age differentially affects PWV and Rmin and that BP can increase in older persons without affecting Rmin. 相似文献
997.
Interaction between beta-adrenergic receptor stimulation and nitric oxide release on tissue perfusion and metabolism 总被引:1,自引:0,他引:1
Jordan J Tank J Stoffels M Franke G Christensen NJ Luft FC Boschmann M 《The Journal of clinical endocrinology and metabolism》2001,86(6):2803-2810
Nitric oxide (NO) may be an important modulator of sympathetic tone. We used im and sc microdialysis in humans to characterize the interaction of NO synthase inhibition and adrenoreceptor stimulation on tissue perfusion, metabolism, and norepinephrine release. Microdialysis probes were perfused with L- or D-nitro-L-arginine-methyl-ester (100 micromol/L) followed by incremental doses of isoproterenol, epinephrine, or nitroprusside. Blood flow was estimated based on the ethanol dilution technique. In muscle, the increase in blood flow with isoproterenol was abolished by L-NAME. The ethanol ratio was 0.03 +/- 0.011 with D-NAME and 0.075 +/- 0.014 with L-NAME during isoproterenol treatment (1 micromol/L). The effect was less pronounced in adipose tissue. The vasodilatory effect of nitroprusside was similar with D- and L-NAME. L-NAME augmented isoproterenol- and epinephrine-induced glycerol release. Dialysate glycerol during 1 micromol/L isoproterenol was 47 +/- 6.7 micromol/L with D-NAME and 72 +/- 15 micromol/L with L-NAME. In skeletal muscle, dialysate norepinephrine during 1 micromol/L isoproterenol treatment was 0.73 +/- 0.17 and 1.3 +/- 0.15 nmol/L with D- and L-NAME, respectively. We conclude that NO synthase inhibition attenuates beta(2)-adrenoreceptor-mediated vasodilation and enhances beta-adrenoreceptor-mediated lipolysis. These effects are in part mediated through an increase in interstitial norepinephrine concentrations. The data are consistent with the idea that in humans, NO is important in modulating and ameliorating sympathetic effects in peripheral tissues. 相似文献
998.
CARD4/NOD1 is not involved in inflammatory bowel disease 总被引:8,自引:0,他引:8
Zouali H Lesage S Merlin F Cézard JP Colombel JF Belaiche J Almer S Tysk C O'Morain C Gassull M Christensen S Finkel Y Modigliani R Gower-Rousseau C Macry J Chamaillard M Thomas G Hugot JP;EPWG group;EPIMAD group 《Gut》2003,52(1):71-74
BACKGROUND AND AIMS: Inflammatory bowel diseases (IBD), including Crohn's disease (CD) and ulcerative colitis (UC), are complex genetic disorders. CARD15/NOD2, a member of the Ced4 superfamily which includes Apaf-1 and CARD4/NOD1, has recently been associated with genetic predisposition to CD but additional genetic factors remain to be identified. Because CARD4/NOD1 shares many structural and functional similarities with CARD15, we tested its putative role in IBD. PATIENTS AND METHODS: The 11 exons of CARD4 were screened for the presence of variants in 63 unrelated IBD patients. The only non-private genetic variation encoding for a substitution in the peptidic chain was genotyped in 381 IBD families (235 CD, 58 UC, 81 mixed, and seven indeterminate colitis families) using a polymerase chain reaction-restriction fragment length polymorphism procedure. Genotyping data were analysed by the transmission disequilibrium test. RESULTS: Five of nine sequence variations identified in the coding sequence of the gene encoded for non-conservative changes (E266K, D372N, R705Q, T787M, and T787K). Four were present in only one family. The remaining variant (E266K), which exhibited an allele frequency of 0.28, was not associated with CD, UC, or IBD. Furthermore, IBD patients carrying sequence variations in their CARD4 gene had a similar phenotype to those with a normal sequence. CONCLUSION: Our results suggest that CARD4 does not play a major role in genetic susceptibility to IBD. 相似文献
999.
A Amidi S Christensen M Mehlsen A B Jensen A D Pedersen R Zachariae 《British journal of cancer》2015,113(5):794-801
Background:
There is growing concern among breast cancer (BC) patients and survivors about cognitive impairment following systemic treatments. The aim of the present study was to investigate the long-term effects of standard systemic adjuvant therapies on subjective cognitive impairment (SCI) in a large nationwide cohort of BC survivors 7–9 years after primary surgery.Methods:
Participants were recruited from the nationwide Psychosocial Factors and Breast Cancer inception cohort of Danish women treated for primary BC. SCI was assessed with the Cognitive Failures Questionnaire and women allocated to systemic treatment according to nationwide standard protocols were compared with women who had not received any systemic treatments.Results:
A total of 1889 recurrence-free survivors were eligible for analysis. No difference in SCI was found between survivors across standardized systemic treatment protocols when analyses were stratified by menopausal status and adjusted for possible sociodemographic and treatment-related confounders. The frequency of significant SCI in a subgroup of survivors in the age range 65–74 years was ∼7%.Conclusions:
No differences in long-term SCI at 7–9 years post surgery were found between women who had received systemic therapies and those who had not. Furthermore, the observed proportion of survivors with significant SCI was comparable to normative data. These results are important to communicate to patients, survivors, and clinicians alike, especially in the light of increasing concern about cognitive impairment following systemic therapies. 相似文献1000.
A randomised phase II trial of selumetinib vs selumetinib plus temsirolimus for soft-tissue sarcomas
Z Eroglu H A Tawbi J Hu M Guan P H Frankel N H Ruel S Wilczynski S Christensen D R Gandara W A Chow 《British journal of cancer》2015,112(10):1644-1651