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排序方式: 共有869条查询结果,搜索用时 15 毫秒
101.
Daniel Levin Samira Bell Reijo Sund Sirpa A. Hartikainen Jaakko Tuomilehto Eero Pukkala Ilmo Keskim?ki Ellena Badrick Andrew G. Renehan Iain E. Buchan Samantha L. Bowker Jasjeet K. Minhas-Sandhu Zafar Zafari Carlo Marra Jeffrey A. Johnson Bruno H. Stricker Andrè G. Uitterlinden Albert Hofman Rikje Ruiter Catherine E. de Keyser Thomas M. MacDonald Sarah H. Wild Paul M. McKeigue Helen M. Colhoun 《Diabetologia》2015,58(3):493-504
102.
Demonstration of reversible priming of human neutrophils using platelet- activating factor 总被引:3,自引:1,他引:3
Exposure of neutrophils to agents such as lipopolysaccharide, tumor necrosis factor-alpha (TNF-alpha), and the granulocyte-macrophage colony-stimulating factor causes a major upregulation of subsequent agonist-induced NADPH oxidase activation. This priming effect is a prerequisite for neutrophil-mediated tissue damage and has been widely considered to be an irreversible process. We have investigated the potential for neutrophils to recover from a priming stimulus by studying the effects of platelet-activating factor (PAF). PAF did not stimulate respiratory burst activity directly, but caused a rapid (maximal at 10 minutes) and concentration-dependent (EC50 50.2 nmol/L) increase in N-formyl-methionyl-leucyl-phenylalanine (fMLP)-stimulated superoxide anion release. At time-points > 10 minutes, this priming effect spontaneously declined, with return to basal levels of fMLP- stimulated superoxide anion generation by 120 minutes. An identical priming time-course was observed with N-methyl carbamyl PAF, a nonmetabolizable analogue of PAF, indicating that the transient nature of PAF-induced priming was not secondary to PAF metabolism. Two structurally diverse PAF receptor antagonists (UK-74,505 and WEB 2086), added 10 minutes after PAF addition, increased the rate of decay of the priming effect. In contrast, TNF-alpha-induced priming, which was of a similar magnitude to that observed for PAF, was slower to evolve (maximal at 30 minutes) and remained constant for at least 120 minutes. The reversible nature of PAF-induced priming was confirmed by demonstrating that PAF-, but not TNF-alpha-, induced cell polarization (shape change) and CD11b-dependent neutrophil binding of albumin-coated latex beads was also transient, with return to basal, unstimulated levels by 120 minutes. Furthermore, cells that had spontaneously deprimed following PAF exposure retained their capacity to be fully reprimed by a subsequent addition of either PAF or TNF-alpha. These data imply that neutrophil priming is not an irreversible event: the demonstration of a cycle of complete priming, depriming, and repriming offers the potential for functional recycling of neutrophils at sites of inflammation. 相似文献
103.
104.
The significance of HLA-DRB1 matching on clinical outcome after HLA-A, B, DR identical unrelated donor marrow transplantation 总被引:11,自引:14,他引:11
Petersdorf EW; Longton GM; Anasetti C; Martin PJ; Mickelson EM; Smith AG; Hansen JA 《Blood》1995,86(4):1606-1613
Despite matching for serologically defined HLA-A, B, DR antigens, acute graft-versus-host disease (GVHD) is a major complication contributing to increased morbidity and mortality in patients who undergo marrow transplantation from unrelated donors. The extent to which unrecognized mismatching for alleles that encode DR1-DR18 contribute to the increased risk of acute GVHD and overall survival is unknown. We analyzed 364 patients and their HLA-A, B, DR serologically matched donors to determine whether molecular typing of DRB1 alleles can allow more accurate donor/recipient matching and thereby improve clinical outcome after marrow transplantation. DRB1 alleles were typed by sequence-specific oligonucleotide probe hybridization methods. Selected alleles were confirmed by DNA sequencing. Of the 364 pairs, 305 were matched and 59 were mismatched for DRB1. The probability of moderate to severe acute GVHD was .48 for the matched and .70 for the mismatched patients. Compared with mismatched patients, the estimated relative risk (RR) of GVHD for matched patients was .58 (95% confidence interval [CI], .40 to .85). DRB1 matching decreased the risk of transplant- related mortality (RR, .66; 95% CI, .44 to .97) and was associated with decreased overall mortality (RR, .71; 95% CI, .51 to 1.0). Therefore, matching DRB1 alleles of the donor and recipient decreases the risk of acute GVHD and improves survival after unrelated marrow transplantation. These results indicate that prospective matching of patients and donors for DRB1 alleles is warranted. 相似文献
105.
Biochemical markers of bone turnover in seronegative spondylarthropathy: relationship to disease activity 总被引:1,自引:0,他引:1
MacDonald AG; Birkinshaw G; Durham B; Bucknall RC; Fraser WD 《Rheumatology (Oxford, England)》1997,36(1):50-53
To investigate bone turnover in patients with seronegative
spondylarthropathy, a bone formation marker, type 1 procollagen carboxy-
terminal propeptide (P1CP), and resorption markers, the pyridinium
cross-links of collagen [urinary free (f) PYR and DPYR], were measured. The
median f-PYR, f-DPYR and P1CP (+/-interquartile range) were 15.8 (6.00)
nmol/mmol creatinine, 3.8 (2.2) nmol/mmol creatinine and 101.5 (38)
micrograms/1, respectively. There was a positive correlation between
resorption markers and acute-phase reactants such as C-reactive protein (r
= 0.42 for PYR, r = 0.42 for DPYR, P < 0.05), and a negative correlation
observed between P1CP and the erythrocyte sedimentation rate (r = -0.64, P
< 0.05). In the subgroup of patients with an elevated CRP concentration,
the concentration of PYR and DPYR was significantly increased (f-PYR 25.7
vs 15.8 and f-DPYR 6.6 vs 3.8, P < 0.01 for f-PYR, P < 0.05 for
f-DPYR). This study suggests than an elevation in acute-phase response in
patients with seronegative spondylarthropathy is associated with increased
concentration of bone resorption markers with a tendency for reduction in
bone formation markers. This may represent uncoupling of bone formation and
resorption, leading to bone loss in such patients.
相似文献
106.
Interaction between vitamin D receptor genotype and estrogen receptor alpha genotype influences vertebral fracture risk 总被引:8,自引:0,他引:8
Colin EM Uitterlinden AG Meurs JB Bergink AP van de Klift M Fang Y Arp PP Hofman A van Leeuwen JP Pols HA 《The Journal of clinical endocrinology and metabolism》2003,88(8):3777-3784
In view of the interactions of vitamin D and the estrogen endocrine system, we studied the combined influence of polymorphisms in the estrogen receptor (ER) alpha gene and the vitamin D receptor (VDR) gene on the susceptibility to osteoporotic vertebral fractures in 634 women aged 55 yr and older. Three VDR haplotypes (1, 2, and 3) of the BsmI, ApaI, and TaqI restriction fragment length polymorphisms and three ERalpha haplotypes (1, 2, and 3) of the PvuII and XbaI restriction fragment length polymorphisms were identified. We captured 131 nonvertebral and 85 vertebral fracture cases during a mean follow-up period of 7 yr. ERalpha haplotype 1 was dose-dependently associated with increased vertebral fracture risk (P < 0.001) corresponding to an odds ratio of 1.9 [95% confidence interval (CI), 0.9-4.1] per copy of the risk allele. VDR haplotype 1 was overrepresented in vertebral fracture cases. There was a significant interaction (P = 0.01) between ERalpha haplotype 1 and VDR haplotype 1 in determining vertebral fracture risk. The association of ERalpha haplotype 1 with vertebral fracture risk was only present in homozygous carriers of VDR haplotype 1. The risk of fracture was 2.5 (95% CI, 0.6-9.9) for heterozygous and 10.3 (95% CI, 2.7-40) for homozygous carriers of ERalpha haplotype 1. These associations were independent of bone mineral density. In conclusion, interaction between ERalpha and VDR gene polymorphisms leads to increased risk of osteoporotic vertebral fractures in women, largely independent of bone mineral density. 相似文献
107.
Ghosh D; Stewart DR; Nayak NR; Lasley BL; Overstreet JW; Hendrickx AG; Sengupta J 《Human reproduction (Oxford, England)》1997,12(5):914-920
The present study was undertaken to assess the temporal association between
the profiles of serum concentrations of oestradiol-17beta, progesterone,
chorionic gonadotrophin (CG) and relaxin in pregnancies established
naturally, and after embryo transfer, as well as in failed pregnancies in
rhesus monkeys. In naturally mated cycles (group 1) a conception rate of
75% was obtained. In group 1, the mean day of CG detection in serum was
11.5 +/- 1.9 day post-ovulation, and for relaxin, 9.0 +/- 2.5 day
post-ovulation. In group 2, embryo transfer to synchronous, non-mated
surrogate recipients was performed; seven embryo transfer cycles yielded
three pregnancies which were allowed to continue to term and normal infants
were delivered. In embryo transfer cycles the mean day of CG detection was
14.8 +/- 1.8 day post- ovulation, and for relaxin, 11.4 +/- 2.6 day
post-ovulation. A delay of about 3 days was observed in the appearance in
circulation of CG (P < 0.05) and also of relaxin (P < 0.05) between
natural mated and embryo transfer conception cycles. Significant
differences (P < 0.05 for progesterone and P < 0.03 for oestradiol)
were obtained for the areas under the curves for progesterone and
oestradiol between days 12 and 16 in conception cycles compared with failed
pregnancies. These data provide the first observation of the normal
hormonal signals associated with maternal recognition of transferred
embryos during the peri- implantation period, and suggest that the use of
such an experimental primate embryo transfer model may help to elucidate
components of maternal and embryonic signal-response mechanisms during
embryo implantation.
相似文献
108.
AG Frankfurt a.M. 《MedR Medizinrecht》2005,23(6):361-362
Abstrakt 1. Wird ein Fremdlabor vom Zahnarzt mit Reparaturarbeiten beauftragt, so ist es dann nicht Verrichtungsgehilfe des Zahnarztes, wenn es an dem für die Zurechnung erforderlichen Abhängigkeitsverhältnis zwischen Arzt und Labor fehlt.2. Fehlt es an einem Weisungsrecht des Zahnarztes gegenüber dem Labor, so ist eine Haftung für das Labor als Verrichtungsgehilfe selbst dann ausgeschlossen, wenn der Zahnarzt das Labor im eigenen Namen und auf eigene Rechnung beauftragt hat. (Leitsätze des Bearbeiters) 相似文献
109.
Postappendectomy fluid collections in children: incidence, nature, and evolution evaluated using US 总被引:1,自引:0,他引:1
At the authors' medical center, most patients with postappendectomy fluid collections are treated conservatively. Thirty-two (15%) of 216 children underwent postoperative sonography following appendectomies. In ten patients (31%), a total of 16 fluid collections were found on the initial postoperative sonogram. In the seven patients (70%) whose fluid collections were confined to the pelvis, the condition was treated conservatively and it resolved in 2-9 weeks. In three patients, fluid collections required surgical drainage and proved to be abscesses. In two of the three patients, abscesses were multiple and widely distributed in the abdomen, and the patients were clinically ill. The authors conclude that clinically symptomatic fluid collections develop postoperatively in approximately 5% of children who have undergone appendectomy for acute appendicitis and that the size and course of the fluid collection can be objectively monitored using sonography. Such fluid collections confined to the pelvis ultimately resolve with conservative, nonoperative therapy, although resolution may take up to 2 months. 相似文献
110.