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991.
OBJECTIVE: To assess the association between Chlamydia trachomatis antibodies, antibodies to C trachomatis heat shock proteins 60 and 10, and C-reactive protein (CRP) levels in maternal serum measured by highly sensitive CRP assay during the first trimester and spontaneous preterm delivery before 37 weeks of gestation. Methods: This was a nested case-control study of 104 spontaneous preterm singleton deliveries (cases) and 402 term singleton deliveries, as controls, of mothers belonging to the population-based Northern Finland 1966 Birth Cohort. Data on 2,309 first deliveries were available from the Finnish Medical Birth Register. Serum C trachomatis and C pneumoniae antibodies were measured by the microimmunofluorescence test and chlamydial heat shock proteins 60 and 10 antibodies by enzyme immunoassay using recombinant proteins as antigens, and highly sensitive CRP levels were quantified with highly sensitive immunoenzymometric assay. Results: Highly sensitive CRP levels were higher and C trachomatis immunoglobulin G levels (pools and individual serotypes) were more often present (thought not nominally significantly in all cases) in the women with preterm compared with term deliveries. Elevated immunoglobulin G levels of C trachomatis antibodies or elevated highly sensitive CRP levels alone, however, did not increase the estimated risk for preterm delivery, but when they were present simultaneously, the estimated risk for preterm delivery was 4-fold (odds ratio 4.3, 95% confidence interval 2.0-9.3). Among the women delivered at or before 34 weeks of gestation, the estimated risk was even more evident (odds ratio 5.6, 95% confidence interval 2.1-14.5). The preterm delivery rate was 26.5% for those with C trachomatis antibodies and 18.8% for those without C trachomatis antibodies. CONCLUSION: The results of the present study suggest that chlamydial infection in the first trimester is associated with preterm delivery. LEVEL OF EVIDENCE: II-2.  相似文献   
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993.
The authors examined the relationship between functional epidermal growth factor gene A61G polymorphism and cardiac autonomic control in a sample of 75 young adults. Heart rate, preejection period, and respiratory sinus arrhythmia were measured continuously during rest and a set of challenging tasks. The functional G allele of the epidermal growth factor gene was associated with lower heart rate F(5,32), 6.92, p = 0.014, eta2 = 0.19, and higher respiratory sinus arrhythmia F(5,32), 4.71, p = 0.038, eta2 = 0.14, among women during the rest, but was not related to with cardiovascular reactivity for challenges in women or in men. The present findings suggest that epidermal growth factor A61G polymorphism is associated with cardiac control in women.  相似文献   
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996.
The present study investigated the role of endogenous opioids in the expression of defensive behaviors (DBs) and the suppression of cell proliferation (CP) in the dentate gyrus (DG) induced by exposure to predator odor, trimethyl thiazoline (TMT). Adult male rats were injected with either naltrexone (an opioid antagonist, 5 mg/kg) or saline 30 min before exposure to either TMT or a control odor. Behavior was scored for the first 15 min of odor exposure. Bromodeoxyuridine (BrdU, 200 mg/kg) was then injected, and the rats were perfused 1 hr later. Exposure to TMT increased the expression of DBs and suppressed the number of proliferating cells in the DG. Pretreatment with naltrexone attenuated the effects of TMT on DB expression but did not attenuate the effects of TMT on CP. In addition, naltrexone administration suppressed CP in the absence of TMT. These results demonstrate a dissociation between DBs and regulation of CP in the DG.  相似文献   
997.
Oxidative stress plays a significant role in the pathogenesis of coronary artery disease (CAD). A p22(phox)-based NAD(P)H oxidase acts as a potent superoxide-generating system in the vasculature. We studied the association of the A640G and the C242T polymorphisms with clinical risk factors, endothelial function, and severity of CAD in a cohort of 216 patients referred for coronary angiography. The frequency of p22(phox) genotypes for AA, AG, and GG was 22.5, 52.3, and 25.2%, and for CC, CT, and TT 35.5, 51.3, and 13.2%, respectively. The A640G and the C242T polymorphisms were not associated with severity of CAD and endothelial function. The frequency distribution of the genotypes among patients with or without angiographically significant CAD did not reach statistical significance. Our study does not support a functional role for the A640G or C242T polymorphisms either in the severity of CAD or in determining endothelial function in older men.  相似文献   
998.
Finne P  Auvinen A  Aro J  Juusela H  Määttänen L  Rannikko S  Hakama M  Tammela TL  Stenman UH 《European urology》2002,41(6):619-26; discussion 626-7
Background and Objective: Approximately 70% of the men with an elevated serum prostate-specific antigen (PSA) identified in prostate cancer screening do not have prostate cancer. Other available diagnostic variables may be utilized to reduce the number of false positive PSA results, but few algorithms for calculation of the combined impact of multiple variables are available. The objective of this study was to establish nomograms showing the probability of detecting prostate cancer at biopsy on the basis of total PSA, and the percentage of free PSA in serum, prostate volume and digital rectal examination (DRE) findings.Methods: In a randomized, population-based prostate cancer screening trial 10 284 men aged 55–67 years were screened during 1996 and 1997 in two metropolitan areas in Finland. Results for men (n=758) with a serum PSA of 4–20 μg/l were used to establish the risk nomograms. Of these 200 (26%) had prostate cancer at biopsy.Results: Prostate cancer probability depended most strongly on the percentage of free PSA. Total PSA, prostate volume, and DRE also contributed to prostate cancer probability, whereas age and family history of prostate cancer did not. More false positive PSA results could be eliminated by using the multivariate risk model rather than the percentage of free PSA (p<0.001) or PSA density (p=0.003) alone.Conclusions: Wide variation in probability of detecting prostate cancer among screened men with a serum PSA of 4–20 μg/l was observed. The nomograms established can be used to avoid or defer biopsy in men with a low prostate cancer probability in spite of a serum PSA level exceeding 4 μg/l.  相似文献   
999.
Background: The authors report a positron emission tomography (PET) study on humans with parallel exploration of the dose-dependent effects of an intravenous (propofol) and a volatile (sevoflurane) anesthetic agent on regional cerebral blood flow (rCBF) using quantitative and relative (Statistical Parametric Mapping [SPM]) analysis.

Methods: Using H215O, rCBF was assessed in 16 healthy (American Society of Anesthesiologists [ASA] physical status I) volunteers awake and at three escalating drug concentrations: 1, 1.5, and 2 MAC/EC50, or specifically, at either 2, 3, and 4% end-tidal sevoflurane (n = 8), or 6, 9, and 12 [mu]g/ml plasma concentration of propofol (n = 8). Rocuronium was used for muscle relaxation.

Results: Both drugs decreased the bispectral index and blood pressure dose-dependently. Comparison between adjacent levels showed that sevoflurane initially (0 vs. 1 MAC) reduced absolute rCBF by 36-53% in all areas, then (1 vs. 1.5 MAC) increased rCBF in the frontal cortex, thalamus, and cerebellum (7-16%), and finally (1.5 vs. 2 MAC) caused a dual effect with a 23% frontal reduction and a 38% cerebellar increase. In the propofol group, flow was also initially reduced by 62-70%, with minor further effects. In the SPM analysis of the "awake to 1 MAC/EC50" step, both anesthetic agents reduced relative rCBF in the cuneus, precuneus, posterior limbic system, and the thalamus or midbrain; additionally, propofol reduced relative rCBF in the parietal and frontal cortices.  相似文献   

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