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991.
Objectives  To assess the association between maternal parvovirus B19 infection and fetal death, birthweight and length of gestation.
Design  Case–control study.
Setting  Population based.
Population  Cases were all 281 women with fetal death within a cohort of 35 940 pregnant woxmen in Norway. The control group consisted of a random sample of 957 women with a live born child.
Method  Information on pregnancy outcome was obtained from the Medical Birth Registry of Norway. First trimester serum samples were tested for antibodies against parvovirus B19 (IgM and IgG). In seronegative women, further serum was analysed to detect seroconversion during pregnancy.
Main outcome measures  Fetal death, length of gestation and birthweight.
Results  Two of 281 (0.7%) of the women who experienced fetal death and nine of 957 (0.9%) of the controls had presence of IgM antibodies, crude odds ratio 0.8; 95% CI (0.2–3.5). In initially, seronegative women, 3.1% (2/65) with fetal death and 2.6% (8/307) with a live birth seroconverted, crude odds ratio 1.2; 95% CI (0.2–5.7). Presence of maternal parvovirus-specific IgG or IgM antibodies in the first trimester, or seroconversion during pregnancy were not associated with lower birthweight or reduced length of gestation in live born children, but was associated with low birthweight in stillborn offspring.
Conclusion  Maternal parvovirus B19 infection was not associated with fetal death in our study. Very few cases of fetal death may be attributed to maternal parvovirus B19 infection.  相似文献   
992.

Background

Genetically engineered mouse models of human cardiovascular disease provide an opportunity to understand critical pathophysiological mechanisms. Cardiovascular magnetic resonance (CMR) provides precise reproducible assessment of cardiac structure and function, but, in contrast to echocardiography, requires that the animal be immobilized during image acquisition. General anesthetic regimens yield satisfactory images, but have the potential to significantly perturb cardiac function. The purpose of this study was to assess the effects of general anesthesia and a new deep sedation regimen, respectively, on cardiac function in mice as determined by CMR, and to compare them to results obtained in mildly sedated conscious mice by echocardiography.

Results

In 6 mildly sedated normal conscious mice assessed by echo, heart rate was 615 ± 25 min-1 (mean ± SE) and left ventricular ejection fraction (LVEF) was 0.94 ± 0.01. In the CMR studies of normal mice, heart rate was slightly lower during deep sedation with morphine/midazolam (583 ± 30 min-1), but the difference was not statistically significant. General anesthesia with 1% inhaled isoflurane significantly depressed heart rate (468 ± 7 min-1, p < 0.05 vs. conscious sedation). In 6 additional mice with ischemic LV failure, trends in heart rate were similar, but not statistically significant. In normal mice, deep sedation depressed LVEF (0.79 ± 0.04, p < 0.05 compared to light sedation), but to a significantly lesser extent than general anesthesia (0.60 ± 0.04, p < 0.05 vs. deep sedation). In mice with ischemic LV failure, ejection fraction measurements were comparable when performed during light sedation, deep sedation, and general anesthesia, respectively. Contrast-to-noise ratios were similar during deep sedation and during general anesthesia, indicating comparable image quality. Left ventricular mass measurements made by CMR during deep sedation were nearly identical to those made during general anesthesia (r2 = 0.99, mean absolute difference < 4%), indicating equivalent quantitative accuracy obtained with the two methods. The imaging procedures were well-tolerated in all mice.

Conclusion

In mice with normal cardiac function, CMR during deep sedation causes significantly less depression of heart rate and ejection fraction than imaging during general anesthesia with isoflurane. In mice with heart failure, the sedation/anesthesia regimen had no clear impact on cardiac function. Deep sedation and general anesthesia produced CMR with comparable image quality and quantitative accuracy.  相似文献   
993.
Background: The effect of parecoxib, when used perioperatively or during interventional techniques, is well demonstrated in the literature. Little is known about its effects on anxiety levels before the analgesic technique application. The aim of this prospective, randomized, double‐blind, placebo‐controlled, clinical study is to investigate whether parecoxib, preemptively administrated, has an effect on anxiety levels reported prior to an epidural puncture, and if it influences the reported pain of the interventional technique itself. Material and Methods: The study protocol involved 110 patients, scheduled for epidural catheter placement for chronic pain therapy—Group I, as well as 112 patients scheduled for orthopedic operations under epidural anesthesia—Group II. Patients in each group were randomly allocated into two subgroups in relation to parecoxib/placebo administration before epidural catheter placement: Group Ia, parecoxib 40 mg i.v. (n = 54), Group Ib, placebo (n = 56), Group IIa, parecoxib 40 mg i.v. (n = 57), Group IIb, placebo (n = 55). Patients were given a self‐administered inventory to measure the anxiety level of the presurgical/preprocedural state (State‐Trait Spielberger Anxiety Inventory) and anxiety levels were recorded 1 hour before epidural puncture, 20 minutes postdosing, and 1 hour after epidural catheter placement. Anxiety levels were also measured and recorded using visual analog scale (VAS). One hour after epidural puncture, reported procedural pain was recorded (VAS). One hour and 6 hours postepidural, patients' satisfaction was also recorded, on a 4‐point scale. Results: All four subgroups were similar regarding demographic, operative/procedural data, and coexisting diseases. Preprocedural anxiety levels were significantly decreased with parecoxib administration in comparison with placebo in both groups (P < 0.05). Reported VAS regarding pain from epidural puncture was lower in Groups IA and Ib. Patients' satisfaction was greater with parecoxib in comparison with placebo. Conclusion: The levels of anxiety have been investigated in several medical procedures and early, in the study of pain. The higher the expectation of pain and the anxiety are, the higher the intensity of the pain. Parecoxib seems to exert positive influence on pain and anxiety levels of interventional procedure. Further studies are needed to elucidate the actual mechanisms that are involved.  相似文献   
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The accumulation of sequenced Francisella strains has made it increasingly apparent that the 16S rRNA gene alone is not enough to stratify the Francisella genus into precise and clinically useful classifications. Continued whole-genome sequencing of isolates will provide a larger base of knowledge for targeted approaches with broad applicability. Additionally, examination of genomic information on a case-by-case basis will help resolve outstanding questions regarding strain stratification. We report the complete genome sequence of a clinical isolate, designated here as F. novicida-like strain TCH2015, acquired from the lymph node of a 6-year-old male. Two features were atypical for F. novicida: exhibition of functional oxidase activity and additional gene content, including proposed virulence determinants. These differences, which could potentially impact virulence and clinical diagnosis, emphasize the need for more comprehensive methods to profile Francisella isolates. This study highlights the value of whole-genome sequencing, which will lead to a more robust database of environmental and clinical genomes and inform strategies to improve detection and classification of Francisella strains.  相似文献   
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To test the hypothesis that there are significant differences in the radiographic appearance of rheumatoid arthritis between men and women, the authors blindly evaluated bilateral hand and wrist radiographs in 32 men with definite rheumatoid arthritis and 32 age- and disease duration-matched women (mean age, 56.4 years; mean disease duration, 10.5 years). Radiographically, disease distribution and severity were identical in these matched groups. Superimposed osteoarthritis was frequent in both groups and related to age. Ill-defined bone proliferation was present in 13 of 64 hands in both groups. Cystic changes and well-defined erosions were present in 12 of 64 male hands and six of 64 female hands, but this difference was not statistically significant. In women, presence of cysts and bone proliferation was related to disease duration, whereas men exhibited these atypical features independent of disease duration. There was no statistically significant difference in the frequencies of typical and atypical features of rheumatoid arthritis between the two sexes, and the authors postulate that previously reported differences relate to patient selection and lack of adequate matching.  相似文献   
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