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111.
The eastern gray squirrel (Sciurus carolinensis) often serves as a model organism for investigations of wildlife ecology. The authors developed 11 polymorphic microsatellite markers to facilitate future research questions. The number of alleles per locus ranged from three to ten and observed heterozygosities ranged from 0.143 to 0.786. Interspecific screening revealed that several loci were polymorphic in Sciurus niger (eight loci) and Tamiasciurus hudsonicus (four loci). These markers will aid in investigations of movements, social structure and mating tactics of eastern gray squirrel populations.  相似文献   
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Introduction: The prevalence of maternal group-B-streptococcus (GBS) colonization and risk factors (RFs) for neonatal early-onset disease (EOD) in Europe are poorly defined. Large-scale information concerning adherence to recommendations for preventing GBS-EOD are lacking.

Materials and methods: This was a 3-month retrospective area-based study including all regional deliveries ≥35 weeks' gestation (in 2012). The sensitivity, specificity, positive and negative predictive values, odds ratio and receiver operating characteristic (ROC) curve for intrapartum antibiotic prophylaxis (IAP) among full-term and preterm deliveries and prolonged membrane rupture (PROM) were calculated.

Results: Among 7133 women, 259 (3.6%) were preterm (35–36 weeks' gestation). Full-term women were 6874, and 876 (12.7%) had at least 1?RF. Most women (6495) had prenatal screening and 21.4% (1390) were GBS positive.

IAP was given to 2369 (33.2%) women (preterm, n?=?166; full term, n?=?2203). Compared to full-term, preterm women were less likely to receive IAP when indicated (73.2% versus 90.3%, p?Conclusions: Large-scale prenatal screening and IAP are feasible. Women delivering preterm are less likely to receive IAP when indicated. Most unnecessary antibiotics are given in cases of PROM.  相似文献   
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The human mirror system has been the subject of much research over the past two decades, but little is known about the timecourse of mirror responses. In addition, it is unclear whether mirror and counter-mirror effects follow the same timecourse. We used single-pulse transcranial magnetic stimulation to investigate the timecourse of mirror and counter-mirror responses in the human brain. Experiment 1 demonstrated that mirror responses can be measured from around 200 ms after observed action onset. Experiment 2 demonstrated significant effects of counter-mirror sensorimotor training at all timepoints at which a mirror response was found in Experiment 1 (i.e. from 200 ms onward), indicating that mirror and counter-mirror responses follow the same timecourse. By suggesting similarly direct routes for mirror and counter-mirror responses, these results support the associative account of mirror neuron origins whereby mirror responses arise as a result of correlated sensorimotor experience during development. More generally, they contribute to theorizing regarding mirror neuron function by providing some constraints on how quickly mirror responses can influence social cognition.  相似文献   
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Human spermatozoa may chemotactically find out the egg by following an increasing gradient of attractant molecules. Although human spermatozoa have been observed to show several of the physiological characteristics of chemotaxis, the chemotactic pattern of movement has not been easy to describe. However, it is apparent that chemotactic cells may be identified while returning to the attractant source. This study characterizes the pattern of movement of human spermatozoa during chemotactic re-orientation towards a progesterone source, which is a physiological attractant candidate. By means of videomicroscopy and image analysis, a chemotactic pattern of movement was identified as the spermatozoon returned towards the source of a chemotactic concentration of progesterone (10 pmol l−1). First, as a continuation of its original path, the spermatozoon swims away from the progesterone source with linear movement and then turns back with a transitional movement that can be characterized by an increased velocity and decreased linearity. This sperm behaviour may help the spermatozoon to re-orient itself towards a progesterone source and may be used to identify the few cells that are undergoing chemotaxis at a given time.  相似文献   
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A reduction of gallbladder emptying in response to neural or hormonal stimulation has been reported in patients with diabetes mellitus. Decreased gallbladder emptying may be a key factor in the pathogenesis of gallbladder stones. Few drugs, if any, are able to stimulate gallbladder emptying. However, in a previous study we demonstrated that erythromycin, a macrolide antibiotic, stimulates gallbladder emptying and motilin release in healthy human subjects by an atropine-sensitive pathway. Therefore, the present study was designed to evaluate the effect of erythromycin on gallbladder emptying and motilin release in diabetic patients with or without cardiac autonomic neuropathy (AN). Thirteen diabetic patients, six with AN, and 10 healthy subjects were enrolled in the study protocol. Gallbladder emptying was determined by sonography after ingestion of a standard meal and during infusion of erythromycin alone or together with 6 g/kg/hr atropine. We found that 100 mg/hr erythromycin caused a significant reduction in gallbladder volume in both healthy subjects and diabetic patients. The ejection fraction (mean ±se) of 45.3±8.2% and 37.3±5.0% was similar. The presence of AN had no influence on gallbladder emptying induced by erythromycin. Basal motilin plasma levels were 111.5±14.5 pmol/liter in diabetic patients and 63.3 ±6.0 pmol/liter in healthy subjects (P<0.01). However, patients with AN had higher (130.0 ±11.9 pmol/liter) motilin plasma levels than patients without (74.0±9.4 pmol/liter,P<0.01). Erythromycin administration caused an approximately twofold increase in plasma motilin concentrations in healthy subject and patients withou AN, but did not stimulate motilin release in neuropathic patients. A negative correlation (r=–0.75,P<0.01) was found between basal plasma levels of motilin and peak of gallbladder emptying induced by erythromycin. Atropine completely inhibited the effects of erythromycin on gallbladder emptying and motilin release (P<0.001 by ANOVA). A negative correlation (r=–0.52,P<0.05) was also found between plasma glucose concentrations and peak of gallbladder emptying. Present results demonstrate that erythromycin could be used for treating alterations of gallbladder emptying in diabetic patients with or without AN.  相似文献   
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