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51.
Previous studies demonstrating a critical role of the hippocampus during trace eye-blink conditioning have focused primarily upon the dorsal portion of the structure. However, evidence suggests that a functional differentiation exists along the septotemporal axis of the hippocampus. In the present study, the activity of 2588 single cornu ammonis region 1 pyramidal neurons of the dorsal hippocampus and ventral hippocampus were recorded during trace and pseudo-eye-blink conditioning of the rabbit. Learning-related increases in dorsal hippocampus neuron firing rates were observed immediately prior to behavioral criterion, and increased over the course of training. Activation of dorsal hippocampus neurons during trace conditioning was also greater than that of ventral hippocampus neurons, including during the trace interval, in well-trained animals. An unexpected difference in the patterns of learning-related activity between hemispheres was also observed. Neurons of the dorsal hippocampus ipsilateral and contralateral to the trained eye, exhibiting significant increases in firing rate [rate increasing neurons], demonstrated the greatest magnitude of activation early and late in training, respectively. Rate increasing neurons of the dorsal hippocampus also exhibited a greater diversity of response profiles, with 69% of dorsal hippocampus rate increasing neurons exhibiting significant increases in firing rate during the conditioned stimulus and/or trace intervals, compared with only 8% of ventral hippocampus rate increasing neurons (the remainder of which were significantly responsive during only the unconditioned stimulus and/or post-unconditioned stimulus intervals). Only modest learning-related activation of ventral hippocampus neurons was observed, reflected as an increase in conditioning stimulus-elicited rate increasing neuron response magnitudes over the course of training. No differences in firing rate between dorsal hippocampus and ventral hippocampus neurons during a 1-day pre-training habituation session were observed. Thus, dorsal hippocampus activation is more robust, suggesting a more substantial role for these neurons in the processing of temporal information during trace eye-blink conditioning.  相似文献   
52.
Over the past several years, funding for biodefense research has increased dramatically, leading to the possibility of increased laboratory-acquired infections with potential bioterrorism agents. The Special Immunizations Program at United States Army Medical Research Institute of Infectious Diseases reviewed its policy and management of potential occupational exposures (1989-2002) to assess guidelines for determining the risk of exposure and disease and to determine criteria for initiating postexposure prophylaxis (PEP). Initiating antibiotic PEP was based primarily on exposure risk but was also influenced by vaccination status and agent virulence. PEP was given to nearly all moderate- and high-risk bacterial exposures, regardless of vaccination status, to most unvaccinated and subsets of vaccinated minimal-risk exposures, but generally not to negligible-risk exposures. Algorithms for evaluating and managing potential exposures are presented to provide guidance to other agencies as they begin to work with these agents.  相似文献   
53.
Current CDC guidance for the disinfection of gloved hands during the doffing of personal protective equipment (PPE) following the care of a patient with Ebola recommends for multiple applications of alcohol-based hand rub (ABHR) on medical exam gloves. To evaluate possible effects of ABHR applications on glove integrity, thirteen brands of nitrile and latex medical exam gloves from five manufacturers and two different ABHRs were included in this study. A pair of gloves were worn by a test operator and the outside surfaces of the gloves were separately treated with an ABHR for 1–6 applications. Tensile strength and ultimate elongation of the gloves without any ABHR treatments (control gloves) and gloves after 1–6 ABHR applications were measured based on the ASTM D412 standard method. In general, tensile strength decreased with each ABHR application. ABHRs had more effect on the tensile strength of the tested nitrile than latex gloves, while ethanol-based ABHR (EBHR) resulted in lesser changes in tensile strength compared to isopropanol-based ABHR (IBHR). The results show that multiple EBHR applications on the latex gloves and some of the nitrile gloves tested should be safe for Ebola PPE doffing based on the CDC guidance. Appropriate hospital staff practice using ABHR treatment and doffing gloves is recommended to become more familiar with changes in glove properties.  相似文献   
54.
Seventeen cases of variations of the intrahepatic portal venous system were investigated with use of duplex and color Doppler ultrasound (US). Seven cases involved absence of the horizontal segment of the left portal vein, with portal supply to the left lobe arising from the right lobe. The 10 remaining cases involved variations of intrahepatic portal branching resulting from absence of the right portal vein, taking four patterns. It is thought that these findings represent variants of normal. These variants are important in two settings: in planning hepatic surgery and in the differential diagnosis of chronic portal vein thrombosis.  相似文献   
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Evaluation of amniotic fluid in preterm labor with intact membranes   总被引:3,自引:0,他引:3  
Amniotic fluid was obtained from 35 pregnant women in preterm labor with intact membranes. Their gestational ages ranged from 24 to 34 weeks. Bacteria were detected in only 1 (3%) of the 35 amniotic fluid samples. The anaerobic culture grew Bacteroides corrodens and Fusobacterium nucleatum. The L/S ratio was greater than 4.0 in six patients (17%), 2.5-4.0 in two (6%) and less than 2.5 in 23 (66%); the quantity of fluid was inadequate for L/S analysis in four (11%). None of the 35 newborns developed evidence of infection in the neonatal period. Only two women (6%) were febrile postpartum, and none experienced a prolonged hospital stay. Seven (20%) of the infants developed respiratory distress syndrome. Five (14%) developed hyaline membrane disease, and two (6%) had transient tachypnea of the newborn. Intrauterine infection may play a lesser role in preterm labor with intact membranes than previously postulated. Amniocentesis may provide useful information for directing management by permitting one to assess fetal pulmonary maturity and the presence of meconium.  相似文献   
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58.
It was recently demonstrated that the yeast homologue of phosphatidylinositol 4-kinasebeta PIK1 is directly associated with frq1, the yeast homologue of mammalian neuronal calcium sensor-1 (NCS-1) (Hendricks et al., [1999] Nat. Cell Biol. 1:234- 241). This was a novel finding and suggests that a calcium binding protein activates and regulates PtdIns 4-kinasebeta. This finding had not been shown in mammalian cells and both PtdIns 4-kinasebeta and NCS-1 have been shown to have important roles in the regulation of exocytotic release associated with neurotransmission. The aims of this study were to determine if PtdIns 4-kinasebeta and NCS-1 directly associate in mammalian neural tissues. We show that the immunostaining pattern for PtdIns 4-kinasebeta and NCS-1 is co-localized throughout the neurites of newborn cultured dorsal root ganglia (DRG) neurons but not in E13 DRG neurons. We then provide biochemical evidence that PtdIns 4-kinasebeta may not be in physical association with NCS-1 in mammalian nervous tissue unlike that previously reported in yeast.  相似文献   
59.
This study investigated the experience and perceptions of Georgia certified nurse‐midwives about waterbirth and their level of support for establishing waterbirth in their work setting. A survey was distributed to a convenience sample of 119 certified nurse‐midwives from the American College of Nurse Midwives, Georgia chapter; 45% of those surveyed responded. The majority of midwives had some exposure to waterbirth through self‐education or through clinical practice. More than half supported the incorporation of waterbirth in their workplace setting. Maternal relaxation and reduced use of analgesia were perceived as the greatest benefit of waterbirth. Of 11 items related to disadvantages of waterbirth, certified nurse‐midwives were moderately to severely concerned about none. The most concerning factors, with a mean of 2.4 to 2.5 on a scale of 1 (no worry) to 5 (severe worry), were maintenance of water temperature, physical stress on the midwife, and inability to see the perineum. Midwives' support for waterbirth focused mostly on the perceived benefits to the mother with little worry about the risks.  相似文献   
60.
The problem considered is whether self‐reported substance use can be used in the estimation of recidivism risk among youths placed in secure care. The Secure Care Psychosocial Screening (SECAPS) and offending records of 447 youths admitted to detention centres in South Australia were examined. The target outcome was any new offending within 6 months of release. Use of a psychoactive substance at the time of committing the most recent offence was not a significant predictor of subsequent offending, nor was acknowledging having a problem with drug or alcohol use. In relation to the recent use of alcohol, marijuana, hallucinogens, sedatives/hypnotics, narcotics, stimulants and inhalants, only the use of alcohol and inhalants appeared to have significant relationships with recidivism. While the relationships were too small to permit using these items on their own to estimate re‐offending risk, recent alcohol and inhalant use could be included as part of a broader recidivism risk assessment.  相似文献   
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