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991.
GABAergic control of basal forebrain cholinergic neurons and memory   总被引:1,自引:0,他引:1  
The involvement of the GABAergic innervation of basal forebrain neurons in the rats' conditional visual discrimination performance was examined. Performance in such a task is based on the subjects's ability to retrieve information about response rules, and previous experiments have demonstrated that basal forebrain lesions interfere with this ability. Following the acquisition of the task, chronic guide cannulae were stereotaxically implanted into the substantia innominata of both hemispheres, and the animals were retrained. Administration of the GABAA-agonist muscimol into the substantia innominata (0, 25, 50 ng/0.5 microliters/hemisphere) dose-dependently decreased the number of correct responses, increased the number of errors of omission, increased response latency, but did not affect side bias. Systemic co-administration of the cholinesterase inhibitor physostigmine (0, 0.1, 0.2 mg/kg; i.p.) exclusively interacted with the effects of muscimol on correct responding. Specifically, physostigmine dose-dependently intensified and attenuated the muscimol-induced reduction in correct responding. Although it cannot be excluded that alternative neuronal mechanisms were involved in the mediation of the effects of muscimol and their interaction with physostigmine, these findings support previous evidence indicating that the activity of basal forebrain cholinergic neurons is controlled by a GABAergic input, and that this neuronal link is involved in mnemonic processing.  相似文献   
992.
The many challenges facing nursing educators today include meeting the regulatory agency education standards while reaching staff on a variety of shifts/schedules. This article describes a model for the development, implementation, and evaluation of required inservice education that meets this challenge. Creative teaching strategies are discussed that facilitate learning at the individual level, encourage staff participation at the unit level, and contain costs at the department level.  相似文献   
993.
The Barnes Hospital Apheresis Blood Collection and Blood Transfusion Unit is part of Barns Hospital Blood Bank. Because of its size and complexity, we report our experience which may be useful to administrators and physicians involved in the planning or management of similar services. From 1985 through 1988 we collected platelets from 1,976 different donors, the majority of which (87%) were community donors. Sixty-nine percent of 1,976 donors donated in 1988 an average of 4.9 times. Of 6,568 apheresis products collected. 1.1% were discarded because of positive screening tests and 0.7% were discarded because of outdating or presence of fibrin clot. In 1988 a total of nine cell separators were used. All donor apheresis were done with seven blood separators, and on average a separator produced an apheresis product every 4.5 worked hours. All therapeutic apheresis (338) were done on two separators. Most of them (88%) were performed during work hours. In 1988 donor and therapeutic apheresis were done by 17 1/2 full-time employees (FTEs) during work hours. Considering the Workload Unit Value per procedure given by the College of American Pathologists (CAP) and that each FTE worked 1,864 hours per year, the worked hour productivity for donor and therapeutic apheresis was 78.2%. Blood collections, therapeutic bleeds, and outpatient transfusions (1,127, 114 and 1,745 respectively) were accomplished by two FTEs, for a worked hour productivity of 35.5%. Because 95.1% of total worked units was produced by efficient donor and therapeutic apheresis activities, overall efficiency remained high at 73.8%.  相似文献   
994.
995.
A combined LC/RIA procedure is described for the selective determination of dexamethasone (DEX) and its prodrug dexamethasone-21-isonicotinate (DIN) in plasma. The low affinity of the employed dexamethasone antiserum for DIN (cross-reactivity less than 0.5%) allowed the direct determination of DEX in plasma extracts. For the determination of DIN, both substances of interest were separated by LC, the DIN containing fraction was collected, hydrolysed and the generated DEX was consequently assayed by radioimmunoassay. The assay detection limits were 0.1 ng ml-1 for DEX and 0.75 ng ml-1 for DIN. For both substances, inter- and intra-day variabilities (RSDs) were 6 and 12%, respectively.  相似文献   
996.
The working clothes and individual protective devices recommended by the industrial Rules for the production of ampicillin trihydrate and its medicinal derivatives such as natrium salt ampicillin, do not provide adequate protection of the skin and respiratory mucous from antibiotic contamination. The use of the overalls in combination with the pressurized helmet (designed and produced at the 'Sintez' enterprise) which provided air supply for breathing and, partially, under the overalls, significantly decreased contamination of the body. At the stages of manual handling of the finished products, adequate protection was attained by using the protective paste produced at the 'Altaivitamine' enterprise.  相似文献   
997.
PURPOSE: This study was designed to assess pelvic bone temperature during typical treatment regimens of transurethral ultrasound thermal ablation of the prostate to establish guidelines for limiting bone heating. METHODS: Treatment with transurethral planar, curvilinear, and sectored tubular applicators was simulated using an acoustic and biothermal pelvic model that accommodates applicator sweeping, boundary temperature control, and changes in perfusion and attenuation with thermal dose to more accurately model ultrasound energy penetration. The effects of various parameters including power and frequency (5-10 MHz) on bone heating were assessed for a range of prostate cross-sections (3-5 cm) and bone distances (1-3 cm). RESULTS: All devices can produce significant bone heating (temperatures >50 degrees C, thermal dose >240 EM(43 degrees C)) without optimization of applied frequency or power for bone <3 cm from the prostate boundary. In small glands ( approximately 3 cm) increasing operating frequency of curvilinear and planar devices can increase bone temperatures, whereas the tubular applicator can be used at 10 MHz to avoid likely bone damage. In larger prostates (4-5 cm wide) increasing frequency reduces bone heating but can substantially increase treatment time. Lowering power can reduce bone temperature but may increase thermal dose by increasing treatment duration. All applicators can be used to treat glands 4-5 cm with limited bone heating by selecting appropriate power and frequency. CONCLUSIONS: Pubic bone heating during ultrasound thermal therapy of the prostate can be substantial in certain situations. Successful realization of this therapy will require patient-specific treatment planning to optimally determine power and frequency in order to minimize bone heating.  相似文献   
998.
OBJECTIVES: To determine maternal responses to detection of a minor structural variant, the choroid plexus cyst (CPC), in their fetus on prenatal ultrasound. STUDY DESIGN: We interviewed 34 pregnant women with an isolated CPC detected on mid-pregnancy ultrasound about their objective experience at diagnosis, emotional response and subsequent reactions. Audiotaped, transcribed responses were evaluated by two independent raters and analyzed qualitatively and quantitatively. RESULTS: All women reported negative emotional responses including shock, distress, fear and decreased attachment, despite counseling by 82% of providers that the CPC was probably benign. Three women underwent amniocentesis purely for reassurance after CPC detection. Most (79%) sought information beyond what their physician provided, frequently on the internet. One half of women reported that intense negative responses were temporary. However, weeks after diagnosis, 62% continued to believe that the CPC presented some danger to their baby. CONCLUSIONS: Detection of CPC prenatally can evoke profound, negative maternal emotional responses despite accurate provider counseling. Practitioners should consider these responses when counseling parents about these and other structural variants of unclear functional significance.  相似文献   
999.
1000.
Early defibrillation along with well performed basic life support (BLS) after cardiac arrest, due to ventricular fibrillation is the gold standard for increasing patients survival. Within Germany there are two standardized schemes for the training of first responders as well as of paramedics, emergency medical technicians etc.; however, the use of public access defibrillation (PAD) is highly variable between localities. Results from the USA as well as from Germany indicate approaches to life-saving issues which need addressing. The paper by Caffrey reveals high regional efficiency for PAD along with BLS, while two German studies show the value of lay individuals in BLS. Zipes (USA) study shows that death due to cardiac arrest occurs at the patient’s home in more than 70%. Two recent, standardized US trials cast doubt on the efficacy of broadly deployed BLS-training programs for lay persons, preferring PAD and BLS training carried out strictly in accordance with the risk-ratio, for instance, of the people near to the first responders. Taking this into account, social insurance for occupational accidents offer qualified first responder training for more than 43 million employees (about half of the Germany population) in more than 3 million companies. It is necessary to find a synthesis between socio-economic demands on the one hand and ethical principles on the other for the emergency medicine network.  相似文献   
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