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21.
C. K. Peck J. A. Baro 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1997,113(2):291-302
Neurons in the rostral superior colliculus (SC) of alert cats exhibit quasi-sustained discharge patterns related to the fixation
of visual targets. Because some SC neurons also respond to auditory stimuli, we investigated whether there is a population
of neurons in the rostral SC which is active in relation to fixation of both auditory and visual targets. We identified cells
which were active with visual fixation and which continued to discharge if the fixation stimulus was briefly extinguished.
The population of neurons exhibited similar discharge characteristics when the fixation stimulus was auditory. Few neurons
were significantly more active during fixation of visual targets than during fixation of auditory targets. Most fixation neurons
showed a diminished discharge rate during spontaneous (self-generated) saccadic eye movements away from a visual fixation
stimulus, regardless of the direction of the saccade. this diminished discharge rate (or pause) typically began, on average,
12.2 ms before saccade onset and the duration of the pause was Ionger than the duration of the saccade. These observations
are consistent with the hypothesis that increased discharge of these neurons is related to active fixation and that reductions
in their activity are important for the generation of saccades. However, the lack of a precise relationship between pause
duration and saccade duration implies that these neurons would be unlikely to project directly to the saccadic burst generator.
The mean interval from the beginning of the pauses of fixation neurons to be beginning of the saccades away from fixation
targets is also shorter than has been found in brainstem omnipause neurons. By analogy with the concept of a receptive field,
agaze position error field depicts the range of gaze position error for which a cell is active. Although fixation neurons appear to encode the magnitude
and direction of the error between visual targets and the visual axis, visual error fields at the end of fixating eye movements
were significantly larger than those at stimulus onset. For auditory stimuli, this difference was not significant. These observations
are compatible with a number of recent experiments indicating that neural signals of eye position are damped or delayed with
respect to current eye position. 相似文献
22.
Humphreys-Beher MG Brayer J Yamachika S Peck AB Jonsson R 《Scandinavian journal of immunology》1999,49(1):07-10
Sjögren's syndrome is characterized by dryness of the eyes and the mouth due to mononuclear cell infiltration of the lacrimal and salivary glands. The aetiology is unknown but autoimmunity is considered to play a significant role in the pathogenesis. Recent studies have focused on the fact that tear and salivary flow involves an entire functional system that includes the mucosal surfaces with adnexes (the site of inflammation), efferent nerve signals sent to the midbrain (lacrimal and salivary response region), and afferent neural signals from the brain to the acinar/ductal epithelial structures in the gland. Mononuclear cell infiltration in exocrine glands can lead to glandular destruction, suggested to be mediated through apoptosis. However, the functional impairment of exocrine glands could be regulated by cytokines and/or antibodies against the muscarinic M3 receptor by inhibiting the neural stimulation of the residual glands. This review discusses the possibility that the pathogenesis of Sjögren's syndrome comprises aberrant immune-mediated neuro-hormonal events. 相似文献
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The MARSEPH program, named for the two principal program collaborators--the Marillac Social Center and Saint Joseph Health Centers and Hospital--provides life and work skills to homeless men who visit a day shelter operated by the Marillac Social Center. Participants gain work experience at Saint Joseph. One of the most important aspects of the MARSEPH program is the removal of obstacles to the newly employed. Each MARSEPH participant receives housing assistance, a uniform, transportation to Saint Joseph Health Centers and Hospital, and a meal pass to the hospital's cafeteria. Through this assistance, the men can get off the streets, get to their jobs, be nourished, and look presentable. The MARSEPH program carefully monitors each participant's progress, to ensure his success. Case workers meet weekly with the men to discuss problems and concerns. Every week case workers also visit each participant's residence to monitor his living conditions and offer emotional support. At the end of the six-month training program, MARSEPH helps graduates find employment. 相似文献
27.
447C88 (N-Heptyl-N-(2,4 difluoro-4-6-(2(-4-(2,2 dimethylpropyl)phenyl)ethyl)phenyl)urea) is an inhibitor of human microsomal AcylCoA:Cholesterol acyltransferase (ACAT) with an IC50 of 10.2 ng·ml–1 (23 nM). It is poorly absorbed but 5 mg·kg–1·day–1 completely abolishes the rise in plasma cholesterol in cholesterol-fed rats.In this study, twelve healthy, male volunteers received single, oral doses of 25, 50, 100, 200, 400 and 800 mg of 447C88 (n+8) or placebo (n+4) with food in a double-blind study with at least a week between occasions. The 400 mg dose was repeated after an overnight fast. Subsequently, fourteen different volunteers received a single 200 mg dose of 447C88 (n+8) or placebo (n+6) with food and, a week later, the same dose twice daily for 10 days; all doses were given with food.All doses were well tolerated with no significant changes in vital signs, full blood counts or plasma biochemical profiles. Plasma concentrations of 447C88 were unquantifiable after the fasting dose and low after all other doses. Mean Cmax and AUC were 1.8 ng·ml–1 and 9.0 ng·ml–1·h after 200 mg rising to 5.4 ng·ml–1 and 23.8 ng·ml–1·h respectively after 800 mg; t1/2 was 1.3 to 5.2 h. After 10 days dosing, plasma 447C88 concentrations were higher in the evening than the morning probably due to administration of the evening dose with more food. There were no significant changes in plasma triglcerides or total, LDL- or HDL-cholesterol after dosing with 447C88. 相似文献
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Eighty four out of 2151 militancy trauma patients sustained severe maxillofacial injury from Jan 1990 to March 1993. The resuscitation, stabilisation and intensive care of these patients was based on management priorities of primary resuscitation, care of airway, management of haemodynamics, oxygenation and monitoring. Anaesthesia was administered in a situation when the airway was likely to be compromised and the patients were critically sick. Initial ventilation and oxygenation was the most difficult and could be achieved with satisfactory seal around the face mask by applying water-soaked guaze pieces around the mouth and nose to “fill-in” the defects. Tracheal intubation could be accomplished with intravenous sedation by an experienced anaesthesiologist. Dental occlusion and wiring necessiated the placement of nasotracheal tube for 48-72 hours after surgery.KEY WORDS: Trauma, Maxillofacial injury, Trauma anesthesia, Anaesthesia and critical care 相似文献
30.
One hundred patients undergoing abdominal surgery were included in this prospective study. The role of local application of Betadine, use of synthetic sutures, and use of low pressure subcutaneous suction drainage were evaluated in preventing post-operative wound infection. The infection rate was 15 per cent with Betadine, 15.4 per cent with prolene, 20 per cent with subcutaneous suction drainage and 30.8 per cent in the control group.KEY WORDS: Surgical wound infection, Betadine, Sutures, Infection control 相似文献