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101.
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103.
Hearing in domestic pigs (Sus scrofa) and goats (Capra hircus)   总被引:1,自引:0,他引:1  
Behavioral audiograms were determined for three pigs and two goats. The hearing of the pigs ranged from 42 Hz to 40.5 kHz with a region of best sensitivity from 250 Hz to 16 kHz. Hearing in goats ranged from 78 Hz to 37 kHz with a well-defined point of best sensitivity at 2 kHz. Because these animals are unable to localize high-frequency tones, it seems unlikely that selective pressure to use the interaural spectral-difference cue for sound localization is behind their high-frequency hearing. Instead, we suggest that these and other hoofed mammals evolved high-frequency hearing in order to use monaural locus cues which prevent front/back locus reversals.  相似文献   
104.
Various possible risk factors for postlumbar puncture (and postiohexol-myelographic) headache and associated side effects were analysed. Headache and nausea occurred significantly more often in patients without clinical findings than in those with findings. We found significantly different incidences of severe headache and nausea between diagnostic subgroups after a lumbar puncture. The greatest headache incidence was found in patients without a definite neurological diagnosis, while nausea occurred most frequently in patients with various painful disorders. Following iohexol myelography, nausea occurred most often in patients who had a history of previous mental symptoms and in patients with a history of previous headache disorders. Mental symptoms were more frequently reported in patients who also had experienced mental symptoms previously. The relationship between side effects and negative clinical findings was stronger than the relationship between side effects and previous mental symptoms.  相似文献   
105.
PURPOSE: To determine the effect of advance care education provided to patients enrolled in cardiovascular rehabilitation (CVR) programs and assess patients' acceptance of the educational program. METHODS: In a multicenter, prospective, randomized study, the authors administered two questionnaires 6 months apart to 284 patients enrolled in 14 CVR programs in 11 states. An educational group (99 subjects) participated in educational programs related to advance care planning and received advance directive forms after completing the first questionnaires; 185 subjects served as controls. Primary outcomes were completion of patient-physician discussions of end-of-life issues and patient confidence that their end-of-life wishes were understood by their physicians. Secondary outcomes were completion of formal advance directives and patient acceptance of the educational program. RESULTS: Both the educational and control groups demonstrated a larger proportion of patients at the end of the study, compared with the amount at the beginning of the study, who had completed living wills, durable powers of attorney for healthcare, and discussions with their physicians about advance directives and life support care. These outcomes were not observed more commonly after the educational intervention. Neither groups gained confidence, however, that their physicians understood their end-of-life wishes. Only 8.6% of patients had a negative response to the educational program. CONCLUSIONS: Advance care education is well received by patients enrolled in CVR programs. Enrollment in CVR promotes advance care planning to a small but measurable degree CVR rehabilitation programs appear to be acceptable sites for advance care planning but further research is needed to develop effective educational interventions.  相似文献   
106.
J E Heffner  C A Zamora 《Chest》1990,97(2):447-452
This study was designed to determine if clinical features apparent after seven days of mechanical ventilation predict long-term intubation beyond 14 days and subsequent need for tracheotomy in patients with ARDS. Twenty-four patients were entered into the study. Group 1 patients were successfully extubated in less than or equal to 14 days after onset of ARDS and group 2 patients remained intubated greater than 14 days. On day 7 of ARDS, group 1 had a higher PaO2/PAO2 ratio, a lower PEEP requirement, less severe chest radiographic abnormalities and a greater likelihood of an improved radiograph from the baseline study. None of group 1 and 11 group 2 patients eventually underwent tracheotomy. Clinical features apparent after seven days of mechanical ventilation in patients with ARDS suggest the likelihood of prolonged intubation beyond 14 days and eventual tracheotomy. Recognition of these features may allow more timely conversion of endotracheal intubation to tracheotomy.  相似文献   
107.
对人流感病毒A/Udorn/72(H_3N_2)株与禽类流感病毒A/Mallard/NY/78/(H_2N_2)重组后的重组株分析表明,仅含禽类病毒的核蛋白(NP)或膜蛋白(M)的RNA片段的重组株,在松鼠猴的呼吸道繁殖是受限制的。另外。仅有禽类的RNAl和NS基因的重组株(Clone 12)在松鼠猴的气管内的繁殖也明显受限制,而只具有其中一个基因的Clone 9, Clone 2, 则限制就不明显。由此表明,禽类流感病毒的NP和M基因在宿主范围的繁殖限制中起主要作用,而RNAI和SN基因的结合,同样起着繁殖受限制作用。  相似文献   
108.
Neuromuscular involvement in patients with legionnaires' disease is common, with serum CK elevations in up to 78% of patients. A few cases have been associated with neuropathy. The mechanism of injury to the neuromuscular system is unknown, but organisms have not previously been found in nerve or muscle. We report the clinical, electrophysiologic, and pathologic findings in a patient with Legionella myositis and motor neuropathy, the first case to demonstrate direct muscle invasion by the Legionella organism.  相似文献   
109.
目的:分析普通男大学生髋、膝、踝、肩、肘各关节相对峰力矩与蹲跳高度的相关性。方法:实验于2004-11/2005-01在河北省体科所完成。①实验对象:随机抽取河北省某大学普通男生30名,年龄(21.8±0.8)岁,身高(170.67±5.48)cm,体质量(65.70±7.99)kg,测试前均从未进行过专门的肌肉力量训练,优势上、下肢均为右侧。②实验方法:从站立开始加摆臂的反向蹲跳,要求受试者上体尽可能保持前后方向稳定,从站立位开始下蹲时上肢向下加速摆臂,并迅速向上蹬伸起跳。从站立开始不加摆臂的反向蹲跳,是排除上肢对蹲跳高度的影响。从半蹲开始加摆臂的无反向蹲跳,要求半蹲的角度控制在105°,静止状态下半蹲预备后,直接进入向上的蹬伸起跳过程,不能出现在起动瞬间身体重心先小幅下移再向上的情况。每种动作做3次,每次间隔10min。③实验评估:通过爱捷图像解析系统得出蹲跳高度,取成绩最好的一次采用Biodex Ⅱ型等速测力及康复系统检测受试者各关节肌力相对峰力矩。利用多因素优势分析法得出在慢速[60(°、快速[240(°)/s])/s]状态下,髋、膝、踝、肩、肘关节相对峰力矩与蹲跳高度的相关性。结果:①从站立开始加摆臂的反向蹲跳高度与各关节相对峰力矩的关系:在慢速状态时与髋关节伸肌相对峰力矩、踝关节背屈肌相对峰力矩、膝关节伸肌相对峰力矩呈明显相关(r=0.808,0.692,0.656),在快速状态时与肘关节屈肌相对峰力矩呈明显相关(r=0.770)。②从站立开始不加摆臂的反向蹲跳高度与各关节相对峰力矩的关系:在慢速状态时与踝关节背屈肌相对峰力矩呈明显相关(=0.747),在快速状态时与膝关节屈肌相对峰力矩呈明显相关(r=0.796)。③从半蹲开始加摆臂的无反向蹲跳高r度与各关节相对峰力矩的关系:从半蹲开始加摆臂的无反向蹲跳高度,在慢速状态时与髋关节伸肌相对峰力矩、踝关节背屈肌相对峰力矩、膝关节伸肌相对峰力矩呈明显相关(r=0.774,0.762,0.712),在快速状态时与肘关节屈肌相对峰力矩呈明显相关(r=0.843)。结论:①加摆臂的反向与无反向蹲跳,髋关节伸肌相对峰力矩、肘关节屈肌相对峰力矩分别是慢速、快速状态下影响其高度的首要因素。②不加摆臂的反向蹲跳,踝关节背屈肌相对峰力矩、髋关节伸肌相对峰力矩分别是慢速、快速状态下影响其高度的首要因素。③提示发展上肢肌肉力量对蹲跳高度的提高大有益处。  相似文献   
110.
CI-943 (8-ethyl-7,8-dihydro-1,3,5-trimethyl-1H-imidazo[1,2-c] pyrazolo[3,4-e]-pyrimidine) is a novel agent that is chemically unrelated to available antipsychotics and is not a dopamine receptor antagonist. Like available antipsychotics, CI-943 reduces spontaneous locomotion in mice and rats and inhibits compulsive cage climbing induced by apomorphine in mice at doses that do not produce ataxia. However, CI-943 enhances rather than inhibits the locomotor stimulant effects of d-amphetamine in mice and rats. Unlike dopamine antagonists, CI-943 does not affect stereotypy caused by apomorphine or amphetamine in rats. CI-943 displays an antipsychotic-like profile in conditioned avoidance tests, inhibiting one-way avoidance in rats at doses that do not impair escape and inhibiting continuous avoidance in rats and squirrel monkeys at doses that do not impair shock termination responding. Although high doses of CI-943 produce dystonic movements in haloperidol-sensitized monkeys, CI-943 differs from dopamine antagonists that produce extrapyramidal dysfunction in humans in that doses of CI-943 that are sufficient to inhibit avoidance responding in monkeys do not produce extrapyramidal dysfunction. Unlike dopamine antagonists that produce tardive dyskinesia, CI-943 administered repeatedly at high doses does not produce behavioral supersensitivity to dopamine agonists in rats. These results demonstrate that CI-943 resembles available antipsychotics in some preclinical behavioral tests commonly used to predict antipsychotic efficacy but differs from dopamine antagonists in tests predictive of dopamine receptor antagonism and antipsychotic-induced neurological dysfunction.  相似文献   
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