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31.
We report on a female newborn with deletion of the short arm of the chromosome 18 (del 18p) and hypoplastic left heart syndrome (HLHS) with intact atrial septum. Several forms of congenital heart disease (CHD) are found in 10% of patients with this chromosomal abnormality, although HLHS has not been reported yet. Interesting coronary artery anomalies, as well as the presence of pulmonary lymphangiectasia, were found in our patient and were contributors to her fatal outcome. Del 18 p must be considered when evaluating a patient with characteristic phenotypical anomalies and HLHS with intact atrial septum.  相似文献   
32.
Neuroleptic-induced akathisia (NIA) is motor restlessness caused by dopamine receptor blocking antipsychotic agents. Nine patients with NIA and 11 patients with idiopathic restless legs syndrome (RLS) were studied polysomnographically. The sleep disturbances were milder in NIA than idiopathic RLS but increased numbers of awakenings and decreased sleep efficiencies were common to both groups. In addition, RLS patients demonstrated prolonged sleep latencies. Periodic movements in sleep (PMS) were present in only 5 of 9 patients with NIA but in all 11 patients with idiopathic RLS. In no NIA patient did we see the multiple, large amplitude, violent, resting myoclonic jerks of the legs that we saw during wakefulness in some of our more severe cases of idiopathic RLS. NIA patients tended to experience inner restlessness and idiopathic RLS patients tended to experience leg paresthesias as an antecedent to motor restlessness. Idiopathic RLS patients had symptoms that were worse at night and in repose far more frequently than patients with NIA. NIA and idiopathic RLS have similarities and differences. Because both NIA and idiopathic RLS are characterized by motor restlessness and sleep disturbances, the pharmacodynamics of antipsychotic medications may give clues as to both the cause and treatment of idiopathic RLS.  相似文献   
33.
The interaction of mononuclear phagocytes with Cryptococcus neoformans was examined in vitro and in vivo using ultrastructural techniques. Immune serum roughens the surface of the yeast and in the first 2 hr, increases the number of organisms attaching to the macrophage surface, as well as the number of contacts between individual yeasts and the phagocyte. Contact is established by means of thin filopodia and cytoplasmic flaps. During the next few days the macrophages increase in size, and, by intimate apposition of their contiguous cell surfaces, a cellular barrier surrounds the now enclosed yeast. These events are accompanied by thinning of fungal capsule, degradation of the enclosed cryptococcus, and the formation of macrophage polykaryons. Electron cytochemical techniques for peroxidase reveal that these multinucleated cells are formed predominantly by the fusion of stimulated macrophages. Destruction of the enclosed yeast probably results from the secretion of various agents by the surrounding cells.  相似文献   
34.
Reported two studies that examined the efficacy of the Personality Research Form (PRF) as an outcome measure for interventions designed to increase social competence. In the first study (N = 83), the degree to which PRF scales can predict criteria frequently used in social skills training outcome research was examined, and the PRF was shown to be sensitive to such criteria. The second study (N = 24) assessed the relative degree to which the PRF scales and more frequently used outcome measures, including the above criteria, are affected by factors non-specific to social skills training interventions (suggestion for improvement). While three PRF scales were affected significantly, demand effects were much more pervasive on the other measures, which suggests that those measures can be used to obtain valid estimates of treatment effects only when experimental control of non-specific effects is possible. Two PRF scales, Affiliation and Exhibition, were shown to be both sensitive to criteria and resistant to demand effects, and as such may be useful as outcome measures in non-controlled clinical settings.  相似文献   
35.
The diffusing capacity of the lung for carbon monoxide (DLCO) decreases to below the pre-exercise value in the hours following a bout of intense exercise. Two mechanisms have been proposed: (1) development of pulmonary oedema and (2) redistribution of central blood volume to peripheral muscles causing a reduction in pulmonary capillary blood volume (Vc). In the present study DLCO, Vc and the membrane diffusing capacity (Dm) were measured in nine healthy females using a rebreathing method, in contrast to the single breath technique employed in previous studies. DLCO, Vc and Dm were measured before and at 1, 2, 3, 16 and 24 h following maximal treadmill exercise. Compared with pre-exercise values, DLCO was depressed by up to 8.9 (3.0)% (P<0.05) for the first 3 h following exercise, but had returned to pre-exercise values by 16 h post-exercise. Vc fell by 21.2 (4.1)% (P<0.05) at 3 h post-exercise, but at the same time Dm increased by 14.7 (9.1)%. It was concluded that: (1) the increase in Dm made it unlikely that the fall in DLCO was due to interstitial oedema and injury to the blood gas barrier; (2) on the other hand, the reduction in DLCO following exercise was consistent with a redistribution of blood away from the lungs; and (3) the trend for Dm and Vc to reciprocate one another indicates a situation in which a fall in Vc nevertheless promotes gas transfer at the respiratory membrane. It is suggested that this effect is brought about by the reorientation of red blood cells within the pulmonary capillaries following exercise.  相似文献   
36.
Mechanical, chemical, or electrical stimulation of the tail elicits a short-latency (less than 1 s) tail-withdrawal reflex that is graded with the intensity of the stimulus. The tail-withdrawal reflex is not elicited by stimulation of parts of the body outside of the tail region. Mechanoafferent neurons innervating the tail are located in a small subcluster within a large, homogeneous group of medium-size (40-80 micron) cells on the ventrocaudal (VC) surface of each pleural ganglion. The tail sensory neurons within this large VC cluster are activated by tactile pressure or by electrical stimulation of discrete regions of the tail. They adapt slowly to maintained stimulation and sometimes respond to stimulus offset as well. Both mechanical and electrical stimuli produce responses that are graded with the intensity of the stimulus. Cells in the VC cluster appear to be primary mechanoreceptors because they have axons in peripheral nerves (including nerves innervating the tail), they exhibit action potentials lacking prepotentials in response to tactile stimulation, and these action potentials are still produced by cutaneous stimulation when peripheral and central chemical synaptic transmission is blocked. Stimulation of fields all over the body surface evokes synaptically mediated hyperpolarizing responses in individual mechanoafferent neurons that may represent afferent inhibition. Hyperpolarizing responses lasting many seconds can be produced by brief cutaneous stimuli. The mechanoafferent neurons innervating the tail region make strong monosynaptic connections to tail motor neurons in the ipsilateral pedal ganglion, and through these connections this subpopulation of the VC neurons appears to make a substantial contribution to the short-latency tail-withdrawal reflex. In addition, the combined excitatory receptive fields of these mechanoafferents match the excitatory receptive field of the tail-withdrawal reflex. Mechanoafferent neurons in the VC cluster that have receptive fields on other parts of the body (outside the excitatory receptive field of the tail-withdrawal reflex) have not been observed to make monosynaptic connections to the tail motor neurons. The neurons innervating the tail are reliably found in a discrete region within the larger VC cluster. In addition to this gross somatotopic organization, there is evidence of a finer level of somatotopic organization between the position of the excitatory receptive field on the tail and the position of the cell soma in the tail subcluster.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
37.
Journal of Community Health - While human papilloma virus (HPV) vaccinations and Pap smear screenings are known to improve the survival rates and incidence of cervical cancer, refugee populations...  相似文献   
38.
Forty patients with acute onset renal colic were studied using technetium-99m DTPA renal scintigraphy. Thirty-two were found to have varying degrees of obstruction. In the obstructed group the level was determined by the scan alone in 24 of 32 cases (75%). When the analysis included an abdominal radiograph, the level of obstruction was ascertained in 29 of 32 cases (91%). A delayed nephrogram, as evidenced by an "empty renal pelvis sign" at 5 minutes, was observed in all but one of the cases of obstruction (97%). Delayed clearance of activity from the pyelocalyceal system or ureter was also seen in 97%. In all cases of obstruction either one or both of these signs were observed. However, delayed clearance was found to be a nonspecific finding and was noted in 25% of nonobstructed cases. The finding of the "empty renal pelvis sign" at 5 minutes was found to be specific and was not seen in the nonobstructed group. The authors conclude that radionuclide renal scanning is an effective method for evaluating selected patients with suspected renal colic.  相似文献   
39.
Social relatedness and autism: current research, issues, directions   总被引:1,自引:0,他引:1  
Social relatedness has recently become a primary focus of investigators in the field of autism. This shift to regarding disturbances in social relatedness as one of the defining manifestations of the disorder marks the movement of research on autistic disorder back to its origins, when Kanner first noted the "social and affective" symptoms of autism as pathognomonic. Currently, social impairment in autism is viewed as more pervasively characteristic of the disorder than any other single symptom. Further, there has been a recent proliferation of research designed to document the nature of social deficit in autism, and whether it is primarily affective, communicative, or cognitive in nature, or involves some combination of these three variables. This review summarizes recent research focusing on social relatedness in autism and discusses the implications of these findings.  相似文献   
40.
The Relationship between Muscle Function and Ankle Stability   总被引:6,自引:0,他引:6  
The purpose of this investigation was to document the degree of weakness present in the medial and lateral muscle groups of individuals with chronically unstable ankles. Peak isometric and isokinetic torque measurements were collected bilaterally during the motion of inversion-eversion from 33 subjects, ages 17 to 54, reporting unilateral chronic lateral instability. Values were then compared between the involved and uninvolved sides. A modified Romberg test was also performed bilaterally to determine gross balance differences between the involved and uninvolved lower extremities. No significant difference in muscle strength was documented either isometrically or isokinetically, but balance differences were found between the two extremities in a majority of subjects. The findings suggest that muscular weakness is not a major contributing factor to the chronically unstable ankle. The findings do support the presence of proprioceptive deficits associated with this condition. Based on the results, proprioceptive activities should be a primary consideration in management of the chronically unstable ankle. J Orthop Sports Phys Ther 1990;11(12):605-611.  相似文献   
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