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排序方式: 共有849条查询结果,搜索用时 15 毫秒
791.
792.
793.
The effect of convergence on the vestibulo-ocular reflex and implications for perceived movement 总被引:1,自引:0,他引:1
The apparent motion of a fixated stimulus during head translation in the dark was found to depend on the magnitude of the vestibulo-ocular reflex (VOR). Absolute convergence level determines VOR magnitude and thereby influences apparent motion during head movement by determining the magnitude and direction of the pursuit effort required to maintain gaze stability. The results are discussed in terms of the biological utility of the coupling between convergence and the VOR in maintaining image stability, and the role of the pursuit eye movement system in illusory movement. 相似文献
794.
This study evaluated the use of the MacKinnon splint upon grasp skills in three children, ages 2 1/2 to 7 1/2, with spastic hemiplegia. The MacKinnon splint was sequentially introduced in a multiple baseline design across subjects. The results indicated improvement in each child's grasp of eight different, randomly presented objects, after a MacKinnon splint was provided for daily wear. 相似文献
795.
Suppression of neuropeptide Y-elicited eating by adrenalectomy or hypophysectomy: reversal with corticosterone 总被引:5,自引:0,他引:5
Neuropeptide Y (NPY) injected into the paraventricular hypothalamus (PVN) stimulates a robust eating response in the satiated rat. To examine whether the NPY-feeding system interacts with the pituitary-adrenal axis, the eating response to PVN injections of NPY (78 pmol) was tested in adult male rats before and after sham surgery, adrenalectomy (ADX), hypophysectomy (HYPX), and/or corticosterone (CORT) replacement therapy. In unoperated or sham groups, NPY elicited 5.7-8.8 g of food intake in 1 h as compared to 0.4-1.1 g for vehicle-injected animals. In ADX groups, the NPY-elicited response was reduced by 60-71%, to between 2.4 and 2.8 g. Likewise, the average response of the HYPX group was reduced by 69%, to 1.7 g. Corticosterone replacement, via subcutaneous implant of a 100 mg CORT pellet, normalized the NPY-induced feeding response in both the ADX and HYPX groups. These findings suggest that the hypothalamic NPY-feeding system is largely dependent upon circulating CORT and that no other adrenal or pituitary hormone is essential. 相似文献
796.
A Mauskop BT Altura RQ Cracco BM Altura 《Cephalalgia : an international journal of headache》1994,14(1):24-28
The entity of chronic daily headache (CDH) is well documented, but is not included in the current classification. We divided patients with CDH into groups with and without migrainous features. This division resulted in clearly distinguishable syndromes of daily migrainous headaches (DMH) and daily tension-type headaches (DTH). Family history of headaches was more common in patients with DMH. Patients in both groups had a high incidence of caffeine or drug overuse. The clinical division into DMH and DTH was supported by our finding of a higher incidence of disturbed magnesium (Mg) metabolism in patients with DMH. Of 26 patients with DMH, 8 (30.8%) had low serum ionized, but not total, Mg levels, and 16 (61.5%) had high ionized calcium/magnesium ratios. The corresponding numbers for the 22 patients with DTH were 1 (4.5%) and 8 (30.4%). These new laboratory measurements offer possible biological markers for the diagnosis of different headache syndromes. 相似文献
797.
U Leibowitz 《Electroencephalography and clinical neurophysiology》1969,26(5):515-523
798.
M R Leibowitz D P Derman R Jacobson K Stevens J Katz 《Suid-Afrikaanse tydskrif vir geneeskunde》1976,50(51):2035-2037
A study on 25 South African Black patients with chronic myelogenous leukaemia (CML), who were followed for 3 1/2 years, is reported. The Ph chromosome was found in 19 of 20 patients studied. Males predominated in a ratio of 2,5:1. Several unusual clinical features were encountered: significant lymphadenopathy, congestive cardiac failure and skin lesions. Patients with lymphadenopathy responded to busulphan therapy no differently from patients without lymphadenopathy. Nine patients had congestive cardiac failure, and in 7 of these a cause could not be found. Three untreated patients became pregnant, indicating that CML per se does not cause infertility. The haematological measurements were similar to those of previous reports; however, the marked splenomegaly suggests that South African Black patients present themselves for treatment rather late in the disease. The median survival time of 34 months is similar to that of previous reports of larger series from other parts of the world. 相似文献
799.
Three experiments investigated the feeding response of brain cannulated rats to hypothalamic injection of norepinephrine (NE), the opiate agonist morphine sulfate (MO) and the opiate antagonist naloxone (NAL). Morphine elicited feeding in a dose-dependent manner when injected into the paraventricular nucleus (PVN) of satiated rats, at doses of 0.78 to 100 nmoles, with a threshold dose of 1.56 nmoles. Naloxone, at doses of 3.13 to 200 nmoles, was injected into the PVN of food-deprived rats and was found to produce a dose-dependent suppression of feeding (threshold dose of 6.25 nmoles). Animals with brain cannulas aimed at the PVN, the perifornical hypothalamus (PFH), the dorsomedial (DMN) and ventromedial (VNM) nuclei were compared for their sensitivity to the feeding stimulatory effects of NE and MO (except in the DMN) and the feeding suppressive effects of NAL. Consistent with earlier reports, the PVN-cannulated animals exhibited a reliable increase in feeding after NE injection; the VMN cannula yielded a small feeding response, whereas the DMN and PFH were insensitive to NE. Morphine, in contrast, strongly stimulated eating after administration into PFH, as well as the PVN, apparently dissociating the NE and MO eating responses. The VMN, however, was generally unresponsive to both MO and NE. With regard to NAL's suppressive effect on feeding, the PVN and PFH, which were sensitive to MO, also exhibited responsiveness to opiate antagonism suggesting the existence in these areas of opiate receptors that modulate feeding.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
800.
R E Perkins R B Kundsin M V Pratt I Abrahamsen H M Leibowitz 《Journal of clinical microbiology》1975,1(2):147-149
The conjunctivas of 273 inflamed eyes were cultured by both aerobic and anaerobic techniques. Isolations were obtained from 267 (97.8%) of the eyes. Aerobic organisms were isolated from 237 (86.8%) of the conjunctivas. Staphylococcus aureus from 63 (23.1%) of the diseased eyes was the aerobic pathogen most often isolated. Anaerobic bacteria were isolated from 172 (63.0%) of the conjunctivas. Propionibacterium acnes was isolated from 126 (46.2%) of the conjunctivas, and Peptostreptococcus species were isolated from 80 (29.3%) of the conjunctivas. Comparison with the bacteriology of 96 normal eyes showed that anaerobes play a much greater role as etiological agents of conjunctivitis than formerly believed. When anaerobic bacteria were isolated, they appeared on the average in 7 days, indicating that they may be missed by ordinary bacteriological culturing. 相似文献