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排序方式: 共有549条查询结果,搜索用时 15 毫秒
51.
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53.
Magnetic resonance appearance of peripheral nerve sheath tumors 总被引:6,自引:0,他引:6
Margaret A. Stull M.D. Richard P. Moser Jr. Mark J. Kransdorf George P. Bogumill M.D. Martha C. Nelson M.D. 《Skeletal radiology》1991,20(1):9-14
Magnetic resonance imaging (MRI) was used to evaluate 22 histologically proven peripheral nerve sheath tumors, approximately two-thirds of which arose in the lower extremity. The histologic distribution was as follows: 12 schwannomas, 7 neurofibromas, and 3 malignant peripheral nerve sheath tumors (2 of which occurred in patients with neurofibromatosis). Most lesions demonstrated an intermediate to moderately bright signal on T1-weighted images and were minimally inhomogeneous. All lesions were moderately bright on proton-density-weighted images and bright on T2-weighted images, again with variable inhomogeneity. The extent of the tumor was best assessed on proton-density- and T2-weighted images. Smooth margins were noted in 19 lesions. Of the 3 remaining lesions, 2 were malignant (but had been subjected to biopsy prior to MRI), and the other lesion was a plexiform neurofibroma. MRI accurately determined the relationship between the lesion and the adjacent neurovascular structures and muscles, thereby assisting surgical management. On MRI, 5 lesions demonstrated coexistent subtle muscle atrophy along the longitudinal axis of surrounding or distally innervated musculature. This latter finding, together with the presence of a tumor in the vicinity of a large nerve trunk, suggests a peripheral nerve sheath neoplasm.The opinions and assertions contained herein are the private views of the authors and do not reflect the views of the Uniformed Services University of the Health Sciences, the Department of the Army, or of the Department of Defense 相似文献
54.
G. Eisenhofer D. S. Goldstein R. W. Stull P. W. Gold H. R. Keiser I. J. Kopin 《Clinical and experimental pharmacology & physiology》1987,14(4):337-341
1. The pituitary-adrenocortical, sympathoadrenomedullary and renin-angiotensin-aldosterone systems contribute to circulatory and metabolic homeostasis during stress. One possible site of co-ordination of these systems is the beta-adrenoceptor. 2. To determine whether circulating beta-adrenoceptor agonists can act hormonally to stimulate these systems simultaneously, plasma concentrations of corticotrophin (ACTH), noradrenaline, adrenaline and plasma renin activity were measured during graded intravenous infusions of isoprenaline in 20 people. 3. Administration of isoprenaline caused dose-related increases in noradrenaline (94% at the highest dose) and renin activity (189%), but decreases in ACTH (25%) and adrenaline (20%), findings inconsistent with simultaneous activation of these systems by circulating beta-adrenoceptor agonists. 相似文献
55.
Severe malaria in children in Papua New Guinea 总被引:1,自引:0,他引:1
Allen SJ; O'Donnell A; Alexander ND; Clegg JB 《QJM : monthly journal of the Association of Physicians》1996,89(10):779-788
The clinical features of severe falciparum malaria and risk factors for
mortality were studied in 489 children admitted with malaria to Madang
Hospital, Papua New Guinea. The most common severe manifestations of
malaria were severe anaemia (22%) and coma (16%). Children with severe
anaemia were younger than those with coma (median age 2.2 vs. 3.7 years)
and had been ill for longer before admission (median 7 vs. 4 days,
respectively). Although the clinical features of coma in Madang children
with malaria resembled closely those reported in African children,
mortality was lower (8% vs. 17-25%, respectively). Overall, 17 (3.5%)
children died, most within 12 h of admission. A high level of plasma
lactate (> or = 5 mmol/l) was common (20%) and was the major predictor
of death in multiple regression analysis. Raised plasma creatinine and
decreased plasma bicarbonate were also independent predictors of mortality.
Coma was not predictive of death, although a high proportion of children
with profound coma died. Investigation of the causes of acidosis in
children with malaria is a high research priority. In view of the short
time interval between admission and death in many children, emphasis must
be placed on the prevention or early recognition and treatment of acidosis
in the district health clinic as well as the central hospital.
相似文献
56.
Little is known about dopamine pharmacokinetics in pediatric patients, especially in critically ill infants and children who often receive treatment with dopamine. Arterial plasma concentrations of dopamine were measured in 27 patients who were hemodynamically stable and received dopamine for at least one hour. The dopamine levels were measured using liquid chromatography with electrochemical detection. Dopamine clearance averaged 96.2 +/- 55.4 ml/kg.min in 13 patients in the neonatal ICU, and 58.8 +/- 51 ml/kg.min in 14 patients in the pediatric ICU. Six patients had renal (BUN greater than 25 mg/dl, or creatinine greater than 1.2 mg/dl) or hepatic (liver enzymes greater than 3 times normal) dysfunction. Dopamine clearance in these patients (25.1 +/- 17.2 ml/kg.min) was substantially lower than in the other patients (p less than .01). Neither postnatal nor gestational age correlated with dopamine clearance. Substantial interindividual variation was observed in steady-state dopamine clearance in critically ill infants and children, and plasma dopamine could not be predicted accurately from the dopamine infusion rate. Because of the more than three-fold prolongation of dopamine clearances in patients with hepatic or renal dysfunction, these patients may be more likely to suffer toxic effects of dopamine at the usual drug infusion rates. 相似文献
57.
58.
Patterns of Depressive Symptoms in Children 总被引:1,自引:0,他引:1
Mary K. Bailey ND APN RN Jaclene A. Zauszniewski PhD RN-BC FAAN Marjorie M. Heinzer PhD APRN BC CRNP Marion Hemstrom-Krainess DNSc RN CS 《Journal of child and adolescent psychiatric nursing》2007,20(2):86-95
PROBLEM: Depressive symptoms in children have been linked to recurrent problems with depression, school problems, and risky health behaviors. Adolescent girls report depressive symptoms three to four times more frequently than adolescent boys. Few studies, however, have examined gender-related depressive symptoms in younger, school-aged children. METHODS: In the present study, gender differences in depressive symptoms in children ages 10-12 years were explored using the Children's Depression Inventory (CDI) with a convenience sample of 122 suburban middle-class public school fifth and sixth graders. FINDINGS: A distinct pattern of depressive symptom expression was found with girls reporting more internalizing and more negative self-esteem, and boys reporting more externalizing and more school problems. CONCLUSION: These findings suggest that despite similarities on a total depressive symptom score, there are distinct gender differences in depressive symptom expression that are identifiable before adolescence and may be associated with normative development. 相似文献
59.
60.
A Pareek SD Zawar SB Salagre NB Chandurkar ND Karnik 《European journal of medical research》2009,14(7):297-303