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Fernando Arroyave L.M.S. Dip. Psych. Doreen Little M.A. Felix Letemendia M.D. D.P.M. Richard de Alarcon M.D. D.P.M. 《Addiction (Abingdon, England)》1973,68(2):129-135
Home Office statistics provide some evidence of the rapid growth of heroin abuse. In 1960 there were 63 known addicts in the age group 34 years and under, and by 1968, when notification of addiction to heroin was made compulsory under the Notification of Addicts' Act, the number had risen to 2,294. The use of methadone (“Physeptone”) both in withdrawal and in long-term maintenance therapy, has resulted in cases of additional dependence. The aim of this paper is to present an enumerative survey of abuse of these two drugs by persons of 30 years of age and under, known to have resided at some time within the Oxford City boundaries during the year 1969. The initial model for this study was that published by de Alarcon and Rathod in 1968.1 相似文献
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The purposes of this two-year research study were to uncover Chilean nurses' perspectives of the elements that comprise leadership, and to identify challenges faced by nurse leaders in modern health administration. The research question is, What are the structural components that define and characterize nursing leadership in Chile? Nine nurses from different professional backgrounds volunteered to take part in audiorecorded successive interviews. The research methodology was a kind of grounded theory. Findings suggest that leadership is characterized mainly by exerting a positive influence on others based on good communication, knowledge of management, and a futurist vision of the nursing profession. Crisis and transition in nursing leadership were associated with external and internal forces, such as reforms in healthcare organizations and changes in the nursing conceptual framework. 相似文献
66.
Ferrer E Cabrera Z Rojas G Lares M Vera A de Noya BA Fernandez I Romero HU Harrison LJ Parkhouse RM Cortez MM 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2003,97(5):522-526
A serological study was undertaken in 1998 to evaluate levels of Taenia solium cysticercosis in 3 rural Venezuelan communities. Infection with viable metacestodes was diagnosed with a trapping enzyme-linked immunosorbent assay (ELISA) that detects a secreted product of viable parasites. Anti-metacestode antibodies were assayed by ELISA using T. solium vesicular fluid as antigen. A total of 1254 sera was collected from 3 communities (Canoabo, Sanare, and Rio Tocuyo) where previous studies had suggested the presence of T. solium. Our results demonstrate an unusually high seroprevalence of cysticercosis, indicating an attendant risk of transmitting the disease to other areas. The seroprevalence of infection with viable cysts, as indicated by detection of circulating parasite antigen, was 9.1% in Canoabo, 6.1% in Sanare, and 5.7% in Rio Tocuyo. The corresponding frequency of antibodies to T. solium cyst antigens was 36.5% in Canoabo, 36.5% in Sanare, and 4% in Rio Tocuyo. As these communities are probably representative of many others in Venezuela, T. solium cysticercosis may be a significant public health problem and more work is certainly indicated. An important finding was that local knowledge of the disease and its transmission do not necessarily guarantee diminished disease prevalence, indicating a lack of appropriate vigilance towards disease control. 相似文献
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A total of 140 sets of abdominal radiographs were reviewed independently by four qualified diagnostic radiologists. The degree of interobserver agreement was determined by calculating kappa values for 19 commonly used radiographic signs and diagnoses. There was fair to excellent interobserver agreement for 11 signs and diagnoses and poor agreement for the remaining eight. The signs and diagnoses for which agreement is poor cannot be considered reliable and include particularly large bowel obstruction and nonspecific gas pattern. 相似文献
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The effects of section separation on image contrast and calculated T1 relaxation times were investigated in healthy volunteers and a phantom using an early commercial version magnetic resonance imaging system. The effects are explained qualitatively on the basis of side lobes of excitation occurring outside the selected section resulting in reduction of the time permitted for T1 relaxation. The options for dealing with imperfect section selection, including separation of the sections (i.e., leaving gaps) and nonsequential excitation, are illustrated and the trade-offs involved in each explained. 相似文献
69.
Several processes relating to the cholinergic system that are present in human blood were measured in samples obtained from patients with bipolar affective disorder, both before and during treatment with lithium, and from controls. The biochemical measurements include RBC and plasma choline concentrations, the kinetics of RBC choline uptake, plasma non-specific cholinesterase and RBC and plasma acetylcholinesterase. The RBC choline level is increased and the Vmax of the RBC choline uptake system is decreased in samples from lithium-free bipolar patients during manic episodes. There are no differences from control in the plasma choline levels or in the acetylcholinesterase enzyme activities in blood samples from the lithium-free or lithium-treated patients. Plasma non-specific cholinesterase is below control levels in all patients. Lithium treatment increases the RBC choline concentration to more than ten-times control levels and reduces the Vmax and the affinity for choline of the RBC choline transport system. In vitro addition of lithium does not replicate the effects of in vivo administration of lithium. Possible mechanisms for these effects of lithium are discussed. 相似文献
70.
Single unit electrical activity has been recorded from viscerosomatic neurons in the lower thoracic spinal cord of decerebrate spinalized cats. The responses of the cells to electrical stimulation of afferent fibres in the splanchnic (SPLN) nerve and the effects of repetitive stimulation of somatic and visceral afferent C-fibres have been studied. Four groups of viscerosomatic neurones could be distinguished according to the type of visceral afferent input of the cells: (1) A-only cells (32.9%), driven only by stimulation of A delta afferent fibres in the SPLN nerve; (2) C-only cells (3%), driven only by stimulation of C afferent fibres in the SPLN nerve; (3) A + C cells (45.7%), driven by both A delta and C afferent fibres in the SPLN nerve; and (4) A + C? cells (18.6%), driven by A delta visceral afferents and showing signs of responsiveness to C-fibres though lacking a distinct response volley to visceral C-fibre activation. Two cells of the A + C group and located in lamina I of the dorsal horn responded to SPLN nerve stimulation in a manner consistent with the afferent fibre composition of the nerve, that is, showed evidence of strong monosynaptic links with SPLN afferent C-fibres and weaker responses to SPLN A delta afferents. Excitability changes of viscerosomatic neurones ('wind up', 'wind down' and changes in background activity) were also observed in the majority of neurones following electrical stimulation of somatic and of visceral afferent C-fibres.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献