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61.
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PL Bradshaw 《Canadian Metallurgical Quarterly》1995,21(5):975-979
The British National Health Service has recently undergone the most profound reforms since it was conceived some 50 years ago. In an attempt to contain the rising cost of spending the principles of market competition have been introduced. Similar developments are occurring internationally. This paper describes briefly the history of the reforms in the United Kingdom. It outlines the rationale for a market in health services which is largely publicly funded. The paper then provides an analysis of the serious impact of the new business culture on the control of nurses and nursing work in hospitals. In doing so, it identifies the threats which confront the future well-being of the nursing profession. It concludes with a brief resumé of opportunities which the profession must seize if it is to retain its identity. 相似文献
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The regulation by neuropeptide Y of alpha2-adrenoceptors in the nucleus tractus solitarii was evaluated in the adult normotensive Wistar Kyoto rat and the adult spontaneously hypertensive rat. The microinjection of a submaximal dose of l-noradrenaline (800 pmol in 50 nl) alone into the nucleus tractus solitarii produced a significant reduction in the mean arterial blood pressure in either strain. The threshold dose (1 pmol in 50 nl) of neuropeptide Y(1-36) for the vasodepressor response in the Wistar Kyoto rat was five times higher than that (0.2 pmol in 50 nl) in the spontaneously hypertensive rat. Furthermore, neuropeptide Y(1-36) at 0.2 pmol in 50 nl could significantly counteract the vasodepressor response to l-noradrenaline (800 pmol in 50 nl) in the spontaneously hypertensive rat, but not in the Wistar Kyoto rat, in which 1 pmol in 50 nl of neuropeptide Y(1-36) must be employed to counteract the vasodepressor response to l-noradrenaline (800 pmol in 50 nl), although the vasodepressor responses are of a similar magnitude. The in situ hybridization and quantitative receptor autoradiographical experiments showed that the alpha2A-adrenoceptor messenger RNA levels and the B(max) value of the alpha2-adrenoceptor agonist [3H]p-aminoclonidine binding sites measured in the nucleus tractus solitarii of the spontaneously hypertensive rat were substantially lower than those in the Wistar Kyoto rat. The quantitative receptor autoradiographical results were consistent with the cardiovascular results and showed that in the spontaneously hypertensive rat, neuropeptide Y(1-36) at 1 nM led to a significant increase in the K(d) value of [3H]p-aminoclonidine binding sites. In the Wistar Kyoto rat, neuropeptide Y(1-36) produced this effect only at 10 nM. The present study provides evidence for an increase of the potency of neuropeptide Y(1-36) to antagonistically modulate alpha2-adrenoceptors in the nucleus tractus solitarii of the spontaneously hypertensive rat. This enhanced antagonistic action may partly be related to a reduction in the number of alpha2A-adrenoceptors in the nucleus tractus solitarii of the spontaneously hypertensive rat, since a decrease has been observed in the alpha2A-adrenoceptor messenger RNA levels and the alpha2-adrenoceptor binding sites in the spontaneously hypertensive rat. This increased potency of neuropeptide Y(1-36) to antagonize alpha2-adrenoceptor function in the nucleus tractus solitarii of the spontaneously hypertensive rat may contribute to the development of high blood pressure in this hypertensive strain. 相似文献
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M Koutroumanidis CD Binnie CP Panayiotopoulos 《Canadian Metallurgical Quarterly》1998,19(12):1123-1126
Epilepsy research using positron emission tomography (PET) has advanced our understanding of the pathophysiology and neurochemical correlates of both focal and generalized epilepsies, but from the clinical viewpoint its major contribution has been in the presurgical evaluation of patients with medically intractable partial seizures. Depending on the tracer used, PET may provide information on regional cerebral blood flow and glucose metabolism, and the binding of specific ligands to receptors that are thought to be related to the genesis and propagation of epileptic activity. In this communication, we discuss the diagnostic yield, limitations and perspectives of 18F-fluorodeoxyglucose (FDG) and 11C-flumazenil (FMZ) PET in partial epilepsies. The current evidence regarding the pathophysiology of the focal changes is also presented, with an emphasis on issues which must be carefully addressed for effective and reliable clinical research. 相似文献
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JM Matthews-Greer JM Eggerstedt E Gonzalez RM Jamison CD Washington 《Canadian Metallurgical Quarterly》1998,178(6):1860-1861
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Most breast mass lesions are readily characterized by FNA with cytodiagnosis. Occasionally, benign but markedly proliferative lesions are diagnostically difficult to separate from well differentiated malignancies. We present information pertaining to the diagnostic significance of two cytologic findings observed in breast aspiration specimens, namely pairs of stripped bipolar nuclei and signet ring cells (SRC). We have evaluated aspirate smears from 219 cases of histologically proven benign (n = 114) and malignant (n = 105) breast lesions. Both singlets and pairs of bipolar nuclei and SRC were enumerated, and their numbers were correlated to histological diagnosis. Closely associated pairs of stripped bipolar nuclei were found in 68% of benign lesions compared with only 3.8% of carcinomas, establishing their presence as a highly specific indicator of a benign process. Large numbers of such 'benign pairs' also favoured the diagnosis of fibroadenoma. SRC were identified in 66% of histologically proven carcinomas (67% of ductal and 70% of lobular). SRC were also present in 10% of histologically benign cases. In the malignant cases, SRC were most frequently noted in a single cell distribution or within small, loosely cohesive tissue fragments. In the benign instances, SRC were most commonly noted within large fragments, and many of these cells were proved by immunohistochemical reactions to be vacuolated myoepithelial cells. We conclude that the presence of bipolar nuclei in closely associated pairs suggests benignity and aids in the subclassification of benign breast masses. In addition, the presence of SRC does not aid in the classification of tumour subtype (ductal vs lobular), and the occurrence of such cells in the proper context should prompt surgical biopsy. 相似文献