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181.
SS Marennikova PV Gashnikov OA Zhukova EI Riabchikova VV Strel''tsov OI Riazankina EV Chekunova NN Ianova SN Shchelkunov 《Canadian Metallurgical Quarterly》1996,(4):6-10
The study included 138 patients operated on for endo-extracellular pituitary adenomas which extend both intracranially and into the structures of the base of the skull. Operations via transcranial and transsphenoidal access to various tumor sites were performed in 38 patients (a main group), while 100 patients (a control group) underwent one of these operations. Two-stage operations, followed by removal of the suprasellar and basal regions of a tumor, are expedient for enhancing the efficiency of surgical treatment, reducing the incidence of complications associated with traumatic attempts at removing tumor parts hard-to-reach by transcranial or transsphenoidal approaches, as well as at reducing the number of relapses. At the first stage of surgical treatment it is advisable to make an intervention via transcranial access especially in cases of complex configuration of the suprasellar part of a tumor. The recommended interval between transcranial and transsphenoidal surgeries is 3-5 months. Two-stage surgical treatment does not lead to significant structural changes and to the increased number of complications, and to higher mortality rates as compared to one-stage surgery (transcranial or transsphenoidal surgeries alone). 相似文献
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SN Radiuk GR Matsevich VZ Tarantul OG Andzhaparidze 《Canadian Metallurgical Quarterly》1994,39(2):53-56
The incidence of chronic alcoholism among the non-medical staff of a hospital was evaluated in an occupational health service context. Three criteria were sought routinely: suspicion by history of excessive alcohol intake, typical findings by physical examination, and suggestive behavioural changes reported by work colleagues. Gamma glutamyl transpeptidase levels and mean corpuscular volume were measured when one of these three criteria existed. The diagnosis of chronic alcoholism was made when two criteria were found or when only one criterion existed but accompanied by laboratory abnormalities. The incidence of chronic alcoholism was 6.2 per cent among male staff and 0.6 among female staff. It appeared to be less than in the population as a whole. The selective and non-systematic use of laboratory investigations and the frequent absence of indication to the occupational health physician of behavioural problems were sources of bias which probably contributed to underestimation of the incidence of chronic alcoholism among employees of the Orleans Regional Hospital Group. Provision of information to all staff is essential in order to explain the behavioural changes associated with chronic alcoholism and the usefulness of reporting employees showing evidence of such changes to the occupational physician. This enables medico-social diagnosis and the early care of those with early chronic alcohol abuse. 相似文献
185.
In an attempt to circumvent the need for 24-hour urine collections for estriol analyses in assessment of fetal status, the possibility of using morning urine samples was investigated. Results indicate 1) good correlation between 24-hour estriol excretion and morning estriol concentration, and between corresponding E/C ratios, 2) similar morning and 24-hour estriol concentrations, 3) high dependence of estriol and creatinine excretion on 24-hour urine volume but not on morning volume, 4) larger variations in 24-hour than in morning urine volume, and 5) better consistency of values in morning than in 24-hour samples in pathologic pregnancy. The use of serial morning urine concentrations at least as an outpatient monitoring procedure is suggested. 相似文献
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JR Reinfelder NS Fisher SN Luoma JW Nichols WX Wang 《Canadian Metallurgical Quarterly》1998,219(2-3):117-135
The bioaccumulation of trace elements in aquatic organisms can be described with a kinetic model that includes linear expressions for uptake and elimination from dissolved and dietary sources. Within this model, trace element trophic transfer is described by four parameters: the weight-specific ingestion rate (IR); the assimilation efficiency (AE); the physiological loss rate constant (ke); and the weight-specific growth rate (g). These four parameters define the trace element trophic transfer potential (TTP = IR.AE/[ke + g]) which is equal to the ratio of the steady-state trace element concentration in a consumer due to trophic accumulation to that in its prey. Recent work devoted to the quantification of AE and ke for a variety of trace elements in aquatic invertebrates has provided the data needed for comparative studies of trace element trophic transfer among different species and trophic levels and, in at least one group of aquatic consumers (marine bivalves), sensitivity analyses and field tests of kinetic bioaccumulation models. Analysis of the trophic transfer potentials of trace elements for which data are available in zooplankton, bivalves, and fish, suggests that slight variations in assimilation efficiency or elimination rate constant may determine whether or not some trace elements (Cd, Se, and Zn) are biomagnified. A linear, single-compartment model may not be appropriate for fish which, unlike many aquatic invertebrates, have a large mass of tissue in which the concentrations of most trace elements are subject to feedback regulation. 相似文献
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