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991.
Carcinoma of the gallbladder   总被引:1,自引:0,他引:1  
Gallbladder carcinoma is the fourth commonest gastrointestinal malignancy. Its growth is insidious and the majority of cases are advanced at the time of diagnosis. The recognized radiological features occur only in those with advanced disease. Cholecystectomy may be curative when carcinoma is confined to the gallbladder but the place of extensive surgery, chemotherapy or radiotherapy is unproven.  相似文献   
992.
993.
The immunohistochemical localization of manganese (Mn)-superoxide dismutase (Mn-SOD) was studied in the rat basal forebrain using polyclonal antibodies to Mn-SOD. Neurons of the basal forebrain exhibit a high density of Mn-SOD immunoreactivity. Double immunostaining with a monoclonal antibody to choline acetyltransferase demonstrated that both cholinergic and non-cholinergic neurons in the basal forebrain are intensely immunoreactive for Mn-SOD.  相似文献   
994.
We studied angiographic findings of 56 patients who were diagnosed as lacunar infarcts in the basal ganglia or deep subcortical white matter based on clinical symptomatology and brain computed tomography. In 26 patients with CT lesions less than 15 mm in diameter, only eight (31%) showed minor angiographic findings. In 30 patients with lesion of 15 mm or more, however, 22 (73%) had abnormal angiographic findings. Fourteen of the 22 patients had minor irregularities, three had 25-75% stenosis, five had 75% less than stenosis at the bifurcation of the common carotid artery or the horizontal portion of the middle cerebral artery. Our findings support the notion that a small lesion on CT can result from an occlusion of the perforating artery itself and a larger lesion is much related to the major vessel or heart diseases, i.e., emboli from the parent artery or heart, obstruction of perforators at their origin by an atheromatous plaque of the horizontal portion of the middle cerebral artery, or terminal zone infarct due to hemodynamically significant stenotic lesion. In patients with a larger deep infarct on CT, further investigation of the arteries in the carotid-axis and heart is important for determination of therapeutic indication.  相似文献   
995.
Whole-cell voltage clamp recordings in 400 microns thick hippocampal slices revealed discrete excitatory and inhibitory postsynaptic currents which persisted at synapses on granule cells following abolition of action potentials with 1 microM tetrodotoxin (TTX). The conductances associated with excitatory amino acid and GABAA receptor mediated events had mean peaks of 200 and 800 pS, and decayed monoexponentially with time constants of 5.6 and 5.3 ms. At a holding potential close to the normal resting membrane potential of granule cells (-80 to -90 mV), the frequency of glutamate/aspartate mediated spontaneous excitatory postsynaptic currents (sEPSCs) was decreased from 2.04 Hz in slices cut parallel to the plane of the perforant path to 0.87 Hz in slices cut in a plane that disrupted the distal perforant path fibres, suggesting that presynaptic integrity influences the rate of action potential independent neurotransmitter release. The orientation of the slicing had no effect on the frequency of spontaneous inhibitory postsynaptic currents (sIPSCs).  相似文献   
996.
The study of urinary sediment is essential in laboratory diagnosis. Conventional clinical methods are now used in line with computer-aided techniques and additional microscopy of the sediment elements. The paper provides a brief analysis of clinical situations characterized by appearance in the urine of abnormal numbers of leukocytes, erythrocytes, casts; provides clinical assessment of additional microscopic methods able to accentuate qualitative characteristics of the urinary syndrome; considers possibilities of application of the urinary sediment data in follow-up to improve diagnosis and control on-going treatment.  相似文献   
997.
This case study illustrates the chronic nature of hyperlipidemia type IIa and the important contribution of the nurse in helping the client adjust life style, manage complex health regimes, and cope with the uncertainty of disease progression and its associated risks.  相似文献   
998.
In the first part of this series on issues in ward management facing charge nurses, Helen Evers addresses the problem of communication between hospital and community on patient discharges. Recent years have seen the development of liaison and co-ordinator posts whose incumbents aim to facilitate planned and organised discharge procedures, but the appointment of such personnel may not provide a complete answer to the problem. The ultimate arbiter of effective transition from hospital to home is more likely to be the quality of communication between charge and district nurse.  相似文献   
999.
1000.
Human alpha-fetoprotein (AFP) was isolated from human abortive tissue by biospecific chromatography on immobilized estrogens. The most effective sorbents were: estrone-0-3-hemisuccinyl-hexamethylenediamine-Sepharose CL 4B and diethylstilbestrol-diasoanisole-sulfonyl-oxyethyl-Sepharose CL 4B. As elution solution the most optimum was 10% buffered aqueous butanol. Taking into consideration the data obtained, one can conclude that AFP in human biological fluids is bound to immobilized estrogens. Butanol extraction deestrogenizes AFP, and as a result human AFP acquires affinity to immobilized estrogens. During rechromatography on immobilized diethylstilbestrol, it was possible to obtain AFP preparations of about 95% purity. The present results provide the opportunity to work out new methodological approaches to human AFP isolation using biospecific chromatography on immobilized estrogens.  相似文献   
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