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991.
992.
V M Heimbach D E Henninger 《Insight (American Society of Ophthalmic Registered Nurses)》1991,16(2):24-25
In summary, ambulatory surgery requires patients and their families to assume responsibilities previously held by health care providers. These include preserving NPO instructions without the benefit of nurses present to prevent a break in the fast. Nurses responsibilities then, take on a different meaning. An essential nursing objective is to enlighten patients. 相似文献
993.
David Heseltine Michael Dakkak Ian A. Macdonald PhD Stephen R. Bloom MD John F. Potter DM 《Clinical autonomic research》1991,1(3):219-224
Previous studies have demonstrated that blood pressure falls postprandially in fit elderly subjects, the greatest changes occurring after meals with a high carbohydrate content. To evaluate the influence of the type of carbohydrate on postprandial blood pressure, the effects of equivalent energy content (2.4 MJ) high complex (starch) and high simple (monosaccharide) carbohydrate meals were studied in seven healthy elderly subjects. Blood pressure, heart rate, autonomic function, plasma catecholamines, insulin and neurotensin levels were measured pre- and postprandially. Greater falls in supine and erect systolic blood pressure occurred after the high simple than the high complex carbohydrate meal (p < 0.05). No differences were found in supine or erect diastolic blood pressure, heart rate or in any of the biochemical parameters measured between the meal types. It is concluded that a simple carbohydrate meal results in a greater postprandial fall in blood pressure than an equivalent energy complex carbohydrate meal in the elderly, although the mechanisms for these changes are unknown. 相似文献
994.
995.
Value of non-invasive continuous blood pressure monitoring in the detection of carotid sinus hypersensitivity 总被引:1,自引:0,他引:1
Christopher J. Mathias DPhil Elaine Armstrong BSc Norman Browse K. R. Chaudhuri Peter Enevoldson DPhil Ralph W. Ross Russell DM 《Clinical autonomic research》1991,1(2):157-159
A patient with recurrent episodes of dizziness and blackouts is described. Detailed cardiac and neurological investigations were normal. Autonomic assessment excluded postural hypotension and confirmed normal sympathetic vasoconstrictor function. Cardiac parasympathetic function in response to deep breathing, hyperventilation and ocular pressure was normal. Left carotid sinus massage only reproducibly lowered blood pressure with minimal change in heart rate. This occurred mainly during head-up tilt. The fall in blood pressure was not affected by the muscarinic blocker atropine, or the peptide release inhibitor, octreotide. A diagnosis of left carotid sinus hypersensitivity of the vasodepressor variety was made. Left carotid sinus denervation was performed. This successfully prevented further episodes of dizziness and blackouts. The ability to measure beat-to-beat blood pressure non-invasively was of particular importance in diagnosis, and in the assessment of management options in this patient. 相似文献
996.
997.
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1000.
Correlative morphologic and molecular genetic analysis demonstrates three distinct categories of posttransplantation lymphoproliferative disorders 总被引:36,自引:11,他引:25
Knowles DM; Cesarman E; Chadburn A; Frizzera G; Chen J; Rose EA; Michler RE 《Blood》1995,85(2):552-565
The posttransplantation lymphoproliferative disorders (PT-LPDs) are a morphologically heterogeneous group of Epstein-Barr virus (EBV)-driven lymphoid proliferations of varying clonal composition. Some PT-LPDs regress after a reduction in immunosuppression, while others progress in spite of aggressive therapy. Previously defined morphologic categories do not correlate with clonality, and neither morphology nor clonality has reliably predicted the clinical behavior of PT-LPDs. We investigated 28 PT-LPD lesions occurring in 22 patients for activating alterations involving the bcl-1, bcl-2, c-myc, and H-, K- and N-ras proto-oncogenes and for mutations involving the p53 tumor suppressor gene. We correlated the results of these studies with the morphology of the lesions, their clonality based on Ig heavy and light chain gene rearrangement analysis, and the presence and clonality of EBV infection. We found that the PT-LPDs are divisible into three distinct categories as follows: (1) plasmacytic hyperplasia: most commonly arise in the oropharynx or lymph nodes, are nearly always polyclonal, usually contain multiple EBV infection events or only a minor cell population infected by a single form of EBV, and lack oncogene and tumor suppressor gene alterations; (2) polymorphic B-cell hyperplasia and polymorphic B-cell lymphoma: may arise in lymph nodes or various extranodal sites, are nearly always monoclonal, usually contain a single form of EBV, and lack oncogene and tumor suppressor gene alterations; and (3) immunoblastic lymphoma or multiple myeloma: present with widely disseminated disease, are monoclonal, contain a single form of EBV, and contain alterations of one or more oncogene or tumor suppressor genes (N-ras gene codon 61 point mutation, p53 gene mutation, or c-myc gene rearrangement). The PT-LPDs are divisible into three categories exhibiting distinct morphologic and molecular genetic characteristics. Alterations involving the N-ras and c-myc proto- oncogenes and the p53 tumor suppressor gene may play an important role in the development and/or progression of the PT-LPDs. 相似文献