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81.
Dr James H. Philip ME MD Daniel B. Raemer PhD 《Journal of clinical monitoring and computing》1986,2(3):151-154
A prototype electronic monitoring stethoscope was constructed from readily available, high-quality components. It consisted of a conventional precordial or esophageal probe connected to a microphone by a rubber adapter. The microphone was connected by lightweight wire to an amplifier and headphones. Twenty-one anesthesia clinicians evaluated the stethoscope and responded to a multiple-choice preference questionnaire. The electronic stethoscope was judged to perform better than the conventional stethoscope in most categories evaluated. The electronic device was perceived to be louder, clearer in sound reproduction, more efficacious for monitoring, and easier to use continuously, and its head-phones were considered more comfortable than the conventional carpiece. Based on our results, we conclude that amplified stethoscopes have the potential to improve monitoring. Further development of electronic stethoscope monitoring seems warranted and is continuing. 相似文献
82.
WILLIAMS PS; STEVENS ME; FASS G; IRONS L; BONE JM 《QJM : monthly journal of the Association of Physicians》1991,81(1):837-855
SUMMARY Ninety-five patients (63 male, 32 female), age 45±2 years(mean±SEM) with chronic renal failure of varied aetiologywere randomized to receive either a conventional low proteindiet (0.6 g/kg/day protein, 800 mg phosphate; n=33), a low phosphatediet (providing approximately 1000 mg phosphate plus an orallyadministered phosphate binder, minimum protein intake 0.8 g/kg/day;n=30) or to control (minimum protein intake 0.8 g/kg/day, nophosphate restriction; n=32). Patients were reviewed for a minimumof 6 months before randomization and were withdrawn from thestudy if plasma creatinine exceeded 900 µmol/1, plasmaphosphate was > 2.0 mmol/1 or at the onset of uraemic symptoms. Following randomization patients were studied for an averageof 19±3 months. Mean plasma creatinine rose from 398±33to 600±50 µmol/1. Dietary protein intake was estimatedat 0.69±0.02 g/kg/day in the low protein group, 1.02±0.05in the low phosphate and 1.14±0.05 in the controls, phosphateintake was 815±43, 1000± 47, and 1315±57mg/day, respectively. Urinary urea excretion and protein catabolicrates were significantly reduced (p<0.01) only in those onprotein restriction, at 213±9 mmol/24 hours and 0.71g/kg/day, respectively. Phosphate excretion was significantlylower (p<0.05) in both the low protein group (17.9±0.8mmol/24 hours) and the low phosphate group (18.6±1.0mmol/24 hours) compared to controls. Changes in body weight,muscle mass and serum transferrin, albumin and immunoglobulinswere comparable between the groups. Mean blood pressure followingrandomization was 150/89±3/1 (low protein), 148/87±3/1(low phosphate) and 146/87±3/1 (controls). Progression of renal failure was analysed by rate of fall ofcreatinine clearance (ml/min/ 1.73 m2/month), by rate of deteriorationderived from reciprocal plasma creatinine against time plots(1/mmol/year) and to assess individual patient's response totreatment by two phase linear regression (breakpoint)analysis of reciprocal plasma creatinine/time plots. Progressionwas analysed only in patients seen for at least 3 months followingrandomization. The rate of fall of creatinine clearance was not significantlydifferent between the groups (ANOVA): 0.56±0.08 ml/min/1.73m2/month (low protein, n=28), 0.44±0.07 (low phosphate,n=23) and 0.69±0.11 (control, n=27). In 50 patients (18low protein, 16 low phosphate and 16 control) whose rate ofprogression could be calculated before and after randomization,there was a fall in rate of progression averaging 0.18 ml/min/1.73m2/month in those on low protein diet and those on low phosphatediet, but a rise of 0.08 in the controls. These differenceswere, however, not statistically significant. Similar resultswere obtained when the rates of deterioration were calculatedfrom plasma creatinine. Significant individual improvements(p<0.01) in rates of progression by breakpointanalysis occurred in 17 patients: six on low protein, sevenon low phosphate and in four controls. Sixty-one (72 per cent)of the patients examined by this method showed no significantchange in the rate of progression while seven patients had acceleratedprogression. There was no difference in the requirement formaintenance dialysis facilities between groups. No significant benefit of protein and phosphate restrictionwas therefore demonstrated. 相似文献
83.
ME Lenaerts 《Cephalalgia : an international journal of headache》2008,28(S1):12-15
The ICHD-II criteria for post-traumatic headache (PTH) are strictly outlined. PTH can be subdivided into an acute and a chronic forms, the former likely nociceptive in nature, the latter likely neuropathic. The time of transition between the acute and the chronic forms is artificial and in the future should be better based on clear clinical or rather biological data. Chronic PTH often presents as one of the primary headache syndromes, e.g. migraine or tension-type headache. Its biology is poorly understood and whether it merely represents the expression of the primary headache or it has a distinct pathogenesis remains unclear. The frontal lobe is often affected in traumatic head injury. Its dysfunction can cause an array of clinical consequences that have an impact on the patient's symptomatology and therapeutic outcome. Its recognition is likely to improve patient management quality. 相似文献
84.
Time-dependent loss of surface complement regulatory activity during storage of donor blood 总被引:2,自引:0,他引:2
The survival of transfused red cells (RBCs) diminishes with time of in vitro storage in blood banks, but the molecular mechanisms underlying the slow but incessant deterioration are incompletely understood. To investigate the possibility that impaired resistance to autologous complement attack could play a role in this phenomenon, packed RBCs stored for variable periods were assayed for decay-accelerating factor (DAF) and CD59, two glycoinositol-phospholipid (GPI)-anchored, membrane- associated complement regulatory proteins that function physiologically to protect blood cells from autologous complement activation on their surfaces. Immunoradiometric and flow cytometric assays employing DAF and CD59 monoclonal antibodies showed that levels of both surface proteins gradually declined over 6 weeks. Digestion analyses with phosphatidylinositol-specific phospholipase C, an enzyme that releases GPI-anchored proteins from cell surfaces, showed that DAF and CD59 molecules with GPI anchors containing unacylated inositol were preferentially lost. These findings suggest: 1) that DAF and CD59 molecules with acylated GPI anchors are more stable in RBC membranes than are molecules with unacylated GPI anchors, and 2) that DAF and CD59 loss may participate with other membrane alterations that occur during in vitro storage in compromising the survival of transfused cells. 相似文献
85.
Histamine levels in stored platelet concentrates. Relationship to white cell content 总被引:1,自引:0,他引:1
The histamine levels in samples from platelet concentrates (PC) were measured at various storage times by a radioenzymatic assay. Elevated histamine levels were detected in 5 of 14 PC after 3 days of storage (range, less than 1 to 13.3 ng/ml) and in 9 of 14 PC after 5 days (range, less than 1 to 22.2 ng/ml). A very good linear correlation (r = 0.913) was found between the initial white cell content of the PC and the histamine level at 5 days of storage. The rise in histamine content was not influenced by the type of plastic container. The results indicate a process of histamine release by the white cells during storage. Although histamine is metabolized rapidly in vivo, a critical histamine threshold could be reached in man by the rapid infusion of stored PC containing high levels of histamine. This could explain some unexpected transfusion reactions in patients receiving PC. 相似文献
86.
DF Stroncek ; ME Clay ; ML Petzoldt ; J Smith ; W Jaszcz ; FB Oldham ; J McCullough 《Transfusion》1996,36(7):601-610
BACKGROUND: Granulocyte-colony-stimulating factor (G-CSF) has been used in patients to increase the level of circulating hematopoietic progenitors. Although G-CSF has been administered to some healthy individuals, the kinetics of mobilization of peripheral blood stem cells (PBSCs), the optimum dose schedule and the incidence and nature of adverse reactions in normal individuals are not completely defined. STUDY DESIGN AND METHODS: Normal individuals (n = 102) who received G- CSF for 5 or 10 days at doses of 2, 5, 7.5, or 10 micrograms per kg per day were studied. The subjects were observed for symptoms and physical changes, and blood samples were obtained for a variety of laboratory tests. After 5 or 10 days of G-CSF treatment, PBSCs were collected by apheresis and analyzed. RESULTS: Overall, 89 percent of the individuals completed the 5-day treatment protocol and 88 percent completed the 10- day protocol without modification of the dose of G-CSF administered. Ninety percent of donors experienced some side effect of G-CSF. The most frequent effects noted were bone pain (83%), headache (39%), body aches (23%), fatigue (14%), and nausea and/or vomiting (12%). The dose of G-CSF administered directly affected the proportion of people with bone pain (p = 0.025) or body aches (p = 0.045) or who were feeling hot or having night sweats (p = 0.02) or taking analgesics (p = 0.01). With the 5-day dose schedule, several changes in serum chemistries occurred, including increases in alkaline phosphatase (p = 0.001), alanine aminotransferase (p = 0.0013), lactate dehydrogenase (p = 0.0001), and sodium (p = 0.0001). Decreases occurred in glucose (p = 0.045), potassium (p = 0.0004), bilirubin (p = 0.001), and blood urea nitrogen (p = 0.0017). In donors who received G-CSF for 5 days, the absolute neutrophil count was increased after one G-CSF dose, and it reached a maximum on Day 6, as did the number of CD34+ cells (64.6 +/? 55.9 × 10(6) cells/L). In those same donors, the platelet count after apheresis on Day 6 was 32 +/? 13 percent lower than pretreatment values (250 +/? 42 × 10(9) cells/L). In donors receiving G-CSF for 10 days, the neutrophil count reached a maximum on Day 8, but the number of CD34+ cells peaked on Day 6 (58.3 +/? 52.1 × 10(5) cells/L) and then declined. The platelet count decreased from pretreatment values by 28 +/? 12 percent prior to apheresis on Day 11. When individuals were treated for 5 days with G-CSF, the quantity of CD34+ cells collected was directly related to the G-CSF dose. When 5 micrograms per kg per day was given, 2.80 +/? 1.81 × 10(8) cells were collected, compared with collection of 4.67 +/? 3.11 × 10(8) cells when 10 micrograms per kg per day was given (p = 0.04). More important, PBSCs collected after 10 days of G-CSF administration (5 micrograms/kg/day) had significantly fewer CD34+ cells (0.82 +/? 0.37 × 10(8) cells, p = 0.01) than did PBSCs collected after 5 days of G-CSF (5 micrograms/kg/day). CONCLUSION: Most normal donors receiving G-CSF experience side effects, but these are mild to moderate in degree. Some alterations in blood chemistries occur, but none were clinically serious. Because of the symptoms associated with G-CSF, these individuals must be monitored closely. The treatment of normal donors with G-CSF for more than 5 days significantly decreased the number of circulating CD34+ cells and the quantity collected by apheresis. 相似文献
87.
This article describes a model designed to provide an understanding of fluid flow in intravenous systems and human subjects. Experiments were developed which demonstrate that the model can represent common clinical situations. The model depicts physical devices as ideal resistors, pressure sources, and flow sources. The patient's venous system is depicted as a combination of ordinary and Starling resistors. For flows between 0 and 300 ml/hr, both physical devices and patients are adequately represented by a straight line representing the pressure-flow relationship (PFR): pressure = opening pressure + flow × resistance, where the slope is the resistance to fluid flow and the intercept is the opening pressure. The PFR for a normal vein is characterized by a flat slope (vein resistance =22±20 mm Hg/L/hr, mean ± SD) and a low intercept (opening pressure =15±8 mm Hg). The PFR for a partially obstructed vein has a resistance equal to that of an unobstructed vein and an opening pressure elevated approximately equal to the pressure obstructing the vein. For perivascular tissue, the PFR has a steep slope (tissue resistance =1,125±1,376 mm Hg/L/hr), while tissue opening pressure depends on the amount of fluid infused. At the onset of fluid extravasation (infiltration), tissue pressure usually is lower than venous pressure (8±8 versus 15±8 mm Hg), until fluid fills the distensible tissue compartment. In clinical practice, when infiltration or obstruction occurs, flow decreases and the clinician adjusts the roller clamp until correct flow resumes; no problem is obvious. The combined model for the intravenous tubing and venous systems explains the behavior of current clinical infusion devices.Presented in part at the Sixth Medical Monitoring Technology Conference, Vail, CO, March 1986; at the Annual Meeting of the American Society of Anesthesiologists, Las Vegas, NV, October 1986; at the Seventh Medical Monitoring Technology Conference, Vail, CO, March 1987; at a meeting on Computers in Critical Care and Pulmonary Medicine, San Diego, CA, June 1987; at the Annual Meeting of the American Society of Anesthesiologists, Atlanta, GA, October 1987; at the Regional Meeting of the Association for the Advancement of Medical Instrumentation, Cincinnati, OH, October 1987; at the Institute of Electrical and Electronics Engineers Ninth Annual Conference of the Engineering in Medicine and Biology Society, Boston, MA, November 1987; and at a meeting of the American Society of Hospital Pharmacists, Atlanta, GA, December 1987.Supported in part by grants from IVAC Corp.The author thanks the following individuals for important intellectual and/or technical assistance: Peter Basser, PhD, Avital Cnaan, PhD, Adriane Concus, MD, John Fox, MD, David Gissen, MD, David Joseph, MD, Anne Kamara, David Leith, MD, Leonard Lind, MD, Richard Morris, MB, BS, Barbara Orlowitz, MEE, Mary Anne Palleiko, RN, Beverly Philip, MD, Daniel Raemer, PhD, David Scott, MB, BS, John Stelling, MPH, and Marie vanRensberg, MB. At IVAC Corp: Walter Bochenko, BSEE, MBA, Robert Butterfield, BSEE, Douglas Christian, RPh, MBA, Alan Davison, BS, David Doan, PhD, Alan Somerville, BSEE, MS, Robin Wernick, BSEE, MS. 相似文献
88.
Autoantibodies against bactericidal/permeability-increasing protein in patients with cystic fibrosis 总被引:5,自引:0,他引:5
Zhao MH; Jayne DR; Ardiles LG; Culley F; Hodson ME; Lockwood CM 《QJM : monthly journal of the Association of Physicians》1996,89(4):259-265
Cystic fibrosis (CF), a genetic disorder, is characterized by chronic
pulmonary infection/inflammation which leads to respiratory failure. The
presence of anti-neutrophil cytoplasmic autoantibodies (ANCA) has
previously been observed in the sera of patients with CF. In view of the
known relationship of ANCA with primary vasculitis and of their putative
pathogenetic role in these disorders, we studied the presence, specificity
and isotype of ANCA and their clinical associations in 66 adult CF
patients. None of the 66 CF samples had autoantibodies to the major ANCA
antigens, proteinase 3 or myeloperoxidase. However, 60/66 (91%) CF samples
contained IgG and 55/66 (83%) IgA, autoantibodies to
bactericidal/permeability increasing protein (BPI), a recently
characterized ANCA specificity. All the IgA anti-BPI-positive samples were
also IgG anti-BPI-positive. The autoantibody specificity was confirmed by
inhibition assay and immunoblotting of CF sera against a neutrophil granule
preparation. Furthermore, in this cross-sectional study, anti-BPI levels
were inversely correlated with the observed reductions in FEV1 and FVC (IgA
anti-BPI and FEV1: r = 0.508, <it>p</it> < 0.0001), and
both IgG and IgA anti-BPI levels were higher in CF patients with secondary
vasculitis (<it>n</it> = 6) than in those without
(<it>p</it> < 0.05). ANCA with specificity for BPI were
present in the majority of CF sera in this study and autoimmune processes
may be associated with the development of pulmonary injury in CF.
相似文献
89.
Miers M 《Nurse education today》2002,22(3):212-219
Nurse education is established in higher education but nurse academics remain concerned about nursing's lack of equal status within the academy. This paper reports findings of a small study of nurse lecturers' views which support other published studies. It argues that cultural factors which contribute to nursing's problems gaining equal status include anti-intellectualism within nursing and academic denigration of practice. These cultural factors are linked to the history of women in higher education, the separation between intellectual education and practical, skill-based training, the low status of caring courses and the resulting mutual denigration of culturally opposed groups. Anti-intellectualism in nursing can be seen as a defensive reaction against an academic culture that defines practical activity as inferior to abstract thinking skills. This can lead to limited educational opportunities to examine the structural and cultural context of nursing. In Freire's view, this is a necessary part of education for freedom. Current cultural change, in nursing and higher education, including an emphasis on learning outcomes and transferable skills, provides new opportunities for nursing to contribute to educational change. Removing cultural barriers to the educated nurse is a responsibility shared by universities and by the nursing profession. 相似文献
90.
The authors developed quantitative radioimmunoassays to allow direct measurement of total human IgG and individual IgG subclasses among antibodies bound to cell surfaces. The assays use four mouse monoclonal radioiodinated antibodies, one that reacts equally well with all four human IgG subclasses and three that are specific for human IgG subclasses 1, 2, or 3. The assays were used to analyze IgG subclass composition in 21 high-titer anti-D samples from Rh-negative volunteers immunized for Rh immunoglobulin production. Anti-D activity was restricted primarily to the IgG1 and IgG3 subclasses. Eleven of 21 sera demonstrated red cell antibodies with a marked predominance of IgG1 (87 +/- 3.6% of total IgG antibody, +/- SEM) and low levels of IgG3 (1.4 +/- 0.73%). In the remaining 10 sera, IgG3 made up a greater proportion of total IgG antibody (32 +/- 3.8%), although IgG1 was still predominant (61 +/- 4.1%). This observed dichotomy in the IgG subclass profiles of different anti-D sera may be a consideration in the selection of anti-D sera for the production of the immunoglobulin used in the prophylaxis of Rh-incompatible pregnancies. 相似文献