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991.
J. M. Johnston P. Grondziowski R. M. Windisch R. A. Eder L. Lytle 《Acta diabetologica》1995,32(4):213-216
A feasibility study was undertaken to evaluate laboratory phlebotomists performing bedside glucose monitoring (BGM) over a
3-month period on a medical and surgical floor. Specific questions included: feasibility of providing testing on a 24-h basis,
accuracy, appropriate utilization, effect on patient care, and an analysis of cost. In all, 1975 tests were performed on 114
patients. BGM results were within 15% of the laboratory's result 97% of the time. Patient and physician satisfaction was high.
Although the cost of BGM is slightly higher than a laboratory glucose test, its use appeared to reduce the length of hospital
stay by 0.47 days. Practical information on initiating a highly successful BGM program is provided. 相似文献
992.
Recent reports suggest that oxygen radical-induced lipid peroxidation plays a role in the retrograde degeneration of motor neurons following facial nerve axotomy in the neonatal rat. The purpose of the present study was to explore this notion further by testing the neuroprotective properties of two novel brain-penetrating, lipid peroxidation inhibitors, U-101033E and U-104067F, in this model of neuronal degeneration. In Experiment 1, 14-day-old rats were pretreated with 3, 10, or 30 mg/kg U-101033E (po) 10 min before right facial nerve axotomy (Day 0) and then posttreated once a day from Day 1 to Day 6, and once every other day from Day 8 to Day 21. Rats were sacrificed 21 days postaxotomy and surviving cholinergic cell bodies were identified using choline acetyltransferase immunocytochemistry. Both 10 and 30 mg/kg U-101033E significantly enhanced motor neuron survival, with survival rates of 65.9–88.9% being noted in comparison to 51.7–62% survival in vehicle controls (P ≤ 0.05). Experiment 2 demonstrated a significant neuroprotective effect of 10 and 30 mg/kg U-104067F using the same dosing schedule. Experiment 3 was designed to test whether shorter periods of drug exposure (e.g., 5 or 7 days) would be sufficient to preserve motor neurons in rats treated with 10 mg/kg U-101033E. The results suggested that as little as 5 days of drug treatment is sufficient to enhance motor neuron survival. Finally, Experiment 4 demonstrated an 18–19% increase in motor neuron survival in rats treated with 10 and 30 mg/kg U-104067F for 5 consecutive days postaxotomy. Taken together, the attenuation of motor neuron degeneration by the two pyrrolopyrimidine lipid peroxidation inhibitors, U-101033E and U-104067F, lends support to the notion that lipid peroxidation contributes to the pathogenesis of axotomy-induced neurodegeneration. 相似文献
993.
994.
J. de Pedro-Cuesta V. Abraira G.-X. Jiang G. Solders S. Fredrikson 《Acta neurologica Scandinavica》1996,93(2-3):175-183
Using hierarchical cluster analysis, applied to 47 cases of Guillain-Barre Syndrome (GBS) incident in South-West Stockholm (SWS) during the period from January 1973 to June 1992, we identified three major clinicoepidemiological subgroups. The first subgroup, 25.5% of the cases (26.7 ± 6.7 years), recorded a peak incidence at ages 20–29 years and presented significant differences from other subgroups, a high proportion of cases with onset at low age preceded by respiratory infection (83.3%) and with normal motor conduction velocity (50.0%). Also found, were less affected biological parameters, a rapidly progressive course and independence in gait at one month after onset. A second subgroup, 27.7% of cases, was severely affected, clinically and functionally. It consisted predominantly of young individuals (22.7 ± 11.1 years), with a high incidence (69.2% of cases) in autumn. A third subgroup, comprising 40.47; of cases, was older (61.1 ± 11.0 years) and, in general, also severely affected. The incidence of this form appeared to be invariant with time. 相似文献
995.
The effect of oxygen free radicals on calcium current and dihydropyridine binding sites in guinea-pig ventricular myocytes.
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L. Guerra E. Cerbai S. Gessi P. A. Borea A. Mugelli 《British journal of pharmacology》1996,118(5):1278-1284
1. We used electrophysiological and binding techniques to determine the effects of oxygen free radicals (OFRs) generated by dihydroxyfumaric acid (DHF, 5 mM) on calcium current and dihydropyridine binding sites in guinea-pig isolated ventricular myocytes. 2. Binding of [3H]-PN200-110 to isolated ventricular myocytes revealed one population of binding sites with a KD of 0.11 +/- 0.01 nM and Bmax of 139.1 +/- 6.9 fmol mg-1 protein (n = 24). After 15 min of exposure to DHF, the density, but not the affinity of [3H]-PN200-110 binding sites was significantly (P < 0.01) reduced to 35% of the control value (Bmax = 49.4 +/- 3.7 fmol mg-1 protein, KD = 0.11 +/- 0.01 nM, n = 15). In the presence of superoxide dismutase (SOD) and catalase (CAT) the reduction in [3H]-PN200-110 binding sites was almost completely prevented (Bmax = 120.5 +/- 7.4 in control, n = 4 and 98.8 +/- 7.4 fmol mg-1 protein in DHF plus SOD and CAT, n = 4). KD values were not modified (0.08 +/- 0.01 in control and 0.09 +/- 0.01 nM in DHF plus SOD and CAT). 3. The time-course of the reduction of [3H]-PN200-110 binding sites by OFRs was paralleled by the decrease in L-type calcium current (Ica,L) measured in patch-clamped guinea-pig ventricular myocytes either in the absence or in the presence of EGTA in the patch pipette. In the former conditions OFRs induced the appearance of calcium-dependent alterations, i.e. the transient inward current, within 10 min. After 30 min of incubation with DHF, [3H]-PN200-110 binding sites were reduced to 25% of the control value. 4. In myocytes incubated with the antilipoperoxidant agent, butylated hydroxytoluene (BHT, 50 microM), the decrease in [3H]-PN200-110 binding sites caused by DHF was partially prevented (Bmax values after 30 min exposure to DHF were 55.5 +/- 1.9 and 23.7 +/- 5.9 fmol mg-1 protein in the presence and in the absence of BHT respectively, P < 0.05). BHT did not affect the decrease in [3H]-PN200-110 binding sites during the first 15 min of exposure to DHF, but was able to prevent completely the further decrease occurring during the following 15 min of incubation with OFRs. 5. Our results demonstrate that the OFR-induced decrease in calcium current is associated with a reduction in DHP binding sites. The decrease in calcium current and in calcium channels may be implicated in the mechanical dysfunction associated with oxidative stress. 相似文献
996.
997.
998.
A. G. D. Maran J. A. Wilson M. N. Gaze 《European archives of oto-rhino-laryngology》1993,250(3):127-132
Summary Squamous cell carcinoma of the head and neck is a disease predominantly of males and is due to a variety of known environmental irritants, notably cigarette smoke. Dietary, viral and immunological factors may also be relevant. Head and neck squamous cancers express epidermal growth factor receptors and some show weak levels of oestrogen receptor activity, but a reliable serum marker of tumour burden remains to be identified. The prognosis is found to be less favourable in females, in those with advanced T stage, in association with multiple node involvement, especially where extracapsular spread is present and where the T4/T8 ratio is elevated. Administration of heterologous blood during therapy may also have an adverse effect on prognosis. Interested clinicians must remember that most cases are preventable.
Correspondence to: A.G.D. Maran 相似文献
999.
Carlo La Vecchia Silvia Franceschi Ettore Bidoli Fabio Barbone Piero Dolara 《International journal of cancer. Journal international du cancer》1993,55(3):386-389
The relationship between sugar added to coffee and other hot beverages--as an indicator of taste for sugar and sugar intake outside main meals--and the risk of colorectal cancer was investigated using data from a case-control study conducted in Northern Italy on 953 cases of histologically confirmed colon cancer, 633 of rectal cancer and 2845 controls admitted to hospital for acute, non-neoplastic, non-digestive tract disorders. Compared with subjects who reported adding no sugar to their beverages, the multivariate relative risks (RR) of colon cancer were 1.4 for those adding one spoonful of sugar, 1.6 for those adding 2 spoonsful, and 2.0 for those adding 3 or more. The corresponding RRs for rectal cancer were 1.3, 1.5 and 1.4. For combination of colorectal cancer the RRs were 1.4, 1.5 and 1.8. All the trends in risk were significant, and the results were consistent across strata of study centre, sex and age, and were not appreciably modified by allowance for a number of major identified potential distorting factors, including an estimate of total calorie intake. These findings, if confirmed, would suggest that taste for sugar is a relevant indicator of colorectal cancer risk, and could be interpreted either in terms of a role of sugar in colorectal carcinogens, or of a specific influence of even limited amounts of sugar taken outside meals, which may stimulate the proliferation of the bowel epithelium, and hence enhance colorectal carcinogenesis. 相似文献
1000.
B L Bower D Picus M E Hicks M D Darcy E S Rollins M A Kleinhoffer P J Weyman 《Journal of vascular and interventional radiology : JVIR》1990,1(1):107-112
Retained biliary stones remain a common clinical problem in patients after surgery. Since 1984, the authors have used choledochoscopy in the treatment of suspected retained biliary stones in 75 patients. These procedures were performed in the radiology department with use of local anesthesia supplemented by an intravenously administered sedative and analgesic. A 15-F flexible fiberoptic choledochoscope was used. Fifty-one of the 75 patients were treated as outpatients. Treatment was successful in 74 of 75 patients; in one patient, intrahepatic stones were not completely removed. Electrohydraulic lithotripsy was used to fragment calculi in 11 patients (15%). Biopsies were performed in four patients (5%). Five minor complications occurred; three required overnight admission. Choledochoscopic-assisted removal of retained biliary calculi is a highly effective and safe procedure. Advantages over standard fluoroscopic stone removal include the ability to directly visualize and fragment adherent or impacted stones and visualize noncalculous filling defects, such as air bubbles, mucus, and biliary tumors. 相似文献