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P F Rogers G A Head Y K Lungershausen P R Howe 《Journal of the autonomic nervous system》1991,34(1):9-16
The potential role of adrenaline, both circulating and in the central nervous system, in the maintenance of high blood pressure was examined in stroke-prone spontaneously hypertensive rats (SHRSP). alpha-Monofluoromethyldopa, a long-lasting inhibitor of dopa decarboxylase, was used to induce rapid depletion of central and peripheral catecholamine stores. Subsequent inhibition of phenylethanolamine-N-methyltransferase (PNMT) allowed the gradual restoration of dopamine and noradrenaline but not adrenaline, resulting in a greater relative depletion of adrenaline. Adrenaline was almost totally depleted in the circulation and peripheral tissues. The resting level of blood pressure, however, was unaffected, excepting after administration of a vasopressin (AVP) antagonist. Moreover, there was no reduction in the magnitude of acute pressor responses to electrical stimulation of the rostral ventrolateral medulla oblongata (C1 area), despite extensive loss of adrenaline from the brainstem and spinal cord. The results suggest that adrenaline contributes to the resting level of blood pressure but that its loss can be offset by the pressor activity of AVP. Thus neither central nor peripheral adrenaline stores appear to be essential for the maintenance of hypertension or for centrally-evoked vasoconstriction in adult SHRSP. 相似文献
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Daniel K. Howe Michael H. Vodkin Robert J. Novak Govinda Visvesvara G. L. McLaughlin 《Parasitology research》1997,83(4):345-348
Species-level identification of Acanthamoeba isolates is difficult and gives little or no indication of the isolate's pathogenicity. We identified two amplification-based genetic markers that were highly correlated with pathogenicity in Acanthamoeba spp. One marker, designed to amplify a 485-bp fragment of the small-subunit ribosomal RNA gene (ssrDNA), was preferentially amplified from the nonpathogenic strains; amplifications from the pathogenic strains yielded anomalous fragments of 650 and 900?bp. A second marker was developed on the basis of the anomalous 650-bp fragment. Primers to this sequence preferentially amplified a noncoding locus (called Ac6) only from the pathogenic strains. These two genetic markers may be useful for identification of pathogenic Acanthamoeba spp. strains. 相似文献
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A randomized controlled trial of antibiotics on symptom resolution in patients presenting to their general practitioner with a sore throat.
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R W Howe M R Millar J Coast M Whitfield T J Peters S Brookes 《The British journal of general practice》1997,47(418):280-284
BACKGROUND: Sore throat is a common symptom presented to general practitioners (GPs), and there remains controversy about the appropriate use of antibiotics. AIM: To compare, in a randomized controlled trial, the effectiveness of penicillin, cefixime and placebo on symptom resolution in patients presenting with a sore throat in general practice. METHOD: Twenty-two GPs in Avon recruited 154 patients, aged 16-60 years, presenting to their GP with a sore throat, and for whom the GP would normally prescribe an antibiotic. Patients were randomized to one of three groups: penicillin V 250 mg four times a day; cefixime 200 mg daily; and placebo. Each was prescribed for five days. The main outcome measures were a diary of symptom resolution over seven days and eradication of group A beta-haemolytic streptococcus (GABHS). RESULTS: Of the 103 (67%) patients who completed symptom diaries, 40 were allocated to receive penicillin, 29 cefixime and 34 placebo. In the analysis including all patients, symptom resolution was greater by day 3 in the cefixime group than in the placebo group. Penicillin did not improve symptom resolution by day 3 compared with placebo, and cefixime was not statistically significantly different from penicillin. There were significant differences in the proportion of patients using analgesia at day 3, with the proportion being lowest in the cefixime group. The results for the subgroup of patients without GABHS were similar to those for all patients; in particular, the only statistically significant difference was between cefixime and placebo. Although numbers were too small for statistical significance, among patients with GABHS the effects of penicillin and cefixime were similarly raised in relation to placebo. CONCLUSION: Compared with placebo, cefixime can improve the rate of resolution of symptoms in patients with a sore throat who are selected for antibiotic treatment by their GP. The unexpected finding that cefixime was of benefit compared with placebo for patients without GABHS suggests that bacteria other than GABHS may be important in the pathogenesis of sore throat. 相似文献
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Laura L S Howe Ashton M Anderson David A S Kaufman Bonnie C Sachs David W Loring 《Archives of clinical neuropsychology》2007,22(6):753-761
We prospectively evaluated performance of 63 referrals to a memory disorders clinic who received the Medical Symptom Validity Test (MSVT) as part of their standard neuropsychological evaluation. The patients were grouped based on independent medical diagnoses and presence or absence of a potential financial incentive to under-perform. Twenty-seven patients (42.9%) scored below cutoffs on the MSVT symptom validity indices. Two individuals in the potential financial incentive group showed clear signs of invalid responding (18.2%). Twenty-two of the remaining 25 patients who failed the symptom validity indices corresponded to the dementia profile. Three individuals did not correspond to the dementia profile but are thought to have performed validly representing a 4.8% false positive rate. When considering all MSVT indices, the base rate of invalid responding in the potential financial incentive to under-perform group increased to 27.3%. Combining all groups our base rate of invalid responding was 4.8%. Specific performances are presented. 相似文献
9.
Midazolam sedation for outpatient fibreoptic endoscopy: evaluation of alfentanil supplementation. 总被引:1,自引:0,他引:1
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K. R. Milligan J. P. Howe J. McLoughlin W. Holmes J. W. Dundee 《Annals of the Royal College of Surgeons of England》1988,70(5):304-306
Alfentanil, a short-acting opioid, was used as an adjuvant to midazolam for sedation of 30 outpatients undergoing upper gastrointestinal endoscopy. The operating conditions and recovery times were compared with those of a similar group of 30 patients sedated with midazolam only. The use of alfentanil resulted in improved operating conditions and a more rapid recovery. Patient acceptance was high. 相似文献
10.
Ten thrombocytopenic patients (platelets < 10–24 × 10(9)/L) who were refractory to platelet transfusion were investigated for their responsiveness to staphylococcal protein A column therapy. Nine patients had previously been treated with steroids, intravenous immune globulin, and/or other forms of immunosuppressive therapy without improvement in their transfusion response. All patients were receiving multiple platelet transfusions without achieving 1-hour corrected count increments (CCIs) > or = 7500. Eight patients had antibodies that reacted with platelets and were directed against HLA class I antigens, ABO antigens, and/or platelet-specific alloantigens. Plasma (500-2000 mL) from each patient was passed over a protein A silica gel column and then returned to the patient. Patients received from 1 to 14 treatments. A positive response to protein A therapy was defined as at least a doubling of the pretreatment platelet count and/or two successive 10- to 120-minute posttransfusion CCIs > or = 7500. Following plasma treatments, 6 of 10 patients responded with daily platelet counts that averaged 48 +/− 11 × 10(9) per L as compared with counts of 16 +/− 7 × 10(9) per L (p < 0.0005) before treatment. Posttransfusion CCI values determined in four of these patients averaged 2480 +/− 810 and 10,010 +/− 3540 (p < 0.005) before and after treatment, respectively. In contrast, among the four unresponsive patients, platelet counts averaged 10 +/− 9 and 13 +/− 10 × 10(9) per L (p = NS), respectively, while posttransfusion CCIs were 700 +/− 1410 and 1520 +/− 2460 (p = NS), respectively.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献