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排序方式: 共有835条查询结果,搜索用时 15 毫秒
91.
R Curtis JR Tonra JL Stark KM Adryan JS Park KD Cliffer RM Lindsay PS DiStefano 《Canadian Metallurgical Quarterly》1998,12(3):105-118
We investigated the retrograde axonal transport of 125I-labeled neurotrophins (NGF, BDNF, NT-3, and NT-4) from the sciatic nerve to dorsal root ganglion (DRG) sensory neurons and spinal motor neurons in normal rats or after neuronal injury. DRG neurons showed increased transport of all neurotrophins following crush injury to the sciatic nerve. This was maximal 1 day after sciatic nerve crush and returned to control levels after 7 days. 125I-BDNF transport from sciatic nerve was elevated with injection either proximal to the lesion or directly into the crush site and after transection of the dorsal roots. All neurotrophin transport was receptor-mediated and consistent with neurotrophin binding to the low-affinity neurotrophin receptor (LNR) or Trk receptors. However, transport of 125I-labeled wheat germ agglutinin also increased 1 day after sciatic nerve crush, showing that increased uptake and transport is a generalized response to injury in DRG sensory neurons. Spinal cord motor neurons also showed increased neurotrophin transport following sciatic nerve injury, although this was maximal after 3 days. The transport of 125I-NGF depended on the expression of LNR by injured motor neurons, as demonstrated by competition experiments with unlabeled neurotrophins. The absence of TrkA in normal motor neurons or after axotomy was confirmed by immunostaining and in situ hybridization. Thus, increased transport of neurotrophic factors after neuronal injury is due to multiple receptor-mediated mechanisms including general increases in axonal transport capacity. 相似文献
92.
Lindsay F.G. Williams 《Corrosion Science》1979,19(7):767-775
A polarization curve around the corrosion potential has been obtained for zinc immersed in a near neutral solution by using a potentiostat controlled by a microcomputer. The polarization data was fitted by the microcomputer to the general electrochemical equation for a metal corroding in solution and this resulted in values for the corrosion rate and the Tafel parameters. The corrosion of zinc in a de-aerated sodium chloride solution at pH 5.3 was used to demonstrate the method. After 1 h immersion, the anodic and cathodic Tafel slopes approached constant values of 60 and 120 mV respectively. Rotating disc studies did not reveal any contribution from a diffusion controlled cathodic process. 相似文献
93.
RL Garnett A MacIntyre P Lindsay GG Barber CW Cole G Hajjar NV McPhail TD Ruddy R Stark D Boisvert 《Canadian Metallurgical Quarterly》1996,43(8):769-777
PURPOSE: The goal of this randomized study was to determine whether combined general and epidural anaesthesia with postoperative epidural analgesia, compared with general anaesthesia and postoperative intravenous analgesia, reduced the incidence of perioperative myocardial ischaemia in patients undergoing elective aortic surgery. METHOD: Patients were randomly assigned to one of two groups. One group (EPI, n = 48) received combined general and epidural anaesthesia and postoperative epidural analgesia for 48 hrs. The other group (GA, n = 51) received general anaesthesia followed by postoperative intravenous analgesia. Anaesthetic goals were to maintain haemodynamic stability (+/- 20% of preoperative values), and a stroke volume > 1 ml.kg-1. A Holter monitor was attached to each patient the day before surgery. Leads 11, V2, and V5 were monitored. Myocardial ischaemia was defined as ST segment depression > 1 mm measured at 80 millisec beyond the J point or an elevation of 2 mm 60 millisec beyond the J point which lasted > 60 sec. An event that lasted > 60 sec but returned to the baseline for > 60 sec and then recurred, was counted as two separate events. The Holter tapes were reviewed by a cardiologist blind to the patient's group. RESULTS: There were no demographic differences between the two groups. Myocardial ischaemia was common; it occurred in 55% of patients. In hospital, preoperative ischaemia was uncommon (GA = 3, EPI = 8). Intraoperative ischaemia was common (GA = 18, EPI = 25). Mesenteric traction produced the largest number of ischaemic (GA = 11, EPI = 11) events. Postoperative ischaemia was most common on the day of surgery. Termination of epidural analgesia produced a burst of ischaemia (60 events in 9 patients). CONCLUSION: Combined general and epidural anaesthesia and postoperative epidural analgesia do not reduce the incidence of myocardial ischaemia or morbidity compared with general anaesthesia and postoperative intravenous analgesia. 相似文献
94.
95.
Measurements of peak expiratory flow rate during serial exercise tests were used to assess the efficacy of the beta adrenergic stimulants oral terbutaline (5 mg) and fenoterol aerosol (400 micrograms), in preventing post-exercise bronchoconstriction in 18 asthmatic subjects. While both compounds significantly elevated resting levels of peak expiratory flow rate for at least four hours, there were qualitative and quantitative differences in the effects of the two drugs on exercise induced bronchoconstriction. Oral terbulation did not significantly alter the pattern of response to exercise. However, the peak expiratory flow rates before during and after exercise were significantly higher compared with placebo at two, four and six hours after the drug. The importance of examination of actual values for peak expiratory flow rates as well as percentage changes when testing oral bronchodilators is emphasised. Aerosol fenoterol completely blocked post-exercise bronchoconstriction immediately after inhalation and for up to four hours in most subjects. Bronchodilatation occurred in all subjects during exercise in the presence of both the active and placebo drugs. It is postulated that the superiority of the aerosol in blocking exercise induced bronchoconstriction may be function of its activity at the surface of the bronchial mucosa. 相似文献
96.
97.
A 56 year old patient with psychiatric complications of systemic lupus erythematosus developed severe dysphagia complicated by weight loss and aspiration. Following investigation it was concluded that the addition of haloperidol to her treatment was the major precipitating cause and withdrawal of the drug was followed by an objective improvement in swallowing. Patients taking major transquillizers may be at increased risk of severe dysphagia; regular observation of swallowing is suggested as a useful addition to the clinical examination of these patients. 相似文献
98.
Furstenberg Frank F.; Brooks-Gunn Jeanne; Chase-Lansdale Lindsay 《Canadian Metallurgical Quarterly》1989,44(2):313
This article reviews recent evidence on the changing patterns of childbearing among adolescents and the impact of premature parenthood on the life course of young mothers and their children. Although adolescent mothers experience conspicuous disadvantages in educational attainment and economic well-being, over time the differences between early and later childbearing appear to diminish somewhat, at least for Blacks. The children of teenage mothers, however, are distinctly worse off throughout childhood than the offspring of older childbearers. The reasons for this disparity are explored. The concluding section discusses a range of preventive and ameliorative strategies for reducing the cost of early childbearing. The evidence supports the need for more integration among services and the importance of increasing the availability of services to those in need. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
99.
100.
OBJECTIVE: To describe a patient in whom the administration of tiaprofenic acid and fosinopril was associated with decreased lithium clearance, resulting in increased serum lithium concentrations. CASE SUMMARY: A woman treated with lithium for bipolar affective disorder was concurrently treated with tiaprofenic acid 200 mg tid for shoulder pain. Previously initiated treatment with fosinopril was maintained during this time. The urinary lithium clearance was decreased during this combination therapy, necessitating a reduction in the lithium dosage. DISCUSSION: Lithium is approximately 80% reabsorbed in the proximal tubule, and the addition of tiaprofenic acid may have resulted in enhanced tubular lithium reabsorption. The possible influence of concurrent fosinopril therapy may also have contributed to altered lithium pharmacokinetics in this case. CONCLUSIONS: Serum lithium concentrations should be monitored if patients taking lithium are treated with tiaprofenic acid. 相似文献