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排序方式: 共有615条查询结果,搜索用时 15 毫秒
1.
PRO 1000 V3型心电监护仪LCD逆变器的升级及注意事项 总被引:1,自引:0,他引:1
介绍了该型心电监护仪黑屏故障的常见原因,对升级前后的LCD逆变器电路作了对比分析,并详细介绍了升级更换的方法和注意事项。 相似文献
2.
Adam S Hassan Mark W Johnson Todd E Schneiderman Carl D Regillo Paul E Tornambe Lon S Poliner Barbara A Blodi Susan G Elner 《Ophthalmology》1999,106(10):1900-1907
Objective
To investigate the efficacy and safety of treating thick submacular hemorrhages with intravitreous tissue plasminogen activator (tPA) and pneumatic displacement.Design
Retrospective, noncomparative case series.Participants
From 5 participating centers, 15 eligible patients had acute (<3 weeks) thick subretinal hemorrhage involving the center of the macula in eyes with pre-existing good visual acuity. Hemorrhages were secondary to age-related macular degeneration in 13 eyes and macroaneurysm and trauma in 1 eye each.Methods
The authors reviewed the medical records of 15 consecutive patients who received intravitreous injection of commercial tPA solution (25–100 μg in 0.1–0.2 ml) and expansile gas (0.3–0.4 ml of perfluoropropane or sulfur hexafluoride) for thrombolysis and displacement of submacular hemorrhage. After surgery, patients maintained prone positioning for 1 to 5 days (typically, 24 hours).Main outcome measures
Degree of blood displacement from under the fovea, best postoperative visual acuity, final postoperative visual acuity, and surgical complications.Results
In 15 (100%) of 15 eyes, the procedure resulted in complete displacement of thick submacular hemorrhage out of the foveal area. Best postprocedure visual acuity improved by 2 lines or greater in 14 (93%) of 15 eyes. After a mean follow-up of 10.5 months (range, 4–19 months), final visual acuity improved by 2 lines or greater in 10 (67%) of 15 eyes and measured 20/80 or better in 6 (40%) of 15 eyes. Complications included breakthrough vitreous hemorrhage in three eyes and endophthalmitis in one eye. Four eyes developed recurrent hemorrhage 1 to 3 months after treatment, three of which were retreated with the same procedure.Conclusions
Intravitreous injection of tPA and gas followed by brief prone positioning is effective in displacing thick submacular blood and facilitating visual improvement in most patients. The rate of serious complications appears low. Final visual outcomes are limited by progression of the underlying macular disease in many patients. 相似文献3.
D M Jacobson 《Ophthalmology》1999,106(10):1994-2004
OBJECTIVE: To characterize the clinical features and course of patients with magnetic resonance imaging (MRI)-defined optic nerve compression by the supraclinoid carotid artery. DESIGN: Retrospective, observational case series. PARTICIPANTS: Eighteen patients with 24 affected eyes were identified by reviewing case records from the author's referral-based neuro-ophthalmology practice. Predetermined inclusion and exclusion criteria were applied to potential participants. MAIN OUTCOME MEASURES: The following variables were abstracted from the medical record: age, gender, presenting symptoms, past medical problems, visual acuity, color vision, visual field, pupillary reactions, optic disc appearance, other neurologic signs, and previously documented and follow-up examinations. RESULTS: There were eight women and ten men ranging in age from 28 to 86 years (median age, 72 years) at the time of diagnosis. Ten (56%) of 18 patients had hypertension. Twelve patients had unilateral optic neuropathy, whereas 6 patients had bilateral optic neuropathy. One patient presented with subacute superior orbital fissure syndrome due to mass effect of a dolichoectatic carotid artery. Another patient had oculomotor nerve palsy with signs of aberrant regeneration due to intracavernous mass effect of a dolichoectatic carotid artery. One patient had a bitemporal hemianopia associated with bilateral compression of the immediate prechiasmatic optic nerves by dolichoectatic carotid arteries. The predominant pattern of visual field loss in most patients reflected nerve fiber bundle injury. A central scotoma or absolute central visual field loss was noted in only 6 (25%) of 24 affected eyes. Most patients demonstrated saucerlike excavation of the optic disc. Progression of visual acuity loss occurred at a relatively slow rate. CONCLUSIONS: Although uncommon, intracranial compression of the optic nerve by the carotid artery should be considered in a patient with unexplained or progressive unilateral or bilateral optic neuropathy. This entity can be diagnosed using clinical skills to exclude more common causes of optic nerve injury and coronal-oriented MRI to confirm anatomic compression of the symptomatic optic nerve. Although many affected patients have excavation of the optic disc and nerve fiber bundle visual field defects, most have additional signs atypical for glaucoma, minimizing the potential for diagnostic confusion between the two disorders. 相似文献
4.
The work presents a detailed comparison of calculated and experimentally determined net peak areas of longer-living fission products after 100 h irradiation on a reactor with power of ~630 W and several days cooling. Specifically the nuclides studied are 140Ba, 103Ru, 131I, 141Ce, 95Zr. The good agreement between the calculated and measured net peak areas, which is better than in determination using short lived 92Sr, is reported.The experiment was conducted on the VVER-1000 mock-up installed on the LR-0 reactor. The Monte Carlo approach has been used for calculations. The influence of different data libraries on results of calculation is discussed as well. 相似文献
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7.
The call for transformation of nursing education and practice continues to be a national priority. The American Association of Colleges of Nursing recommends enhanced partnerships between academic nursing and academic health centers to advance nursing and healthcare. For academic leaders in rural settings, the context of health and healthcare means that these partnerships are vastly different from academic health centers. The purpose of this article is to describe the context of nursing education and practice in regions that are predominantly rural. The challenges and opportunities for rural academic leaders as they respond to calls for transforming the education of the future nursing workforce are described from the perspective of resources, recruitment and retention of faculty, clinical education and faculty practice, scholarship, and fundraising. Meeting rural health workforce needs is a national imperative and a priority of academic nursing leaders in rural settings. 相似文献
8.
目的:比较UF-1000i尿沉渣分析仪与尿沉渣显微镜两种检查方法在尿液管型检测中的优缺点。方法收集600例患者的尿液标本,用UF-1000i尿沉渣分析仪与显微镜两种仪器检测尿沉渣中的管型,比较分析结果。结果 UF-1000i尿沉渣分析仪检测尿中管型的检出率为12.7%,特异度为94.9%,灵敏度为92.3%,假阴性率5.1%,假阳性率7.7%;尿沉渣显微镜检查尿中管型的阳性率为8.7%。结论 UF-1000i尿沉渣分析仪检测尿中管型时存在较多的假阳性和假阴性,如果将尿沉渣分析仪与显微镜检查联合应用,可以提高管型检测的准确率,为临床诊断提供可靠依据。 相似文献
9.
The timing of the early metabolic, ionic, and secretory responses to glucose in rat pancreatic islets was monitored by measuring, at 12 sec intervals, the concentrations of glucose, lactic, and pyruvic acids, 32P, 86Rb, 45Ca, and insulin in the effluent of perifused prelabeled islets. The increase in glucose concentration from zero to 16.7 mM was complete within 133 sec. The output of organic acids increased after 24 sec of exposure to glucose and, in the case of lactic acid, fell slightly after the initial elevation. The phosphate flush was initiated only after 96 sec of exposure to glucose, whereas the decreases in 86Rb and 45Ca outflow were both detectable within 72 sec of stimulation. The secondary rise in 45Ca efflux was first seen after 157 sec of stimulation and its time course was not vastly different from that of insulin release. These data indicate that, in the secretory sequence, metabolic changes precede both the remodelling of ionic fluxes and the stimulation of insulin release. The results are compatible with the view that the secondary rise in 45Ca outflow is attributable, in part at least, to the glucose-induced decrease in K conductance (but not to the increase in phosphate outflow), with resulting membrane depolarization and gating of voltage-dependent Ca channels. 相似文献
10.
Volker Kötter Klaus-Peter Schüren Rolf Schröder 《The American journal of cardiology》1978,42(4):563-569
In 10 patients with chronic coronary artery disease and without clinical evidence of congestive heart failure, the effects of 1.0 mg of digoxin intravenously on systemic hemodynamics, coronary blood flow, myocardial oxygen consumption and myocardial lactate extraction were studied both at rest and during atrial pacing. Atrial stimulation at a rate just below the threshold for angina led to a significant decrease in left ventricular enddiastolic pressure, from 10.6 ± 1.6 to 7.1 ± 0.8 mm Hg, associated with a significant decrease in left ventricular stroke work index per beat, from 76.7 ± 5.11 to 40.3 ± 4.01 g-m/m2. After digoxin, nearly identical results in stroke work index could be observed at rest and during stimulation (75.2 ± 6.74 and 44.1 ± 5.92, respectively). However, left ventricular enddiastolic pressure decreased significantly before and during atrial stimulation (8.1 ± 1.29 and 4.7 ± 1.09 mm Hg, respectively). Cardiac index decreased from 3.08 ± 0.20 to 2.73 ±0.17 liters/min per m2 at rest but during pacing it no longer differed before and after digoxin (3.17 ± 0.22 and 3.10 ± 0.20 liters/min per m2, respectively). Myocardial oxygen consumption and lactate extraction remained unchanged after digoxin both at rest and during atrial pacing.It is concluded that some deficiency in left ventricular function is present in patients with chronic coronary artery disease even without clinical evidence of congestive heart failure. Digoxin improves left ventricular performance at rest and during stress conditions. An expected increase in myocardial oxygen consumption due to enhanced contractility is completely counterbalanced, probably by a decrease in left ventricular volume after digoxin. 相似文献