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61.
62.
Computed tomographic (CT) scans are performed on virtually all patients with severe head injury at the time of admission. Because of the time involved in obtaining these studies, the evacuation of significant intracranial mass lesions is delayed. To avoid such delays, the authors performed burr-hole exploration for the diagnosis of intracranial hematomas before CT scans were obtained in 100 consecutive head-injured patients with clinical signs of tentorial herniation or upper brain stem dysfunction upon admission to the emergency room. Patients in whom a hematoma was discovered had a craniotomy for evacuation of the clot; those in whom the exploration was negative had a CT brain scan immediately after operation. Burr-hole exploration revealed extracerebral mass lesions in 56 patients. In 38 patients, the exploration was negative, and postoperative CT scanning showed no significant hematoma. Of 6 patients in whom the CT scan demonstrated extraaxial hematomas requiring surgical evacuation, 4 had subdural hematomas that were missed because the exploration was incomplete; 1 patient had an epidural hematoma and 1 had a subdural hematoma contralateral to a craniotomy on the side of a positive initial burr-hole exploration. Our results indicate that the relatively small subgroup of head-injured patients with early tentorial herniation or upper brain stem compression have a high incidence of immediate extraaxial hematomas and a low incidence of intracerebral hematomas. This is particularly true of patients over 30 years of age and those who suffer low speed trauma, such as falls and vehicle-pedestrian accidents. 相似文献
63.
Galega officinalis L (goatsrue), a plant introduced from Europe and found in abundance in northern Utah, was tested for toxicity in ewes (Ovis aries). Clinical signs of poisoning induced by doses as small as 0.8 g of dried plant/kg body weight/day included dyspnea, anoxia, and foaming nasal discharge. Pathologic signs in animals that died following overdose of the plant included severe hydrothorax, generalized lung congestion, foamy exudate in bronchioles and trachea, epicardial and endocardial petechiation, and pericardial effusion in severely affected ewes. Microscopic lesions included a severe diffuse alveolar and interlobular edema. No significant alterations in blood constituents were observed in treated animals. Ewes administered the plant on several consecutive days developed an apparent adaptation to the toxin of the plant and were thereby able subsequently to tolerate levels 5-10 times the pre-treatment lethal dose with no discernible adverse clinical or pathological effects. 相似文献
64.
Stuart J. McLachlan John C. Francisco Joseph R. Pernicone Anton N. Hasso 《Journal of magnetic resonance imaging : JMRI》1994,4(3):405-411
A phase III multicenter study was conducted in 89 patients with known intracranial vascular lesions to evaluate an extracellular gadolinium contrast agent, gadoteridol, for intracranial magnetic resonance (MR) angiography. The pre- and postcontrast MR angiograms of 82 patients were evaluated by the unblinded investigators and by two blinded readers (A and B) for visualization of lesions; arterial and venous anatomy; extent, size, and number of lesions; and disease classification. The unblinded readers indicated that lesions were visualized better on postcontrast images in the following categories: venous anatomy, 87 (81%) of 107 lesions; arterial anatomy, 43 lesions (40%); and extent or size of lesions, 38 lesions (36%). In 29 (35%) of 82 patients, the unblinded readers determined that enhanced MR angiography provided more diagnostic information than unenhanced MR angiography. The blinded readers determined that enhanced MR angiography provided more information for visualization of vascular anatomy in more than 60% of cases. The additional information provided with gadoteridol would have changed the diagnosis in nine (8%) of 107 lesions seen by the unblinded readers, 11 (12%) of 90 lesions seen by reader A, and three (3%) of 93 lesions seen by reader B. The results confirm that the use of gadoteridol improves the visualization of intracranial vascular lesions with MR angiography. The authors conclude that development of new postprocessing algorithms will improve the utility of contrast-enhanced MR angiography. 相似文献
65.
Sneyd J. R.; Wright PMC.; Cross M.; Thompson P.; Voortman G.; Weideman M. M.; Andrews CJH.; Daniell C. J. 《British journal of anaesthesia》1997,79(4):427-432
Ten male volunteers received a 1-min i.v. infusion of a new water soluble
steroid anaesthetic agent, ORG 21465. Individuals received doses ranging
from 0.8 to 1.8 mg kg-1. All subjects experienced venous pain at the site
of injection; those receiving 1.0 mg kg-1 or more became anaesthetized.
There was no evidence of histamine release and apnoea did not occur.
Excitatory phenomena were observed in all subjects and were dose related;
no spikes were seen on the EEG. Pharmacokinetic analysis supported a
three-compartment (non-weight- related) model with compartmental volumes
V1, V2 and V3 of 4.31, 14.2 and 89.4 litre, respectively. Clearance from
the central compartment V1 was 1.55 litre min-1. Inter-compartmental
clearances Q1 and Q2 were 2.54 and 1.79 litre min-1. We found that ORG
21465 was an effective anaesthetic in humans. The relationship between
sedation, anaesthesia and excitation requires further exploration.
相似文献
66.
67.
68.
Nigel Wynne RGN/Dip BSc Stuart Brand BSc PhD Roy Smith BA PhD 《Journal of advanced nursing》1997,26(3):470-474
There is an ongoing debate in nurse education concerning the role and delivery of the biological sciences in the nursing curriculum. One of the fundamental questions raised by this debate asks how best can teachers impart biological knowledge in a manner that can be readily applied by students and qualified nurses to inform their clinical practice. This paper will include a discussion of some of the features of pre-registration education that may have influenced the manner in which biological sciences are perceived, taught and used by nurses. It will be argued that nursing may have developed a form of incomplete holism and that this may be in part responsible for the challenges that remain to be met within this area of the nursing curriculum. As a response to incomplete holism an innovative approach within pre-registration education will be introduced. This development involves the use of linked teaching sessions which aim to develop the analytical skills necessary to apply physiological knowledge to nursing practice. 相似文献
69.
70.
Stuart Jon Spechler 《Clinical gastroenterology and hepatology》2003,1(2):81-88
This review critically appraises the evidence on the benefits and costs of the available treatments for gastroesophageal reflux disease (GERD) and concludes that antireflux surgery has no clear advantages over medical therapy for efficacy of healing, prevention of complications, safety, side effects, and cost. Indeed, medical therapy is safer and, probably, more cost-effective. Compared with medically treated patients, those who have successful fundoplication may be less inconvenienced by GERD because they are less likely to need to take pills on a daily basis. The patient and physician must judge whether that benefit justifies the risks of surgery for a benign condition. There is not yet sufficient data available on the endoscopic antireflux procedures to make meaningful conclusions regarding their safety and efficacy. 相似文献