摘要:

Nineteen unanesthetized sheep were given Evans blue dye or radionuclide and then were incrementally bled into hemorrhagic shock (BP less than 50/25) by withdrawal of blood orer a period of approximately one hour. Four sheep served as controls for histologic data. Static nuclide brain scans performed in 6 bled sheep demonstrated immediate uptake of the radionuclide. Fluorescence microscopic examination of brain tissue obtained at autopsy in bled sheep demonstrated dye uptake in the perirascular areas, but not in the neuropil. Electron microscopic examination of collateral cortical biopsy specimens showed swelling of perivascular astrocytic foot processes, but no endothelial abnormality. We feel that the uptake of radionuclide and dye-albumin complex by the perivascular astrocytes represents enhanced transendothelial transport rather than passage of molecules between endothelial cells. The significance of this presumably transient phenomenon is discussed.

ISSN:0039-2499    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

The canine middle cerebral artery (MCA) was embollzed with a pliable cylinder 8 mm long by 1.6 mm in diameter via the internal carotid artery. Both control and experimental embolectomies were performed 6 hours following embolization. The experimental animals were treated with low molecular weight dextran (LMD). In the control animals, the arerage volume of infarction in the brain was 1.45 cm.' In the experimental animals the average volume of infarction was 0.13 cm.3

ISSN:0039-2499    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

A 47-year-old patient had lesser development of her left limbs and face, smaller left rascular structures, and severe occlusive disease of the left internal carotid, left subdavian, left vertebral and left iliac arteries. In 12 examples of occlusion of a carotid artery, 10/11 with unequal vascular luminal size had the occlusion on the smaller side. Of 20 patients with severe asymmetrical carotid stenosis, 13/17 with unequal size had more stenosis on the smaller side. These preliminary observations suggest that a small vessel may be more likely to occlude than its larger counterpart

ISSN:0039-2499    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

Duplex scanning prorides real time B-raode images of the carotid bifurcation Teasels along with a single gate pulsed Doppler flow Telocity detector. By using the B-mode output of the duplex system to measure the Doppler angle and spectrum analysis to measure the frequency content of the Doppler signal, instantaneous flow Telocity can be calculated.Mean velocity at peak systole was calculated retrospecthely in 68 common (CCA) and internal (ICA) carotid arteries of 39 patients who had undergone prlor angiography and prospecthely in 30 arteries of 15 healthy young controls. The ratio of mean peak ICA Telocity to mean peak CCA Telocity at systole (VlCA/VCCA) was below 0.8 in all 36 normal arteries and above 1.5 in all 21 high-grade stenoses of 60% or greater diameter reduction. Sixty-one percent of 41 Tessels with less than 10 to 55% diameter redaction had a velocity ratio between 0.8 and 1.5. Only 10% of all ICA's with any stenotic lesion were incorrectly classified as normal. VlCA/VCCA appears to be an accurate Indicator of the degree of ICA stenosis.

ISSN:0039-2499    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

Male and female, spontaneously hypertensive rats (SHR) with blood pressures ranging from 190–210 mmHg were subjected to unilateral or bilateral carotid artery Ugation. Representative numbers of animals were killed 2, 4, 6, 8, 10, 12, 24 and 48 hours later. Severe cerebral ischemia caused a significant and protracted increase in the pre-exlstent high blood pressure, the enzymes CPK, SGOT and LDH triglycerides, free fatty acids, glucose, and corticosterone. Despite these marked pathophysiologic changes, the brains of these animals were free of real damage except for cerebral edema and scattered petechiae. Some of the animals developed massive atrial thrombi and myocardial infarcts. It is suggested that severe cerebral ischemia precipitated the myocardial infarcts through the aegis of the hypothalamic-pituitary-adrenal stress response.

ISSN:0039-2499    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

Focal ischemia was produced in cat brain by occluding the middle cerebral artery. After 60 min of ischemia the rate of glucose utilization, as measured by the uptake of [14C] deoxyglucose ([14C]DG), was correlated with tissue levels of ATP, phospfaocreatlne, and lactate measured in the same regional samples. Ischemia caused local increases of [14C] DG uptake which were associated with mild to moderate anaerobic perturbations of metabolite levels. Altered metabolite levels also occurred in regions in which the rate of glucose consumption was not markedly different from (hat of the noo-ischemic hemisphere. In addition, there were regions with decreased [14C] DG uptake which invariably were depleted of ATP and phospbocreatine. Thus, suppression of glucose metabolism was restricted to the most severely iscbemJc areas, where the delivery of glucose may be rate-limiting.

ISSN:0039-2499    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

In 18 autopsies from patients with primary pontine hemorrhage we studied the sites of bleeding, the volumes and development of hematomas and clinicopathological correlations. A modular optical electronic planimeter was introduced to measure the size of hematomas. The series of patients can be divided into 2 groups from the viewpoint of bleeding sites, their development and clinical symptomatology. These are 1) the tegmentobasiiar type and 2) the tegmentai type. The precise location of the orgin of hemorrhage, and the approximate volume of hematomas can now be determined with the help of computerized tomography. This information will be of help in understanding clinical symptoms. Two different typical patient reports, selected from the collection, are presented.

ISSN:0039-2499    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

Symptoms of cerebral ischemia following superficial temporal artery (STA) to middle cerebral artery (MCA) anastomosis are uncommon and are usually related to impaired flow through the anastomosis or occlusion of the cortical receptor artery. In this report, 3 patients are described who developed symptoms of cerebral ischemia after surgery despite a widely patent anastomosis. In each patient, postoperative angiograpby revealed occlusion of a previously demonstrated high-grade stenosis of the intracranial internal carotid artery (ICA) or MCA. Occlusion of the stenotic artery was probably related to decreased velocity of blood flow through the narrowed vessel resulting from alterations in flow patterns following anastomosis.

ISSN:0039-2499    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

The authors report a young woman with bilateral internal carotid artery occlusion shown by carotid angiography. There was spontaneous bilateral recanalization demonstrated radiographically. The possible causes, e.g. the intake of oral contraceptire drugs, a spontaneous intimal dissection and other etiological features are discussed and the literature is reriewed.

ISSN:0039-2499    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

The external diameters of rat and rabbit basilar arteries were determined before and after formaldehyde fixation in relaxed and drug constricted vessels. Fixation usually resulted in an immediate vessel constriction followed by partial relaxation after several hours. However, the results were inconstant from vessel to vessel and from area to area of the same vessel. It is concluded that morphologic as well as morphoihetric assessment of formaldehyde-fixed basilar arteries is unreliable.

ISSN:0039-2499    

出版商:OVID    

年代:1980

数据来源: OVID