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41.
Regional cerebral blood flow (CBF) was studied tomographically with 133Xe administered by inhalation over a 1-min period at a concentration of 10 mCi/l. A fast rotating (dynamic) single-photon emission computed tomograph with four detector heads was used, an instrument that has been found to be well suited for detecting focal ischemia. In the present study its ability to detect focal hyperemia was investigated in 13 normal subjects studied during rest and during visual stimulation. A flickering light seen with eyes open and closed, increased blood flow in the visual cortex by 35% and 22% respectively. Looking at different pictures displayed on a screen raised regional CBF by 26%. The most complex task, reading and copying a text, increased blood flow by 45%. Averaging the different tasks resulted in a mean regional CBF increase in the visual cortex of 35%. The result is comparable with that obtained by positron emission tomography. Both forms of isotope tomography offer unique possibilities for the study of brain function in health and disease, possibilities not matched by X-ray tomography. The low cost and ready availability of appropriate single-photon radionucleides (133Xe and 127Xe) are mentioned.Supported by the Danish Medical Research Council, the Danish Sclerose Association, and the Johann and Hanne Weimann Foundation.  相似文献   
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Book reviews     
Recent Advances in Avian Immunology Research. B. S. BHOGAL & G. KOCH (Eds), Progress in Clinical and Biological Research Volume 307, New York, Alan R. Liss, Inc., 1989. 238 pp. US$59–50. ISBN 0–8451–5157–6.

Mechanisms of Disease. A Textbook of Comparative General Pathology. D. O. SLAUSON & B. J. COOPER, Baltimore, Williams & Wilkins 2nd Ed., 1990. 541 pp., £43.50. ISBN 0–683–07743–0.

Poultry Diseases. F. T. W. JORDAN (Ed), London, Bailliere Tindall, 3rd Edition, 1990. 464 pp., £19.90. ISBN 0–7020–1339–0.  相似文献   

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1350 embryos obtained by In Vitro Fertilization (IVF) have been examined with the reverse microscope before their transfer in utero. Some embryos are "morphologically normal" (34.7%); some others are atypical. It is difficult to determinate the implantation rate by embryo according to morphological aspect because, most of the time we transfer several embryos to only one patient and we do not know, in case of pregnancy, which one or which ones have developed. Nevertheless, we have tried to appreciate, for 500 embryos transfers after IVF, the incidence of morphological aspect according to the presence or absence of "morphologically normal" embryos. The implantation rate is significantly higher in the groups in which you find "morphological normal" embryos than in the group where they are missing. (19.7% and 19.2% vs 10.2%). It seems that the aspect of the embryo when it is transferred, has an incidence on its future development.  相似文献   
44.
Of the many cases of traumatic rupture of the aorta diagnosed each year at l"H?pital du Sacré-Coeur, Montreal, most patients are already in irreversible shock when seen. However, during the period Oct. 1, 1974 to Sept. 30, 1975, prompt surgical treatment saved six patients. One of these six patients had a complete trans-section of the aortic arch between the left carotid and left subclavian arteries with avulsion and slight retraction of the left subclavian artery. Repair of the aortic arch and left subclavian artery was accomplished without extracorporeal circulation. A sutureless temporary bypass shunt was created by (a) cannulating the ascending and descending aorta, the cannulas being secured with purse-string sutures and joined by a 3/8-inch (94-mm) polyvinyl chloride (PVC) tube connected to a "double T" adapter, and (b) joining two small PVC tubes from the adapter with two straight cannulas, a no. 14 being inserted into the innominate artery and a no. 12 being inserted into the left carotid artery. With this temporary bypass created, the ascending and descending aorta and aortic arch vessels were all clamped. Aortic continuity was re-established with a tubular Dacron graft (diameter, 19 mm) to which was anastomosed a side-arm of knitted Dacron (diameter, 10 mm) to repair the left subclavian artery. Throughout the temporary perfusion the brain, spinal cord and all abdominal viscera were well protected. No sign of ventricular distension was detected. This report is the first in which complete transsection of the aortic arch has been managed by a sutureless bypass shunt allowing perfusion of all aortic arch vessels without extracorporeal circulation.  相似文献   
45.
PURPOSE: To investigate the safety and tolerability and to explore the pharmacokinetic and pharmacodynamic profile of the humanized antiepidermal growth factor receptor monoclonal antibody EMD72000 in patients with solid tumors that express epidermal growth factor receptor (EGFR). PATIENTS AND METHODS: This was a phase I dose-escalation trial of EMD72000 in patients with advanced, EGFR-positive, solid malignancies that were not amenable to any established chemotherapy or radiotherapy treatment. EMD72000 was administered weekly without routine premedication until disease progression or unacceptable toxicity. RESULTS: Twenty-two patients were treated with EMD72000 at five different dose levels (400 to 2,000 mg/wk). National Cancer Institute common toxicity criteria grade 3 headache and fever occurring after the first infusion were dose limiting at 2,000 mg/wk; thus, the maximum-tolerated dose was 1,600 mg/wk. No other severe side effects, especially no allergic reactions or diarrhea, were observed. Acneiform skin reaction was the most common toxicity, but it was mild, with grade 1 in 11 patients (50%) and grade 2 in three patients (14%). Pharmacokinetic analyses demonstrated a predictable pharmacokinetic profile for EMD72000. Pharmacodynamic studies on serial skin biopsies revealed that EMD72000 effectively abrogated EGFR-mediated cell signaling (eg, reduced phosphorylation of EGFR and mitogen-activated protein kinase), with no alteration in total EGFR protein. Objective responses (23%; 95% CI, 8% to 45%) and disease stabilization (27%; 95% CI, 11% to 50%) were achieved at all dose levels, and responding patients received treatment for up to 18 months without cumulative toxicity. CONCLUSION: Treatment with EMD72000 was well tolerated and showed evidence of activity in heavily pretreated patients with EGFR-expressing tumors. EMD72000 at the investigated doses significantly inhibited downstream EGFR-dependent processes.  相似文献   
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In order to demonstrate the involvement of nitric oxide synthases (NOS) – in particular the inducible isoform (iNOS) – in inflammatory processes within the nasal airways, we used organ-bath incubation to study isolated inferior turbinates and mucosa of the maxillary sinus of guinea pigs. The pattern of the expression in various substructures of the nasal mucosa was of special interest. Mucosa was incubated for 6 h with lipopolysaccharides (LPS) produced by E. coli, interleukin II (IL-2) or tumor necrosis factor-alpha (TNF-α). Saline was used as the control solution. Following incubation the specimens were fixed in buffered 4% formaldehyde solution over a period of 4 h. Tissues were next exposed to nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase-reaction and immunostained with specific antibodies to iNOS. Results then showed a clearly increased or initiated expression of iNOS in epithelium, glands, leucocytes and blood vessels of treated tissues in comparison to the control specimens. The inflammatory mediator LPS and the cytokines Il-2 or TNF-α alone were found to be capable of increasing the expression of iNOS, although the effects of LPS clearly exceeded those of the cytokines. This finding implicates iNOS-generated nitric oxide as a key factor for causing nasal swelling, secretion and obstruction during nasal infections and allergic episodes. Received: 18 November 1997 / Accepted: 22 April 1998  相似文献   
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