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41.
We review our experience with brain abscesses presenting as primary brain tumor over a 5-year period (1983 to 1988). Four of 66 (6%) patients admitted with the diagnosis of primary brain tumor by computed tomographic scans were found at craniotomy to have brain abscesses. Periapical abscesses found after surgery were determined to be the cause of brain abscess in two of four patients. Our experience suggests that periapical abscess may be a more frequent cause of brain abscess than previously thought, and should be considered before surgery in patients with a suspected brain tumor. 相似文献
42.
Paired Epstein-Barr virus (EBV)-negative and EBV-converted Burkitt lymphoma lines: stimulatory capacity in allogeneic mixed lymphocyte cultures 总被引:3,自引:0,他引:3
J. Avila-Cario S. Torsteinsdottir B. Ehlin-Henriksson G. Lenoir G. Klein E. Klein M. G. Masucci 《International journal of cancer. Journal international du cancer》1987,40(5):691-697
Epstein-Barr virus (EBV)-negative Burkitt lymphoma lines (BLE-) and their in vitro EBV-converted sublines (BLEc), obtained by infection with the P3HRI and B95-8 strains of EBV, were compared for their capacity to induce T-lymphocyte proliferation in allogeneic mixed lymphocyte cultures (MLC). Regardless of the virus strain used for conversion, the BLEc lines induced a considerably stronger primary MLC response than their EBV-negative parentals. Only the BLEc lines were able to maintain T-lymphocyte proliferation in repeated stimulations. The low proliferative response observed in cultures stimulated with BLE- cells was not due to the generation of suppressor cells or to the release of inhibitory factors. The increased stimulatory capacity of BLEc lines was unrelated to changes in expression of MHC class-I and class-II antigen, or of B-cell activation markers, and was not due to the reactivation of EBV-specific memory T cells, since lymphocytes from EBV-seropositive and seronegative donors responded similarly. The results indicate that the capacity of BL cells to elicit cellular immune responses may be influenced by their EBV-carrying status. 相似文献
43.
T A Klein D G Young S R Telford R Kimsey 《Journal of the American Mosquito Control Association》1987,3(2):154-164
Lutzomyia vexator is an efficient experimental vector of Plasmodium mexicanum, infecting 69.2% (9/13) of the Sceloporus undulatus lizards with as few as one bite. Sporozoites were present in the salivary glands by day 6.5 postfeed and infective by day 8 postfeed at 27 degrees C. The prepatent period was relatively long, ranging from 23 to 40 days for bite-induced infections and appears to be related to the number of sporozoites injected. The acute phase of the infection is initially exponential and rapid. All lizards (6) that were not sacrificed, died of fulminating infections from 13 to 56 days after parasites were seen in the blood films. Gametocytes from 2 experimentally infected lizards were infective to L. vexator during the course of the acute infection. The majority of P. mexicanum parasites were in erythrocytes of Sc. undulatus. Exoerythrocytic forms were observed in circulating lymphocytes and thrombocytes, lymphocytes of spleen and bone marrow, and endothelial cells of brain capillaries. 相似文献
44.
A J Klein 《Ear and hearing》1989,10(1):50-57
Hearing aids with signal processors use advanced circuitry to enhance speech recognition in noise. The effectiveness of these processors has not been well established. The purpose of this study was to evaluate performance on a speech recognition in noise task for listeners wearing a Zeta signal processor aid with the processor turned on and with the processor turned off. In addition, comparisons were made to performance while unaided and aided with a conventional hearing aid. A simple adaptive procedure and a psychometric function were the procedures used. Results for normal-hearing subjects indicate performance was usually better without a hearing aid. Performance when aided was similar for the processor on and the conventional aid. Performance in both of these conditions was clearly better than with the signal processor off. Although results for the hearing-impaired subjects varied widely, there was a trend for better performance with the conventional aid and with the signal processor on than for the signal processor off condition. 相似文献
45.
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48.
P J Sulak G S Letterie C C Hayslip C C Coddington T A Klein 《Fertility and sterility》1987,48(3):493-494
In two patients with apparent PTO, as diagnosed by HSG and laparoscopy, tubal patency was restored by hysteroscopic cannulation of the tubal ostia, followed by direct lavage. Tubal resection and reanastomosis/reimplantation may not be necessary for all patients with apparent PTO. 相似文献
49.
Inversion lateral ankle trauma: differential diagnosis, review of the literature, and prospective study 总被引:1,自引:0,他引:1
M Perlman D Leveille J DeLeonibus R Hartman J Klein R Handelman E Schulz S Wertheimer 《The Journal of foot surgery》1987,26(2):95-135
This study is comprised of 71 patients with inversion injuries. The purpose of this article is to present a logical and orderly approach in evaluating these injuries. A comprehensive review of the literature concerning diagnostic techniques and mechanisms of injury related to inversion ankle trauma is presented. Inversion ankle injuries are frequently misdiagnosed as simple sprains when frequently there are other pathologies present. The standard approach of evaluating inversion ankle injuries is often inadequate. 相似文献
50.
78 geriatric patients predominantly suffering from cardiocerebrovascular diseases (stroke, heart insufficiency) and lesions respectively operations of the locomotion system (fractures, arthroses) were admitted in 1987 from acute hospitals for after-treatment (short-term care). 35 (= 45%) of them (average age 80 (61-92) could be discharged after 63.5 days on average, 11 died from intercurrent complications, 9 remained for long-term care as inrehabilitable. Besides other concomiting troubles mainly cardiac and circulation affections were present in the majority of patients. Their identification (a. o. by means of ultrasonic methods) and therapy also means a secondary prevention of cerebral as well as of fall and injuries inducing risk factors. The results confirm the principal rehabilitation chance of multimorbid geriatric patients by use of the diagnostic and therapeutic special potential of geriatrics. 相似文献