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991.
J. C. Merrick B. T. Edelson V. Bhardwaj P. E. Swanson E. R. Unanue 《The American journal of pathology》1997,151(3):785-792
During the acute phase of growth of Listeria monocytogenes in spleen and lymph nodes, the infective foci consist of macrophages and neutrophils accompanied by extensive death of lymphocytes. Many of the lymphocytes die by apoptosis. The lesions are found by 48 hours after infection and can regress with time. Depending on the dose, the infected foci can be restricted to the thymus-dependent areas or can occupy the entire lymphoid tissue. The Listeria in the lesions are primarily found inside macrophages, but a few are extracellular amid cellular debris. Lymphocyte death appears to be an obligatory step in primary Listeria infection, the extent of which is controlled by the early restriction of Listeria growth by the innate cellular system. 相似文献
992.
George Lee Morris W. M. Mueller F. Z. Yetkin V. M. Haughton T. A. Hammeke S. Swanson S. M. Rao A. Jesmanowicz L. D. Estkowski P. A. Bandettini E. C. Wong J. S. Hyde 《Epilepsia》1994,35(6):1194-1198
Summary: Functional magnetic resonance imaging (FMRI) detects signal changes in brain that accompany regional changes in neuronal activity. In normal human brain, FMRI shows changes in signal in the postcentral gyrus or superior temporal gyrus that correlate with voluntary motor activity or language processing, respectively. The model used to explain the changes in signal linked temporally with cerebral activity is a reduction in cerebral capillary deoxyhemoglobin concentration due to the increased blood flow that accompanies neuronal activity in the cerebrum. FMRI has been used in normal subjects but not extensively in patients. To determine the feasibility of using FMRI to map cerebral functions in patients with partial epilepsy syndromes, we performed a pilot study, using FMRI to identify signal changes in motor and language areas in response to tasks that activate those areas. Signal changes in epilepsy patients approximated those observed in volunteers. We conclude that FMRI can be developed as a method for functional cerebral mapping in partial epilepsies. 相似文献
993.
D O Wiebers J W Swanson T L Cascino J P Whisnant 《Stroke; a journal of cerebral circulation》1989,20(4):554-558
We describe four patients with episodic bilateral vision impairment related exclusively to light exposure. Each had angiographically documented bilateral high-grade stenosis or occlusion of the internal carotid arteries. This phenomenon appears to be related to bilateral simultaneous retinal ischemia delaying regeneration of visual pigments in the pigment epithelial layer. It must be distinguished from bilateral occipital lobe ischemia caused by vertebrobasilar system disease. 相似文献
994.
995.
996.
Pacidamycins, a novel series of antibiotics with anti-Pseudomonas aeruginosa activity. III. Microbiologic profile 总被引:1,自引:0,他引:1
P B Fernandes R N Swanson D J Hardy C W Hanson L Coen R R Rasmussen R H Chen 《The Journal of antibiotics》1989,42(4):521-526
Pacidamycins are nucleosidyl-peptide antibiotics which have activity only against Pseudomonas aeruginosa. Their MICs for other organisms such as Enterobacteriaceae, Staphylococcus aureus, most Streptococci and other Pseudomonas species are greater than 100 micrograms/ml. These compounds had no activity against erythromycin-susceptible Streptococci. The MICs for Streptococcus pyogenes with constitutive- and inducible-type of macrolide-lincosamide-streptogramin resistance were 12.5 and 25 micrograms/ml, respectively. The MICs against P. aeruginosa ranged from 8 to 64 micrograms/ml. The activity of these compounds was 1 to 2-fold less in serum than broth. Time-kill curves were performed using 4 and 8 times the MIC of pacidamycin 1. It was bactericidal against P. aeruginosa (3 log10 decrease in 4 to 6 hours). At 24 hours, resistant mutants were found in the cultures. The MICs of piperacillin and gentamicin for these mutants were the same as for the parent strain. The frequency of resistance to these compounds was less than 3.5 x 10(-6). The resistant mutants were stable after 10 transfers in antibiotic-free medium. The pacidamycins were inactive against P. aeruginosa in mouse protection test. After a single subcutaneous injection of 25 mg/kg of pacidamycin 1, the Cmax was approximately 50 micrograms/ml and the serum half-life was 0.5 hour. 相似文献
997.
Malignant tumors of the oral cavity make up approximately 4% of all cancers occurring in men and 2% in women. In spite of this relatively small incidence, the functional and cosmetic disabilities resulting from this disease produce a profound impact on those stricken. Although the oral cavity is one of the most accessible areas to inspection and palpation, most patients developing oral cavity cancer present with advanced disease. Regional metastases are present in approximately 30% of these patients. A number of therapeutic modalities are available for management of cancer of the oral cavity. The most important include surgical excision, radiation therapy, chemotherapy, or a combination of two or more of these modalities. Surgery and radiotherapy are equally successful in controlling smaller tumors, but advanced tumors are best treated with a combination of surgery and irradiation with or without the addition of chemotherapy. Although combined therapy continues to become more common, it has had little impact on survival rates. Most patients dying of oral cavity cancer die of local regional disease. It is this group of patients that will benefit from newer surgical approaches that can provide an opportunity to increase control of local disease. We believe that an interdisciplinary approach combining the skills of the head and neck oncologic surgeon and the Mohs surgeon may provide a more effective method of controlling oral cancer, while at the same time lessening the functional and cosmetic deformities that frequently result following surgical treatment of this disease. Complete microscopic analysis of all surgical margins (as opposed to random analysis of isolated margins) theoretically should ensure better local control of cancers involving the oral cavity. 相似文献
998.
Lisa J. Herrinton Paul A. Demers Thomas D. Koepsell Noel S. Weiss Janet R. Daling John W. Taylor Joseph L. Lyon G. Marie Swanson Raymond S. Greenberg 《Cancer causes & control : CCC》1993,4(2):83-92
The purpose of this population-based case-control study was to learn whether risk factors differ for the individual immunoglobulin types of multiple myeloma. In particular, we sought to determine whether IgA and IgG myeloma were related to a history of exposure to reported IgA- and IgG-stimulating conditions, respectively, or to a history of selected occupational and physicochemical exposures. The M-component immunoglobulin type was determined from immunoelectrophoresis as reported in medical records, and exposure status was obtained through in-person interviews. IgG (56 percent) and IgA (22 percent) M-components predominated. For 17 percent of cases, no peak was found on immunoelectrophoresis; they were presumed to have light-chain myeloma. Persons with these three types of myeloma did not differ with respect to distributions of age or race, but a somewhat higher proportion of light-chain cases were women (58 percent cf 45 percent of all other cases). Detailed analysis of the IgA and IgG subtypes provided little evidence that they differ with respect to prior immune stimulation or employment in several specific jobs. IgA myeloma, but not IgG myeloma, was associated modestly with a history of exposure to chest and dental X-rays. Our study provides little evidence that IgA and IgG myeloma differ with respect to the risk factors examined.Ms Herrinton and Drs Koepsell, Weiss, and Daling are with the Department of Epidemiology, University of Washington, Seattle, WA, USA, and the Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA, USA. Dr Demers is with the Department of Environmental Health, University of Washington, Seattle, WA, USA. Dr Taylor is with Group Health Cooperative of Puget Sound, Seattle, WA, USA. Dr Lyon is with the School of Medicine, University of Utah, Salt Lake City, UT, USA. Dr Swanson is with the Cancer Center, Michigan State University, East Lansing, MI, USA. Dr Greenberg is with the School of Public Health, Emory University, Atlanta, GA, USA. Address correspondence to Ms Lisa Herrinton, Fred Hutchinson Cancer Research Center, 1124 Columbia MP-381, Seattle, WA 98104, USA. The project was supported by grants CA23350, CA39779, and CA09168 from the US National Cancer Institute. 相似文献
999.
1000.
IgE and IgG antibodies to beta-propiolactone and human serum albumin associated with urticarial reactions to rabies vaccine 总被引:2,自引:0,他引:2
M C Swanson E Rosanoff M Gurwith M Deitch P Schnurrenberger C E Reed 《The Journal of infectious diseases》1987,155(5):909-913
We examined the antibody response to a rabies vaccine doubly inactivated with 0.025% beta-propiolactone and 0.1% tri(n)butyl phosphate and stabilized with 2.5% human serum albumin. Antibodies were measured by using the following four antigen preparations: complete doubly inactivated rabies vaccine, rabies vaccine inactivated only with tri(n)butyl phosphate, beta-propiolactone and human serum albumin, and human serum albumin alone. The fluid phase of the preparation of beta-propiolactone and human serum albumin completely inhibited IgE binding to solid-phase vaccine. Of 21 subjects with urticarial reactions to a booster, 19 had IgE to doubly inactivated vaccine and to beta-propiolactone and human serum albumin. None of 27 immunized subjects without urticaria had detectable IgE. In paired pre- and postimmunization sera, IgE appeared in six of seven of the subjects with urticaria and in one of seven nonreactors. These sera did not contain a significant level of IgE to singly inactivated vaccine or to human serum albumin alone. 相似文献