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Antigens of Streptococcus sanguis   总被引:5,自引:25,他引:5       下载免费PDF全文
An antigenic analysis of the alpha-hemolytic streptococci isolated from dental plaque was performed by use of antisera against a strain of Streptococcus sanguis (M-5) which was isolated from dental plaque. Immunoelectrophoretic and Ouchterlony tests of Rantz and Randall extracts of 45 strains gave positive reactions with the M-5 antisera. These strains represented 60% of the strains tested. The number of antigens which could be identified in these extracts varied from one to five and were designated a to e. The a antigen was found in 36 of the strains tested, including reference strains of S. sanguis and the group H streptococci. The strains reacting with the M-5 antisera were divided into two majors types: type I consisted of 23 strains in which the a antigen was found alone or with one or more of the c, d, and e antigens; type II consisted of 13 strains in which both the a and b antigens were found with or without one or more of the c, d, and e antigens. The remaining strains contained, either singly or in combination, the b, c, d, and e antigens but not the a antigen. Biochemical tests of representatives of each serotype and reference strains indicated that strains reacting with M-5 antisera were S. sanguis. These findings suggest that S. sanguis strains share common physiological and serological properties.  相似文献   
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The projections from the medullary and spinal dorsal horns to the dorsolateral pons were investigated in the cat utilizing both the retrograde and anterograde transport of a wheat germ agglutinin-horseradish peroxidase complex and the retrograde transport of the fluorescent dyes Fast Blue and Nuclear Yellow. After injections of wheat germ agglutinin-horseradish peroxidase into the area surrounding the brachium conjunctivum, numerous neurons were labeled ipsilaterally near levels of the obex in the paratrigeminal nucleus. Such neurons were located in connected pockets of neuropil located within the spinal trigeminal tract and along its medial edge. Most of the neurons labeled in the dorsal horns after such injections were found in lamina I. Those found in the medullary dorsal horn were mostly ipsilateral to the injection while those in the spinal dorsal horn were found bilaterally. Some labeled neurons were also found in lamina V of both the medullary and spinal dorsal horns bilaterally. When the injection was centered in either the medial parabrachial nucleus or the Kolliker-Fuse nucleus, a greater number of neurons were labeled ipsilaterally in lamina V of the medullary dorsal horn. Since neurons in lamina I of the medullary dorsal horn also project to the medial thalamus, fluorescent dyes were used to determine if the same neuron might project to both targets. Fast Blue was first injected into either the peribrachial area or the medial thalamus. After an appropriate period, Nuclear Yellow was injected into that target not injected first with Fast Blue. The injection of Nuclear Yellow was always placed on the side of the brain opposite to the first injection. Both dyes were transported retrogradely and were found in neurons located in lamina I of the medullary dorsal horn. However, no double-labeled neurons were seen. In general those labeled after injections of the medial thalamus were more superficial than those labeled after injections of the dorsolateral pons. The anterograde transport of wheat germ agglutinin-horseradish peroxidase was used to determine the termination of the projections from neurons in the medulary dorsal horn and the cervical spinal cord to the peribrachial area. After injections into these areas a moderate to sparse labeling of the lateral parabrachial nucleus and the Kolliker-Fuse nucleus was seen. It was mostly ipsilateral in cases with injections of the medullary dorsal horn but was bilateral following injections into the cervical enlargement.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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Burton  Wendy  Sahota  Pinki  Twiddy  Maureen  Brown  Julia  Bryant  Maria 《Prevention science》2021,22(3):345-356
Prevention Science - Poor participant engagement threatens the potential impact and cost-effectiveness of public health programmes preventing meaningful evaluation and wider application. Although...  相似文献   
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Background/purposeAdolescents have poor outcomes following testicular torsion directly attributable to delay from onset of symptoms to presentation to hospital. The aim of this study was to investigate the barriers to urgent presentation in young men.MethodsSemistructured interviews were undertaken with young men (11–19 years), using a topic guide exploring issues surrounding testicular pain and health. Thematic analysis was undertaken using a framework approach.ResultsTwenty-seven adolescents were recruited, data saturation was reached at sixteen participants, and median age was 13.5 years (range 11–18). The process by which an adolescent gets to hospital with testicular pain is slow. They must recognize the problem and alert their parents, who then use a ‘watch and wait’ policy to assess need for medical review, often leaving it ‘a day’ or overnight. Adolescent males do not engage with healthcare services independently of their parents. Additional factors preventing early presentation include: absence of knowledge about testicular pathology from adolescents and their parents; concern from the young people about raising a false alarm and family concerns about burdening healthcare services.ConclusionsRecommendations include designing a testicular health education campaign for young men and educating parents regarding the medical conditions where a ‘watch and wait’ policy may be harmful to their child.Level of evidenceVI  相似文献   
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Why do the vast majority of those who suffer harm from drinking fail to obtain treatment? Based on a review of research literature and educational and treatment program materials, a model of nonparticipation in treatment is proposed whereby particular population groups are separated out according to whether or not they exhibit specified characteristics related to both harm from drinking and attitudes towards treatment. Eleven groups have been identified in the model, each of which has different reasons for failing to seek and/or obtain treatment. It is suggested that differing educational program messages should be sent to each group. While the model does not purport to be wholly inclusive of all nonparticipation, it offers a basis for addressing the variety of disparate groups that suffer harm from drinking but do not obtain treatment.  相似文献   
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The Toledo Hospital has initiated many innovative quality programs. One initiated with the dietary department involved turning its wholesaler into a partner to provide better-quality products, lower costs and better service. Specific requirements were established in each of these areas including guaranteed mark-ups, price caps and performance reports. The hospital and the wholesaler also do joint negotiating with product manufacturers. Through these and other strategies, the hospital has reduced purchase prices for food items by over 4%, drastically reduced administrative costs of procurement and lead time, increased inventory turns to over 80 and given the dietary department a single resource for "one stop shopping."  相似文献   
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