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71.
P-fimbriae vaccines   总被引:3,自引:0,他引:3  
To test for cross-protective capacity of two different P-fimbriae vaccines we vaccinated baboons with fimbriae purified from either Escherichia coli strain ER2 or strain JR1. The vaccinated animals showed elevated antibody titers to P-fimbriae from each of the E. coli strains used, suggesting cross-reactivity as was expected from the results of immunoprecipitation of the fimbriae. Enzyme-linked immunosorbent assay inhibition by heterologous P-fimbriae proved this to be true immunologic cross-reactivity.  相似文献   
72.
Treatment of juvenile patients with a missing maxillary incisor is difficult, because an implant cannot be placed until growth is completed. The other minimally invasive alternatives are also problematic: Removable dentures are rarely accepted by juvenile patients, and the conventional resin-bonded fixed partial denture often provides a poor esthetic result because the metal retainer causes the abutment teeth to lose their natural translucency and to become grayish. Moreover, the alveolar ridge defect makes it easy to identify the prosthesis in the pontic area. The present case report describes the prosthetic treatment of a juvenile patient who had lost a maxillary incisor to trauma. To avoid the disadvantages of conventional therapies, subepithelial connective tissue was grafted to reshape the alveolar ridge. The space was closed with an all-ceramic resin-bonded fixed partial denture.  相似文献   
73.
The role of the basal ganglia in syntactic language processing was investigated with event-related brain potentials in fourteen neurologically impaired patients. Seven of these patients had basal ganglia lesions while 7 other patients primarily had lesions of the left temporo-parietal region excluding the basal ganglia. All patients listened to sentences that were either correct or included a verb argument structure violation. In previous experiments this type of violation elicited a biphasic pattern of an N400-P600 complex in young healthy participants. While the N400 may result from incorrect semantic-thematic role assignment, the P600 reflects the fact that verb information does not license the syntactic structure at present. Results of the patient experiment revealed a double dissociation: patients with left temporo-parietal lesions only show a P600, whereas patients with lesions of the basal ganglia showed no P600, but a negativity with extended duration that resembled an N400. The latter pattern not only confirms previous reports that the basal ganglia modulate the P600 but extends these results by showing that the N400 as a late semantic-thematic integration process appears partially modulated by the basal ganglia.  相似文献   
74.
We report an unusual case of an enterovesical fistula secondary to adenocarcinoma of the appendix.  相似文献   
75.
Elevated concentrations of carbohydrate-deficient components of transferrin (CDT) in serum may be used as a sensitive and specific marker of regular, high alcohol consumption. When determined by a new, simplified assay, CDT values are nearly normally distributed in low- or non-alcohol-consuming control populations. The importance of transferrin phenotype for this normal variation was analyzed in 100 healthy, European men and women with no or negligible alcohol intake. No significant relation was found between phenotype and CDT value in this population. The three rare B-variants found had low CDT levels, and one subject, examined outside the study, with a rare D-variant indicated that D-variants may result in false-positive CDT values. Moreover, women tended to have somewhat higher values than men, in whom CDT levels were weakly correlated with age. Other as yet undefined biological factors are clearly responsible for the major part of the normal variation of CDT values in nonalcoholic individuals.  相似文献   
76.
OBJECTIVES: To develop an immune-competent animal model for mucosally derived squamous cell carcinoma (SCCA). STUDY DESIGN: Fifteen Fischer 344 rats were inoculated with 1, 2, 5, 10, or 20 x 10(6) FAT7 cells in their flanks. The animals were observed for tumor growth and metastasis. RESULTS: All animals developed tumors that grew exponentially. Pulmonary metastases developed in all animals and 13% developed lymph node metastases. CONCLUSION: The FAT7 flank tumor in Fischer 344 rats is a new animal model that closely resembles the behavior of human mucosal head and neck cancer. SIGNIFICANCE: The existence of an immune-competent, mucosally derived, and reliable animal model of SCCA that somewhat resembles human head and neck SCCA gives the opportunity to perform immune-modulating experiments on head and neck cancer in these animals. EBM rating: B-3.  相似文献   
77.
D Blum 《Neurology》1992,42(8):1642-1643
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78.
The clinical and economic effects of each of 3 alternatives—no prophylaxis, general prophylaxis, and selective treatment—have been assessed in conjunction with 3 types of surgery—general surgery, the subset surgery for cholelithiasis, and elective hip surgery. The costs of thromboembolic and hemorrhagic complications have been calculated from the figures for 28 patients hospitalized at the Department of Surgery, Malmö General Hospital, Malmö, Sweden. The anticipated number of thromboembolic complications—and thus even the number of fatal pulmonary embolisms—can be minimized in all 3 types of surgery by means of general prophylaxis. General prophylaxis with low-dose heparin is, however, accompanied by the greatest incidence of hemorrhagic complications. Health care costs are minimized with general prophylaxis in elective hip and general surgery, while no prophylaxis is the best alternative in surgery for cholelithiasis. From the patient's point of view, general prophylaxis minimizes the duration of thromboembolic disease in general surgery as well as in elective hip surgery. In surgery for cholelithiasis, however, no differences in health loss for the individual are shown between the 2 main alternatives, no prophylaxis and general prophylaxis. Selective treatment means treatment after diagnosis of thrombosis with some screening method. The alternative selective treatment was the least satisfactory of those 3 studied.
Resumen Los efectos clínicos y económicos de cada una de 3 alternatives en la profilaxis tromboembólica (no profilaxis, profilaxis general con heparina de baja dosis, y tratamiento selectivo) fueron valorados en 3 tipos de cirugía: cirugía general (abdominal), el subgrupo de cirugía general para colelitiasis, y cirugía electiva de cadera. Los costos de las complicaciones tromboembólicas y hemorrágicas fueron calculados a partir de las cifras observadas en 28 pacientes hospitalizados en el Departmento de Cirugía. El número de predicción de complicaciones tromboembólicas, y el número de embolismos pulmonares fatales pueden ser minimizados en los 3 tipos de cirugía mediante la profilaxis general. Sin embargo, la profilaxis general con heparina de baja dosis se acompaña de la más alta incidencia de complicaciones hemorrágicas.Los costos de la atención pueden ser minimizados mediante la profilaxis general en cirugía electiva de cadera y en cirugía general abdominal, en tanto que la no profilaxis es la mejor alternativa para la cirugía de colelitiasis.Desde el punto de vista del paciente, la profilaxis general minimiza la duración de la enfermedad tromboembólica en la cirugía general abdominal así como en la cirugía electiva de cadera. En la cirugía para colelitiasis, sin embargo, no se demuestran diferencias entre las dos alternatives principales, no profilaxis y profilaxis general.El tratamiento selectivo significa tratamiento una vez establecido el diagnóstico de trombosis mediante algún método de tamizaje. La alternativa de tratamiento selectivo fue la menos satisfactoria de las 3 alternatives estudiadas.

Résumé Les effets cliniques et financiers de 3 comportements variables: absence de prophylaxie, prophylaxie, traitement sélectif ont été évalué en fonction de trois types de chirurgie: chirurgie générale, chirurgie spéciale de la lithiase biliaire, chirurgie élective de la hanche. Les coûts des complications thrombo-emboliques et hémorragiques ont été calculés à partir des données numériques concernant 28 malades hospitalisés dans le service de chirurgie. Le nombre envisagé des complications thromboemboliques et par conséquent le nombre d'embolie pulmonaire fatale a été réduit dans les 3 types de chirurgie choisis grâce au traitement prophylactique. Cependant il convient de noter que le traitement prophylactique à l'aide de faible dose d'héparine s'accompagne de complications hémorragiques plus nombreuses.Les coûts des soins de la chirurgie élective de la hanche et de la chirurgie générale sont réduits grâce au traitement prophylactique alors que l'absence de traitement prophylactique représente la meilleure modalité à observer dans le traitement de la chirurgie biliaire.En ce qui concerne le point de vue du malade le traitement prophylactique réduit la durée de la maladie thromboembolique compliquant la chirurgie générale ou la chirurgie de la hanche. En revanche dans la chirurgie de la lithiase biliaire aucun inconvénient pour la santé du malade ne s'observe que le traitement prophylactique soit ou ne soit pas appliqué.Le traitement sélectif qui répond au traitement institué après que le diagnostic ait été posé par des méthodes de dépistage est la moins satisfaisante des trois attitudes envisagées.


Supported by grant no. 00759 from the Swedish Medical Research Council.  相似文献   
79.
The 11C-labelled benzodiazepine antagonist Ro 15–1788 (flumazenil) and positron emission tomography (PET) were used to determine quantitative characteristics of benzodiazepine receptor binding in the neocortex of healthy young men. Saturating doses of unlabelled flumazenil administered i.v., before or together with the ligand-reduced 11C-flumazenil accumulation in the neocortex by about 90 per cent. Saturating doses of unlabelled flumazenil had little effect on the accumulation of radioactivity in the benzodiazepine receptor-poor regions such as pons or white matter. By giving graded doses of unlabelled flumazenil together with the tracer, saturation isotherms were obtained allowing the calculation of receptor density (Bmax) and equilibrium dissociation constant (Kd) values on the basis of certain assumptions Bmax values were in the order of 90 pmol/g and Kd values in the order of 10 nM in the neocortex. Scatchard and Hill plots of the radioactivity data indicated that 11C-flumazenil binds to saturable sites of a homogeneous population. The data indicate that intravenous doses of 1 or 2 mg flumazenil result in a benzodiazepine receptor occupancy of about 50 per cent. The method described should be useful for studying regional differences in benzodiazepine receptor characteristics in the living human brain in healthy subjects and neuropsychiatric disorders, and also in relation to treatment with drugs interacting with benzodiazepine receptors.  相似文献   
80.
Volume expansion in the presence of elevated aldosterone availabilityis a hallmark of normal pregnancy. Intravascular volume depletioncharacterizes severe pregnancy-associated disease conditionssuch as intra-uterine growth retardation, chronic hypertensionor pre-eclampsia [1]. Two hypotheses have been forwarded toexplain volume depletion in pregnancy: the first hypothesischarges inappropriate sensing of vascular ‘overfilling’,resulting in an increased transendothelial loss of fluid tothe extravascular compartment. In contrast, the second hypothesisfocuses on vascular ‘underfilling’ due to inappropriatelylow aldosterone levels. The second hypothesis is based on theassumption that a compensatory increase in the circulating fluidvolume is required in normal pregnancy to support fetal substratedelivery. According to the second concept, maternal blood pressureincreases due to counter-regulatory mechanisms when placentalblood supply is reduced [2]. In support of the ‘underfilling’hypothesis are observations that a  相似文献   
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