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51.
Medical genetic histories of 165 children with primary central nervous system (CNS) tumours and 4599 relatives of these probands were examined to identify birth defects or genetic disorders that may be associated with the aetiology of CNS tumours. Twelve primary malignancies were found in 329 (4%) of the parents of probands. Two of 99 half sibs but no full sibs had malignancies. Twenty-four percent of families had histories warranting consultation for an inherited disorder or birth defect. Single instances of malformations or genetic disorders were reported in 36 families and several disorders were reported in more than one family, including familial hypercholesterolaemia (4), olivopontocerebellar atrophy (2), and familial abdominal aortic aneurysm (2). Although recurring abnormalities were not identified in probands, it is possible that one or more of the birth defects or genetic disorders observed in probands or relatives may be associated with CNS tumourigenesis.  相似文献   
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Summary Varying host reaction of the house fly, Musca domestica L., to parasitism by the braconid Aphaereta pallipes (Say) was chiefly correlated with the diet of the host. Some evidence was found that implicated the strain of the host, the rearing temperatures, the ages of the parasitoid and the host, and the site of oviposition. Though development of A. pallipes embryos was inhibited before they became encapsulated with melanin within the host, the presence of the parasitoid and (or) the effect of its paralyzing toxin that was injected into the host just before oviposition prevented normal larval, pupal, or adult development of the six house fly strains tested. A considerable increase of parasitoid survival occurred when M. domestica larvae were reared on a chemically defined diet.
Zusammenfassung Musca domestica L. reagierte unterschiedlich auf die Parasitierung durch die Braconide Aphaereta pallipes (Say). Die verschiedenen Reaktionen waren im wesentlichen mit der Art der Wirtsnahrung korreliert. Daneben finden sich Hinweise, daß auch der Wirtsstamm, dessen Zuchttemperatur, das Alter von Parasit und Wirt und der Eiablageort des Parasiten die Reaktionen beeinflussen. Obgleich die Entwicklung von Parasitenembryonen bereits gehemmt war, ehe sie innerhalb des Wirtes von Melanin eingeschlossen wurden, so verhinderten doch die Parasiten-embryonen und/oder die Wirkung der vor der Eiablage abgegebenen Paralysierungstoxine die normale Entwicklung der Wirte aus sechs Fliegenstämmen. Eine beträchtliche Steigerung der Überlebensrate der Parasiten trat ein, wenn M. domestica-Larven in einem Gemisch chemisch genau definierter Nahrung gezogen wurden.


With 8 Figures in the Text

Formerly National Research Council Postdoctorate Fellow, Research Institute, Belleville, Ontario.  相似文献   
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Zusammenfassung Der Mechanismus der Cytoprotektion von Prostaglandin (PG) auf die Magenmucosa ist unbekannt. Anaesthesierte Kaninchen erhielten in der Gruppe (GR) I (n=8) im. Aspirin (ASA) (100 mg/kg als Bolus, 66 mg/kg/h kontinuierlich) in der GR 11 (n=10) NaCI und in der GR III (n=7) zusätzlich zum ASA, PGE I (0,1 g/kg/min) als Infusion über 120 min. Der Mucosa-Blutfluß (MBF) wurde mit radioaktiven Mikrosphären gemessen. In der GR I fiel der MBF nach 15 min um 72,3+3,8% (+ SEM) und nach 120 min um 73,1+3,8% (p 0,05 gegen % Änderung in GR II und III). Nach 120 min zeigte sich in der GR I 19,8 + 7,6% der Fundusmucosa hämorrhagisch, in der GR 11 6,1 +5,2% und in der GR 1112,0+ 1,4% (p 0,05 gegen GR II und III). Wir schließen, daß der cytoprotektive Effekt des PGE I auf einer Aufhebung der ASA bedingten Mucosaischämie beruht.  相似文献   
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Quality of Life Research - This study examined the clinical utility of post-traumatic stress disorder (PTSD), low resilience, poor sleep, and lifetime blast exposure as risk factors for predicting...  相似文献   
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Zusammenfassung Es wird ein kurzer Überblick über die bei achondrodysplastischen Zwergen vorkommenden Wirbelsäulenveränderungen gegeben. Die häufig neurologischen Ausfälle beruhen in der Regel auf einer Kompression des Rückenmarkes und/oder der Cauda equina in dem verengten Wirbelkanal.Beschreibung eines eigenen Falles, bei dem das Bild einer Pseudo-Claudicatio intermittens durch eine abnorme Elongation der Kaudafasern um etwa 8 cm verursacht war. Nach operativer Dekompression bildeten sich die Störungen und Beschwerden zurück.
Summary A short review is presented of the spinal column changes which occur in achondroplastic dwarfs. The chief neurological results are, as a rule, due to compression of the spinal cord and/or of the cauda equina in the narrowed spinal canal.A personal case is described in whom the picture of intermittentpseudo-claudication was caused by an abnormal elongation of about 8 cm of the cauda equina roots. After decompressive operation the symptoms and signs regressed.

Resumen El autor presenta un estudio de las modificaciones del raquis en los enanos acondroplásticos. Los signos neurológicos importantes están por lo general unidos a la compresión de la medula o de la cola de caballo en el canal espinal.En una observación personal la pseudoclaudicación intermitente estaba en relación con una elogación anormal, de 8 cms., de las raices de la cola de caballo. Después de una operación descompresiva los síntomas regresaron.

Résumé L'auteur présente une étude des modifications du rachis chez les nains achondroplastiques. Les signes neurologiques importants sont en règle liés à la compression de la moelle ou de la queue de cheval dans l'étroit canal spinal.Dans une observation personnelle, la pseudo claudication intermittente était liée à une élongation anormale de 8 cm des racines de la queue de cheval. Après une intervention décompressive les symptômes ont régressé.

Riassunto Gli AA. fanno una breve esposizione delle modificazioni delle colonna vertebrale che si riscontrano nel nanismo acondroplasico.Le frequenti alterazioni neurologiche sono determinate di regola da una compressione del midollo spinale e/o delle cauda equina nel canale vertebrale ristretto.Gli AA. descrivono un caso personale, nel quale il quadro di una pseudoclaudicatio intermittens era causato da un allungamento delle fibre delle cauda di circa 8 cm.In seguito a decompressione operatoria i disturbi ed i dolori scomparvero.
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Osteosarcomatosis   总被引:10,自引:0,他引:10  
A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized.  相似文献   
60.
Summary The presence, chromatographic properties and localization of neuropeptide Y was demonstrated in postmortem human brain areas of neurologically and neuropsychiatrically normative controls using immunocytochemistry and high performance liquid chromatography combined with radioimmunoassay. NPY-immunoreactivity was found in many regions of the prosencephalon. Numerous perikarya and fibers were present in the neocortex, basal ganglia and limbic-hypothalamic areas. A moderate number of neurons and fibers was observed in the basal forebrain, including the septal complex. A comparative immunohistochemical investigation in perfusion-fixed brains of the old-world ape Saguinus oedipus revealed an almost identical distribution of NPY-immunoreactivity with only minor differences. Colocalization experiments on 1–2 m thin consecutive paraffin sections revealed a large number of NPY neurons throughout the human neostriatum and amygdaloid complex that were also positive for somatostatin. Our findings indicate that detection of neuropeptides in fresh or fixed post-mortem human tissue by different immunochemical methods may actually reflect the in vivo conditions. In addition, the wide distribution of NPY throughout the human brain and its colocalization with other neurotransmitters suggests a physiological role as neuroactive substance, i.e. neuromodulator in the primate central nervous system.  相似文献   
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