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101.
Wilson's disease is a hereditary autosomal recessive disorder of copper metabolism. The corresponding gene locus has been localized on the long arm of chromosome 13. Three different clinical variants of the disease can be distinguished: hepato-cerebral, abdominal/hepatic, and central nervous type. The heterogeneity of symptoms can cause problems in differential diagnosis, especially when another concordant disorder can also explain the pathogenesis of symptoms. The case report of a young man who suffered from brainstem contusion demonstrates the possibilities of misinterpretation because presenting symptoms could be attributed either to traumatic brain injury followed by adjustment disorder or Wilson's disease. Clinical signs included leftsided hemiparesis, bilateral gaze direction nystagmus, marked dysarthria with consecutive pervasive mutism, choreo-athetoid movements, spasmodic torticollis and diplopia dependent on gaze direction. Slit lamp examination showed Kayser-Fleischer's corneal ring. EEG- and computer assisted tomography investigations revealed non-specific findings. The patient was treated with D-Penicillamine. Alternative treatment with oral zinc preparations is discussed.
Zusammenfassung Beim Morbus Wilson handelt es sich um eine autosomal rezessiv vererbte Störung des Kupferstoffwechsels. Der Genort konnte auf dem langen Arm des Chromosoms 13 lokalisiert werden. Klinisch können aufgrund ihrer Symptomatik drei Verlaufsformen (hepato-zerebraler, abdominalhepatischer und zerebraler Typ) unterschieden werden. Die Vielfalt der Symptome kann differentialdiagnostische Schwierigkeiten bereiten. Das Beispiel eines jungen Mannes mit einer traumatischen Hirnstammkontusion zeigt, wie die Diagnose der hepato-lentikulären Erkrankung dadurch erschwert wurde, daß die Pathogenese der Symptome durch die Hirnstammkontusion und darauf folgende Anpassungsstörungen erklärt worden war. Die Symptomatik bestand aus linksseitiger Hemiparese, lateralem Blickrichtungsnystagmus, Dysarthrie mit nachfolgendem universalem Mutismus, choreo-athetodischen Bewegungsstörungen, Torticollis spasmoidicus und blickrichtungsabhängigem Auftreten von Doppelbildern. Bei der Spaltlampenuntersuchung stellte sich der Kayser-Fleischer Ring dar. EEG- und computertomographische Untersuchungen erbrachten nur unspezifische Befunde. Die Behandlung erfolgte mit D-Penicillamin. Die alternative Behandlung mit oraler Gabe von Zinksalzen wird diskutiert.

Résumé La maladie de Wilson est une affection héréditaire autosomale recessive concernant le métabolisme cuivré. Le locus du gène a été situé sur le bras long du chromosome 13. Du point de vue clinique on distingue trois formes symptomatologiques: le type hepato-cérébral, hepato-abdominal et cérébral. La diversité des signes cliniques peut poser des problèmes de diagnostic différentiel, car d'autres affections peuvent se présenter avec cette même Symptomatologie. Nous rapportons ici l'exemple d'un homme jeune, porteur d'une maladie de Wilson et victime d'une contusion traumatique du tronc cérébral, dont les signes cliniques ainsi que les troubles du comportement pouvaient été autant rapportés à la contusion du tronc cérébral qu'à l'affection métabolique.La Symptomatologie comprenait une hemiparesie gauche, un nystagmus lateralisé, une dysarthrie avec mutisme secondaire universel, des mouvements choréo-athétosiques, un torticolis spasmodique et une diplopie dépendante de la direction du regard. L'examen à la lampe à fente permettait à mettre en evidence un anneau de Kayser Fleischer. L'EEG et le scanner cérébral ne montraient pas d'anomalies specifique.Le traitement a consisté en l'administration de D-Penicillamine. Traitment alternative avec les sels de zinc est discuté.
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102.
Summary: Bovine immunoglobulins are made from genes belonging to a small family of closely related Vh, genes. In this respect cattle resemble all species of domesticated mammals, which also use one VH family The family, named BoVH1, is homologous to the mouse Q52 family, and there are no more than 20 genes of this family in the bovine genome. Another feature of bovine heavy chains is the use of long CDR3s, which have an average of 21 codons. It seems that there are several families of long, closely related D genes rich in glycine and tyrosine responsible for this length. Sequences described as targets for mutations in other species can be found in CDR1, CDR2, and the putative D genes. The mutation mechanism starts at some point between late fetal stage and birth and seems to be antigen Independent. Diversity seems to be generated by hypermutation, although other mechanistns cannot be discomited at this time. Contrary to humans and mice, which have several Vh gene families comprising more than 100 genes, cattle use only a few genes and long CDR3s followed by somatic mutation to generate the necessary diversity to recognize the universe of antigens they will encounter during their life.  相似文献   
103.
The development and implementation of effective community support systems are goals of many public mental health authorities who are attempting to shift the focus and dollars for mental health services from inpatient to community care. This article presents the results of a survey which asked 90 community mental health agency case managers to assess the community support and residential needs of over 1400 of their clients. Medication monitoring and therapy were rated high priority needs. Psychosocial treatment, day and vocational activities also ranked high. Survey responses regarding residential services indicated a need for more supported and supervised options.The study reported was a collaborative effort by county and agency staff.  相似文献   
104.
Comparative study of brain morphology in ants   总被引:1,自引:0,他引:1  
Brain morphology, with special attention to the three dimensional form of the corpora pedunculata, was studied in thirteen species of ants, representing four subfamilies of Formicidae. The results can be summarized as follows. (1) The neural systems processing optic and olfactory information differ in the evolutionary history among the studied taxa. A positive correlation can be demonstrated in the phylogenetic history of the corpora pedunculata, central body, cerebral bridge and olfactory lobe, but not the optic lobe. Ant species with very large eyes and thus, probably, highly developed vision, show gigantic optic lobes, with no exaggeration of any other brain structure. (2) More social species have more complex chemical communication systems and better developed corpora pedunculata (more surface in foldings of the calyces) and olfactory lobes; however, this tendency seems to reverse in highly social species with a sophisticated polymorphic caste system: individuals of these species are generally less developed neurally. (3) There are differences between the form of the internal and external calyces of the corpora pedunculata, and these differences are proportionately more pronounced in species with complex social organization. (4) Individuals from different worker castes of the same species differ in their brain morphology, but each species shows a different pattern of variation among their castes. (5) Brain structure shows characteristic marks due to the different phylogenetic developments in the taxa studied. For example the trends in brain volume-body size ratio are different for the various subfamilies, suggesting a divergent phylogenetic history.  相似文献   
105.
We investigated non-rapid eye movement (non-REM) sleep in patients with newly diagnosed Parkinson's disease (PD) who had never previously received dopaminergic medication. There were no significant differences in the conventional sleep parameters between de novo patients with PD and a healthy control group, but the length of stage 1 sleep and the number of awakenings increased significantly upon administration of dopaminergic drugs. Analyzing the quantitative electroencephalogram (EEG), we observed a significant reduction in the low-delta frequency range and a nonsignificant increase in the sigma frequency range in de novo patients with PD. The dopaminergic medication also nonsignificantly reduced the low-delta and sigma frequencies, the latter to the level of the controls. Possible mechanisms that may account for the observed differences are discussed. It is suggested that Parkinson's disease as well as the application of dopaminergic drugs exerts a desynchronizing effect on the sleep EEG that is reflected in a disruption of sleep continuity.  相似文献   
106.
An experimental drug, 1-(1,3-benzodioxol-5-ylcarbonyl)piperidine, that facilitates glutamatergic transmission in brain after systemic administration was tested for its effects on the induction of long-term potentiation in the hippocampus of rats. Intraperitoneal injections of the drug markedly increased the degree and duration of long-term potentiation; similar results were obtained with an analogue of 1-(1,3-benzodioxol-5-ylcarbonyl)piperidine that was also found to improve retention of memory in a radial maze task and in an odor-matching problem. These results define tools for enhancing long-term potentiation in vivo and confirm an important prediction from the hypothesis that long-term potentiation is a substrate of memory.  相似文献   
107.
We have investigated the ontogeny of MHC class I, class II, CD45, and macrophage antigens in wholemounts of normal human fetal retina at 10–25 weeks gestation (WG) using monoclonal antibodies and immunogold histochemistry. MHC class I antigens were expressed on retinal vascular endothelial cells and provided a useful marker of vessel organization from 14–25 WG. Microglial cells expressed immunoreactivity to MHC class I, class II, and CD45 antigens from 10 WG (pre-vascularization) and macrophage S22 (Mac S22) antigen from 14 WG (post-vascularization), although none of the antigens tested were detected on neuronal or macroglial elements. Microglia expressing MHC, CD45, and macrophage antigens occurred in both ramified and rounded forms with no close correlation being observed between morphology and antigenicity. The numbers of immunoreactive cells labeled with each of the four markers increased steadily throughout gestation in all specimens studied. Equivalent numbers of microglia expressed MHC class I, class II, and CD45 antigens in retinae at similar gestational ages; however, our data indicate that microglia expressing Mac S22 antigen comprise approximately 40% or less of the population of MHC and CD45-immunoreactive cells during development. Topographical analyses suggest that MHC class I, class II, and CD45-positive microglia enter the retina from both the peripheral retinal margin and the optic disc from at least 10 WG; Mac S22-positive cells appear in association with the development of the retinal vasculature and enter the retina via the optic disc after 14 WG. © 1995 Wiley-Liss, Inc.  相似文献   
108.
Although natural family planning (NFP) is a form of contraception without ostensible maternal risks (other than pregnancy), potential fetal risks could exist if aging gametes are involved in inadvertent fertilization. In the following report, we first review animal studies firmly establishing that aging sperm and aging oocytes (delayed fertilization) cause chromosomal abnormalities in mammals and other species. We next review human studies associating decreased coital frequency with trisomy and studies of NFP populations that generally show no increased frequency of anomalous offspring or spontaneous abortions. Our rationale for initiating an international cohort study is presented, along with the experimental design selected. Preliminary findings indicate that the experimental design chosen will indeed provide information allowing NFP safety to be assessed definitively.
Resumen Aunque la planificación familiar natural (PFN) es una forma de anticoncepción sin riesgos maternos ostensibles, (fuera del embarzo) podrían existir posibles riesgos fetales di gametos que están envejeciendo son inadvertidamente fertilizados. La primera revisión de estudios en animales establece firmemente que espermatozoides y oocytos en envejecimiento (fertilización tardía), causan anormalidades cromosómicas en mamíferos y otras especies. A continuación revisamos estudios en humanos que asocian la disminución de la frecuencia coital con trisomía, y estudios de poblaciones practicando PFN que generalmente no muestran aumento en la frecuencia de descendientes anormales o de abortos espontáneos. Presentamos nuestras razones para iniciar el estudio de una cohorte internactional ademas del diseño experimental elegido proveerá información alegando que la inocuidad de la PFN sea definitivamente valorada.

Resumé Bien que le planning familial naturel (PFN-NFP) soit une forme de contraception ne présentant pas de risques manifestes pour la mère (autres qu'une grossesse), il pourrait y avoir des risques potentiels pour le foetus si des gamètes âgés sont par inadvertance fécondés. Nous passons en revue tout d'abord des études effectuées sur des animaux, établissant fermement que le sperme veillissant et les oocytes vieillissants (fécondation retardée) provoquent des anomalies chromosomales chez les mammifères et d'autres espèces. Nous examinons ensuite des études sur des humains, qui associent diminution coitale et trisomie, et des études de populations pratiquant le PFN, qui ne révèlent généralement pas de fréquence accrue d'enfants anormaux ou d'avortements spontanés. Cette communication expose la raison pour laquelle nous avons entrepris une étude sur une cohorte internationale, ainsi que le concept d'expérimentation que nous avons choisi. Les constatations préliminaires indiquent que ce concept fournira véritablement des informations qui permettront d'évaluer de façon définitive la sécurité du PFN.
  相似文献   
109.
We studied the relationship between Osgood-Schlatter disease and torsional abnormalities of the lower limb in 21 boys with this condition and 20 age- and sex-matched controls. 3 groups of knees (20 control knees, 21 symptomatic and 21 asymptomatic or less symptomatic knees) were subjected to clinical, radiographic and CT evaluation. We found no statistically significant differences between patients and controls, as regards femoral anteversion, patellar congruence angle, patellar tilt angle and anterior tibial tuberosity-trochlear groove distance, but the condylomalleolar angle and tibial torsion angle were greater in patients. We found no differences between symptomatic and asymptomatic or less symptomatic knees in any of the parameters. All the symptomatic knees were on the side preferentially involved in jumping and sprinting. This increase in external tibial torsion may play a role as a predisposing mechanical factor in the onset of Osgood-Schlatter disease in male athletes.  相似文献   
110.
BACKGROUND: The isolated perfused canine kidney has been established as a valid model for conducting both renal physiology and transplantation research. This model is of particular importance for developing new strategies to improve graft function after renal transplantation. In the present study, a newly developed method using isolated haemoperfused porcine kidneys was adapted for use in canine kidneys. In contrast to haemoperfusion, synthetic perfusion media can be standardized and can prevent the initiation of blood-mediated reperfusion reactions. Thus, an additional aim was to determine whether blood could be replaced by synthetic cell-free perfusion solutions. METHODS: Canine kidneys (n = 30) were harvested from donors euthanized in veterinary practices for causes unrelated to the present study. The kidneys were isolated and perfused with autologous blood or cell-free synthetic electrolyte buffer (Tyrode solution). During perfusion, we monitored renal perfusate flow (RPF), glomerular filtration rate (GFR), electrolyte and glucose reabsorption, oxygen consumption and urine concentration. RESULTS: Changes in perfusion medium did not affect the RPF. In contrast, GFR, urine concentration and oxygen consumption were significantly higher, whereas fractional excretion of sodium and glucose were significantly lower in blood- than in Tyrode-perfused kidneys. CONCLUSIONS: This system offers a simple model for studying whole-organ functional alterations after acute renal ischaemia. Renal function indicators were below values reported during in vivo physiological conditions. These functions were better conserved when kidneys were perfused with autologous blood than with Tyrode.  相似文献   
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