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11.
A phenotypic female with mild mental retardation, minor facial anomalies, and short stature has been evaluated clinically and cytogenetically over 29 years. At age 59, she remains physically well and shows no signs of dementia. Cytogenetic analysis, performed on peripheral blood specimens on 10 occasions between 1961 and 1990, showed mosaicism with one cell line containing a large stable ring (15) chromosome and another cell line without the ring but with a 15qs +. The different cell lines remained constant. The case provides information on the natural history of the ring chromosome 15 syndrome.  相似文献   
12.
The first part of this study describes the distribution of all different types of octopaminergic, efferent dorsal unpaired median (DUM) neurons in the first two thoracic ganglia by immunocytochemistry, retrograde labeling, and intracellular staining. The prothoracic ganglion contains five different types of 10 DUM neurons. The mesothoracic ganglion has 21 octopaminergic somata in the DUM neuron cluster. Retrograde labeling and intracellular staining show that 19 of these 21 somata belong to five different types of efferent DUM neurons. In both ganglia, the number and the distribution of all types of DUM neurons are completely described. Differences in the distribution of efferent DUM neurons between the thoracic ganglia are discussed as functional segmental specializations. In the second part, we show that, in contrast to previous suggestions, DUM neurons are not recruited as a homogeneous population mediating general arousal but differentially, thus forming subpopulations of specific types. The existence or the absence of commonly occurring postsynaptic potentials in paired recordings clearly shows that only specific types of DUM neurons are targeted by the same presynaptic pathways. Within the thoracic ganglia, different subpopulations of DUM neurons can be distinguished by their different local inputs. Furthermore, only specific subpopulations of DUM neurons receive common intersegmental drive and inputs from the subesophageal ganglion. As a result of all our recordings, we propose a scheme for the differential activation of efferent DUM neurons. This scheme is sufficient to explain DUM neuron activity during principal motor programs.  相似文献   
13.
Soellner R 《Substance use & misuse》2005,40(9-10):1279-1293
In this paper the epidemiology of club drug use in Germany, including the use of 3,4-methylendioxy-N-methamphetamine (MDMA) known as 'ecstasy' and related substances such as speed, amphetamines, hallucinogens, and cannabis is described on the basis of five different surveys. Two of them are representative household surveys to monitor the licit and illicit drug use behavior of the German population. The third one is a longitudinal study aimed at exploring comorbidity and posited risk and protective factors in adolescents and young adults with specific emphasis on substance use-related disorders. Since ecstasy seemed to be associated with a new music culture of the '90s called "techno," two studies investigating the relationship of using ecstasy and related substances in the techno party scene are additionally presented. The question of the clinical impact of using ecstasy and related substances is raised in terms of substance use-related and mental disorders associated with the use of ecstasy. Finally, the motivation for using and stopping the use of ecstasy is addressed. It is shown that ecstasy has reached the second place (after cannabis) in illegal drug preferences of adolescents and young adults in Germany. Evidence is found that ecstasy use as well as ecstasy use-related disorders such as "abuse" and "dependence" are of a transient, "youth-limited" nature.  相似文献   
14.
Ohne ZusammenfassungMit 2 Textabbildungen.Herrn Prof. Dr. F. Alverdes und Herrn Prof. Dr. R. Bieling danke ich für die Anregung zu dieser Arbeit und für die stete Förderung bei ihrer Durchführung.  相似文献   
15.
Cancer burdens not only the patients themselves but also their personal environment. A few studies have already focused on the mental health and personal needs of caregivers of patients. The purpose of this retrospective analysis was to further assess the emotional burden and unmet needs for support of caregivers in a population of brain metastasis patients. In the time period 2013–2020, we identified 42 informal caregivers of their respective patients after palliative radiation treatment for brain metastases. The caregivers completed two standardized questionnaires about different treatment aspects, their emotional burden, and unmet needs for support. Involvement of psycho-oncology and palliative care was examined in a chart review. The majority of the caregivers (71.4%, n = 30) suffered from high emotional burden during cancer treatment of their relatives and showed unmet needs for emotional and psychosocial support, mostly referring to information needs and the involvement in the patient’s treatment decisions. Other unmet needs referred to handling personal needs and fears of dealing with the sick cancer patient in terms of practical care tasks and appropriate communication. Palliative care was involved in 30 cases and psycho-oncology in 12 cases. There is a high need for emotional and psychosocial support in informal caregivers of cancer patients. There might still be room for an improvement of psychosocial and psycho-oncological support. Care planning should cater to the emotional burden and unmet needs of informal caregivers as well. Further prospective studies in larger samples should be performed in order to confirm this analysis.  相似文献   
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We compared estimates for base excess of extracellular fluid (BE(ecf); mmol/L) obtained in five clinically used blood gas analyzers: AVL Compact 2 (Roche Diagnostics, Mannheim, Germany), Ciba-Corning 860 (Bayer Diagnostics, Fernwald, Germany), IL 1620 (Instrumentation Laboratories, Lexington, MA), Stat Profile Ultra (Nova Biomedical, Waltham, MA), and ABL 510 (Radiometer, Copenhagen, Denmark). A total of 134 measurements per analyzer were obtained in arterial and venous blood samples from 10 patients undergoing cardiac surgery and 65 measurements per analyzer in venous blood samples from 2 healthy volunteers. The blood samples were equilibrated in a tonometer with gases of known composition (37 degrees C). Additional theoretical studies were performed to evaluate the relationship between pH and calculated BE(ecf) value (with varied PCO(2)) using the formulas of the various analyzers. The standard deviations of repeated measurements were 0.24 mmol/L for ABL 510 and approximately 0.45 mmol/L for the other 4 analyzers. The maximal systematic difference between the average of all measurements of each analyzer was 3.7 mmol/L; this was primarily attributable to differences in measuring pH, and, to a lesser extent, to differences in calculation and determination of PCO(2). Comparison of the results from samples with different oxygen saturation showed that the relative alkalinity of deoxygenated hemoglobin (Haldane effect) can also influence the determinations of BE(ecf). IMPLICATIONS: A clinically useful way to quantify nonrespiratory disturbances of the acid-base balance is calculation of the base excess of extracellular fluid by using blood gas analyzers. In this study, we found significant variability in estimates of base excess of extracellular fluid obtained with five analyzers from different manufacturers. This variability is attributable to multiple factors, including lack of correction for deoxygenated hemoglobin (Haldane effect).  相似文献   
19.
Coordination of motoneuron activity is a fundamental prerequisite for the generation of functional locomotor patterns. We investigate the neural mechanisms that coordinate activity of motoneuron pools in the vertebrate spinal cord with differing phases of activity in the locomotor cycle in a simple motor system, the lamprey swimming network. In the region of dorsal fins the lamprey spinal cord contains two groups of motoneurons: the myotomal motoneurons that innervate the trunk muscles; and the fin motoneurons controlling muscle fibres of the dorsal fins. We investigated the activity of fin muscles during swimming in vivo and that of fin motoneurons during fictive swimming in vitro. During swimming in vivo with cycle periods of 4-8 Hz, fin muscle activity covered a broad portion of the cycle, with the peak of activity out-of-phase to the ipsilateral myotomal muscles. During fictive swimming evoked by N-methyl-d-aspartate in the isolated spinal cord, fin motoneurons expressed similar out-of-phase activity. The phase relationship of the synaptic drive to fin motoneurons was examined by recording their activity intracellular during fictive swimming. Three different forms of membrane potential oscillation with different time courses in the locomotor cycle could be distinguished. Sagittal lesions of the spinal cord in the segment where fin motoneurons are recorded and up to one segment rostral and caudal from it did not influence the out-of-phase activity pattern of the motoneurons. Our results indicate that coordination of fin motoneuron activity with the locomotor activity of myotomal motoneurons does not depend on intrasegmental contralateral premotor elements.  相似文献   
20.
This article examined the causes underlying low utilization of mental health services by Vietnamese immigrants in Australia. Study 1 examined cases of Vietnamese patients who had attended an anxiety disorders clinic, while Study 2 surveyed Vietnamese people in the community on their knowledge and attitudes towards common mental problems. Results from Study 1 showed that Vietnamese patients had significantly higher attrition rates, and presented with a larger number of nonanxiety disorders than their Australian-born counterparts. Study 2 results indicated that many Vietnamese people did not differentiate clearly between the terms 'stress', 'anxiety' and 'depression'. Additionally, many participants felt that there was a generally negative cultural attitude towards people suffering from these problems and the mental health system itself. These outcomes suggest the importance of education for ethnic communities regarding available mental health facilities and treatments offered, as well as specific information on mental illness to help remove stigma.  相似文献   
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