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Zusammenfassung In allen den bisher untersuchten Fällen von Sticker-Sarkome des Hundes wurden die gleichen Chromosomenanomalien gefunden: 58–59 Chromosomen, darunter 13–17 metazentrische und 40–45 telozentrische. Ein beobachteter Tumor wies die doppelte Chromosomenzahl auf, auch die Zahl der metazentrischen Chromosomen machte etwa das Zweifache des bisher mitgeteilten Wertes aus. Dieser Chromosomensatz war auch in den Zellen von Transplantaten nachzuweisen. Es dürfte sich also um eine stabile polyploide Abart des Sticker-Sarkoms handeln.
A new chromosomal variant of the Sticker venereal sarcoma
Summary In all earlier investigations of the Sticker venereal sarcoma in dogs identical chromosomal aberrations were found; there were 58–59 chromosomes of which 13–17 were metacentrics and 40–45 telocentrics. In the tumour presented here the karyotype was similar to that recorded previously except that the chromosome number was doubled; thus all the characteristic chromosomes were present in duplicate. The same duplicate chromosomal set was preserved when the tumour was transplanted to other dogs. Thus the tumour may be regarded as a stable polyploid variant of the Sticker venereal sarcoma.
  相似文献   
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Lim MC  Shipston MJ  Antoni FA 《Endocrinology》2002,143(10):3796-3801
Diagnostic tests of hypothalamic-pituitary-adrenocortical function in psychiatric illness largely report the interaction of hypothalamic secretagogues with glucocorticoids at the pituitary level. This study investigated whether the efficiency of glucocorticoid inhibition is subject to modulation by intracellular processes that enhance cAMP accumulation and/or facilitate membrane depolarization. The secretion of ACTH induced by corticotropin-releasing factor (CRF; 0.1 nM) in primary cultures of rat anterior pituitary cells was markedly inhibited upon a 2-h exposure to 100 nM corticosterone. Arginine vasopressin (2 nM) enhanced the cAMP as well as the ACTH responses to CRF and reduced the efficiency of glucocorticoid inhibition of ACTH release. The action of arginine vasopressin was mimicked by rolipram, an inhibitor of cyclic nucleotide phosphodiesterase type 4. Application of the broad specificity K(+) channel blockers clofilium and astemizole produced minor or no significant enhancement of CRF-induced ACTH release, respectively, but opposed the inhibitory effect of corticosterone. Specific blockers of HERG, KCNQ, and Isk channels had no effect on ACTH release under any condition examined. In summary, these data reveal multiple sites of posttranslational modulation of adrenal corticosteroid action at the level of the pituitary gland, which appear important for the outcome of diagnostic tests of hypothalamic-pituitary- adrenocortical function.  相似文献   
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Objective

To determine the effects of a high-intensity exercise therapy using sensorimotor and visual stimuli on nondemented Parkinson disease (PD) patients’ clinical symptoms, mobility, and standing balance.

Design

Randomized clinical intervention, using a before-after trial design.

Setting

University hospital setting.

Participants

A total of 72 PD patients with Hoehn and Yahr stage of 2-3, of whom 64 were randomized, and 55 completed the study.

Intervention

PD patients were randomly assigned to a no physical intervention control (n=20 of 29 completed, 9 withdrew before baseline testing) or to a high-intensity agility program (15 sessions, 3 weeks, n=35 completed).

Main Outcome Measures

Primary outcome was the Movement Disorders Society-Unified Parkinson Disease Rating Scale (MDS-UPDRS) motor experiences of daily living (M-EDL). Secondary outcomes were Beck Depression score, Parkinson Disease Questionnaire-39 (PDQ-39), EuroQoL Five-Dimension (EQ5D) Questionnaire visual analog scale, Schwab and England Activities of Daily Living (SE ADL) Scale, timed Up and Go (TUG) test, and 12 measures of static posturography.

Results

The agility program improved MDS-UPDRS M-EDL by 38% compared with the 2% change in control (group by time interaction, P=.001). Only the intervention group improved in PDQ-39 (6.6 points), depression (18%), EQ5D visual analog scale score (15%), the SE ADL Scale score (15%), the TUG test (39%), and in 8 of 12 posturography measures by 42%-55% (all P<.001). The levodopa equivalent dosage did not change.

Conclusion

A high-intensity agility program improved nondemented, stage 2-3 PD patients’ clinical symptoms, mobility, and standing balance by functionally meaningful margins at short-term follow-up.  相似文献   
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In order to clarify the role of reactive oxygen species and lysosomal enzymes in the etiopathogenesis of varicose veins, the investigation of their activities in serum and peripheral neutrophils of 17 patients with primary varicose veins was done. The mean activities of acid phosphatase, beta-D-glucuronidase (BDG) and N-acetyl-beta-D-glucosaminidase were higher in serum of patients with varicose veins than in serum of normal subjects. However, the mean BDG activity was lower in the patients' neutrophils and the activities of elastase and myeloperoxidase were higher than in clinically healthy persons. No changes have been observed in the lysozyme activity. The neutrophils of patients with varicose veins had a greater ability to increase superoxide production after their stimulation with opsonized zymosan or phorbol myristate acetate than the neutrophils of normal subjects, while no differences were found in the total reduction of iodonitrotetrazolium (INT) incubated with these leukocytes. The results may represent another piece of evidence suggesting the activation and involvement of neutrophils in pathogenesis of chronic venous insufficiency of lower limbs.  相似文献   
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Studies have been carried out on B and T cells in bone marrow and peripheral blood from patients with paraproteinaemia. The peripheral blood of patients with multiple myeloma showed a significant increase of B cells, mainly lymphoid cells bearing immunoglobulins corresponding to the paraproteins, while in patients with benign monoclonal gammopathy only a slight increase of B cells and a moderate decrease of T cells have been found. As to the bone marrow, the B cell population was significantly raised in patients with multiple myeloma, but it remained unchanged in patients with benign monoclonal gammopathy. Our findings may offer a new possibility to distinguish between these two diseases and provide further data to their pathogenesis.  相似文献   
40.
Traditional models of the human language circuitry encompass three cortical areas, Broca’s, Geschwind’s and Wernicke’s, and their connectivity through white matter fascicles. The neural connectivity deep to these cortical areas remains poorly understood, as does the macroscopic functional organization of the cortico-subcortical language circuitry. In an effort to expand current knowledge, we combined functional MRI (fMRI) and diffusion tensor imaging to explore subject-specific structural and functional macroscopic connectivity, focusing on Broca’s area. Fascicles were studied using diffusion tensor imaging fiber tracking seeded from volumes placed manually within the white matter. White matter fascicles and fMRI-derived clusters (antonym-generation task) of positive and negative blood-oxygen-level-dependent (BOLD) signal were co-registered with 3-D renderings of the brain in 12 healthy subjects. Fascicles connecting BOLD-derived clusters were analyzed within specific cortical areas: Broca’s, with the pars triangularis, the pars opercularis, and the pars orbitaris; Geschwind’s and Wernicke’s; the premotor cortex, the dorsal supplementary motor area, the middle temporal gyrus, the dorsal prefrontal cortex and the frontopolar region. We found a functional connectome divisible into three systems—anterior, superior and inferior—around the insula, more complex than previously thought, particularly with respect to a new extended Broca’s area. The extended Broca’s area involves two new fascicles: the operculo-premotor fascicle comprised of well-organized U-shaped fibers that connect the pars opercularis with the premotor region; and (2) the triangulo-orbitaris system comprised of intermingled U-shaped fibers that connect the pars triangularis with the pars orbitaris. The findings enhance our understanding of language function.  相似文献   
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