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41.
42.
The ischaemic cerebral attack is a disease prevailingly of older age. Its prognosis is distinguished by a mortality rate as high as ever. From 1975 to 1985, 520 patients with ischaemic cerebral attack have been treated in hospital, with specific acute therapy changing from the so-called vasodilator therapy via osmotherapy into haemodilution therapy with lowmolecular dextrane. Since during vasodilator therapy any early mobilisation nor continuous physiotherapy were carried out and the patients prevailingly died of bronchopneumonia, the significantly lower mortality rate under osmotherapy and haemodilution therapy cannot be attributed to the specific drug therapy. In all probability it is a result of the improvement of care and of the active early mobilisation of the patients. 相似文献
43.
Dr. S. Fuchs Ch. Jürgens A. P. Schulz M. E. Wenzl D. Wolter 《Trauma und Berufskrankheit》2005,7(2):83-88
Zusammenfassung Winkelstabile Plattenfixateur-interne-Systeme haben in den letzten 20 Jahren zunehmend an Bedeutung gewonnen. Die aus der Winkelstabilität resultierende flächenhafte Krafteinleitung und gleichmäßigere Kraftverteilung führen zu einer besseren Knochenbruchheilung insbesondere im metaphysischen Bereich und bei Osteoporose. Bei Marknagelsystemen ist die Winkelstabilität bislang nur partiell verwirklicht. Der vorgestellte winkelstabile Tibiamarknagel realisiert an jedem einzelnen Bolzen eine Winkelstabilität mit dem einliegenden intramedullären Kraftträger. Von Februar 2002–August 2004 wurden 21 Patienten mit ihm behandelt. In 13 Fällen wurden Frakturen stabilisiert, 6 Patienten hatten Fehlstellungen, 2 Patienten Pseudarthrosen. Zum Nachuntersuchungszeitpunkt waren alle Behandlungen abgeschlossen. Postoperative Komplikationen traten nicht auf. In allen Fällen wurde eine vollständige Durchbauung erreicht. In 6 Fällen fand sich radiologisch eine verzögerte Knochenbruchheilung. Die ersten klinischen Erfahrungen mit dem winkelstabilen Tibiamarknagel zeigen, dass dieser aufgrund der höheren Primärstabilität insbesondere im metaphysären Knochenbereich mit kurzen Fragmenten sowie bei Osteoporose Vorteile gegenüber anderen nichtwinkelstabilen oder nur partiell winkelstabilen Marknagelsystemen erbringt. Die verzögerten Knochenbruchheilungen bedürfen weiterer klinischer und biomechanischer Untersuchungen. 相似文献
44.
45.
Rüdiger Schulz 《Naunyn-Schmiedeberg's archives of pharmacology》1988,338(6):644-648
Summary Chronic activation of opioid receptors results in the development of tolerance and dependence. Tolerance may be confined to a single receptor type and thus has been termed selective tolerance. The present investigation reveals that prolonged activation of an inhibitory acting receptor type not only results in dependence associated with this receptor but also brings about cross-dependence. Cross-dependence involves both opioid receptors as well as non-opioid receptors, e. g. adrenoceptors. The experimental design employed did not permit conclusions to be drawn about whether those receptors exhibiting cross-dependence also developed tolerance. Regardless of the receptors and their specific subsequent transduction systems, all the receptors which showed dependence and cross-dependence proved sensitive to pertussis toxin, suggesting a critical function of GTP-binding proteins for the development of not only opioid dependence but also for drug dependence in general. Since multiple transmitter receptors may converge on the same ion channel, the concept of convergent dependences may be linked to GTP-binding proteins. However, no conclusions can be drawn with regard to the precise biochemical mechanisms underlying dependence.
Send offprint requests to R. Schulz at the above address 相似文献
46.
A subgroup of patients with personality disorders from the DSM-III-R (American Psychiatric Association 1987) "flamboyant" cluster is characterized by repetitive self-injurious behavior (SIB) apparently not motivated by suicidal intent. After describing the clinical and demographic characteristics of these patients, the clinical and preclinical evidence suggesting the involvement of endogenous opiate systems in this behavior is reviewed. Patients with personality disorders and SIB have been found to have elevated levels of plasma beta-endorphin. However, the available evidence is not sufficient to show whether this is a cause of or a consequence of SIB. Behavioral stereotypies resulting in self-injury in animals and SIB in mentally retarded patients have been shown to be abolished by opiate antagonist administration in a significant proportion of both groups. The available evidence suggests that clinical trials of oral opiate antagonist drugs should be undertaken because of the promise such drugs have in the treatment of this sometimes life-threatening disorder. 相似文献
47.
In-vitro maturation of human germinal vesicle stage oocytes: role of cumulus cells and epidermal growth factor in the culture medium 总被引:21,自引:6,他引:21
Goud PT; Goud AP; Qian C; Laverge H; Van der Elst J; De Sutter P; Dhont M 《Human reproduction (Oxford, England)》1998,13(6):1638-1644
In-vitro maturation (IVM) of oocytes is a promising technique to reduce the
costs and avert the side-effects of gonadotrophin stimulation for in-vitro
fertilization (IVF). The pregnancy rates from oocytes matured in vitro are
much lower than those of in-vivo stimulation cycles indicating that
optimization of IVM remains a challenge. Therefore, we investigated the
effect of supplementation of the medium with gonadotrophins, oestradiol and
epidermal growth factor (EGF) and the effect of retaining or removing the
cumulus cells on nuclear and cytoplasmic maturation of immature oocytes.
Human germinal vesicle (GV) oocytes obtained after gonadotrophin
stimulation for intracytoplasmic sperm injection (ICSI) were cultured in a
complex defined medium either supplemented with gonadotrophins, oestradiol
and physiological concentrations of EGF (2 ng/ml) or gonadotrophins and
oestradiol alone. The cumulus cells were either removed or kept intact. In
GV stage oocytes cultured without cumulus (group I) significantly more
oocytes reached the metaphase II (MII) stage at 30 h in media supplemented
with EGF (64.3 versus 33.9%, P < 0.003). For oocytes cultured with
intact cumulus (group II), more oocytes reached MII at 30 h than in group
I, but there was no difference in medium with or without EGF
supplementation (81.8 and 79.8% respectively). Cytoplasmic maturation of
MII oocytes was judged from their capability to activate and fertilize
after ICSI. In group I, the rates of activation and normal fertilization
were similar. However, in group II, significantly more oocytes underwent
normal fertilization in the EGF-supplemented than the unsupplemented group
(71.7 versus 45.6%, P < 0.05). The cleavage rates of the fertilized
oocytes were similar in the sibling oocyte subgroups cultured with or
without EGF supplementation, but the overall cleavage rates were higher in
cumulus-intact compared to cumulus-denuded oocytes (88.9 versus 47.8%, P
< 0.001). Thus, supplementation of the maturation medium with EGF and
maintenance of the cumulus during culture improve the nuclear and
cytoplasmic maturation of human oocytes in vitro.
相似文献
48.
IL-18 induces the differentiation of Th1 or Th2 cells depending upon cytokine milieu and genetic background 总被引:7,自引:0,他引:7
Xu D Trajkovic V Hunter D Leung BP Schulz K Gracie JA McInnes IB Liew FY 《European journal of immunology》2000,30(11):3147-3156
The functional division of CD4(+) T cells into Th1 and Th2 subsets is generally accepted but the mechanisms leading to their preferential induction remain elusive. Cytokines are considered the main determining factors in the initial differentiation of precursor T cells into these distinct subsets. Thus, IL-12 drives Th1 cells whereas IL-4 drives Th2 cells. Recently IL-18, originally designated as IFN-gamma-inducing factor, has been reported to synergize with IL-12 in the induction of Th1 cells. We report here that IL-18 can also induce T cells to differentiate into Th2 cells, in the presence of TCR activation, either alone or together with IL-4. This effect of IL-18 is mediated primarily on CD4(+) T cells compared with CD8(+) T cells and is inhibited in the presence of IL-12. IL-18, however, has no effect on functionally committed Th2 cells.( )Moreover, the effect of IL-18 on Th2 cell development is differentially manifest in different mouse strains, suggesting profound underlying genetic influences. BALB/c mice infected with Leishmania major and treated with recombinant IL-18 developed exacerbated disease and enhanced Th2 response compared with untreated controls. These data therefore provide a novel mechanism for Th2 cell development. Thus, IL-18, a cytokine constitutively expressed by cells of the innate response, is capable of inducing Th2 cell differentiation in the absence of IL-4. 相似文献
49.
Thierbach R Schulz TJ Isken F Voigt A Mietzner B Drewes G von Kleist-Retzow JC Wiesner RJ Magnuson MA Puccio H Pfeiffer AF Steinberg P Ristow M 《Human molecular genetics》2005,14(24):3857-3864
We have disrupted expression of the mitochondrial Friedreich ataxia protein frataxin specifically in murine hepatocytes to generate mice with impaired mitochondrial function and decreased oxidative phosphorylation. These animals have a reduced life span and develop multiple hepatic tumors. Livers also show increased oxidative stress, impaired respiration and reduced ATP levels paralleled by reduced activity of iron-sulfur cluster (Fe/S) containing proteins (ISP), which all leads to increased hepatocyte turnover by promoting both apoptosis and proliferation. Accordingly, phosphorylation of the stress-inducible p38 MAP kinase was found to be specifically impaired following disruption of frataxin. Taken together, these findings indicate that frataxin may act as a mitochondrial tumor suppressor protein in mammals. 相似文献
50.