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31.
Ohne ZusammenfassungBenutzte Symbole und Abkürzungen NNR Nebennierenrinde - DOCA Desoxycorticosteronacetat - K i intracelluläres Kalium (sinngemäß für Natrium) - K a extracelluläres Kalium (sinngemäß für Natrium) - Q Ladung - E m Membranruhepotential - m Zeitkonstante der Membran - R m Membranwiderstand - C m Membrankapazität  相似文献   
32.
The present report describes a case of Mycobacterium tuberculosis infection in an African Grey parrot (Psittacus erithacus erithacus) kept as a pet bird. Diagnosis was confirmed by microbiologic and pathologic results, and indicated a human–avian transmission. Clinical signs included sublingual nodules resulting in anorexia and signs of osteolysis in the long bones. Proliferation consisted of several nodules with small greenish-caseous foci in cross-section and revealed a severe granulomatous inflammation without intralesional acid-fast rods. M. tuberculosis was cultured from a pooled sample of sublingual and liver nodules, and was confirmed via polymerase chain reaction. Transmission between men and parrot was proved by spoligotyping pattern analysis. The absence of facial skin lesions and acid-fast rods within the tubercles is contrary to previous publications of tuberculosis in birds. This disease in a common pet bird species is of zoonotic importance, and those parrots with close contact to owners suffering from tuberculosis may serve as a potential reservoir for human infection.  相似文献   
33.
Summary Anatomic variations are important in preendoscopic CT evaluation of the paranasal sinuses. In this study, we investigated whether the superior turbinate could become pneumatised like the middle turbinate, pneumatisation of which is well-known. Images of 52 patients who underwent CT examination prior to endoscopic sinus surgery and who had normally aerated posterior ethmoidal cells and an unobscured nasal cavity were retrospectively evaluated. The patients were 12–68 years old (median age, 35 years); 28 were women and 24 were men. Pneumatisation of the superior turbinates was graded in two groups as minimal or marked. Pneumatisation was evident in 25 patients (48%). 13 unilateral (25%), 8 bilateral (15%) pneumatisations were detected in the group graded as minimal, whereas 1 unilateral and 3 bilateral pneumatisations were present in the markedly (8%) pneumatised group of patients. Superior turbinates were seemingly aerated through the posterior ethmoid cells. The superior turbinates can be pneumatised as the middle turbinate is a not frequent anatomic variation that should be taken into account in preendoscopic CT evaluation of the paranasal sinuses.
La pneumatisation du cornet nasal supérieur : une variation anatomique courante ?
Résumé Les variations anatomiques sont importantes à connaitre dans le cadre du bilan tomodensitométrique précédant une chirurgie endoscopique des sinus paranasaux. Dans cette étude, nous avons recherché si le cornet nasal supérieur pouvait être pneumatisé comme l'est le cornet nasal moyen, entité anatomique bien connue. Les images de 52 patients ayant eu une tomodensitométrie avant chirurgie endoscopique et montrant des cellules ethmoïdales postérieures normalement pneumatisées et une cavité nasale nonopaque, ont été évaluées rétrospectivement. Les patients, 28 femmes et 24 hommes, étaient âgés de 12 à 68 ans (moyenne : 35 ans). La pneumatisation du cornet nasal supérieur a été classée en deux groupes; minime et prononçée. Cette pneumatisation était patente chez 25 patients (48 %). Treize pneumatisations unilatérales (25 %) et 8 pneumatisations bilatérales (15 %) furent retrouvées dans le groupe présentant une pneumatisation minime alors que 1 pneumatisation unilatérale et 3 bilatérales (8 %) étaient présentes dans le groupe dont la pneumatisation était plus marquée. Les cornets nasaux supérieurs semblaient être aérés par les cellules ethmoïdales postérieures. Les cornets nasaux supérieurs peuvent être pneumatisés, comme le sont les cornets nasaux moyens, avec une fréquence non-exceptionnelle. Cette variation anatomique mérite d'être prise en considération dans le bilan tomodensitométrique précédant toute chirurgie endoscopique des sinus paranasaux.
  相似文献   
34.
Nawroth F  Foth D  Stute P  Schmidt T  Römer T 《Maturitas》2000,37(2):129-132
Our report concerns a patient with a climacterium praecox and an X-chromosomal anomaly (86% 46, XX; 7% 47, XXX; 7% 45, X0) desiring to give birth. She conceived once after down-regulation of the gonadotrophins by means of a cyclical hormone replacement therapy followed by gonadotrophin stimulation, as well as a second time under down-regulation with a GnRH-analogue and gonadotrophin stimulation. On the basis of the case report and of the literature, a possible interval therapy in such a patient, especially one even with increasing ovarian insufficiency, will be portrayed and discussed.  相似文献   
35.
36.
Felix  S. B.  Baumann  G.  Hashemi  T.  Niemczyk  M.  Ochsenfeld  G.  Ahmad  Z.  Shirani  S.  Blömer  H. 《Inflammation research》1991,33(3-4):349-358
Summary In vivo anaphylaxis is associated with respiratory distress and cardiovascular failure. The present investigation was designed to further characterize respiratory and cardiac anaphylactic events. In guinea pigs, sensitization was produced by subcutaneous application of ovalbumin together with Freund's adjuvant. Fourteen days after sensitization, the effects of an intravenous infusion of ovalbumin were tested in the anesthetized artificially ventilated guinea pigs. The renewed application of the antigen induced an initial increase of left ventricular pressure which was followed by a rapid decrease 5 min after antigenic challenge. Enddiastolic left ventricular pressure increased within 3 min, thus indicating left ventricular pump failure. In the same time range, ECG recordings uniformly showed signs of acute myocardial ischemia. In addition, heart rate steadily decreased. All animals died within 15 min. Simultaneously with cardiac anaphylactic malfunction, severe arterial hypoxia and carbon dioxide retention occurred, revealing respiratory distress.Histamine is known as a potent bronchoconstrictor via histamine H1-receptor stimulation. Administration of H1-recpetor antagonists to improve respiration may therefore provide further information on the contribution of pulmonary malfunction to anaphylactic cardiovascular shock. Therefore, additional experiments were performed with sensitized guinea pigs pretreated with the histamine H1-receptor blocker mepyramine. In these experiments the antigenic challenge induced a dissociation of cardiac and respiratory manifestation of anphylaxis. Despite inhibition of hypoxia and carbon dioxide retention, left ventricular pump failure and occurrence of myocardial ischemia were delayed but not suppressed.It is concluded that histamine is an important mediator of anaphylactic respiratory distress. However, vasoactive anaphylactic mediators other than histamine are primarily involved in anaphylactic cardiac malfunction occurring during the later phase of systemic anaphylaxis.Supported by grant Fe 250/1-1 from the Deutsche Forschungsgemeinschaft (DFG).  相似文献   
37.
Studies on smooth muscle cell differentiation and those on vascular development in mouse and humans have long been hampered by the lack of suitable markers. Here we describe a novel, large isoform of smoothelin, a structural protein of differentiated, contractile smooth muscle cells. The protein, which is highly conserved in mouse and humans, shows homology with other cytoskeleton-associated smooth muscle cell proteins and contains an actinin-type actin-binding domain. Northern blot analysis from various mouse organs identified short and long smoothelin mRNA forms, which exhibit distinct tissue expression patterns. The short form is highly expressed in visceral muscle tissues such as intestine and stomach and is not detectable in brain, while the long mRNA form is expressed in all vascularized organs. These results may provide new tools and approaches to study both smooth muscle cell differentiation and proliferative vascular disease. Received: 25 August 1998 / Accepted: 19 October 1998  相似文献   
38.
One of the consequences of the heat shock response is a shutdown of pre-mRNA splicing, a phenomenon that can be reproduced in extracts prepared from heat-shocked cells. The block in splicing occurs before the covalent modifications that generate spliced mRNA at the level of spliceosome formation. We have used extracts prepared from heat-shocked cells as a complementation system to characterize and partially purify a protein factor that is inactivated during the in vivo heat shock. The activity functions in the formation of the active spliceosome by assembling U4/U6 and U5 snRNPs into a triple snRNP particle. The factor appears to be different from previously isolated splicing factors and is functionally equivalent to several polypeptides that are specifically associated with the purified triple snRNP but not with individual U4/U6 or U5 snRNPs. Our data confirm the hypothesis that U4/U6 and U5 snRNPs enter the spliceosome as a triple snRNP complex and show for the first time a function of specific snRNP-associated polypeptides in the mammalian splicing pathway.  相似文献   
39.
Summary In this study the spontaneous activities of prescapular lymph nodes, which were isolated from calves, goats and sheep and mesenteric lymph nodes of guinea-pigs were recorded and analysed in the frequency domain. Stretch-evoked contractions of the mesenteric lymph nodes were also recorded and their frequency characteristics analysed.The preparations were placed in a Krebs solution which was kept at 37° C and bubbled continuously with a mixture of 95% O2 and 5% CO2. The tension changes occurring in the lymph nodes were recorded. The patterns obtained were initially transformed into numerical values which were then used to obtain autocorrelation functions and power spectra, according to the time series analysis method. A passive stretch of 100 s duration was applied to the mesenteric lymph nodes and the responses were examined using the transient response-frequency characteristics method.It was observed that prescapular and mesenteric lymph nodes had spontaneous activities due to the contractions of the smooth muscles within the nodes. A frequency analysis of these contractions indicated that at least three contractile components were responsible for the contractions; these components contract within the frequency bands of 0.01–0.04 Hz, 0.05–0.07 Hz and 0.09–0.14 Hz respectively. It was also observed that the spontaneous activities could be regulated and synchronized by stretch. It is suggested that these contractions of the lymph nodes play an essential role in lymph propulsion within the nodes.  相似文献   
40.
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