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991.
The present study was undertaken to evaluate whether the persistent hypoperfusion following cortical spreading depression (CSD) in rat brain was accompanied by alterations of regional cortical glucose consumption (rCGU). rCGU was measured using 2-deoxy-[14C]glucose and autoradiography at 15–60 min after single CSD episodes. rCGU did not differ in cortical regions invaded by CSD as compared to the contralateral side and to sham-treated rats. The results suggested impairment of the metabolism-flow couple after CSD. 相似文献
992.
Summary Conjunctival, muscle, and peripheral artery biopsies were examined by light and electron microscopy in a patient with clinically diagnosed Rett syndrome. In capillaries, amorphous and membranous electron-dense deposits were observed (a) endoluminally attached to endothelial cell membranes, (b) within junctional clefts of adjacent endothelial cells, and (c) at abluminal sites of endothelial cells. In addition, electron-dense deposits layiisolated or inside multivesicular bodies in endothelial cells and pericytes. These findings have not been reported before in Rett syndrome. They were not seen in agematched normal or pathological control cases and are suggested to indicate deposition of an as yet unknown lipidic plasma component possibly in association with impairment of the blood-tissue barrier.Supported in part by the Deutsche Forschungsgemeinschaft, Di-386/1-1 相似文献
993.
Summary Leu-19 antigen is a 200–220 kDa surface glycoprotein, initially detected on natural killer (NK) cells exhibiting non-major histocompatibility complex-restricted cytotoxity. Using a monoclonal antibody (mAb) directed against the Leu-19 molecule, we were unable to identify NK cells immunohistologically in cryostat sections of neuroectodermal tumors. Instead, mAb Leu-19 cross-reacted with the surfaces of the tumor cells, except for melanomas. It stained mesodermal tumor cells less intensely and did not stain those of carcinoma metastases. In three plasmocytomas, cells were observed, most likely NK cells, which extend Leu-19-positive cell processes towards to the unstained tumor cells. Furthermore, the Leu-19 antigen was identified on physiological tissues, especially on all neuroendocrine cells analyzed. The cross-reactions observed with Leu-19 mAb were confirmed using mAb NKH-1, which is also directed against the Leu-19 molecule. Thus, the expression of Leu-19 on neuroectodermal cells is another example of antigen sharing between specialized immune cells and the nervous system. 相似文献
994.
H. Darius V. Hossmann K. Schrör 《Journal of molecular medicine (Berlin, Germany)》1986,64(12):545-551
Summary The dose-dependent inhibition of platelet aggregation by the chemically stable, prostacyclin-mimetic, iloprost, was studied in patients suffering from stage II–III peripheral arterial obliterative disease (PAOD). The study was designed as a randomized placebo-controlled cross-over trial. Iloprost was administered i.v. to six patients at doses of 0.5, 1.0, 2.0 or 3.0 ng/kg×min for 4 h, with an interval of 2–3 days between the infusions. During iloprost infusion, systolic and diastolic arterial blood pressure, heart rate and blood flow in the affected limb remained unchanged. In contrast, there was a considerable, dose-dependent inhibition of ADP- and thrombin-induced platelet aggregation and secretion ex vivo at doses of 0.5–2.0 ng/kg×min iloprost, indicating that iloprost reduced platelet stimulation by 50%–70%. The antiplatelet action of iloprost remained unchanged during infusion but ceased with 2 h after administration had ended. The agent was tolerated by the patients without unacceptable side-effects at doses up to 2 ng/kg × min. It is concluded that iloprost administered i.v. at doses of 1–2 ng/kg×min in patients with stage II–III PAOD does not involve haemodynamic side-effects and might be considered an effective antiplatelet agent.Abbreviations ADP
Adenosinediphosphate
- PGI2
Prostacyclin
- PRP
platelet rich plasma
- TXA2
Thromboxane A2
- 12-HPETE
12-hydroperoxy-eicosatetraenoic acid
Presented in part as a preliminary report at the II. International Prostaglandin Symposium, Nürnberg-Fürth, 1984 相似文献
995.
A. S. Schröder-Gravendyck E. F. Kaleta R. E. Marschang M. Gravendyck 《Avian pathology》2001,30(5):551-558
Thirty-one viruses were isolated from 15 different psittacine species. They were all identified as herpesviruses on the basis of chloroform sensitivity, inhibition of replication in cell cultures by 5-iodo-2'-deoxyuridine and morphology by electron microscopy. DNA from all 31 field isolates of psittacine herpesviruses (PsHV) was analysed by cleavage with restriction endonucleases EcoRI, PstI, and BglII. Using this technique, 12 different restriction patterns were recognizable. In previous work, we have differentiated PsHV strains according to their serological interrelationships. Restriction endonuclease profiles confirmed the results of conventional serogrouping but additional differences were observed among the five established serological subtypes. Using this method, it was possible to demonstrate a spontaneous reinfection of parrots in an aviary with a serologically and genetically different PsHV strain 4 years after the first outbreak of Pacheco's parrot disease (PPD). The results of this study reaffirm that antigenetically and genetically different PsHV exist and can cause PPD. 相似文献
996.
Jan Folkvard Evensen Sophie Dorothea Foss Kjell Kjellevold Hans Henrik Lien 《Journal of surgical oncology》1987,36(3):166-169
Risk factors, their interrelationship, and prognostic relevance for seminoma stage II disease have been examined. The size of the primary tumor was significantly correlated with the pT category, as was the presence of tumor invasion of small vessels. The pT category was correlated neither with clinical substage nor relapse rate. There was a poorer 3-year survival for anaplastic seminomas as compared to that of classical seminomas; the difference was not significant. The 5-year survival for seminomas rich in lymphocytes was better than those of poor lymphocytic infiltration, but this difference also was not significant. No difference in survival or relapse rate was found between HCG-producing and HCG-nonproducing seminomas. 相似文献
997.
Condensed images for evaluating gastric motility patterns 总被引:1,自引:0,他引:1
A condensed imaging technique was applied to gastric emptying studies to investigate (a) whether different types of motility disorders may be distinguished by characteristic image patterns and (b) whether the findings obtained provide additional information compared to standard quantitative measurements. Condensed images and quantitative data of gastric emptying were evaluated in 75 consecutive patients with normal function (n = 16) and various disorders (n = 59) such as peptic ulcer, postvagotomy, pyloric obstruction, dumping syndrome, gastroparesis etc. Condensed images were generated from a gastric region of interest. They display the distribution and behaviour of a radioactive test meal in a space-time matrix, whose horizontal and vertical dimensions are temporal and spatial, respectively. As shown in a series of representative examples condensed images disclose a variety of well-defined image patterns reflecting different pathophysiological mechanisms. This qualitative characterization of gastric emptying patterns provided in 34 of the 75 patients (45%) important new information compared to quantitative data. The application of condensed imaging techniques to gastric emptying studies (complementary to quantitative measurements) may, therefore, enhance the diagnostic value of scintigraphic techniques. 相似文献
998.
A prophylactic vaccine represents a major hope for the control of sexually transmitted diseases. The current general vaccine strategies and the status of vaccine development against infections with Neisseria gonorrhoeae, Treponema pallidum, Chlamydia trachomatis and Herpes simplex virus are described. Vaccines consisting of whole infectious agents are replaced by protective subunits. A subunit vaccine has the advantage to be free from other components, which are not relevant for protection and which may confer unwanted side effects. At the present time vaccine development against infections with Neisseria gonorrhoeae and Herpes simplex virus seems to be the most progressed. With monoclonal antibodies several surface components could be identified, which are of importance for the pathomechanism. With Treponema pallidum and Chlamydia trachomatis the development is delayed by unsolved problems of immunity. For the production of vaccines molecular-biologic methods, like protein synthesis or gene-cloning will be used. Genetically modified live vaccines or polytope hybrid vaccines will gain importance in the future. 相似文献
999.
Henrik rbEk Andersen Per Erik Jrgensen Linda Bardram Linda Hilsted 《Clinical endocrinology》1990,33(6):771-775
A total of 79 consecutive patients with pituitary tumours were screened for multiple endocrine neoplasia type 1 (MEN-1). The 79 patients included 21 patients with acromegaly, nine with Cushing's disease, 18 with prolactinomas, three with mixed pituitary adenomas (GH and PRL), and 28 patients with no detectable hypersecretion of hormones. The screening consisted of: (1) a family history, (2) a uniform medical history of the patient using a standard questionnaire, and (3) hormonal evaluation including measurements of the serum levels of insulin, gastrin, glucagon, somatostatin, vasoactive intestinal polypeptide and pancreatic polypeptide. Ionized calcium and glucose concentration in serum were also measured. We found no patients with the MEN-1 syndrome. In one patient, we found a transient elevation of serum concentrations of pancreatic polypeptide for which we have no explanation. In another patient, the serum gastrin concentration was elevated secondary to achlorhydria. No other endocrine disorders were found, and no patients had relatives with recognized endocrine pancreatic tumours, primary hyperparathyroidism (HPT), or pituitary adenomas. 相似文献
1000.
In vivo induction of anergy in peripheral V beta 8+ T cells by staphylococcal enterotoxin B 总被引:36,自引:14,他引:22
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Purification of monocyte-derived NAP-1/IL-8 by preparative reversed-phase (RP)-HPLC led to the detection of a second peak with polymorphonuclear leukocyte (PMNL)-activating (degranulation, chemotaxis) properties. The monokine responsible for this biological activity, which we tentatively termed NAP-3, could be purified to homogeneity by three different RP-HPLC steps. Tricine-SDS-PAGE analysis gave a single line at Mr 5.3 kD (NAP-1/IL-8 = 5.8 kD). NH2-terminal amino acid sequence analysis read as a major sequence (ASVATELRXCXLQT. .), which shows greater than 40% homology to that of NAP-1/IL-8. The sequence is identical to that found for the 13-kD moiety of melanoma growth stimulating activity (MGSA) and the product of the oncogene gro. Determination of neutrophil chemotactic activity of NAP-3 revealed a typical bell-shaped dose-response curve (ED50 = 2 ng/ml) with no significant neutrophil chemotactic activity at doses greater than 200 ng/ml. Also, in cytochalasin B-pretreated PMNL, NAP-3 elicited release of myeloperoxidase and beta-glucuronidase. Crossdesensitization studies in PMNL enzyme release revealed crossreactivities with the NAP-1/IL-8-R on PMNL. NAP-3 (MGSA/gro) appears to represent the first member of the novel supergene family of beta-thromboglobulin-like host defense cytokines, which expresses both mitogenic as well as proinflammatory properties at the nanogram level. 相似文献