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1.
Zusammenfassung Die Autoren berichten über dem Formenkreis der zentralen Recklinghausenschen Krankheit zugehörige seltene Geschwulstarten und vergleichen dieselben untereinander. Fall 1 entspricht der als Seltenheit in der Weltliteratur bekannten Foerster-Gagelschen diffusen zentralen Schwannose — obzwar durch die Untersuchung, besonders bei Anwendung der spezifischen Versilberungsmethoden, die morphologischen Züge von der Tumorzelle nachgewiesen werden konnten und hiermit bewiesen wurde, daß es sich um eine diffuse, das ganze Zentralnervensystem überschwemmende Überproduktion von die verschiedenen Entwicklungsstufen der Makroglia verkörpernden Zellen handelt. Vom Gesichtspunkt einer genetischen Deutung ist der Vergleich des 1. Falles mit Fall 2, welcher einen typischen, jedoch stark betonten zentralen Recklinghausen darstellt. Aus alldem wird gefolgert, daß all diese Veränderungen die Ergebnisse einer Hyperfunktion der in der Nähe der Kammeroberfläche tätigen Matrix sein dürften.  相似文献   
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Fibronectin was detected by immunofluorescence technique on the surface of one part of separated normal peripheral blood lymphocytes by using FITC-conjugated anti-human fibronectin antibodies. Approximately one-fifth of isolated B cells and 7% of O cells contained surface-bound fibronectin but T cells failed to stain. There were no detectable free receptors for fibronectin on the surface of lymphocytes of different subsets as it was studied with FITC-labelled purified fibronectin. The percent of B and O cells bearing surface bound fibronectin was markedly decreased in patients with acute and chronic lymphocytic leukemias.  相似文献   
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Salivary thermolytic mechanism (weight of salivary glands, effect of desalivation on water intake and body temperature, grooming activity) as well as escape behaviour and reaction to heat pain were studied in capsaicin-desensitized and control rats exposed to various warm ambient temperatures. Body temperature of the desensitized rats increased more than the controls at all the ambient temperatures studied (32, 34 and 36°C); however, significant differences in the mechanism of salivary cooling were obtained only at 34 and 36°C. Central impairment of saliva spreading in desensitized rats seems evident. Complete surgical desalivation did not increase hyperthermia of control and desensitized animals in warm environments. Therefore other mechanisms, primarily vasodilatatory, must also be involved in the rat's thermolytic normal response. Although desensitized rats did not show a tendency to escape from the warm environment their response to heat pain was normal. In conclusion, it is suggested that heat perception in desensitized animals is impaired; however, the existence of some capsaicin-insensitive thermolytic mechanisms (prone extension of the body) cannot be excluded.Supported by the Scientific Research Council, Ministry of Health, Hungary /4-05-0303-04-2/0/ and MTA-OM-MÉM-EÜM 70.211/79  相似文献   
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The hypo-osmotic swelling test (HOST or HOS test) usually takes into consideration the total HOS response value with no emphasis either on the value of the response subtypes or the response evaluation time. This study investigated the time course of HOS responses and analysed their physiological relevance. Raw semen spermatozoa and Percoll washed spermatozoa were used in the experiment. The morphological changes in the sperm tail were monitored by incubating the spermatozoa in the hypo- osmotic solution for 16 different time periods. The HOS reactive spermatozoa and the type of HOS reaction (swelling subtypes) of the samples subjected to different duration of treatment were identified under a phase contrast microscope. Also the fate of individual spermatozoa in a hypo-osmotic environment were monitored for 30 min. In spermatozoa exposed to a hypo-osmotic solution, the motility lasted usually less than 2 min and motility characteristics were uniquely different from that of the spermatozoa under iso-osmotic conditions. The HOS response development was permanent but the motility loss due to hypo-osmotic shock was reversible up to 1 min of incubation. There was an indication of ordered transition among the HOS swelling subtypes apparently initiating with subtype b destined to c, d, e, f and g. Further, the subtypes a and g showed gradual decrease and increase, respectively, while subtype b showed abrupt initial increase and then gradual decrease. Transition from b to g could be direct or via one or more than one subtypes. Ultrastructure based analysis indicated that HOS response subtypes are the apparent reflection of the differences in the cytoskeletal assembly of the sperm tail and thus may be identifying different physiological variants in the sperm population. These results indicate that shorter incubation is essential to document the kinetics of various HOS responses but the conventional HOS test misses these important HOS features because of lengthy incubation. Since the time course of ordered transition of HOS responses will vary more than the total HOS response in semen of different aetiologies, the importance of HOS response subtypes and response evaluation time should be taken into consideration when applying HOS test.   相似文献   
7.
Visual information processing is impaired in schizophrenia patients and their biological relatives. The authors measured vernier thresholds in 72 schizophrenia patients, their 86 siblings, and 60 healthy control subjects. Subjects were asked to detect the direction of the horizontal displacement of 2 stimuli (left or right). During magnocellular (M) pathway tests, stimuli were dots with low contrast (5%) or counterphase-modulated gratings (25 Hz). For parvocellular (P) pathway tests, isoluminant blue-red dots with yellow-green background were used. Results revealed that patients with schizophrenia and their siblings were more impaired in M pathway conditions than in P pathway conditions. There was no color-specific impairment. The patients and their siblings displayed lower performances on tests of executive functions, psychomotor speed, and verbal memory compared with the controls. Visual-perceptual and neuropsychological data did not correlate. In conclusion, M pathway dysfunction is a potential endophenotype of schizophrenia.  相似文献   
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Yersinia pestis, the etiologic agent of plague is a highly invasive organism being able to invade non-phagocytic epithelial cells. Its plasminogen activator (Pla), encoded by the pPCP1 plasmid plays a pivotal role in internalisation of bacteria by HeLa cells. The aim of this study was to analyse the intracellular signalling processes and cytoskeletal rearrangement events associated with invasion. Wortmannin caused a 50% decrease of invasiveness at 50nM concentration pointing to the involvement of phosphatidyl-inosinol-4 kinase (PtINs4). Pre-treatment with staurosporin, a potent inhibitor of protein kinases (PKs) and with genistein, a specific tyrosine kinase inhibitor decreased the number of internalised bacteria about seven-fold and two-fold, respectively, indicating the involvement of PKs including tyrosine kinases in Pla-mediated internalisation. Cytochalasin D, an actin polymerisation inhibitor, C3 exoenzyme of Clostridium botulinum, a specific inhibitor of small GTPase Rho, and NDGA, a 5-lipoxygenase inhibitor also involved in Rho activation strongly reduced the number of internalised bacteria revealing the role of cytoskeletal events in the invasion process. All the tested inhibitors changed the invasion but not the adhesion pattern of the Pla producing recombinant strain. Actin rearrangement could also be visualised also with rhodamin-phalloidin staining.  相似文献   
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This study investigated the relationship between theory of mind (ToM) deficits and visual perception in patients with schizophrenia (N=52; 17 remitted and unmedicated) compared with healthy controls (N=30). ToM was assessed with the Eyes Test, which asked participants to choose which of 4 words best described the mental state of a person whose eyes were depicted in a photograph. Visual perception was evaluated with form and motion coherence threshold measurements. Results revealed that patients with schizophrenia (both remitted and nonremitted) showed deficits on the Eyes Test and the motion coherence task. ToM dysfunctions were associated with higher motion coherence thresholds and more severe negative symptoms. This suggests that ToM deficits are related to motion perception dysfunctions, which indicates a possible role of motion-sensitive areas in the pathophysiology of schizophrenia.  相似文献   
10.
The effects of vitamin A were studied on the basal and maximal gastric secretory responses of 12 patients; and on healing in 60 patients with chronic gastric ulcer. The effect of vitamin A on ulcer healing was evaluated by a multiclinical, multicentre, randomized, prospective study in which the patients were divided into three groups. In group A the patients were treated with antacids only; in group B the patients were given antacids plus vitamin A (in doses of 3 X 50.000 U orally); and in group C the patients received antacids, vitamin A plus cyproheptadine (in doses of 3 X 4 mg orally). The treatment lasted four weeks. At the beginning and the end of treatment endoscopies were performed and ulcer sizes were measured planimetrically. Various other parameters such as ulcer index, antacid consumption and laboratory parameters were also evaluated during the four-week treatment. It was observed that: (i) vitamin A (given in doses of 100.000 U i.m.) decreased neither basal nor maximal gastric secretory responses; (ii) the number of patients with completely healed gastric ulcer was significantly higher (P less than 0.05) in groups B and C than in group A; (iii) the extent of ulcer reduction was significantly higher (P less than 0.01) in groups B and C than in group A; (iv) no significant changes were observed in ulcer index and antacid consumption during the four-week treatment in the different groups of patients; (v) the reduction of ulcer size was significantly greater (P less than 0.01) in the group treated with antacids plus vitamin A than in the group treated with antacids only, at two weeks of treatment.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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