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991.
992.
Cytogenetic analysis of a uterine lipoleiomyoma.   总被引:2,自引:0,他引:2  
We cytogenetically analyzed a uterine lipoleiomyoma. A primary chromosomal abnormality, t(12;14), was found in all 62 cells studied. A secondary change involving chromosomes 1 and 5 was detected in 15 of 62 cells. These findings suggest that lipoleiomyomas share the same chromosomal abnormalities found in common leiomyomas. We speculate that the secondary chromosomal change involving chromosomal 5 may be responsible for the lipomatous change.  相似文献   
993.
994.
Summary A case of malignant endocrine tumour of the jejunum, associated with severe duodenal ulcer is described. The tumour and a local metastasis were examined by immunohistochemistry and found to contain abundant somatostatin-immunoreactive cells together with less numerous cells displaying gastrin immunoreactivity. This is to our knowledge the first case of intestinal somatostatinoma. The presence of gastrin cells in the tumour may explain the ulcer diathesis.  相似文献   
995.
The sera of ten patients with unexplained hypoglycaemia were examined for antibodies to pancreatic islets. Antibodies to pancreatic A, B and D cells (ICAb) were detected in one patient with an associated gastrointestinal tumour.  相似文献   
996.
997.
Calcium-activated chloride currents were studied by the patch-clamp technique in vascular smooth muscle cells (VSMC) isolated from human mesenteric arteries. Bath application of 20 mM caffeine caused the cell membrane to depolarize by a calcium-activated inward current that peaked to –654±230 pA (holding potential –50 mV). Cell-attached, at the same time inwardly directed single-channel currents were detected with an amplitude of –0.22 pA. In open-cell-attached patches channel activity was triggered by elevating [Ca2+]i to 10 M. At –60 mV the mean amplitude of the current was –0.24 pA and the mean open time of the channels was 28 ms. Plotting the amplitude of the current versus the test potential yielded a single-channel conductance of 2.8±0.5 pS. The currents disappeared when [Cl] was reduced from 150 mM to 5 mM at the cytosolic side of the inside-out patch at a holding potential of -60 mV (calculated reversal potential –58 mV) suggesting that the calcium-activated current was a chloride current. This suggests that, in human mesenteric VSMC, elevation of [Ca2+]i activates a low-conductance chloride channel, which may mediate the agonist-induced depolarization of the cell membrane.  相似文献   
998.
Between 1983 and 1988, subgroups and serotypes were determined for 907 of 1,084 clinical specimens of rotaviruses collected in various countries of Europe, North and South America, Africa, and Asia. Enhanced enzyme immunoassays based on monoclonal antibodies specific for rotavirus proteins VP6 and VP7 were used. Significant differences in the prevalent serotypes were detected from year to year in the United Kingdom and Brazil and also in different countries during the same year. Throughout the study, rotavirus serotype 1 was detected most often (53.8%), followed in frequency by serotype 2 (17.8%), serotype 3 (12.1%), serotype 4 (11.1%), and serotypes other than 1 to 4 (5.1%). No individual serotype was found to predominate consistently in any one location. In the United Kingdom, rotavirus serotypes varied in prevalence in a regular but not predictable way. We suggest that a similar epidemiology might be found in other settings. Seventeen unusual strains were detected. Of these, five strains did not react with reference monoclonal antibodies specific for subgroup I and subgroup II, but they reacted with rotavirus group A-specific polyclonal and monoclonal antibodies; four strains were of subgroup II, serotype 2, and at least one had a "long" electropherotype; two strains were of subgroup I, serotype 2 with a long electropherotype; and one strain was of subgroup I, serotype 3. Five group C rotaviruses were detected.  相似文献   
999.
Human polymorphonuclear leukocyte interaction with cyclosporine A.   总被引:4,自引:1,他引:4       下载免费PDF全文
The effects of cyclosporin A (cyA) on human polymorphonuclear leukocyte function, including phagocytosis, its associated metabolic burst, bacterial killing, and chemotaxis, were evaluated. Both Pseudomonas aeruginosa and Staphylococcus aureus were used as test particles. Polymorphonuclear leukocytes incubated in 10 and 50 micrograms of cyA per ml behaved normally with respect to phagocytosis and hexose monophosphate shunt activity at both high (10:1) and low (2:1) S. aureus/leukocyte ratios. With a small bacterial inoculum, killing of S. aureus was slightly impaired at early times only in the presence of 50 micrograms of cyA per ml. Phagocytosis and killing of P. aeruginosa with both large and small bacterial inocula were unaffected by cyA. Chemotaxis was within normal limits under all conditions. In addition, polymorphonuclear leukocytes from four renal transplant recipients receiving both cyA and prednisone demonstrated normal metabolic bursts and bacterial killing with both small and large inocula of S. aureus.  相似文献   
1000.
Zusammenfassung Sieben Gruppen von Meerschweinchen zu je 15 Tieren wurden mit virulenten und attenuierten StÄmmen von Poliomyelitis immunisiert und die Antikörperbildung gegen N- und H-Antigen beobachtet. In allen Gruppen wurden zuerst H-Antikörper und spÄter N-Antikörper gebildet. Im weiteren Verlauf der Immunisierung nimmt bei Typ I und Typ II die Bildung von N-Antikörpern wesentlich schneller zu, so da\ die N-Titer bald höher sind als die H-Titer. Gleichzeitig reagieren zuerst mehr Versuchstiere mit H-Antikörper-Bildung, wÄhrend spÄter mehr Tiere N-Antikörper bilden.Bei der Immunisierung mit Typ III reagieren mehr Tiere mit Antikörperbildung gegen H als gegen N, gleichzeitig sind die H-Titer wÄhrend des ganzen Verlaufs höher oder ebenso hoch wie die N-Titer. Die Antikörperbildung gegen die ImpfstÄmme entsprach weitgehend dem Verlauf bei den virulenten StÄmmen. Die Reaktion des Organismus auf die Zufuhr von N- und H-Antigen Ändert sich im Laufe der Immunisierung. Die zu einem spÄteren Zeitpunkt vorgenommenen Booster-Injektionen vermögen das initiale übergewicht der H-Antikörper nicht wiederherzustellen, selbst wenn mehr H- als N-Antigen zugeführt wird.
Antibody production versus poliovirus N and H antigen after immunisation of guinea pigs
Summary Seven groups of guinea pigs consisting of 15 animals each were immunized with virulent and attenuated strains of poliomyelitis virus. Subsequently the antibody production versus N and H antigen was studied. The animals of all groups responded primarily by production of H antibodies and later by N antibodies. During the further course of immunization the production of N antibodies was much faster for type I and II, thus anti N titers soon were higher than anti H titers. In addition, more animals responded initially by production of H antibodies, while later on more animals produce N antibodies. During the immunization with type III more animals produced H than N antibodies and H titers were always higher than N titers or equal. Antibody production to vaccination strains corresponded to a far extent to that of virulent strains. Response of the organism changes during the course of immunization. Booster injections given at a later time do not recall the initial peak of H antibodies, even if a greater dose H antigen is given than N.
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