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1.
A 14-days' training of rats designed to adapt the animals to the procedure of blood-pressure measurement caused in the myocardium a decrease, in serum an increase in noradrenaline ( NA) content. The latter remained unchanged following 3 days of treatment with 2.5 mg depot angiotensin II (AII) but decreased by more than one-half in the myocardium of untreated animals, and increased in serum. Despite the considerable difference in myocardial NA content and blood-pressure behaviour, both trained and untrained rats showed the same morphological reactions following administration of A II. These myocardial alterations which largely correspond to the so-called epinephrine myocarditis should not therefore be due solely to NA action; rather, the involvement of A II should be considered also.  相似文献   
2.
The total population affected with non-Hodgkin's lymphoma and treated by means of radiotherapy or combined radio-chemotherapy between 1960 and 1985 at the Medical Academy Dresden was analysed as to prognosis. 247 patients were classified according to the previous German scheme, 79 were subdivided on the basis of the recommendations laid down in the Kiel classification. The remission rates and survival curves achieved will stand out the comparison with international literature (remission rates of the low malignancy group amounted to 85.3 p.c. and those of the high malignancy group to 80.0 p.c.; the 5-years survival rates of the low malignancy group amounted to 61.9 p.c. and those of the high malignancy group to 41.7 p.c.). The influence of histology, clinical stage and involvement of organs is discussed on the basis of our results and informations obtained in literature. Our analysis confirms the high importance which must be attached to a common radiologic-internal outpatient-department for co-ordinating the diagnostic and therapeutical programme.  相似文献   
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The colonies of thecate hydroids are covered with a chitinous tubelike outer skeleton, the perisarc. The perisarc shows a species-specific pattern of annuli, curvatures, and smooth parts. This pattern is exclusively formed at the growing tips at which the soft perisarc material is expelled by the underlying epithelium. Just behind the apex of the tip, this material hardens. We treated growing cultures of Laomedea flexuosa with substances we suspected would interfere with the hardening of the perisarc (L-cysteine, phenylthiourea) and those we expected would stimulate it (dopamine, N-acetyldopamine). We found that the former caused a widening of and the latter a reduction in the diameter of the perisarc tube. At the same time, the length of the structure elements changed so that the volume remained almost constant. We propose that normal development involves a spatial and temporal regulation of the hardening process. When the hardening occurs close to the apex, the diameter of the tube decreases. When it takes place farther from the apex, the innate tendency of the tip tissue to expand causes a widening of the skeleton tube. An oscillation of the position at which hardening takes place causes the formation of annuli.  相似文献   
6.
We have investigated by electron spin resonance, at 37 degrees C, the outside-inside passage and the equilibrium distribution of spin-labeled phospholipids, respectively, in ATP-containing ghosts, in heat-treated erythrocytes, and in heat-induced vesicles. The heat-treated vesicles were spectrin depleted to approximately 25% of the original content and had lost almost 100% of the other cytoskeletal proteins. Yet the vesicles, as long as they contained ATP, were capable of translocating the aminophospholipids with the same efficiency as the heat-treated erythrocytes, and almost with the same efficiency as ATP-containing ghosts. In the vesicles, sphingomyelin and phosphatidylcholine analogues underwent a very slow transverse diffusion as in native cells. We conclude that spectrin and other cytoskeleton proteins are not major factors for the establishment and maintenance of phospholipid asymmetry in human erythrocytes, which may be chiefly due to the aminophospholipid translocase activity.  相似文献   
7.
Various monoclonal antibodies (mAbs) detecting certain different epitopes on myeloid cells (VIMD5, D5 D6, OKM1, Leu-M3, VIEG4, OKIa 1) have been used in combination with conventional markers (antihuman myeloid hetero-antiserum, FcIgG-receptors, C3d-receptors) to further define the phenotypic heterogeneity of myeloid leukemia. Subsequent leukemic samples from previously untreated patients with acute myeloid leukemia (AML) (51 adults, 24 children) and from nine adult patients in the acute phase of chronic myeloid leukemia (CML-BC) were studied. It was possible to demonstrate quantitative differences in the expression of antigens on the various leukemia subtypes which could be exploited for diagnosis. Furthermore our results revealed that there is a very close correlation between the different surface phenotypes and the types morphologically assessed according to FAB-criteria.  相似文献   
8.
Methods for Detecting Food-borne Enteroviruses   总被引:7,自引:7,他引:0       下载免费PDF全文
A method previously reported for detecting virus in a model system composed of cottage cheese contaminated with coxsackievirus type A9 has been adapted to detecting selected strains of enteroviruses in a variety of foods. Bentonite is omitted and serum is added for extracting virus from low-protein foods. Samples of foods, usually 25 g, must contain at least 3 to 4 plaque-forming units for a 50% probability of detecting virus. Sensitivity in detecting echovirus type 6 was lower than that for the other viruses used. After extraction from potato salad, poliovirus type 2 was completely reactivated if it had been neutralized with coproantibody, but it was only partially reactivated if neutralized with hyperimmune rabbit serum.  相似文献   
9.
Der Einfluß des Zeugungsalters auf die Mutationen zu Hämophilie A   总被引:1,自引:0,他引:1  
Assuming that in sibships with sporadic hemophilia the mothers of the patients are already carriers the relationship between the age of the mother's father at birth of the mother and frequency of hemophilia among his grandsons was examined.The ages of the mother's father at birth of the mother of 40 patients with sporadic hemophilia A was compared with that of a control-group as well as with the ages of the mother's fathers at birth of the mothers of patients from families where hemophilia A is inherited. The mean age of these grandfathers was found to be increased. Using the Mann-Whitney-U-test for comparing the ages of grandfathers of sporadic cases with the control-group there is to be found P=.0025, which is highly significant statistically. Comparing data from sibships with sporadic hemophilia with data from sibships where hemophilia is inherited there is no significant difference — perhaps according to the small number of inherited cases (19, P=0.065) —, but the deviation is in the same direction. Comparison of data both from the inherited cases and the control-group with data of sporadic cases gives P=.0087.There is perhaps a connection between parental age and number of children, but it is shown to have no important influence in our material. On the other hand fathers with a higher number of children are significant more frequent among the grandfathers than among the controls. This difference cannot be explained sufficiently. Between cases of sporadic and inherited hemophilia there is no clear cut difference.Certainly there exists a relationship between parental age and birth-rank. Therefore the mothers of sporadic cases — unlike to carriers of sibships with inherited hemophilia — take clearly higher ranks in birth-order than it is theoretically to be expected. Penrose published a method of separating the relative aetiological effects of birth-order and parental age. Using this method an influence of birth-order cannot be found after excluding the influence of parental age. Hence, paternal age seems to be the determining factor.It is discussed which model of mutation the hemophilia-mutation belongs to because of this relationship. We would count it to No. 2 of the classification given by Vogel where mutations are due to copy errors. So cases of sporadic hemophilia seem equal to those of sporadic achondroplasia.

Diese Arbeit wurde der Medizinischen Fakultät der Universität Hamburg als Inaugural-dissertation vorgelegt.

Herrn Prof. Dr. F. Vogel danke ich für wertvolle Hinweise, insbesondere zur statistischen Methodik.  相似文献   
10.
Zusammenfassung An männlichen weißen Ratten wurde das Verhalten des Enzymmusters der Leber 72 Std nach Verbrühung untersucht. Es fanden sich Veränderungen im Sinne einer Aktivitätsverminderung bei der NAD-Cytochrom-c-Reduktase, Isocitronensäuredehydrogenase, ATPase und den PJS-positiven Substanzen. Eine Zunahme der Aktivität wurde bei der alkalischen Phosphatase und einigen Esterasen beobachtet, ebenso traten auch die scharlachrotfärbbaren Substanzen auf. Uneinheitliche Reaktionen zeigten die Succinodehydrogenase sowie die Leucinaminopeptidase, unverändert blieben Glukose-6-phosphat-dehydrogenase, -Glucuronidase, saure Phosphatase, die o-Diacetylbenzol- und die DDD-Reaktion.  相似文献   
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