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1.
An immunofluorescent study of hemopoietic organs in xenogenic (mouse-rat) radiation chimaeras has been carried out by means of specific antiserum against hemopoietic cells of the rat bone marrow. The presence of donor cells was tested at different times after the transplantation in the bone marrow, spleen, lymph nodes, thymus and liver of radiochimaeras. The transplanted cells were shown to populate all hemopoietic organs of the recipient, first of all tissues of the bone marrow type and, then, lymphoid organs. The donor (bone marrow) origin of the extramedullar foci of hemopoiesis in the liver was established.  相似文献   

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Injection of various doses of cisplatin to 2-14-day chick embryos showed that within 2-8 days of incubation cisplatin produces total toxic effect, the number of dead embryos being dependent on a dose of the drug. Within 9-16 days of incubation, i.e. a period when both the mature mesonephros and the developing metanephros are in action, no significant changes were observed in the content of urea and uric acid, the weight of the meso- and metanephros, their water content, and ion content of the blood. Electron microscopic studies revealed no structural changes in the renal tubules. The data obtained suggest that cisplatin does not produce any nephrotoxic effect in chick embryos irrespectively of their age.  相似文献   

3.
Preliminary report on a morphometric study of the neuroepithelium of 1 S and 7 S -- stage chick embryos. We show first that the nucleo-cytoplasmic ratio and then, that the volume fraction of intercellular spaces, nuclei and cytoplasm as they relate to the neural tube, differ significatively from cephalic to caudal portion of the neural tube. At stage 7 S only the volume fraction of intercellular spaces, nuclei and cytoplasm in the neural tube change along the cephalo-caudal axis of the embryos. Finally, between the two stages, at the back of the head, 1) volume fraction of intercellular spaces in the neural tube remains unchanged 2) nucleo-cytoplasmic ratio increase 3) volumetric density and size of mitochondria do not change, while surface density of endoplasmic reticulum in cytoplasm increases.  相似文献   

4.
Studies of the growth-inhibitory action of cortisone on chick embryos   总被引:1,自引:0,他引:1  
A Badran  D V Provenza 《Teratology》1969,2(3):221-233
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5.
The effect of hyperthermia on hemopoietic progenitor cells of the mouse   总被引:1,自引:0,他引:1  
We have studied the effect of heat on four lineage-specific clonogenic cells from mouse bone marrow. The thermal sensitivities of two red cell precursors, one primitive (BFU-E) and one more differentiated (CFU-E), a granulocyte-macrophage precursor (CFU-GM), and a megakaryocyte precursor (CFU-M) were determined after exposure to 42, 43, and 44 degrees C. We found that the erythroid precursors were much more heat sensitive than either the CFU-GM or CFU-M. At 42 degrees C the CFU-E and BFU-E had a D0 of about 30 min, while the CFU-GM and CFU-M had D0 values of about 60 min. Thus the four progenitors could be divided into two distinct classes with respect to their sensitivity to hyperthermia. These results suggest that erythropoiesis is more likely to be suppressed than either thrombopoiesis or leukocyte production when hyperthermia is applied in a clinical setting.  相似文献   

6.
Congenital anomalies on some viscera like heart, liver and kidney have been investigated in chick embryos after a single injection of dilantin (3 mg/egg), a known antiepileptic drug, on 4th day of incubation. On 19th day of incubation, chick embryos were collected to observe the gross malformations and histological changes in heart, liver and kidney. On gross examination, visceroptosis (29%), thin anterior abdominal wall (28%), ectopia cordis (10%) and dextrocardia (1%) were observed. Histological examination of the kidney revealed glomerular degeneration in kidney while in liver, dilated central veins with degenerated hepatocytes were present. Longitudinal section of the heart showed thicker musculature specially of ventricles with a narrower lumen in comparison to that of the control. The results indicate teratogenicity of dilantin in developing chick embryos.  相似文献   

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The influence of B-lymphocytes from various sources on splenic colony formation was studied in the syngeneic system. B-lymphocytes were obtained by panning with IgG-fraction of rabbit anti-mouse Ig, absorbed on Petri dishes. In addition, adherent cells, Thy-1+ and SC-1+ were eliminated from the fraction of Ig(+)-cells. SC-1- and SC-1+ fractions, containing, respectively, stem cells and T-lymphocyte precursors, were obtained by panning with IgG-fraction of rabbit anti-SC-1 serum. SC-1- cells transferred to irradiated syngeneic mice did not induce colony formation in the spleen. Introduction of SC-1- and SC-1+ cells induced formation of colonies. A similar helper effect occurred when SC-1(-)-cells were introduced with bone marrow or lymph node B-cells, but not with splenic B-cells. Splenic, but not bone marrow and lymph node B-cells inhibited colony formation by combination of SC-1- and SC-1+ cells. All effects of Ig+ cells were abolished by treatment of cells with rabbit anti-MBLA serum. Thus, B-cells of various origin can either enhance or inhibit colony formation. The enhancing of inhibitory effect after B (MBLA+)-cells elimination from suspension of bone marrow and lymph node (but not spleen) Ig(+)-cells resulted from the activity of B-contrasuppressors.  相似文献   

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Effects of okadaic acid, a potent non-12-O-tetradecanoyl-phorbol-13-acetate(TPA)-type tumor promoter, on mouse hemopoietic cells were investigated. Okadaic acid stimulated mouse bone marrow cells to form granulocyte-macrophage colony-forming unit (CFU-GM) colonies without added colony stimulating factors(CSFs). At the concentration of 1.82 x 10(-8) M, colony formation of 77 +/- 14 colonies/1 x 10(5) bone marrow cells was observed. Observations on the effects of other cells on the CSF induction suggested that okadaic acid primarily stimulated the functions of macrophages, and the CSF production from macrophages might be attributed to the CFU-GM colony formation. On the other hand, the erythroid colony-forming unit(CFU-E) colony formation stimulated by  相似文献   

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Observation of the cytogenesis of adipose tissue of the chick embryo revealed a quantity of multiversicular structures (MVs) which were found in the intercellular space. Some of them were attached to the adipocytes and others were independently located in the intercellular space. The origin of those MVs appeared to be part of the degenerating mitochondria. Centrally located vesicles and vacuoles in degenerating mitochondria formed a group of short tubules and vacuoles which protruded through the cytoplasmic membrane or bulged out at the edge of the cytoplasmic process. The MVs then spread over the cytoplasmic membrane and finally were discharged from the cell surface as in the manner of apocrine secretion. An invisible barrier between the mass of vesicles and the rest of the cytoplasmic structures appeared to segregate the extruding MVs from the intercellular components such as ribosomes, microtubules, and microfilaments.  相似文献   

15.
B F Schneider  S Norton 《Teratology》1979,19(3):273-278
Data for estimating equivalent ages of rat, mouse and chick embryos are presented, using several sources from the literature. When the time of development of various embryonic structures is matched for the three species, the differences in time for the stages are primarily due to delays in development of the preimplantation blastulas of the rat and mouse in comparison with the incubated chick egg. Development from the blastula stage to completion of major organogenesis proceeds at approximately the same rate for all three species.  相似文献   

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In 10-, 14-and 18-days-old chick embryos, concentrations of total protein and nucleic acids (NA) were measured using spectrophotometry in liver, brain, red gastrocnemial and white pectoral muscles and in chorioallantois. It was shown that the initial protein and NA concentration was the highest in liver and decreased markedly in the above-mentioned organs. At the second half of embryogenesis, concentration of organ protein increased 4 times in muscles, 2 times in brain, and 1.4 times in liver. This indicates a rise of cell density in the organs or of the intracellular protein concentration. The protein/NA ratio reflecting the cell size or concentration of their protein practically did not change in liver, but increased 2.3 and 2.5 times in pectoral and gastrocnemial muscles, respectively, and 2 times in brain. In chorioallantois the maximal protein concentration was observed in then 14-day old embryos, with the protein/NA ratio remaining practically unchanged.  相似文献   

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We studied the effects of three inhibitors of catecholamine synthesis on the development of sea urchins Sphaerechinus granularis and Paracentrotus lividus. These drugs affected the early embryogenesis, which was expressed in inhibition of the cleavage divisions, appearance of abnormal embryos, and developmental arrest. The addition of arachidonic acid amide and dopamine to the incubation medium weakened the effects of the inhibitors. Spiperone induced developmental defects in preimplantation mouse embryos and sea urchin embryos. Arachidonic acid amide with dopamine exerted a protective effect against spiperone when introduced to sea urchin embryos at the blastula or late gastrula stages, rather than after fertilization. In murine embryos, this amide induced developmental defects and arrest itself and its effect was reversible. Possible mechanisms underlying the effects of these drugs are discussed.  相似文献   

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