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141.
142.
Dr. Jacques Bitsch 《Cell and tissue research》1981,220(1):99-113
Summary The wall of the receptaculum seminis of Thermobia domestica is composed of numerous glandular units, each with four enveloping cells (denoted 1 to 4) separated by ordinary epithelial cells and associated with a cuticular apparatus. During the moulting periods, which continue to occur in the adult stage, these cells undergo a series of transformations. Just before apolysis there is a dedifferentiation of numerous cytoplasmic organelles, but no mitosis has been observed. When the intima lifts off, the apical system of each glandular unit, i.e. the distal parts of the C2 and C3 cells surrounding the end apparatus, is also eliminated. Then at the apex of each glandular unit, a new ductule is formed in the cavity of which a long ciliary process grows up from cell C1. Finally comes the phase of cuticle formation, i.e., epicuticle for the ductules, epi-and endocuticle for the intima lining the central cavity of the receptaculum. Various cell types participate in secretion of cuticle, the ciliary cells (C1) being responsible for the formation of the porous end apparatus. At ecdysis almost all of the new intima has been secreted and the apical systems are once more differentiated. These transformations are compared with those recently described in other exocrine glands of arthropods, e.g., tegumentary glands and accessory glands of the genital ducts. 相似文献
143.
Various factor affecting NADPH-oxidation by resting human leucocyte granules (LG) at acid pH, have been investigated.It was found that:
- 1) oxidation of NADPH by LG was increasingly inhibited by increased cyanide concentrations in the medium and was abolished by 4 mM cyanide.
- 2) with or without cyanide in the incubation medium, LG omitted, Mn++, in the presence of NADPH induced superoxide anion (O¯2) production, as evidenced by oxygen consumption and H2O2 production, which were abolished (in the absence of cyanide) by cytochrome C (a potent O¯2 scavenger).
- 3) Both NADPH oxidation in the presence of 2 mM cyanide (cyanide-resistant) and in its absence (cyanide-sensitive) by LG occured only in the presence of Mn++, and both were inhibited by superoxide dismutase.
- 4) Cyanide-resistant NADPH oxidation by LG generated H2O2, was inhibited by H2O2 and was not modified by «active catalase. The ratio of cyanide-resistant NADPH oxidation/O2 uptake was 1 up to 1.25 mM NADPH, and increased above this concentration.
- 5) Cyanide-sensitive NADPH oxidation was inhibited by catalase and increased upon addition of H2O2. The ratio of cyanide-sensitive NADPH oxidation/O2 uptake was 2.
144.
Chamla Yves Bilbeissi Catherine Micheau Marguerite Battin Jacques 《Human genetics》1977,38(2):245-248
Summary A new case of partial trisomy 9q was found in a child presenting two de novo aberrations: a deletion of the long arms of 9 and a 9,21 translocation. A tentative cytogenetic explanation is put forward. 相似文献
145.
Mathew A. Vadas Jacques F. A. P. Miller Alison M. Whitelaw Jennifer R. Gamble 《Immunogenetics》1977,4(1):137-153
Identity at the major histocompatibility complex (MHC) was essential for successful transfer of delayed type hypersensitivity (DTH) in mice. The regions of the MHC involved differed according to the antigen used for sensitization. In the case of fowl gamma globulin (FGG), identity atI-A was necessary, whereas with dinitrofluorobenzene (DNFB), identity at theK, I, orD region was sufficient. These different genetic constraints probably reflect differences in the mechanisms by which antigens are presented to T lymphocytes. Cells from sensitized (CBA×C57BL)F1 mice transferred DTH to FGG into parental-strain mice, but transfer was more effective in C57BL than in CBA with the same cell dose. This phenomenon is governed by the MHC, since there was better transfer intoH-2
b
than intoH-2
k
mice, regardless of their backgrounds. It may reflect the activity of an Ir gene-dependent process. Cells of one genotype (e.g., CBA), sensitized in chimeric mice derived from two MHC-incompatible strains (CBAC57BL), transferred DTH to both strains. These results do not support the notion that the genetic constraint observed in DTH transfer may be a result of the necessity for sensitized T and stimulator cells to match an identical MHC-coded cell interaction molecule. Rather, they favor the hypothesis that T cells recognize antigen, not as a naked determinant, but in close association with products of genes of the MHC. 相似文献
146.
Jacques Diezi Pierrette Michoud-Hausel Nicole Nicolas-Buxcel 《The Yale journal of biology and medicine》1978,51(3):265-270
Two to 4 hours after unilateral renal exclusion in rats, urine flow rate from the remaining kidney had increased to twice the control level, whereas the filtration rate remained unchanged. After contralateral nephrectomy, NGFR was similar to that of controls, but fractional water reabsorption along proximal tubules decreased. Protein concentration in efferent arteriolar plasma, and hydrostatic pressure gradient between proximal tubules and peritubular capillaries were similar in experimental and control kidneys. Unilateral renal exclusion was followed by a rapid increase of blood pressure. Prevention of this rise depressed but did not abolish functional compensatory adaptation. The occurrence of compensatory adaptation was not affected by decreased renal perfusion pressure. 相似文献
147.
Dr. Jacques Toupin Donald H. Marks Edwin L. Cooper Gilles Lamoureux 《In vitro cellular & developmental biology. Plant》1977,13(4):218-222
Summary Contamination and low viability of earthworm coelomocytes in tissue culture have delayed in vitro studies. Using penicillin,
streptomycin, tetracycline and Amphotericin B,Lumbricus terrestis coelomocytes were maintained viable and uncontaminated for 10 days at 15°C in medium L-15 supplemented with 5 to 10% fetal
bovine serum. The coelomocytes survived for at least 10 days with 85% viability as assessed by trypan blue exclusion assays
and phagocytosis of heat-killed yeast. Studies on the thymidine uptake, however, were negative. With the involvement of coelomocytes
in tissue graft rejection, in vitro techniques can now be applied to study their capacity in the immune response.
Supported in part by USPHS Research Grant 1 RO 1 HD09333-01 to E. L. Cooper. 相似文献
148.
Alain Rabi Maryse Selme-Matrat Marie-Claude Clavel Jean Clos Jacques Legrand 《Developmental neurobiology》1977,8(4):337-354
Newborn rats were treated at different stages of their development with low doses of methylazoxymethanol acetate. The postnatal increase of the DNA content of the cerebrum did not differ from that of controls. In the cerebellum, the DNA content was transitorily reduced, but later, the external granular layer became thicker and DNA deposition increased in comparison with controls; finally, the cerebellar DNA returned to a normal value. Morphological abnormalities of the cerebellum, abnormal orientation of migrating cells, scattering of Purkinje cell bodies within the internal granule cells and specially striking abnormalities of the morphology and orientation of Purkinje cell dendrites were noted in rats treated with MAM from birth to day 3. The effects on the Purkinje cell morphogenesis persisted but were much less marked when MAM was given from 4 to 7 or from 8 to 11 days. Neonatal thyroid deficiency, as MAM-treatment between days 0 and 3, leads to an abnormal position of Purkinje cell bodies within the cerebellar cortex; it also leads to morphological abnormalities of their dendritic arborization which closely resemble those observed after MAM-treatment during the second postnatal week. It also alters the cell formation in the cerebellum. Thyroid deficiency probably exerts its effect on cell formation earlier than previous biochemical studies have shown. On another hand, the morphological abnormalities of Purkinje cell arborizations in the thyroid-deficient animals may be partly due to the perturbations of cell formation which persist later in the cerebellum. 相似文献
149.
In the fungusPodospora anserina, themodC mutations inhibit the sexual female organ differentiation. Previous results have suggested that the plasma membrane of this mutant may be altered. Proteins solubilized from highly purified plasmalemma from a wild-type and threemodC mutant strains were studied by one- and two-dimensional electrophoresis. Isoelectric focusing revealed in the wild-type strain about 80 polypeptide spots whose molecular weight ranged from 15,000 to 80,000 daltons; 65% of the spots were between 20,000 and 60,000 daltons, and 60% were in the 6.5–7.5 pH zone. The only difference inprotein noted between wild-type and the threemodC mutants was that the threemodC mutants lacked a plasmalemma protein of Mr=42,000 and of pI=6.7. These results suggest a close relationship between plasma membrane proteins and differentiation in this eukaryotic organism. 相似文献
150.