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21.
22.
Archambeau JO Mathieu GR Brenneis HJ Thompson KH Fairchild RG 《Radiation research》1968,36(2):299-326
When the skin of the shoulder ("A" field) and lower back ("C" field) is irradiated through 10-cm-diameter fields with 250-kVp x-rays, having a HVL of 0.87 mm copper, a dose range is reached between approximately 1600 rads and 3000 rads in which a moist reaction is or is not formed. If a moist reaction is formed, it either heals completely, partially, or not at all. The evolution, time course, and dose dependence of the moist reaction that occurs following irradiation has been determined. The moist reaction is found at 17.5 +/- 0.6 days in the "A" field, and 20.8 +/-0.8 days in the "C" field. The reaction evolves to involve from 5 % to 100% of the field by 24.9 +/- 0.5 days in the "A" field and by 28.5 +/- 1.0 days in the "C" field. Healing is complete by 36.0 +/-1.0 days in the "A" field and by 38.0 +/- 1.3 days in the "C" field. The area of the field involved with a moist reaction at the time of maximal involvement is dose-dependent. The area of the field involved with a moist reaction at the time of complete healing is also dose-dependent. The dose at which 50 % of the fields were not healed was 2273 +/-103 rads in the "A" field, 2578 +/-141 rads in the "C" fields, and 2437 +/- 89 rads in the "A" and "C" fields. The values in the "C" field are significantly different from those in the "A" field except for the dose at which 50 % of the fields were not healed and the time at which the field was maximally healed. 相似文献
23.
Infection in Mouse Peritoneal Cavity with a Pyrimidine-requiring Mutant and Naturally Occurring Staphylococcus aureus Strains 总被引:1,自引:0,他引:1
The lethal activity of a thymineless mutant of Staphylococcus aureus Wood 46 strain has been compared with that of three naturally occurring strains: parent Wood 46, Smith, and coagulase-negative SA-13. The thymineless mutant and the parent Wood 46 strain showed a sharp decline in culturable units from the peritoneal cavity in the first 4 hr after their injection. After 6 hr, that is, 2 hr before the mice began to die, the number of culturable units of the thymineless mutant was still declining, whereas that of the parent strain increased; for both strains, the number of units was still lower than that of the inoculum. Although the thymineless mutant, unlike the parent strain, was apparently unable to multiply in mouse peritoneal cavity, it killed mice at a similar rate. The highly virulent Smith strain known to multiply rapidly and the avirulent coagulase-negative SA-13 strain were used as additional controls. Under our experimental conditions, death of mice after the injection of the thymineless mutant in the peritoneal cavity did not seem to be due to bacterial multiplication but to toxicity, death being delayed by antitoxin. The pyrimidine-requiring auxotroph we used could be better material than killed bacteria to study some aspects of the lethal activity of S. aureus. 相似文献
24.
Protein kinase NII and the regulation of rDNA transcription in mammalian cells 总被引:12,自引:1,他引:11 下载免费PDF全文
P Belenguer V Baldin C Mathieu H Prats M Bensaid G Bouche F Amalric 《Nucleic acids research》1989,17(16):6625-6636
25.
Dispersed canine antral mucosal cells were prepared by sequential steps of collagenase digestion and EDTA treatment. Cell preparations enriched in gastrin cells were made by centrifugal elutriation followed by step density gradient centrifugation. Specific, saturable, and reversible binding of 125I-[Tyr4]-bombesin was found in all preparations. This saturable binding was time, temperature, and cell number dependent. In both velocity (elutriator) and density cell separation experiments, saturable binding of bombesin correlated with the distribution of cells containing gastrin- but not somatostatin-like immunoreactivity. Maximal specific binding to gastrin (G) cell-enriched fractions was reached in 45 min at 37 degrees C and constituted 90% of total binding. Addition of 100 nM nonradioactive bombesin to cells incubated with 50 pM 125I-[Tyr4]-bombesin for 45 min resulted in time-dependent dissociation of specifically bound tracer to about 40% of the maximal equilibrium binding. Analysis of saturable equilibrium binding yielded a best fit to a one-site model of high affinity binding sites with an apparent Kd of 85 +/- 14 pM and a Bmax of 231,000 +/- 71,000 receptors/gastrin cell. Nonradioactive [Tyr4]-bombesin and related analogs inhibited the specific binding of the tracer in a dose-related manner. The rank order of potency, determined at the IC50, of [Tyr4]-bombesin and related analogs for inhibition of specific binding was bombesin greater than [Tyr4]-bombesin = hGRP-27 greater than GRP-10 greater than ranatensin much greater than neuromedin B. Cholecystokinin, somatostatin, substance K, and kassinin each tested at a concentration of 1 microM did not inhibit bombesin binding.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
26.
Henry M Benlimame N Boucaud-Camou E Mathieu M Donval A Van Wormhoudt A 《Tissue & cell》1993,25(4):537-548
(1) alpha-amylase was extracted and purified from the stomach/digestive gland complex of the scallop Pecten maximus and an anti-serum was induced against the purified amylase by rabbit immunization. (2) The anti scallop amylase was used to localize the amylase-secreting cells in the stomach of Pecten maximus by immunofluorescence and immunogold labelling. The amylase-secreting cells are glandular cells particularly numerous in the main sorting area of the stomach. Their secretory granules were found strongly positive for anti-amylase. Three types of glandular cells were observed, actually corresponding to the three stages of the glandular-cell activity, synthesis, secretion and excretion. (3) The synthesizing cell shows the characteristic features of a protein-synthesizing cell: a conspicuous nucleolus and abundant granular endoplasmic reticulum. In the secretory cell, the secretory granules are formed by the Golgi apparatus and accumulate in the apical part of the cell. The secretory cell is filled with two types of secretory granules which are released in the stomach lumen by apocrine excretion. (4) The present study brings the first demonstration of the synthesis and extracellular release of amylase by glandular cells of the stomach epithelium of a bivalve. 相似文献
27.
D. P. Chora L. Reddy S. K. Gupta L. Wan P. A. Mathieu R. L. Shoemaker J. S. Rhim 《In vitro cellular & developmental biology. Animal》1994,30(8):539-546
Summary Cystic fibrosis (CF) involves abnormalities in mucus production and secretion of the airway. Studies of the regulation of
airway mucin production and secretion has been difficult due to the lack of in vitro models of the airway epithelial cells
which express functional differentiation. Because the majority of the mucin in the airway is apparently produced by the submucosal
glands, we have focused our attention on the development of cell culture models of human airway submucosal glands. This report
describes the propagation of CF airway submucosal gland epithelial cells which continue to express mucin production. The CF
bronchus was obtained from a 31-yr-old patient who received a double lung transplant. The glands were dissected out and primary
cultures prepared by the explant/outgrowth procedure. The cells were immortalized by infection with Adl2-SV40 hybrid virus.
The cultures are maintained in serum-free keratinocyte basal medium supplemented with insulin (5μg/ml), hydrocortisone (0.5μg/ml), epidermal growth factor (10 ng/ml), bovine pituitary extract (25μg/ml), and antibiotics. Cultures were passaged using 0.125% trypsin in Ca+2 and Mg+2-free Hanks’, balanced salt solution. Polymerase chain reaction (PCR) analysis demonstrated that the cells were homozygous
for the ΔF508 mutation. Morphologic observations showed that the cells were epithelial and were interconnected by sparsely
distributed desmosomes. Their cytoplasm contained secretory-type structures including abundant Golgi, rough endoplasmic reticulum,
and secretory vesicles. Immunofluorescent studies determined that all cells were positive for cytokeratins, mucin glycoconjugates,
and cystic fibrosis transmembrane conductance regulator. The cultures secreted substantial amounts of mucin glycoproteins
and expressed the MUC-2 mucin gene. Patch clamp experiments revealed that the cells expressed defective Cl− channels which were not activated by Forskolin. 相似文献
28.
Mesenterocin 52, a bacteriocin produced by Leuconostoc mesenteroides ssp. mesenteroides FR 52 总被引:3,自引:0,他引:3
F. Mathieu I. Sudirman Suwandhi N. Rekhif J.B. Millière G. Lefebvre 《Journal of applied microbiology》1993,74(4):372-379
F. MATHIEU, I.S. SUWANDHI, N. REKHIF, J.B. MILLIERE AND G. LEFEBVRE. 1993. One hundred and sixty-five isolates of Leuconostoc spp. were tested for bacteriocin production. Only one strain, Leuc. mesenteroides ssp. mesenteroides FR 52, isolated from a raw milk, produced a bacteriocin which was named Mesenterocin 52. This bacteriocin inhibited other Leuconostoc strains and several strains of Enterococcus and Listeria spp. No activity was found against lactococci and lactobacilli. The antibacterial spectrum differed from that of previously described Leuconostoc bacteriocins. Mesenterocin 52 was secreted into the medium during the growth phase. It was inactivated with protease treatments. At pH 7.0 it had a relative stability after heating at 100C (15 min), but it had a greater stability at pH 4.5 than at pH 7.0 after 6 h at 80C. The apparent molecular mass was estimated to be less than 10 kDa by ultrafiltration. Mesenterocin 52 showed a bactericidal effect on Leuconostoc paramesenteroides DSM 20288. 相似文献
29.
Marie-Dominique Rhoda-Hardy-Dessources René-Serge de Neef Guy Mérault Françoise Giraud 《生物化学与生物物理学报:疾病的分子基础》1993,1181(1):90-96
PtdIns and PtdInsP kinases from normal erythrocyte (AA) membranes and sickle cell anaemia erythrocyte (SS) membranes have been characterized. PtdIns kinase was studied in native membranes under conditions in which PtdInsP kinase and PtdInsP phosphatase do not express any activity. Kinetic analysis of the AA and SS PtdIns kinases indicate similar Km values for PtdIns and ATP but higher Vmax values for SS PtdIns kinase. PtdInsP kinase was partially purified from erythrocyte ghosts by NaCl extraction. The kinetic parameters of PtdInsP kinase determined under these conditions were similar in AA and SS NaCl extracts. These data suggest the presence of some effector of PtdIns kinase in SS cell membranes, resulting in a greater activity of the enzyme. This leads consequently, to increase the PtdInsP pool and to activate PtdInsP kinase, in agreement with our previous observations of a greater [32P]Pi incorporation in both polyphosphoinositides in SS cells relatively to AA cells. 相似文献
30.
Souad El Hafidi Khadija Bakhy Mohammed Ouhssine Abderrahim Benzakour Hamid Khamar Joseph Casanova Mathieu Paoli Félix Tomi 《化学与生物多样性》2023,20(1):e202201022
Cladanthus scariosus (Ball) Oberpr. & Vogt is endemic to Moroccan High Atlas. It is known under the vernacular names Irezghi or Irezgui. Three essential oil samples have been isolated from aerial parts and analyzed by combination of chromatographic and spectroscopic techniques [gas chromatography (GC) in combination with retention indices (RI), gas chromatography-mass spectrometry (GC/MS) and 13C-NMR spectroscopy]. The compositions of oil samples were dominated by monoterpenes: α-pinene sabinene, and terpinen-4-ol. Chamazulene and dihydrochamazulene isomers as well as various hemiterpene esters and analogs have been identified. To evidence a chemical variability, statistical analysis performed on 13 oil sample compositions allowed partitioning into three groups, mainly differentiated by their contents of sabinene, camphor, borneol, terpinen-4-ol, and germacrene D. 相似文献