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41.
42.
We surveyed a French male population for the incidence of missing or reduced upper lateral incisors (ULI). In 5,738 subjects, we observed an incidence of 1.59% with one or two reduced ULI (the other normal) and 1.90% with one or two missing ULI (the other normal or reduced), altogether, 3.49% affected subjects. Furthermore, 250 random controls were observed. Agenesis of other teeth is more frequent in propositi. Missing third molars were 12.4% in controls, 24.0% in propositi with reduced ULI and 39.6% in propositi with two missing ULI. Furthermore, agenesis of incisors, canines and premolars ranges from 0.4% in controls to 1.3% in propositi having reduced ULI and 5.0% in propositi with two missing ULI. So, propositi with reduced ULI are intermediate between the controls and the propositi with missing ULI with respect to the frequency of agenesis of other teeth. On the other hand, a different ranking is observed with respect to the teeth measurements: reduction of tooth size is more marked in propositi with reduced ULI than in propositi with missing ULI. The reduction mainly affects canines, incisors and to a lesser degree, premolars. Arch length and interpremolar diameters are smaller in propositi with missing ULI, compared with controls.  相似文献   
43.
In thylakoid membranes, several peptides of high MW are present which may interfere with the study of CP1's components. Modifying Cleveland's technique [7] for limited proteolysis, we have characterized the polypeptides found in the 60 kD region. Some may result from incomplete washing of the CF1 while others come from the CP1; indeed, this chlorophyll protein complex, which has a higher MW (above 100 kD), very often undergoes a dissociation into smaller components of about 60 KD MW.Analysis of the protein content of different preparations commonly used to obtain PSI reaction centre enriched fractions has been performed. The and subunits of CF1 are among the main contaminants of most of these preparations. A further purification step is described which can be applied to all these preparations, but numerous peptides are still present in the active fractions. It is most unlikely that all these polypeptides are required for the primary photochemical event, and this emphasizes the necessity to find a new simple method to purify PSI reaction centres.  相似文献   
44.
A sialyl transferase activity is found in purified mitochondria. It is not due to residual contamination and this enzymatic system is located in the outer mitochondrial membrane. This proves mitochondrial autonomy in regard to glycoconjugate sialylation.  相似文献   
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46.
Summary The mandibular glands of Kalotermes were examined in different castes. They showed sexual dimorphism in the soldiers and primary reproductives. Moreover, in female soldiers and queens, mandibular gland cells contained numerous crystalline structures of mitochondrial origin. The role of these glands (secretion of saliva or pheromone) is discussed.
Résumé Les glandes mandibulaires de Calotermes sont étudiées dans les différentes castes. Elles présentent un dimorphisme sexuel chez les soldats et les sexués. Après la mue imaginale, les cellules glandulaires ont toujours une activité sécrétrice. De plus, chez les soldats femelles et les reines, elles contiennent de nombreuses formations cristallines d'origine mitochondriale. Le rôle de ces glandes (sécrétion de salive ou de phéromone) est discuté.
  相似文献   
47.
Urinary iodine excretion was assessed in 642 healthy children aged 10 mo (n=243), 2 yr (n=183), and 4 yr (n=216) living in the Paris area and originating from continental France (60.3%), North Africa (13.8%), the West Indies (9.1%), West Africa (8.3%), Southeast Asia (4.8%), and southern Europe (3.8%). Mild impairment of neurological (reflexes, tone, audiometry) and intellectual development (Brunet-Lézine scale) was assessed in relation to iodine status. Iodine excretions (median values) were 18.4, 11.9, and 10.9 μg/100 mL at 10 mo, 2 yr, and 4 yr, respectively, and risk of mild iodine deficiency (5–10 μg/100 mL) was 18.1%, 34.8%, and 38.3% for the same age groups. No relationship was found between anthropometry, global development quotient, and iodine status. High hearing thresholds were more commonly associated with lower iodine excretion, suggesting mild hearing defects. In spite of iodine prophylaxis, the risk of mild to moderate iodine deficiency still exists in France and in a number of European countries. Evaluation of neurological sequels of borderline iodine status is a major public health problem in European communities.  相似文献   
48.
(1) Incubation of the beef heart mitochondrial ATPase, F1 with Mg-ATP was required for the binding of the natural inhibitor, IF1, to F1 to form the inactive F1-IF1 complex. When F1 was incubated in the presence of [14C]ATP and MgCl2, about 2 mol 14C-labeled adenine nucleotides were found to bind per mol of F1; the bound 14C-labeled nucleotides consisted of [14C]ADP arising from [14C]ATP hydrolysis and [14C]ATP. The 14C-labeled nucleotide binding was not prevented by IF1. These data are in agreement with the idea that the formation of the F1-IF1 complex requires an appropriate conformation of F1. (2) The 14C-labeled adenine nucleotides bound to F1 following preincubation of F1 with Mg-[14C]ATP could be exchanged with added [3H]ADP or [3H]ATP. No exchange occurred between added [3H]ADP or [3H]ATP and the 14C-labeled adenine nucleotides bound to the F1-IF1 complex. These data suggest that the conformation of F1 in the isolated F1-IF1 complex is further modified in such a way that the bound 14C-labeled nucleotides are no longer available for exchange. (3) 32Pi was able to bind to isolated F1 with a stoichiometry of about 1 mol of Pi per mol of F1 (Penefsky, H.S. (1977) J. Biol. Chem. 252, 2891–2899). There was no binding of 32Pi to the F1-IF1 complex. Thus, not only the nucleotides sites, but also the Pi site, are masked from interaction with external ligands in the isolated F1-IF1 complex.  相似文献   
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50.
Glial fibrillary acidic (GFA) protein has been synthesized in an RNA-dependent cell-free system derived from rabbit reticulocytes. The cell-free synthesized product appears to have the same size as GFA protein isolated from bovine spinal cord, thus showing that GFA protein does not undergo detectable proteolytic processing.  相似文献   
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