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1.
The cytokinin activities of various 6-acylaminopurines, 6-alkylaminopurines, 6-acylamino-9-benzyl-purines as well as a series of isosteric-nitrogen derivatives of N6-(γ, γ-dimethylallyl)adenine (I6Ade) have been tested using the tobacco pith and the pea bud bioassays. The interactions between active, slightly active and inactive compounds have been studied with the last assay. Acylation decreases the biological activity; e.g., N6-benzoyl and N6-furoyladenines are less active than Na6-benzyladenine and kinetin. Substitution at the 9-position reduces (tobacco-pith assay) or suppresses (pea-bud assay) the phytohormonal activity of otherwise active 6-acylaminopurines. In isosteric derivatives, maximum activity occurs when the side chain has the same length as in 16Ade. After the analysis of interactions between more or less active compounds, it is suggested that the differences in cytokinin activity could be related to unequal affinities for a hypothetical receptor site.  相似文献   

2.
From the Aptian scolecodonts inventory of the Agadir area one jaw apparatus and one joining of polychetes are reconstructed. One is the elementary species Schistomeringos expectatusSzaniawski & Gazdzicki, 1978, the oldest representative of the multielementary family Dorvilleidae Chamberlin 1919. The other is a representative of either the multielementary families Atraktoprionidae Kielan Jaworowska 1966 emend. Kozur, 1970 or Arabellidae Hartman 1944. This joining is considered as an hypothesis since all the necessary criteria, defined by H. Szaniawski & A. Gazdzicki 1978, are not all present.  相似文献   

3.
The development of phylogenetic methods since the beginning of the 1970s is analyzed through Armand de Ricqlès’ comment, in 1975, on the triumph of the spirit of geometry over the spirit of finesse. Cladistics was then compared to geometry (Hennig's congruence [i.e. congruent character-state trees]). However, the qualitative aspect of anatomy (spirit of finesse) warrants the quality of a taxon × character matrix so that minimal length trees were never devoid of finesse. Statistical approaches, especially maximum likelihood and Bayesian methods, with sophisticated mathematics (more rigorous geometry?), have reached a wide acceptance after years of debates hindered by polemics. The molecular trees based on these approaches are now dominating the phylogenetic literature, although these trees too include some ambiguity so that one can wonder: do evolutionary models belong to geometry or finesse?  相似文献   

4.
《L'Anthropologie》2022,126(5):103074
The contribution of geology and geomorphology to architectural and technological study of the Atlantic coast of France megaliths is important and can be grouped into three main axes: to identify, interpret and dating. Identification refers to the sourcing of the megalithic materiel from 0 to 7 km, sometimes around 10 km, or even exceptionally around 30 km. It is never the entire supply that is affected by such long distances but only a few blocks, some of them are remarkably well staged in the megalithic architecture. Another contribution lies in a fresh look at the management of stone recognized through the modes of acquisition, transformation and use of the raw material. More particularly, the geomorphology associated with technological reading offers tools for recognizing ancient standing stones. In the context of the interpretation of funerary chambers, the two sciences open a large window on the modalities of the internal structuring of monuments. From the entrance to the end of the chamber, the organization and use of the space is documented, sometimes a symbolic coding emerges from the mineral walls. This symbolic coding is based on particular petrography, on surface conditions operating a subdivision of space, on granulometries and homogeneities of differentiated surfaces. The internal organization can also be marked with natural “patterns”, which refer to a completely new aspect of Neolithic thought. Finally, the last axis concerns relative dating, by recognizing forms of postmegalithic fossil erosion, geomorphology makes it possible to identify reused stelae. A very important tool in a current research context where an important episode of reuse of standing stones at the end of the middle Neolithic is anticipated in the construction of dolmens in the south of France.  相似文献   

5.
Tomato alcohol dehydrogenase has been purified 99-fold by affinity chromatography on Blue Sepharose CL-6B with 37% yield. The enzyme so obtained is homogenous in polyacrylamide gel electrophoresis. By adding 20% glycerol to the extraction and purification buffers, an enzyme is obtained which is stable for several months at 4°. The molecular weight values determined by gel filtration (Sephadex G 200) and polyacrylamide gradient gel electrophoresis on one hand and by polyacrylamide gel electrophoresis in sodium dodecyl sulfate on the other, show that the enzyme exists in dimeric form.  相似文献   

6.
The first tetrapod Vertebrate track discovered in the late Kimmeridgian lithographic limestones of Cerin (Ain-France), is descrbed as a new ichnospecies, named Chelonichnium cerinense. The characteristics of the track, which is about 7 m long, suggest that it was made by a large Chelonian, but none of the fossil turtles known so far from Cerin is likely to be the author of these footprints. The ground on which the animal walked was apparently very wet, superficially soft, and sloping. Moreover, this track is associated to soft sediment slides, confirming emersion and slope. The depositional environment is interpreted as a platform located behind a «ribbon of islands. This irregular surface was at times emerged and terrestrial tetrapods could then leave tracks on the superficial layer.  相似文献   

7.
8.
The discovery of Foraminifera and Ostracodesin the dark green, sandy-glauconitic marl clay in the Joux Valley (in the Vaudois Jura) suggests to date these sediments Middle and Upper Albian. The Ostracode associations are similar to those found in the Paris Basin, but different from those which characterize the subalpine region.  相似文献   

9.
Bernard Courtinat 《Geobios》1980,13(2):209-229
Palynological inventory of Saint-Fromont pit 0815 (Manche, France) related to Hettangian seems to show the conspecificity of Classopollis chateaunoviReyre, 1970, Classopollis kieseriReyre, 1970 and Classopollis harisiiMuir & Van Konijnenburg-Van Cittert, 1970. SEM pictures exibit some sculptural elements interpreted as structural attachments of grains in tetrad and compared to those of genus DicheiropollisTrevisan, 1971.  相似文献   

10.
《Médecine Nucléaire》2014,38(6):449-455
Nuclear imaging techniques have been occupying an increasingly large place in the study of potentially cancerous morphological abnormalities. A National French survey was conducted among members of the French Society of Nuclear Medicine (Société française de médecine nucléaire) to study the usual practices of nuclear medicine physicians regarding information and communication during the “pre-announcement” stage of a cancer diagnosis. Sixty-six doctors (with an average of 44.7 years of age and 16.3 years of experience) working in mainland France responded to the online survey between November 2013 and February 2014. Most physicians said that they were uncomfortable in this kind of situation. Half of the doctors interviewed faced that situation at least 5 times a month. Communication habits were varied: 20% of them adopted a systematic approach (chose ‘always’ or ‘never’ to communicate information regardless of the patients’ demands) and 80% adapted their approach to the situations and to the patients (communication ‘on case by case basis’ and ‘upon request’). The survey also showed that professionals have contrasting views on the relevance, interest and risks of informing patients about the results of the tests in this kind of situation. Our study shows that it is necessary to discuss the position of nuclear medicine physicians in the pre-announcement procedure set out in the French Cancer Plan so as to reduce the challenges facing them while at the same time organizing and defining their roles.  相似文献   

11.
《L'Anthropologie》2016,120(5):537-567
El Cierro Cave (Ribadesella, Asturias, Spain), located near the mouth of the River Sella, has yielded one of the most important Upper Palaeolithic sequences in northern Spain. To date, three major occupation periods at the cave have been identified and dated. The first was at the beginning of the Holocene (ca. 8500 BP; ca. 9000 cal BP); the second at the end of the Upper Palaeolithic, in the Younger Dryas (YD) or Greenland Stadial 1 (GS1) (ca. 11.200 BP; 12.700 cal BP) and the third during Greenland Stadial 2 (GS2) (ca. 16.300–15.500 BP; ca. 19.200–18.700 cal BP). This paper describes the stratigraphy documented in the excavations performed by F. Jordá Cerdá and A. Gómez-Fuentes between 1977 and 1979 and presents the first radiocarbon determinations for the first two occupation periods, together with the study of the archaeological materials found in Level F. This level, dated to 15.500 BP (ca. 18.700 cal BP) is characterised by specialised red deer hunting and the gathering of marine resources (winkles). Various artefacts made from animal raw materials have been documented; both finished products and items in the process of being manufactured, as well as portable art objects. The lithic assemblage, consisting mainly of local raw materials with a small proportion of allochthonous flint, is characterised by an abundance of small bladelet cores and backed bladelets. These archaeological remains and the radiocarbon date mean Level F can be attributed to the so-called “Cantabrian Lower Magdalenian”. This period has been documented archaeologically and dated to a similar time at other sites in the River Sella valley and in the rest of northern Spain.  相似文献   

12.
13.
Ecdysterone acts differently according to the period of the moulting cycle when it is applied. In period C it induces apolysis, while at the beginning of apolysis it delays ecdysis. Experiments show that the exoskeleton cannot be rejected in the presence of ecdysterone. The possibility of stopping exuviation or ecdysis with ecdysterone seems to prove that this phenomenon is controlled by a particular factor called the factor of exuviation or the ecdysis factor. Ecdysterone would control only the release of this specific factor but would not prevent its action.  相似文献   

14.
Annick Isaia 《Planta》1971,96(2):175-182
Summary The activities of (±)-abscisic acid and a number of compounds derived from p-coumaric acid and coumarin and their interaction with gibberellic acid in the control of the elongation of the first wheat leaf are examined. (±)-Abscisic acid strongly inhibits leaf growth in the presence as well as in the absence of gibberellic acid, but the inhibition is greater in the presence of gibberellic acid (3 g/l already have an observable effect). Among other compounds, only ferulic acid and coumarin significantly reduce leaf elongation, and they are effective only at high concentrations (1.44 · 10-4 M/l).  相似文献   

15.
《Médecine Nucléaire》2020,44(1):12-17
IntroductionMetastatic differentiated thyroid carcinoma (MDT) represents an average of 10% of patients with CDT. Metastases are prognostic factors. Their care is multidisciplinary.ObjectiveTo study the epidemiological, clinical, histological, therapeutic and evolutionary aspects of metastatic CDT and to study the impact of new recommendations.Patients and methodsRetrospective study of 70 patients followed for a metastatic CDT collected between June 2007 and June 2017, in the nuclear medicine department of Hassan II University Hospital of Fez.ResultsMean age 51.34 ± 15.96 years, sex ratio F:H: 2.5. Age > 45 years old at 65.7% of whom 42.8% > 55 years old. Circumstances of discovery: nodule 15.8%, multi-hetero-nodular goiter 17.1%, metastases 65.7%. Multivariate analysis shows a significant correlation of age greater than 45 years (P: 0,001) and revealing metastasis. Histology: papillary carcinoma 72.9%, vesicular carcinoma 22.8% and carcinoma poorly differentiated 4.3%. Tumor > 4 cm in 45.7%, the TNM classification (2010) vs. TNM classification (2017): 31.4% vs. 48.6% in stage I, 12.9% vs. 28.6% in stage II, the stage III in 17.1% vs. 0% and 38.6% vs. 22.8% in stage IV. Complementary investigations: localization of metastases: 40% at the bone level, 31.4% lung, 14.3% ganglionnaires and others 9.9%. Hormonal braking treatment was administered in all patients and the « irathérapie » (ATA vs. French recommendation 2017).EvolutionSeven cases of cure, 1 case of recurrence, 4.3% refractory to iodine.ConclusionThe presence of metastases, worsens the prognosis. Therapeutic de-escalation with French recommendations. Bone localization was predominant, its management is multidisciplinary, and radioactive iodine as a complementary treatment does not allow their healing.  相似文献   

16.
Two computation methods are explained; theirobject is the estimation of the velocity of animals which are known by their footprints, and in the case of the first method, by their skeletons as well.The first method is based on the compound pendulum theory, because during the slow walking gait, the motion of the leg is similar to the oscillation of a pendulum, for the computation of the velocity (v), are considered: moment of inertia (I), radius of gyration (P) and period (T), time in seconds to cover one stride (E) in the case the maximum angle of divarication (δ) of the leg with the vertical is ≤20°. A comparison with the formula of Alexander (1976) is discussed.The second method concerns saltator animals. It is based on the fondamental laws of dynamics. With the length of the jump (E) it is possible to estimate the velocity of the trackmaker (v) and the height of the jump (K). For the vertebrates the angle of the trajectory with the horizontal plan (α) is between 20 and 45°. Thus, the result of this method is an interval of estimation in which the velocity is included.These methods do not give precise results. But these approximations supply valid informations on the velocity of extinct or living animals and can lead to the estimation of their maximum speed if the parameters E, T, vary. The problem of the errors is also discussed. It is shown that the errors in estimating the parameters have a no significant influence on the results.  相似文献   

17.
We report on the case of a man with a previous history of testicular seminoma and a pathological paravertebral mass definitely taking-up FDG on PET/CT. This mass was finally a benign schwannoma.  相似文献   

18.
Diabetes is an important risk factor of myocardial ischemia. Myocardial perfusion imaging (MPI) is used for diagnostic, prognostic assessment and for post-therapeutic follow-up of coronary artery disease (CAD). Its usefulness has been documented extensively in the general population. However, in diabetic population, little studies have been published. CAD is more severe and more frequent among diabetic patients. The goal of this work was to assess usefulness of MPI among diabetic patients. This work includes 44 diabetic patients (22 women, 22 men), investigated by stress MPI in nuclear medicine department of Ibn Rochd UH of Casablanca. The studied parameters concerned: age, antecedents of CAD, risk factors of CAD associated to diabetes, duration of the diabetes, diabetes complications, diabetes treatment, indication of MPI, presence or not of anomaly on the ECG performed at rest, existence or not of typical or atypical clinical signs of CAD, investigations and therapy prescribed as well as the occurrence or not of cardiac event during monitoring after MPI. Results of MPI have been compared to clinical, therapeutic and monitoring data of patients. Mean age of patients was 55 years (39 to 75 years), mean diabetes duration was 8.6 years (1 to 30 years), at least one diabetes complication has been noted in 18 patients. The most frequent complication was diabetic retinopathy. MPI has been achieved for diagnosis of ischemia in 37 patients and assessment of anti-ischemic treatment in 7 cases. Treadmill exercise has been achieved in 34 cases and a pharmacological stress in 10 others. During follow-up, which was between 1 and 36 months (mean: 14.9 months), 6 cardiac events occurred among the 44 patients. Patients with abnormal findings at stress MPI had two cardiovascular risk factors or more associated to diabetes (91.3% vs. 9.5% among patients having normal findings, P < 0.001) and had diabetic retinopathy more often (56.5% vs. 9.5% among patients with normal findings, P < 0.001). Cardiac events were more frequent among men (100% vs. 43.2% of patients who did not have a coronary event, P < 0.01). Patients with stress MPI showing ischemia in 3/17 segments or more have presented a cardiac event more often during the follow-up (4/12 Vs 2/32 among patients with normal MPI or defect in less than 3/17 segments, P < 0.01). In this series, coronary artery disease was found more frequently among patients having more than 2 cardiovascular risk factors. In addition, risk of cardiac event seems related to extent of uptake decrease.  相似文献   

19.
Christian Gaillard 《Geobios》1978,11(4):439-455
Coprulus, described by R. Richter & E. Richter (1939a) is very abundant in the Oxfordian marls and muddy limestones of the French Jura Mountains. These small cylindrical calcareous bodies are characterised by longitudinal grooves. They have been often found in washings but are also visible in thin sections. Coprulus is rarely mentioned by micropaleontologists but its stratigraphical and geographical range is certainly very extended. Often considered as Problematica, this trace fossil has been differently interpreted. This work confirms and specifies the results of F. Gramann (1966): Coprulus represents a fecal pellet of a deposit-feeder mollusc (Nuculidae?). Three new ichnospecies are described herein and the ichnogenus Coprulus is compared with Bactryllium, Coptocampylodon and Tomaculum.  相似文献   

20.
Résumé Dans l'épithélium intestinal de la larve du discoglosse, nous avons recherché par le microscope électronique les activités de trois enzymes lysosomiques: la phosphatase acide, la thiolacétate-estérase et l'aryl sulfatase.Avant le climax de la métamorphose, l'activité phosphatasique acide se localise dans des corps au diamètre inférieur au micron, présents dans la zone supranucléaire de l'épithélium primaire. Durant la période climacique (émergence du premier membre antérieur), le produit de réaction diffuse depuis ces lysosomes et occupe le hyaloplasme environnant. Des aires d'autolyse aux limites imprécises apparaissent alors dans l'épithélium. A leur voisinage, on reconnaît de nombreuses vacuoles autolytiques, aux dimensions variées et en général phosphatase acide-positives; elles sont accompagnées de leurs formes d'évolution (corps résiduels) enrichis en tourbillons membranaires; les plus grandes de ces vacuoles pourraient naître après encerclement des aires d'autolyse diffuse. En fin de climax, le phosphate de plomb envahit tout le hyaloplasme, cependant que des fragments cellulaires dégénérés se remarquent dans la lumière de l'organe. Au contraire, l'épithélium secondaire de remplacement est toujours dépourvu du produit de réaction.La mise en évidence des activités thiolacétate-estérasique et aryl sulfatasique confirme la nature lysosomique des corps supranucléaires et des vacuoles autolytiques de l'épithélium primaire.
Histochemical study of some lysosomal hydrolases of the intestinal epithelium during the development of the tadpole of Discoglossus pictus otth, anuran amphibianII. Observation with the electron microscope
Summary In the intestinal epithelium of the tadpole of the discoglosse, we have analysed the activities of three lysosomal enzymes: acid phosphatase, thiolacetate-esterase and arylsulphatase with the electron microscope.Before the climax of the metamorphosis, the acid phosphatase activity is localized in bodies smaller to one micron in diameter, which are observed in the primary epithelium supranuclear cytoplasm. During the climax (emergence of the first fore-leg), the reaction product diffuses itself from these lysosomes and occupies the surrounding hyaloplasm. Then, autolytic unprecise-limited areas appear in the epithelium. In their neighbourhood, many, more or less large and acid phosphatase-positive, autolytic vacuoles are recognized; they are surrounded by their residual bodies enriched with membrane whorls; the larger vacuoles might appear after segregation of diffuse autolytic areas. At the end of the climax, the lead phosphate invades the whole hyaloplasm; in the meanwhile, cellular degenerated bits are to be seen in the intestinal lumen. On the contrary, the secondary epithelium replacing the primary is always devoid of the reaction product.The visualization of the activities of thiolacetate-esterase and arysulphatase confirms the lysosomal nature of the supranuclear bodies and the autolytic vacuoles of the primary epithelium.
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