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1.
Résumé Les acides humiques extraits de 3 sols différents sont étudiés par chromatographie sur colonnes de gel de dextrane Sephadex, successivement sur G 25 F, G 75, G 200.Dans les conditions de l'expérience, on a mis en évidence l'existence de volumes moléculaires privilégiés, et on a pu apprécier les poids moléculaires correspondant à certains d'entre eux.De plus, on n'observe pas de différence qualitative entre les fractions des divers échantillons, mais seulement des variations quantitatives quant à l'importance de ces fractions.  相似文献   

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De eso que llaman Antropología Mexicana (of that known as Mexican Anthropology) first appeared in 1969 in Mexico at critical national and international conjunctures in an effort to both take the pulse of Mexican anthropology and move the discipline in new directions. As the text approaches its 50th anniversary, Dialectical Anthropology organized a forum, soliciting six critical evaluations of the book’s historical role.  相似文献   

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J. P. Hebrard 《Plant Ecology》1973,27(4-6):347-381
Resume Dans le présent travail, l'auteur effectue une étude bryosociologique de la strate muscinale des rochers et des marécages de l'étage subalpin dans le Sud-Est de la France. Il envisage en particulier les blocs siliceux ombragés occupés par le Grimmietum elatioris (avecGrimmia elatior Bruch,Orthotrichum rupestre Schleich,Grimmia funalis (Schwaegr.) Schimp.,G. doniana Sm.,Dicranum sauteri Schimp.) ainsi que les parois suintantes de gneiss (Blindio-Amphoridietum) colonisées parBlindia acuta (Huds) B.e.,Amphoridium mougeotti B.e.,Fissidens osmundoides Hedw.,Saccobasis polita (Nees) Bruch,Gymnostomum rupestre Schleich. Les rochers calcaires en exposition froide portent, sur le pourtour de l'Argentera-Mercantour l'association àEncalypta streptocarpa Hedw. etPlagiopus oederi (Schwaegr.) Schimp. (Encalypto-Plagiopetum) très largement répandue dans les Alpes du Sud, alors qu'au voisinage des cascades appara?t une formation tufogène montagnarde àHymenostylium recurvirostre (Hedw.) Dix etSouthbya nigrella (De Not) Spruce. Les tourbières àSphagnum acutifolium Warnst,S. teres Angst,S. platyphyllum Warnst,S. recurvum P.B.,Aulacomnium palustre (Hedw.) Schwaegr. etMeesea triquetra (Hedw.) Angst. semblent inféodées, dans les régions étudiées, au vieux massif cristallin (Lac Nègre, Boréon, Vallée des Merveilles) où elles se rencontrent à partir de 1900 mètres d'altitude. Enfin, les marécages sur calcaire ou sur flysch portent des peuplements à base deBryum pallens Sw.Philonotis fontana (Hedw.) Schwaegr.,Cratoneurum commutatum (Hedw.) Roth. avec par endroitsMeesea uliginosa Hedw. etAmblyodon dealbatus (Dicks) P.B.
Summary In this work, the author carries out a bryosociological study concerning the vegetation on rocks and bogs in the subalpine district of the high mountains of southern France. He considers particularly the siliceous blocks covered with carpets ofGrimmia elatior Bruch,Orthotrichum rupestre Schleich,Grimmia funalis (Schwaegr.) Schimp.,G. doniana Sm.,Dicranum sauteri Schimp. (Grimmietum elatioris) and the oozing gneiss-walls (Blindio-Amphoridietum) colonized byBlindia acuta (Huds) B.e.,Amphoridium mougeotti B.e.,Fissidens osmumdoides Hedw.,Saccobasis polita (Nees) Bruch., andGymnostomum rupestre Schleich. On calcareous rocks, in cold places, surrounding the Argentera-Mercantour, he found an association withEncalypta streptocarpa Hedw. andPlagiopus oederi (Schwaegr.) Schimp., (Encalypto-Plagiopetum) which is very common in the southern alps, and near waterfalls occurs a travertinic mountain-formation withHymenostylium recurvirostre (Hedw.) Dix andSouthbya nigrella (De Not) Spruce. The peat-bogs containingSphagnum acutifolium Warnst.,S. teres Angst,S. platyphyllum Warnst.,S. recurvum P.B.,Aulacomnium palustre (Hedw.) Schwaegr. andMeesea triquetra (Hedw.) Angst. seem to be particular to the old crystalline chain where we found them at an altitude of 1900 meters. Finally, calcareous or flysch-bogs present a cryptogamic vegetation withBryum pallens Sew.,Philonotis fontana (Hedw.) Schwaegr.,Cratoneurum commutatum (Hedw.) Roth. and the rareMeesea uliginosa Hedw. andAmblyodon dealbatus (Dicks) P.B.

Zusammenfassung In dieser Arbeit, führt der Verfasser ein bryosoziologisches Studien der Felsen und der Moore in der subalpinen Stufe Süd-Ost Frankreichs aus. Er beschreibt namentlich die Silikatbl?cke, die im Schatten der W?lder von dem Grimmietum elatioris (mitGrimmia elatior Bruch.,Orthotrichum rupestre Schleich.,Grimmia funalis (Schwaegr.) Schimp.,G. doniana Sm.,Dicranum sauteri Schimp.) bedeckt sind, und die feuchten Gneissw?nde (Blindio-Amphoridietum), die vonBlindia acuta (Huds.) B.e.,Amphoridium mougeotti B.e.,Fissidens osmundoides Hedw.,Saccobasis polita (Nees) Bruch.,Gymnostomum rupestre Schleich kolonisiert werden. Auf den kalkhaltigen Bl?cken, in der N?he des Argentera-Mercantour traf er eine Moosgesellschaft mitEncalypta streptocarpa Hedw. undPlagiopus oederi (Schwaegr.) Schimp. (Encalypto-Plagiopetum), die in den Süd-Alpen sehr h?ufig ist. An den Quellen und Wasserf?llen erscheint eine tufogene Bildung der montanen Stufe mitHymenostylium recurvirostre (Hedw.) Dix undSouthbya nigrella (De Not) Spruce. In unserer Gegend, sind die Torfmoore mitSphagnum acutifolium Warnst.,S. teres Angst,S. platyphyllum Warnst,S. recurvum P.B.,Aulacomnium palustre (Hedw.) Schwaegr., undMeesea triquetra (Hedw.) Angst. dem alten kristallartigen Gebirgsstock eng belehnt, wo wir sie immer ab 1900 meter gefunden haben. Endlich, tragen die Kalk oder Flysch-Sümpfe eine besondere Kryptogamenvegetation mitBryum pallens Sw.,Philonotis fontana (Hedw.) Schwaegr.,Cratoneurum commutatum (Hedw.) Roth. und manchmal die seltenenMeesea uliginosa Hedw. undAmblyodon dealbatus (Dicks) P.B.
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The genome of a fungal strain Penicillium chrysogenum strain HKF42, which can grow on 20% sucrose has been annotated for 7595 protein coding sequences. On mining of CAZymes, we could annotate a β-fructofuranosidase gene responsible for fructo-oligosaccharides (FOS) synthesis which is a known prebiotic. The enzyme activity was demonstrated and validated with the generation of FOS as kestose and nystose.  相似文献   

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The endo-β-1, 4-xylanase gene xynA from Aspergillus sulphureus, encoded a lack-of-signal peptide protein of 184 amino acids, was de novo synthesized by splicing overlap extension polymerase chain reaction according to Pichia pastoris protein’s codon bias. The synthetic DNA, composed of 572 nucleotides, was ligated into the downstream sequence of an α-mating factor in a constitutive expression vector pGAPzαA and electrotransformed into the P. pastoris X-33 strain. The transformed yeast screened by Zeocin was able to constitutively secrete the xylanase in yeast–peptone–dextrose liquid medium. The heterogenous DNA was stabilized in the strain by 20-times passage culture. The recombinant enzyme was expressed with a yield of 120 units/mL under the flask culture at 28°C for 3 days. The enzyme showed optimal activity at 50°C and pH 2.4–3.4. Residual activity of the raw recombinant xylanase was not less than 70% when fermentation broth was directly heated at 80°C for 30 min. However, the dialyzed xylanase supernatant completely lost the catalytic activity after being heated at 60°C for 30 min. The recombinant xylanase showed no obvious activity alteration by being pretreated with Na2HPO4-citric acid buffer of pH 2.4 for 2 h. The xylanase also showed resistance to certain metal ions (Na+, Mg2+, Ca2+, K+, Ba2+, Zn2+, Fe2+, and Mn2+) and EDTA. These biochemical characteristics suggest that the recombinant xylanase has a prospective application in feed industry as an additive.  相似文献   

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(1) In the overwhelming majority of genera of the family Ranunculaceae, includ ing its primitive genera, Caltha, Calathodes, and Trollius and the primitive genus of trib. Anemoneae, Anemone, the sepals are spreading and the stamens are glabrous. So, the as cending or upright sepals and hairy stamens of the sections Meclatis, Tubulosa, Viorna, and Atragene of the genus Clematis are secondary, and are accordingly considered as advanced characters, and those sections and the genus Archiclematis, closely related to Sect. Viorna Subsect. Connatae, more or less advanced groups. (2) In the sections Cheiropsis, Fruticella, and Viticella, which have glabrous stamens,some species have spreading sepals, and the others have ascending or upright sepals. In Sect. Clematis, all the species have spreading sepals and glabrous stamens, except for Clematis pinnata, which has ascending sepals and usually hairy stamen filaments. In Sect. Lasiantha with 2 species restricted to western U. S. A., C. lasiantha has glabrous stamens, while C. paucifiora has stamens hairy on fliaments. In Sect. Naraveliopsis with spreading sepals,the majority of species have glabrous stamens, but one species, C.liboensis, endemic to Guizhou Province, China, has hairy stamens. These facts just mentioned indicate that the evolution of sepals and stamens took place in several lineages independently in Clematis. (3) In Clematis, glabrous stamens of C.apiifolia, C.grata, and C.montana with linear filaments and oblong anthers, are similar to those of Caltha, Calathodes, Trollius, and Anemone. Thus, the linear filaments and oblong anthers are considered primitive characters in Clematis. On the other hand, lanceolatelinear filaments of C. tangutica and C. aethusifolia or oblanceolate -linear filaments of C. courtoisii and C. loureiriana and linear anthers of C. meyeniana and C. uncinata, and narrow-linear anthers of C. courtoisii and C. lanuginosa are considered advanced ones. In ease of stamens with hairs, stamens of C. henryi with densely villous filaments and those of C. kweichowensis with both filaments and anthers densely pubescent show more advanced condition than those of C. pinnata, C. heracleifolia, and C. tangutica, with sparsely puberulous filaments and glabrous antbers(Fig. 1 ). (4)The pedunculate, 2-bracteate dichasial cyme with several flowers may represent the primitive type of inflorescences in Clematis. Manyflowered panicle-like cymes as in C.gouriana and C. tsaii, or few-l-flowered cymes as in C. henryi and C. repens, and cymes lacking peduncles and bracts as in C. montana and C. pogonandra are all considered advanced. Besides, the fact that flowers arise from axillary buds of old branches shows also an advanced condition. (5)Sect. Clematis subsect. Pinnatae, with leaflets, inflorescence ramification, and stamens similar to those of C. heracleifolia, is considered intermediate between Sect. Clematis and Sect. Tubulosa. (6) Subsect. Clematis and Subsect. Rectae, and Subsect. Connatae and Subsect. Crispae are so closely related to each other respectively that it is difficult to ascertain the systematic position of some intermediate species between the two subsections of each pair in the absence of seedlings. So, in the present paper, following the classification of Clematis proposed by Tamura in 1967, I put Subsect. Clematis and Subsect. Rectae in Sect. Clematis, and Subsect. Connatae and Subsect. Crispae in Sect. Viorna. (7)According to the evolutionary tendencies mentioned above, a realignment of the sections and the infrasectional taxa of the Chinese Clematis is made. (8) Six subsections, 6 serise, 2 species, and 4 varieties are described as new, and 5 new combinations, 4 new ranks, and 2 new names are given. (9)The specific rank of C. tenuipes W.T. Wang, reduced to varietal renk in 1980, is restord. C. taiwaniana Hayata, reduced to synonomy of C. grata Wall. in 1991, is considered distinct from the latter in hairy adaxial surface of sepal and narrower achene with tapering apex. C. kerriana Drumm. & Craib and C. laxipaniculata Pei are proved to be conspecific to C. subumbellata Kurz and reduced to syn-onymy.  相似文献   

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Summary Clinical and cytogenetic findings in an infant girl with multiple congenital anomalies, principally anophthalmia, are presented. The patient's karyotype was 47,XX, +del(4)(pterq21), the largest partial trisomy of chromosome 4 reported. The possible mechanism of the origin of this abnormality is discussed.To whom offprint requests should be sent  相似文献   

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Kallmann syndrome (KAL) associates hypogonadotropic hypogonadism and anosmia, i.e. a deficiency of the sense of smell. Anosmia is related to the absence or the hypoplasia of the olfactory bulbs. Hypogonadism is due to GnRH deficiency, and is likely to result from the failed embryonic migration of GnRH-synthesizing neurons. These cells normally migrate from the olfactory epithelium to the forebrain along the olfactory nerve pathway. Kallmann syndrome is genetically heterogeneous. The gene responsible for the X-chromosome linked form of the disease, KAL-1, has been identified in 1991. KAL1 encodes a ~95 kDa glycoprotein of unknown function, which is present locally in various extracellular matrices during the period of organogenesis. The recent finding that FGFR1 mutations are involved in an autosomal dominant form of Kallmann syndrome (KAL-2), combined to the analysis of mutant mouse embryos that no longer express Fgfr1 in the telencephalon, suggests that the disease results from a deficiency in FGF-signaling at the earliest stage of olfactory bulb morphogenesis. We propose that the role of the KAL1 gene product, the extracellular matrix protein anosmin-1, is to enhance FGF-signaling, and suggest that the gender difference in anosmin-1 dosage (because KAL1 partially escapes X-inactivation) explains the higher prevalence of the disease in males.  相似文献   

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A growing group of migrants age in an environment in which the dominant language (L2) differs from their mother tongue (L1). This study considers the occurrence of a language barrier in accessing (information on) health and healthcare provisions, and under which circumstances a limited proficiency in the L2 negatively influences well-being for a group of older Turkish women in the Netherlands. Data from interviews with 39 Turkish females reveal that a limited L2 proficiency does not automatically result in a lower level of well-being. When individuals are well-embedded in a social network (and feel belonging to it), a limited L2 proficiency can be alleviated by either L1 assistance from their environment or by facilitating an interpreter in L2 situations. However, when such a network is absent, L2 situations can cause anxiety, which may have repercussions for well-being. Even though there is no clear one-on-one relationship between language and well-being, language does play a role in many (social) processes that influence well-being.  相似文献   

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International Journal of Peptide Research and Therapeutics - Most existing antimicrobial peptides (AMPs) are α-helical and cationic that exhibit typical amphipathic feature to facilitate...  相似文献   

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Ohne ZusammenfassungAn Abkürzungen werden stets verwendet: Bc Blastocoel - Bp Blastoporus - Cg Cingulum - D Dotterstock - Da Dotterstocksanlage - Dt Dorsaltaster - Em Embryo - Ent Entoderm - g Ganglion - gc Cerebralganglion - gca Cerebralganglionanlage - gm Mastaxganglion - gma Mastganglionanlage - Hb Harnblase - I Integument - Inta Integumentanlage - K Keimlagermutterzelle - Ka Kauer - Lt Öltropfen - M Mastax - MCg Matrixzellen des Cingulums - Mes Mesoderm - Mg Magen - Mga Magenanlage - Mgd Magendrüsen - Ms Muskel - Mu Mundbucht - Oda Oviduktanlage - Oes Ösophagus - Oesa Ösophagusanlage - Ov Ovar - Ova Ovaranlage - Oz Oozyte - Ozk Oozytenkern - Pc Pseudocoel - Ph Pharynx - Pha Pharynxanlage - Pr Protonephridium - Pz Propagationszellen - Q Quadrant - Rk Richtungskörper - T 1–4 Typen strahlengeschädigter Tiere - Ud Urdotterzelle - Ug Urgeschlechtszelle - Ugm Urgeschlechtsmutterzelle - Uk Urkeimzelle - Ur Urogenitalkanal - UV 40 kreisrunder Bestrahlungsfleck von 40 Durchmesser - UV alt nicht vergleichbarer Wert wegen veränderter Versuchsbedingungen.  相似文献   

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