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1.
Zusammenfassung Verf. erläutert einen noch nicht geschilderten morphologischen Befund. Während der bei Kaninchen mit Thorotrast ausgeführten Speicherungsuntersuchungen des retikulär-endothelialen Systems hat er beobachten können, daß die Kupffer-Sternzellen bei seit langer Zeit behandelten Tieren aus ihrem normalen Sitz im hepatischen Acinus gegen seine zentrale Ader gewandert sind, indem sie um dieselbe einen Umkreis von mit Thorotrast belasteten Kupffer- Sternzellen bildeten und indem sie auch in das Leberaderblut eindrangen. Dagegen findet man bei seit kurzer Zeit behandelten Tieren die mit Thorotrast belasteten Zellen im Acinus, wie gewöhnlich, diffus verteilt. Verf. erörtert diese Befunde im Zusammenhang mit der Bedeutung und dem Wesen der KupfferSternzellen.  相似文献   

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Abstract

Vegetation and environment in the Marche and related problems of protection. – The « Marche » region is situated in central Italy and corresponds with the natural region east of the Appennine ridge and spreading as far as the coast which is washed by the Adriatic Sea.

As to the climate, we may distinguish a coastal strip with Mesomediterranean climate with dry season, corresponding to the distribution area of Quercus ilex; a hilly strip with Submediterranean climate, corresponding to the distribution area of Quercus pubescens; a mountain strip with temperate axeric climate with sub-dry period, corresponding to the distribution area of Fagus silvatica and finally a high mountain strip with cold axeric climate, corresponding to altitude pastures. The Marche vegetation is shown in the vegetation map of Fabriano sheet (scale 1:50,000) plotted according Ozenda's vegetational series.

The following vegetation series have been plotted: submediterranean series of Quercus ilex; series of thermophilic oak wood with priority of Quercus pubescens or Quercus cerris; series of Ostrya carpinifolia; series of Quercus petraea and series of Fagus silvatica.

As far as the problems to safegard environment are concerned, a plan is given providing for the institution of 4 complete nature reserves, 34 nature reserves, and 9 regional nature parks among which those of Monte Conero, of Monti Sibillini and Monti della Laga.  相似文献   

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Questo lavoro vede la luce con un ritardo di circa otto anni, per le difficultà inerenti lo stato di guerra. A causa delle stesse ragioni, le collezioni dei lieviti isolati e studiati è andata perduta; ma data la frequenza e la relativa loro costanza nel substrato d'isolamento, non dovrebbe essere difficile reisolarli, se desiderato.  相似文献   

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Abstract

Observations on the development cycle of the buds of male and female specimens of Ginkyo biloba L. – A study of the buds of long shood and short shoot of male and female Ginkyo biloba L. individuals reveals the following: 1) All the buds of the male individuals are bigger and round in shape while those of the female individuals are smaller and conical. 2) Among individuals of the same sex there are no differences between the buds of long and short shoots except that the latter are always bigger. 3) All the buds, both male and female, show a constant number of buds scales (7–14), embryonic leaves (3–7) and leaf primordia (3–4). 4) The increase in diameters is greater in the male than in the female buds. 5) When opening, the buds of the male short shoots can get as big as 11,5 mm × 11,5 mm and those of the female short shoots 5 mmx4 mm. At this time, the long shoots of both sexes show a less marked differences in size (♂ 5 mm × 5 mm; 9 4 mm × 3,5 mm). 6) The male buds of both long and short shoots are always mixed, that is they are provided with a very small apex and pollen sacs. Only on exceptional cases has sterility been observed. On the other hand female buds are mixed, that is they are provided with a shoot apex and ovules, only in the long shoots of three or more years of age and not always; while the buds of the long shoots are always sterile. 7) Opening of the buds, which in both sexes occurs from the base upwards, takes place at the middle of March in the male and in the first decade of April in the female individuals. 8) The appearence of sex, starting from the base, takes place at an earlier time in male individuals. In fact in the buds of the male short shoots it appears as early as July. In the buds of the female short shoots it appears in October. 9) Pollen cones do not appear at the same time in all the buds of the two types of shoot. They are found in the buds of the short shoots in July, in October in the lateral buds of the long shoots and in November in the terminal buds of the same type of shoots. 10) Ovules appear only in some buds of short shoots three or more year old. They are never present in the long and short shoots one or two year old buds. 11) The dates of appearance of the pollen cones and ovules in our Florentine specimens are exactly the same as those reported by SPRECHER (1907) for the Ginkyo plants growing in Geneva.  相似文献   

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Riassunto E' stata studiata l'istogenesi e l'istochimica della ghiandola sottomandibolare e sottolinguale di embrione di topo, in condizioni di sviluppo normale e in cultura organotipica in vitro. In condizioni normali l'attività secretrice diviene dimostrabile con mezzi istochimici al 16 giorno di gestazione, come materiale intracellulare. La secrezione presenta fino dall'inizio reazione positiva ai metodi del PAS e di Hale, ed è colorabile col blu alcian. Al 17 giorno compaiono fra le due ghiandole differenze nell'aspetto morfologico del secreto, nell'intensità delle suddette reazioni istochimiche, e nel comportamento rispetto al blu di toluidina che dopo solfatazione dà colorazione metacromatica nella sottolinguale, ma non nella sottomandibolare. Ciò indica che il componente polisaccaridico del secreto ha caratteristiche un po' diverse nelle due ghiandole.Sono state eseguite culture in vitro di ghiandole al 13 giorno di gestazione, su un coagulo di plasma e di estratto embrionale di pollo. Al momento dell'espianto, esse sono all'inizio della loro differenziazione, e sono formate ciascuna da un cordoncino epiteliale e da una gemma solida, entro una comune capsula mesenchimale. Il processo di ramificazione si svolge più lentamente che in vivo, ma la secrezione compare alla stessa età totale. Le ghiandole si sono sviluppate in vitro per 10 giorni e le loro caratteristiche istochimiche sono apparse eguali a quelle che si osservano in condizioni normali di sviluppo.
Summary Histogenesis and histochemistry of submandibular and sublingual glands of mouse embryo were studied both during normal development and in vitro. In normal conditions secretory activity becomes detectable by histochemical methods at the 16th day of gestation as intracellular material. From the start, secretion shows a positive reaction to the PAS and Hale's method, and stains with alcian blue. At the 17th day differences may be shown between the two glands in the morphological features of the secretion, in the intensity of the above said histochemical reactions, and in the behaviour towards toluidine blue, which after sulfation gives metachromatic staining in the sublingual, but not in the submandibular gland. This indicates that the polysaccharidic component of the secretion has different characters in the two glands.Cultures in vitro were made of glands at the 13th day of gestation, on a clot of chicken plasma and embryo extract. At explantation time, they are just beginning their differentiation, and both consist of an epithelial cord and a solid bud, contained in a common mesenchymal capsule. The ramification process goes on at a slower rate in vitro than in vivo, but secretion appears at the same total age. The glands developed in vitro for 10 days and their histochemical features appeared to be comparable to those which were observed in normal developmental conditions.


Lavoro eseguito coi mezzi forniti da contratti di ricerca dell'U.S.A.E.C. (NYO-3355-10) e dell'Euratom (043-65-1 BIO I) e con un contributo del C.N.R.  相似文献   

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Il presente lavoro è stato eseguito nell' Istituto di Anatomia e Fisiologia Comparate dell' Università di Palermo, diretto dal prof. F.Raffaele. Il manoscritto relativo era pronto fin dall' ottobre dell' anno passato, ma il mio trasferimento da Palermo a Pavia e varie altre circostanze mi avevano finora impedito dal darvi l'ultima mano.Al prof.Raffaele che ha seguito con efficace interessamento queste ricerche e che ha voluto adesso gentilmente rivedere anche il manoscritto, i miei più cordiali ringraziamenti.  相似文献   

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Abstract

Observations on vegetative growth and leghemoglobin contents of root nodules of pea and bean plants after flower bud removal. — These studies found their origin in the papers by MATTIROLO (1899) on the effect of the removal of flowers as they formed in bean plants; he observed that deflowering resulted in extraordinary plant growth, stem branching and flower buds formation as well as in a delayed root nodule senescence. In the light of modern knowledge of the leghemoglobin role in symbiotic nitrogen fixation, the aim of the present research was to ascertain any possible relation between flower bud removal and haeme pigment contents in the root nodules. The experiments were carried out during two growing seasons (1966 and 1970) using Vicia faba L. cv. Regina and Pisum sativum L. cv. Senatore during 1966 and cv. Vittoria in 1970. In both control and test plants the seasonal trends of average plant height, fresh and dry weight of vegetative portions, fresh and dry weight of root system, fresh weight of nodules, root nodule leghemoglobin concentration and total leghemoglobin content per plant, were determined. The data obtained are quoted in Table 2 and reported in Figures 1, 2, and 3. The removal of flower buds caused in both species: an increased plant growth, a marked stem branching, a longer blooming period, an increased flower number, an increased root nodule number and a certain delay in root nodule reabsorption. Deflowering did not significantly extend — at least in the species studied — life span (senescence was delayed only of one week). On the basis of these and of other Authors' results, we conclude that deflowering may actually delay senescence; the size of this delay, however, depends on the plant species considered and is fairly negligible both in pea and bean. The different effects of deflowering and of preventing floral induction on life span extension, are discussed, and these facts lead to consider floral induction as the onset of a chain of processes leading annual plants toward senescence in a more or less delayable, but definitive way. After having stressed the generally accepted importance of leghemoglobin concentration as an index of nodule nitrogen fixing ability, a correlation between biomass increase of test plants and number and total weight increase of root nodules, is put in evidence. No correlation between test plant biomass and the leghemoglobin concentration in root nodules, was however observed. Leghemoglobin concentration in root nodules is known to change in connection with various factors depending either on host plants and on Rhizobium strains and also in connection with several environmental conditions. Any prevented flower onset (ROPONEN and VIRTANEN, 1968) and deflowering (our data) however exerted no significant influence. The effects of flower bud removal were therefore the following: increased stem, leaf and root weights and increased root nodule number; no difference between control and test plants was however observed as regards size and leghemoglobin concentration of root nodules and hence probably no difference as regards their nitrogen fixing ability.  相似文献   

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Abstract

The use of life-forms in phytosociological classifications: an example with data from xerophilous pastures.—The classification power of life-forms connecting to phytosociological data processing for xerophilous pastures of Central Southern Apennine (ecological classification) is discussed. Saturejo montanae-Brometum erecti Avena, Blasi 1979 and Seslerio nitidae-Brometum Bruno 1968 are compared on the basis of their weighted life-forms spectra. The high correlation between classification obtained by floristic data and classifications by life-forms is stressed.  相似文献   

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Abstract

A phytosociological study of the Quercus ilex woods in the surroundings of Siena (Italy). – Numerous stands of Quercus ilex woods around Siena have been studied phytosociologically and compared to the better known similar forests of Southern France. As a rule the Siennese Quercus ilex woods (Table 1) can not be considered to belong to the association Quercetum mediterraneo-montanum Br.-Bl. 1936 because of the absence of various significant central European and montane species, nor to Quercetum galloprovinciale because of the presence of too great a number of Quercetalia pubescenti-petraeae and Querco-Fagetea species. Only rarely communities similar to the first mentioned association have been found: i.e. on Mount Cetona at 1.800 feet and in two particularly cool and humid localities at a lower height (Table 2). Taking into account the way these woods have been managed for centuries it can be concluded that they are mixed formations of Quercetum galloprovinciale and an oakwood association belonging to the order Quercetalia pubescenti-petraeae; the exploitation techniques have caused the evergreen oak to become dominant therefore creating conditions favourable to the more thermophilous and shade loving plants characterics of Q. ilex woods and at the same time bringing about a sharp decrease in the number of the light demanding species typical of deciduous oakwoods.  相似文献   

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Summary

The changes in carbohydrate and phosphorus metabolism of tomato ovaries stimulated to growth by pollination or auxin treatment found in previous studies prompted an investigation of the enzymatic systems concerned. In this research, the effects of pollination and of auxin treatment on phosphorylase and on phosphatase activity were studied. Phosphatase splitting inorganic P from adenosine triphosphate was characterized as different from that acting on glycero- and hexose-phosphate by the difference in inhibition by beryllium and fluoride.

Two phases of growth occurring during the earlier stages of fruit development were clearly defined by the behavior of the enzymes considered. During the first (induction) phase both phosphomonoesterase and ATP-ase activity markedly dropped. This was followed by a marked rise in activity during the later stages of growth.

Phosphorylase activity, unlike that of the phosphatases, showed no relationship to the two phases of growth, and increased steadily during the period of observation. This agreed with the rate of starch synthesis observed in the growing auxin treated or pollinated tomato fruits.

Changes in the activity of these enzymes in the not pollinated, not auxin treated ovaries during the period of observation were, on a comparative basis, very small.  相似文献   

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Summary

In this research we describe the embryology relating to the ovule from the first stages of the archesporium to the grown up gametophyte in Rhamnus Alaternus L., Colletia cruciata Gill. et Hook., Colletia spinosa Lam. Paliurus aculeatus Lam. and Hovenia dulcis Thunb. We ascertain everywhere a very analogous behaviour in the formation of the gametophyte, which is of the Normal type, except a very few irregularities, while the condition of the archesporium is various in the different species. We describe also the microsporogenesis observed in three species. We establish the aploid numbers 12 for Paliurus aculeatus, 11 for Colletia spinosa and the diploid number 22 for Colletia cruciata. We describe at last a remarkable parthenocarpic capacity in Colletia spinosa and the sterility probably due to a scanty vital mutation in an individuum of Paliurus aculeatus.  相似文献   

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