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381.
Plant growth and performance in snowbed communities are strongly influenced by the length of the growing period remaining after the snowmelt date. Under the scenario of climate change, studying the phenological responses of snowbed species to variations in snowmelt date might be crucial to understand their ability to adapt and survive under changing conditions. We studied 13 plant species from contrasting biological and ecological groups (i.e. ‘snowbed specialists’, ‘preferential species’ and ‘generalist species’) growing in four snowbed plots with siliceous substrates in the Central Pyrenees. These species were monitored for two consecutive years and in two different microsites, namely the central part and the peripheral part of each snowbed plot. We characterised their phenological cycle and length and their success in seed setting, measured as the number of individuals succeeding in dispersing their seeds.  相似文献   
382.
Objective: With anthropometric models using skinfolds and circumferences, we studied changes in the percentage of subcutaneous fat in the total cross‐sectional area (SF%) at four body sites in obese women, before and after weight loss induced by 6 months of caloric restriction. Research Methods and Procedures: In 61 obese women [31 African Americans and 30 whites; ages, 24 to 68 years; body mass index (BMI), ≥28kg/m2], we measured SF% at the midpoint of the upper arm and thigh and the waistline and hipline, and we measured the percentage of total body fat by DXA before (Obs#1) and after (Obs#2) a 6‐month nonintervention control period and then after 6 months on a 1200 kcal/d diet (Obs#3). Results: The mean body weight and BMI increased (1.8 kg and 0.61 kg/m2; p = 0.0001), but there were no significant changes in any other body composition measurements from Obs#1 to Obs#2. The means of Obs#3 for weight and BMI decreased by 11%, and the percentage of total body fat decreased by 13% of Obs#2 mean values (p = 0.0001). The mean SF% at each site decreased 7.6% to 18.0% of the Obs#2 mean values (p < 0.001). The SF% decreases were greater at mid‐arm and mid‐thigh than in the cross‐sectional regions at the waistline and hipline (p = 0.05). There was no interaction between age or ethnicity (p > 0.2). Conclusions: In obese women, caloric restriction alone reduces anthropometrically measured subcutaneous fat proportionally more in peripheral than in central regions.  相似文献   
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Although lesbian women have a variety of ways to become mothers, an increasing number of lesbian couples attend fertility centres asking for donor insemination. The practice of inseminating lesbian couples remains a controversial topic within the reproductive medicine world. A review of the literature did not reveal harmful effects of lesbian motherhood on child development. Furthermore, this treatment is highly effective with an expected cumulative pregnancy rate of 60% after three intra-uterine inseminations with superovulation using clomifene citrate. The only objection to medically assisted procreation in these couples is therefore purely ethical. The extensive experience of the AZ-VUB Centre for Reproductive Medicine that played a pioneer role in this field, is illustrated in this article.  相似文献   
386.
Résumé La végétation des îles Baléares est nettement méditerranéenne. Les climax forestiers appartiennent à l'alliance méditerranéenne septentrionale du Quercion ilicis (parties pluvieuses de Majorque et de Minorque) et à l'alliance méditerranéenne méridionale de l'Oleo-Ceratonion (Querco-Lentiscetum d'affinité ibérique à Ivice; groupement àCeratonia siliqua etCneorum tricoccum dans la partie sèche de Majorque, groupement àOlea europaea etPrasium majus dans la partie la plus sèche de Minorque). Des groupements riches en endémiques caractérisent le karst des hauts sommets de Majorque et les rochers littoraux des côtes venteuses de Majorque et de Minorque. L'influence tyrrhénienne, importante dans les Gymnésies (Majorque et Minorque) est bien plus faible dans le groupe des Pithyuses (Ivice et Formentera), plus rapproché de la Péninsule Ibérique.
Summary The vegetation of the Balearic Islands is pure mediterranean. The climax forests belong to the northern mediterranean alliance of the Quercion ilicis (rainy regions in Majorca and Menorca) and to the southern mediterranean community of the Oleo-Ceratonion (Querco-Lentiscetum with Iberic affinity in Ibiza; community withCeratonia siliqua andCneorum tricoccum in the dry region in Majorca, community withOlea europaea andPrasium majus in the driest region in Menorca). Communities rich in endemic plants characterize the karst of the high summits in Majorca, and coastrocks of the windy shores in Majorca and Menorca. The tyrrhenic influence, important in the Gymnesies (Majorca and Menorca), is more feeble in the group of the Pithyuses (Ibiza and Formentera), nearer to the Iberic Peninsula.

Zusammenfassung Die Vegetation der Balearischen Inseln ist rein mediterran. Die Klimaxwälder gehören zu dem nördlichen Mittelmeerverband des Quercion ilicis (regnerische Gegenden von Mallorca und Menorca) und dem südlichen Mittelmeerverband des Oleo-Ceratonion (Querco-Lentiscetum mit iberischer Verwandtschaft auf Ibiza; Gesellschaft mitCeratonia siliqua undCneorum tricoccum in der trockenen Gegend von Mallorca, Gesellschaft mitOlea europaea undPrasium majus in der trockensten Gegend von Menorca). Endemitenreiche Pflanzengesellschaften charakterisieren den Karst der hohen Gipfel von Mallorca, und die Küstenfelsen der windreichen Küsten Mallorcas und Menorcas. Der tyrrhenische Einfluß, bedeutend in den Gymnesien (Mallorca und Menorca), ist entschieden schwächer in der Gruppe der Pithyusen (Ibiza und Formentera), die der Iberischen Halbinsel näher liegt.
  相似文献   
387.
Between days 36-38 of pregnancy equine trophoblastic cells of the chorionic girdle migrate and form endometrial cups. Just prior to invasion, the chorionic girdle cells express high levels of polymorphic, paternally inherited, major histocompatibility complex (MHC) class I antigens. Their descendents, the mature, invasive trophoblast cells of the endometrial cups, however, express low or undetectable levels of MHC class I antigens by day 44 of pregnancy. Experiments with MHC compatible pregnancies, the study of residual chorionic girdle cells that had failed to invade the endometrium and remained on the surface of a conceptus, and the study of chorionic girdle cells recovered on days 34-36 of pregnancy and then maintained in vitro for up to 24 days strongly suggest that the reduction of MHC class I antigen expression by mature invasive trophoblast cells of the endometrial cups is developmentally regulated. This phenomenon does not appear to be induced by a maternal antibody response or by other uterine factors acting after the chorionic girdle trophoblast cells invade the endometrium.  相似文献   
388.
Most foldback elements are defective due to the lack of coding sequences but some are associated with coding sequences and may represent the entire element. This is the case of the NOF sequences found in the FB of Drosophila melanogaster, formerly considered as an autonomous TE and currently proposed as part of the so-called FB-NOF element, the transposon that would be complete and fully functional. NOF is always associated with FB and never seen apart from the FB inverted repeats (IR). This is the reason why the FB-NOF composite element can be considered the complete element. At least one of its ORFs encodes a protein that has always been considered its transposase, but no detailed studies have been carried out to verify this.  相似文献   
389.
An enantiomerically pure (R)-2-methylpyrrolidine-based anilino squaraine crystallizes in two chiral polymorphs adopting a monoclinic C2 and an orthorhombic P212121 structure, respectively. By various thin-film preparation techniques, a control of the polymorph formation is targeted. The local texture of the resulting textured thin films is connected to the corresponding optical properties. Special attention is paid to an unusual Davydov splitting, the anisotropic chiroptical response arising from preferred out-of-plane orientation of the crystallites, and the impact of the polymorph specific excitonic coupling.  相似文献   
390.
The presence of human blood-group antigens in developing and adult hypothyroid rat cochleas was analyzed using antibodies directed against antigens H and B. During postnatal development, hypothyroid rat cochleas exhibited a highly selective expression of both B and H antigens, mainly at the hair cell level. Labeling for antigen B was found throughout the hair cells, whereas the antibody directed against antigen H selectively labeled the apical part of these cells. These immunostaining patterns were similar to those found in normal (euthyroid) rat cochleas, but antigenic expression periods were clearly prolonged. Thus, whereas in normal rat cochleas, the B and H antigenic expression disappears from postnatal day (PD) 9 on, in cochleas of hypothyroid rats the reactivity was intense until PD15; it decreased from this developmental stage, and was negative or only faintly positive at PD30. Therefore, in congenital hypothyroidism, hair cell immunoreactivity is present at developmental stages that are negative in normal rat cochleas. These results suggest that human blood-group antigen expression on the developing cochlear hair cells of rats is modulated by thyroxine and that thyroxine is necessary for the temporal expression pattern and secretion of normal glycoproteins.  相似文献   
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