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121.
Prolonged dormancy (hereafter dormancy), a phenomenon in which a perennial herbaceous plant does not sprout for one or more
years, is examined. The phenomenon may be more frequent than stated so far and discovery of its role in plant life history
and performance is still underway. Data from published papers was reviewed and all known species exhibiting dormancy were
analysed from the aspect of species ecological values. Adaptation to environmental factors (light, moisture, pH and nitrogen
as estimated by Ellenberg indicator values) influences the maximum duration of dormancy. A higher proportion of plants are
dormant in species that prefer to grow in good light conditions, dry sites and infertile soil. The duration of dormant period
is longer in species that prefer to grow in dry sites and/or calcareous soils. A range of factors, we believe, control plant
behaviour, however, it is suggested that environmental stress is the principal factor inducing dormancy. 相似文献
122.
Cachat J Stewart A Grossman L Gaikwad S Kadri F Chung KM Wu N Wong K Roy S Suciu C Goodspeed J Elegante M Bartels B Elkhayat S Tien D Tan J Denmark A Gilder T Kyzar E Dileo J Frank K Chang K Utterback E Hart P Kalueff AV 《Nature protocols》2010,5(11):1786-1799
Several behavioral assays are currently used for high-throughput neurophenotyping and screening of genetic mutations and psychotropic drugs in zebrafish (Danio rerio). In this protocol, we describe a battery of two assays to characterize anxiety-related behavioral and endocrine phenotypes in adult zebrafish. Here, we detail how to use the 'novel tank' test to assess behavioral indices of anxiety (including reduced exploration, increased freezing behavior and erratic movement), which are quantifiable using manual registration and computer-aided video-tracking analyses. In addition, we describe how to analyze whole-body zebrafish cortisol concentrations that correspond to their behavior in the novel tank test. This protocol is an easy, inexpensive and effective alternative to other methods of measuring stress responses in zebrafish, thus enabling the rapid acquisition and analysis of large amounts of data. As will be shown here, fish anxiety-like behavior can be either attenuated or exaggerated depending on stress or drug exposure, with cortisol levels generally expected to parallel anxiety behaviors. This protocol can be completed over the course of 2 d, with a variable testing duration depending on the number of fish used. 相似文献
123.
Piret Kalmus Toomas Orro Andres Waldmann Raivo Lindjärv Kalle Kask 《Acta veterinaria Scandinavica》2009,51(1):32
Background
The main objective of this study was to estimate the effect of supplementation with Saccaromyces cerevisiae (SC) (Yea-Sacc® 1026) on milk production, metabolic parameters and the resumption of ovarian activity in early lactation dairy cows.Methods
The experiment was conducted during 2005/2006 in a commercial tied-house farm with an average of 200 milking Estonian Holstein Friesian cows. The late pregnant multiparous cows (n = 46) were randomly divided into two groups; one group received 10 g yeast culture from two weeks before to 14 weeks after calving. The groups were fed a total mixed ration with silages and concentrates. Milk recording data and blood samples for plasma metabolites were taken. Resumption of luteal activity was determined using milk progesterone (P4) measurements. Uterine bacteriology and ovarian ultrasonography (US) were performed and body condition scores (BCS) and clinical disease occurrences were recorded. For analysis, the statistical software Stata 9.2 and R were used to compute Cox proportional hazard and linear mixed models.Results
The average milk production per cow did not differ between the groups (32.7 ± 6.4 vs 30.7 ± 5.3 kg/day in the SC and control groups respectively), but the production of milk fat (P < 0.001) and milk protein (P < 0.001) were higher in the SC group. There was no effect of treatment on BCS. The analysis of energy-related metabolites in early lactation showed no significant differences between the groups. In both groups higher levels of β-hydroxybutyrate (BHB) appeared from days 14 to 28 after parturition and the concentration of non-esterfied fatty acid (NEFA) was higher from days 1–7 post partum (PP). According to US and P4 results, all cows in both groups ovulated during the experimental period. The resumption of ovarian activity (first ovulations) and time required for elimination of bacteria from the uterus did not differ between the groups.Conclusion
Supplementation with SC had an effect on milk protein and fat production, but did not influence the milk yield. No effects on PP metabolic status, bacterial elimination from the uterus nor the resumption of ovarian activity were found.124.
Propylthiouracil (PTU) is one of the most common drugs used in hyperthyroidism in general medical practice. PTU may also trigger the development of thyroid lymphoma through induction of abnormal immunological events in thyroid tissue. 相似文献
125.
Species delimitation in Cystoderma and Cystodermella was evaluated based on ITS and LSU rDNA sequences as well as morphological data. Two species of Cystoderma are synonymised with C. carcharias and three species with C. jasonis, distinguishing the synonymised taxa as varieties of these accepted species. Analyses of partial LSU rDNA sequences revealed Cystoderma and Cystodermella as distinct monophyletic genera, with Ripartitella representing a well-supported sister group of the latter. Phaeolepiota aurea represents either an unsupported sister group or member of Cystoderma in the phylogenies based on LSU and ITS sequences rDNA data, respectively. The tribe Cystodermateae sensu Singer did not appear monophyletic according to analyses of LSU sequences. On the basis of these data, the phylogenetic relationships among most of the analyzed genera could not be resolved unequivocally. 相似文献
126.
Lõivukene K Kermes K Sepp E Adamson V Mitt P Jürna M Mägi H Kallandi U Otter K Naaber P 《Antonie van Leeuwenhoek》2006,89(3-4):367-371
A total of 560 invasive and 1062 non-invasive isolates were collected. The antimicrobial susceptibility of invasive versus non-invasive Pseudomonas aeruginosa, Acinetobacter baumannii, and Klebsiella pneumoniae isolates were evaluated using the E-tests. The equal domination of Gram-negative among both invasive and non-invasive pathogens was estimated in our study if contaminants were excluded. The emergence trend of Gram-positive microbes especially of coagulase negative staphylococci may be proved only after application of exclusive algorithms. Due to similar susceptibility, the data of non-invasive Gram-negative pathogens can be useful to predict resistance of invasive ones. Also, the surveillance of invasive pathogens provides useful information about the general susceptibility of pathogens. 相似文献
127.
F. A. Huntingford G. Andrew S. Mackenzie D. Morera S. M. Coyle M. Pilarczyk S. Kadri 《Journal of fish biology》2010,76(7):1576-1591
Individual common carp Cyprinus carpio were screened repeatedly for risk taking (rate of exploration of a novel, potentially dangerous environment) and for competitive ability (success in gaining access to a spatially restricted food source). Marked differences in behaviour were evident, and significant consistency in individual responses across trials was found for both risk taking and competitive ability. In addition, there was a significant positive relationship between individual performance in these two contexts, with fish that explored more quickly in the novel environment tending to be among the first to gain access to restricted food. In two follow‐up studies, resting metabolic rate, blood lactate and glucose and the expression of the cortisol receptor gene in the head kidney and brain were compared in fish from the two extremes of the risk‐taking spectrum. Mass‐specific metabolic rate was significantly higher in risk‐taking than in risk‐avoiding fish, while plasma lactate and glucose concentrations and expression of the cortisol receptor gene were lower. It was concluded that a behavioural syndrome based on boldness and aggression exists in C. carpio, as it does in many other animals, and that this is associated with differences in metabolic and stress physiology (down to the genomic level) similar to those described in animals with different coping strategies. 相似文献
128.
Two patients with mast cell disease presented with unusual features. In one the absence of skin lesions made the diagnositic problem a challenging one. Certain of the laboratory findings, especially those related to the serum cholesterol concentration and platelet function tests, were particularyl interesting. Chemotherapy induced partial remission. The second patient had a long, relatively benign course complicated by two episodes of herpes zoster, the last being associated with the Landry-Guillain-Barre syndrome. In both patients the skeletal abnormalities were radiologically similar. When these are present they should be considereed sufficiently characteristic to indicate strongly a diagnosis of mastocytosis. 相似文献
129.
Yan-Ling Chen Régine Capeyrou Odile Humbert Sa?da Mouffok Yasmine Al Kadri Simon Lebaron Anthony K. Henras Yves Henry 《Nucleic acids research》2014,42(11):7330-7345
We provide evidence that a central player in ribosome synthesis, the ribonucleic acid helicase Prp43p, can be activated by yeast Gno1p and its human ortholog, the telomerase inhibitor PINX1. Gno1p and PINX1 expressed in yeast interact with Prp43p and the integrity of their G-patch domain is required for this interaction. Moreover, PINX1 interacts with human PRP43 (DHX15) in HeLa cells. PINX1 directly binds to yeast Prp43p and stimulates its adenosine triphosphatase activity, while alterations of the G patch abolish formation of the PINX1/Prp43p complex and the stimulation of Prp43p. In yeast, lack of Gno1p leads to a decrease in the levels of pre-40S and intermediate pre-60S pre-ribosomal particles, defects that can be corrected by PINX1 expression. We show that Gno1p associates with 90S and early pre-60S pre-ribosomal particles and is released from intermediate pre-60S particles. G-patch alterations in Gno1p or PINX1 that inhibit their interactions with Prp43p completely abolish their function in yeast ribosome biogenesis. Altogether, our results suggest that activation of Prp43p by Gno1p/PINX1 within early pre-ribosomal particles is crucial for their subsequent maturation. 相似文献
130.
Abid Ghassen Ouertani Rim Nefissi Jebara Salwa Harzalli Boubakri Hatem Muhovski Yordan Ghouili Emna Abdelkarim Souhir Chaieb Oumaima Hidri Yassine Kadri Safwen El Ayed Mohamed Elkahoui Salem Barhoumi Fethi Jebara Moez 《Physiology and Molecular Biology of Plants》2020,26(6):1173-1186
Physiology and Molecular Biology of Plants - Drought stress is one of the most prevalent environmental factors limiting faba bean (Vicia faba L.) crop productivity. β-aminobutyric acid (BABA)... 相似文献