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811.
Annual egg and chick production and breeding success at the Adélie penguin (Pygoscelis adeliae) colony Edmonson Point (74°21′S–165°10′E), Victoria Land, is presented for eight breeding seasons between 1995 and 2005.
During this period the colony consisted of 10–13 subcolonies and averaged 2098 ± 278 breeding pairs. A sample of over 100
nests (114–150), belonging to two subcolonies, was monitored each year. Some breeding parameters remained constant while others
showed substantial annual variation. Laying date showed little variation, and laying was highly synchronous: 82.5% of clutches
were initiated in a 10-day period, 9–18 November. In contrast, clutch size (1.77–1.97) and incubation period (34.4 ± 2.5)
varied significantly. Variation among years was also recorded in hatching success (from 58 to 86%) and breeding success. This
last parameter, measured as number of chicks reared to crèche per nest with eggs, varied between 0.34 and 0.97. 相似文献
812.
Antonio Picarelli Marco Di Tola Anna Vallecoccia Valerio Libanori Mirella Magrelli Marta Carlesimo Alfredo Rossi 《Biological trace element research》2011,139(2):151-159
On contact with the skin, nickel may cause allergic contact dermatitis, which can be diagnosed by an epicutaneous patch test.
Nickel exposure via the intestinal mucosa can induce diarrhea, abdominal pain, and swelling. The aim of the present study
was to investigate the relationship between these symptoms and nickel intake by means of a novel oral mucosa patch test. Eighty-six
patients with intestinal symptoms related to ingestion of nickel-containing foods were submitted to epicutaneous and oral
mucosa patch tests for nickel. All patients with positive oral mucosa patch test results were subject to a low-nickel diet
and monitored over time. Skin lesions were observed in 33 out of 86 (38.4%) patients evaluated by the epicutaneous patch test.
Mucosal lesions were seen in 53 out of 86 (61.6%) patients given the oral mucosa patch test. After 2 months of a low-nickel
diet, 52 out of 53 (98.1%) patients showed an improvement of their symptoms. There is a significant correlation between response
time of the oral mucosa patch test and the latency of symptoms after ingestion of nickel-containing foods. Consequently, the
oral mucosa patch test can be used to recognize and study the adverse effects of dietary nickel exposure that could be defined
as allergic contact mucositis. A low-nickel diet is also shown to be an effective treatment for this condition. 相似文献
813.
Lorenzo Parri Ada Fort Anna Lo Grasso Marco Mugnaini Valerio Vignoli Clemente Capasso Sonia Del Prete Maria Novella Romanelli Claudiu T. Supuran 《Journal of enzyme inhibition and medicinal chemistry》2021,36(1):393
In this paper, the efficiency of the carbonic anhydrase (CA) enzyme in accelerating the hydration of CO2 is evaluated using a measurement system which consists of a vessel in which a gaseous flow of mixtures of nitrogen and CO2 is bubbled into water or water solutions containing a known quantity of CA enzyme. The pH value of the solution and the CO2 concentration at the measurement system gas exhaust are continuously monitored. The measured CO2 level allows for assessing the quantity of CO2, which, subtracted from the gaseous phase, is dissolved into the liquid phase and/or hydrated to bicarbonate. The measurement procedure consists of inducing a transient and observing and modelling the different kinetics involved in the steady-state recovery with and without CA. The main contribution of this work is exploiting dynamical system theory and chemical kinetics modelling for interpreting measurement results for characterising the activity of CA enzymes. The data for model fitting are obtained from a standard bioreactor, in principle equal to standard two-phase bioreactors described in the literature, in which two different techniques can be used to move the process itself away from the steady-state, inducing transients. 相似文献
814.
815.
816.
817.
Ramona Vinci Daniela Pedicino Alessia DAiello Pellegrino Ciampi Myriana Ponzo Alice Bonanni Giulio Russo Rocco Antonio Montone Massimo Massetti Filippo Crea Giovanna Liuzzo 《Journal of enzyme inhibition and medicinal chemistry》2021,36(1):785
Acute Coronary Syndromes (ACS) with plaque erosion display dysregulated hyaluronan metabolism, with increased hyaluronidase-2 (HYAL2) expression. However, the expression and the role of this enzyme on platelets has never been explored. We evaluated the platelet’s HYAL2 (pltHYAL2) levels on I) stable angina (SA) and II) ACS patients, furtherly sub-grouped in Intact-Fibrous-Cap (IFC) and Ruptured-Fibrous-Cap (RFC), according to Optical Coherence Tomography. We assessed the HYAL2 role through an in vitro model setting of co-cultured monocytes and platelets, before and after treatment with low-molecular-weight hyaluronic acid (HA) as pro-inflammatory stimulus and with or without HYAL2-antibody to inhibit HYAL2 activity. ACS patients exhibit higher pltHYAL2 levels comparing to SA, with the higher expression for IFC group. The addition of HYAL2-antibody significantly reduced the percentage of monocyte-platelet binding, suggesting that pltHYAL2 enrichment at the site of the culprit lesion is a key mediator in the systemic thrombo-inflammatory status of ACS presenting with plaque erosion. 相似文献
818.
Dr. Giancarlo Pizza Francesco Chiodo Vincenzo Colangeli Francesco Gritti Enzo Raise Hugh H. Fudenberg Caterina De Vinci Dimitri Viza 《Biotherapy》1996,9(1-3):41-47
Twenty five HIV-1-infected patients, at various stages (CDC II, III and IV) were treated orally with HIV-1-specific transfer
factor (TF) for periods varying from 60 to 1870 days. All patients were receiving antiviral treatments in association with
TF. The number of lymphocytes, CD4 and CD8 subsets were followed and showed no statistically significant variations. In 11/25
patients the number of lymphocytes increased, whilst in 11/25 decreased; similarly an increase of the CD4 lymphocytes was
observed in 11/25 patients and of the CD8 lymphocytes in 15/25. Clinical improvement or a stabilized clinical condition was
noticed in 20/25 patients, whilst a deterioration was seen in 5/25. In 12/14 anergic patients, daily TF administration restored
delayed type hypersensitivity to recall antigens within 60 days. These preliminary observations suggest that oral HIV-specific
TF administration, in association with antiviral drugs, is well tolerated and seems beneficial to AIDS patients, thus warranting
further investigation. 相似文献
819.
820.
A rapid three-step DAPI technique is proposed for detecting meiotic stages and sperm head evolution in yolky, fertilized stick insect eggs, which were difficult to analyze with other methods. Fixed eggs were freed from chorionic envelopes and stained directly in DAPI/PBS solution. After rinsing, eggs were singly squashed in a drop of mounting buffer and examined under a microscope with incident fluorescent illumination. The method was almost uniformly successful, and direct observation of nuclear structures, coupled with fluorometry, allowed easy recognition of bivalents, diads, pronuclei and their DNA content. The DAPI method proposed here appears particularly helpful for investigating unusual reproductive modes in eggs with large amounts of yolk. 相似文献