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101.
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N Imai T Kometani P J Crocker J B Bowdan A Demir L D Dwyer D M Mann T C Vanaman D S Watt 《Bioconjugate chemistry》1990,1(2):138-143
New heterobifunctional cross-linking reagents that possessed a photoactive terminus, an electrophilic terminus, and a linking arm between the two termini that had a radiolabeled, enzymatically cleavable bond were synthesized. In a model study, succinimidyl N-[N'-(4-azidobenzoyl)tyrosyl]-beta-alanate (16A) was coupled to n-butylamine (a Lys surrogate), iodinated, and cleaved with chymotrypsin in the presence of tyrosylamide to afford the desired adduct (N-(N'-(4-azidobenzoyl)-3-iodotyrosyl)tyrosinamide, thereby demonstrating the feasibility of the enzymatic cleavage. In a biochemical study, succinimidyl N-[N'-(3-azido-5-nitrobenzoyl)tyrosyl]-beta-alanate (16C) was coupled to Lys-75 of calmodulin (CaM), and the radioiodinated monoadduct was successfully photo-cross-linked, in a calcium-dependent manner, to the human erythrocyte plasma membrane Ca2+,Mg2(+)-ATPase and to a synthetic fragment (M13) containing the CaM-binding region of myosin light-chain kinase. In the latter case, densitometry readings indicated 20% cross-linking efficiency. 相似文献
104.
Mithat Evecen Ümüt Cirit Kamber Demir Özen Banu Özdaş Muzaffer Taş Sema Birler Serhat Pabuccuoğlu 《Animal reproduction science》2010,117(1-2):160-165
Unlike other domestic animals, in vitro maturation (IVM) of canine oocytes still has limited success. The present study investigated the effects of estrous cycle stage and transport temperature of ovaries on in vitro maturation of canine oocytes. The donor bitches were categorized into three groups based on stage of estrus cycle: follicular (proestrus or estrous), luteal (diestrus) and anestrus. One ovary of each pair collected from 39 mature bitches was transported in Phosphate Buffer Saline (PBS) at 4 °C while the other was transported at 37 °C. A total of 1138 Grade I COCs obtained from all ovaries were grouped and matured in modified synthetic oviduct fluid (mSOF) supplemented with follicle stimulating hormone (FSH), luteinizing hormone (LH), essential and non-essential amino acids at 38.5 °C in a humidified 5% CO2, 5% O2, and 90% N2 atmosphere for 72 h. The nuclear maturation rates were evaluated by aceto–orcein staining.Oocytes harvested from follicular and luteal ovaries have a significantly higher maturation rates (MI + MII) than the oocytes from anestrual ovaries in the 37 °C group (p < 0.05). However, oocytes harvested from anestrual ovaries transported at 4 °C had the highest maturation (MI + MII) rate, and the difference between anestrual and luteal ovary groups was significant (p < 0.05). The oocytes from anestrual ovaries transported at 4 °C have significantly higher maturation rates than those transported at 37 °C (p < 0.0001). However, the transport temperature (37 or 4 °C) did not significantly affect the maturation (MI + MII) rates of oocytes harvested from the luteal (p = 0.61) and follicular (p = 0.48) stage ovaries.It can be concluded from this study that (1) both transport temperature and transport temperature × estrus cycle stage interaction effected the maturation rates, while estrus cycle stage alone did not, and (2) transporting canine ovaries at 4 °C can improve in vitro maturation rates in oocytes harvested from anestrous ovaries. 相似文献
105.
Comparative characteristics are presented of hydrological conditions, toxicological situation (chemical composition by 35
elements and water biotesting), macrozoobenthos, and fish population in a salmon river at the impact zone of volcanic activity
and in a pure tributary flowing in similar natural conditions. It is shown that extremal life conditions for hydrobionts are
formed under the influence of volcanic activity: excess of maximum admissible concentration of injurious substances for water
bodies of fish cultural importance by five elements, turbidity up to 371.5 mg/l, and pH up to 5.3. Mean abundance of macrozoobenthos
and spawning density of salmons on a polluted stretch in comparison with the pure-water tributary is lower by 15 and 20 times,
respectively. In sticklebacks of the genus Pungitius living in the polluted stretch, the part of fish with asymmetry of gill rakers, of rays in pectoral fins, and of lateral
scutes is significantly higher (by 2.5 times), as well as the part of asymmetric characters per specimen (by 3.7 times). 相似文献
106.
Esin Ozkuru Duygu Ates Seda Nemli Semih Erdogmus Nur Karaca Hasan Yilmaz Bulent Yagmur Canan Kartal Muzaffer Tosun Ozgul Ozdestan Semih Otles Abdullah Kahriman Bahattin Tanyolac 《Genomics》2019,111(6):1873-1881
Due to its high nutritional value, chickpea is one of the most important and cost-effective legumes for human diet. Nutrient elements, such as Cu, P, K have numerous essential functions for the human metabolism. In this study, association mapping of loci linked to the seed Cu, P and K concentrations were performed on a population consisting of 107 Cicer reticulatum and 73 Cicer arietinum individuals in four environments (two locations x two years). A total of 121,840 SNPs were genotyped across 180 individuals by GBS analysis. The association mapping between the SNP markers and the seed Cu, P, K concentrations were identified and eight SNPs were found to be significantly associated with variations in three nutrient elements in more than two environments This research suggests that association mapping is a useful methodology for the identification of loci controlling the Cu, P and K uptake in chickpea seeds for further association mapping, molecular breeding, and marker-assisted selection and plant breeding studies and provides a broader understanding of the relationship between the investigated Cicer species and the effects of environmental conditions. 相似文献
107.
The aim of this study was to develop chitosan film containing fucoidan and to investigate its suitability for the treatment
of dermal burns on rabbits. Porous films, thickness between 29.7 and 269.0 μm, were obtained by the solvent dropping method.
Water vapor permeability (3.3–16.6/0.1 g), the swelling (0.67–1.77 g/g), tensile strength (7.1–45.8 N), and bioadhesion (0.076–1.771
mJ/cm2) of the films were determined. The thinnest films were obtained with the lowest chitosan concentration (P<.05). The water absorption capacity of the films sharply increased with the freeze-drying technique. The film having the
thickness of 29.7 μm showed the highest amount of moisture permeability (16.6 g/0.1 g). Higher chitosan concentration significantly
increased tensile strength of the films (P<.05). Using higher concentration of lactic acid made films more elastic and applicable, and these films were selected for
in vivo studies. Seven adult male New Zealand white rabbits were used for the evaluation of the films on superficial dermal
burns. Biopsy samples were taken at 7, 14, and 21 days after wounding, and each wound site was examined macroscopically and
histopathologically. After 7 days treatment, fibroplasia and scar were observed on wounds treated with fucoidan-chitosan film.
The best regenerated dermal papillary formation, best reepithelization, and the fastest closure of wounds were found in the
fucoidan-chitosan film treatment group after 14 days compared with other treatment and control groups. It can be concluded
that fucoidan-chitosan films might be a potential treatment system for dermal burns and that changing formulation variables
can modulate the characterizations of the films.
Published: May 24, 2007 相似文献
108.
During the last two decades, discoveries of new members of actinomycetes and novel metabolites from marine environments have drawn attention to such environments, such as sediment and sponge. For the successful isolation of actinomycetes from marine environments, many factors including the use of enrichment and pre-treatment techniques, and the selection of growth media and antibiotic supplements should be taken into account. High-throughput cultivation is an innovative technique that mimics nature, eliminates undesired, fast-growing bacteria and creates suitable conditions for rare, slow-growing actinomycetes. This review comprehensively evaluates the traditional and innovative techniques and strategies used for the isolation of actinomycetes from marine sponge and sediment samples. 相似文献
109.
110.
Nitric oxide synthases are isoenzymes that catalyse the synthesis of nitric oxide (NO). NO plays both pathological and physiological
roles depending on its rate of synthesis and concentration in cellular source and microenvironment. Apoptosis is an important
biological factor in lymphomas. This study evaluates expression of inducible nitric oxide synthase (iNOS) in human lymphomas
and its relation with apoptosis.
This study comprised 46 cases of B-cell lymphoma. The lymphomas were classified as 3 mantle cell, 5 marginal zone, 4 follicular,
2 Burkitt, 25 diffuse large cell, 2 anaplastic large cell, 3 lymphoblastic, 2 lymphoplasmacytic according to WHO classification
of lymphoid neoplasms. Hematoxylin eosin slides of the cases were reviewed and immunoperoxidase technique was performed iNOS
and Caspase monoclonal antibodies to selected sections of each case. Antigen staining was carried out with iNOS and Caspase
proteins and Ultravision Polyvalent, HRP-AEC kit (Neomarkers-Biogen USA). For the evaluation of iNOS and Caspase, tumor areas
with a high density of expression were chosen. Positive stained cells were counted in 5 different areas at a magnification
×40 by an Olympus B × 51 microscope in each case. The iNOS and Caspase expressions were independently recorded by four pathologists
and the results were averaged.
All of the cases were positive for the iNOS and Caspase. But there is not a statistically important relation between lymphoma
grade and iNOS activity. We could not find a correlation between iNOS and patients age. This study reveals the capacity of
B-cell neoplasms to express iNOS in situ. In conclusion, our study revealed that there is a positive relation between iNOS
expression and apoptosis (p $=$ 0.032 spearman correlation). 相似文献