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1.
The degree of intergradation between two species of Sulawesi macaques,Macaca tonkeana andM. hecki, was studied by examining the diagnostic external characteristics of more than 100 monkeys kept as pets by natives. Two possible
hybrid monkeys were found and both originated from the borderland between the two species, located in the most proximal region
of the northern peninsula of Sulawesi. The previously postulated wide area of integradation between the two species at the
possible contact zone was, however, not recognized, and typical examples oftonkeana orhecki were found to be present on the two sides of a narrow “hybrid” zone which was defined by direct observations. Furthermore,
despite considerable individual variations, we were able to allocate most monkeys to one or other of the species. Each of
ten external characteristics of the members of both species more or less encompassed the individual variations, but may undergo
changes with the development of the monkeys. The mechanisms of reproduction of hybrid monkeys and the maintenance of differences
between the species are discussed. 相似文献
2.
Ulviye Acar Çevik Ismail Celik Ufuk İnce Zahra Maryam Iqrar Ahmad Harun Patel Yusuf Özkay Zafer Asım Kaplancıklı 《化学与生物多样性》2023,20(3):e202201146
In this work, the synthesis, characterization, and biological activities of a new series of 1,3,4-thiadiazole derivatives were investigated. The structures of final compounds were identified using 1H-NMR, 13C-NMR, elemental analysis, and HRMS. All the new synthesized compounds were then screened for their antimicrobial activity against four types of pathogenic bacteria and one fungal strain, by application of the MIC assays, using Ampicilin, Gentamycin, Vancomycin, and Fluconazole as standards. Among the compounds, the MIC values of 4 and 8 μg/mL of the compounds 3f and 3g , respectively, are remarkable and indicate that these compounds are good candidates for antifungal activity. The docking experiments were used to identify the binding forms of produced ligands with sterol 14-demethylase to acquire insight into relevant proteins. The MD performed about 100 ns simulations to validate selected compounds’ theoretical studies. Finally, using density functional theory (DFT) to predict reactivity, the chemical characteristics and quantum factors of synthesized compounds were computed. These results were then correlated with the experimental data. Furthermore, computational estimation was performed to predict the ADME properties of the most active compound 3f . 相似文献
3.
The Sea of Marmara, an intercontinental basin with shallow and narrowstraits, connects the Black and Mediterranean Seas. Data
obtained during1991–1996 have permitted the determination of the elementalcomposition of seston in the euphotic zone and the
N:P ratio of thesubhalocline waters of the Marmara Sea. Since primary production is alwayslimited to the less saline upper
layer (15–20 m), of the Marmara Sea,the subhalocline waters of Mediteranean origin are always rich in nutrients(NO3 + NO2 = 8–10 μm, PO4 = 0.8–1.2 μm) but depleted in dissolvedoxygen (30–50 μm) throughout the basin, yielding an -O_2 : N : P ratio of 178 : 9 : 1. Pollution of the surfacewaters since the 60s has modified the subhalocline nutrient chemistryslightly.
In the euphotic zone, the N : P ratio of the seston changes from5.9 to 9.5 between the less and more productive periods. Though
the biologyof the Marmara has changed significantly during the previous two decades,the close relationship observed between
the elemental composition of thesurface seston and the NO3 : PO4 ratio of thesubhalocline waters strongly suggests that during the whole year primaryproduction throughout the basin and POM
export to the lower layer remainnitrogen-limited. This suggestion needs to be confirmed by bio-assays,biological studies and
sediment trap data from the upper subhaloclinedepths. Nonetheless, the counterflows in the Marmara basin possessrelatively
low N : P ratios in both dissolved and particulate nutrients andextend as far as the adjacent seas.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
4.
C Polat 《Acta anatomica》1980,108(4):443-445
Circadian variation in the structure of mast cells has been demonstrated histologically. At 11.00 h the number of mast cells was increased and at 03.00 h it was significantly decreased (p less than 0.01). Morphological analysis has also supported this phenomenon. 相似文献
5.
Parasitism of plants by other plants provides an exceptional opportunity for investigating correlative nutritional relationships.
Because of lacking a usual plant-root sytem capable of active uptake, the best correlation for predicting the concentrations
of elements in parasitic plants is often those in the host plants. This study, therefore, mainly focuses on determination
of i) mineral nutrient partitioning between hemi-parasitic white berry mistletoe (Viscum album L. subsp. album) and four of its deciduous hosts growing in different habitats namely wetland and semi-arid and ii) effects of these habitat
types on nutrient absorption. During the research, leaf samples of both hemi-parasites and their host plants were chemically
analysed, mistletoes on each host plants were counted and the results were considered statistically. Concentrations of some
elements (N, P, K, Na, S, Cu, Zn) were higher in mistletoe whereas some others (Ca, Mg, Fe, Mn and B) were higher in the hosts
(p< 0.05). Habitat type was also determined to be effective in host-parasite systems. Revealing information about nutritional
interactions between multi-host hemi-parasites and their host plants is a useful tool to understand their functions in ecosystems,
population-community dynamics and their co-evolution process. 相似文献
6.
Nehir Kaymak Kirk O. Winemiller Senol Akin Zekeriya Altuner Fatih Polat Tarik Dal 《Hydrobiologia》2015,753(1):131-147
7.
Che Mat Mohd Firdaus Mohamad Hanif Ezanee Azlina Abdul Murad Nor Azian Ibrahim Kamariah Harun Roslan Jamal Rahman 《Molecular biology reports》2021,48(2):1493-1503
Molecular Biology Reports - Despite the advancements in primary brain tumour diagnoses and treatments, the mortality rate remains high, particularly in glioblastoma (GBM). Chemoresistance,... 相似文献
8.
Cheng-Siang Lee Nur Aishah Mohd Taib Ali Ashrafzadeh Farhana Fadzli Faizah Harun Kartini Rahmat See Mee Hoong Puteri Shafinaz Abdul-Rahman Onn Haji Hashim 《PloS one》2016,11(2)
Heavily glycosylated mucin glycopeptides such as CA 27.29 and CA 15–3 are currently being used as biomarkers for detection and monitoring of breast cancer. However, they are not well detected at the early stages of the cancer. In the present study, perchloric acid (PCA) was used to enhance detection of mucin-type O-glycosylated proteins in the serum in an attempt to identify new biomarkers for early stage breast cancer. Sensitivity and specificity of an earlier developed sandwich enzyme-linked lectin assay were significantly improved with the use of serum PCA isolates. When a pilot case-control study was performed using the serum PCA isolates of normal participants (n = 105) and patients with stage 0 (n = 31) and stage I (n = 48) breast cancer, higher levels of total O-glycosylated proteins in sera of both groups of early stage breast cancer patients compared to the normal control women were demonstrated. Further analysis by gel-based proteomics detected significant inverse altered abundance of proteoglycan 4 and plasma protease C1 inhibitor in both the early stages of breast cancer patients compared to the controls. Our data suggests that the ratio of serum proteoglycan 4 to protease C1 inhibitor may be used for screening of early breast cancer although this requires further validation in clinically representative populations. 相似文献
9.
Süleyman Yılmaz Yusuf Akbaba Bünyamin Özgeriş Leyla Polat Köse 《Journal of enzyme inhibition and medicinal chemistry》2016,31(6):1484-1491
A series of carbamate derivatives were synthesized and their carbonic anhydrase I and II isoenzymes and acetylcholinesterase enzyme (AChE) inhibitory effects were investigated. All carbamates were synthesized from the corresponding carboxylic acids via the Curtius reactions of the acids with diphenyl phosphoryl azide followed by addition of benzyl alcohol. The carbamates were determined to be very good inhibitors against for AChE and hCA I, and II isoenzymes. AChE inhibition was determined in the range 0.209–0.291?nM. On the other hand, tacrine, which is used in the treatment of Alzheimer’s disease possessed lower inhibition effect (Ki: 0.398?nM). Also, hCA I and II isoenzymes were effectively inhibited by the carbamates, with inhibition constants (Ki) in the range of 4.49–5.61?nM for hCA I, and 4.94–7.66?nM for hCA II, respectively. Acetazolamide, which was clinically used carbonic anhydrase (CA) inhibitor demonstrated Ki values of 281.33?nM for hCA I and 9.07?nM for hCA II. The results clearly showed that AChE and both CA isoenzymes were effectively inhibited by carbamates at the low nanomolar levels. 相似文献
10.
Abdul Rahman Amirah Mokhtar Norfilza Mohd Harun Roslan Jamal Rahman Wan Ngah Wan Zurinah 《Journal of physiology and biochemistry》2019,75(4):499-517
Journal of Physiology and Biochemistry - Gamma-tocotrienol (GTT) and hydroxychavicol (HC) exhibit anticancer activity in glioma cancer cells, where the combination of GTT + HC was shown to be more... 相似文献