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101.
Summary The occurrence of cells resembling mammalian Langerhans cells in the avian epidermis was studied by ATPase histochemistry, Ia immunoreactivity and electron microscopy. The existence of MHC class II antigen-(Ia) expressing, ATPase-positive dendritic cells, which are ultrastructurally similar to mammalian Langerhans cells except for the absence of Birbeck granules, was demonstrated. These cells may be a basic component of the immune system of birds. 相似文献
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E. J. Breslau-Siderius J. Th. Wijnen J. G. Dauwerse J. M. de Pater F. A. Beemer P. Meera Khan 《Human genetics》1993,92(5):481-485
A de novo duplication of the proximal part of the long arms of chromosome 5 was found in a male born with craniostenosis, ear tags and kidney dysplasia. The nature of the chromosomal aberration was defined by fluorescence in situ hybridization and the orgin of the duplication was traced by polymorphic DNA markers. A comparison is made with the published cases showing similar duplications in the long arm of chromosome 5. 相似文献
104.
Seyede Saba Hosseini Seyed Omar Ebrahimi Maryam Haji Ghasem Kashani Somayeh Reiisi 《Cell biology international》2023,47(1):98-109
Naturally-derived drugs have drawn much attention in recent decades. Efficiency, lower toxicity, and economic reasons are some of their advantages that justify this broad range of administration for different diseases, including cancer. If we can find a specific combination that boosts the effects of their single therapy, leading to synergism effect, increased efficiency, and decreased toxicity, they can act even better. Quercetin and fisetin, two well-known flavonoids, have been used to fight against various cancers. In this study, we investigated their possible synergism quercetin and fisetin on MCF7, MDA-MB-231, BT549, T47D, and 4T1 breast cancer cell lines. Then the optimum combined dose was used to study their impacts on wound healing abilities and clonogenic properties. The real-time qPCR was used to study the expression of their validated downstream effectors in predicted pathways. A significant synergism effect (p < .01, combination index: <1) was observed for all cell lines. Combination therapy was significantly more effective in colony formation (p < .0001) and wound healing assays (p < .001) compared to single therapies. The expression level of potential effectors was also showed a greater change. In vivo study confirmed the in vitro results and showed how significantly (p < .001) their synergism promotes their singular function in inhibiting cancer progression. The breast cancer mouse models receiving combined therapy lived longer with higher average body weight and smaller tumor sizes. These results exhibit that quercetin and fisetin inhibit cancer cell proliferation, migration and colony formation synergistically, and matrix metalloproteinase signaling and apoptotic pathways are relatively responsible for inhibitory activities. 相似文献
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Aamir Hamid Khan Ling Min Yizan Ma Muhammad Zeeshan Shuangxia Jin Xianlong Zhang 《Plant biotechnology journal》2023,21(4):680-697
Global food security is one of the utmost essential challenges in the 21st century in providing enough food for the growing population while coping with the already stressed environment. High temperature (HT) is one of the main factors affecting plant growth, development and reproduction and causes male sterility in plants. In male reproductive tissues, metabolic changes induced by HT involve carbohydrates, lipids, hormones, epigenetics and reactive oxygen species, leading to male sterility and ultimately reducing yield. Understanding the mechanism and genes involved in these pathways during the HT stress response will provide a new path to improve crops by using molecular breeding and biotechnological approaches. Moreover, this review provides insight into male sterility and integrates this with suggested strategies to enhance crop tolerance under HT stress conditions at the reproductive stage. 相似文献
107.
Mohd Imran Shahzad Ahmed Ahmad Zuhairi Abdullah Jabir Hakami Anis Ahmad Chaudhary Hassan Ahmad Rudayni Salah-Ud-Din Khan Afzal Khan Nosiba Suliman Basher 《Luminescence》2023,38(7):1064-1086
The penicillin derivative amoxicillin (AMX) plays an important role in treating various types of infections caused by bacteria. However, excessive use of AMX may have negative health effects. Therefore, it is of utmost importance to detect and quantify the AMX in pharmaceutical drugs, biological fluids, and environmental samples with high sensitivity. Therefore, this review article provides valuable and up-to-date information on nanostructured material-based optical and electrochemical sensors to detect AMX in various biological and chemical samples. The role of using different nanostructured materials on the performance of important optical sensors such as colorimetric sensors, fluorescence sensors, surface-enhanced Raman scattering sensors, chemiluminescence/electroluminescence sensors, optical immunosensors, optical fibre-based sensors, and several important electrochemical sensors based on different electrode types have been discussed. Moreover, nanocomposites, polymer, and MXenes-based electrochemical sensors have also been discussed, in which such materials are being used to further enhance the sensitivity of these sensors. Furthermore, nanocomposite-based photo-electrochemical sensors and the market availability of biosensors including AMX have also been discussed briefly. Finally, the conclusion, challenges, and future perspectives of the above-mentioned sensing techniques for AMX detection are presented. 相似文献
108.
A responsive spectrofluorometric method was developed for the determination of sitagliptin phosphate using l -tyrosine as a fluorescence probe. The fluorescence intensity of l -tyrosine was quenched with sitagliptin phosphate. The fluorescence intensity was recorded at 307 nm using a 272 nm excitation wavelength. The calibration plot between fluorescence intensity and the concentration of drug was linear in the range of 0.1 to 2.0 mM with a good correlation value of 0.997. The limit of detection and quantification were established to be 3.7 × 10−4 and 1.23 × 10−3 mM, respectively. Commonly used excipients did not interfere with sitagliptin phosphate measurement. The proposed method was used to measure the sitagliptin phosphate in its standard type, dosage form, and biological samples. The percent recovery ranged from 97.41–103.36%. The static quenching was shown to be responsible for quenching as indicated by the Stern–Volmer plot. The method was validated using ICH guidelines and profitably applied for the content uniformity test, resulting in a high percent recovery and small relative standard deviation. The proposed approach is effortless, susceptible, selective, economic, and provides a high precision and accuracy, and can be used to determine sitagliptin phosphate in the pharmaceutical industry. 相似文献
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Measurements were made of fecal pellets for captive brow-antlered deer (Cervus eldi eldi) from different age and sex classes. Pellet measurements increased linearly with increases in age, except for length and width measurements in males. Differences in dimensions were statistically significant between sexes and among some age classes. This procedure may be useful in differentiating between the sexes, and to some extent between ages, of wild-living individuals. © 1993 Wiley-Liss, Inc. 相似文献