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101.
102.
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   
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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   
105.
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   
106.
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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S-腺苷甲硫氨酸(S-adenosyl-l-methionine, SAM)广泛存在于生物体内,主要参与生物体内的转甲基过程、转硫过程及转氨丙基过程,具有重要的生理功能,其生产备受重视。目前SAM生产的研究主要集中于微生物发酵法,该方法与化学合成法和酶催化法相比,成本较低且更容易实现工业化生产。随着需求量的迅速增加,通过菌种改良提高SAM产量备受关注。当前SAM生产菌种改良的主要策略包括常规育种和代谢工程。本文综述了提高微生物生产SAM能力的近期研究进展并探讨了SAM生产中的瓶颈问题及解决方法,以期为进一步提高SAM产量提供思路。  相似文献   
109.
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   
110.
The current study was designed to evaluate the antioxidant, anticancer and antimicrobial activities of silver nanoparticles (AgNPs) biosynthesized by Spirulina platensis extract. The biosynthesized silver nanoparticles were characterized using Fourier transform infrared (FT-IR) analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) analysis. The antioxidant activity of the biosynthesized AgNPs were determined via DPPH radical scavenging assay while its anticancer activity was determined using the MTT assay. The antimicrobial activity of the biosynthesized AgNPs were analyzed by disc diffusion method. Spirulina platensis acts as a reducing and capping agent. The efficacy of silver nanoparticles (AgNPs) in inhibiting the growth of Gram-negative bacteria, specifically Acetobacter, Klebsiella, Proteus vulgaris, and Pseudomonas aeruginosa, was assessed by the utilisation of the diffusion method. The study aimed to evaluate the efficacy of biosynthesized silver nanoparticles (AgNPs) against many strains of Pseudomonas aeruginosa bacteria. The findings of the study revealed that when administered in doses of 50 μl, 75 μl, and 100 μl, the largest observed zone of inhibition corresponded to measurements of 10.5 mm, 14 mm, and 16 mm, respectively. A zone of inhibition with dimensions of 8 mm, 10.5 mm, and 12 mm was detected during testing against Acetobacter at concentrations of 50 μl, 75 μl, and 100 μl, respectively. The findings also indicate that there is a positive correlation between the concentration of AgNP and the DPPH scavenging ability of silver nanoparticles. The percentage of inhibition observed at concentrations of 500 μg/ml, 400 μg/ml, 300 μg/ml, 200 μg/ml, and 100 μg/ml were recorded as 80±1.98, 61±1.98, 52±1.5, 42±1.99, and 36±1.97, respectively. In addition, it was observed that the silver nanoparticles exhibited the greatest antioxidant activity at a concentration of 500 g/ml, with a measured value of 80.89±1.99. The IC-50 values, representing the inhibitory concentration required to achieve 50 % inhibition, were found to be 8.16, 19.15, 30.14, 41.13, and 63.11 at inhibition levels of 36±1.97, 42±1.99, 52±1.5, 61±1.98, and 80±1.98, respectively.  相似文献   
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