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111.
Ishtiaq Mahmud Mineko Asanagi Yoshiaki Miura 《Biochemical and biophysical research communications》1980,93(3):661-667
In rats, feeding protein free diet for 4 days followed by starvation and then high protein diet induced a biphasic ornithine decarboxylase (EC 4.1.1.17) activity, prolonged thymidine kinase (EC 2.7.1.21) activity and DNA synthesis. In contrast feeding a diet containing casein-equivalent amino acid mixture induced a monophasic ornithine decarboxylase activity, short-lived thymidine kinase activity and DNA synthesis. To maintain prolonged thymidine kinase activity and DNA synthesis high protein diet must be given in the early part of the prereplicative period. 相似文献
112.
Allozyme variation in a population of the common mussel Mytilus edulis in Mumbles, South Wales, has been studied by starch gel electrophoresis. On the basis of data obtained for 34 loci, we estimate the proportion of loci polymorphic to be 30%. Using only the 29 loci for which individual genotypes can be accurately typed, the average heterozygosity is estimated to be 9.5 +/- 3.6%. The calculated expected average heterozygosity based on Hardy-Weinberg expectations is identical with the observed value. Allele frequency data at six polymorphic loci are given for several other British populations. There is no significant geographic heterogeneity. The results are discussed in relation to genetic adaptive strategies and are shown to be inconsistent with the predictions of the neutral hypothesis. 相似文献
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114.
M. A. Parvez Mahmud Nazmul Huda Shahjadi Hisan Farjana Mohsen Asadnia Candace Lang 《Liver Transplantation》2018,8(2)
Implantable medical devices (IMDs) have experienced a rapid progress in recent years to the advancement of state‐of‐the‐art medical practices. However, the majority of this equipment requires external power sources like batteries to operate, which may restrict their application for in vivo situations. Furthermore, these external batteries of the IMDs need to be changed at times by surgical processes once expired, causing bodily and psychological annoyance to patients and rising healthcare financial burdens. Currently, harvesting biomechanical energy in vivo is considered as one of the most crucial energy‐based technologies to ensure sustainable operation of implanted medical devices. This review aims to highlight recent improvements in implantable triboelectric nanogenerators (iTENG) and implantable piezoelectric nanogenerators (iPENG) to drive self‐powered, wireless healthcare systems. Furthermore, their potential applications in cardiac monitoring, pacemaker energizing, nerve‐cell stimulating, orthodontic treatment and real‐time biomedical monitoring by scavenging the biomechanical power within the human body, such as heart beating, blood flowing, breathing, muscle stretching and continuous vibration of the lung are summarized and presented. Finally, a few crucial problems which significantly affect the output performance of iTENGs and iPENGs under in vivo environments are addressed. 相似文献
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116.
Organic products are derived from the organic production system, following organic agricultural cultivation standards, and processing schedules must be identified by an independent certificate authority. The main characteristic of the organic agricultural production system is that all artificial synthetic materials such as pesticides, fertilizers, growth regulators, feed additives, and gene engineering products are not allowed to use. However, there is much debate on organic production quality and health safety issues in academic circles. Some people believe that there is a “Three Cannot” problem with organic production, that is, organic products “cannot be distinguished, cannot be tasted and cannot be measured” compared to common ones. To objectively reflect the differences in nutritional quality and food safety between organic and conventional products, we combined extensive literatures with our research data and have reported some advances in the sensory quality, nutritional value, and safety of the two types of products. The results showed that organic products tasted better; the percentage of leanness was higher, and the products tasted much tender. The dry matter content of most organic crops was about 7–20% higher than that of conventional foods, and enriched vitamin C, anthocyanins, isoflavones, carotenoids, and other phenolic compounds and more elements such as P, Fe, and Mg and trace elements such as Zn, Cu, and Cr were verified in organic crops. Organic animal products contain more beneficial polyunsaturated fatty acids; the nitrate content in organic fruits and vegetables was 20–50% of that in normal fruits. No pesticide residues and less heavy metals were found in the organic products. Our investigation showed that there were obvious differences in quality and safety between the products that originated from organic agriculture systems and conventional alternatives. This conclusion can provide an important theoretical basis for the healthy development of the organic industry. 相似文献
117.
N Mahmud N Kusuda S Ichinose Y Gyotoku H Nakajima T Ishimaru T Yamabe 《Acta cytologica》1992,36(4):514-516
Vulvar involvement by endometriosis is extremely rare. A patient presented with a vulvar tumor and was diagnosed on needle aspiration biopsy and subsequently on histopathology as having endometriosis of the vulva. The treatment offered was conservative, local excision of the tumor. The patient was well and free of complaints when last seen in the Outpatient Department, at six months of follow-up. Needle aspiration biopsy as a diagnostic tool in vulvar tumors and the histogenesis of the endometriosis are discussed. 相似文献
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119.
Ponnarasy Ganasen Maksudur Rahman Khan M. Abul Kalam Mohd Sabri Mahmud 《Bioprocess and biosystems engineering》2014,37(11):2353-2359
This paper demonstrates Pseudomonas cepacia lipase catalyzed hydrolysis of p-nitrophenyl palmitate under irradiation of light with wavelengths of 250–750 nm. The reaction follows Michaelis–Menten Kinetics and the light irradiation increases the overall rate of hydrolysis. Using Lineweaver–Burk plot K M and V max values for the reaction in presence of light are found to be 39.07 and 66.67 mM/min/g, respectively; while for the same reaction under dark condition, the values are 7.08 and 10.21 mM/min/g. The linear form of enzyme dependent rate of reaction confirms that no mass-transfer limitations are present and the reaction is a kinetically controlled enzymatic reaction. 相似文献
120.
Andrea Riebler Mirco Menigatti Jenny Z Song Aaron L Statham Clare Stirzaker Nadiya Mahmud Charles A Mein Susan J Clark Mark D Robinson 《Genome biology》2014,15(2):R35
Affinity capture of DNA methylation combined with high-throughput sequencing strikes a good balance between the high cost of whole genome bisulfite sequencing and the low coverage of methylation arrays. We present BayMeth, an empirical Bayes approach that uses a fully methylated control sample to transform observed read counts into regional methylation levels. In our model, inefficient capture can readily be distinguished from low methylation levels. BayMeth improves on existing methods, allows explicit modeling of copy number variation, and offers computationally efficient analytical mean and variance estimators. BayMeth is available in the Repitools Bioconductor package. 相似文献