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Arguments are presented that approximately 30 000 cells have to be measured in a single experiment to measure radiobiological parameters in a low-dose survival assay. For this purpose, a fully automated device capable of detecting and recognizing individual live unstained mammalian cells at a rate of 1 cm2/min is required. Specifications of such a system are derived and evidence is presented which suggests that this can best be carried out using a solid-state image sensor in the form of a linear array of photodetectors. The outline of the design and other potential uses of such a device are discussed.  相似文献   
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A new series of functionalized amino acid derivatives N-substituted 1-N-(tert-butoxycarbonyl)-2,2-dimethyl-4-phenyl-5-oxazolidine carboxamide (1-17) and 1-N-substituted-3-amino-2-hydroxy-3-phenylpropane-1-carboxamide (18-34) were synthesized and evaluated for their in vitro cytotoxicity against human cancer cell lines. Compound 6 has shown interesting cytotoxicity (IC50 = 5.67 μm) in ovarian cancer, while compound 10 exhibited promising cytotoxicity in ovarian (IC50 = 6.1 μm) and oral (IC50 = 4.17 μm) cancers. These compounds could be of use in designing new anti-cancer agents.  相似文献   
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Objective

To determine the prevalence of cataract surgery and factors associated with post-surgical visual outcomes in migrant Indians living in Singapore.

Research Design and Methods

We conducted a population-based study in 3,400 Indian immigrants residing in Singapore−the Singapore Indian Eye Study (SINDI). All participants underwent comprehensive medical eye examination and a standardized interview. Post-operative visual impairment (VI) was defined as best-corrected or presenting visual acuity (BCVA or PVA) of 20/60 or worse.

Results

The age- and gender-standardized prevalence of cataract surgery was 9.7% (95% confidence interval [CI]: 8.9%, 10.7%) in Singapore resident Indians. Post-operative VI defined by BCVA occurred in 10.9% eyes (87/795). The main causes of post-operative VI were diabetic retinopathy (20.7%), posterior capsular opacification (18.4%), and age-related macular degeneration (12.6%). Undercorrected refractive error doubled the prevalence of post-operative VI when PVA was used.

Conclusions

The rate of cataract surgery is about 10% in Indian residents in Singapore. Socioeconomic variables and migration had no significant impact on the prevalence of cataract surgery. Diabetic retinopathy was a major cause of post-operative VI in migrant Indians living in Singapore. Uncorrected postoperative refractive error remains an efficient way to improve vision.  相似文献   
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Radiation-induced heart disease (RIHD) is a long-term side effect of radiotherapy of intrathoracic, chest wall and breast tumors when radiation fields encompass all or part of the heart. Previous studies have shown that pentoxifylline (PTX) in combination with α-tocopherol reduced manifestations of RIHD in rat models of local heart irradiation. The relative contribution of PTX and α-tocopherol to these beneficial effects are not known. This study examined the effects of PTX alone or in combination with tocotrienols, forms of vitamin E with potential potent radiation mitigation properties. Rats received localized X-irradiation of the heart with an image-guided irradiation technique. At 3 months after irradiation rats received oral treatment with vehicle, PTX, or PTX in combination with a tocotrienol-enriched formulation. At 6 months after irradiation, PTX-treated rats showed arrhythmia in 5 out of 14 animals. PTX alone or in combination with tocotrienols did not alter cardiac radiation fibrosis, left ventricular protein expression of the endothelial markers von Willebrand factor and neuregulin-1, or phosphorylation of the signal mediators Akt, Erk1/2, or PKCα. On the other hand, tocotrienols reduced cardiac numbers of mast cells and macrophages, but enhanced the expression of tissue factor. While this new rat model of localized heart irradiation does not support the use of PTX alone, the effects of tocotrienols on chronic manifestations of RIHD deserve further investigation.  相似文献   
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Prasad  Archana  Patel  Preeti  Pandey  Shatrujeet  Niranjan  Abhishek  Misra  Pratibha 《Protoplasma》2020,257(2):561-572
Protoplasma - Growth and production kinetics of three important glycoalkaloids viz. α-solanine, solanidine, and solasodine in two contrasting prickly and prickleless plants of Solanum viarum...  相似文献   
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Summary

20-hydroxyecdysone stimulates protein synthesis in the male accessory reproductive glands of pharate adults of Spodoptera litura both in vivo and in vitro. Juvenile hormone-I has no synergistic effect when given in conjunction with ecdysone in vivo but it inhibits ecdysone-stimulated protein synthesis in vitro.  相似文献   
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