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1.
Samples of marine pleuston were collected from the sea-surface along considerable sections of the track of Eye of the Wind during its 2-year circumnavigational expedition 'Operation Drake' from November 1978 to October 1980. One hundred and eleven of the tow samples contained insects of the genus Halobates . They were assigned to four oceanic species: H. micans, H. sericeus, H. germanus and H. splendens; two coastal species: H. maculatus, H. princeps, and one undescribed species. Various development stages of the oceanic species were found. The locations, time of collection and surface temperatures where sea-skaters were collected are tabulated. Distributional boundaries and population densities of the oceanic species collected are discussed. 相似文献
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Yan Xue Liu Jia Wu Ke-Xin Yang Nan Pan Li-Ben Song Ying Liu Yang Tang Zhong-Hua 《Journal of Plant Growth Regulation》2022,41(6):2421-2434
Journal of Plant Growth Regulation - Early-spring plants are a special type of plant that complete their life cycle promptly in cold, early spring. Very little effort has been made into researching... 相似文献
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The authors study by means of immunoperoxidase method the pattern of thyroglobulin, triiodothyronine and thyroxine distribution in 58 cases of thyroid disorders: 15 euthyroid goiters, 10 Graves' disease, 7 Hashimoto's thyroiditis, 11 folliculo-papillary carcinomas (6 primary tumors and 5 lymph node metastases), 8 follicular carcinomas, 4 anaplastic carcinomas and 3 medullary carcinomas. Thyroglobulin, triiodothyronine and thyroxine were present in most of the thyroid disorders, excepting anaplastic and medullary carcinomas. Thyroglobulin and thyroxine were localized both in the follicular epithelium and in the colloid, whereas triiodothyronine was present especially in the follicular cells. The thyroid hormones distribution in benign lesions is rather similar. In carcinomas, the pattern of thyroglobulin, triiodothyronine and thyroxine is more heterogeneous, but generally the triiodothyronine distribution is similar to that of thyroglobulin. In some carcinomas, triiodothyronine and thyroxine showed a weak or negative immunostaining. The immunoperoxidase method is a valuable tool in the study of functional disturbances in the thyroid pathology and in the diagnosis of thyroid carcinoma metastases as well. Positive thyroid hormones staining clearly indicates the thyroid origin of metastases. 相似文献
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Hanhan Liu Qiangqiang Jia Gianluca Tettamanti Sheng Li 《Insect biochemistry and molecular biology》2013,43(11):1068-1078
In the fruitfly, Drosophila melanogaster, autophagy and caspase activity function in parallel in the salivary gland during metamorphosis and in a common regulatory hierarchy during oogenesis. Both autophagy and caspase activity progressively increase in the remodeling fat body, and they are induced by a pulse of the molting hormone (20-hydroxyecdysone, 20E) during the larval-prepupal transition. Inhibition of autophagy and/or caspase activity in the remodeling fat body results in 25–40% pupal lethality, depending on the genotypes. Interestingly, a balancing crosstalk occurs between autophagy and caspase activity in this tissue: the inhibition of autophagy induces caspase activity and the inhibition of caspases induces autophagy. The Drosophila remodeling fat body provides an in vivo model for understanding the molecular mechanism of the balancing crosstalk between autophagy and caspase activity, which oppose with each other and are induced by the common stimulus 20E, and blockage of either path reinforces the other path. 相似文献
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Demet Tademir Ayegül Karaküük‐yidoan Mustafa Ulali Tuba Takin‐Tok Emne Eln Oru‐Emre Hasan Bayram 《Chirality》2015,27(2):177-188
A series of new chiral thiosemicarbazones derived from homochiral amines in both enantiomeric forms were synthesized and evaluated for their in vitro antiproliferative activity against A549 (human alveolar adenocarcinoma), MCF‐7 (human breast adenocarcinoma), HeLa (human cervical adenocarcinoma), and HGC‐27 (human stomach carcinoma) cell lines. Some of compounds showed inhibitory activities on the growth of cancer cell lines. Especially, compound 17b exhibited the most potent activity (IC50 4.6 μM) against HGC‐27 as compared with the reference compound, sindaxel (IC50 10.3 μM), and could be used as a lead compound to search new chiral thiosemicarbazone derivatives as antiproliferative agents. Chirality 27:177–188, 2015. © 2014 Wiley Periodicals, Inc. 相似文献