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排序方式: 共有197条查询结果,搜索用时 31 毫秒
31.
32.
Rapamycin-induced insulin resistance is mediated by mTORC2 loss and uncoupled from longevity 总被引:2,自引:0,他引:2
Lamming DW Ye L Katajisto P Goncalves MD Saitoh M Stevens DM Davis JG Salmon AB Richardson A Ahima RS Guertin DA Sabatini DM Baur JA 《Science (New York, N.Y.)》2012,335(6076):1638-1643
Rapamycin, an inhibitor of mechanistic target of rapamycin complex 1 (mTORC1), extends the life spans of yeast, flies, and mice. Calorie restriction, which increases life span and insulin sensitivity, is proposed to function by inhibition of mTORC1, yet paradoxically, chronic administration of rapamycin substantially impairs glucose tolerance and insulin action. We demonstrate that rapamycin disrupted a second mTOR complex, mTORC2, in vivo and that mTORC2 was required for the insulin-mediated suppression of hepatic gluconeogenesis. Further, decreased mTORC1 signaling was sufficient to extend life span independently from changes in glucose homeostasis, as female mice heterozygous for both mTOR and mLST8 exhibited decreased mTORC1 activity and extended life span but had normal glucose tolerance and insulin sensitivity. Thus, mTORC2 disruption is an important mediator of the effects of rapamycin in vivo. 相似文献
33.
As concerns over the negative social and environmental impacts of industrial agriculture become more widespread, efforts to
define and regulate sustainable agriculture have proliferated in the US. Whereas the USDA spearheaded previous efforts, today
such efforts have largely shifted to Tripartite Standards Regimes (TSRs). Using a case study of the Leonardo Academy’s initiative
to develop a US sustainable agriculture standard, this paper examines the standards-development process and efforts by agribusiness
to influence the process. Specifically, we analyze how politics operate in seemingly “depoliticized” TSRs, and how agribusiness
and the USDA use “framing practices” and procedural complaints to influence the standard-development process. We contend that
although governance mechanisms are a potentially powerful tool for advocates of alternative agrifood, their efficacy may be
constrained by science-based requirements, an agribusiness countermovement, and a captured state. 相似文献
34.
35.
Aya Ohnuma-Koyama Toshinori Yoshida Naofumi Takahashi Satoshi Akema Yukiko Takeuchi-Kashimoto Maki Kuwahara Mika Nagaike Kosei Inui Nobuaki Nakashima Takanori Harada 《Journal of toxicologic pathology》2013,26(2):197-201
We report a biphasic malignant mesothelioma in an aged female F344/DuCrlCrlj rat. Macroscopically, multiple pale brown nodules were observed in the abdominal cavity with retention of bloody ascites. Histopathologically, the tumor cells spread over the peritoneum and formed masses on the surface and underlying adipose tissues. The tumor cells dominantly proliferated in a solid, nodular or nest-like pattern with modest amount of fibrillar connective tissues, which contained hyaluronan. The tumor consisted of ovoid, polygonal or spindle-shaped cells that possessed eosinophilic cytoplasms including glycogen; some tumor cells showed a signet-ring-like structure. Multinucleated cells and mitosis were found frequently, and direct invasion to intra-abdominal organs and intravascular metastasis to the liver were observed. Immunohistochemically, keratin and mesothelin were strongly positive in most of tumor cells, while vimentin was mainly positive in spindle-shaped cells. Podoplanin was also positive, particularly in the cell membrane of tumor cells. Electron microscopically, tumor cells showed an intercellular desmosome-like structure, basement membrane and microvillus. We diagnosed the case as a malignant peritoneal mesothelioma with a sarcomatoid growth pattern and signet-ring-like structure. 相似文献
36.
Zeinab Mirzaie Fouladvand Ebrahim Pourjam Natsumi Kanzaki Robin M. Giblin‐Davis Majid Pedram 《Forest Pathology》2019,49(2)
Basilaphelenchus gorganensis n. sp. is described and illustrated from wood and bark of a dead tree from northern Iran. The new species is characterized by female body length (415–559 µm), three‐lined lateral fields, a sclerotized cephalic vestibule and cephalic framework, thin stylet with three elongate backwardly directed knobs, small spherical to oval metacorpus, with small and posteriorly located valve, simple vulva without any flap apparatus, 59‐ to 79‐µm‐long post‐vulval uterine sac, functional rectum and anus and dorsally convex, ventrally concave, usually ventrally bent conical female tail with a sharp tip. Males are common, apparently functional and characterized by well‐curved spicules, three pairs of small caudal papillae and no bursa at tail tip. Molecular phylogenetic inferences using partial sequences of small and large subunit ribosomal RNA genes (SSU and LSU rDNA) from different isolates of the new species revealed it differs from currently sequenced species and belongs to the Tylaphelenchinae clade. 相似文献
37.
Saki Ishimaru Mabrouk Elsabagh Seiichi Saiki Atsushi Haruno Maki Nakamura Hidetada Funo Taketo Obitsu Izuru Shinzato Toshihisa Sugino 《Animal Science Journal》2019,90(8):932-938
Three rumen‐protected lysine (RPL) products (AjiPro®‐L, LysiPEARLTM, and Feedtech Bypass LysineTM: A, B, and C, respectively) were tested for stability in two forage‐based total mixed rations (TMR1, 41.3% dry matter (DM), and TMR2, 49.5% DM) (experiment 1) and for Brix value (experiment 2). In experiment 1, each RPL product (2 g each) and TMR diet (200 g) were mixed and stored in plastic bags at 20°C for 0, 1, 3, 6, 12, 24, and 48 hr. In experiment 2, each RPL product (2 g) was dispensed into ion‐exchanged water (20 ml) and kept at 20°C for 0, 0.5, 1, 3, 6, 12, 24, and 48 hr. At each time point, free lysine (Lys) content and Brix values of extracts were measured, and Lys release (LR, %) was calculated. All RPL products LR% varied with varying diets DM and increased with increasing of time exposed to diets; it was highest in C, followed by B, and then A. Water LR% positively correlated with that from diets and with Brix values of Lys dissociated in water. Our results indicated that Lys dissociation from RPL products is affected by diet DM content. Brix value may be used as a potential marker for RPL protection efficacy. 相似文献
38.
Genetic male sterility is a useful trait in plant breeding, especially in angiosperm crops such as corn, onion and carrot.
We found a male sterile sugi (Cryptomeria japonica D. Don) tree in Toyama, Japan. Pollen of sugi is one of the major causes of pollinosis in Japan. We carried out this research
in an attempt to make clear the characteristics and inheritance of this male sterility. Microsporogenesis of the male sterile
tree proceeded meiosis, however, the microspores collapsed after they were separated from pollen tetrads in locules, resulting
in complete male sterility. Most likely, ethylene evolution was responsible for male sterility expression. Full seed setting
in the male sterile tree indicated normal macrosporogenesis. Seeds obtained from crossing between male sterile and normal
lines showed relatively high level of germination and their seedlings grew vigorously. The somatic chromosome numbers of 241
germinated seeds, derived from the male sterile tree, were mostly 22, euploid. These results indicated that male sterile tree
was different from other similar previously reported trees with low pollen fertility, resulting from triploid or trisomics.
Probably, male sterility in sugi is either nuclear genetic male sterility or cytoplasmic male sterility.
The study was partially supported by Program for Promotion of Basic Research Actives for Innovative Biosciences. 相似文献
39.
Taisei Nagata Mamoru Sameshima Taku Uchikawa Natsumi Osafune Takeshi Kitano 《Fisheries Science》2017,83(2):273-281
Episodes of summer mortality of the Kumamoto oyster Crassostrea sikamea are a major problem for its cultivation. Expression of the heat shock protein 70 (HSP70) is induced by various environmental stresses, including heat. We cloned and sequenced hsp70 complementary DNA from C. sikamea to investigate the relationship between hsp70 expression and heat tolerance in this oyster. Quantitative real-time polymerase chain reaction was performed using gill tissue dissected from oysters before and after heat shock for 1 h. The results showed hsp70 expression was faster and greater in oysters cultured at 20–22 °C than at 10–12 °C, and survival was lower among oysters cultured at 20–22 °C than at 10–12 °C. Moreover, heat tolerance was investigated by a 1-h pre-heat treatment, followed by exposure to heat shock conditions 5 days later. Survival was higher and hsp70 expression was notably lower in oysters that received the pre-heat treatment compared with those that did not. We conclude that a pre-heat treatment of only 1 h may be useful for inducing heat tolerance in C. sikamea, and that a low level of hsp70 expression after heat shock is an important index in selecting for high heat tolerance in these oysters. 相似文献
40.
Atsushi Ajitomi Tetsuya Takushi Atsushi Ooshiro Maki Yamashiro Satoshi Taba 《Journal of General Plant Pathology》2018,84(1):70-72
A panicle blight with sclerotia was found on mango (Mangifera indica L.) in Okinawa Prefecture, Japan, in March 2016. Water-soaked lesions with white mycelia developed on panicles in the flowering stage; softening and decay of panicles was followed by formation of sclerotia. The fungus isolated from these sclerotia was identified as Sclerotinia sclerotiorum based on morphology and analysis of rDNA-ITS sequences. The isolate reproduced the symptoms on mango panicles in an inoculation test and was reisolated from flower stalks. This is the first report of sclerotinia rot (kinkaku-byo in Japanese) on mango caused by S. sclerotiorum in Japan. 相似文献