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The interstitial matrix of human carcinomas and sarcomas transplanted to the nude mouse: immunolocalization of some human and murine components 总被引:1,自引:0,他引:1
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Preparation and characterization of envelope membranes from nongreen plastids 总被引:4,自引:3,他引:1
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We have developed a reliable procedure for the purification of envelope membranes from cauliflower (Brassica oleracea L.) bud plastids and sycamore (Acer pseudoplatanus L.) cell amyloplasts. After disruption of purified intact plastids, separation of envelope membranes was achieved by centrifugation on a linear sucrose gradient. A membrane fraction, having a density of 1.122 grams per cubic centimeter and containing carotenoids, was identified as the plastid envelope by the presence of monogalactosyldiacylglycerol synthase. Using antibodies raised against spinach chloroplast envelope polypeptides E24 and E30, we have demonstrated that both the outer and the inner envelope membranes were present in this envelope fraction. The major polypeptide in the envelope fractions from sycamore and cauliflower plastids was identified immunologically as the phosphate translocator. In the envelope membranes from cauliflower and sycamore plastids, the major glycerolipids were monogalactosyldiacylglycerol, digalactosyldiacylglycerol, and phosphatidylcholine. Purified envelope membranes from cauliflower bud plastids and sycamore amyloplasts also contained a galactolipid:galactolipid galactosyltransferase, enzymes for phosphatidic acid and diacylglycerol biosynthesis, acyl-coenzyme A thioesterase, and acyl-coenzyme A synthetase. These results demonstrate that envelope membranes from nongreen plastids present a high level of homology with chloroplasts envelope membranes. 相似文献
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Hiroki Koda Alban Lemasson Chisako Oyakawa Rizaldi Joko Pamungkas Nobuo Masataka 《PloS one》2013,8(8)
Mother-infant vocal interactions play a crucial role in the development of human language. However, comparatively little is known about the maternal role during vocal development in nonhuman primates. Here, we report the first evidence of mother-daughter vocal interactions contributing to vocal development in gibbons, a singing and monogamous ape species. Gibbons are well known for their species-specific duets sung between mates, yet little is known about the role of intergenerational duets in gibbon song development. We observed singing interactions between free-ranging mothers and their sub-adult daughters prior to emigration. Daughters sang simultaneously with their mothers at different rates. First, we observed significant acoustic variation between daughters. Co-singing rates between mother and daughter were negatively correlated with the temporal precision of the song’s synchronization. In addition, songs of daughters who co-sang less with their mothers were acoustically more similar to the maternal song than any other adult female’s song. All variables have been reported to be influenced by social relationships of pairs. Therefore those correlations would be mediated by mother-daughter social relationship, which would be modifiable in daughter’s development. Here we hypothesized that daughters who co-sing less often, well-synchronize, and converge acoustically with the maternal acoustic pattern would be at a more advanced stage of social independence in sub-adult females prior to emigration. Second, we observed acoustic matching between mothers and daughters when co-singing, suggesting short-term vocal flexibility. Third, we found that mothers adjusted songs to a more stereotyped pattern when co-singing than when singing alone. This vocal adjustment was stronger for mothers with daughters who co-sang less. These results indicate the presence of socially mediated vocal flexibility in gibbon sub-adults and adults, and that mother-daughter co-singing interactions may enhance vocal development. More comparative work, notably longitudinal and experimental, is now needed to clarify maternal roles during song development. 相似文献
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Amina Amadou Alban Fabre Gabriela Torres-Mejía Carolina Ortega-Olvera Angélica Angeles-Llerenas Fiona McKenzie Carine Biessy Pierre Hainaut Isabelle Romieu 《PloS one》2013,8(11)
The use of hormonal therapies, including hormonal contraceptives (HC) and postmenopausal hormone replacement therapy (HRT) have been shown to influence breast cancer (BC) risk. However, the variations of these effects among populations and ethnic groups are not completely documented, especially among Hispanic women. We evaluated the association between HC and premenopausal BC risk, and between HRT and postmenopausal BC risk in Mexican women. Data from a Mexican multi-center population-based case–control study ofwomen aged 35 to 69 years were analysed. A total of 1000 cases and 1074 matched controls were recruited between 2004 and 2007. Information on hormonal therapy was collected through a structured questionnaire. Results were analysed using conditional logistic regression models. Overall, HC were used by 422/891 (47.3%) premenopausal women and HRT was used by 220/1117 (19.7%) postmenopausal women. For HC, odds ratios (ORs) for BC were 1.11 (95% confidence interval (CI): 0.82, 1.49) for current users and 1.68 (95% CI: 0.67, 4.21) for ever-users. No clear effect of duration of use was observed. For HRT, the OR for BC was significantly increased in ever users (OR: 1.45; 95% CI: 1.01, 2.08). A non-significant increased risk was observed for combined estrogen/progestin, (OR = 1.85; 95% CI: 0.84, 4.07) whereas no effect was observed for the use of estrogen alone (OR = 1.14; 95% CI: 0.68, 1.91). Our results indicate that, HC had a non-significant effect on the risk of pre-menopausal BC, but suggested that injected contraceptives may slightly increase the risk, whereas HRT had a significant effect on post-menopausal BC in this population. This study provides new information about the effects of HC and HRT on BC risk in a Mexican population, which may be of relevance for the population of Latin America as a whole. 相似文献
6.
Felix Willmund Marta del Alamo Sebastian Pechmann Taotao Chen Véronique Albanèse Eric B. Dammer Junmin Peng Judith Frydman 《Cell》2013,152(1-2):196-209
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7.
Ben Mersey Rebecca S. Jabbour Kyle Brudvik Alban Defleur 《American journal of physical anthropology》2013,152(4):516-529
The hand and foot remains from Moula‐Guercy cave (Ardèche, France) comprise 24 specimens of Eemian age (ca. 120 ka). The specimens include primarily complete elements, which are rare among the Moula‐Guercy postcrania. The hand remains have several characteristic Neanderthal traits including a laterally facing (parasagittally oriented) second metacarpal‐capitate articulation, a short styloid process, a wide proximal articular surface on the third metacarpal, and absolutely expanded apical tuberosities on the distal hand phalanges relative to modern humans. The foot remains include several incomplete elements along with an antimeric pair of naviculars, a medial cuneiform and cuboid, and a single complete element from each of the distal segments (one each: metatarsal, proximal foot phalanx, intermediate foot phalanx, distal foot phalanx). Consistent among the specimens are relatively wide diaphyses for length in the metatarsals and phalanges and large and prominent muscle attachments, both consistent with previously published Neanderthal morphology. The hand and foot collection from Moula‐Guercy is an important dataset for future studies of Neanderthal functional morphology, dexterity, and behavior as it represents a previously undersampled time period for European Neanderthals. Am J Phys Anthropol 152:516–529, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
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Paolo Maiuri Emmanuel Terriac Perrine Paul-Gilloteaux Timothée Vignaud Krista McNally James Onuffer Kurt Thorn Phuong A. Nguyen Nefeli Georgoulia Daniel Soong Asier Jayo Nina Beil Jürgen Beneke Joleen Chooi Hong Lim Chloe Pei-Ying Sim Yeh-Shiu Chu Andrea Jiménez-Dalmaroni Manuel Théry 《Current biology : CB》2013,23(1):97
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