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81.
Ke Zhou Lei Mo Paul Kay Veronica P. Y. Kwok Tiffany N. M. Ip Li Hai Tan 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(22):9974-9978
Linguistic categories have been shown to influence perceptual discrimination, to do so preferentially in the right visual field, to fail to do so when competing demands are made on verbal memory, and to vary with the color-term boundaries of different languages. However, because there are strong commonalities across languages in the placement of color-term boundaries, the question remains open whether observed categorical perception for color can be entirely a result of learned categories or may rely to some degree on innate ones. We show here that lateralized color categorical perception can be entirely the result of learned categories. In a visual search task, reaction times to targets were faster in the right than the left visual field when the target and distractor colors, initially sharing the same linguistic term (e.g., “blue”), became between-category colors after training (i.e., when two different shades of blue had each acquired a new name). A control group, whose conditions exactly matched those of the experimental group except that no new categories were introduced, did not show this effect, establishing that the effect was not dependent on increased familiarity with either the color stimuli or the task. The present results show beyond question that lateralized categorical perception of color can reflect strictly learned color categories, even artificially learned categories that violate both universal tendencies in color naming and the categorization pattern of the language of the subject. 相似文献
82.
We have tested a panel of four monoclonal antibodies to the T cell receptor (TCR) gamma/delta heterodimer (delta TCS-1, TS-8, TCR delta-1, anti- C gamma m 1) in pregnant and non-pregnant uteri. The TCR gamma/delta complex was not detected on stromal lymphocytes, but was localized in the cytoplasm of the endometrial glandular epithelium from most pregnant uteri. These antibodies also reacted with endometrial glandular epithelium in a majority of non-pregnant uteri; the reactivity was more consistent in secretory phase glands than that in the proliferative phase of menstrual cycle. However, three different monoclonal antibodies to CD3 (OKT3, leu 4, UCHT-1) failed to show any reactivity, suggesting that the presence of the TCR gamma/delta complex was not associated with CD3 complex. The TCR gamma/delta-positive glandular epithelial cells did not react with two monoclonal antibodies to the TCR alpha/beta complex, and they were also CD4- and CD8-negative. Together with the loss of the class 1 MHC antigens from these endometrial glandular epithelial cells in early pregnancy, these data suggest that these TCR gamma/delta-bearing endometrial glandular cells may undergo phenotypic alterations under local regulation of gene expression. 相似文献
83.
Cancer chemoprevention by aliphatic selenocyanates: effect of chain length on inhibition of mammary tumors and DMBA adducts 总被引:1,自引:0,他引:1
The objective of this study was to examine the anticarcino-genicactivity of a series of aliphatic selenocyanates with increasinglength of the carbon side chain, CH3(CH2)nSeCN,in which n = 0, 2, 4 or 6. Their ability to prevent mammarycancer was evaluated during the initiation phase using the rat7,12-dimethyl-benz[a]anthracene (DMBA) model. Each compoundwas added to the diet at a final concentration of 2 p.p.m. Seand was given from 2 weeks before to 1 week after DMBA administration.Analysis of the tumor data suggested the following order ofchemopreventive potency for this series of aliphatic selenocyanates:heptyl 相似文献
84.
Wang AY Sea MM Ip R Law MC Chow KM Lui SF Li PK Woo J 《The American journal of clinical nutrition》2002,76(3):569-576
BACKGROUND: Dialysis patients are at risk of vitamin and mineral deficiencies, not only because of losses during chronic hemodialysis or peritoneal dialysis but also because of low intakes. OBJECTIVE: The objective was to determine the importance of urea clearance (calculated as K(t)/V) and residual renal function (RRF) in predicting micronutrient intakes in a large cohort of patients receiving continuous ambulatory peritoneal dialysis (CAPD). DESIGN: We conducted a survey of dietary intakes in 242 CAPD patients and divided them into 3 groups according to their weekly urea clearance and RRF: WD group (n = 84), a urea clearance >/= 1.7 and a glomerular filtration rate (GFR) >/= 1 mL x min(-1) x 1.73 m(-2); DD group (n = 71), a urea clearance >/= 1.7 and a GFR < 1 mL x min(-1) x 1.73 m(-2); and ID group (n = 87), a urea clearance < 1.7. RESULTS: Most of the patients had intakes of water-soluble vitamins and minerals that were lower than the recommended dietary allowance; most intakes were significantly higher in the WD group than in the DD and ID groups, except those of niacin and calcium. After age, sex, body weight, and the presence of diabetes were controlled for, total weekly urea clearance and the GFR (but not peritoneal dialysis urea clearance) were significantly associated with intakes of vitamins A and C, the B vitamins, and minerals (calcium, phosphate, iron, and zinc). Low intakes of vitamins and minerals with low RRF and urea clearance were the result of reduced overall food intakes, except for thiamine, vitamin B-6, and folic acid, which were deficient in the diet. CONCLUSIONS: Supplementation with most water-soluble vitamins and minerals, including iron and zinc, should be considered in CAPD patients, especially those with low RRF and low urea clearance. The optimal dose needs to be determined. 相似文献
85.
86.
A new method of functional tendon transfer for the dysfunction of extensor hallucis longus 总被引:3,自引:0,他引:3
Leung YF Ip SP Chung OM 《Foot & ankle international / American Orthopaedic Foot and Ankle Society [and] Swiss Foot and Ankle Society》2002,23(12):1124-1125
A surgical technique of functional tendon transfer for the treatment of extensor hallucis longus (EHL) rupture is described. By using the extensor digitorum longus tendon of the second toe, the patient regains active dorsiflexion of the big toe and the deformity of the toe is corrected. 相似文献
87.
88.
Michael S. Ip Justin L. Gottlieb Alon Kahana Ingrid U. Scott Michael M. Altaweel Barbara A. Blodi Ronald E. Gangnon Carmen A. Puliafito 王建民 《美国医学会眼科杂志(中文版)》2005,17(2):76-81,87
目的:探讨玻璃体内注射丙酮化曲安奈德用于治疗视网膜中央静脉阻塞(CRVO)引起黄斑水肿的安全性和有效性。方法:在Wisconsin大学和Bascom Palmer眼科研究所.对13例(13只眼)连续的CRVO引起黄斑水肿的患者应用玻璃体内注射丙酮化曲安奈德(4mg)治疗.回顾研究其病历记录。每次玻璃体内注射时应用27G或30G针头通过睫状体平坦部注射。主要结果测量:Snellen视力的变化、黄斑水肿的临床表现、应用光学相干断层扫描仪(OCT)测量中心凹的增厚以及并发症的出现频率。结果:13例患者的平均年龄为67岁(四分位数间距为57—77岁).注射前症状的平均持续时间为8个月(四分位数间距为4—9个月)。患眼在初诊时的平均视力为20/500.在6个月随诊检查时的平均视力为20/1踟。所有13例患者都完成了6个月的随诊检查。非缺血型CRVO患眼(n=5)的视力有显著的提高.而缺血型CRVO患眼(n=8)没有显著的视力提高。患者没有出现视力下降。初诊时OCT测量的平均中心凹厚度为590μm(视网膜增厚=416μm)。12例患者在1个月随诊检查时OCT测量的平均中心凹厚度为212pm(视网膜增厚=38μm)。13例患者在3个月随诊检查时OCT测量的平均中心凹厚度为193μm(视网膜增厚=19μm)。在3和6个月随诊检查之间.4例患者的黄斑水肿复发.其中3例患者再次接受了曲安奈德的注射。这3例患者中的2例经过再次治疗视力提高。在6个月随诊检查时.13例患者OCT测量的平均中心凹厚度为281μm(视网膜增厚=107μm)。没有发生视网膜脱离或眼内炎等并发症。1例患者出现了眼压的升高.应用2种房水生成抑制剂治疗得以控制。结论:在部分CRVO引起黄斑水肿的患者中.玻璃体内注射曲安奈德可能是一种有效的治疗方法。与缺血型CRVO患者相比.非缺血型CRVO患者可以获得更令人满意的效果。部分患者可能需要重复治疗。在本组患者中未发现严重的并发症。 相似文献
89.
Meng JJ Lowrie DJ Sun H Dorsey E Pelton PD Bashour AM Groden J Ratner N Ip W 《Journal of neuroscience research》2000,62(4):491-502
The product of the neurofibromatosis type II (NF2) tumor suppressor gene, merlin, is closely related to the ezrin-radixin-moesin (ERM) family, a group of proteins believed to link the cytoskeleton to the plasma membrane. Mutation in the NF2 locus is associated with Schwann cell tumors (schwannomas). The two predominant merlin isoforms, I and II, differ only in the carboxy-terminal 16 residues and only isoform I is anti-proliferative. Merlin lacks an actin-binding domain conserved among ezrin, radixin and moesin. Because merlin, ezrin and moesin are co-expressed in Schwann cells, and all homodimerize, we have examined whether merlin and ezrin dimerize with one another. We found by immunoprecipitation and yeast two-hybrid assays that both merlin isoforms interact with ezrin. The interaction occurs in a head-to-tail orientation, with the amino-terminal half of one protein interacting with the carboxy-terminal half of the other. The two merlin isoforms behave differently in their interaction with ezrin. Isoform I binds only ezrin whose carboxy-terminus is exposed, whereas isoform II binds ezrin regardless of whether ezrin is in the open or closed conformation. The heterodimerization of merlin is a much stronger interaction than the interaction between either merlin isoform and ezrin, and can inhibit merlin-ezrin binding. This suggests that, in vivo, merlin dimerization could regulate merlin-ERM protein interaction, and could thus indirectly regulate other interactions involving ERM proteins. 相似文献
90.