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排序方式: 共有823条查询结果,搜索用时 15 毫秒
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Hausegger KA; Cragg AH; Lammer J; Lafer M; Fluckiger F; Klein GE; Sternthal MH; Pilger E 《Radiology》1994,190(1):199
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Rosenberg ZS; Jahss MH; Noto AM; Shereff MJ; Cheung Y; Frey CC; Norman A 《Radiology》1988,167(2):489-493
Computed tomography (CT) was performed in 42 patients with 49 clinically suspected tears of the posterior tibial tendon. Twenty-eight of the 49 suspected tears were subsequently surgically explored and repaired. Three patterns of tendon abnormalities were recognized on CT scans: type I-intact, hypertrophied, heterogeneous tendon; type II-attenuated tendon; and type III-absence of a portion of a tendon. Types I and II correlated with partial rupture seen during surgery, and type III correlated with complete rupture of the tendon. CT findings were accurate in 96% of the patients who underwent surgery. In four cases (14%), tendon rupture was seen on CT scans, but the extent of the injury was underestimated and the rupture was misclassified. Reactive periostitis of the distal tibia was seen in 71% of diseased tendons and may represent an important factor in the diagnosis of tendon rupture. 相似文献
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Application of an African Ancestry Index as a Genomic Control Approach in a Brazilian Population 总被引:1,自引:0,他引:1
Ten ancestry informative markers were investigated in 101 coronary artery disease patients and 102 healthy controls from a Southern Brazilian population, in order to determine if stratification occurs in this population. The degree of African admixture detected in this population was estimated to be as high as 6%, but no differences between cases and controls were observed. Using an African Ancestry Index (AAI) that estimates admixture at the individual level it was possible to remove from the samples those individuals with evidence of African admixture. Therefore we have shown that it is possible to control for population stratification by choosing individuals, without the loss of statistical power that occurs with the use of other methods of genomic control. 相似文献
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Subsequent to an initial understanding that estrogen was only stimulatory to folliculogenesis, we have come full circle to the present recognition that many actions of estrogen are inhibitory to follicular function. The development of this interpretation has frequently been associated with the controversial issue o f the likely site o f estrogen action, especially in primates, where much of the evidence has been amassed. The accumulated findings in a variety of species seem to demonstrate clearly that at least part of the atretogenic effect of estrogen is exerted directly on the ovary, apparently by interaction with the nuclear estrogen receptor. Recent observations include identification of messenger RNAs for the estrogen receptor and for creatine kinase in the macaque ovary, and a current focus is to localize messages within specific compartments of the ovary. 相似文献
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Peroneus quartus muscle: MR imaging features 总被引:2,自引:0,他引:2
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C1-esterase inhibitor blocks T lymphocyte proliferation and cytotoxic T lymphocyte generation in vitro 总被引:1,自引:0,他引:1
We have previously shown that activated C1s complement and activated T
cells cleave beta2-microglobulin (beta2m) in vitro leading to the formation
of desLys58 beta2m. This process can specifically be inhibited by
C1-esterase inhibitor (C1-inh). Furthermore we showed that exogenously
added desLys58 beta2m in nanomolar amounts to a one-way allogenic mixed
lymphocyte culture (MLC) increased the endogenous production of IL-2 and
the generation of allo-specific cytotoxic T lymphocytes. C1-inh was
purified from fresh human plasma and added to human or murine MLC and
mitogen-stimulated lymphocyte cultures grown in the presence of
complement-inactivated serum. Read-outs were cell proliferation, lymphokine
production and development of T cell-mediated cytotoxicity. We found that
addition of C1-inh to MLC and mitogen- exposed murine and human lymphocyte
cultures inhibited proliferation, the development of allospecific cytotoxic
activity, and changed the endogenous production of IL-2, IL-4, IL-10, IL-12
and IFN-gamma. These data clearly demonstrate a regulatory function of
C1-inh on T cell- mediated immune functions.
相似文献
10.
Dina Ruano António Macedo Maria Jo?o Soares José Valente Maria Helena Azevedo Carlos Pato Mara Helena Hutz Clarissa S Gama Maria Inês Lobato Paulo Belmonte-de-Abreu Peter Heutink Joana Almeida Palha 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2007,(5):642-646
Several observations point to the involvement of disturbed lipid biology in schizophrenia. Reduced response to niacin flushing test, which involves vasodilatation induced by prostaglandin D2 (PGD2), is among the evidences, together with decreased CSF levels of lipocalin-type prostaglandin D2 synthase (PTGDS), the enzyme responsible for the synthesis of PGD2 in the brain. Since PTGDS is also a carrier for lipophilic molecules such as retinoids and thyroid hormones, altered PTGDS levels might influence both PGD2-mediated signaling, and vitamin A and thyroid hormone availability. To test whether genetic variants of PTGDS are involved in the etiology of schizophrenia, we searched for variants in the coding and regulatory regions of the gene. We identified four previously described polymorphisms. Using two case-control samples from Portugal and Brazil, none of the polymorphisms tested was associated with the disease. In addition, no transmission distortion was observed in an independent parents-offspring sample from the Azorean Islands. Our data do not support the involvement of the PTGDS gene in the etiology of schizophrenia. 相似文献