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1.
乳腺管状小叶癌(Tubulolobular carcinoma,TLC)最初是被作为小叶癌的管状变型。作者总结了27例TLC的组织学、免疫表型和临床特征,并与纯小管癌和经典型小叶癌进行了比较。此组患者年龄43-79岁(中位年龄60岁)。1例双侧乳腺受累,5例病变为多灶性。肿瘤直径0.5-2.5cm,色灰褐,质硬。组织学观察:TLC的肿瘤细胞形成管状和条索状两种结构模式并相互混杂,且两者比例相当(统称为管状小叶模式)。 相似文献
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Vaughn W. Barry Meghan Baruth Michael W. Beets J. Larry Durstine Jihong Liu Steven N. Blair 《Progress in cardiovascular diseases》2014
The purpose of this study was to quantify the joint association of cardiorespiratory fitness (CRF) and weight status on mortality from all causes using meta-analytical methodology. Studies were included if they were (1) prospective, (2) objectively measured CRF and body mass index (BMI), and (3) jointly assessed CRF and BMI with all-cause mortality. Ten articles were included in the final analysis. Pooled hazard ratios were assessed for each comparison group (i.e. normal weight-unfit, overweight-unfit and -fit, and obese-unfit and -fit) using a random-effects model. Compared to normal weight-fit individuals, unfit individuals had twice the risk of mortality regardless of BMI. Overweight and obese-fit individuals had similar mortality risks as normal weight-fit individuals. Furthermore, the obesity paradox may not influence fit individuals. Researchers, clinicians, and public health officials should focus on physical activity and fitness-based interventions rather than weight-loss driven approaches to reduce mortality risk. 相似文献
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Sara Van Damme Nathan De Fruyt Jan Watteyne Signe Kenis Katleen Peymen Liliane Schoofs Isabel Beets 《Journal of neuroendocrinology》2021,33(1)
In an ever‐changing environment, animals have to continuously adapt their behaviour. The ability to learn from experience is crucial for animals to increase their chances of survival. It is therefore not surprising that learning and memory evolved early in evolution and are mediated by conserved molecular mechanisms. A broad range of neuromodulators, in particular monoamines and neuropeptides, have been found to influence learning and memory, although our knowledge on their modulatory functions in learning circuits remains fragmentary. Many neuromodulatory systems are evolutionarily ancient and well‐conserved between vertebrates and invertebrates. Here, we highlight general principles and mechanistic insights concerning the actions of monoamines and neuropeptides in learning circuits that have emerged from invertebrate studies. Diverse neuromodulators have been shown to influence learning and memory in invertebrates, which can have divergent or convergent actions at different spatiotemporal scales. In addition, neuromodulators can regulate learning dependent on internal and external states, such as food and social context. The strong conservation of neuromodulatory systems, the extensive toolkit and the compact learning circuits in invertebrate models make these powerful systems to further deepen our understanding of neuromodulatory pathways involved in learning and memory. 相似文献
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Hematopoietic growth factors not only modulate blood progenitor cell activity but also alter the function of mature phagocytes. Recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF; 1 ng/mL for 60 min) did not stimulate luminol-enhanced chemiluminescence of polymorphonuclear leukocytes (PMNs) in suspension but primed PMN for as much as a 15-fold increase in chemiluminescence in response to f-met- leu-phe (fMLP). Mixed mononuclear leukocytes (monocytes [approximately 20%] and lymphocytes [approximately 80%]; MNL) chemiluminescence was very low even after rhGM-CSF priming, but MNLs added to the PMNs (PMN- MNL) resulted in near doubling of rhGM-CSF-primed PMN fMLP-stimulated chemiluminescence. The enhancing factor(s) from MNLs were inherent rather than induced by the GM-CSF, and purified lymphocytes increased GM-CSF-primed PMN chemiluminescence equal to mixed MNLs. We could not detect cell-free "enhancing factor(s)," but cell-to-cell contact further enhanced rhGM-CSF-primed fMLP-stimulated PMN-MNL oxidative activity by 40%. Polyclonal rabbit anti-tumor necrosis factor (TNF) (but not preimmune serum) decreased both fMLP-stimulated rhGM-CSF- primed PMNs and PMN-MNL chemiluminescence, suggesting that TNF on the PMN surface is enhancing GM-CSF-primed chemiluminescence. GM-CSF priming markedly increased PMN superoxide release (sevenfold), but PMN superoxide release was not further enhanced by the presence of MNLs. Recombinant human granulocyte colony-stimulating factor (rhG-CSF) and interleukin-3 (rhIL-3) displayed much smaller effects on pure PMNs and mixed PMN-MNL chemiluminescence and superoxide release than rhGM-CSF. rhGM-CSF primes PMNs for increased oxidative activity more than rhG-CSF and rhIL-3. Maximal oxidative activity was observed when mixed PMN-MNL were primed with GM-CSF in a cell pellet-promoting cell-to-cell contact. This enhanced activity can be attributed, in part, to both inherent enhancing factor(s) on lymphocytes and PMN-associated TNF induced by GM-CSF. 相似文献
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Matthieu P. Boisgontier Iseult A.M. Beets Jacques Duysens Alice Nieuwboer Ralf T. Krampe Stephan P. Swinnen 《Neuroscience and biobehavioral reviews》2013
Dual-task designs have been used widely to study the degree of automatic and controlled processing involved in postural stability of young and older adults. However, several unexplained discrepancies in the results weaken this literature. To resolve this problem, a careful selection of dual-task studies that met certain methodological criteria are considered with respect to reported interactions of age (young vs. older adults) × task (single vs. dual task) in stable and unstable postural conditions. Our review shows that older adults are able to perform a postural dual task as well as younger adults in stable conditions. However, when the complexity of the postural task is increased by dynamic conditions (surface and surround), performance in postural, concurrent, or both tasks is more affected in older relative to young adults. In light of neuroimaging studies and new conceptual frameworks, these results demonstrate an age-related increase of controlled processing of standing associated with greater intermittent adjustments. 相似文献
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Primitive hematopoietic stem cells differentiate into committed progenitors that are thought to selectively express hematopoietic growth factor receptor(s), thereby acquiring hematopoietic growth factor responsiveness. To assess whether hematopoietic stem cells express hematopoietic growth factor receptors, the progenitor activity of bone marrow (BM) fractions, isolated by expression of receptors for macrophage/monocyte colony-stimulating factor (M-CSF), were examined. Recovery of day-12 spleen colony-forming units (CFU-S) is diminished in both M-CSF receptor-positive (M-CSFR+) and M-CSFR- fractions, indicating antibody inhibition of day-12 CFU-S. Incubation of BM cells with antibody without fractionation inhibits 50% to 60% of day-12 CFU- S. This inhibition is specific (control antibodies have no effect) and reversible by removal of bound antibody at low pH. Incubating BM cells with control or antireceptor antibody does not affect day-8 CFU-S, which are predominantly erythroid. Treating sublethally irradiated mice with antibody inhibits endogenous day-12 CFU-S. These results indicate that some early progenitors express M-CSFRs, and blocking M-CSFRs inhibits the ability of these progenitors to form colonies, possibly because of inactivation caused by prolonged receptor blockade. 相似文献
9.
胰岛素样生长因子Ⅰ与肝纤维化 总被引:1,自引:1,他引:1
胰岛素样生长因子I(IGF-I)是体内普遍存在的多肽,循环系统中IGF-I主要来源于肝脏.在垂体生长激素的调控下,IGF-I对多种细胞如成纤维细胞、成骨细胞、平滑肌细胞等的有丝分裂均有调节作用.目前观点认为肝星状细胞(HSC)活化后可分泌大量胶原纤维,是肝纤维化时细胞外基质的主要来源.实验表明 IGF-I能够促进体外培养HSC增殖、活化并抑制其凋亡.而体内研究发现,肝硬化患者血清IGF-I浓度显著下降,外源性小剂量IGF-I 注射能够改善肝功能,为肝纤维化的治疗提供了新的理念. 相似文献
10.
The color complementation assay (CCA) is a method of allele-specific DNA amplification by which competitive priming and extension of fluorescently labeled oligonucleotide primers determine the color of DNA amplification product. This diagnostic method precludes the need for radioisotopes, electrophoresis, and multiple high-stringency reaction conditions. The multiplicity of mutant globin genes present in Southeast Asians complicates clinical diagnosis and underscores the importance of DNA-based diagnostic methods. We have applied CCA to distinguish beta A and beta E alleles. Competing 15mer primers were a fluorescein-labeled complement to beta A and a rhodamine-labeled complement to beta E, identical except for their central nucleotides. A common unlabeled primer was used to amplify DNA product, the color of which was determined by the perfectly complementary primer. Color photography and spectrofluorometry, as well as a method of black-white photography that we developed to distinguish fluorescein- and rhodamine- labeled DNA, were used to record results. We applied CCA to define the complex genotype of a Thai woman with thalassemia intermedia, 96% HbE, and 4% HbF whose possible genotypes included several permutations of alpha-thalassemia, beta-thalassemia, and beta E genes. zeta-Globin gene mapping of DNA doubly digested with Bg/II and Asp 718 showed the -alpha 3.7/--SEA genotype, and CCA confirmed homozygous beta E/beta E. The CCA is useful for diagnosing the compound hemoglobin genotypes of Southeast Asians and could be applied also to prenatal diagnosis in this population. 相似文献