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排序方式: 共有623条查询结果,搜索用时 31 毫秒
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A MicroRNA signature associated with prognosis and progression in chronic lymphocytic leukemia 总被引:2,自引:0,他引:2
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Katarzyna Socha Katarzyna Klimiuk Sylwia K. Naliwajko Jolanta Soroczyska Anna Pucion-Jakubik Renata Markiewicz-ukowska Jan Kochanowicz 《Nutrients》2021,13(2)
Oxidative stress plays a crucial role in the neurodegenerative process and can impair cognitive functions. In the prevention of Alzheimer’s disease (AD), an adequate consumption of dietary antioxidants may be a major factor. The objective of the study was to estimate selenium (Se), copper (Cu), zinc (Zn), and total antioxidant status (TAS) in the serum of patients with AD in relation to their cognitive functions and dietary habits. A total of 110 patients (aged 54–93 years) with early or moderate AD, as well as 60 healthy people (aged 52–83 years) were studied. The severity of the disease was assessed using the mini-mental state examination (MMSE) scale. Food-frequency questionnaires were implemented to collect the dietary data. The concentrations of Se, Cu and Zn in the sera were determined by the atomic absorption spectrometry method. TAS was estimated spectrophotometrically using ready-made kits (Randox). Significantly lower concentrations of Se, Zn and TAS, and higher Cu:Zn ratio in the serum of patients with AD, compared to healthy people, were observed. A low correlation between the MMSE score and TAS in the serum of AD patients and significantly higher MMSE values in patients with TAS above the reference range were also noted. In patients with serum Cu concentration above the norm, significantly lower MMSE values were found. Selected dietary habits such as the frequency of consumption of various food products had a significant impact on the concentration of the assessed parameters in the serum of people with AD. 相似文献
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Adriana Mika Lukasz P Halinski Tomasz Sledzinski Sylwia Malgorzewicz Paulina Woloszyk Jolanta Dardzinska Alicja Debska-Slizien Michal Chmielewski 《Nutrients》2021,13(3)
Patients with end-stage kidney disease, treated with renal transplantation, are at increased risk of cardio-vascular disease (CVD) and cardio-vascular mortality. They are also characterized by an atherogenic dyslipidemia. Alterations of the fatty acids (FA) profile contribute to increased cardio-vascular risk in the general population. In the current study we test the hypothesis that kidney transplantation is associated with ab-normalities in FA profile. FA profile was analysed by gas chromatography–mass spectrometry in 198 renal transplant recipients, and 48 control subjects. The most profound differences between renal transplant patients and controls were related to the content of branched chain FA, monounsaturated FA, and n-6 polyunsaturated FA, respectively. The FA profile significantly separated the patients from the controls in the principal component analysis (PCA). The abnormalities of FA profile showed a tendency for normalization in long-term kidney recipients, as compared to patients with recent transplants. The n-3 PUFA content demonstrated a strong inverse association with the presence of inflammation. Most profound alterations of the FA profile were observed in patients with impaired graft function (glomerular filtration rate < 45 mL/min). The study demonstrated significant disorders of the FA profile in kidney transplant recipients, that might contribute to cardio-vascular risk in this vulnerable patient population. 相似文献
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Eugen Van Der Zypen Franz Fankhauser Ernst F. Lüscher Sylwia Kwansniewska Ceri England 《Documenta ophthalmologica. Advances in ophthalmology》1992,79(3):221-239
Haemostasis was effected in vessels of melanin-rich (MR: choroid) and melanin-free (MF: mesentery) rabbit tissue irradiated with a cw-Nd: YAG laser. The following parameters were employed: - pulse duration: 200 ms (MR) and 100ms (MF); focal spot diameter: 200 m (MR) and 80 m (MF); pulse energies: 100–250 mJ (MR) and 0.5-1J (MF); irradiances: 1.6–4.0kWcm–2 (MR) and 1–2 × 102kWcm2 (MF). In melanin-rich tissue, laser energy is absorbed principally by melanin granules contained within the stromal melanocytes. The heat generated in these structures radiates into the surrounding tissue where it is dissipated. The damage thus incurred by the endothelium of blood vessels encompassed within this field triggers the haemostatic mechanism whereby blood flow is arrested. This effect is realized by the formation of an occluding plug of platelets, which is stabilized by the deposition of fibrin, particularly in capillaries, and to a lesser degree in larger vessels of the vascular lamina. In melanin-free tissue, haemoglobin serves as the primary site of energy absorption, which is thus shifted from the stroma to the vessel lumen. Irradiation of vessels in such tissue leads to thermocoagulation of plasma proteins and consequent stasis of blood flow. 相似文献
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Pawl RP 《Current review of pain》2000,4(4):259-267
The topic of reflex sympathetic dystrophy (RSD) has generated an increasingly significant volume of medical literature and controversy over the last decade. A search of PubMed, the online site of the National Library of Medicine, for papers on RSD reveals nearly 2200 articles on the topic (using algodystrophy as the search word, wherein RSD references are also included, and more older and European articles are also listed). From 1991 through 1998 inclusive there is an average of nearly 100 articles per year on the topic, which represents more than a third of all the articles referenced since 1965. In the decade of the 1980s, there is an average of 64 articles per year, 74 per year in the last half of the decade and 54 per year in the first half. Prior to the decade of the 1980s, one finds an average of 40 articles per year back to the mid-1960s. The controversy surrounding the disorder centers around the nature of the problem and whether it is a primary organic disorder or a primary psychogenic disorder associated with the accomplishment of some secondary gain. If it is the former, then clearly research should continue to determine the nature and etiology of the malfunctioning organ(s). If, on the other hand, RSD is a psychogenic disorder, then the medical community does well to focus mainly on the peripheral manifestations of the problem. In that instance, therapy should be primarily psychological and cognitive with regard to the secondary gain, and persistent organic treatments are unlikely to improve the condition in general and worsen individual cases. 相似文献
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Turman JE MacDonald AS Pawl KE Bringas P Chandler SH 《The Journal of comparative neurology》2000,427(1):109-123
Trigeminal motoneurons (Mo5) and mesencephalic trigeminal neurons (Me5) are important constituents of the neural circuitry responsible for jaw movements. Non-N-methyl-D-aspartate (NMDA) glutamate receptors are a critical component of the brainstem circuitry responsible for reflex and centrally activated jaw movements; however, little is known about the expression of these receptors in neonatal oral-motor circuitry. Receptor immunohistochemistry using affinity-purified polyclonal antibodies directed against GluR1, GluR2/3/4c, and GluR4, respectively, and a monoclonal antibody directed against the GluR2 subunit, were used in rats at postnatal day (P)1, P3, P5, P10, P19-21, P32-35, and P60 to describe the expression of the alpha-amino-d-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor in Mo5 and Me5 neurons. In Mo5, immunoreactivity was noted for all antibodies throughout the time frame sampled. Neurons in caudal portions of Me5 displayed immunoreactivity to each antibody except at P60 when GluR2 immunoreactivity was absent. Neurons located in rostral Me5 displayed GluR2/3/4c and GluR4 immunoreactivity throughout the time frame, GluR1 immunoreactivity emerged at P3 and a transient expression of GluR2 expression was observed between P10 and P32-35. The lack of labeling of some neurons in both regions, coupled with differences in temporal expression, suggests that there are differences in the AMPA receptor phenotype within and between Mo5 and Me5 during postnatal development. Differences in AMPA subunit composition suggest a complex role for AMPA-mediated glutamatergic neurotransmission in brainstem circuits controlling jaw movements. 相似文献
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Lake Szmaragdowe and Czarnog?owy Reservoir are both characterized by atypical origin as both were formed when quarries were flooded. The geological substrates of the two basins are unique, and they are both highly valued as recreational and tourist destinations. These two basins are among the most interesting in northwestern Poland. Studies of their thermal regimes confirmed that water mass mixing in Lake Szmaragdowe is bradymictic. The waters in the Czarnog?owy Reservoir mix entirely to a depth of 20 m, and this layer is also characterized by bradymixia. Deeper waters do not mix. This indicates that mixing in this basin is of the meromictic type. 相似文献