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排序方式: 共有220条查询结果,搜索用时 31 毫秒
91.
Wang Z Jalali F Sun YH Wang JJ Parker KH Tyberg JV 《American journal of physiology. Heart and circulatory physiology》2005,288(4):H1641-H1651
Two apparently different types of mechanisms have emerged to explain diastolic suction (DS), that property of the left ventricle (LV) that tends to cause it to refill itself during early diastole independent of any force from the left atrium (LA). By means of the first mechanism, DS depends on decreased elastance [e.g., the relaxation time constant (tau)] and, by the second, end-systolic volume (V(LVES)). We used wave-intensity analysis (WIA) to measure the total energy transported by the backward expansion wave (I(W-)) during LV relaxation in an attempt to reconcile these mechanisms. In six anesthetized, open-chest dogs, we measured aortic, LV (P(LV)), LA (P(LA)), and pericardial pressures and LV volume by orthogonal ultrasonic crystals. Mitral velocity was measured by Doppler echocardiography, and aortic velocity was measured by an ultrasonic flow probe. Heart rate was controlled by pacing, V(LVES) by volume loading, and tau by isoproterenol or esmolol administration. I(W-) was found to be inversely related to tau and V(LVES). Our measure of DS, the energy remaining after mitral valve opening, I(W-DS), was also found to be inversely related to tau and V(LVES) and was approximately 10% of the total "aspirating" energy generated by LV relaxation (i.e., I(W-)). The size of the Doppler (early filling) E wave depended on I(W-DS) in addition to I(W+), the energy associated with LA decompression. We conclude that the energy of the backward-going wave generated by the LV during relaxation depends on both the rate at which elastance decreases (i.e., tau) and V(LVES). WIA provides a new approach for assessing DS and reconciles those two previously proposed mechanisms. The E wave depends on DS in addition to LA decompression. 相似文献
92.
Jure Borišek Sara Pintar Mitja Ogrizek Simona Golič Grdadolnik Vesna Hodnik Dušan Turk 《Journal of enzyme inhibition and medicinal chemistry》2018,33(1):1239-1247
Autolysin E (AtlE) is a cell wall degrading enzyme that catalyzes the hydrolysis of the β-1,4-glycosidic bond between the N-acetylglucosamine and N-acetylmuramic acid units of the bacterial peptidoglycan. Using our recently determined crystal structure of AtlE from Staphylococcus aureus and a combination of pharmacophore modeling, similarity search, and molecular docking, a series of (Phenylureido)piperidinyl benzamides were identified as potential binders and surface plasmon resonance (SPR) and saturation-transfer difference (STD) NMR experiments revealed that discovered compounds bind to AtlE in a lower micromolar range. (phenylureido)piperidinyl benzamides are the first reported non-substrate-like compounds that interact with this enzyme and enable further study of the interaction of small molecules with bacterial AtlE as potential inhibitors of this target. 相似文献
93.
Utilizing Waste Cable Wires for High‐Performance Fiber‐Based Hybrid Supercapacitors: An Effective Approach to Electronic‐Waste Management 下载免费PDF全文
In recent years, electronic waste (e‐waste) such as old cable wires, fans, circuit boards, etc., can be often seen in large piles of leftover in dumping yards. Employing these e‐waste sources for energy storage devices not only increases the economic value but also decreases the reliance on fossil fuels. In this context, waste cable wires are utilized to obtain precious copper (Cu) fibers and used as a cost‐effective current collector for the fabrication of fiber‐based hybrid supercapacitor (FHSC). With the braided Cu fibers, forest‐like nickel oxide nanosheet grafted carbon nanotube coupled copper oxide nanowire arrays (NiO NSs@CNTs@CuO NWAs/Cu fibers) are designed via simple wet‐chemical approaches. As a battery‐type material, the forest‐like NiO NSs@CNTs@CuO NWAs/Cu fiber electrode shows superior electrochemical properties including high specific capacity (230.48 mA h g?1) and cycling stability (82.72%) in aqueous alkaline electrolyte. Moreover, a solid‐state FHSC is also fabricated using forest‐like NiO NSs@CNTs@CuO NWAs/Cu fibers as a positive electrode and activated carbon coated carbon fibers as a negative electrode with a gel electrolyte, which also shows a higher energy and power densities of 26.32 W h kg?1 and 1218.33 W kg?1, respectively. The flexible FHSC is further employed as an energy source for various electronic gadgets, demonstrating its suitability for wearable applications. 相似文献
94.
Maryam Karamali Nabiollah Nasiri Naemeh Taghavi Shavazi Mehri Jamilian Fereshteh Bahmani Maryam Tajabadi-Ebrahimi Zatollah Asemi 《Probiotics and antimicrobial proteins》2018,10(3):496-503
Synbiotics are known to exert multiple beneficial effects, including anti-inflammatory and antioxidative actions. This study was designed to evaluate the effects of synbiotic administration on biomarkers of inflammation, oxidative stress, and pregnancy outcomes among gestational diabetic (GDM) women. This randomized, double-blind, placebo-controlled clinical trial was carried out among 60 subjects with GDM who were not on oral hypoglycemic agents. Patients were randomly assigned to consume either one synbiotic capsule containing Lactobacillus acidophilus strain T16 (IBRC-M10785), L. casei strain T2 (IBRC-M10783), and Bifidobacterium bifidum strain T1 (IBRC-M10771) (2 × 109 CFU/g each) plus 800 mg inulin (HPX) (n = 30) or placebo (n = 30) for 6 weeks. Compared with the placebo, synbiotic supplementation significantly decreased serum high-sensitivity C-reactive protein (hs-CRP) (? 1.9 ± 4.2 vs. +1.1 ± 3.5 mg/L, P = 0.004), plasma malondialdehyde (MDA) (? 0.1 ± 0.6 vs. + 0.3 ± 0.7 μmol/L, P = 0.02), and significantly increased total antioxidant capacity (TAC) (+ 70.1 ± 130.9 vs. ? 19.7 ± 124.6 mmol/L, P = 0.009) and total glutathione (GSH) levels (+ 28.7 ± 61.5 vs. ? 14.9 ± 85.3 μmol/L, P = 0.02). Supplementation with synbiotic had a significant decrease in cesarean section rate (16.7 vs. 40.0%, P = 0.04), lower incidence of hyperbilirubinemic newborns (3.3 vs. 30.0%, P = 0.006), and newborns’ hospitalization (3.3 vs. 30.0%, P = 0.006) compared with the placebo. Synbiotic supplementation did not affect plasma nitric oxide (NO) levels and other pregnancy outcomes. Overall, synbiotic supplementation among GDM women for 6 weeks had beneficial effects on serum hs-CRP, plasma TAC, GSH, and MDA; cesarean section; incidence of newborn’s hyperbilirubinemia; and newborns’ hospitalization but did not affect plasma NO levels and other pregnancy outcomes. http://www.irct.ir: www.irct.ir: IRCT201704205623N108 相似文献
95.
Faraneh Afshar Ebrahimi Fatemeh Foroozanfard Esmat Aghadavod Fereshteh Bahmani Zatollah Asemi 《Biological trace element research》2018,184(2):300-307
Magnesium and zinc are known to exert multiple beneficial effects including anti-inflammatory and antioxidant actions. To our knowledge, data on the effects of magnesium and zinc co-supplementation on biomarkers of inflammation and oxidative stress and gene expression related to inflammation in subjects of polycystic ovary syndrome (PCOS) are scarce. This study was conducted to evaluate the effects of magnesium and zinc co-supplementation on biomarkers of inflammation and oxidative stress and gene expression related to inflammation in subjects with PCOS. This randomized double-blind, placebo-controlled trial was conducted among 60 subjects with PCOS diagnosed according to the Rotterdam criteria, aged 18–40 years old. Participants were randomly assigned into two groups to take either 250 mg of magnesium oxide plus 220 mg of zinc sulfate (containing 50 mg zinc) supplements (n?=?30) or placebo (n?=?30) twice a day for 12 weeks. Biomarkers of inflammation and oxidative stress were assessed at baseline and at end of treatment. Gene expression related to inflammatory cytokines was assessed in peripheral blood mononuclear cells (PBMCs) of PCOS women with RT-PCR method. After the 12-week intervention, compared with the placebo, magnesium and zinc co-supplementation significantly decreased serum high-sensitivity C-reactive protein (hs-CRP) (??1.6?±?2.4 vs. +?0.1?±?0.7 mg/L, P?=?0.001) and protein carbonyl (PCO) (??0.14?±?0.28 vs. +?0.02?±?0.07 mmol/mg protein, P?=?0.002) and significantly increased plasma total antioxidant capacity (TAC) levels (+?60.7?±?69.4 vs. ??1.5?±?141.5 mmol/L, P?=?0.03). Results of RT-PCR demonstrated that compared with the placebo, magnesium and zinc co-supplementation downregulated gene expression of interleukin-1 (IL-1) (P?=?0.007) and tumor necrosis factor alpha (TNF-α) (P?=?0.03) in PBMCs of subjects with PCOS. Overall, magnesium and zinc co-supplementation, compared with the placebo, for 12 weeks among PCOS women had beneficial effects on serum hs-CRP, plasma PCO, TAC, and gene expression of IL-1 and TNF-α. Clinical trial registration number: http://www.irct.ir: IRCT201706075623N121. 相似文献
96.
U Szybiak-Strózycka P Strózycki M Sikorski B Golińska C Madrzak A B Legocki 《Acta biochimica Polonica》1987,34(2):79-85
Two yellow lupin leghemoglobins, Lb I and Lb II, were purified to homogeneity using the HPLC technique for final separation. Lb I and Lb II were identified by the N-terminal sequences and their reaction with antibodies against electrophoretically pure leghemoglobin. The third Lb species was detected by the combined method of isoelectrofocusing and PAGE of Lb I. It seems that Lb III represents a posttranslational modification of Lb I. Developmental changes in Lb multiple forms were examined using the Western blotting method. The content of leghemoglobin, first detectable approximately 3 weeks after infection, increased up to 6-7 weeks, and then it remained at the same level until 8-9 weeks after the infection. At the early stages of nodule formation Lb I prevailed over Lb II, while later Lb II became the predominant form. This suggests physiological role of particular forms and precise regulation of the expression of Lb genes. 相似文献
97.
Eighteen Fusarium crookwellense isolates from the continents of Australia, Europe, and North America were compared for their ability to produce mycotoxins on corn at 25 °C after 2 weeks. Extracts from corn fermented with each Fusarium isolate were analyzed by thin-layer chromatography (TLC) and gas chromatography/mass spectroscopy (GS/MS) for mycotoxins. Toxins detected were zearalenone (13 isolates), fusarin C (11 isolates), nivalenol (4 isolates), and diacetoxyscirpenol (2 isolates). Zearalenone and fusarin C were produced by isolates from each continent, while nivalenol was detected in the Fusarium isolates originating from Australia and one isolate from the United States.The mention of firm names or trade products does not imply that they are endorsed or recommended by the U.S. Department of Agriculture over other firms or similar products not mentioned 相似文献
98.
Differentiation potential of menstrual blood‐ versus bone marrow‐stem cells into glial‐like cells 下载免费PDF全文
99.
Ali Niapour Fereshteh Karamali Khadijeh Karbalaie Abbas Kiani Mohammad Mardani Mohammad Hossein Nasr-Esfahani Hossein Baharvand 《Biotechnology letters》2010,32(6):781-786
Schwann cells (SCs) can be used to repair both the peripheral and central nervous systems. Therefore, establishment of a procedure
to obtain activated, highly proliferative SCs, in an appropriate time for clinical applications, is a prerequisite. Purification
is complicated by contamination with fibroblasts which often become the predominant cell type in an in vitro SC culture. This
study describes a novel and efficient method to enrich SCs by utilizing the differential detachment properties of the two
cell types. In culture, cells were treated with two different media and the chelator, EGTA, which detached SCs faster than
fibroblasts and allowed for easy isolation of SCs. Within seven days, high yields of SCs with a purity of greater than 99%
were achieved. This was confirmed by immunostaining characterization and flow-cytometric analyses using an antibody against
the p75 low affinity nerve growth factor receptor (p75LNGFR). The entire procedure was completed in approximately 21 days.
This method has the advantage of being technically easier, faster, and more efficient than other previously described methods.
An SC culture that was about 99% homogenous was achieved. 相似文献
100.
A modification of the iodometric technique using an overlay gel was employed for fast identification and isolation of beta-lactamase types TEM, SHV and AmpC from non-denaturing gels. Osmotic shock preparations of the three beta-lactamases were run on polyacrylamide gels without SDS and ampicillin containing overlay gels were flooded with the iodine solution before being placed on polyacrylamide gel strips. Distinct clear bands appeared in dark blue backgrounds indicating beta-lactamase activity. 相似文献