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361.
Dashti  N.  Zhang  F.  Hynes  R.  Smith  D.L. 《Plant and Soil》1997,188(1):33-41
We previously reported that application of plant growth-promoting rhizobacteria (PGPR) increased soybean growth and development and, specifically, increased nodulation and nitrogen fixation over a range of root zone temperatures (RZTs) in controlled environment studies. In order to expand on the previous studies, field experiments were conducted on two adjacent sites, one fumigated with methyl bromide and one nonfumigated, in 1994. Two experiments were conducted at each site, one involving combinations of two soybean cultivars and two PGPR strains, the other involving the same factors, but also in combination with two strains Bradyrhizobium japonicum. Soybean grain yield and protein yield were measured. The results of these experiments indicated that co-inoculation of soybean with B. japonicum and Serratia liquefaciens 2-68 or Serratia proteamaculans 1-102 increased soybean grain yield, protein yield, and total plant protein production, compared to the nontreated controls, in an area with low spring soil temperatures. Interactions existed between PGPR application and soybean cultivar, suggesting that PGPRs applied to cultivars with higher yield potentials were more effective. PGPRs applied to the rhizosphere without addition of B. japonicum also increased only leaf area and seed number at the fumigated site. Overall, inoculation of soybean plants with PGPRs in the presence of B. japonicum increased soybean grain yield, grain protein yield, and total plant protein production under short season conditions.  相似文献   
362.
Studies were carried out to determine the effect of the neem product, suneem oil, at two concentrations 10 and 100 ppm, on the second instar larvae of S. littoralis in the laboratory. Two sets of experiments were carried out, choice and no choice. Results showed that suneem oil has anti-feeding and repellency effects on the test insects and it markedly affects the longevity of larvae and pupae, impairs the normal development of larvae and has an effect on the weight of pupae, depending on the concentration used (100 or 10 ppm).  相似文献   
363.
We previously showed 1 that a peptide, Ac-hE18A-NH(2), in which the arginine-rich heparin-binding domain of apolipoprotein E (apoE) [residues 141;-150] (LRKLRKRLLR), covalently linked to 18A (DWLKAFYDKVAEKLKEAF; a class A amphipathic helix with high lipid affinity), enhanced LDL uptake and clearance. Because VLDL and remnants contain more cholesterol per particle than LDL, enhanced hepatic clearance of VLDL could lead to an effective lowering of plasma cholesterol. Therefore, in the present article we compared the ability of this peptide to mediate/facilitate the uptake and degradation of LDL and VLDL in HepG2 cells. The peptide Ac-hE18A-NH(2), but not Ac-18A-NH(2), enhanced the uptake of LDL by HepG2 cells 5-fold and its degradation 2-fold. The association of the peptides with VLDL resulted in the displacement of native apoE; however, only Ac-hE18A-NH(2) but not Ac-18A-NH(2) caused markedly enhanced uptake (6-fold) and degradation (3-fold) of VLDL. Ac-hE18A-NH(2) also enhanced the uptake (15-fold) and degradation (2-fold) of trypsinized VLDL Sf 100;-400 (containing no immuno-detectable apoE), indicating that the peptide restored the cellular interaction of VLDL in the absence of its essential native ligand (apoE). Pretreatment of HepG2s with heparinase and heparitinase abrogated all peptide-mediated enhanced cellular activity, implicating a role for cell-surface heparan sulfate proteoglycans (HSPG). Intravenous administration of Ac-hE18A-NH(2) into apoE gene knockout mice reduced plasma cholesterol by 88% at 6 h and 30% at 24 h after injection. We conclude that this dual-domain peptide associates with LDL and VLDL and results in rapid hepatic uptake via a HSPG-facilitated pathway.  相似文献   
364.
This study aimed to explore the efficiency of carnosine (Cs) and/or l ‐arginine (Agn) in the downregulation of apoptotic and inflammatory molecule expression and DNA damage caused hepatic injury in response to sodium nitrite (Sd)‐induced hypoxia in rats. Rats were injected with Sd; Agn or/and Cs were administrated prior to Sd intoxication. Sd significantly decreased hemoglobin concentration and Bcl‐2 mRNA expression, while increased expressions of apoptotic markers (Bax and caspase), tumor necrosis factor‐α, nuclear factor kappa B, and C‐reactive protein and the oxidative DNA damage in hepatic tissue. Moreover, administration of Agn or/and Cs exhibited a modulation of the previous parameters. However, concurrent treatment with the forementioned antioxidants modulated these levels. It was concluded that the treatment with the combination of Agn and Cs was the most effective regimen in ameliorating Sd toxicity accompanied by hypoxic stress.  相似文献   
365.
Protease enzyme from Bacillus megaterium was successively purified by ammonium sulfate precipitation, ion exchange chromatography on DEAE-cellulose and gel filtration chromatography on Sephadex G-200. The purification steps of protease resulted in the production of two protease fractions namely protease P1 and P2 with specific activities of 561.27 and 317.23 U mg?1 of protein, respectively. The molecular weights of B. megaterium P1 and P2 were 28 and 25 KDa, respectively. The purified fractions P1 and P2 were rich in aspartic acid and serine. Relatively higher amounts of alanine, leucine, glycine, valine, thereonine valine and glutamic acid were also present. The maximum protease activities for both enzyme fractions were attained at 50 °C, pH 7.5, 1% of gelatine concentration and 0.5 enzyme concentrations. P1 and P2 fractions were more stable over pH 7.0–8.5 and able to prolong their thermal stability up to 80 °C. The effect of different inhibitors on the protease activity of both enzyme fractions was also studied. The enzyme was found to be serine active as it had been affected by lower concentrations of phenylmethylsulfonyl fluoride (PMSF). Complete dehairing of the enzyme-treated skin was achieved in 12 h, at room temperature.  相似文献   
366.
Force transmission across the wrist during a grasping maneuver of the hand was simulated for three children with juvenile idiopathic arthritis (JIA) and for one healthy age-matched child. Joint reaction forces were estimated using a series of springs between articulating bones. This method (i.e., rigid body spring modeling) has proven useful for examining loading profiles for normally aligned wrists. A novel method (i.e., sliding rigid body spring modeling) designed specifically for studying joint reaction forces of the malaligned JIA wrist is presented in this paper. Loading profiles across the wrist for the unimpaired child were similar using both spring modeling methods. However, the traditional fixed-end method failed to converge to a solution for one of the JIA subjects indicating the sliding model may be more suitable for investigating loading profiles of the malaligned wrist. The results of this study suggest that a larger proportion of force is transferred through the ulno-carpal joint of the JIA wrist than for healthy subjects, with a less than normal proportion of force transferred through the radio-carpal joint. In addition, the ulnar directed forces along the shear axis defined in this study were greater for all three JIA children compared to values for the healthy child. These observations are what were hypothesized for an individual with JIA of the wrist.  相似文献   
367.
Bacterial infections cause serious illnesses that are treated with antibiotics. Currently used methods for detecting bacterial antibiotic susceptibility consume 48–72 h, leading to overuse of antibiotics. Thus, many bacterial species have acquired resistance to a broad range of available antibiotics. There is an urgent need to develop efficient methods for rapid determination of bacterial susceptibility to antibiotics. The combination of machine learning and Fourier-transform infrared (FTIR) spectroscopy has generated a promising diagnostic approach in medicine and biology. Our main goal is to examine the potential of FTIR spectroscopy to determine the susceptibility of urinary tract infection-Proteus mirabilis to a specific range of antibiotics, within about 20 min after 24 h culture and identification. We measured the infrared spectra of 489 different P. mirabilis isolates and used random forest to analyze this spectral database. A classification success rate of ~84% was achieved in differentiating between the resistant and sensitive isolates based on their susceptibility to ceftazidime, ceftriaxone, cefuroxime, cefuroxime axetil, cephalexin, ciprofloxacin, gentamicin, and sulfamethoxazole antibiotics in a time span of 24 h instead of 48 h.  相似文献   
368.
The class 1 PDZ domain Tip-1 protein was first identified as a binding partner for the Human T-Cell Leukaemia Virus type 1 (HTLV-1) Tax oncoprotein. It was later shown to interact with: the RhoA signaling effector Rhotekin, the Wnt signaling effector β-catenin and the E6 oncoprotein from high-risk HPV16 but not low-risk HPV6. These observations suggested that Tip-1 may be an important “hub” protein that is involved in pathways with a proven link to carcinogenesis. Based on these findings, it was decided to further characterize the cellular role of Tip-1 by carrying out a yeast two-hybrid screen to identify new binding partners in order to uncover potentially novel functions of this protein. This identified an intracellular fragment of the trans-membrane receptor plexin D1 and a C-terminal fragment of the AT hook DNA binding containing 1 (AHDC1) protein which had a carboxyl terminal PDZ binding domain consensus sequence. Both of these interactions were confirmed by yeast mating assay which was also used to show that mutant constructs of AHDC1 lacking the carboxyl PDZ binding site did not bind Tip-1. Immunofluorescent imaging of these proteins in HPV16 E6 expressing human C33A cervical carcinoma cells suggested they may co-localize.  相似文献   
369.
A slime-producing isolate of Staphylococcus epidermidis attached to FDA Group II hydrogel contact lenses persisted on rabbit eyes for up to 14 days, but except for minor redness of the eye no other effect was observed. Eye flora of eight representative New Zealand White rabbits included four different species of Staphylococcus including S. epidermidis and one species of Micrococcus, none of which produced overtly obvious biofilms. The slime-producing strain of S. epidermidis adhered more effectively to lenses than a non-slime-producing strain, and lenses challenged with the slime-producing strain remained on the rabbit eye for longer time periods than those with a non-slime-producing strain. Bacteria associated with the contact lens may affect the retention of the lens on the rabbit cornea during experimental studies.  相似文献   
370.
Background: Medications to prevent the development of NSAID-induced gastric ulcers have a large range of unpleasant side effects. Recent efforts have been focused on determining safer alternative nontoxic and natural forms of anti-ulcer treatments. Methods:Twenty-four male rats were divided into 4 groups: 1: control group that received no treatment; 2: the ndomethacin-treated group that received 20 mg/kg of indomethacin for 2 days to induce the development of gastric ulcers; 3: quercetin-treated group that in addition to the indomethacin treatment, received 50 mg/kg of quercetin 6 hours after and then daily for 14 days and; 4: the melatonin-treated group which received 20 mg/kg of melatonin 6 hours after each indomethacin treatment and then daily for 14 days. All drugs were administered orally. The following parameters were assessed in each group: mean ulcer index of gastric tissue, gastric acid volume and pH, oxidative stress markers: malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH), inflammatory markers: PGE-2, TNF-α, and IL-10, nitric oxide (NO) levels and the relative gene expression of BAX, BCL-2 and COX-2 by real time PCR.Results:Our findings revealed that the indomethacin-treated group had a significantly increased (p< 0.05) ulcer index, gastric acid volume, and elevated levels of stress, inflammatory, and apoptotic markers compared to controls. In the groups that received quercetin or melatonin, these factors were all significantly decreased (p< 0.05). Between quercetin and melatonin, there was no significant difference in their gastroprotective effect. Conclusion:Both quercetin and melatonin had protective antioxidant, anti-inflammatory and antiapoptotic activity against indomethacin-induced gastric ulcers.Key Words: Gastric ulcer, Indomethacin, Melatonin, Quercetin  相似文献   
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