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1.
25 populations from Turkey and one of Syria belonging to theSabulina section of the genusMinuartia have been karyologically examined. New chromosome numbers have been recorded forM. mesogitana andM. hybrida subsp.turcica, and a new variety was found in theM. hybrida complex. The origin of the taxa with n = 23 and n = 35 is discussed.
  相似文献   
2.
The aim of this study was to evaluate the possible protective effects of caffeic acid phenethyl ester (CAPE) against cholestatic oxidative stress and liver damage in the common bile duct ligated rats. A total of 18 male Sprague–Dawley rats were divided into three groups: control, bile duct ligation (BDL) and BDL + received CAPE; each group contain 6 animals. The rats in CAPE treated groups were given CAPE (10 μmol/kg) once a day intraperitoneally (i.p) for 2 weeks starting just after BDL operation. The changes demonstrating the bile duct proliferation and fibrosis in expanded portal tracts include the extension of proliferated bile ducts into lobules, inflammatory cell infiltration into the widened portal areas were observed in BDL group. Treatment of BDL with CAPE attenuated alterations in liver histology. The proliferating cell nuclear antigen and the activity of TUNEL in the BDL were observed to be reduced with the QE treatment. The application of BDL clearly increased the tissue hydroxyproline (HP) content, malondialdehyde (MDA) levels and decreased the antioxidant enzyme (superoxide dismutase (SOD), glutathione peroxidase (GPx)) activities. CAPE treatment significantly decreased the elevated tissue HP content, and MDA levels and raised the reduced of SOD, and GPx enzymes in the tissues. The data indicate that CAPE attenuates BDL-induced cholestatic liver injury, bile duct proliferation, and fibrosis. The hepatoprotective effect of CAPE is associated with antioxidative potential.  相似文献   
3.
Summary Adsorption isotherms for the adsorption of chromium onZoogloea ramigera are developed. The rates were affected by the pH and temperature of adsorption medium. The biomass ofZ. ramigera at pH 2.0 where the optimum pH for biosorption lies exhibited the highest chromium adsorptive uptake capacity. In general, higher adsorptive uptake was observed at 25°C than 35°C and 45°C.  相似文献   
4.
The electron-spin resonance (ESR) was applied to examine human plasma and red cell lipids. In the lipids, the signal of ESR of alpha-tocopherylquinone was recorded. The concentration of the latter in the lipids was found to be elevated in coronary heart disease. Intramuscular injection of 30% oily solution of alpha-tocopherylquinone in a dose of 2 ml two times a day over three days entailed an increase in the concentration of alpha-tocopherylquinone in plasma and red cell lipids.  相似文献   
5.
Based on several samples of Middle and Late Triassic age, the authors describe a new family of spumellarian Radiolaria – Trimeridianellidae Dumitrica and Tekin, characterized by a three-fold symmetry, a first shell of triangular prism type with 6 primary rays originated at the edges of two bases of the prism, or 3 meridian arches with 3 equatorial rays, and growth of pyloniacean type. The family comprises 4 monospecific new genera (Enneacladus Dumitrica, Endoprisma Dumitrica, Trimeridianella Dumitrica and Tekin, and Tristylopyle Dumitrica), 4 new species and one left in open nomenclature. In spite of their spotty occurrences and low diversity, the authors attempt to trace the evolution of the family, which is considered to be the result of heterochrony in ontogenetic growth, mostly of paedomorphic type. The family seems to be related to the Middle Triassic family Patruliidae Dumitrica with which it shares in common the simple microsphere with 6 primary rays and the pyloniacean mode of growth.  相似文献   
6.
Use of small interfering RNA (siRNA) is a promising approach for AML treatment as the siRNA molecule can be designed to specifically target proteins that contribute to aberrant cell proliferation in this disease. However, a clinical-relevant means of delivering siRNA molecules must be developed, as the cellular delivery of siRNA is problematic. Here, we report amphiphilic carriers combining a cationic polymer (2 kDa polyethyleneimine, PEI2) with lipophilic moieties to facilitate intracellular delivery of siRNA to AML cell lines. Complete binding of siRNA by the designed carriers was achieved at a polymer:siRNA ratio of ~0.5 and led to siRNA/polymer complexes of ~100 nm size. While the native PEI2 did not display cytotoxicity on AML cell lines THP-1, KG-1 and HL-60, lipid-modification on PEI2 slightly increased the cytotoxicity, which was consistent with increased interaction of polymers with cell membranes. Cellular delivery of siRNA was dependent on the nature of lipid substituent and the extent of lipid substitution, and varied among the three AML cell lines used. Linoleic acid-substituted polymers performed best among the prepared polymers and gave a siRNA delivery equivalent to better performing commercial reagents. Using THP-1 cells and a reporter (GFP) and an endogenous (CXCR4) target, effective silencing of the chosen targets was achieved with 25 to 50 nM of siRNA concentrations, and without adversely affecting subsequent cell growth. We conclude that lipid-substituted PEI2 can serve as an effective delivery of siRNA to leukemic cells and could be employed in molecular therapy of leukemia.  相似文献   
7.
    
Process development for biologics is expensive and lengthy, tools are needed to rapidly understand where the difficulties will lie, and, hence, rationally deploy resources. In this work we introduce and evaluate a methodology to determine the manufacturability of a protein candidate. The methodology determines protein impurities by mass spectrometry and separation difficulty from the product based on adsorption properties deduced from a single set of experiments. This information can aid early process strategy decisions to target hard to remove protein impurities (nearest neighbors) and allow the re-evaluation of conventional process synthesis. The methodology chosen gives consideration to the fact that at this point in early phase development, material, and established analytical methods are limiting. This study uses surface enhanced laser desorption ionization mass spectroscopy (SELDI-MS), for its rapid analysis and minimal sample requirement to measure product and contaminant adsorption properties. The technique is used to provide an array of hydrophobic and electrostatic conditions for protein adsorption. The adsorption pattern produced for each protein is analyzed and visualized via a star plot. Dendrograms then define nearest neighbor protein contaminants by quantifying differences in the adsorption pattern between the product and contaminants. By comparison to an existing process to manufacture a 28 kDa recombinant protein expressed in Escherichia coli, we confirm the method is capable of determining where the greatest separation difficulty lies and what separation methods should be considered. The technique identified that the nearest neighbor contaminants were product-related proteins (28.6 and 29.1 kDa/e). Thus demonstrating a capability to measure the relative difficulty of purifying early stage protein candidates where little is known about the separation properties of products and contaminants, or the process sequence for their production.  相似文献   
8.
    
Altered expression of multiple miRNAs was found to be extensively involved in the pathogenesis of different neurological disorders including Alzheimer's disease, Parkinson's disease, stroke, epilepsy, multiple sclerosis, amyotrophic lateral sclerosis, and Huntington's disease. One of the biggest concerns within gene-based therapy is the delivery of the therapeutic microRNAs to the intended place, which is obligated to surpass the biological barriers without undergoing degradation in the bloodstream or renal excretion. Hence, the delivery of modified and unmodified miRNA molecules using excellent vehicles is required. In this light, mesenchymal stem cells (MSCs) have attracted increasing attention. The MSCs can be genetically modified to express or overexpress a particular microRNA aimed with promote neurogenesis and neuroprotection. The current review has focused on the therapeutic capabilities of microRNAs-overexpressing MSCs to ameliorate functional deficits in neurological conditions.  相似文献   
9.
Alginate matrix tablet of diltiazem hydrochloride (DTZ), a water-soluble drug, was prepared using sodium alginate (SAL) and calcium gluconate (CG) by the conventional wet granulation method for sustained release of the drug. The effect of formulation variables like SAL/CG ratio, drug load, microenvironmental pH modulator, and processing variable like compression force on the extent of drug release was examined. The tablets prepared with 1:2 w/w ratio of SAL/CG produced the most sustained release of the drug extending up to 13.5 h. Above and below this ratio, the drug release was faster. The drug load and the hardness of the tablets produced minimal variation in drug release. The addition of alkaline or acidic microenvironmental modulators did not extend the release; instead, these excipients produced somewhat faster release of diltiazem. This study revealed that proper selection of SAL/CG ratio is important to produce alginate matrix tablet by wet granulation method for sustained release of DTZ.  相似文献   
10.
  总被引:2,自引:0,他引:2  
In the course of a systematic survey of DMD and BMD patients with intronic probes and with cDNA probes covering three-fourths of the coding sequence, 45 molecular deletions within the DMD gene were investigated. Forty-two percent of the breakpoints were located in the intronic sequence containing probe P20, whereas the other deletions were widespread around the more proximal part of the gene. Most of the BMD deletions were in the P20 region. Pulsed field gel electrophoresis was used to determine the size of some deletions and allowed us to estimate the physical distance between the intronic probes JBir and P20. The reading frame was checked in 11 cases with proximal deletions and found to be disrupted in 6 of 7 DMD patients, in 1 intermediate case, and, unexpectedly, in 3 BMD patients.  相似文献   
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