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A histological stain prepared from the heartwood of Pterocarpus santalinus Linn. has been found to be an excellent nuclear stain for various cells of animal and plant origin. As an elastic tissue stain, the results are comparable to standard elastic tissue stains. The striations of voluntary muscle fibers are well shown. The Nissl granules and fibers of cranial nerves in the pons are visualized. When counterstained with light green, it differentially stains muscle and fibrous tissue. The stain can be used as counterstain with certain histochemical procedures with satisfactory results. The preparation and use of this versatile stain are described.  相似文献   
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The efficiency of a new anticestode compound, 3,5-dibromo-2'-chloro-4'-isothiocyanato salicylanilide (GUPTA et al. 1980) for mass eradication of hymenolepiasis from rat colonies was assessed in a pilot study. The drug was administered with milk or food. For effective eradication, depending on the size of animals, single or multiple doses of 100 to 500 mg of the drug/kg body-weight, mixed in milk, or 50 mg/kg in feed were necessary. Better results were obtained when the compound was given in feed as it ensured effective consumption irrespective of the seasonal variations. The efficacy of the compound was also assessed on cysticercoids in intermediate hosts (Tribolium confusum) by feeding them on flour medicated at 5%, 1% and 0.1% levels. None of the concentrations killed the larvae or arrested their development.  相似文献   
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Carbon-13 NMR spectra of the reconcentrated chromaffin granule lysate have been obtained at 50 MHz and 62.9 MHz. The spectrum contains a number of assignable resonances in addition to those of the main soluble components (catecholamines, adenine nucleotides and chromogranin). Guanine and uridine nucleotides are present at levels of 0.13 and 0.08 mol/mol adenine nucleotides, respectively. Concentrations of cytidine nucleotides and NAD+ are below the detection limit (0.02 mol/mol adenine nucleotides). An unidentified low molecular weight species, thought to be an adenine-containing oligonucleotide, is also present. Ascorbic acid was observed at a concentration of 0.14 mol/mol adenine nucleotides, but both dopamine and dehydroascorbic acid were below the detection limit. Protein resonances agree well with the reported amino acid composition of chromogranin A, with the exception of tryptophan and glutamine which have not previously been measured. The concentrations of these residues are estimated to be 12 ± 3 and 39 ± 5 residues per 77 000 dalton unit of chromogranin A. Substantial intensity due to unsaturated fatty acid side-chains in solubilized lipid is seen in the olefinic carbon region and in the methylene region, suggesting the presence of lipoprotein. Unassigned carbohydrate resonances are also present, but are largely obscured by sucrose in the isolation medium.  相似文献   
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Baculoviruses have enormous potential for use as biopesticides to control insect pest populations without the adverse environmental effects posed by the widespread use of chemical pesticides. However, continuous baculovirus production is susceptible to DNA mutation and the subsequent production of defective interfering particles (DIPs). The amount of DIPs produced and their genome length distribution are of great interest not only for baculoviruses but for many other DNA and RNA viruses. In this study, we elucidate this aspect of virus replication using baculovirus as an example system and both experimental and modeling studies. The existing mathematical models for the virus replication process consider DIPs as a lumped quantity and do not consider the genome length distribution of the DIPs. In this study, a detailed population balance model for the cell‐virus culture is presented, which predicts the genome length distribution of the DIP population along with their relative proportion. The model is simulated using the kinetic Monte Carlo algorithm, and the results agree well with the experimental results. Using this model, a practical strategy to maintain the DIP fraction to near to its maximum and minimum limits has been demonstrated.  相似文献   
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Dickkopf-1 (DKK1) is an inhibitor of the Wnt/β-catenin signaling pathway. However, the role of DKK1 in the progression of non small cell lung cancer (NSCLC) is not fully understood. In this study, RT-PCR and Western blot were used to examine the expression of DKK1 in a panel of ten human NSCLC cell lines and NSCLC tissues. DKK1 expression was highly transactivated in the great majority of these cancer lines. The expression of DKK1 was upregulated on both mRNA and protein levels in NSCLC tissues compared with the adjacent normal lung tissues. Immunohistochemistry and immunofluoresence revealed that DKK1 was mainly distributed in the cytoplasm in both carcinoma tissues and cell lines. DKK1 protein expression was also evaluated in paraffin sections from 102 patients with NSCLC by immunohistochemistry, and 65(63.73%)tumors were DKK1 positive. Relative analysis showed a significant relationship between DKK1 positive expression and lymph node metastasis(P<0.05). Patients with DKK1-positive tumors had poorer DFS than those with negative ESCC (5-year DFS; 15.4% versus 27%, P = 0.007). To further explore the biological effects of DKK1 in NSCLC cells, we over-expressed DKK1 in NSCLC 95C cell using eukaryotic expression vector pCMV-Tab-2b and performed a knockdown of DKK1 in LTEP-a-2 cell using a short hairpin RNA expression vector pSilencer 5.1. DKK1 did not have any effect on proliferation, but seemed to play a role in migration and invasion capability. Overexpression of DKK1 promotes migratory and invasive activity of 95C, while DKK1 knockdown resulted in the suppression of migration and invasion potentials of LTEP-a-2 cell. Taken together, these results indicate that DKK1 may be a crucial regulator in the progression of NSCLC. DKK1 might be a potential therapeutic target in NSCLC.  相似文献   
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