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21.
Complex protein preparations obtained from pneumococci have been used for the serological examination of patients with pneumococcal infection. The proposed system of ELISA permits the detection of positive results in about 70% of cases. The specificity of the method is 95%. Special attention is paid to the determination of the criterion indicating the presence of positive results.  相似文献   
22.
Topographic interrelations of the arcuate nucleus (AN) neurons expressing the dopamine-synthesized enzymes, tyrosine hydroxylase (TH) and/or aromatic L-amino acid decarboxylase (AAD), as well as projections of axons of these neurons to the medial eminence were studied in male rats at the 21st embryonal and 9th postnatal days as well as in adult animals. The method of double immunocytochemical labeling and its modification were used to reveal these enzymes. For identification of immunoreactive neurons, a confocal microscope was used. At all ontogenetic stages, three populations of neurons were found, which differed by composition of the dopamine-synthesizing enzymes as well as by the character of topographic interrelations of the TH-expressing monoenzyme neurons with the AAD-expressing neurons. In ontogeny, the topographic tight junctions are formed between the monoenzyme TH- and AAD expressing neurons at the level of both the cell body and the distal axons, which seems to increase effectiveness of the L-dihydroxyphenylalanine (L-DOPA) transfer from the TH- to the AAD-expressing neurons. The TH- and AAD expressing monoenzyme neurons project their axons to the medial prominence to provide entrance of the products of the specific syntheses into the pituitary portal circulating system. Thus, the morphological data obtained confirm indirectly our hypothesis about a cooperative participation of the TH- and AAD-expressing monoenzyme neurons of the AN in the dopamine synthesis.  相似文献   
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Forty-eight patients of resuscitation wards were examined, including 15 patients with purulent peritonitis, 12 patients with acute pancreatitis, 11 patients with thermal skin damages, and 10 patients with severe acetic acid intoxication. An increase in the serum iron, ferritin, and free hemoglobin contents of blood plasma influenced the severity of endotoxicosis. This was expressed in progressive fever, increase in the leukocytic intoxication index and concentrations of low-and middle-molecular-weight substances on erythrocytes and in the blood plasma, intensification of lipid peroxidation, and insufficiency of the antioxidant defense system, which resulted in the development of multiple organ failure in patients with the above-mentioned diseases.  相似文献   
26.
The results of the clinical trials of human recombinant interferon alpha-2 (reaferon) make it possible to come to the conclusion that the preparation is well-tolerated and produces a pronounced therapeutic effect in a number of viral and oncological diseases. The Pharmacological Committee of the USSR has recommended reaferon for use in acute hepatitis B, hairy cell leukemia, renal cancer at stage IV, disseminated sclerosis, ocular herpes. The use of reaferon has been found to be promising in the treatment of papillomatosis of the larynx, Kaposi's sarcoma, mycosis fungoides, chronic myeloleukemia.  相似文献   
27.
Modern proteomic techniques make it possible to identify numerous changes in protein expression in tumors as compared to normal tissues. Although proteomics is currently widely used, identification of proteins differentially expressed in particular types of cancer remains a challenging task. The goal of our study was to detect novel protein markers of colorectal cancer using comparative proteomics of protein extracts obtained from primary tumors and adjacent normal tissues. Coloreetal cancer is nearly asymptomatic at the early stages, which calls for development of fast and sensitive methods for molecular diagnostics. Proteomes of 11 paired specimens of primary colorectal tumors and adjacent histologically normal tissues were studied using comparative 2D PAGE. Altogether, 16 proteins with altered expression levels were detected, including 13 proteins with increased levels and three proteins with decreased levels in tumor tissues. These proteins were identified using MALDI-TOF mass spectrometry. The proteins GPD1, RRBP1 (increased levels), HNRNPH1, and SERPINB6 (decreased levels) have been associated with colorectal cancer for the first time.  相似文献   
28.
The regulatory decrease in the volume of principal cells of collecting ducts to hypoosmotic shock has been investigated experimentally and using the mathematical modeling. A mathematical model of the response of collecting duct principal cells to hypotonic shock has been constructed on the basis of the experimental time course of changes in cell volume measured by the fluorescent dye Calcein. It was shown that the regulatory decrease in volume under hypotonic conditions occurs via a marked release of osmolytes and is accompanied by a decrease in water permeability of the cell membrane. The mathematical modeling of transmembrane transport processes allowed us to quantitatively estimate the changes in membrane water permeability, which decreased tenfold, from 2 x 10(-1) cm/s to 2 x 10(-2) cm/s. It was also shown that the effective regulatory decrease in the volume of collecting duct principal cells in hypotonic medium results from a significant increase in membrane permeability for K+, Cl-, and organic anions.  相似文献   
29.
Ilyaskin  A. V.  Baturina  G. S.  Medvedev  D. A.  Ershov  A. P.  Solenov  E. I. 《Biophysics》2011,56(3):516-524
The reaction of rat kidney collecting duct principal cells to hypotonic shock was studied. The changes in cell relative volume were measured using fluorescent dye calcein, and a mathematical model based on our experimental results was developed. It was shown that regulatory volume decrease is mainly provided by significant release of osmolytes from the cell and decrease of the plasma membrane water permeability. Using our model, we calculated the membrane water permeability and found it to decrease from 2 · 10−1 to 2 · 10−2 cm/s. We conclude that for effective RVD to occur, a dramatic increase in the membrane permeability to K+, Cl and organic anions is necessary.  相似文献   
30.
In medical and pharmaceutical applications, chitosan is used as a component of hydrogels–macromolecular networks swollen in water. Chemical hydrogels are formed by covalent links between the crosslinking reagents and amino functionalities of chitosan. To date, the most commonly used chitosan crosslinkers are dialdehydes, such as glutaraldehyde (GA). We have developed novel GA like crosslinkers with additional functional groups–dialdehyde derivatives of uridine (oUrd) and nucleotides (oUMP and oAMP)–leading to chitosan-based biomaterials with new properties. The process of chitosan crosslinking was investigated in details and compared to crosslinking with GA. The rates of crosslinking with oUMP, oAMP, and GA were essentially the same, though much higher than in the case of oUrd. The remarkable difference in the crosslinking properties of nucleoside and nucleotide dialdehydes can be clearly attributed to the presence of the phosphate group in nucleotides that participates in the gelation process through ionic interactions with the amino groups of chitosan. Using NMR spectroscopy, we have not observed the formation of aldimine bonds. It can be concluded that the real number of crosslinks needed to cause gelation of chitosan chains may be less than 1%.  相似文献   
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