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Experience in treating 76 patients who were subjected to various sphincter-preserving operations is analysed. It is shown that after subtotal resection of the large intestine with ++abdomino-anal resection of the rectum and pull-through of the right parts of the colon into the anal canal as well as after pull-through of the segment of the transverse colon into the anal canal, the neuro-reflex activity of the musculus sphincter ani internus is destroyed in 55% and reduces in 25% of patients while the reflex activity of the musculus sphincter ani externus is disturbed in 45% of patients and is not restored later. The results bear evidence that the condition of the rectal obturation apparatus does not depend on the segment of the colon subjected to the pull-through operation (cecum, ascending colon, transverse colon). Experience has shown that the results of sphicterometry, electromyography, and electromanometry in various periods after colectomy, mucosectomy of the rectum, and formation of ileorectal anastomosis are much better than those after pull-through operations on various parts of the colon, and return to normal values in 18 months.  相似文献   
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Research Institute of Experimental Diagnosis and Treatment of Tumors, Oncologic Scientific Center, Russian Academy of Medical Sciences, Moscow. Troitsk Branch, I.V. Kurchatov Institute of Atomic Energy, Moscow Region. (Presented by Academician of the Russian Academy of medical Sciences, N. N. Trapeznikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 113, No. 6, pp. 636–638, June, 1992.  相似文献   
5.
An intravascular gas exchange device for the treatment of respiratory failure consisted of a multitude of blind-ended hollow fibers glued in a pine-needle arrangement to a central gas supply catheter. It has previously been shown that gas desorption rates can be significantly enhanced by cycling gas pressure between a hypobaric level of 130 and an ambient level of 775 Torr. In this study, influences of the cycling frequency (f) and the cycle fraction during which hypobaric pressure is applied () were investigated. Rates of O2 desorption from O2-saturated water and CO2 desorption from CO2-saturated water into a manifold containing 198 fibers, 380 m in diameter, were measured over a range of f from 0.2 to 1.0 Hz, from 0.1 to 0.8, and fiber lengths from 4 to 16 cm. Relative to operation at ambient pressure, pressure cycling increased O2 transfer 3–4 times and CO2 transfer 4–6 times when the water flowed over the fiber manifold at 2.3 l/min. Transfer rates were relatively insensitive to f and with 80–90% of maximum enhancement obtained when was as low as 0.2. Transfer rates increased continuously with fiber length, implying that pressure cycling reduced the intra-fiber resistance to gas diffusion. A mathematical diffusion model which utilized only two adjustable parameters, a mass transfer coefficient for O2 and for CO2, simulated the trends exhibited by desorption data. © 1998 Biomedical Engineering Society. PAC98: 8745Hw, 8790+y  相似文献   
6.
It was shown previously that exposure to stressors led to a decrease in the number of mitoses in the cornea as a result of G2–M delay. The index of labeled nuclei and level of pathological mitoses were unchanged. It is now shown that injection of pyrogenal or contact hypothermia for 1 h to 28–30°C did not cause reactive inhibition to develop in adrenalectomized rats, but led to a significant increase in the level of pathological mitoses in the cornea from 4.3–6.3% in intact and adrenalectomized rats to 10.6–12.5% in adrenalectomized rats exposed to stress. Karyotypic analysis of the bone marrow cells under these conditions revealed a significant increase in the number of aneuploid cells (both hypo- and hyperdiploid).Central Research Laboratory, Khabarovsk Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR A. M. Chernukh.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 9, pp. 338–341, September, 1979.  相似文献   
7.
Nonstructural protein 3 (NS3) of human hepatitis C virus (HCV) is a conserved multi-functional protein essential for replication and translation of viral RNA and polyprotein processing. Early T-cell response against NS3 is capable of restricting viremia. We aimed at characterizing the immunogenicity in gene immunization of the conserved regions of NS3 critical for protein folding and activity. C57BL/6 mice were injected with NS3 gene of Russian HCV 1b isolate 274933RU. Immunization did not exert any overt histological changes and had no long-term effects on the immune status of NS3 gene-recipients. The immune response in NS3 gene-recipients was screened by antibody ELISA, T-cell proliferation test and immune assays for specific cytokine production. T-lymphocytes of NS3 gene-recipients proliferated in response to peptides representing conserved regions of protease and ATPase/helicase. Stimulated T-lymphocytes produced IL-2, and in response to protease-derived peptides, also IFN-gamma. Potent and long-lasting antibody response was raised against conserved NS3 regions including "Greek-key" motif of protease, motifs II, V and polynucleotide-binding domains of ATPase/helicase. Thus, gene immunization effectively targeted conserved regions critical for NS3 protease and helicase function. In type and specificity, immune response of NS3 gene-immunized mice mimicked immunity achieved in the acute self-limiting HCV infection of human and primates and in virus-exposed healthy individuals, indicating promiscuity of NS3 as immunogen.  相似文献   
8.
Anhydrotetracycline oxygenase was purified both by affinity chromatography and by hydrophobic interaction chromatography. Molecular weight of anhydrotetracycline oxygenase was determined to be 115,000 by Sephadex G-200 gel filtration. Using preparative isoelectric focusing the isoelectric point of the enzyme was estimated to be 5.3. The enzyme showed a sensitivity to thiol-specific inhibitors. During the hydrophobic interaction purification step, the activity dropped considerably. Reactivation occurred when a heat treated crude extract was added to the reaction mixture.  相似文献   
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n = 665, 51%) had an ISS ranging from 0 to 34 (mean 13) had wounds ranging from G1ST (soft tissue wounds caused by low energy transfer) to G3VF (massive wounds with fractures and injury of vital structures) according to the RCWC, with PSS/IS scores from 2 to 105 (mean 60). Statistically significant correlation was found between ISS and PSS/IS as well as RCWC and PSS/IS. Cytokines (IL-1, TNF alpha ) and amino acids responded to a blast injury in similar manner as to gunshot wounds with a greater ISS or more severe RCWC injury type. The subjective sensations in blasted patients (deafness, thoracic pain, vertigo) and mediators, confirmed in previous experimental investigations as important factors in the pathogenesis of blast injuries (TxA 2 , sulfidopeptide leukotrienes) were relationed only to the PSS/IS.RID=" ID=" <E5>Correspondence to:</E5> I. Cernak, M.D., Ph.D.  相似文献   
10.
We studied the influence of 10 synthetic glycoamine analogs on colony formation in 0.3 and 0.9% agarose by metastatic human breast carcinoma (MDA-MB-435) and melanoma (TXM-13) cells. Nine synthetic analogs significantly inhibited the colony formation in 0.9% agarose of MDA-MB-435 human breast carcinoma cells; five compounds caused a 73–83% reduction of colony formation. Seven synthetic glycoamines caused a significant inhibition of colony formation in 0.9% agarose by TXM-13 melanoma cells with the inhibitory effect ranging from 71 to 87%. The 50% inhibition (I50) doses and relative activity rank of the compounds were similar for both breast carcinoma and melanoma cell lines. The murine B16 melanoma cell aggregation assay was employed to elucidate the potential mechanism(s) of the inhibitory activity of synthetic glycoamines. The relative activity ranks of the compounds based on the independently determined I50 doses for both cell aggregation and clonogenic growth assays were very similar for the four most active synthetic analogs and clearly indicated the importance of hydrophobic amino acid in mediating the bioactivity of synthetic glycoamines. In both experimental systems (clonogenic growth in agarose and cell aggregation assay) the leading compound was N-(1-deoxy-d-fructos-1-y1)-d-leucine (Fru-d-Leu) and the least active analog was N-(1-deoxy-d-fructos-1-yl)-glycine (Fru-Gly). These results show that synthetic glycoamines may act by competing for specific carbohydrate-lectin interactions, particularly those involving -galactoside-specific lectins expressed on metastatic cells.  相似文献   
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