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471.
Highly sensitive diagnostic preparations for the detection of C. trachomatis by direct immunofluorescent and enzyme immunoassay techniques were obtained with the use monoclonal antibodies to C. trachomatis genus-specific polysaccharide antigen. The enzyme immunoassay diagnostic preparation permitted the detection of C. trachomatis in experimental specimens in a dose of 4-14 ng protein. The results of the primary clinical trial of the immunofluorescent preparation revealed that its effectiveness was not lower than that of similar foreign commercial preparations. The use of this diagnosticum for the study of clinical material obtained from 1,603 patients with different venereal diseases showed the presence of chlamydial contamination in 40.2% of the examined patients. The data thus obtained made it possible to recommend the newly developed immunofluorescent preparation for diagnosing infections caused by C. trachomatis. 相似文献
472.
EI Blount 《Canadian Metallurgical Quarterly》1988,37(10):5884-5885
473.
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M Derrick KK Gan P Kooijman JS Loos B Musgrave LE Price J Schlereth K Sugano JM Weiss DE Wood D Blockus B Brabson SW Gray C Jung H Neal H Ogren DR Rust M Valdata-Nappi C Akerlof G Bonvicini J Chapman D Errede N Harnew P Kesten DI Meyer D Nitz AA Seidl R Thun T Trinko M Willutzky S Abachi P Baringer I Beltrami BG Bylsma R DeBonte D Koltick FJ Loeffler EH Low U Mallik RL McIlwain DH Miller CR Ng LK Rangan EI Shibata B Cork 《Canadian Metallurgical Quarterly》1986,34(11):3286-3303
476.
K Tenhunen A Uusitalo T Autti R Joensuu M Kettunen RA Kauppinen S Ikonen ME LaMarca M Haltia EI Ginns A Jalanko L Peltonen 《Canadian Metallurgical Quarterly》1998,57(12):1154-1163
Aspartylglucosaminuria (AGU) is a recessively inherited lysosomal storage disorder caused by the deficiency of the aspartylglucosaminidase (AGA) enzyme. The hallmark of AGU is slowly progressing mental retardation but the progression of brain pathology has remained uncharacterized in humans. Here we describe the long-term follow-up of mice carrying a targeted AGU-mutation in both alleles. Immunohistochemistry, histology, electron microscopy, quantitative magnetic resonance imaging (MRI) and behavioral studies were carried out to evaluate the CNS affection of the disease during development. The lysosomal storage vacuoles of the AGA -/- mice were most evident in central brain regions where MRI also revealed signs of brain atrophy similar to that seen in the older human patients. By immunohistochemistry and MRI examinations, a subtle delay of myelination was observed in AGA -/- mice. The life span of the AGA -/- mice was not shortened. Similar to the slow clinical course observed in human patients, the AGA -/- mice have behavioral symptoms that emerge at older age. Thus, the AGU knock-out mice represent an accurate model for AGU, both histopathologically and phenotypically. 相似文献
477.
Dietary intake, physical development and some indicator of health status of schoolchildren of Novosybkov (2th zone of strict control) and Vyshkov (3th zone) were studied. Energy and macronutrient intakes for schoolchildren can be considered adequate. Dietary intake intake of vitamins A, E, beta-carotene and especially C, and calcium were rather low. Low intakes of vitamin and calcium are results from low dietary consumption of milk and diary products, fruits and vegetables Physical development of Novosybkov's children is considered adequate and do not differ from that of Moscow's schoolchildren. The frequency of obese schoolchildren was seen in Novosybkov's children in comparison with Moscow's ones. On the contrary, among rural Vyshkov's children the high frequency of children with deficit of body mass was examined. The number of children relating to 2 or 3 groups of health was higher in Novosybkov than in Moscow. The data about higher prevalence of child morbidity were supported. One of risk factors of decreasing of children body toleration to low level of radiation are low level of vitamin intake and other defects of health nutrition. 相似文献
478.
Previous studies have shown that Borrelia burgdorferi, the spirochetal agent of Lyme disease, promotes inflammation by stimulating endothelial cells to upregulate adhesion molecules for leukocytes and to produce a soluble agent that is chemotactic for neutrophils. We determined that interleukin-8 (IL-8) was the chemotactic agent for neutrophils present in conditioned media from cultured human umbilical vein endothelial cells stimulated with B. burgdorferi. As few as one spirochete per endothelial cell stimulated production of IL-8 within 8 h of coincubation. When 10 spirochetes per endothelial cell were added, IL-8 was detected after 4 h of coculture. Production of IL-8 continued in a linear fashion for at least 24 h. Neutralizing antibodies against IL-8 reduced migration of neutrophils across spirochete-stimulated endothelial monolayers by 93%. In contrast, pretreatment of neutrophils with antagonists of platelet-activating factor did not inhibit migration. Increases in production of IL-8 and expression of the adhesion molecule E-selectin by endothelial cells in response to B. burgdorferi were not inhibited by IL-1 receptor antagonist or a neutralizing monoclonal antibody directed against tumor necrosis factor alpha, used either alone or in combination. These results suggest that activation of endothelium by B. burgdorferi is not mediated through the autocrine action of secreted IL-1 or tumor necrosis factor alpha. Rather, it appears that B. burgdorferi must stimulate endothelium either by a direct signaling mechanism or by induction of a novel host-derived proinflammatory cytokine. 相似文献
479.
ES Belyaeva IF Zhimulev EI Volkova AA Alekseyenko YM Moshkin DE Koryakov 《Canadian Metallurgical Quarterly》1998,95(13):7532-7537
A genetic locus suppressing DNA underreplication in intercalary heterochromatin (IH) and pericentric heterochromatin (PH) of the polytene chromosomes of Drosophila melanogaster salivary glands, has been described. Found in the In(1)scV2 strain, the mutation, designated as Su(UR)ES, was located on chromosome 3L at position 34. 8 and cytologically mapped to region 68A3-B4. A cytological phenotype was observed in the salivary gland chromosomes of larvae homozygous and hemizygous for Su(UR)ES: (i) in the IH regions, that normally are incompletely polytenized and so they often break to form "weak points," underreplication is suppressed, breaks and ectopic contacts disappear; (ii) the degree of polytenization in PH grows higher. That is why the regions in chromosome arm basements, normally beta-heterochromatic, acquire a distinct banding pattern, i. e., become euchromatic by morphological criteria; (iii) an additional bulk of polytenized material arises between the arms of chromosome 3 to form a fragment with a typical banding pattern. Chromosome 2 PH reveals additional alpha-heterochromatin. Su(UR)ES does not affect the viability, fertility, or morphological characters of the imago, and has semidominant expression in the heterozygote and distinct maternal effect. The results obtained provide evidence that the processes leading to DNA underreplication in IH and PH are affected by the same genetic mechanism. 相似文献
480.
EI Levy B Clyde MR McLaughlin PJ Jannetta 《Canadian Metallurgical Quarterly》1998,43(1):1-6; discussion 6-9
OBJECTIVE: To demonstrate that microvascular decompression of the left medulla oblongata is a safe and effective modality for treating elevated blood pressure in patients with severe medically refractory "essential" hypertension (HTN). METHODS: Twelve patients with medically intractable HTN with or without autonomic dysreflexia underwent microvascular decompression of the left rostral ventrolateral medulla oblongata. Causes such as pheochromocytoma, carcinoid syndrome, and renal disease were ruled out before surgery. Indications for surgery included systolic blood pressures greater than 180 mm Hg refractory to three or more medications, severe blood pressure lability, or medically resistant HTN at systolic pressures greater than 160 mm Hg associated with autonomic dysreflexia and/or magnetic resonance images demonstrating left medullary compression. The median age and follow-up duration were 51 years and 4.1 years, respectively. RESULTS: Ten of 12 patients experienced reductions in systolic blood pressure greater than 20 mm Hg. Of these 10 patients, pressure reductions were temporary (6 mo) in two. Seven of eight patients experienced improvement in blood pressure lability and/or autonomic dysreflexia, with five patients showing sustained improvements. CONCLUSION: Microvascular decompression of the left rostral ventrolateral medulla oblongata may be an effective treatment modality for patients suffering from severe HTN and/or autonomic dysreflexia refractory to medical management. 相似文献