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The presence of heat stress protein genes (hsp) was tested by Southern hybridization analysis in total DNA extracts from species of the genus Streptococcus (47 strains), Lactobacillus (34 strains), Lactococcus (24 strains), and Leuconostoc (5 strains). The biotinylated hsp16.4 probe prepared from an ORF2 fragment of pER341 (2.8 kb) tested positively with restricted DNA extracts of seven Streptococcus thermophilus strains and a single strain of Lactococcus lactis subsp. cremoris. In all positive S. thermophilus strains, the hsp was located on plasmids ranging from ca. 2.8 kb to 11 kb in size, while hsp was present in a 7.5-kb plasmid in Lactococcus lactis subsp. cremoris. Southern blots with a rep probe showed that all hsp16.4+ plasmids in S. thermophilus strains also shared homology with the replication function (rep) of pER341, suggesting the common origin of these plasmids.  相似文献   

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No quantitative, simple and non-radioactive method has been described for measuring the platelet content of experimental thrombi. The aim of the present study was to develop a simple method for quantifying platelets in thrombi formed on thrombogenic surfaces in flowing native human blood. To test the relevance of this new method, the effect of unfractionated heparin on arterial thrombus formation was investigated. Tissue factor (TF)- and collagen-coated coverslips were exposed to non-anticoagulated blood at an arterial wall shear rate (2,600 s(-1)) for 1 to 4 min. Platelet deposition was quantified by measuring the P-selectin (PS) and beta-thromboglobulin (betaTG) content of dissolved plasmin-digested thrombi using immunoenzymoassays; fibrin deposition was determined by measuring the D-dimer levels. These results were compared to those established by morphometrical analysis. Morphometric evaluation showed that fibrin deposition was maximum on TF by 1 min perfusion time. Platelets deposited subsequently and reached a maximum at 3 min. On collagen, platelets deposited directly on the collagen fibrils without detectable fibrin deposit. Platelet deposition increased from 1 to 4 min. Platelet deposition quantified by PS was correlated to the values obtained by morphometry (r = 0.72, r = 0.67, p <0.001, on TF and collagen, respectively). As compared to PS, betaTG measurements gave an underestimation of the size of the thrombus platelet number. Unfractionated heparin infused through a mixing device proximal to the perfusion chamber to obtain plasma concentrations of 0.5, 1 and 3 IU/ml, reduced fibrin deposition on TF-coated coverslips in a dose-dependent manner (77% reduction at 3 IU/ml, p <0.01), but had no significant effect on platelet deposition (33% at 3 IU/ml, p >0.05). In contrast, heparin had no effect on fibrin or platelet deposition on collagen-coated coverslips. Thus, a new quantitative and simple method for measuring platelet deposition in flowing blood has been developed and characterized. Utilizing this system, we have demonstrated that unfractionated heparin did not inhibit arterial thrombus formation either on procoagulant or on proaggregant surface.  相似文献   

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IS INFORMATION A TOOL FOR PREVENTIVE ACTION? The aim of this study was to evaluate maternal beliefs concerning neonatal performances, to compare them with currently accepted knowledge and to analyse parameters that could influence the maternal judgement. POPULATION AND METHODS: A total of 189 mothers in the postpartum period were prospectively questioned about their beliefs concerning the developmental visual, auditive, olfactive, gustative and sensitive functions of their neonates. RESULTS: Only 57.7% of mothers agreed with the fact that their neonates were able to see. Similarly, there were more than 80% for the olfactive and gustative function and more than 90% for the auditive function and pain discrimination. Multiparity and high level of professional activities improved the mothers' answers about the visual abilities of their neonates. Scientific information through media appeared poorly assimilated. CONCLUSIONS: The time spent by the mothers in the maternity home or word could be used to inform them.  相似文献   

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2006年10月1日起实施的《清洁生产标准钢铁行业》(HJ/T189-2006)存在着一些不足之处,如不及时修订,将无法适应“十一五”期间钢铁工业的发展形势和清洁生产形势,在某种程度上还很容易对国内钢铁企业造成误导,而且会产生一些负面不良影响。根据目前我国钢铁工业的发展形势和国内外钢铁企业已经达到的实际清洁生产水平,就其存在的问题和今后的修订谈了一些看法。  相似文献   

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Structural and biochemical studies suggest that serpins induce structural rearrangements in their target serine-proteinases. Previous NMR studies of the complex between a serpin, alpha1-proteinase inhibitor, and a mutant of recombinant rat trypsin (the Asp189 to Ser mutant, D189S, which is much more stable than wild-type rat trypsin against autoproteolysis) provided information about the state of catalytic residues in this complex: the hydrogen bond between Asp102 and His57 remains intact in the complex, and spectral properties of His57 are more like those of the zymogen than of the activated enzyme (G. Kaslik, et al., 1997, Biochemistry 36, 5455-5464). Here we report the protonation and exchange behavior of His57 of recombinant rat trypsin D189S in three states: the zymogen, the active enzyme, and the complex with human alpha1-proteinase inhibitor and compare these with analogous behavior of His57 of bovine chymotrypsinogen and alpha-chymotrypsin. In these studies the pKa of His57 has been determined from the pH dependence of the 1H NMR signal from the Hdelta1 proton of histidine in the Asp102-His57 dyad, and a measure of the accessibility of this part of the active site has been obtained from the rate of appearance of this signal following its selective saturation. The activation of rat trypsinogen D189S (zymogen, pKa = 7.8 +/- 0.1; Hill coefficient = 0. 86 +/- 0.05) decreased the pKa of His57 by 1.1 unit and made the protonation process cooperative (active enzyme, pKa = 6.7 +/- 0.1; Hill coefficient = 1.37 +/- 0.08). The binding of alpha1-proteinase inhibitor to trypsin D189S led to an increase in the pKa value of His57 to a value higher than that of the zymogen and led to negative cooperativity in the protonation process (complex, pKa = 8.1 +/- 0. 1; Hill coefficient = 0.70 +/- 0.08), as was observed for the zymogen. In spite of these differences in the pKa of His57 in the zymogen, active enzyme, and alpha1-proteinase inhibitor complex, the solvent exchange lifetime of the His57 Hdelta1 proton was the same, within experimental error, in all three states (lifetime = 2 to 12.5 ms). The linewidth of the 1H NMR signal from the Hdelta1 proton of His57 was relatively sharp, at temperatures between 5 and 20 degrees C at both low pH (5.2) and high pH (10.0), in spectra of bovine alpha-chymotrypsin, recombinant rat trypsin D189S, and the complex between rat trypsin D189S and human alpha1-proteinase inhibitor; however, in spectra of the complex between alpha-chymotrypsin and human alpha1-proteinase inhibitor, the peak was broader and could be well-resolved only at the lower temperature (5 degrees C).  相似文献   

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This paper will explore the delivery of mental health nursing care within a neo-liberal model of mental health care delivery in New Zealand. Mental health nursing as a socially constructed activity occurs within a particular political context, which determines its role and function. This environment determines the nature of the nurse-patient relationship which is integral to the role of mental health nurses. Critical analysis of the New Zealand Government's neo-liberal health policies will be conducted to explore their effect on mental health care delivery and the nurse-patient relationship. Some of the ideologies and values maintained by current dominant discourses within nursing and the State are discussed. To establish therapeutic partnerships with service-users, mental health nurses are urged to critically analyse their practice and the context in which it occurs.  相似文献   

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Three new analogues of trypsin inhibitor CMTI-III were synthesized by the solid-phase method: [Lys5]-CMTI-III, [Orn5]CMTI-III and [Dab5]CMTI-III. Only one analogue with L-lysine residue in position P1 showed inhibitory activity of the same order of magnitude as did wild CMTI-III. Two remaining analogues were completely inactive. A conclusion was drawn that the distance between the basic group of the amino acid residue's side chain in position P1 of the trypsin inhibitor CMTI-III and Asp189 in the substrate pocket of trypsin plays an essential role for the trypsin-inhibitor interaction.  相似文献   

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Despite B. F. Skinner's prominence, his impressive written corpus, and the many authoritative presentations by others of his approach to psychology, the fundamentals of Skinner's psychology have never been addressed in any comprehensive manner. In this article, the authors take steps to fill this gap by synopsizing Skinner's written corpus into 12 fundamental points that seem to characterize his behaviorism. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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This study examines the perceptions of educators about the Drug Abuse Resistance Education (D.A.R.E.) program, based on the results of a statewide survey among 286 fifth and sixth grade teachers and principals. Educators gave their highest ratings to teacher/officer interaction, the role playing exercises, and the graduation ceremony. Ratings of overall program quality and the impact of the program on students were both high. Block regression analysis was used to examine factors predictive of educators' views of D.A.R.E. D.A.R.E. program elements were the most important factors explaining variance in educators' ratings of over-all program quality and program impact on students. Altogether, 54 percent and 38 percent of the variance in both dependent variables were explained. The results are discussed in terms of the important role teachers and principals play as stakeholders in prevention education.  相似文献   

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Diversion colitis is thought to result from nutritional deficiencies secondary to fecal diversion. Symptoms include hemorrhagic purulent rectal discharge, abdominal pain, and tenesmus. 5-Aminosalicylic acid (5-ASA) and N-butyrate enemas have been reported to help this condition non-spinal cord injury (SCI) patients. We report the case of a 49-year-old C6 ASIA B tetraplegic man who had received colostomy because of intractable ileus 10 years earlier. He presented with a 2-week history of rectal pain and bleeding. Abdominal and rectal examination on admission were unremarkable. Colonoscopy showed a partial stricture 70cm proximally to the rectum. The colonic mucosa appeared granular and friable with evidence of linear ulceration. Histopathologic study was consistent with colitis. The patient developed fever, abdominal distention, and extensive retroperitoneal air after endoscopy, suggesting colonic perforation. He was treated with daily 5-ASA suppository and total parenteral nutrition for the presumed diagnosis of diversion colitis, and intravenous antibiotics for perforated colon. After 6 weeks of treatment with 5-ASA, the patient had decreased rectal pain and bleeding. This experience suggests that diversion colitis may be a cause of abdominal discomfort in SCI patients and that 5-ASA may be used in the management of diversion colitis.  相似文献   

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