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131.
132.
Control of experimental autoimmune encephalomyelitis by T cells responding to activated T cells 总被引:21,自引:0,他引:21
T cell vaccination against experimental autoimmune disease is herein shown to be mediated in part by anti-ergotypic T cells, T cells that recognize and respond to the state of activation of other T cells. The anti-ergotypic response thus combines with the previously shown anti-idiotypic T cell response to regulate autoimmunity. 相似文献
133.
Gaschen L Kircher P Lang J Gaschen F Allenspach K Gröne A 《Veterinary journal (London, England : 1997)》2005,169(2):242-250
In this pilot study, we hypothesize that waveform patterns of the celiac and cranial mesenteric arteries differ pre- and post-prandially in normal dogs compared to those with chronic enteropathy. We further suggest that it is possible to classify these findings according to the type of disease present. Eleven dogs with chronic enteropathy and eight normal dogs were examined. Doppler examinations were performed at times 0 (fasted), and at 20, 40, 60 and 90 min post-prandially. The waveform shapes were described and the following features were extracted: resistive and pulsatility index, mean maximum velocity, mean diastolic velocity, peak systolic velocity, early diastolic notch ratio and the deceleration time interval. Dogs with inflammatory bowel disease had either lower or absent flow at fasting in early diastole compared to the other groups. Resistive and pulsatility indices decreased during digestion in all groups except those with protein losing enteropathy. The increase in mean diastolic flow during digestion in affected dogs was either lacking (protein-losing enteropathy) or significantly lower (inflammatory bowel disease, P<0.05) compared to normal dogs. Dogs with chronic enteropathies had abnormal arterial waveform shapes and suboptimal increases in diastolic blood flow during digestion and these findings worsened with the severity of the histological lesions present. Doppler ultrasound of the celiac and mesenteric arteries has great potential to enhance our understanding of intestinal disease in conscious dogs. 相似文献
134.
OBJECTIVE: To compare the efficacy of 0.3% stabilized glutaraldehyde and alcohol (SG+A), 0.3% SG and water (SG+W), and 4% chlorhexidine gluconate tincture (CG+A), as skin disinfectants in dogs undergoing ovariohysterectomy. STUDY DESIGN: Prospective, blinded clinical study. ANIMALS: One hundred and twenty-one dogs. METHODS: Cutaneous bacterial colony forming units (CFU) from the perioperative site after skin preparation, after antisepsis, and after surgery (incisional and paramedian), were quantified. The influence of high initial bacterial counts (> or =150 CFU) and surgical time on antibacterial efficacy was examined and the proportion of dogs from which Staphylococcus intermedius was cultured, determined. Perioperative skin reactions and wound infections were documented. RESULTS: All 3 antiseptic solutions significantly and equally reduced CFU to all post-antisepsis sampling levels irrespective of surgical duration (mean surgical times 151.6, 136.2, and 149.6 minutes for CG+A, SG+A and SG+W, respectively). Median percentage reductions in CFU ranged between 99.3% and 100%. In dogs with initial high counts and disinfected with CG+A and SG+W, the incisional samples had significantly higher counts than the post-antisepsis samples. In the CG+A and SG+W groups, the proportion of post-surgery samples yielding S. intermedius was significantly higher at the incisional than the paramedian sites. Eight mild cutaneous reactions were recorded in equal proportions for the 3 solutions. There were no recorded infections. CONCLUSIONS: All 3 preparations had an equal ability to reduce and maintain low CFU counts, with minimal cutaneous reactions. CLINICAL RELEVANCE: SG solutions are safe and effective preoperative skin antiseptics for elective clean-contaminated surgical procedures. 相似文献
135.
Daley DO Rapp M Granseth E Melén K Drew D von Heijne G 《Science (New York, N.Y.)》2005,308(5726):1321-1323
The protein complement of cellular membranes is notoriously resistant to standard proteomic analysis and structural studies. As a result, membrane proteomes remain ill-defined. Here, we report a global topology analysis of the Escherichia coli inner membrane proteome. Using C-terminal tagging with the alkaline phosphatase and green fluorescent protein, we established the periplasmic or cytoplasmic locations of the C termini for 601 inner membrane proteins. By constraining a topology prediction algorithm with this data, we derived high-quality topology models for the 601 proteins, providing a firm foundation for future functional studies of this and other membrane proteomes. We also estimated the overexpression potential for 397 green fluorescent protein fusions; the results suggest that a large fraction of all inner membrane proteins can be produced in sufficient quantities for biochemical and structural work. 相似文献
136.
Joachim Katzur Klaus Fischer Lutz Böcker Karin Tonder Cathrin Liebner 《Archives of Agronomy and Soil Science》2013,59(6):647-661
In Langzeit-Inkubationsversuchen wurden die Auswirkungen abgestufter Mengen von chemisch veränderter (N-modifizierter) Braunkohle auf die mikrobiologischen und enzymatischen Unsatzleistungen in verschiedenen Kippsubstraten geprüft. Die Untersuchungsbefunde charakterisieren diesen Humusdüngestoff als ein dauerhaft wirksames organisches Bodenverbesserungsmittel mit N-Düngewirkung, das die bodenmikrobiologischen Aktivitäten verbessert. 相似文献
137.
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139.
Mlamuli M. Motsa Cecilia Bester Margaretha M. Slabbert Karin Hannweg Mardé Booyse 《Genetic Resources and Crop Evolution》2018,65(6):1711-1724
Cyclopia (honeybush) species are widely-used in the production of a South African herbal tea and are endemic to the fynbos region of the Western and Eastern Cape Provinces. Honeybush is still one of the orphan agriculture crops and recent breeding efforts by researchers are hampered by the lack of basic genetic information e.g. basic chromosome numbers and ploidy levels. This study determined nuclear DNA content and ploidy level of various genotypes of three Cyclopia species using flow cytometry and cytological counting of chromosomes. Nuclei analysis of young leaves of C. genistoides, C. longifolia and C. subternata were done using a flow cytometer, while root tip squashes were carried out in order to correlate flow cytometry results. Flow cytometry analysis indicated differences in the nuclear DNA content among and within species whilst the DNA ploidy level only differed among species. Cyclopia genistoides had a higher DNA ploidy level (≥?10C) and DNA content (10.63 pg) than C. longifolia (6.09 pg) and C. subternata (5.99 pg), with no differences observed between the ploidy level of the latter two species (6C). The inferred ploidy level from nuclear DNA content by flow cytometry was consistent in all 30 genotypes of C. longifolia, and 24 of the 25 C. subternata and in only four of the 15 C. genistoides studied genotypes. These findings are important in breeding new cultivars with desired horticultural traits, thus improving the commercial characteristics for the sustainable production of honeybush. 相似文献
140.
Christoph Buksnowitz Christoph Hackspiel Karin Hofstetter Ulrich Müller Wolfgang Gindl Alfred Teischinger Johannes Konnerth 《Wood Science and Technology》2010,44(3):389-398
Electronic speckle pattern interferometry was applied to directly measure the distribution of longitudinal, tangential, and
shear strains in small boards of Norway spruce (Picea abies (L.) Karst.) exposed to tensile load in longitudinal direction. A sample with a central intergrown knot and one with an equivalent
loose knot were compared with reference samples made of clear wood with an artificial central circular or square hole, respectively.
The observed measurements were compared with a finite element (FE) simulation. The FE model was based on a geometric model
to quantify the local fibre orientation and a micromechanical model to estimate elastic constants of clear wood and knot tissue.
Both the measurements and simulation clearly illustrate a rather homogenous strain distribution around the intergrown knot.
In comparison, the natural optimisation of dispersing strain peaks is less efficient in the case of loose knots. The artificial
circular and square holes in samples with parallel fibre orientation lead to high gradients in the strain field and peak values
in vicinity of the disturbance. 相似文献