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801.
H. E. Webb 《BMJ (Clinical research ed.)》1992,304(6837):1260-1261
802.
The chromosomes of the D genome of wheat and the genome R of rye can be distinguished at meiosis by C-banding in triticale-wheat hybrid plants. All members of both genomes almost exclusively formed univalents at metaphase I. However, at anaphase I the frequencies of equationally dividing chromosomes were higher for rye than for wheat chromosomes. The differential centromere behaviour at anaphase I is ascribed to differences in the time at which wheat and rye univalents are formed during the first meiotic prophase. 相似文献
803.
From six to 89 months after surgery 82 patients who had been treated by radical surgery (118 excisions) for intractable hidradenitis suppurativa were reviewed. Local recurrence rates varied greatly with the disease site, being low after axillary (3%) and perianal surgery (0%) and high after inguinoperineal (37%) and submammary (50%) excision. Recurrence results from inadequate excision or an unusually wide distribution of apocrine glands, but physical factors such as obesity, local pressure, and skin maceration played a part in a few patients. Recurrence due to inadequate surgery tended to be the most troublesome. At follow up 75 (91%) of the patients were pleased with the results of their operation. A quarter of the patients developed disease at a new anatomical site after operation. Radical surgery gives good symptomatic control of severe hidradenitis suppurativa of the axilla, inguinoperineal, and perianal regions but is less satisfactory for submammary disease. 相似文献
804.
Stability of o-phthalaldehyde-derived isoindoles 总被引:1,自引:0,他引:1
The degradation of 1-alkylthio-2-alkylisoindoles, generated in situ by reaction of o-phthalaldehyde with primary alkylamines in the presence of selected thiols, was studied under conditions typical of those used in precolumn derivatization applications. In all cases, loss of isoindole followed pseudo first order kinetics and was strongly accelerated by excess o-phthalaldehyde in the reaction mixture. Reactivity toward o-phthalaldehyde was found to be influenced by a number of experimental parameters including thiol structure, thiol concentration, amine structure, solvent composition, and pH. In the absence of excess o-phthalaldehyde, the stability of all derivatives examined was excellent. These results provide a basis for optimization of reaction conditions for maximum derivative stability. 相似文献
805.
806.
Ovarian cancer G protein-coupled receptor 1 (OGR1) is a proton-sensing molecule that can detect decreases in extracellular pH that occur during inflammation. Although OGR1 has been shown to have pro-inflammatory functions in various diseases, its role in autoimmunity has not been examined. We therefore sought to determine whether OGR1 has a role in the development of T cell autoimmunity by contrasting the development of experimental autoimmune encephalomyelitis between wild type and OGR1-knockout mice. OGR1-knockout mice showed a drastically attenuated clinical course of disease that was associated with a profound reduction in the expansion of myelin oligodendrocyte glycoprotein 35-55-reactive T helper 1 (Th1) and Th17 cells in the periphery and a reduced accumulation of Th1 and Th17 effectors in the central nervous system. We determined that these impaired T cell responses in OGR1-knockout mice associated with a reduced frequency and number of dendritic cells in draining lymph nodes during EAE and a higher production of nitric oxide by macrophages. Our studies suggest that OGR1 plays a key role in regulating T cell responses during autoimmunity. 相似文献
807.
A E Sukhov G M Cha?chenko 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》1989,39(5):828-835
In experiments on 56 healthy subjects (18-20 years old) the quality of their activity was determined during compensatory watching the mark at complicating regimes of work. Depending on the difficulty of the task five groups of subjects were singled out with optimum working capacity in one of four working conditions: normal, ordinary and strenuous work, model of stress situation. It is established that the change of the number of significant correlative connections between main parameters of psychophysiological state of man-operator reflects the condition of his functional systems. On the basis of computation of total range of organization values of both R-R intervals of the ECG and duration of expiration, the success of the man-operator work in complex conditions of activity is predicted. 相似文献
808.
809.
810.
The critical weed-free period in organically-grown winter wheat 总被引:1,自引:0,他引:1
J P WELSH H A J BULSON C E STOPES R J FROUD-WILLIAMS A J MURDOCH 《The Annals of applied biology》1999,134(3):315-320
Two experiments were conducted in central southern England between September 1994 and August 1996 to identify the critical weed-free period in organically grown winter wheat (Triticum aestivum, cv. Mercia). In competition with a mixed weed infestation of predominately Alopecurus myosuroides and Tripleurospermum inodorum it was found that wheat yield decreased as the duration of the weed-infested period increased and that the crop needed to be kept free of weeds from sowing in order to completely avoid any yield loss. Also, weeds emerging in the wheat crop (predominately T. inodorum) during the growing season had a significant and detrimental effect on yield. The existence of the critical period, therefore, depends on the imposition of an acceptable yield loss. If a 5% yield loss gives a marginal benefit compared with the cost of weed control, the critical period will begin at 506°C days after sowing (November) and end at 1023°C days after sowing (February). This information could be used by farmers to target mechanical weeding operations to control weeds at a time that will have maximum benefit to the crop. 相似文献