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11.
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
12.
Alexander V. Kirdyanov Eugene A. Vaganov Malcolm K. Hughes 《Trees - Structure and Function》2007,21(1):37-44
We propose a technique for separating the climatic signal which is contained in two tree-ring parameters widely used in dendroclimatology.
The method is based on the removal of the relationship between tree-ring width (TRW) and maximum latewood density (MXD) observed
for narrow tree rings from high latitudes. The new technique is tested on data from three larch stands located along the northern
timberline in Eurasia. Correlations were calculated between the temperatures of pentads (five consecutive days), TRW chronologies
and MXD chronologies calculated according to the standard and proposed methods. The analysis confirms the great importance
of summer temperature for tree radial growth and tree-ring formation. TRW is positively correlated with the temperature of
four to eight pentads (depending on the region) at the beginning of the growth season, but MXD as obtained by the standard
technique is correlated with temperature over a much longer period. For maximum density series from which the relationship
between MXD and TRW has been removed (MXD′), there is a clear correlation with temperatures in the second part of the growing
season. These results are consistent with the known dynamics of tree-ring growth in high latitudes and mechanisms of tree-ring
formation. 相似文献
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14.
Summary The batch fermentation kinetics of a novel thermotolerant strain of the yeast Kluveromyces marxianus were evaluated between 30°C and 48°C. The most significant effects of elevated temperature were reductions in overall biomass and ethanol yields. Decreases in the concentration of ethanol attained, and the presence of unutilized substrate suggested increased ethanol inhibition at the higher temperatures studied. 相似文献
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18.
Stephanie Herzfeld 《Plant Systematics and Evolution》1912,62(8-9):289-303
Ohne Zusammenfassung 相似文献
19.
Glycosyl transferases of baby-hamster-kidney (BHK) cells and ricin-resistant mutants. N-glycan biosynthesis 总被引:10,自引:0,他引:10
Five cell lines of ricin-resistant BHK cells have been assayed for gross carbohydrate analysis of cellular glycoproteins, for the activities of several glycosidases and of specific glycosyl transferases active in assembly of N-glycans of glycoproteins. The latter enzymes include sialyl transferase using asialofetuin as glycosyl acceptor, fucosyl transferases using asialofetuin and asialoagalactofetuin acceptors, galactosyl transferases using ovalbumin, ovomucoid and N-acetylglucosamine as acceptors and N-acetylglucosaminyl transferases using ovalbumin and glycopeptides as acceptors. Cell line RicR14, binding less ricin than normal BHK cells, contains reduced amounts of sialic acid, galactose and N-acetylglucosamine in cellular glycoproteins and lacks almost completely N-acetylglucosamine transferase I, an essential enzyme in assembly of ricin-binding carbohydrate sequences of N-glycans. These cells also contain reduced levels of N-acetylglucosamine transferase II active on a product of N-acetylglucosamine transferase I action. Sialyl transferase activity is severely depressed while fucose-(alpha 1 leads to 6)-N-acetylglucosamine fucosyl transferase activity is increased. Cell lines RicR15, 17, 19 and 21 showed partial deficiencies in galactosyl and N-acetylglucosaminyl transferases. A hypothesis is put forward to account for the different carbohydrate compositions and ricin binding properties of glycoproteins synthesised by these cells in terms of the determined enzyme defects, the normal level of sialyl transferases detected in RicR15 and RicR21 cells and the elevated levels of sialyl and fucosyl transferases detected in RicR17 and 19 cells. None of the above changes in glycosyl transfer reactions in the RicR cell lines are due to enhanced glycosidase or sugar nucleotidase activities in the mutant cells. 相似文献
20.
Neil E. Klepeis Suzanne C. Hughes Rufus D. Edwards Tracy Allen Michael Johnson Zohir Chowdhury Kirk R. Smith Marie Boman-Davis John Bellettiere Melbourne F. Hovell 《PloS one》2013,8(8)
Interventions are needed to protect the health of children who live with smokers. We pilot-tested a real-time intervention for promoting behavior change in homes that reduces second hand tobacco smoke (SHS) levels. The intervention uses a monitor and feedback system to provide immediate auditory and visual signals triggered at defined thresholds of fine particle concentration. Dynamic graphs of real-time particle levels are also shown on a computer screen. We experimentally evaluated the system, field-tested it in homes with smokers, and conducted focus groups to obtain general opinions. Laboratory tests of the monitor demonstrated SHS sensitivity, stability, precision equivalent to at least 1 µg/m3, and low noise. A linear relationship (R2 = 0.98) was observed between the monitor and average SHS mass concentrations up to 150 µg/m3. Focus groups and interviews with intervention participants showed in-home use to be acceptable and feasible. The intervention was evaluated in 3 homes with combined baseline and intervention periods lasting 9 to 15 full days. Two families modified their behavior by opening windows or doors, smoking outdoors, or smoking less. We observed evidence of lower SHS levels in these homes. The remaining household voiced reluctance to changing their smoking activity and did not exhibit lower SHS levels in main smoking areas or clear behavior change; however, family members expressed receptivity to smoking outdoors. This study established the feasibility of the real-time intervention, laying the groundwork for controlled trials with larger sample sizes. Visual and auditory cues may prompt family members to take immediate action to reduce SHS levels. Dynamic graphs of SHS levels may help families make decisions about specific mitigation approaches. 相似文献