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61.
In the spherical cells of Escherichia coli rodA mutants, division is initiated at a single point, from which a furrow extends progressively around the cell. Using "giant" rodA ftsA cells, we confirmed that each new division furrow is initiated at the midpoint of the previous division plane and runs perpendicular to it.  相似文献   
62.
Structured lipids containing conjugated linolenic acid (CLNA) were produced separately by enzymatic acidolysis reaction of corn and canola oils (CAO) with bitter gourd (Momordica charantia L) seed oil fatty acids [bitter gourd seed oil fatty acids (BGFA)]. Reactions were conducted using a commercial immobilised sn‐1,3‐specific lipase from Thermomyces lanuginosa (Lipozyme TL IM) in hexane. The effects of reaction time, substrate molar ratio, temperature and enzyme amount on incorporation yield of CLNA were investigated and optimised by response surface methodology with three‐level, two‐factor face‐centred cube design. When reactions were conducted using 10% enzyme for 3 h, the optimum reaction conditions were found for corn oil (CO) as 53.5 °C and 5.9:1 BGFA/CO molar ratio. At these conditions, the incorporation of CLNA into CO was determined as 41.4%. However, CLNA incorporation into CAO was resulted as 37% at optimum conditions which were 54.2 °C and 6.8:1 BGFA/CAO molar ratio.  相似文献   
63.
The authors comment that in the paper of Yuan, Vucetic and Feng (see ibid., vol.47, p.484-87, Apr. 1999), the optimum distance spectrum (ODS) code found for memory order v=5, is actually v=3 convolutional code. The ODS code with h/sub 0/=43/sub s/ and h /sub 1/=55/sub s/ is actually v=3 code, because the feedback polynomial h/sub 0/, and feedforward polynomial h/sub 1/ are not relatively prime polynomials.  相似文献   
64.
Progressive developments in the application of chemical injection have been acquired through out the centuries, starting from the ancient Romans. The method of silica based injection has been employed for a long time and has replaced the polyurethane injection method since the 1970s as a remedy in difficult ground conditions including fractured rock. Currently, various applications of chemical injections are available in civil and mining engineering, including ground stabilization, support anchoring, strata sealing, reduction and diversion of ground water flow and water ingress and creation of a load-bearing ring in tunneling. Drainage of the ground water in the overburden during tunneling will result in an increase in ground settlement by the evacuation of water and closure of the pores in overburden. In this research, the ground water level was decreased to 3 m from the original level and the ground settlement was recorded to reach 25 mm, while the inner tunnel vertical convergence was 6.5 mm after the drainage of 3.5 l/s ground water from the tunnel. Subsequent field measurements and observations indicated that the ground water drainage in the tunnel was reduced to 0–0.5 l/s and the surface settlements were stopped after the chemical injection.  相似文献   
65.
The aim of this study was to document the Doppler indices [pulsatility index (PI) and resistance index (RI)] of the uterine arteries in 30 patients who underwent hysteroscopic rollerball endometrial ablation for dysfunctional uterine bleeding by transvaginal pulsed Doppler sonography, and to reveal whether treatment failures (persistent menometrorrhagia) can be predicted by the blood flow characteristics of the uterine arteries in advance. On the basis of the outcome of patients at the end of the first postoperative year, the Doppler indices of the uterine arteries were meaningful 1 year after the operation when PI (1.32 +/- 0.11; mean +/- SD) and RI (0.71 +/- 0.04) in six menometrorrhagic patients were statistically different from PI (2.19 +/- 0.28; 1.95 +/- 0.36 and 1.82 +/- 0.37) and RI (0.87 +/- 0.06; 0.82 +/- 0.06 and 0.81 +/- 0.04) in normally menstruating, amenorrhoeic and hypomenorrhoeic patients respectively (P < 0.05). On the other hand, the patients who would be menometrorrhagic one year after the operation had a thicker endometrium in the first post-operative month. These findings suggest that the angiogenetic role of the persistent endometrial islands after endometrial ablation needs at some time to be reflected as changes in the Doppler parameters of the uterine arteries.  相似文献   
66.
During a visit to the USSR, an intensive study by the author revealed the broad scope of Soviet research in and development of vacuum metallurgical techniques.  相似文献   
67.
The methanolic extracts of 16 Helichrysum species were investigated for their in vitro antioxidant, radical scavenging and antimicrobial activities. All the extracts showed strong antioxidant and radical scavenging activity. The highest total antioxidant capacity as ascorbic acid equivalents (AAE) of 194.64 mg/g dry extract was obtained for Helichrysum noeanum in the phosphomolybdenum assay. The highest IC50 value (7.95 μg/ml) was observed for the extract of Helichrysum stoechas subsp. barellieri in the DPPH assay. The total phenolic contents of the extracts ranged from 66.74 to 160.63 mg gallic acid equivalents (GAE)/g dry extract. The major component present in the extracts was identified as chlorogenic acid followed by apigenin-7-glucoside and apigenin by HPLC analysis. All the extracts showed significant antimicrobial activity against microorganisms containing 13 bacteria and two yeasts in the agar diffusion method.  相似文献   
68.
Global Media and Cultural Identity in Turkey   总被引:1,自引:0,他引:1  
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69.
Capsella bursa-pastoris (L.) Medic. (shepherd's purse) has been tested as a possible biomonitor of heavy metals in the city of Bradford, UK and compared with Poa annua L. (annual meadow-grass), a species with a similar ecology that had previously been studied for biomonitoring potential. Forty-two sites (urban roadside, urban, urban park, suburban and rural) in and around Bradford were investigated. Concentrations of Pb, Cd, Zn and Cu have been determined in soils and in washed and unwashed plant leaves. Differences between the washed and unwashed samples, reflecting airborne and soil entry routes, respectively, varied according to the metal pollutant. There were significant relationships between the heavy metal concentration in samples of surface soil (depth 0-10 cm) and washed leaves, the concentrations being greater with progressively increased urbanisation of the sites. Capsella bursa-pastoris has been found to be a useful biomonitor of the four heavy metals studied, and it may be a particularly useful species since it could monitor short-term changes in pollution in urban areas.  相似文献   
70.
OBJECTIVE: To analyse the relation between induced abortion and risk of subsequent miscarriage. DESIGN: Case-control study conducted between February 1990 and May 1995. PARTICIPANTS: Case group included 782 women (median age 32 years, range 14-46) admitted for spontaneous abortion (within the 12th week of gestation) to a network of obstetric departments in the greater Milan area. The control group was recruited among women who gave birth at term (> 37 weeks of gestation) to healthy infants on randomly selected days at the hospitals where cases had been identified. A total of 1543 controls (median age 30 years, range 14-45) were interviewed. RESULTS: A total of 102 cases (13%) and 181 controls (12%) reported one or more induced abortions. No clear relation emerged between miscarriage and induced abortions. In comparison with women reporting no induced abortion the odds ratio (OR) for miscarriage were 1.1 (95% CI 0.8-1.4) in women reporting one induced abortion and 0.9 (95% CI 0.4-1.8) in women reporting two or more. Likewise, there was no association between time since last and age at first induced abortion and risk of miscarriage. CONCLUSIONS: This study did not find any strong association between induced and spontaneous abortion.  相似文献   
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