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71.
In this study the desizing, scouring, bleaching and slack mercerising of cotton fabric by a one–step process at different sodium hydroxide concentrations, impregnation temperatures and curing times were examined. The results indicate that when the fabrics are mercerised at lower temperature, the strength retention and colour strength are enhanced. When the sodium hydroxide concentration is increased, these properties also increase. When cotton fabrics are mercerised for 3 min at 40C and cured for 30 s at 120C, their physical properties are similar to those obtained using a conventional two–step approach.  相似文献   
72.
INTRODUCTION: Global amnesia (AG) is a dysfunction of memory, in which there is a sudden incapacity to remember recent events and assimilate new information. The aetiology is currently under discussion. The main hypotheses under consideration are an ischemic mechanism and an epileptic mechanism. OBJECTIVE: To study the cerebral blood flow in patients with temporary global amnesia (AGT) or permanent global amnesia (AGP) using functional neuroimaging techniques. MATERIAL AND METHODS: Four patients were studied. Two had severe alterations of fixation memory which had been present for months. The other two had a sudden loss of recent memory, although space-person orientation and immediate memory remained normal. In all cases the cerebral blood flow (FSC), was assessed by single photon emission tomography (SPECT), using Tc-HMPAO as the radio tracer. RESULTS: We describe 4 patients, 2 men and 2 women aged between 42 and 64.2 with AGT and the others with AGP. On SPECT there was temporal hypoperfusion in all 4 patients. In 2 cases there was associated parietal hypoperfusion and in 1 case there was frontal hypoperfusion. CONCLUSIONS: These findings suggest that AGT and AGP are of vascular origin and that SPECT is a useful diagnostic technique in patients with AG.  相似文献   
73.
The western region of Saudi Arabia is an area with a high prevalence of urolithiasis. This study was designed to find the effect of climatic changes on the occurrence of urinary stone colic as well as the effect of Ramadan fasting and pilgrimage festival. The emergency room (E.R.) records at King Abdulaziz University Hospital in Jeddah were studied for 3 consecutive years. Males diagnosed as urinary colic during this period were recorded on monthly basis with correction for 30 days a month. Data were recorded before, during and after the fasting month as well as before and after the pilgrimage festival. The results showed a steady increase in urinary stone colic in the hot season with a maximum rate in the months of June, July and August. The mean number of males with stone colic in these months was 45.33, 44.19 and 45.16 respectively. The lowest number was in March (28.06) with a rate of 4.11 per 1000 patients. A strong correlation was found between urinary stone colic and both temperature and atmospheric pressure with a P value of < 0.0001. No significant correlation was observed with relative humidity and similarly no significant change in relation to Ramadan fasting or the pilgrimage festival. These results suggest that there is a clear stone season in this area corresponding to the hot summer months. No significant increase in urinary stone colic was observed in relationship to the fasting month of Ramadan or the pilgrimage festival.  相似文献   
74.
Fine fractions of aggregate crushed from Finnish Precambrian crystalline bedrock were studied by determinining the particle size distribution with a Sedigraph particle size analyzer, specific surface area using the nitrogen adsorption method and porosity with a mercury porosimeter. According to abrasion resistance (Los Angeles) and brittleness (Swedish impact) values, all the materials studied were suitable as road aggregate. Roads where material with high specific surface area were used however soon proved to suffer from frost damage. No correlation between specific surface area and values of abrasion and brittleness were found. The specific surface area also proved to depend on the quality rather than the quantity of the fine fractions. Presence of clay minerals tends to increase the sp.s.a. Thus, in addition to the quantity also the quality of fine fractions must be analysed in road aggregate material.  相似文献   
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76.
Currant oils have special health properties due to their moderate contents of α‐linolenic, γ‐linolenic and stearidonic acids. The distribution of fatty acids (FA) in the triacylglycerols (TAG) may affect the beneficial effects. Seed oils of wild northern red currant (NRC) (Ribes spicatum L.) from Northern Finland and of wild alpine currant (AC) (R. alpinum L.) from the South‐West coast of Finland were investigated. The purified TAG were analysed by tandem mass spectrometry by applying the ammonia negative ion chemical ionisation – collision‐induced dissociation method. Molecular weight fractions rich in C18:3 FA and C18:4 FA were investigated. Of the total oil, the molecular weight species 54:7 (ACN:DB), 54:8 and 54:9 were more abundant in NRC than in AC, being 21.0%, 15.8%, 7.4% and 16.2%, 11.2%, 4.8%, respectively (p <0.05). The species 52:6 was more abundant in AC (3.1%) than in NRC (2.6%) (p <0.05). The preferential order of FA to be in the sn‐2 position in both berries was typically C18:1 > C18:2 > C18:4 > C18:3. No difference was observed between relative locations of C16:0 FA and C18:3 FA in either of the oils. Within the TAG consisting of FA combinations C18:3/C18:3/C18:1 (54:7), C18:1 was more preferentially in the sn‐2 position (p <0.05) in AC (93.2%) than in NRC (74.6%), and in the case of C18:3, the preference was vice versa. Within the molecular weight species 54:9, FA combination C18:4/C18:3/C18:2, linoleic acid preferentially occupied the secondary position (p <0.005) in both berries, and the proportion of the TAG regioisomer pair sn‐C18:3‐C18:4‐C18:2 + sn‐C18:2‐C18:4‐C18:3 was more abundant (30.2%) in NRC than in AC (15.3%). Within the TAG species 52:6, proportions of all the existing combinations, C16:0/C18:3/C18:3, C16:0/C18:4/C18:2 and C16:1/C18:3/C18:2, varied between the two berry species (p <0.005).  相似文献   
77.
78.
The gyrA gene of Campylobacter fetus subsp. fetus, which encodes the A subunit of DNA gyrase, was cloned, and its nucleotide sequence was determined. An open reading frame of 2,586 nucleotides which encodes a polypeptide of 862 amino acids with an Mr of 96,782 was identified. C. fetus subsp. fetus GyrA is most closely related to Campylobacter jejuni GyrA, with 73% homology at the nucleotide level and 78% identity between polypeptides. The next most closely related GyrA was that from Helicobacter pylori, with both DNA homology and amino acid identity of 63%. The gyrA and gyrB (DNA gyrase B subunit) genes were located on the genomic map of C. fetus subsp. fetus ATCC 27374 and shown to be separate. A clinical isolate of C. fetus subsp. fetus and a laboratory-derived mutant of ATCC 27374, both resistant to ciprofloxacin, had identical mutations within the quinolone resistance determining region. In both mutants a G-->T transversion, corresponding to a substitution of Asp-91 to Tyr in GyrA, was linked to ciprofloxacin resistance, giving MICs of 8 to 16 micrograms/ml.  相似文献   
79.
Amputation surgery should be approached as the first step in the rehabilitation of a patient with a non-functioning, salvageable limb. Before performing amputation surgery, the rehabilitation team should have an understanding of outcome expectations for the individual patient. Biologic joints are energy couples. When performing amputation surgery, more proximal amputations, accompanied by the removal of more joints, decreases the ability of patients to walk and live independently. Functional outcome appears to increase with the length of the residual limb.  相似文献   
80.
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