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991.
TA Gray DB Freedman D Burnett A Szczepura CP Price 《Canadian Metallurgical Quarterly》1996,49(11):903-908
AIM: To survey the use made of laboratory services for urgent tests and clinicians' attitudes to near patient testing. METHODS: A questionnaire was sent to clinicians working in acute hospitals within Trent and North West Thames Regions. RESULTS: 197 replies were received. Most demand came from intensive care units. Overall, clinicians requested a median of six urgent tests a day. Blood glucose and dip stick urine testing were the most commonly performed bedside tests, but 41% of clinicians did not use ward testing. The most frequently cited indication for bedside testing was the need for speed. 85% of clinicians trusted results obtained in their central hospital laboratory, but there was an almost equal division between those who did (34%) and those who did not (38%) trust the results from near patient testing. A slightly larger proportion indicated they would accept responsibility (44%) for results obtained on the ward than would not (35%). Most staff indicated that better transport to the laboratory would remove the need for near patient testing. CONCLUSIONS: Clinicians have demonstrated an apparent need for rapid response testing but there is a strong preference for rapid transport systems and central laboratory analysis rather than bedside testing as a solution to this problem. There is a need to investigate the clinical and cost-effectiveness of near patient testing as a solution to rapid response testing. 相似文献
992.
Findings in 325 consecutive primary seminal analysis done at the Infertility Treatment Centre of IPGMR, are discussed. The clinical profile of the infertile couples was recorded. Semen was examined for quantity, sperm density, motility and morphology. An attempt was also made to correlate past illnesses with the quality of semen. 65 patients (20%) showed azoospermia, while 29 (8.9%) showed sperm count of less than 10 million/ml. History of past illnesses which contribute to azoospermia/oligospermia was obtained in 46% of azoospermia cases compared to only 10% in subjects showing sperm count of over 10 million/ml. Commonest association between azoospermia and past illness was found in the case of small-pox, where out of 31 subjects with past history of small-pox, 15 showed complete azoospermia, one showed sperm density of less then 10 million/ml. 相似文献
993.
Structure and architecture of the bacterial virus fd. An infrared linear dichroism study 总被引:1,自引:0,他引:1
Oriented gels of intact bacterial virus fd have been invetigated by infrared linear dichroism. Infrared absorption band maxima and dichroism indicate an alpha-helix content of the major coat protein of 95-100%. The alpha-helical rods of the coat protein are aligned parallel to the long axis of the virion with an inclination roughly estimated to approximately 37 degree. The presence of DNA infrared bands at 968, 885, 830 and 799 cm-1, the absence of a band at 860 cm-1 and the perpendicular polarization of the symmetric PO-2 stretching vibration at 1085 cm-1 are all indicative of a B-type backbone conformation in the single-stranded DNA. We find no evidence for specific interaction between aromatic side groups (phenylalanine, tyrosine) and the DNA bases. Our results independently confirm most features of the model of Marvin and co-workers [2,15 ] based on low-resolution X-ray diffraction studies. However, our findings contradict their suggestion of an A-type DNA in the bacterial virus fd. Two results are consistent with rigid and stable order in the virus. First, over a 4-day period, 65% of the peptide hydrogens remain unexchanged with deuterium. Second, changes in the relative humidity of the sample do not result in any shifts in the DNA spectrum that are characteristic of free DNA. 相似文献
994.
A simple, general method for purifying restriction endonucleases is described. The method employs precipitation of nucleic acids from crude extracts with polyethyleneimine followed by affinity chromatography on columns of heparin covalently linked to agarose. Most of the sixteen enzymes tested could be purified to a degree sufficient for DNA sequencing work by this method sometimes supplemented by at most one step of ion exchange chromatography. 相似文献
995.
996.
By means of the light and electron microscopy, construction and architectonics of neurons in the cat thalamus medio-dorsal nucleus are described. Differences in the neuronal body dimentions, their form, number of deferent dendrites and character of axonal branching made it possible to define 3 types of neurons. Applying the method based on retrograde axonal transport of exogenous horse-radish peroxidase, it was demonstrated that neurons of type II, contrary to the existing opinion, send their axons into the prefrontal cortex and, hence, are associative-projective. Ultrastructural difference of axonal terminals, differences in the form and size of synaptic vesicles made it possible to reveal 5 types of presynapses. 相似文献
997.
998.
999.
ES Sarkkinen MI Uusitupa H Gylling TA Miettinen 《Canadian Metallurgical Quarterly》1998,47(6):744-750
Serum noncholesterol sterols, cholesterol precursors and plant sterols, are indicators of cholesterol absorption and synthesis. Serum plant sterol concentrations correlate positively with cholesterol absorption, but have also been found to correlate with dietary unsaturated to saturated fatty acid ratios. We studied the concentration of serum noncholesterol sterols during four different fat-modified diets, (1) high-fat, saturated fat-enriched (control), (2) reduced-fat, sunflower oil-enriched (SO-enriched), (3) rapeseed oil-enriched (RO-enriched), and (4) reduced-fat, saturated fat-enriched (reduced-fat), followed for 6 months in hypercholesterolemic subjects in a parallel design. The proportion of lathosterol (micrograms per 100 mg cholesterol), a precursor of cholesterol synthesis, increased significantly (P < .05) in both SO-enriched (mean +/- SD 147 +/- 57 v 167 +/- 76, 0 v 6 months) and RO-enriched (147 +/- 54 v 157 +/- 52) groups, where the reduction in low-density lipoprotein (LDL) cholesterol was also significant. The proportion of sitosterol, a plant sterol, decreased significantly in the control group (137 +/- 48 v 122 +/- 42), and the proportion of another plant sterol, campesterol, increased in the RO-enriched group (280 +/- 141 v 333 +/- 162), reflecting changes in the use of vegetable oils in these two groups rather than increased cholesterol absorption. In the whole study population, the proportion of linoleic and alpha-linolenic acid (a marker of the use of RO) in cholesterol esters (CEs) correlated (P < .001) with the proportion of sitosterol (r = .43) and campesterol (r = .36) in serum at the end of the study. In conclusion, serum cholesterol precursors were found to be useful indicators of cholesterol metabolism, but changes in serum plant sterols reflected dietary changes rather than cholesterol metabolism during long-term dietary intervention with fat-modified diets. 相似文献
1000.
TA King GJ Cederbom JL Champaign DH Smetherman JS Bolton GH Farr WM McKinnon RR Kuske GM Fuhrman 《Canadian Metallurgical Quarterly》1998,176(6):497-501
To evaluate whether the type of weight-bearing loading subjected to the skeleton during horseback-riding was associated with differences in bone mass and muscle strength of the thigh, we investigated bone mass and isokinetic muscle strength in 20 female horse riders (age 17.9 +/- 0.6 years) who were riding 7.0 +/- 3.4 hours/week, and 20 nonactive females (age 17.8 +/- 1.1 years). The groups were matched according to age, weight, and height. Areal bone mineral density was measured in total body, head, lumbar spine, right femoral neck, Ward's triangle, and trochanter, the whole dominant and nondominant humerus, and in specific sites in the right femur diaphysis, distal femur, proximal tibia, and tibia diaphysis using dual X-ray absorptiometry. Isokinetic concentric and eccentric peak torque of the quadricep and hamstring muscles were measured using an isokinetic dynamometer. There were no significant differences in bone mass between the horseback riders and nonactives at any site measured. The horse riders were significantly (P < 0.05-0.01) stronger in concentric hamstrings strength at 90 degrees/second and 225 degrees/second and in eccentric quadricep and hamstring strength at 90 degrees/second. Horseback riding in young females is associated with a high muscle strength of the thigh, but not with a high bone mass. 相似文献