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61.
G Horne A Jamaludin JD Critchlow DA Falconer MC Newman J Oghoetuoma EH Pease BA Lieberman 《Canadian Metallurgical Quarterly》1998,13(11):3045-3048
Insemination with donor spermatozoa is an integral part of infertility treatment. For the last 3 years in our unit, intrauterine insemination with donor spermatozoa (IUID) has been used in preference to vaginal insemination. In this retrospective study, patients were offered an initial course of five single intrauterine inseminations with cryopreserved donor spermatozoa and treatment was then reviewed. A total of 389 patients received 1465 inseminations. In all, 1119 cycles were monitored using luteinizing hormone serum analyses and 346 cycles using the urine home test kits. The clinical pregnancy rate per insemination for the cycles monitored by the serum assay was 18.0% (202/1119) compared with the urine cycles (13.7%, 46/346) (P <05). The pregnancy loss rate was not significantly different (14.4%, 29/202 and 21.7%, 10/46) (serum and urine cycles respectively). The viable clinical pregnancy rate was significantly higher (P <03) for the serum cycles than for the cycles using the urinary monitoring (15.5%, 173/1119 and 10.4%, 36/346 respectively). The cycles monitored by serum assay had a significantly higher cumulative viable clinical pregnancy rate (P <0001) of 70.2% after nine inseminations compared with the urine monitored cycles of 54.8%. The majority of patients opted for the serum cycles, with a minority self-selecting the urine cycles mainly for travelling convenience. The explanation for the significant differences between the viable clinical pregnancy rates per insemination and the cumulative viable clinical pregnancy rates may be due to the sensitivity of the urine home test kit or the patients' interpretation of the result. 相似文献
62.
For quantum-dot cellular automata molecular electronic devices, one of the fundamental tasks is to arrange the molecules on a surface in a controlled manner. In this report, we discuss a molecular lift off technique to form nanopatterns toward the development of molecular circuits. In our molecular lift off technique, we use electron beam lithography to form nano-trenches on a polymethylmethacrylate (PMMA) film on a SiO2 wafer. This wafer is soaked in a Creutz-Taube ion [(NH3)5Ru(pyrazine)Ru(NH3)5](o-toluenesulfonate)5 (CT5) aqueous solution. After residual PMMA removal, atomic force microscopy is used to investigate the resulting surface. Thirty-five nanometer CT5 lines are demonstrated on a SiO2 surface. Compared with other molecular nanopatterning techniques, ours is both economical and capable of high-resolution. 相似文献
63.
The use of normal Raman spectroscopy and surface-enhanced Raman spectroscopy (SERS) of cationic-coated silver and gold substrates to detect polyatomic anions in aqueous environments is examined. For normal Raman spectroscopy, using near-infrared excitation, linear concentration responses were observed. Detection limits varied from 84 ppm for perchlorate to 2600 ppm for phosphate. In general, detection limits in the ppb to ppm concentration range for the polyatomic anions were achieved using cationic-coated SERS substrates. Adsorption of the polyatomic anions on the cationic-coated SERS substrates was described by a Frumkin isotherm. The SERS technique could not be used to detect dichromate, as this anion reacted with the coatings to form thiol esters. A competitive complexation method was used to evaluate the interaction of chloride ion with the cationic coatings. Hydrogen bonding and pi-pi interactions play significant roles in the selectivity of the cationic coatings. 相似文献
64.
In this paper, immobilization of gold colloidal particles onto amine-modified magnetic microparticles is demonstrated. Once immobilized, the gold was then reacted with pentachlorothiophenol (PCTP) to form a self-assembled monolayer. The PCTP-gold colloid on magnetic microparticles was then used to extract naphthalene from aqueous samples. A magnet was used to concentrate the microparticles onto the side of the sample vial, allowing detection of naphthalene by surface-enhanced Raman spectroscopy. Using the PCTP-gold colloid on magnetic microparticles the limit of detection for naphthalene achieved was 0.3 microg mL(-1). Multiple extractions can be done with the PCTP-gold colloid on magnetic microparticles to further lower the detection limit. 相似文献
65.
Maier Steven F.; Anderson Christine; Lieberman David A. 《Canadian Metallurgical Quarterly》1972,81(1):94
Shocks which cannot be controlled by an organism have been shown to interfere with subsequent escape-avoidance training more than do equivalent shocks which can be controlled. 2 experiments extended the generality of this phenomenon by examining the effects of the escapability of shock on subsequent shock-elicited aggression. Exp. I (with 48 male Sprague-Dawley rats) found that prior exposure to inescapable shock reduced the frequency of shock-induced fighting, while escapable shock did not produce such a reduction. The theory that yoked-control procedures can capitalize on individual differences and produce a systematic difference between groups was ruled out as an explanation of the data of Exp. I by the results of Exp. II, conducted with 22 similar Ss. (19 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
66.
Outgassing experiments have been performed on a variety of polyacrylonitrile- and rayon-based carbon yarns. Major residual impurities, as well as those introduced from surface treatments, have been identified. Sulphur has been shown to be a major impurity of rayon-based carbon fibres, with concentrations up to 3110 ppm by weight having been determined by neutron-activation analyses. Removal of this contaminant as a volatile material commences at approximately 1300° C. Interrelationships between sulphur removal and mechanical and crystallographic properties have been considered for one rayon-based carbon yarn. Decreases in both interlayer spacing and tensile strength are associated with sulphur evolution, whereas apparent crystallite size and Young's modulus are unaffected by the outgassing. 相似文献
67.
68.
Examined the most effective usage of videotape in job interview skill training for 24 mentally retarded young adults utilizing the microcounseling model of instruction. Seven (e.g., open- and closed-ended questions and reflection of content) skill areas were modeled to 3 experimental groups for 6 sessions where the method of videotape utilization differed for each group. Data reveal that the microcounseling model is most effective with the 2 skill areas of eye contact and body posture regardless of the method of videotape utilization. Significant differences occurred in both of these skill areas after modeling Session 2 and remained significant throughout the study. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
69.
A Palant V Deutsch Y Kishon Y Lieberman JH Yahini HN Neufeld 《Canadian Metallurgical Quarterly》1976,38(10):1086-1091
Two patients with pulmonary hydatid embolization are described and commented upon in the light of 43 similar published cases. The diagnosis was strongly suspected from the medical history and the chest x-ray films and supported by angiocardiography. The angiocardiographic features of this condition have not been described previously in detail. They include amputation and filling defects of pulmonary artery branches, which are typically located proximal to a rounded tumour-like opacity seen on the plain x-ray film. Both patients underwent successful embolectomy. 相似文献
70.
DM Lieberman 《Canadian Metallurgical Quarterly》1976,82(6):939-940
One hundred sixty-nine adult patients admitted to McPherson Hospital for elective eye or ear, nose, and throat surgery had erythrocyte sedimentation rates (ESRs) performed by the Wintrobe method, in addition to the usual admission laboratory work. The patients were selected for study if they had no known disease or were not receiving any medication that affects the sedimentation rate. The results showed that the mean ESR rose with each decade of life. 相似文献