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101.
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MP Vercauteren HC Coppejans VL Hoffmann V Saldien HA Adriaensen 《Canadian Metallurgical Quarterly》1998,86(5):989-993
In a double-blind, randomized trial, 98 parturients undergoing cesarean section received either hyperbaric or plain bupivacaine 6.6 mg combined with sufentanil 3.3 microg as part of a combined spinal-epidural procedure. To prevent hypotension, 1000 mL of lactated Ringer's solution, 500 mL of hydroxyethyl starch 6%, and ephedrine 5 mg were administered i.v. The height of the block was equal in both groups, but more patients in the plain group had blocks that were either too high or too low (P < 0.01). The number of patients requiring epidural supplementation was equal in both groups. Strict criteria were used to treat hypotension. The overall incidence of systolic blood pressure (<90 mm Hg) was 13%, whereas it was more pronounced in the plain group (21% vs 6% in the hyperbaric group, P < 0.05), which required more ephedrine (P < 0.05) and in which a greater incidence of nausea was noticed (P < 0.05). We conclude that the use of a small dose of intrathecal bupivacaine combined with sufentanil plus our described preloading regimen resulted in a lower incidence of hypotension. Further, we conclude that the use of hyperbaric bupivacaine in this manner provides a more reliable block and a lower incidence of hypotension than plain bupivacaine. Implications: A small dose of hyperbaric bupivacaine 0.5% combined with sufentanil used intrathecally during cesarean section offered a more reliable cephalad spread of the spinal block than the glucose-free combination, which was reflected in a lower incidence of hypotension and nausea. 相似文献
104.
In every-day medical practice, blood relationship of spouses hardly ever play an important part. Mainly for genetic counselors and pediatricians the question of consanguinity of a child's parents arises when either a rare, often hereditary, disorder is diagnosed for the first time in a family, or potential parents want information on the risk for hereditary diseases. A probability calculus based on the corresponding hereditary factors of the joint ancestors establishes how likely homozygotes for hereditary diseases among the offspring of [blood]-related spouses - often cousins of the first or second degree - is. Furthermore, proof of the parents' consanguinity may explain a child's unexpected hereditary disease [especially autosomal recessive disorders] and, at the same time, it means a higher risk of repetition for the affected child's desired siblings. Incest represents a special form of genetic risk; this question arises either in connection with the adoption of a child, which was conceived by an incestuous couple, or with such a child's own family planning later on. Even the parents' descent from an ethnically, politically, religiously or linguistically isolated background may gave a similar impact on the appearance of hereditary disorders: an accumulation of rare genes has to be taken into account; factors causing disorders have to be expected among these genes, too. In the following, all major aspects of the situations described above will be given in detail. 相似文献
105.
R Hoffmann 《Canadian Metallurgical Quarterly》1977,87(2):231-239
The influence of hypoxemia on the brain content of several organic acids and NH+4, AND ITS RELATIONship to the accompanying hypocapnia was studied in unanesthetized rats subjected to hypoxemia for periods ranging between 2 hours and 7 days. Under acute conditions, 'mild' hypoxemia (FO2 = 6--7%), these increases were greater and accompanied by increased gamma-aminobutyric acid (GABA) and decreased glutamic and aspartic acid levels; glutamine and NH+4 remained normal. When hypocapnia was prevented, 'severe' hypoxemia induced only a rise in GABA and slight elevations in lactic and alpha-ketoglutaric acid. During prolonged severe hypoxemia, the effects on the brain amino acids were maintained throughout, indicating that they are independent from the intracerebral pH which should progressively normalize. The effect on lactic acid gradually disappeared. The results show that during hypocapnic hypoxemia the rise in brain GABA is hypoxemia dependent, the decrease in glutamic and aspartic acid is hypocapnia dependent and the increase in lactic acid is in a large way alkalosis dependent. 相似文献
106.
A. R. Hoffmann W. W. Ber G. W. G. Schwarz 《European Journal of Lipid Science and Technology》1976,78(9):367-368
Two-Phase Titration of Anionic Surfactants Using an Improved Stirring Technique The construction of a simple stirred glass vessel in combination with modern metering devices permits two-phase titration of surfactants to be carried out more rapidly and conveniently than so far. Statistical comparisons, based on the mixed indicator titration of anionic tensides, show no differences between this “stirring” method and the established shaking method. 相似文献
107.
Pipe fabrication for the repair sector. The paper discusses the changes in pipe fabrication that have taken place in recent years. These enable repair work to be carried out more efficiently, without thereby impairing the flexibility and speed of operation that are essential to maintenance work. A prerequisite for this is that work on the pipes be transferred to workshops. Only here is it possible for manual operations, such as manual welding, to be reduced to a minimum and be replaced by mechanized or semi-mechanized welding methods. The use of modern machines for bending the pipes is more economic than the welding in of pipe bends. Necking out of the pipes by mechanical means or the use of mechanically pre-fabricated connections permit optimum preparation of the weld seam for branch fittings. Any additional work on the pipes, where this is necessary, is carried out at workplaces specially designed for the purpose. 相似文献
108.
An aus Elektrolyteisen-, Karbonylnickel- und Kupferpulver hergestellten Preßkörpern Untersuchung ihres Sinterverhaltens unter Wasserstoffgas mit Zusätzen von 0,1 und 10 Vol.-% Wasserdampf bei Sintertemperaturen von 870 bis 1200 °C und Sinterdauern von 0 bis 8 h. Messung von Dichte, 0,2-Orenze, Zugfestigkeit und Bruchdehnung der Proben in Abhängigkeit vom Wasserdampfgehalt im Sintergas und dementsprechende thermochemische Deutung der Versuchsergebnisse. 相似文献
109.
The two-photon transition probability between electron energy bands in a semiconductor film is discussed, taking quantum size effects into account. An expression for the absorption rate of one of the two photons is given as a function of the frequency corresponding to all the types of critical points. The anisotropy of non-cubic materials is taken into account. The numerical calculation of the absorption coefficient is performed for the case of ZnS near the extremal point. 相似文献
110.