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991.
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Joke van Welzen Alex M. van Herk Anton L. German 《Macromolecular chemistry and physics.》1987,188(8):1923-1932
The structural behaviour of cobalt(II)phthalocyanine-tetrasodium sulfonate (CoPc(NaSO3)4) ( 1 ), a catalyst used in thiol oxidation, was investigated in the presence of ionenes (poly-quaternary ammonium salts), ( 2 ) using visible light spectroscopy. It was observed that ionenes, which have been shown to promote the catalytic activity, strongly enhance the aggregation of the cobalt complex. No cobalt site isolation occurred up to N+/Co = 105. Furthermore, a stoichiometric CoPc(NaSO3)4/ionene complex appeared to be formed with an N+/Co-ratio of 4:1. This ratio was found to hold for ionenes with M?n varying from 6 100 to 22 000 and charge densities from 0,8 to 1,5. As the charge density was increased, the observed CoPc(NaSO3)4 spectrum was more affected. Experiments with oxygen in alkaline solution revealed that the complex was resistant toward oxygen adduct formation in the presence of ionenes. This phenomenon is discussed in relation to the catalytic activity of the system. 相似文献
995.
Physicians as gatekeepers. A complex challenge 总被引:1,自引:0,他引:1
M D Reagan 《The New England journal of medicine》1987,317(27):1731-1734
996.
F. Berndsen D. Arvidsson L.-K. Enander C.-E. Leijonmarck U. Wingren C. Rudberg S. Smedberg G. Wickbom A. Montgomery 《Hernia》2002,6(2):56-61
Interest in inguinal hernia surgery has increased significantly with the introduction of new operating techniques during
the past decade. This multicenter study compared short-term results in patients treated by the laparoscopic transabdominal
preperitoneal patch technique (TAPP; n=518) and the Shouldice technique (n=524). We evaluated demographics, operative data, complications, hospital stay, postoperative pain, use of analgesics, functional
status, sick leave, and complaints up to 3 months postoperatively. The median operating time was shorter in the Shouldice
group (55 vs. 65 min), but there were no significant differences in complication rates, and major complications were rare.
The hospital stay was 1 day or less in over 98% of cases in both groups, but more operations were performed on outpatient
basis in the Shouldice group. In the TAPP group postoperative pain and analgesic consumption were less, postoperative functional
status was better, and sick leave was shorter (10 vs. 14 days). These results show that the two methods are equally safe and
have few major complications. The TAPP operation is associated with less postoperative pain, better postoperative functional
status, and shorter sick leave, but at the price of a longer operating time.
Electronic Publication 相似文献
997.
998.
999.
D. F. Shepeli 《Pharmaceutical Chemistry Journal》2005,39(8):428-432
Salmus is a product of Salvia sclarea technology that is widely used in balneary practice. It is established that the analytical characteristics of salmus substance,
as stipulated in the temporal pharmacopoeial article VFS 42-1530-85, are not objective and should not be used for evaluating
the quality of the ready-to-use preparation and for monitoring the process of its manufacturing. TLC data show that salmus
contains all components of sage oil (Russian State Standard GOST 3171-76) except for linalyl acetate. Qualitative specific
color reactions on Silufol TLC plates showed for the first time the presence of flavonoids such as kaempferol, quercetin,
juglanin, quercitrin, and rungioside and revealed one previously unknown substance, probably, of a flavonoid nature. The TLC
data also showed the presence of condensed tannins and chlorophylls. It is suggested to perform quantitative analysis and
identification of biologically active substances in salmus using methods for determining the content of reducing sugars (carbohydrates)
and oxidizable components. New procedures for determining the sum of essential oils and flavonoids using the total content
of extractable components have been developed and verified. It is suggested that these substances are among the main therapeutic
components of salmus.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 39, No. 8, pp. 33 – 36, August, 2005. 相似文献
1000.
Tc-99m HMPAO was used to evaluate cerebral perfusion in a patient with tuberous sclerosis. The SPECT images demonstrated reduced HMPAO uptake in regions corresponding with MRI-confirmed locations of cortical tubers. These results indicate that the lesions are characterized by vascular perfusion deficits and support the hypothesis that cortical tubers result from developmental abnormalities of the embryonic central nervous system. 相似文献