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1.
Dopamine receptors influence vasoactive intestinal peptide release from turkey hypothalamic explants
Amongst the elements which contributed to the success of the early lung transplants at the beginning of the 1980's we feel that the careful selection of candidates probably played a predominant role. If some of the selection criteria initially described remain somewhat intangible, others have either been eased or have been invalidated. The experience acquired over the last 15 years has enabled to precise the optimal moment to include patients on the waiting list and to refine the choice for the type of surgical procedure according to the underlying disease. This article aims to review the different selection criteria for candidates for transplantation and stresses those which have recently undergone change. 相似文献
2.
OM Elashry G Giusti RB Nadler EM McDougall RV Clayman 《Canadian Metallurgical Quarterly》1997,158(2):363-369
The choline-containing phosphoglycolipid, MfGL-II, is the major polar lipid of Mycoplasma fermentans PG18. Anti-MfGL-II antisera raised in rabbits using the purified MfGL-II as an immunogen were employed in immunogold electron microscopic and immunofluorescence studies showing that MfGL-II is uniformly distributed and exposed on the cell surface of M. fermentans cells. The specificity of the antibodies was determined by immunostaining of lipid extracts separated by thin layer chromatography. The antibodies recognize lipids specific to M. fermentans but did not cross-react with lipid extracts of M. penetrans, M. capricolum, M. gallisepticum or Acholeplasma laidlawii. As phosphocholine almost completely abolished antibody interaction with MfGL-II in an ELISA assay it is suggested that the anti-MfGL-II repertoire is composed primarily of anti-phosphocholine antibodies. The anti-MfGL-II antisera inhibit the attachment of M. fermentans to Molt-3 lymphocytes suggesting that MfGL-II plays a major role in M. fermentans-host cell interaction. 相似文献
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OM Takayanagui AA Castro e Silva RC Santiago NS Odashima VC Terra AM Takayanagui 《Canadian Metallurgical Quarterly》1996,54(4):557-564
Cysticercosis is a severe public health problem in several regions of Asia, Africa and Latin America. Epidemiologic studies based on the frequency of cases observed in specialized neurology, neurosurgery and computed tomography services, at autopsy and in seroepidemiologic studies do not permit the determination of the true prevalence of the disease in the population. The objective of the present study was to investigate the prevalence of cysticercosis by compulsory notification. The coefficient of prevalence was 54 cases/100,000 inhabitants in the municipality of Ribeir?o Preto. The results also indicated that cysticercosis is not under control in our region since 21% of cases presented the active form of the disease. Compulsory notification proved to be a valuable resource for the epidemiologic study of cysticercosis, also permitting the mapping of more affected areas for a better direction of prevention strategies. 相似文献
5.
AJ Dorta M Ferra R Bu-Colfiu L García M Gil X Escobar G Martín NA Díaz OM Perez MT Interián 《Canadian Metallurgical Quarterly》1993,10(10):490-491
It is essential to know how the immune system acts in different neurological diseases, some of them non very well known or of unknown etiology at all. It was applied Reiber and Felgenhauer's formula in 56 patients with different diseases. IgA, IgM, IgG and albumin were quantified in sera and cerebrospinal fluid by simple immunodiffusion. It was observed more frequent IgG local synthesis and IgA in this sample. 相似文献
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Mary J. Garson Mary P. Zimmermann Christopher N. Battershill Janet L. Holden Peter T. Murphy 《Lipids》1994,29(7):509-516
The tropical marine spongeAmphimedon terpenensis (family Niphatidae, order Haplosclerida) has previously been shown to possess unusual lipids, including unusual fatty acids.
The biosynthetic origin of these fatty acids is of interest as the sponge supports a significant population of eubacterial
and cyanobacterial symbionts. The total fatty acid composition of the sponge was analyzed by gas chromatography/mass spectrometry
of the methyl esters. Among the most abundant of the fatty acids in intact tissue were 16∶0, 18∶0 and 3,7,11,15-tetramethylhexadecanoic
(phytanic) acid. In addition, three brominated fatty acids, (5E,9Z)-6-bromo-5,9-tetracosadienoic acid (24∶2Br), (5E,9Z)-6-bromo-5,9-pentacosadienoic acid (25∶2Br) and (5E,9Z)-6-bromo-5,9-hexacosadienoic acid (26∶2Br) were also present. The three brominated fatty acids, together with phytanic acid,
were isolated from both ectosomoal (superficial) and choanosomal (internal) regions of the sponge. Analysis of extracts prepared
from sponge/symbiont cells, partitioned by density gradient centrifugation on Ficoll, indicated that phytanic acid and the
three brominated fatty acids were associated with sponge cells only. Further, a fatty acid methyl ester sample from intact
tissue ofA. terpenensis was partitioned according to phospholipid class, and the brominated fatty acids were shown to be associated with the phosphatidylserine
and phosphatidylethanolamine fractions that are commonly present in marine sponge lipids. The phosphatidylcholine and phosphatidylglycerol
fractions were rich in the relatively shorter chain fatty acids (16∶0 and 18∶0). The association of brominated long-chain
fatty acids (LCFA) with sponge cells has been confirmed. The findings allow comment on the use of fatty acid profiles in chemotaxonomy
and permit further interpretation of LCFA biosynthetic pathways in sponges. The assignment of the sponge studied, which is
currently placed asA. terpenensis, is being supported to some extent, but the species is unusual in having C25 fatty acids as the major constituent in this group. Other factors, such as season or microenvironmental conditions, may influence
observed fatty acid composition which tends to reduce the usefulness of fatty acid profiles as markers in sponge chemotaxonomy. 相似文献
8.
OBJECTIVE: The effect of cigarette smoking on gallbladder (GB) emptying and refilling after a fatty meal was examined in 10 healthy volunteers (four women and six men, mean age 27.6 yr). METHODS: On three different days, the subjects underwent in randomized order: a control test without smoking (C), or they smoked two cigarettes during the early (0-20 min; S0-20), or late (20-40 min; S20-40) phase of the meal-induced GB emptying. GB volumes were measured ultrasonographically before the meal and at 10, 20, 30, 40, 60, 90, 120, 150, and 180 min postprandially. Two-way ANOVA was applied for statistical assessment of the results. RESULTS: The fasted GB volumes amounted to 15.7 +/- 1.8 cm3 (C), 15.0 +/- 1.7 cm3 (S0-20), and 18.4 +/- 2.3 cm3 (S20-40), F2;18 = 1.524, NS. Maximum GB emptying was observed until 60 min after the meal, with a nadir of the GB volume amounting to 7.3 +/- 1.3 cm3 (C), 6.6 +/- 1.2 cm3 (S0-20), and 7.1 +/- 1.1 cm3 (S20-40). No significant difference was found between the stimuli tested when absolute GB volumes were considered: F2;180 = 2.725, NS. Analysis of the GB emptying-refilling curves normalized for the fasted GB volume revealed that a significant inhibitory effect was produced by smoking two cigarettes during the late phase of GB emptying on the subsequent GB refilling: F2;162 = 11.066, p < 0.001 for the whole curve, and F2;72 = 7.126, p < 0.005 for the refilling phase. A significant contrast was found next between S20-40 and the control day (p < 0.001 whole curve; p < 0.005 refilling phase only), as well as between S20-40 and S0-20 (p < 0.001 whole curve; p < 0.025 refilling phase only). CONCLUSION: We conclude that smoking two cigarettes does not disturb the fatty meal-induced GB contraction in healthy humans. Subsequent GB refilling is delayed if smoking takes place during the late phase of the postprandial GB contraction. 相似文献
9.
10.
OM Horbatiuk 《Canadian Metallurgical Quarterly》1998,(4):25-27
The study was made of labyrinthine changes induced by lasix dehydration. Changes indicative of Meniere's disease were identified at comparison of the findings obtained by audiological lasix test, caloric optokinetic reactions. Four types of the nystagmic response in the bithermal lasix-test were determined. These reactions are helpful for more precise staging of the disease. 相似文献