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991.
Reinaldo B Bestetti José Roberto Costa Marot Ulysses B Stella Luiz A P Finzi 《Cardiovascular pathology》2003,12(3):163-165
A 52-year-old man presented with heart failure of 1 month duration. He had undergone aortic valve and root replacement 30 months before admission. A continuous murmur was heard in the second intercostal space at the parasternal border. Aortography showed a pseudoaneurysm surrounding the aorta, whereas color Doppler study revealed flow from the central aorta to the pseudoaneurysm and flow from the pseudoaneurysm to the pulmonary artery trunk through a fistulous communication between them. Thus, fistulous communication with pulmonary artery causing heart failure is a complication of pseudoaneurysm after aortic and root replacement, which can be diagnosed clinically and echocardiographically. 相似文献
992.
Arancha C Ruíz-Llorente S Cascón A Osorio A Martínez-Delgado B Benítez J Robledo M 《Journal of human genetics》2002,47(4):190-195
Until now, the study of the multiple endocrine neoplasia type 1 (MEN1) gene in patients suspected of having the disease was expensive and laborious due to the large size of the gene. We have
optimized the conformation-sensitive gel electrophoresis (CSGE) technique to analyze by four rather simple multiplex PCR reactions,
and a single electrophoresis run, the entire coding region of the MEN1 gene, plus the exon–intron boundaries. This improvement of the CSGE technique was confirmed as an effective procedure for
screening for the MEN1 gene by detecting ten previously known MEN1 gene mutations and four polymorphisms. The MEN1 gene of 12 patients with unknown mutations was then screened, and an abnormal CSGE profile was identified in 10/12 cases.
Subsequent DNA sequencing demonstrated 3 of them to be novel mutations (E45K, 4479delACAG, 6073insC) and 7 to have been previously
reported; in the remaining 2 patients, we confirmed the absence of any alteration of the coding sequence of MEN1. Mutation screening of the MEN1 gene using CSGE was demonstrated to be a fast, simple, and inexpensive method to study patients suspected of having MEN1
disease.
Received: November 29, 2001 / Accepted: January 28, 2002 相似文献
993.
Toussaint O Remacle J Dierick JF Pascal T Frippiat C Royer V Chainiaux F 《Mechanisms of ageing and development》2002,123(8):937-946
994.
Using a specific radioimmunoassay technique it seems that Prostacyclin (PG-I2) has a strong effect on the cyclic nucleotide content of the rat gastric (fundic) mucosa. 1 min after an intragastric application of 100 g/kg PG-I2 the cAMP-content and in the 5th min the cGMP-content showed a highly significant decrease. It seems that the basic mechanism of action of PG-I2 is a typical hit and run effect, acting on the intracellular second messenger system. 相似文献
995.
Rubem Carlos Araujo Guedes Romualdo José do Carmo 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1980,39(3):341-349
Summary The ionic composition of the internal environment was altered in rabbits by means of gastric washing, combined with intramuscular administration of 3-Beta-aminoethylpyrazole. The effects of this treatment on cortical spreading depression (SD) were studied. C1- and Na+ concentrations decreased significantly in serum and in cerebrospinal fluid after the treatment. This made the animals much more susceptible to SD, as established by the high incidence of spontaneous SD, increased SD velocity of propagation and facilitated its interhemispheric transfer. An intensification of the epileptiform activity associated with SD was also observed. Intravenous replacement of NaCl abolished the above effects on SD. When the intravenous replacement was done with Na-Isethionate, those effects were enhanced. It is concluded that chloride deficiency was the main factor responsible for the observed facilitating effects.This work was supported by grants from the BNDE (FUNTEC-74 e 143), CNPq and CAPES 相似文献
996.
E. Obál Jr. G. Benedek A. Jancsó-Gábor F. Obál 《Pflügers Archiv : European journal of physiology》1979,382(3):249-254
Salivary thermolytic mechanism (weight of salivary glands, effect of desalivation on water intake and body temperature, grooming activity) as well as escape behaviour and reaction to heat pain were studied in capsaicin-desensitized and control rats exposed to various warm ambient temperatures. Body temperature of the desensitized rats increased more than the controls at all the ambient temperatures studied (32, 34 and 36°C); however, significant differences in the mechanism of salivary cooling were obtained only at 34 and 36°C. Central impairment of saliva spreading in desensitized rats seems evident. Complete surgical desalivation did not increase hyperthermia of control and desensitized animals in warm environments. Therefore other mechanisms, primarily vasodilatatory, must also be involved in the rat's thermolytic normal response. Although desensitized rats did not show a tendency to escape from the warm environment their response to heat pain was normal. In conclusion, it is suggested that heat perception in desensitized animals is impaired; however, the existence of some capsaicin-insensitive thermolytic mechanisms (prone extension of the body) cannot be excluded.Supported by the Scientific Research Council, Ministry of Health, Hungary /4-05-0303-04-2/0/ and MTA-OM-MÉM-EÜM 70.211/79 相似文献
997.
Dr Bernard Sénécail Bernard Menanteau Pierre Quereux 《Surgical and radiologic anatomy : SRA》1979,2(2):181-190
Résumé Ce travail tente de définir une écho-anatomie du foie normal à partir de neuf plans tomographiques de référence, chacun étant caractérisé par la morphologie de la glande hépatique, par son contenu structural et par son environnement topographique.Les auteurs interprètent l'imagerie échographique directement à partir de l'observation macroscopique de coupes anatomiques correspondantes. Ils indiquent que la corrélation anatomo-échographique est satisfaisante et dégagent quelques indications spécifiques pour chacune des incidences. 相似文献
998.
999.
Quantification of Human Immunodeficiency Virus Type 1 RNA Levels in Plasma by Using Small-Volume-Format Branched-DNA Assays 总被引:2,自引:0,他引:2 下载免费PDF全文
Torange Yeghiazarian Yuqi Zhao Stanley E. Read William Kabat Xiaoyi Li Sarah J. Hamren Patrick J. Sheridan Judith C. Wilber David N. Chernoff Ram Yogev 《Journal of clinical microbiology》1998,36(7):2096-2098
We have developed small-volume (50 or 250 μl)-format branched-DNA assays for human immunodeficiency virus type 1 (HIV-1) RNA for use with specimens in which the volume is limited and/or a high viral load is anticipated. These formats exhibited good correlation with the standard 1-ml format; high specificity, reproducibility, and linearity; and no significant difference in the quantification of HIV-1 subtypes. 相似文献
1000.
José M. González-García Carmen Antonio José A. Suja Julio S. Rufas 《Chromosome research》1996,4(2):124-132
We have determined the number and location of the nucleolar organizing regions in spermatocytes ofGraphosoma italicum (2n=12A+ XY/XX) by means of silver impregnation, chromomycin A3/distamycin A staining and fluorescencein situ hybridization. The identification of only one nucleolar organizing region located at one of the X chromosome ends has provided a suitable cytological marker to analyse the segregation of this univalent and that of the XY pseudobivalent during the first and second meiotic divisions respectively. Our results clearly show that at first meiotic metaphase the chromatids of the X chromosome are orientated with their long axes perpendicular to the polar axis. Although the kinetic activity is restricted to only one end in both X chromatids during the first meiotic division, both ends of the same chromatid have the same probability of showing such kinetic activity. In this sense, we also report that the chromatid segregation maybe initiated either at the same sister chromatid ends or at opposite ends in each chromatid. Thus, this indicates a sex chromatid independence as regards to the chromatid segregation during the first meiotic division. Throughout the second meiotic division both ends of the X chromatid are involved with the same probability in the end-to-end association to conform the XY pseudobivalent. This also implies a random localization of the kinetic activity at the ends opposite to those involved in the end-to-end association.accepted for publication by J. S. (Pat) Heslop-Harrison 相似文献