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991.
We have examined the effects of a 5-HT1A receptor agonist (8-hydroxy-2-(di-n-propylamino)tetralin, 8-OH-DPAT) on food preference in ageing rats that had been given a 'palatable' meal 15 min before administration of the drug. Ageing rats consumed a greater amount of the 'palatable' pre-meal than the young rats. In young rats lipids were the predominant source of calories, but in old animals lipid and protein consumption was similar. Administration of 8-OH-DPAT resulted in an increase in total caloric intake in both groups. Concomitant with this there was a significant increase in protein intake in both groups, which was most important in ageing rats, where proteins became the predominant source of calories. 相似文献
992.
OS Bruland O Fodstad M Aas OP Solheim J H?ie A Skretting M Winderen T Michaelsen A Pihl 《Canadian Metallurgical Quarterly》1994,(10):1484-1489
The feasibility of using the murine monoclonal antibody, TP-1, for clinical immunoscintigraphy was examined in a pilot study involving 5 patients with bone sarcomas. 131I-labelled F(ab')2 antibody fragments were injected in doses of 0.8-1.0 mg (90-130 MBq), and the accumulation of radioactivity was examined by scintigraphy, and assessed by direct measurements on biopsied tumour and normal tissue. One osteosarcoma patient had a primary tumour in the femur, whereas the other 4 had single lung metastases detected by other diagnostic methods. Immunoscintigraphy of the femoral primary was optimally visualised after 22 h. In 2 patients, the method failed to detect lung metastasis, in 1 of the cases possibly related to less than optimal methodological conditions. In 2 other patients, increased accumulation of radioactivity indicated one and three lung tumours, in addition to the single metastasis observed by X-ray and CT scanning, tumours that were later confirmed and removed surgically. The concentration of radioactivity in tumour and normal tissues 44-72 h after antibody injection could be measured in 4 patients. The tumour to blood ratios were in the range of 1.2-4.2, compared to 0.1-0.8 for various normal tissues. The results indicate that immunoscintigraphy with TP-1 antibody fragments have a potential for early detection of lung metastases in patients with bone sarcoma. 相似文献
993.
To study the time-course of infectious asthma, we retrospectively examined FEV1 from 5 days before to 10 days after the onset of illness in 31 asthmatic children (20 boys and 11 girls), aged 8 to 12 years. Infections were confirmed by a rise of at least fourfold in serum compliment fixation titers (respiratory syncytial virus, adenovirus, and Mycoplasma pneumoniae) and hemoagglutination inhibition titers (parainfluenza virus types 1, 2, and 3). All the patients had 20 percent or more fall in FEV1 from baseline value during acute phase, but were clinically tolerable and required minimum or no bronchodilators. Regardless of infectious agent, FEV1 began to fall on the first disease day or the previous day, and deteriorate for the first few days. Mean(SD) maximum fall in FEV1 ranged from 39(12) percent to 45(20) percent. Thereafter, FEV1 began to improve and returned to the preillness level by the seventh to tenth day. These results suggest that progressive bronchial obstruction may be inevitable during the acute stage of any infectious asthma. 相似文献
994.
995.
F Buntinx HJ Schouten JA Knottnerus HF Crebolder GG Essed 《Canadian Metallurgical Quarterly》1993,46(4):367-370
The present study was carried out to investigate the biochemical and morphological changes in the liver after ligation of the hepatic artery (HA) in the presence and in the absence of extrahepatic cholestasis (EHC). The study was conducted on 100 rats divided into four groups of 25 animals each: group 1, sham operation; group 2, hepatic artery ligation (HAL); group 3, bile duct ligation (BDL); and group 4, HAL plus BDL. All animals were sacrificed 7 days after surgery when total bilirubin and fractions, alkaline phosphatase (AP), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured in serum and on the inner hepatocyte mitochondrial membrane (IHMM); the incidence of necrosis and the volume fractions of vessels, bile ducts and hepatocytes in the liver were also determined. HAL reduces the relative volumes of bile ducts, with no changes in levels of bilirubin and fractions, AP, ALT, AST and IHMM, but HAL associated with EHC reduces duct proliferation and the liver becomes more vulnerable to necrosis. In conclusion, the normal liver depends on HA flow and this dependence is more evident in the presence of EHC. 相似文献
996.
997.
Anmar W. Sabri Zainab H. Ali Serwan F. Shawkat Lamia A. Thejar Thaer I. Kassim Khalid A. Rasheed 《河流研究与利用》1993,8(3):237-250
The influences of the Samarra impoundment on the ecology of the downstream sector of the river Tigris are investigated. Zooplankton were collected monthly from July 1987 to July 1988. It was found that zooplankton were most abundant during high river discharges in March. During the month of low river discharge, September, the zooplankton population was greatly reduced immediately below the barrage and remained so to the last downstream station. Several factors seem to explain such differences. The high discharge from the impoundment was found to be the dominating factor and may flush the small backwaters in which zooplankton were abundant, thus increasing the population in the river. Zooplankton species vary in their ability to sustain populations in the river, variations which are due mainly to species-specific characteristics. 相似文献
998.
S Knecht M Deppe EB Ringelstein M Wirtz H Lohmann B Dr?ger T Huber H Henningsen 《Canadian Metallurgical Quarterly》1998,29(6):1155-1159
BACKGROUND AND PURPOSE: Since functional transcranial Doppler ultrasonography (fTCD) allows convenient and fully automated quantification of language lateralization, it seems ideal for longitudinal studies of perfusion changes during deterioration as well as recovery of language functions. However, during serial examinations, the technical, stochastic, and physiological variabilities of cerebral blood flow velocities (CBFV) have to be considered. Therefore, before fTCD is accepted as a tool for evaluation of changes in lateralization in the diseased state, its reliability in healthy subjects needs to be determined. METHODS: We performed fTCD during a word generation task based on a previously validated technique with automated calculation of the averaged CBFV differences in the middle cerebral arteries providing an index of lateralization (LI). RESULTS: (1) The accuracy of the LI as assessed by the confidence interval was better than 1% of the mean hemispheric difference. (2) On repeated examination, LIs obtained from 10 subjects showed a high test-retest reproducibility (Pearson product moment correlation coefficient r = 0.95, P < 0.0001). (3) On 10 repeated assessments of LI in the same subject, no practice effects were detected. CONCLUSIONS: Functional TCD is a suitable and very robust tool for the longitudinal quantitative measurement of cerebral language lateralization. 相似文献
999.
MA Lindorfer CS Myung Y Savino H Yasuda R Khazan JC Garrison 《Canadian Metallurgical Quarterly》1998,273(51):34429-34436
The G protein beta5 subunit differs substantially in amino acid sequence from the other known beta subunits suggesting that beta gamma dimers containing this protein may play specialized roles in cell signaling. To examine the functional properties of the beta5 subunit, recombinant beta5 gamma2 dimers were purified from baculovirus-infected Sf9 insect cells using a strategy based on two affinity tags (hexahistidine and FLAG) engineered into the N terminus of the gamma2 subunit (gamma2HF). The function of the pure beta5 gamma2HF dimers was examined in three assays: activation of pure phospholipase C-beta in lipid vesicles; activation of recombinant, type II adenylyl cyclase expressed in Sf9 cell membranes; and coupling of alpha subunits to the endothelin B (ETB) and M1 muscarinic receptors. In each case, the efficacy of the beta5 gamma2HF dimer was compared with that of the beta1 gamma2HF dimer, which has demonstrated activity in these assays. The beta5 gamma2HF dimer activated phospholipase C-beta with a potency and efficacy similar to that of beta1 gamma2 or beta1 gamma2HF; however, it was markedly less effective than the beta1 gamma2HF or beta1 gamma2 dimer in its ability to activate type II adenylyl cyclase (EC50 of approximately 700 nM versus 25 nM). Both the beta5 gamma2HF and the beta1 gamma2HF dimers supported coupling of M1 muscarinic receptors to the Gq alpha subunit. The ETB receptor coupled effectively to both the Gi and Gq alpha subunits in the presence of the beta1 gamma2HF dimer. In contrast, the beta5 gamma2HF dimer only supported coupling of the Gq alpha subunits to the ETB receptor and did not support coupling of the Gi alpha subunit. These results suggest that the beta5 gamma2HF dimer binds selectively to Gq alpha subunits and does not activate the same set of effectors as dimers containing the beta1 subunit. Overall, the data support a specialized role for the beta5 subunit in cell signaling. 相似文献
1000.
H Strenge 《Canadian Metallurgical Quarterly》1998,48(11):457-462
A questionnaire survey was carried out to examine the attitudes of 125 medical students, aged 19-37 years, toward organ donation. 73 of them were in their first semester and 52 senior students in their last year of the study. A return rate of 88% (senior students: 58%) was achieved. Although 59% (71%) expressed willingness to donate their organs, only 30% (50%) had signed an organ donor card. Concerns regarding definition and declaration of death, benefit of organ donation and feelings of the donor's family were identified in 51% (38%) of the students. 71% (79%) had already discussed this issue with their families. In summary, results of the study indicate that more intensified interdisciplinary discussion and information during the study of medicine could bring about an even more positive attitude toward organ donation. 相似文献