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81.
Daily injections of amphetamine during 3 weeks into the rat caudal and rostral neostriatum impaired avoidance conditioning of rats in shuttle box. The data obtained suggests involvement of both parts of the neostriatum's dopaminergic system in avoidance conditioning and complex behavioural actions in rats. 相似文献
82.
Translated from Izmeritel'naya Tekhnika, No. 10, p. 31, October, 1991. 相似文献
83.
A Weishaupt R Gold S Gaupp G Giegerich HP Hartung KV Toyka 《Canadian Metallurgical Quarterly》1997,94(4):1338-1343
Exposure of T cells to their specific antigen normally results in proliferation, but in the presence of high and repeatedly administered doses of antigen, T cells may undergo apoptosis. Here we demonstrate that i.v. administration of as little as 100 microg of recombinant P2 protein twice daily completely prevents experimental autoimmune neuritis induced by adoptive transfer of neuritogenic P2-specific T cells or by immunization with the neuritogenic P2-peptide-spanning amino acids 53-78. Antigen treatment started after disease onset markedly ameliorated experimental autoimmune neuritis. The mechanism of action may be through programmed T cell death; a profound increase of the rate of apoptosis was seen in inflammatory foci of peripheral nerves and in the spleen. There was no cytokine switch by our Th1 cells after exposure to their specific antigen, but increased secretion of interferon gamma and tumor necrosis factor alpha was demonstrated. High antigen dose therapy using recombinant, pathogen-free protein may prove useful for the treatment of autoimmune inflammatory disorders of the nervous system. 相似文献
84.
BACKGROUND: This study examined the efficacy and safety of retrograde cardioplegia in comparison with an antegrade/retrograde approach. METHODS: Between January 1, 1991, and December 31, 1995, 7,032 coronary artery bypass procedures, alone or in combination with valve replacement/repair, were performed using either retrograde cardioplegia (R) or an antegrade/retrograde (AR) approach. There were 4,224 patients in the R group and 2,808 in the AR group. These included elective, urgent, emergent/salvage, first operative, and redo cases. RESULTS: All preoperative, intraoperative, and postoperative variables listed in The Society of Thoracic Surgeons National Cardiac Surgery Database were used to compare the two groups using univariate analysis. The pump time was longer in the AR group, with fewer grafts per patient. The R group had higher predicted risk (3.2% versus 3.0%; p = 0.04), more postoperative atrial fibrillation (34% versus 31%; p = 0.006), and longer postoperative length of stay (8.8 versus 8.0 days; p < 0.001). Using The Society of Thoracic Surgeons National Cardiac Surgery Database predicted risk group model, a subgroup of 221 coronary artery bypass grafting patients in the retrograde (s-R) and 132 coronary artery bypass grafting patients in the antegrade/retrograde (s-AR) group fell into a greater incidence of predicted mortality group (> or = 10%). The s-R subgroup had more patients in New York Heart Association functional class IV. Univariate analysis revealed higher postoperative atrial fibrillation (51% versus 41%; p = 0.05) and longer postoperative length of stay (12.8 versus 10.8 days; p = 0.03) in the s-R subgroup versus the s-AR subgroup. CONCLUSIONS: The results appear to favor neither approach. Preoperatively, both retrograde groups (R and s-R) had higher preoperative predicted risk, but operative mortality or complications were not significantly increased when compared with the AR and s-AR groups. Retrograde cardioplegia alone was shown to be effective in the R and s-R groups, but atrial fibrillation developed in more patients, which could have contributed to longer length of stay in these groups. Antegrade/retrograde cardioplegia offers good immediate outcome but the delivery method can be cumbersome and confusing during the adjustments of flow clamps for antegrade/retrograde delivery and may contribute to prolonged pump times. From this retrospective, nonrandomized review, it appears that retrograde cardioplegia alone provides as good myocardial protection and safety as an antegrade/retrograde approach in either the low-risk or high-risk patient. 相似文献
85.
86.
KN Srinivasan KV Pugalendi G Sambandam M Ramakrishna Rao S Krishnan VP Menon 《Canadian Metallurgical Quarterly》1998,275(2):197-203
Between 1957 and 1993, the Siberian Chemical Complex (Tomsk-7) located in the Tomsk region (Russia) regularly discharged radioactive liquid wastes into the Tom River which resulted in an extensive contamination of large territories with long lived radionuclides such as cesium-137 and strontium-90. In the summers of 1996 and 1997, Research Team of Siberian Medical University conducted biodosimetry and cytogenetic monitoring of pikes (Esox lucius) caught in the Tom River at various distances downstream from the Siberian Chemical Complex (SCC) using the micronucleus test and the gamma spectroscopy. Our findings demonstrated that the difference in frequency of micronucleated erythrocytes between the radiation-exposed fish caught downstream from the SCC and the controls was statistically significant (P < 0.01). Moreover, we found a good correlation between radiocesium concentration and micronucleated erythrocyte frequency in pikes. It was found that both the micronucleated erythrocyte frequency in pike blood and the level of the pike radiocesium concentration depended on the age of pikes. The micronucleated erythrocyte frequency gradually increased from the 1-year-old pikes to the over 20-year-old pikes. On the other hand, the average level of radiocesium concentration gradually increased from the 1-year-old pikes only up to the 10-year-old pikes. There is no correlation between radiocesium concentration and micronucleated erythrocyte frequency in the over 10-year-old pikes. 相似文献
87.
88.
We determined the nucleotide sequences of Norwalk-like viruses in 10 PCR products from stool or oyster specimens obtained from four outbreaks of gastroenteritis in which shellfish was suspected as the cause in Shizuoka prefecture in Japan between 1987-94. The sequences were determined from nucleotide positions 4561-4852 (292 bp) in the polymerase region. Two types of sequences were detected. One (genotype 1) had 87% sequence homology with the prototype Norwalk virus, and the other (genotype 2) had 59% sequence homology. The sequences from isolates belonging to the same genotype were almost the same regardless of the year of isolation. Because sequences of 2 genotypes were detected in 2 of the 4 outbreaks, nested PCR was performed with genotype-specific primers to detect the presence of 2 genotypes in the same specimen. In 5 of 10 specimens, PCR bands were detected with both genotype-specific primers, indicating the coexistence of 2 genotypes in 1 specimen. We also detected two genotypes of Norwalk-like virus in an oyster from a sample implicated in one of the outbreaks which may provide direct evidence of oysters as the cause of the gastroenteritis. 相似文献
89.
IuV Grachev ML Kukushkin AP Sudarikov VF Zhuravlev MIu Gerasimenko 《Canadian Metallurgical Quarterly》1998,98(11):4-8
45 patients were observed in the periods of both acute herpes zoster and postherpetic neuralgia (PHN). In most of the patients herpetic eruptions were located in the areas of innervation of the first branch of the trigeminal nerve. In acute period of the disease there were used aciclovir, helepin or alpisarinum, antiherpetic immunoglobulin, deoxyribonuclease, non-narcotic analgetics were used. Of 28 patients residual PHN was observed in 6 cases, delayed PHN (during 3 months)--in 2 patients. The PHN development was characteristic for elderly patients, delayed request for medical care, concomitant diseases, eruptions with hemorrhagic component and secondary pyodermia and considerable residual sensory deficit. In therapy of PHN the most effective drugs were amitriptylin, non-narcotic analgetics, anticonvulsants as well as acupuncture and electroacupuncture. Relief of a typical deafferentation of pain syndrome was achieved by means of ultrasonic destruction of the trigeminal nucleus (one case). Early therapy of acute herpes zoster does not prevent completely PHN development, but it decreased considerably probability of its forming as well as the severity of its course. 相似文献
90.