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MIu Shchelkanov NG Iaroslavtseva AN Iudin IuA Mirskov VF Eremin LP Titov PG Rytik EV Karamov 《Canadian Metallurgical Quarterly》1998,43(5):220-229
Immunoreactivity of sera obtained in 1996 from HIV-1-infected intravenous narcomaniacs from an epidemic focus in Gomel region, Belarus, is studied with a panel of 10-16-component synthetic peptides simulating apical epitope of surface glycoprotein gp120 V3 loop of HIV-1 variants. Comparative analysis of resultant spectra with representative immunoreactivity spectra of sera from a sampling of HIV-1-positive sera collected in 1986-1997 in different regions of the former USSR demonstrated a high homogeneity of immunoreactivity spectra of sera from Gomel region. Serotypes of HIV-1 A/C variants circulating in populations of intravenous narcomaniacs in the focus in Gomel region in 1996 and in Southern and South-Eastern Ukraine in 1995-1996 are similar. This confirms a previous conclusion about the prevalence of A/C serotype among intravenous narcomaniacs in the former USSR. 相似文献
104.
L Alvarez MY Rios C Esquivel MI Chávez G Delgado MI Aguilar ML Villarreal V Navarro 《Canadian Metallurgical Quarterly》1998,61(6):767-770
Two new cytotoxic isoflavans, (3S)-7-hydroxy-2',3',4',5', 8-pentamethoxyisoflavan (1) and (3S)-3',7-dihydroxy-2',4',5', 8-tetramethoxyisoflavan (2), were isolated from the bark and trunks of Eysenhardtia polystachya (Leguminosae), together with the known constituents stigmasterol, isoduartin, cuneatin, 7-hydroxy-2',4', 5'-trimethoxyisoflavone, and 3,4-dimethoxy-8, 9-(methylenedioxy)pterocarpan. The structures of 1 and 2 were elucidated on the basis of spectroscopic methods. The antimicrobial, cytotoxic, and insecticidal potential of some of these compounds were evaluated. The isoflavans 1, 2, and isoduartin (2', 7-dihydroxy-3',4',8-trimethoxyisoflavan) displayed moderate cytotoxic activity against KB cell lines. 相似文献
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LA Baltina SA Ryzhova EV Vasil'eva GA Tolstikov GM Sakhautdinova FS Zarudi? 《Canadian Metallurgical Quarterly》1994,20(12):1365-1374
Triterpene glycopeptides, derivatives of glycyrrhizic acid, were synthesized with the use of tert-butyl esters of L-amino acids. The condensation of glycoside with esters was carried out with N-hydroxysuccinimide--N,N-dicyclohexylcarbodiimide or N-hydroxybenzotriazol--N,N'-dicyclohexylcarbodiimide in the presence of a base (triethylamine, N-methyl- or N-ethylmorpholine). The protection groups were removed with the use of trifluoroacetic acid. 相似文献
108.
AM Sartori MH Lopes LA Benvenuti B Caramelli A di Pietro EV Nunes LP Ramirez MA Shikanai-Yasuda 《Canadian Metallurgical Quarterly》1998,59(5):784-786
We report a human immunodeficiency virus (HIV)-infected man with chronic Chagas' disease who developed a congestive heart failure that could not be clinically controlled. Endomyocardial biopsy revealed severe myocarditis and the xenodiagnosis result was positive, but Trypanosoma cruzi by direct microscopic examination of the blood was found only four months after the symptoms had started. Treatment with benznidazole was effective in reducing parasitemia, stabilizing the clinical status, and controlling tissue damage related to the parasite. Although the finding of T. cruzi trypomastigotes by direct microscopic examination of the blood has been considered the mark of Chagas' reactivation in immunocompromised patients with chronic disease, in this case it was a late finding. 相似文献
109.
EV Benevolenskaya GL Kogan AV Tulin D Philipp VA Gvozdev 《Canadian Metallurgical Quarterly》1997,44(6):646-651
INTRODUCTION: Acute scrotum in the pediatric age is mainly related to surgical causes. Spermatic cord torsion and inguinoscrotal hernia must be ruled out first, because of the possible ischemic damage to gonadal tissue and therefore surgery is sometimes performed directly, thus representing also a diagnostic tool. Spermatic cord torsion is found in two age ranges, namely: the neonatal period, where it usually represents the evolution of an intrauterine process, and the peripubertal period, which is more frequent. An unquestionable and prompt diagnosis is particularly needed because of the extreme sensitivity of gonadal tissue to ischemia. In this particular field, color and power Doppler US, depicting gonadal flow, have greatly increased diagnostic imaging capabilities, which were previously limited to B-mode US. MATERIAL AND METHODS: We examined 19 peripubertal patients with the diagnosis of spermatic cord torsion made on the basis of B-mode US and then confirmed with color Doppler. RESULTS: We found two signs which can be considered highly suggestive of spermatic cord torsion: the spiral twist of spermatic vessels and the peculiar extent of reactive hydrocele, caused by the bell clapper anomaly of the vaginal sac. CONCLUSIONS: The above US patterns are very helpful to diagnose spermatic cord torsion. 相似文献
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