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521.
After reviewing the reports ofHistoplasma capsulatum in man, animal and soil, and the results of histoplasmin sensitivity tests in Europe, we have concluded that autochthonous histoplasmosis is present but rare in Europe.Only the European parts of Turkey and of U.S.S.R. are considered in this report.Paper read at the Eighth International Congresses for Tropical Medicine and Malaria, September 1968, Teheran (Iran). 相似文献
522.
In the genus Bacillus (Insecta, Phasmatodea) the Bag320 satellite DNA
family is present in the bisexual B. grandii and in the related automictic
nonhybrid B. atticus; it is lacking in the other bisexual taxon of the
genus, B. rossius. This family of highly repeated sequences was analyzed
for 11 populations of the apomictic triploid hybrid B. lynceorum. In the
neighbor-joining dendrogram, B. lynceorum nucleotide sequences distribute,
regardless of geographical origin, among two clusters, one also including
all clones of the three B. atticus races, and the other including sequences
of the B. grandii grandii subspecies. Thus, B. lynceorum is a trihybrid
taxon: as the molecular approach definitively demonstrates, it embodies one
haploid complement each of both B. grandii grandii and B. atticus, which
must be added to that of B. rossius. The contribution of the latter species
has already been assessed on karyological and allozymic grounds. A
statistical analysis performed on p-distances shows that for the parental
taxa, nucleotide substitution values are of comparable magnitudes at the
population level but differ at the subspecific level, being higher for the
bisexual taxon. In the apomictic hybrid, atticus- and grandii grandii- like
sequences coexist with significantly different p-distance values. For three
clones, the nucleotide compositions at the diagnostic loci suggest that
gene conversion can occur between atticus- and grandii grandii-like
monomers. On the whole, this supports bisexuality as a driving force in
variant fixation and suggests that in Bacillus, different gametogenetic
processes and different origins of the unisexuals are mirrored in genomic
turnover rates of satellite DNA.
相似文献
523.
Mantovani G. Macciò A. Lai P. Turnu E. Del Giacco G. S. 《Cell biochemistry and biophysics》1994,24(1-3):301-305
The aim of the study was to evaluate the subset distribution and the IL-2 R p55–p75 subunit expression on unstimulated and
phytohemagglutinin (PHA)-stimulated (at 3-d) peripheral blood mononuclear cells (PBMC), of patients with solid cancers of
different sites. Indeed the expression of the two subunits of IL-2R is an essential prerequisite for The action of the IL-2
on CD8+, CD16+ lymphocytes as effectors in antitumor activity (LAK-cells). The subset distribution (CD3, CD4, CD8, CD16, DR) was assessed
by cytofluorometry with specific monoclonal antibodies (MAbs); the p55 (CD25) and p75 subunit expression was evaluated by
specific MAb (OKT26a and anti-p75). Ninety patients with advanced cancer (mainly non-small cell lung cancer [NSCLC], head
and neck cancer, and gynecological cancer; mean age 55 yr; range 27–80) were studied. Thirty-five age- and sex-matched healthy
subjects were studied as controls. Our data show that there is no significant difference in the subset distribution between
cancer patients and controls. Furthermore, no difference has been found in the expression of p55 subunits on unstimulated
PBMC between cancer patients and controls. No difference has been found in the expression of both p55 and p75 subunits on
PHA-stimulated PBMC between cancer patients and controls. Our results can support the rationale for further clinical trials
with IL-2 in solid malignancies. 相似文献
524.
525.
526.
F.J. Benati F. Lauretti L.C. Faccin B. Nodari D.V. Ferri M.S. Mantovani R.E.C. Linhares C. Nozawa 《Letters in applied microbiology》2009,49(6):791-795
Aims: Chlorophyllin (CHLN), a synthetic derivative of chlorophyll, was assayed in the replication of poliovirus (PV-1) and bovine herpesvirus (BoHV-1) in HEp-2 cell cultures.
Methods and Results: Virucidal activity of CHLN was evaluated and the time-of-addition assay was performed as follows: before the infection (−1 and −2 h), at the time of the infection (0 h) and after the infection (1 and 2 h). Plaque reduction assay (PRA) showed that CHLN inhibited BoHV-1 and PV-1 infection and the 50% inhibitory concentrations (IC50 ) against BoHV-1 and PV-1 infection were 8·6 and 19·8 μg ml−1 , respectively. The time-of-addition study demonstrated that the CHLN was effective inhibiting viral replication in 51% and 66·5% for PV-1 and BoHV-1, respectively, at the highest concentration of 20·0 μg ml−1 , when added during the infection. The directed effect of CHLN on viral strains demonstrated an inhibition of 62% and 66·4% for PV-1 and BoHV-1, respectively, by PRA.
Conclusions: These results demonstrated that CHLN could be used as an antiviral suggesting directed activity on virus particles and on virus-receptor sites to BoHV. For poliovirus, CHLN also demonstrated virucide activity, moreover, showed to inhibit early steps of the replication cycle.
Significance and Impact of the Study: CHLN demonstrated promising selectivity index for both virus strains; therefore, it can be used for the development of an antiviral agent. 相似文献
Methods and Results: Virucidal activity of CHLN was evaluated and the time-of-addition assay was performed as follows: before the infection (−1 and −2 h), at the time of the infection (0 h) and after the infection (1 and 2 h). Plaque reduction assay (PRA) showed that CHLN inhibited BoHV-1 and PV-1 infection and the 50% inhibitory concentrations (IC
Conclusions: These results demonstrated that CHLN could be used as an antiviral suggesting directed activity on virus particles and on virus-receptor sites to BoHV. For poliovirus, CHLN also demonstrated virucide activity, moreover, showed to inhibit early steps of the replication cycle.
Significance and Impact of the Study: CHLN demonstrated promising selectivity index for both virus strains; therefore, it can be used for the development of an antiviral agent. 相似文献
527.
528.
B Bottazzi A Rambaldi M Introna A Merendino F Piovella R Bassan P Viero T Barbui A Mantovani 《Natural immunity and cell growth regulation》1986,5(1):19-27
We have investigated 10 patients with T gamma-lymphoproliferative disorders (T gamma LPD) for cell migratory capacity. Large granular lymphocytes (LGLs) expanding in these subjects expressed natural killer cell markers (HNKI, B73.1, AB8.28, N901, OKM1) to a variable extent. The patients' LGLs mediated antibody-dependent cellular cytotoxicity, while appreciable natural killer activity was only measurable in 3 patients. The migratory capacity of T gamma LPD was examined by using nitrocellulose filters. The patients' LGLs migrated into filters and showed responsiveness (in 9 of 10 patients) to activated serum, used as chemoattractant, as normal LGLs do. No clearcut correlation emerged between in vitro migratory capacity and disease aggressiveness or involvement of abdominal organs. These results confirm in T gamma LPD the migratory potential of LGLs and suggest the possibility that acquisition of enhanced locomotor capacity is not a crucial determinant of disease aggressiveness in T gamma LPD. 相似文献
529.
Anti-hyaluronidase activity of some pyrazole derivatives 总被引:1,自引:0,他引:1
530.