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1.
2.
Human immunodeficiency virus neutralizing antibodies recognize several conserved domains on the envelope glycoproteins. 总被引:67,自引:42,他引:25 下载免费PDF全文
D D Ho M G Sarngadharan M S Hirsch R T Schooley T R Rota R C Kennedy T C Chanh V L Sato 《Journal of virology》1987,61(6):2024-2028
Serum neutralizing antibodies against the human immunodeficiency virus were frequently detected in infected individuals, and low or absent serum neutralizing titers correlated with poor prognosis. Multiple diverse human immunodeficiency virus isolates were found to exhibit similar susceptibility to neutralization by a panel of human seropositive sera, suggesting that neutralizing antibodies are largely directed against conserved viral domains. Furthermore, utilizing antisera raised against a library of synthetic env peptides, four regions which are important in the neutralization process have been identified within both human immunodeficiency virus envelope glycoproteins (gp41 and gp120). Three of these are in conserved domains and should be considered for inclusion in a candidate vaccine. 相似文献
3.
Chromosome abnormalities in tuberous sclerosis 总被引:1,自引:1,他引:0
Susi Scappaticci D. Cerimele M. Tondi Rossella Vivarelli A. Fois M. Fraccaro 《Human genetics》1988,79(2):151-156
Summary In fibroblasts cultured from biopsies of the skin lesions of six patients with tuberous sclerosis (TS) there was a variable but consistent degree of karyotypic variation. Premature centromere disjunction (PCD) of all or part of the chromosomes, micronuclei, an increased incidence of breaks, dicentric chromosomes and the presence of polyploid metaphases were found in all cultures. The PCD was of the type encountered in Roberts syndrome and its frequency varied from 8% to 30%. In metaphases with PCD of one and of two chromosomes, the chromosome involved were identified, and chromosome 3 was involved 21 times among 59 chromosomes with PCD. Chromosome 3 tends to be preferentially involved in dicentric formation. In lymphocyte cultures from the same patients there were no metaphases with PCD, but there was a slight increase of breaks and the presence of dicentric chromosomes, also involving chromosome 3. Polyploid metaphases were increased in some of the cases. Karyotypic variation can be considered a cellular phenotypic characteristic of TS in fibroblasts cultured from the skin lesions, and its type indicates disturbances in the mechanics of centromere division and of chromosome distribution at cell division. 相似文献
4.
In maize leaves nitrogen (N)-deprivation induced a significant decline of chlorophyl and total N contents. On the contrary,
sulphur (S) content increased with N-deprivation. The activities of ATP-sulphurylase and O-acetylserine sulphydrylase also
decreased with N-deprivation, but ATP-sulphurylase activity was more sensitive than O-acetylserine sulphydrylase activity
to N-deficiency both in whole leaf extracts and in isolated leaf cells. Finally, N-deprivation induced higher changes in activity
of the two enzymes in mesophyll protoplasts than in bundle sheath strands.
This research was supported by Consiglio Nazionale delle Ricerche-Special grant I.P.R.A.-Subproject 1. Paper N. 73. 相似文献
5.
6.
Three species,Torodrilus gelidus sp. nov. (subfamily Rhyacodrilinae),Rossidrilus terraenovae gen. et sp. nov. (Limnodriloidinae), and a second unnamed species of Limnodriloidinae, are reported from marine sediments in Terra Nova Bay, Ross Sea. Torodrilus gelidus is distinguished fromT. lowryi Cook, 1970 by its setal pattern (with few exceptions, both anterior and posterior setae are single-pointed in sexually mature specimens ofT. gelidus) and the morphology of its male protuberances (the latter folded over a midventral bursa in segment XI).Rossidrilus terraenovae is characterized by large diverticula attached to the oesophagus in the posterior part of segment IX, unpaired male and spermathecal pores, heavily muscular and entally ciliated atrial ampullae, elongate prostatic pads, and a deep, unpaired and muscular, copulatory sac. It is the first species of its subfamily to be described from Antarctic waters. 相似文献
7.
Rossella Serra Gloria Isani Otello Cattani Emilio Carpené 《Biological trace element research》1996,51(1):107-116
Gilthead were fed three diets. Diet A was the control diet, whereas diets B and C were supplemented with 300 and 900 mg Zn/kg,
respectively. Fish fed with diet C, at the end of the experiment, showed the lowest weight. Zinc concentrations presented
the higher values in gills, liver, and kidney. Muscle and brain had the lower mean values and showed a tight control of zinc
levels. These results reinforce the hypothesis that zinc in the CNS should be strictly controlled in order to maintain the
functional role of the metal. Significant differences in tissue zinc concentrations were obtained between fish fed different
amounts of zinc, the metal concentrations being higher in tissues of fish fed diet C. The tissue decrease of zinc, found at
the end of the experiment, may depend on a lower feed consumption or on different zinc requirements during the cold season.
These changes, even if not univocal among the three diets, may be associated with the life cycle of fish. Furthermore, copper
concentrations were little affected by the different concentrations of zinc in the three diets; liver and kidney presented
the highest concentrations; liver showed a significant decrease in copper content at the end of the experiment. We conclude
that: zinc concentrations of the diet may affect the gilthead weights and the tissual metal content; and zinc concentrations
in the diets, depending on the growth rate, may be varied depending on the season. 相似文献
8.
Teresa Rondon Rota 《In vitro cellular & developmental biology. Plant》1977,13(5):280-292
Summary Trachoma organisms of serotype B were grown serially in irradiated cells (McCoy, BHK-21, Microbiological Associates, and BHK-21,
Lister) and tested for infectivity in monolayers of five mammalian cell lines (BHK-21, CHO, HeLa S3, McCoy and OWMK) and two diploid strains (ST/BTL and WI-38). All cell types had low susceptibility to chlamydial infection
but the number of inclusions increased when the inoculum was centrifuged onto the monolayers, or when the cells were irradiated.
Infection was higher in non-irradiated CHO than in irradiated CHO in three out of a total of six experiments. Inclusion number
was increased 300 times in HeLa S3 and up to three times in the other cell types after treatment with diethylaminoethyl-dextran (DEAE-D). Serial passage of
Chlamydia trachomatis serotype B (strain Har-36) in CO60 McCoy and CO60 BHK-21 Lister resulted in partial adaptation of the strain to the host cell. The phenomenon of adaptation of serotype B to
McCoy compensated for the lower susceptibility of this cell revealed when McCoy cells were inoculated with trachoma elementary
bodies grown in BHK-21 Lister or in chick embryo yolk sac. Trachoma organisms of immunotypes A, B and C prepared in yolk sac
produced more inclusion-forming units per ml in CO60 BHK-21 Lister than in CO60 McCoy.
This research was supported by a grant from the National Eye Institute (EI-00812-08), and by the Arabian American Oil Company.
The paper is dedicated to the memory of Francis B. Gordon, who pioneered research methods for the cultivation of trachoma
and inclusion conjunctivitis (TRIC) agents in cell culture. Dr. Gordon patiently studied tables and photographs which accompany
this text when he visited our laboratory on the day prior to his sailing to England on the ill-fated voyage in which he and
Mrs. Gordon perished (October 1973). 相似文献
9.
Efficient direct chromosome analyses and enzyme determinations from chorionic villi samples in the first trimester of pregnancy 总被引:14,自引:0,他引:14
G. Simoni B. Brambati C. Danesino F. Rossella G. L. Terzoli M. Ferrari M. Fraccaro 《Human genetics》1983,63(4):349-357
Chorionic villi were obtained by an aspiration technique which proved to be the best of four alternative procedures. We report in detail the series of experiments which led to (1) successful, rapidly growing cell cultures practically free of maternal cell contamination (the use of hormone-supplemented Chang medium greatly increased the growth rate); (2) an efficient direct method to obtain high quality metaphases from the Langhans cells of the cytotrophoblast tissue and with which the fetal karyotype is defined within a few hours of chorionic villi sampling; and (3) successful testing for the activity of eight enzymes directly from the villi samples, thus showing that this material is suitable for a rapid, direct diagnosis of the related metabolic diseases. 相似文献
10.