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21.
A. Sabbah  S. Hassoun  J. Le  Sellin  C. Andre  H. Sicard 《Allergy》1994,49(5):309-313
Fifty-eight patients with well-documented history of seasonal rhinoconjunctivitis caused by grass pollens were allocated randomly on a double-blind basis to receive either sublingual therapy with a solution of purified, standardized allergen preparation (Stallergenes) or a matched placebo for 17 weeks. The assessment of the effect of oral immunotherapy, done with drops of five-grass allergen extract, was on the clinical symptoms and on the medication score of the authorized rescue treatments. The actively treated patients had significantly (P<0.05 to P<0.01) fewer symptoms of rhinitis (sneezing and rhinorrhea) and of conjunctivitis (redness and tears) during the pollen season than the placebo group. Consumption of nasal solution of sodium cromoglycate and of betamethasone and dexchlorpheniramine was significantly less in the desensitized group (P<0.01). Side-effects were negligible. This study concludes that perlingual immunotherapy with grass pollen extract in grass-pollen-sensitive seasonal hay fever and conjunctivitis patients is effective, easy to perform, inexpensive, and safe.  相似文献   
22.
Nano-C60 cytotoxicity is due to lipid peroxidation   总被引:20,自引:0,他引:20  
This study examines the biological effects of water-soluble fullerene aggregates in an effort to evaluate the fundamental mechanisms that contribute to the cytotoxicity of a classic engineered nanomaterial. For this work we used a water-soluble fullerene species, nano-C60, a fullerene aggregate that readily forms when pristine C60 is added to water. Nano-C60 was cytotoxic to human dermal fibroblasts, human liver carcinoma cells (HepG2), and neuronal human astrocytes at doses 50 ppb (LC50=2–50 ppb, depending on cell type) after 48 h exposure. This water-soluble nano-C60 colloidal suspension disrupts normal cellular function through lipid peroxidation; reactive oxygen species are responsible for the membrane damage. Cellular viability was determined through live/dead staining and LDH release. DNA concentration and mitochondrial activity were not affected by the nano-C60 inoculations to cells in culture. The integrity of cellular membrane was examined by monitoring the peroxy-radicals on the lipid bilayer. Subsequently, glutathione production was measured to assess the cell's reaction to membrane oxidation. The damage to cell membranes was observed both with chemical assays, and confirmed physically by visualizing membrane permeability with high molecular weight dyes. With the addition of an antioxidant, l-ascorbic acid, the oxidative damage and resultant toxicity of nano-C60 was completely prevented.  相似文献   
23.
Radiation exposure is an occupational hazard for military personnel, some health care professionals, airport security screeners, and medical patients, with some individuals at risk for acute, high-dose exposures. Therefore, the biological effects of radiation, especially the potential for chromosome damage, are major occupational and health concerns. However, the biophysical mechanisms of chromosome instability subsequent to radiation-induced DNA damage are poorly understood. It is clear that interphase chromosomes occupy discrete structural and functional subnuclear domains, termed chromosome territories (CT), which may be organized into ‘neighborhoods’ comprising groups of specific CTs. We directly evaluated the relationship between chromosome positioning, neighborhood composition, and translocation partner choice in primary lymphocytes, using a cell-based system in which we could induce multiple, concentrated DNA breaks via high-dose irradiation. We critically evaluated mis-rejoining profiles and tested whether breaks occurring nearby were more likely to fuse than breaks occurring at a distance. We show that CT neighborhoods comprise heterologous chromosomes, within which inter-CT distances directly relate to translocation partner choice. These findings demonstrate that interphase chromosome arrangement is a principal factor in genomic instability outcomes in primary lymphocytes, providing a structural context for understanding the biological effects of radiation exposure, and the molecular etiology of tumor-specific translocation patterns.  相似文献   
24.
Characterization of FMR1 proteins isolated from different tissues   总被引:1,自引:5,他引:1  
FMR1 protein expression was studied in different tissues. Inhuman, monkey and murine tissues, high molecular mass FMR1 proteins(67–80 kDa) are found, as shown in lymphobiastoid celiiines. The identity of these proteins was confirmed by theirabsence in tissues from patients with the fragile X syndromeand a FMR1 knock-out mouse. An IIe367Asn substitution in theFMR1 protein did not aiter the transiation, processing and localizationof FMR1 proteins in lymphoblastoid cells from a patient carryingthis mutation. All the high molecular mass FMR1 proteins isolatedfrom normal lymphoblastoid cells and cells from the patientwith the IIe367Asn substitution were able to bind RNA. However,the FMR1 proteins of the patient had reduced affinity for RNAbinding at high salt concentrations. In some human, monkey andmurine tissues low molecular mass FMR1 proteins (39–41kDa) were found, which had the same N terminus as the 67–90kDa isoforms, but differ in their C terminus and are thereforemost likely the result of carboxy-terminal proteolytic cleavage.These low molecular mass FMR1 proteins did not bind RNA, incontrast with the high molecular mass FMR1 proteins. The significanceof these low molecular mass proteins remains to be studied.  相似文献   
25.
Psychological test scores of 13 identical and six fraternal pairs of twins aged 77–88 years were analyzed. These individuals are the survivors of a group of senescent twins studied earlier. The identical twins remained more similar than the fraternal ones, and there was a remarkable conservation of cognitive abilities in most individuals. Moreover, preservation of intelligence and longevity may be related.  相似文献   
26.
Prior electrical stimulation of the medial prefrontal cortex MFC facilitated the subsequent acquisition of intracranial self-stimulation (ICSS) from the same MFC electrode site. Stimulations that were spaced over a period of six days were more effective in producing this facilitation than the same number of stimulations delivered over a two day period. These data suggest that the rewarding effects of MFC stimulation may involve some process akin to the kindling phenomenon and as such may provide insights in the neuronal modifications thought to underlie learning and memory.  相似文献   
27.
The histochemical binding pattern of the peanut (Arachis hypogaea) lectin (PNA) was quantitatively described by means of computer-assisted microscope analysis in 28 benign prostatic hyperplasias (BPH), 15 prostatic intraepithelial neoplasias (PIN), and 119 prostatic adenocarcinomas. PNA exhibits noninunune but selective binding to glycoproteins with β-D-galactosyl(1,3)-N-acetyl-D-galactosamine residues. We also investigated whether a relationship existed between the number of histochemical-related PNA acceptors and the histochemical prostate-specific antigen (PSA) stain intensity, and between the number of PNA receptors and DNA ploidy level. The results show that neoplastic prostate tissues and high-grade intraepithelial prostatic neoplasias (PIN2_3) exhibit a significantly higher number of PNA acceptors than benign prostatic hyperplasias and low (PIN1) grade prostatic intraepithelial neoplasias. A statistically significant correlation was observed between the number of histochemically related PNA acceptors and PSA immunostain intensity. Lastly, diploid prostatic tumors, whether benign or malignant, exhibited a significantly higher number of PNA acceptors than aneuploid ones. These results suggest that PNA acceptors play an important role in the biology of prostate tumors.  相似文献   
28.
The question whether salpingectomy has a negative influenceon ovarian function and the outcome of pregnancy in an in-vitrofertilization (IVF) and embryo transfer treatment programmeis not yet answered. We performed a retrospective case-controlstudy to investigate the possible negative effect of salpingectomyon ovarian response to human menopausal gonadotrophins (HMG)during IVF and embryo transfer. The study group was composedof 26 patients with bilateral salpingectomy. In 67 cycles weanalysed different parameters of ovulation such as the numberof days of ovarian stimulation, numbers of ampoules of HMG,pre-ovulatory oestradiol concentrations and the numbers of oocytesretrieved. These parameters were compared to a control groupof 134 cycles in 134 women with healthy Fallopian tubes. Nodifferences were found. Implantation ratio, pregnancy rate andoutcome were the same in both groups. We conclude that bilateralsalpingectomy had no detrimental effect on ovarian performanceduring IVF and embryo transfer treatment nor on the outcome.  相似文献   
29.
By functional complementation of a PDR5 null mutant of Saccharomyces cervisiae, we have cloned and sequenced the multidrug-resistance gene CDR1 of Candida albicans. Transformation by CDR1 of a PDR5-disrupted host hypersensitive to cycloheximide and chloramphenicol resulted in resistance to cycloheximide, chloramphenicol and other drugs, such as the antifungal miconazole, with collateral hypersensitivity to oligomycin, nystatin and 2,4 dinitrophenol. Our results also demonstrate the presence of several PDR5 complementing genes in C. albicans, displaying multidrug-resistance patterns different from PDR5 and CDR1. The nucleotide sequence of CDR1 revealed that, like PDR5, it encodes a putative membrane pump belonging to the ABC (ATP-binding cassette) superfamily. CDR1 encodes a 1501-residue protein of 169.9 kDa whose predicted structural organization is characterized by two homologous halves, each comprising a hydrophobic region with a set of six transmembrane stretches, preceded by a hydrophilic nucleotide binding fold.  相似文献   
30.
The synthesis and second harmonic coeficients d33, d 31 and the susceptibilities χ(2) are reported of three series of (co)polymethacrylates that possess 4-(2,2-dicyanovinyl)- or 4-(2-cyano-2-methoxycarbonyl)vinyl-N,N-dialkylaniline (P1 and P2), 4-(2,2-dicyanovinyl)- or 4-(2-cyano-2-methoxycarbonyl)vinyl-(-piperidino)benzene (P5 and P6) and 4-(2,2-dicyano)- or 4-(2-cyano-2-methoxycarbonyl)vinyl-1-alkoxybenzene (P3 and P4) dyes
  • 1 System. names of the monomers see Exptl. part.
  • . The second-order nonlinear optical properties of corona-poled aligned polymer films were evaluated by second harmonic generation measurements. The χ values for the P1 and P2 polymers vary from 58 to 318, respectively 32 to 106 · 10?9 esu, for P3 and P4 from 7,6 to 19, respectively 4,4 to 7,4 · 10 ?9 esu and for P5 and P6 from 219 to 42,8 respectively 28,1 to 8,1 · 10?9 esu, depending on the dye chromophore concentration incorporated in the polymer structure.  相似文献   
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