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61.
Preparation of highly active rabbit antisera (AS) to human recombinant alpha 2-interferon and their use for studying biological properties of natural and plasmid alpha-interferons are described. By exhaustion of AS by alpha 3-interferon there were prepared practically monospecific AS not reacting with antigenic determinants of alpha 3-interferon. It was found that alpha 3-interferon represented a significant portion of human lymphoblastoid interferons and was included in PH-labile alpha-interferon from serum of patients with Kaposi carcinoma. AS to alpha 2-interferon completely neutralized antiviral and antiproliferative activity of the homologous subtype alpha-interferon and stimulation of cytotoxicity of human natural killer cells induced by it. It neutralized also the same effects of the heterologous subtypes (alpha 3 and alpha F/D) and leukocytic interferon, but the neutralization level was lower. The results of the study confirmed the polyfunctional nature of the interferon molecule.  相似文献   
62.
Fragments of Drosophila melanogaster DNA that intensively hybridize with simple sequences poly[(dG-dT).(dC-dA)], poly[(dA).(dT)] and poly[(dG-dA).(dC-dT)] were cloned. The first two types of simple sequences are organized in these clones as separated stretches of moderate length, repeated many times within 12-15 kb. Each cluster contains only one type of the simple sequences and originates from a unique in the genome. In contrast, poly[(dG-dA).(dC-dT)] occurs in the genome as several isolated motifs.  相似文献   
63.
Ten strains of influenza A (H3N2) virus isolated from an outbreak in 1983, and ten strains isolated in 1985 from sporadic cases of infection were included in the study. For characterization of envelope antigens were used the polyclonal and monoclonal antibodies tested in the reaction of haemagglutinin inhibition, neuraminidase inhibition, and by lectin test. The strains but slightly different in the tests with polyclonal antibodies could clearly be classified to 3-4 groups using 5 monoclonal antibodies to H antigen of A/Bangkok 1/79 and A/Philippines 2/82 strains. Strains from the 1983 epidemics represent a more homogeneous group of which only one of ten strains failed to react with monoclonals of the strains A/Bangkok and A/Philippines. Strains from sporadic cases of infection in 1985, except for two strains, did not react at all with the monoclonal discriminating A/Bangkok and A/Philippines. The other strains could be classified to three groups, i.e. whether they agreed with 4, 2 or none of the A/Philippines H antigen epitopes. Alterations of neuraminidase are less apparent, and cannot be defined by means of normal immune sera. With the use of monoclonal antibodies the strains under study do not react any more with the strains of 1968-1973 influenza virus; yet the monoclonals to A/Texas/77 strain still do recognize one or two epitopes of the 1983-1985 strains.  相似文献   
64.
A. R. Slabas  C. G. Smith 《Planta》1988,175(2):145-152
Immunogold labelling was used to study the distribution of acyl carrier protein (ACP) in Escherichia coli and a variety of plant tissues. In E. coli, ACP is distributed throughout the cytoplasm, confirming the observation of S. Jackowski et al. (1985, J. Bacteriol., 162, 5–8_. In the mesocarp of Avocado (Persea americana) and maturing seeds of oil-seed rape (Brassica napus cv. Jet Neuf), over 95% of the ACP is localised to plastids. The protein is almost exclusively located in the chloroplasts of leaf material from oil-seed rape. Approximately 80% of the gold particles associated with the ACP were further localized to the thylakoid membrane of the chloroplast. Since acetyl-CoA carboxylase has been reported to be localized to the thylakoid membrane (C.G. Kannangara and C.J. Jensen, 1975, Eur. J. Biochem., 54, 25–30), these results are consistent with the view that the two sequential enzymes in fatty-acid synthesis are in close spacial proximity.Abbreviations ACC acetyl CoA carboxylase - ACP acyl carrier protein - FAS fatty-acid synthetase  相似文献   
65.
Summary Phenotypic analyses of genetic combinations involving the gene extramacrochaetae (emc) reveal its participation in the differentiation of both sensory elements and wing veins. The study of near-amorphic alleles of emc in mitotitc recombination clones indicates that it also affects cell proliferation. These clones show abnormal sizes, shapes and spatial distribution. They differentiate extra sensory elements as well as extra veins. A gain of function mutation in the gene causes opposite phenotypes in both differentiation systems. The effects of the mutant on proliferation and patterning are consistent with the emc gene being involved in the transfer of information between neighbouring cells, which leads to the spatial expression of the achaetescute gene complex and genes involved in vein formation.  相似文献   
66.
The article presents the review of modern data of the field and laboratory investigations of primate sexual behavior, cyclicity, reproductive strategies and copulation in different primates taxa: strepsirrhini, platyrrhyni, catarrhini. The specific character, progressiveness and adaptation of some reproductive models are discussed by the authors. A problem of connection between dominance and reproductive success is also discussed, the role of sexual teaching in postnatal ontogenesis, age and hormonal status for expression of sexual behavior are analysed. Some forms of sexual declinations in primates are considered.  相似文献   
67.
68.
Adherence to these principles will not guarantee success, but the testimony of many famous scientists supports the hypothesis that these guidelines can significantly (p less than .05, Wilcoxon unpaired X-test run at pH 5.6) increase your chances of achieving recognition, acquiring wealth, and ultimately being known as a successful scientist. At the very least, they should prevent you from falling too far outside the boundaries of "normal" science where you could easily be branded for life as a troublemaker or heretic.  相似文献   
69.
Alexandra Dane Dor-Ner ("Ali" to friends) was a photographer, writer, and a producer of programs on child development. In February 1989, at the age of 41, she was diagnosed with malignant brain cancer. During the following months she underwent brain surgery, radiation, and implant radiation. Throughout her treatment, she continued to work on a novel and write stores and literary criticism. A volunteer in hospitals before her illness, she now became very active in a support group of brain tumor patients and often served as a first resource and contact for others diagnosed with brain cancer. All was very accomplished; her award-winning photographs have been exhibited in the Smithsonian Institution in Washington, and her articles and pictures were published in books, periodicals, and newspapers around the world. A native of Boston, Ali lived for 17 years in Israel, where she joined a group of photographers documenting disappearing neighborhoods in Jerusalem. She was awarded first prize in the "Israel Through the Camera''s Eye" competition in 1977. She also taught English and photography in Israeli high schools. Ali traveled extensively on photographic assignments. Early in their 22-year marriage, she and her husband circumnavigated the globe on a freighter, producing a documentary film of the voyage. "Memoirs of an Amnesiac" was written while Ali was a student at the Warren Wilson College Writers'' Program in North Carolina; she intended to explore the compensatory aspects of her disease. In February 1991, within days of completing the piece, Ali had a third brain operation to remove a regrowth of cancerous tumor cells, as well as necrotic tissue. Two days later, she was again operated on to remove blood clots resulting from the previous surgery. For the next 12 weeks she fought to regain her ability to walk, talk, and write. In May, she underwent a fifth operation to relieve pressure in the brain. She was still in the hospital when she learned, to her great pleasure, that she would be awarded a master of fine arts degree from Warren Wilson College. She died on June 19, 1991.  相似文献   
70.
OBJECTIVE--To assess the quality of toilet facilities available for disabled people in a large provincial teaching hospital. DESIGN--Survey of toilet facilities for patients on the wards and in the outpatient department. SETTING--Teaching hospital in Leeds. RESULTS--Although the quality of toilet facilities varied, none met the standards recommended by the British Standards Institution. The worst facilities were found on a ward accommodating elderly patients, where the toilets were unsuitable for use by disabled people and bedside commodes had to be used instead. CONCLUSION--Toilet provision within a major hospital failed to meet standards required for disabled people. Admission to hospital may therefore result in loss of independence and dignity. If hospitals are to be centres of excellence, greater consideration must be given to the requirements of disabled people in the design of new wards, and current inadequate facilities should be upgraded.  相似文献   
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