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11.
A J Smith M Mondain-Monval P Simon K Andersen Berg O P Clausen P O Hofmo R Scholler 《Journal of reproduction and fertility》1987,81(2):517-524
Bromocriptine administration in the form of slow-release injections to male blue foxes during March-May abolished the normal spring rise in plasma prolactin concentrations seen in May and June. The spring moult was prevented and the treated animals retained a winter coat of varied quality and maturity until the end of the study in August. Plasma testosterone concentrations fell normally from March until August. Testicular regression was, however, delayed, although there were individual variations in response. Estimation by DNA flow cytometry in early July of the relative numbers of haploid, diploid and tetraploid cells in the testis showed that, in the treated animals, 74-80% of the cells were haploid (maturing germinal cells), 4-6% tetraploid (mainly primary spermatocytes) and the rest diploid cells (somatic cells and the remaining germinal cell types). In the control males, however, no haploid cells were detected and the majority of cells were diploid (93-99%). At castration in August, histological examination revealed various stages of testicular regression in the treated and control animals. 相似文献
12.
Sabine Jell-Bahlsen 《Dialectical Anthropology》1988,13(2):199-207
Conclusion People have many names. But, changing one's name is no small thing. It can signify a major step in life or an embarrassing story, as in the last case.A person has a complex individual identity. His collective identity is clear from the moment he is conceived. He is one with a body of people, his kinsmen, who share one common ancestor and through him access to land and resources. The continuation of this group and its name is perpetuated through paternal descent.Kingroup membership ensures a person's place in life, his right to exist, eat, live and enjoy. But, who is he, apart from being a kinsman? Which kinsman is he? How are people going to interact with him? His individual identity will become clear through time. He is a re-incarnation of ancestor x. The circumstances of his birth were such. He behaves like this. He has these personal traits. This has happened to him. He has achieved that. There is no permanent role attached to an individual. He is neither bound to class nor caste. He is dynamic and changes constantly. His life is one of achievement, constant striving and upward mobility till death — when it all begins again. His name signals his state of being in time and existence.Sabine Jell-Bahlsen is an anthropologist and filmmaker. 相似文献
13.
Tina Pallesen Annette Vangsted Lars Drivsholm Henrik Clausen Jesper Zeuthen Håkan Wallin 《Glycoconjugate journal》1992,9(6):331-335
We here report an enzyme linked immunosorbent assay (ELISA) and a scintillation proximity assay (SPA) for detection of the ganglioside FucGM1 in sera from small cell lung cancer (SCLC) patients. The SPA was more sensitive and reproducible than the ELISA. In this assay, monoclonal antibodies specific for FucGM1 were bound to SPA particles and incubated with labelled FucGM1 and 100 µl test-serum overnight, and counted in a -counter. The sensitivity was 0.2 ng. Seven out of twenty sera from SCLC patients were positive, whereas none of twenty sera from healthy individuals were positive for FucGM1. The SPA was more sensitive than the previously reported HPTLC as well as a direct ELISA.Abbreviations MAb
monoclonal antibody
- SPA
scintillation proximity assay
- HPTLC
high performance thin layer chromatography
- SCLC
small cell lung cancer
- FucGM1
Fuc1-2Gal1-3GalNAc1-4(NeuAc2-3)-Gal1-4Glc1-1Cer
- ELISA
enzyme linked immunosorbent assay
- FCS
foetal calf serum
- PBS
phosphate buffered saline 相似文献
14.
Embryogenic suspension cultures of Abies alba were established using an embryogenic suspensor mass culture originating from the zygotic embryo in immature seed explants (Schuller et al. 1989). Protoplasts were isolated from the suspension material. The protoplasts were immobilized in alginate layers in order to follow the development of single protoplasts. During the first days of protoplast culture a modified Kao and Michayluk (1975) medium proved to be necessary for subsequent divisions. The formation of proembryos succeeded within 2–3 weeks when subcultured with a modified Schenk and Hildebrandt (1972) liquid medium. Light, enhanced sugar concentration, and the addition of abscisic acid led to the formation of slightly green torpedo-shaped somatic embryos after 6–8 weeks from protoplast isolation.Abbreviations ABA
abscisic acid
- BAP
N6-benzyladenine
- 2,4-D
2,4-dichlorophenoxyacetic acid
- ESM
Embryonal suspensor mass (Gupta and Durzan 1986)
- KM
Kao and Michayluk (1975)
- LP
(von Arnold and Eriksson 1977)
- MES
2-(N-morpholino)ethane-sulfonic acid
- NAA
1-naphthalene-acetic acid (sodium salt)
- PVP
polyvinylpyrrolidone
- SH
Schenk and Hildebrandt (1972)
- Tween 80
polyoxyethylene-sorbitan-monooleate 相似文献
15.
A unifying approach described by a random birth and death process which includes both environmental and demographic noise is introduced. It is shown that both of these noise sources play an essential role in extinction processes in general. The probability distribution of the lifetime of a population is determined and its dependence on the parameters of the model is discussed. Finally a population divided into subpopulations is modeled. The lifetime of this ensemble of subpopulations is compared to the lifetime of one large population. 相似文献
16.
Oliver Selberg Sabine Schlaak Hans J. Balks Alexander von zur Mühlen Manfred J. Müller 《European journal of applied physiology and occupational physiology》1991,63(6):417-423
The contribution of insulin (3.6 pmol.kg body mass-1.min-1) to adrenaline-induced (0.164 nmol.kg fat free mass-1.min-1) thermogenesis was studied in ten postabsorptive healthy volunteers using two sequential protocols. Variables considered were oxygen consumption as well as carbon dioxide production, heart rate, blood pressure, plasma concentrations of glucose, insulin, glycerol, free fatty acids, beta-HO-butyrate and lactate. Adrenaline increased plasma concentrations of glucose, glycerol, free fatty acids, and beta-HO-butyrate, and heart rate and metabolic rate during normo-insulinaemia [61.3 (SEM 6.6) pmol.l-1]. Similar effects were observed during hyperinsulinaemia [167.9 (SEM 18.7) pmol.l-1], but the effect of adrenaline on oxygen consumption was reduced. On average, metabolic rate increased by 12.9% during normo-insulinaemia and by 8.9% during hyperinsulinaemia. We concluded that relative hyperinsulinaemia resulted in decreased adrenaline-induced thermogenesis and therefore increased whole body anabolism. 相似文献
17.
Katrin Kausch Clemens R. Müller Tiemo Grimm Kenneth Ricker Marcella Rietschel Sabine Rudnik-Schöneborn Klaus Zerres 《Human genetics》1991,86(3):317-318
Summary Two recent articles have reported the linkage of a gene for recessive spinal muscular atrophy (SMA) on the chromosome region 5q11.2–13.3. Our data show no linkage of the dominantly inherited forms of SMA to this chromosome region. 相似文献
18.
S Hirohashi H Clausen E Nudelman H Inoue Y Shimosato S Hakomori 《Journal of immunology (Baltimore, Md. : 1950)》1986,136(11):4163-4168
A fusion of human lymphocytes released from regional lymph nodes of papillary adenocarcinoma of lung cancer with mouse myeloma P3-X63-Ag8-U1 cells resulted in a stable hybridoma-secreting human IgM antibody (NCC-1004) that reacts with a large proportion of squamous cell carcinomas of lung and esophagus as well as carcinoma of thyroid glands. However, the antibody also reacts with normal red blood cells, B lymphocytes, and a few other limited loci in normal tissues such as the basal cells of bronchial epithelium and the basal cell layer of stratified squamous epithelium, as well as endothelium and alveolar lining epithelium. The antigen defined by NCC-1004 has been characterized as blood group i antigen on the basis of the following results. The antibody preferentially agglutinates cord erythrocytes in contrast to adult erythrocytes. The agglutination was obvious at 4 degrees C, but diminished greatly at 37 degrees C, and was enhanced after sialidase treatment. The antibody specifically reacts with lacto-norhexaosylceramide (nLc6) and sialosyllacto-norhexaosylceramide (IV3NeuAcnLc6), but does not react with lacto-neotetraosylceramide (nLc4), sialosyllacto-neotetraosylceramide (IV3NeuAcnLc4), lacto-isooctaosylceramide (IV6Gal beta 1----4GlcNAcnLc6; I antigen), and other standard glycolipids so far tested. The properties of the antibody and its antigen are identical to those previously described for the i blood group system. Inasmuch as the hybridoma was established by hybridization of lymphocytes derived from regional lymph nodes of lung cancer, and the antigen was found in the patient's lung cancer tissue, the i antigen in lung cancer is probably recognized as a tumor-associated antigen by the host's immune cell system. 相似文献
19.
Daniel Chappard Christian Alexandre Sabine Palle George Riffat 《Biotechnic & histochemistry》1986,61(2):93-96
Polyester fibers are not dissolved by either glycol methacrylate or methyl methacrylate. Commercial polyester wadding is consequently an advantageous material to use in getting precise orientation of tissue specimens during embedding in methacrylate. 相似文献
20.
Altered growth kinetics precede calcium-induced differentiation in mouse epidermal cells 总被引:1,自引:0,他引:1
K. Elgjo H. Hennings O. P. F. Clausen 《In vitro cellular & developmental biology. Plant》1986,22(6):332-336
Summary Primary cultures of newborn mouse epidermal cells proliferate rapidly and with a high growth fraction for several months when
grown in medium with low calcium (0.02 to 0.1 mM). Addition of calcium to levels generally used in culture medium (1.2 mM) was followed by rapid changes in the pattern of proliferation. By using a combination of technics (a stathmokinetic method,
autoradiography, [3H]thymidine incorporation into DNA, DNA flow cytometry) it was found that cell flux was blocked for 5 to 6 h, followed by
a short rise in the mitotic rate at 10 h, and a gradual fall in all growth parameters until about 32 h after the calcium switch.
There was no accumulation of cells in any particular cell cycle phase. The results indicate that the calcium switch is followed
by a strong reduction in cell flux from G1 whereas the majority of the cells that had left G1 at the time of the switch completed one cell division before cessation of all proliferative activity. Both before and after
the switch the primary epidermal cultures consisted of one diploid and one tetraploid G1 DNA stemline that seemed to react in the same way to calcium.
This work reported in this paper was undertaken during the tenure of an American Cancer Society-Eleanor Roosevelt-International
Cancer Fellowship awarded by the International Union Against Cancer (K. E.). The project was supported by funds partly provided
by the International Cancer Research Data Bank Program of the National Cancer Institute, National Institutes of Health, Bethesda,
MD, under contract N01-C0-65341 (International Cancer Research Technology Transfer) and partly by the International Union
Against Cancer (O.P.F.C.). 相似文献