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1.
Changes in the protein and steroid hormones of follicular fluid, aspirated from different follicles of sheep and human ovaries, have been measured and correlated with the size of the follicles. As the fluid contains a number of proteins, steroids have been measured directly and after ether extraction. The follicular fluid concentrations of progesterone and 17 beta-oestradiol measured directly in the fluid increased with the size of the follicles. The levels of free testosterone remained constant in all sizes of follicles, while those of bound hormone showed a 10- to 15-fold increase over the free testosterone concentrations in both the sheep and human follicular fluid. A decrease in the levels of bound testosterone in the fluid of large follicles (LFFL) coincided with the increase in bound 17 beta-oestradiol, suggesting the possible conversion of bound testosterone to oestrogen as the follicle attained maturity. The ratio of follicle-stimulating hormone (FSH) to luteinizing hormone (LH) varied in the fluid obtained from different size follicles, being 1:7 in small (SFFL), 1.3.5 in medium (MFFL) and 1:2.3 in large (LFFL) follicles of sheep ovaries. The LH content of follicular fluid of different size follicles appeared to be the same, with LFFL showing a minor increase over SFFL. In the human, the fluid from medium follicles contained very little LH compared to LFFL. These differences in the pattern of LH levels present in the fluid from different size follicles between human and sheep ovaries presumably reflect species variations in the entry of LH into the follicles. 相似文献
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Incidence of actinomycetes infection in women using intrauterine contraceptive devices 总被引:1,自引:0,他引:1
Pancervicovaginal smears taken from 350 women using an intrauterine contraceptive device (IUD) were screened for the presence of actinomycetes organisms. Of the 12 cases in which actinomycetes-like organisms were seen in Papanicolaou-stained smears, the presence of actinomycetes organisms was confirmed by immunofluorescence in 10 cases. The prevalence of actinomycetes infection was thus 2.8% (10 of 350 cases) in the IUD users. Eight (4.3%) of 173 symptomatic subjects had actinomycetes infections. Two of the positive cases were asymptomatic. Eight of the ten patients with confirmed actinomycetes infection were using the Cu T device while two were wearing the Lippes Loop IUD. Seven of the ten patients had been using an IUD for more than two years. The time of insertion of the IUD (postpuerperal, postmenstrual or after medical termination of pregnancy) did not show any correlation with the presence of actinomycetes infection. Actinomyces israelii was responsible for the infection in eight cases while Arachnia propionica was seen in two cases. The organisms could not be grown in culture. 相似文献
4.
Protoplasts isolated from etiolated hypocotyls of 6-day-old seedlings of Brassica juncea cv RLM 198 were cultured in a modified V47 medium containing 7% mannitol, 2% sucrose, 1.0 mg/l 2,4-D, 0.1 mg/l NAA and 0.4 mg/l BAP, at a density of 5×104 protoplasts per ml of medium. Cultures were incubated in the dark at 25+1°C. After 7 d of culture, cell colonies were diluted with 8p medium containing 5% mannitol and a similar hormone combination as described earlier. After 14 d, cell colonies were embedded in 8p medium containing agarose and 3.5% mannitol. Immediately upon gelling, liquid 8p medium was added to each Petri dish as an overlayer, and cultures were incubated in the light. After a total of 3 to 4 weeks in culture, microcalli were obtained. A modified MS medium with 2% sucrose, 1.0 mg/l 2,4-D and 0.1 mg/l kinetin solidified with 0.5% agarose was used for growing microcalli into callus lines. On MS medium containing 2% sucrose, 0.1 mg/l IAA, 2.0 mg/l zeatin riboside and 2.0 mg/l BAP, solidified with 0.5% agarose, about 35% of the calli regenerated multiple shoots. The time required from culture of protoplasts to multiple shoot regeneration was about 10 weeks. Regenerated shoots were rooted and plants were re-established in a growth chamber at high frequency.Abbreviations 2,4-D
2,4-dichlorophenoxyacetic acid
- IAA
Indole-3-acetic acid
- NAA
-naphthaleneacetic acid
- BAP
6-benzylaminopurine
- IBA
Indole-3-butyric acid 相似文献
5.
Efficient plant regeneration via somatic embryogenesis has been developed in chickpea cultivar C235. Leaf explants, on MS medium supplemented with 1.25 mg/l 2,4-D and 0.25 mg/l kinetin, yielded somatic embryos with high efficiency during dark incubation. MS medium supplemented with B5 vitamins, 0.125 mg/l IBA and 2 mg/l BAP was found suitable for embryo maturation. The well formed embryos germinated into plantlets on basal B5 medium supplemented with 0.25 mg/l BAP. Further development into healthy plantlets was obtained on basal B5 medium. Hardened plantlets produced normal, fertile plants upon transfer to soil.Abbreviations 2,4-D
2,4-dichlorophenoxyacetic acid
- BAP
6-Benzyl-aminopurine
- IAA
IndoIe-3-acetic acid
- IBA
Indole-3-butyric acid
- NAA
1-Naphthalene acetic acid
- Kinetin
6-furfuryl aminopurine
- Zeatin
6-(4-hydroxy-3-methylbut-2-enylamino)-purine 相似文献
6.
S. B. Narasimhulu P. B. Kirti S. R. Bhatt Shyam Prakash V. L. Chopra 《Plant cell reports》1994,13(11):657-660
Camelina sativa is a wild crucifer that is reported to be resistant to Alternaria blight. Polyethylene glycol mediated fusion was attempted between protoplasts from etiolated hypocotyls of Brassica carinata and mesophyll protoplasts of Camelina sativa. The mean frequency of heterokaryons was 6.8%. Three hybrid shoots were regenerated, each from a single fusionderived callus. These shoots failed to produce roots capable of withstanding transplantation. Confirmation of hybridity was obtained from the morphology of in vitro produced leaves, somatic chromosome number in leaf tips, and restriction fragment length polymorphism for a nuclear rDNA probe. Analysis for organelle constitution using RFLPs indicated that the hybrid contained chrloroplasts derived from the wild species and mitochondria from the cultivated Brassica species.Abbreviations 2,4-D
2,4-dichlorophenoxy-acetic acid
- IAA
Indole-3-acetic acid
- NAA
-Naphthaleneacetic acid
- IBA
Indole-3-butyric acid
- GA3
gibberellic acid
- BAP
6-Benzylaminopurine
- MS
Murashige and Skoog (1962) basal medium 相似文献
7.
8.
H. S. Vageeshbabu J. Venkateswari P. B. Kirti V. L. Chopra 《Journal of plant biochemistry and biotechnology.》1996,5(1):51-53
Metabolic engineering of the pathways of lipid biosynthesis has generated transgenic oilseed crops with enhanced levels of specialty fatty acids of Industrial value. Stearic acid, a 18:0 saturated fatty acid, is one such important fatty acid. Stearoylacyl carrier protein (stearoyl-ACP) desaturase (EC 1.14.99.6) catalyzes the first desaturation step in seed oil biosynthesis and converts stearoyl-ACP to oleoyl-ACP. We have cloned the complete coding region of the gene for this enzyme in Brassica juncea. Based on the sequence information of the gene in B. napus, 27-mer forward and reverse primers were designed each of which incorporated a Sal I restriciton site at the end. The primers were used to fish out the desaturase gene from B. juncea genome by polymerase chain reaction (PCR). The PCR product conformed to the average size of the coding region of the gene in B. napus. The PCR product was cloned in the pGem-T vector. The cloning was reconfirmed by restriction enzyme analysis and by PCR of the recombinant plasmid. The potential use of this gene in molecular farming of designer oilseed brassicas is discussed. 相似文献
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10.
The Natural Occurrence of Chickpea Chlorotic Dwarf Geminivirus in Chickpea and Faba Bean in the Sudan 总被引:1,自引:0,他引:1
A survey of faba bean and chickpea for virus infection, conducted during February 1994 in the Sudan, showed that bean yellow mosaic potyvirus and broad bean mottle bromovirus occurred commonly in both crops. Chickpea chlorotic dwarf geminivirus (CCDV) was detected for the first time in naturally infected chickpeas and faba beans. This is the first report of natural CCDV infection of chickpeas outside India and the first record of chickpea and faba bean infection in West Asia and North Africa (WANA). 相似文献