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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
2.
L R Chaudhary 《Biochimica et biophysica acta》1976,424(3):489-492
Both phospholipases A1 and A2 activities (EC 3.1.1.4) at pH 7.4 were found to be significantly decreased in retinol-deficient rat testes supplemented with retinoic acid as compared to retinol-fed controls using 1-acyl-2-[1-(14)C]-oleoyl-sn-glycero-3-phosphocholine as substrate. However, little or no difference was observed in phospholipase A1 activity at pH 3.0 in both groups of rats. 相似文献
3.
Schizomeris leibleinii Kütz was collected from Dehra Dun as well as from Varanasi and the observations on its morphology, asexual reproduction and cytology were made by using material from nature and in culture. Cultural studies have revealed some interesting features such as occasional branching of uniseriate as well as multiseriate filaments and extensive development of the holdfast lobes into uniseriate or multiseriate filaments which may sometimes be branched. The chromosome number for the present alga has been determined to be 14, which differs from three earlier chromosome numbers reported for the same species by previous workers. Besides differing in chromosome number, it also differs significantly in its karyotype as compared with others. Thus this alga is considered to be a new chromosomal race of S. leibleinii. The present observations which have been discussed in the light of the recent work of Campbell & Sarafis (1972) who proposed a merger of Schizomeris with Stigeoclonium tenue, do not seem to favour such a merger. 相似文献
4.
The tolerance of a cell line (IMC-HZ-1) from a moth, Heliothis zea, for the monovalent cations Na+ and K+ were defined. Cells shifted to media containing more than 70 mM of K+ showed decreased growth rates. No evidence was obtained for Na+ toxicity. The osmotic pressure tolerances were influenced by the K+ concentration of the medium. The richer the medium was in K+, the narrower was the spectrum of osmotic pressure tolerance. Once the limit of K+ tolerance was exceeded, the rate of decline of growth was linear with respect to further increases in K+. This rate of decline was independent of osmotic pressure. The initial responses of cells during one subculture (2 to 4 population doublings) in media differing from the standard medium (used to maintain the cell line) were not reliable indicators of the growth potential of the cells. Continued subculture in such media resulted in an upward trend in population growth rates in most cases. 相似文献
5.
6.
Biological soil crusts in ecological restoration: emerging research and perspectives 总被引:1,自引:0,他引:1
Anita Antoninka Akasha Faist Emilio Rodriguez‐Caballero Kristina E. Young V. Bala Chaudhary Lea A. Condon David A. Pyke 《Restoration Ecology》2020,28(Z2):S3-S8
Drylands encompass over 40% of terrestrial ecosystems and face significant anthropogenic degradation causing a loss of ecosystem integrity, services, and deterioration of social‐ecological systems. To combat this degradation, some dryland restoration efforts have focused on the use of biological soil crusts (biocrusts): complex communities of cyanobacteria, algae, lichens, bryophytes, and other organisms living in association with the top millimeters of soil. Biocrusts are common in many ecosystems and especially drylands. They perform a suite of ecosystem functions: stabilizing soil surfaces to prevent erosion, contributing carbon through photosynthesis, fixing nitrogen, and mediating the hydrological cycle in drylands. Biocrusts have emerged as a potential tool in restoration; developing methods to implement effective biocrust restoration has the potential to return many ecosystem functions and services. Although culture‐based approaches have allowed researchers to learn about the biology, physiology, and cultivation of biocrusts, transferring this knowledge to field implementation has been more challenging. A large amount of research has amassed to improve our understanding of biocrust restoration, leaving us at an opportune time to learn from one another and to join approaches for maximum efficacy. The articles in this special issue improve the state of our current knowledge in biocrust restoration, highlighting efforts to effectively restore biocrusts through a variety of different ecosystems, across scales and utilizing a variety of lab and field methods. This collective work provides a useful resource for the scientific community as well as land managers. 相似文献
7.
R J Kreitman C B Siegall V K Chaudhary D J FitzGerald I Pastan 《Bioconjugate chemistry》1992,3(1):63-68
Pseudomonas exotoxin (PE) is a potent cytotoxic agent that is composed of 613 amino acids arranged into three major domains. We have previously identified two positions where ligands can successfully be placed in PE to direct it to cells with specific surface receptors. One site is at the amino terminus and the other is close to but not at the C-terminus. To examine the possibility of constructing oncotoxins with two different recognition elements that will bind to two different receptors, we have placed cDNAs encoding either transforming growth factor alpha (TGF alpha) or interleukin 6 (IL6) at the 5' end of a PE gene and also inserted a cDNA encoding TGF alpha near the 3' end of the PE gene. The plasmids encoding these chimeric toxins were expressed in Escherichia coli and the chimeric proteins purified to near homogeneity. In all the new toxins, the TGF alpha near the C-terminus was inserted after amino acid 607 of PE and followed by amino acids 604-613 so that the correct PE C-terminus (REDLK) was preserved. For each chimera, the toxin portion was either PE4E, in which the cell binding domain (domain Ia) is mutated, PE40, in which domain Ia is deleted, or PE38, in which domain Ia and part of domain Ib are deleted. These derivatives of PE do not bind to the PE receptor and allow 607, 355, or 339 amino acids, respectively, between the two ligands.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
8.
Showket Hussain Vilas Nasare Malasha Kumari Shashi Sharma Mohammad Aijaz Khan Bhudev C. Das Mausumi Bharadwaj 《PloS one》2014,9(11)
Background
Human Papillomavirus (HPV) -associated cervical cancer is the second-most common cancer in women worldwide but it is the most frequent gynaecological cancer and cancer associated death in India women. The objective of this study was to assess knowledge about cervical cancer, HPV, HPV vaccine, HPV vaccine acceptance among school and undergraduates students and their parent’s perception about acceptance of HPV vaccine in Northern part of India (Delhi and NCR regions).Materials and Methods
A qualitative questionnaire based survey among 2500 urban/rural students aged 12–22 years was conducted.Results
Overall, a low frequency (15%) of HPV and cervical cancer awareness was observed in students and their parents. However, the awareness was much higher in females belonging to urban setup compared to boys with a perception that HPV causes cervical cancer in women only. Additionally, only (13%) participants who were aware of cervical cancer and HPV) were willing to accept HPV vaccination. Apparently, parents of female students were two times more willing to accept HPV vaccination for their ward than male students (p<0.001; OR 95%CI = 2.09 (1.58–2.76).Conclusion
Cervical cancer and HPV awareness among school, undergraduate students and also to their parents was found to be very low in this part of India. The level of awareness and education appears to be insignificant determinants in rural compared to urban setup. Better health education will be needed to maximize public awareness for cervical cancer prevention. 相似文献9.
Karl Deacon David Onion Rajendra Kumari Susan A. Watson Alan J. Knox 《The Journal of biological chemistry》2012,287(47):39967-39981
10.