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41.
A series of histochemical procedures were employed to localize and characterize glycoprotein (GP) classes elaborated in the epithelia of the upper and lower lips and associated structures, namely the rostral cap, the adhesive pad, the horny upper and lower jaw sheaths and the folds of skin between them, of a hill stream fish Garra lamta. The epithelia of the lips, the folds of skin and the major portions of the rostral cap and the adhesive pad are mucogenic. The epithelia of the horny jaw sheaths and parts of the rostral cap and the adhesive pad are keratinized. Based on the histochemical characterization of GPs, the cells involved in the secretions in the epithelia at the mucogenic regions of the rostral cap and the adhesive pad comprise the epithelial cells, the type A mucous cells and the club cells. In the lips and the folds of skin, in contrast, the club cells are absent and most mucous cells belong to the type B category. Type A mucous cells are few. GPs elaborated by cellular components of the mucogenic epithelia include GPs with oxidizable vicinal diols, GPs with O-sulphate esters, GPs with sialic acid residues without O-acyl substitution or with O-acyl substitution at C7, C8 or C9 and GPs with O-acyl sugars. The different types of cells show significant differences in the classes as well as in the concentrations of the GPs elaborated by them. GPs have also been identified in the subcorneal space between the unculi and the epithelial cells in the replacement layer in the epithelia at the keratinized regions. Elaboration of more than one type of GPs suggests a basis for functional discrimination in their role in the mucous secretions at the surface as an adaptation to the feeding ecology and the environment inhabited by the fish.  相似文献   
42.
Tandon S  Mittal AK  Pant AK 《Fitoterapia》2008,79(4):283-286
Essential oils of Vitex trifolia and Vitex agnus-castus were evaluated against Vth instar larvae of Spilosoma obliqua, when applied topically on the dorsal side of mesothoracic region, for insect growth regulatory activity. This treatment caused extended larval period and pupal period, increase in larval mortality and adult deformity and decrease in adult emergence, fecundity of female and egg fertility of test insect.  相似文献   
43.
Carbonic anhydrase (CA) has been immobilized on chitosan stabilized iron nanoparticles (CSIN) for the biomimetic carbonation reaction. CSIN was characterized using scanning electron microscope, energy dispersive X-ray, X-ray diffraction spectroscopy, and Fourier transform infrared analysis. The effect of various parameters such as pH, temperature and storage stability, on immobilized CA was investigated using a p-NPA assay. Kinetic parameters of immobilized and free CA (K m and V max values) were also evaluated. The K m and V max for immobilized CA was 1.727?mM and 1.189???mol?min?1?ml?1, respectively, whereas for free enzyme the K m and V max was 1.594?mM and 1.307???mol?min?1?ml?1, respectively. It was observed that the immobilized enzyme had longer storage stability and retained 50?% of its initial activity upto 30?days at room temperature. CA immobilized on CSIN has been used for hydration of CO2, and the results were validated by using a gas chromatographic method. Proof of concept has been established for the biomimetic carbonation reaction. Immobilized CA show reasonably good CO2 sequestration capacity of 21.55?mg of CaCO3/mg of CA as compared to CO2 sequestration capacity of 34.92?mg of CaCO3/mg of CA for free CA respectively, under a limiting concentration of CO2 (14.5?mg of CO2/10?ml).  相似文献   
44.
45.
The Garole is a prolific breed of microsheep that possesses the FecB gene, which increases ovulation rate. The purpose of this study was to compare embryo production by multiple ovulation in seven Garole ewes with that in seven normal size, non-prolific Malpura ewes, and assess the influence of the large body size of Awassi crossbred recipient ewes on the birth-weight of Garole lambs. Oestrus was synchronised with two intramuscular injections of 7.5 mg prostaglandin F(2alpha) administered 10 days apart. The donor ewes were superovulated by the use of pregnant mare serum gonadotrophin and follicle-stimulating hormone. The onset and duration of oestrus were similar in both breeds. The Garole donors had higher total mean (se) ovarian responses (15.6 [3.6] v 9.1 [2.3]), ovulation rate (13.6 [3.1] v 8.4 [2.2]) and produced more transferable embryos (6.0 [3.5] v 4.0 [0.9]) than the Malpura donors, but the differences were not statistically significant. The Garole lambs produced by embryo transfer were on average 57.8 per cent heavier at birth than contemporary Garole lambs produced by natural mating.  相似文献   
46.
The composition and diversity of the bacterial communities associated with plant root is influenced by various biotic and abiotic factors. In this study, effect of soil management practices, conventional (pf) and raised bed (rb), are compared for bacterial diversity in rhizosphere of wheat (Triticum aestivum) var. UP2338, taking pseudomonads as a biomarker. Microbial diversity was assessed employing culturable and unculturable approaches. Amplified rDNA restriction analysis showed that soil management practices and site of sampling (rhizosphere-RS and rhizoplane-RP) affected the composition of microbial communities. Sample from conventional management showed a higher Pseudomonas diversity (H′ = 3.7) than that from raised bed (H′ = 2.78). However, total bacterial diversity (SSCP data) was more complex in rb than pf management. Dominant members of both pf and rb were γ-proteobacteria as Pseudomonas was dominant over other forms, while Bacillus species were only present as low numbers in rb.  相似文献   
47.
Summary Extent of heterosis for seed yield is an indicator for transgressive segregation in cross of self-pollinated crops. However, the extent of heterosis is thought to be related to the genetic diversity among the parents. Isoenzymic variation was used for estimating the genetic diversity. Eight varieties of green gram (Vigna radiata) were characterized for esterase, amylases, phosphatases, catalase and peroxidase isoenzymes. Differences in these systems were used to calculate a diversity index (D.I.). Hybrids produced from an inbred pair having higher D.I.'s outyielded those with low D.I.'s. However, the correlation (r) between D.I. and heterosis for seed yield was not consistent in different seasons but some of the desirable crosses could be singled out on the basis of D.I.  相似文献   
48.
Peanut plays a key role to the livelihood of millions in the world especially in Arid and Semi-Arid regions. Peanut with high oleic acid content aids to increase shelf-life of peanut oil as well as food products and extends major health benefits to the consumers. In peanut, ahFAD2 gene controls quantity of two major fatty acids viz, oleic and linoleic acids. These two fatty acids together with palmitic acid constitute 90% fat composition in peanut and regulate the quality of peanut oil. Here, two ahfad2 alleles from SunOleic 95R were introgressed into ICGV 05141 using marker-assisted selection. Marker-assisted breeding effectively increased oleic acid and oleic to linoleic acid ratio in recombinant lines up to 44% and 30%, respectively as compared to ICGV 05141. In addition to improved oil quality, the recombinant lines also had superiority in pod yield together with desired pod/seed attributes. Realizing the health benefits and ever increasing demand in domestic and international market, the high oleic peanut recombinant lines will certainly boost the economical benefits to the Indian farmers in addition to ensuring availability of high oleic peanuts to the traders and industry.  相似文献   
49.
Zinc was extracted from seven soils collected from Haryana state (India), representing the tropical region of the country, to predict the availability of Zn to crops. Weakly adsorbed Zn extracted by 0.05 M CaCl2 was almost negligible. Similarly 1 M MgCl2, designated to extract the lattice Zn, extracted small quantities of Zn indicating that no Zn was substituted for any other cation in clay lattice. Maximum zinc was extracted by chelating agents like DTPA and EDTA and were correlated significantly among themselves. None of the methods tested was significantly correlated to plant Zn indicating that in addition to crop requirement, other soil factors play a major role in determining the Zn availability. Equilibrium Zn values in all except a sandy soil, were less than 1 μg Zn/ml indicating the possibility of moderate to severe Zn deficiency in these soils.  相似文献   
50.
In the present study, the characterization of 3 atypical isolates of Actinobacillus pleuropneumoniae is presented. Two isolates (1B and 27E) showed positive reactions in coagglutination, immunodiffusion, and indirect hemagglutination tests for serotypes 1 and 7, whereas the third isolate (26B) reacted with antisera to serotypes 1, 4, and 7. These atypical isolates of A. pleuropneumoniae possessed a capsular polysaccharide (CPS) antigenically related to serotype 1 as well as an O-chain lipopolysaccharide antigenically related to serotype 7 or to serotypes 4 and 7, as shown by the use of monoclonal antibodies. Results of toxin profile and virulence assays for mice and pigs showed them to be more related to A. pleuropneumoniae serotype 7 field isolates. All 3 isolates induced antibodies mainly against serotype 7/4 O-long-chain lipopolysaccharide (LC-LPS) and, to a lesser extent, to the CPS of serotype 1, in experimentally infected pigs. Diagnostic laboratories that use a LC-LPS-based enzyme-linked immunosorbent assay (ELISA) for serodiagnosis of A. pleuropneumoniae infection in swine would probably diagnose herds infected with these atypical isolates as being infected by A. pleuropneumoniae serotypes 7 or 4, whereas those that use a CPS-based ELISA would probably consider them as infected by A. pleuropneumoniae serotype 1.  相似文献   
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