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21.
In the present study, attempt was made to compare agar with gum karaya as gelling agent in micropropagation of rough lemon (Citrus jambhiri Lush.). Initially nodal segments were cultured on agar-gel MS medium containing benzyladenine (BA), kinetin (KN), zeatin (ZN) (1.0–2.5 mg L?1) and malt extract (200–1,200 mg L?1) to standardize the medium. Maximum shoot regeneration (66.66%) was observed with KN 2 mg L?1 with an average shoot length of 0.73 cm. Gum karaya and agar was then evaluated at different concentration and combinations in same medium. The shoot regeneration response on media gelled with 30 g L?1 gum karaya was 62.49% with an average shoot length of 0.80 cm. Regenerated shoots were rooted on MS medium gelled with agar and supplemented with different concentrations (0.5–2.5 mg L?1) of indole-3-acetic acid (IAA), naphthalene acetic acid (NAA), and indole-3-butyric acid (IBA). Maximum response (52.77 %) was observed with IBA 2.0 mg L?1 with an average number of 2.58 roots/shoot. A maximum of 53.47% cultures showed root regeneration with an average number of 2.91 roots/shoot in 30 g L?1 gum karaya-gel medium. Texture measurements revealed that firmness of gum karaya-gel medium was nowhere near to that of agar. However, in their capability of supporting growth and differentiation of explants they are equal to agar medium. Gum karaya forms less adhesive and gummy medium as compared to agar. This study indicates that gum karaya can be used as gelling agent in place of agar. 相似文献
22.
23.
Trans-endocytosis of CD80 and CD86: a molecular basis for the cell-extrinsic function of CTLA-4 总被引:1,自引:0,他引:1
Qureshi OS Zheng Y Nakamura K Attridge K Manzotti C Schmidt EM Baker J Jeffery LE Kaur S Briggs Z Hou TZ Futter CE Anderson G Walker LS Sansom DM 《Science (New York, N.Y.)》2011,332(6029):600-603
Cytotoxic T lymphocyte antigen 4 (CTLA-4) is an essential negative regulator of T cell immune responses whose mechanism of action is the subject of debate. CTLA-4 shares two ligands (CD80 and CD86) with a stimulatory receptor, CD28. Here, we show that CTLA-4 can capture its ligands from opposing cells by a process of trans-endocytosis. After removal, these costimulatory ligands are degraded inside CTLA-4-expressing cells, resulting in impaired costimulation via CD28. Acquisition of CD86 from antigen-presenting cells is stimulated by T cell receptor engagement and observed in vitro and in vivo. These data reveal a mechanism of immune regulation in which CTLA-4 acts as an effector molecule to inhibit CD28 costimulation by the cell-extrinsic depletion of ligands, accounting for many of the known features of the CD28-CTLA-4 system. 相似文献
24.
Toxicological effects and recovery of the corneal epithelium in Cyprinus carpio communis Linn. exposed to monocrotophos: an scanning electron microscope study 下载免费PDF全文
Ravneet Kaur Uppal Mohinder Singh Johal Madan Lal Sharma 《Veterinary ophthalmology》2015,18(3):214-220
This study was conducted based on the evidence of fish habitats in North India being affected by organophosphate pesticides draining from agricultural fields into bodies of water, especially during the rainy season. Various tissues of fish such as scales, gills ovaries, kidney, and liver have been studied from the toxicological point of view, but the toxicological effects of aquatic pollutants on fish cornea have not been investigated to date. We conducted comparative toxicological studies on the cornea of Cyprinus carpio communis using two sublethal (0.038 and 0.126 ppm) concentrations of monocrotophos pesticide for 30 days. Corneas from all the groups were evaluated by a scanning electron microscope. The fish exposed to the monocrotophos pesticide developed corneal necrosis due to the formation of crystalloid‐like structures, thinning and shrinkage of microridges on the corneal epithelium. After 30 days, fish from the monocrotophos‐treated tank were transferred to normal environmental conditions. After 60 days under natural condition, epithelial cells did not fully recover. In conclusion, exposure to monocrotophos induces irreversible changes in the cornea of C. carpio communis. As fish and mammalian visual systems share many similarities, the reported finding may offer useful insights for further toxicological and ophthalmological studies in humans. 相似文献
25.
Pankaj Sharma Inderjit Singh Asmita Sirari Gaurav Khosla Gurjeet Singh Navkiran Kaur Ludhar Sarvjeet Singh 《Plant Breeding》2019,138(6):741-747
Inheritance of fertility restorer gene in pigeonpea was studied using F2 and BC1F1 populations derived from cross AL103A × IC245273. It was found to be controlled by single dominant gene. Out of 228 SSR primer pairs, 33 primer pairs showed parental polymorphism, while four primers were found polymorphic in bulk segregant analysis (BSA). These four primers viz., CcM 1615, CcM 0710, CcM 0765 and CcM 1522 were used for genotyping of F2 population and were found to be placed at 3.1, 5.1, 28.1 and 45.8 cM, respectively. Two of them, CcM 1615 and CcM 0710, evinced clear and unambiguous bands for fertility restoration in F2 population. The Rf gene was mapped on linkage group 6 between the SSR markers CcM 1615 and CcM 0710 with the distances of 3.1 and 5.1 cM, respectively. The accuracy of the CcM 1615 was validated in 18 restorers and six maintainer lines. The marker CcM 1615 amplified in majority of male restorer lines with a selection accuracy of 91.66%. 相似文献
26.
Various enzymes of the tricarboxylic acid cycle (TCA) viz., aconitase (E.C. 4.2.1.3), isocitrate dehydrogenase (E.C. 1.1.1.42), succinate dehydrognease (E.C. 1.3.99.1), fumarate reductase (NADH: fumarate oxido-reductase), fumarase (E.C. 4.2.1.2) and maltate dehydrogenase (E.C. 1.1.1.37) were detected in adult Haemonchus contortus (Nematoda: Trichostrongylidae), in vitro. Low activities of aconitase and isocitrate dehydrogenase suggested that the TCA cycle has a minor function and the pathway of CO2 fixation is the major pathway in the energy metabolism of the parasite. In vitro incubation in Tyrode's solution had no significant effect on TCA cycle enzymes and the worm was able to maintain normal metabolism for 12 h.The effects of dl-tetramisole and rafoxanide on various enzymes of the TCA cycle were studied in adult H. contortus. At 50 μg ml?1 varying degrees of succinate dehydrogenase and fumarate reductase activities were observed. At the same concentration, the activities of other enzymes remained unaltered. 相似文献
27.
Zimmerman KL Wilcke JR Robertson JL Feldman BF Kaur T Rees LR Spackman KA 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2005,34(1):7-16
BACKGROUND: The Systematized Nomenclature of Medicine (SNOMED) is an established standard nomenclature for the expression of human and veterinary medical concepts. Nomenclature standards ease sharing of medical information, create common points of understanding, and improve data aggregation and analysis. OBJECTIVES: The objective of this study was to determine whether SNOMED adequately represented concepts relevant to veterinary clinical pathology. METHODS: Concepts were isolated from 3 different types of clinical pathology documents: 1) a textbook (Textbook), 2) the Results sections of industry pathology reports (Findings), and Discussion sections from industry pathology reports (Discussion). Concepts were matched (mapped) by 2 reviewers to semantically-equivalent SNOMED concepts. A quality score of 3 (good match), 2 (problem match), or 1 (no match) was recorded along with the SNOMED hierarchical location of each mapped concept. Results were analyzed using Cohen's Kappa statistic to assess reviewer agreement and chi-square tests to evaluate association between document type and quality score. RESULTS: The percentage of good matches was 48.3% for the Textbook, 45.4% for Findings, and 47.5% for Discussion documents, with no significant difference among documents. Of remaining concepts, 40% were partially expressed by SNOMED and 14% did not match. Mean reviewer agreement on quality score assignments was 76.8%. CONCLUSIONS: Although SNOMED representation of veterinary clinical pathology content was limited, missing and problem concepts were confined to a relatively small area of terminology. This limitation should be addressed in revisions of SNOMED to optimize SNOMED for veterinary clinical pathology applications. 相似文献
28.
Three abortigenic Indian isolates of equine herpesvirus-1 (EHV-1) (Tohana, Hisar and Bikaner), along with two exotic abortigenic
isolates (AB4 and V592) and another EHV-1 isolate (Jind) obtained from a case of perinatal foal mortality, were studied for
variability. For this purpose, PCR and restriction endonuclease (RE) digestion techniques were used simultaneously as a DNA
fingerprinting system. Nine different regions of EHV-1 virus were amplified by PCR using primer pairs specific for the regions
and the products obtained from these regions were subsequently subjected to various restriction endonucleases to further assess
the variability in the number of RE sites as well as in their positions. No difference was observed in all the four abortigenic
isolates in terms of the size of different PCR products amplified by all the nine primer pairs, except for primer pairs ‘E’
and ‘C’. PCR products obtained with primer pair E revealed that Tohana and Bikaner isolates were most similar while Hisar
isolate was like V592 isolate. However, the PCR product obtained from Jind isolate had a size between the PCR products of
Hisar and Tohan/Bikaner isolates. The primer pair ‘C’ used to amplify the region between 1151 to 3679 in ‘Gene 1,2,3’ clearly
differentiated the EHV-1 isolate obtained from a case of perinatal foal mortality from isolates obtained from abortion cases.
This primer pair needs to be exploited more extensively for use as a potential marker for differentiating the EHV-1 isolates,
mainly the abortion cases from perinatal foal mortality ones. Restriction endonuclease studies done with PCR product of all
the isolates with various primer pairs did not reveal any changes in the position or number of RE sites present in the products
amplified, indicating no variation in different RE sites within the amplified PCR products. However, this study clarified
that all the Indian isolates belonged to the IP group of EHV-1. 相似文献
29.
Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) is an exotic species native to the USA, damaging cotton and other plant families. The
feeding potential of different development stages of Cryptolaemus montrouzieri Mulsant, a biological control agent against mealybugs, was investigated on different development stages of P. solenopsis. Fourth instar grubs and adults of C. montrouzieri were the most voracious feeders on different instars of mealybug. The number of 1st instar nymphs of mealybug consumed by 1st, 2nd, 3rd and 4th instar larvae and adult beetles of C. montrouzieri was 15.56, 41.01, 125.38, 162.69 and 1613.81, respectively. The respective numbers of 2nd and 3rd instar nymphs of mealybug consumed were 11.15 and 1.80, 26.35 and 6.36, 73.66 and 13.32, 76.04 and 21.16, 787.95 and 114.66.
The corresponding figures for adult female mealybugs were 0.94, 3.23, 8.47, 12.71 and 73.40, respectively. The results indicate
that C. montrouzieri has the potential to be exploited as a biocontrol agent in North India; inoculative releases of 4th instar larvae and adults may provide instant control of P. solenopsis. Field experiments should be conducted to determine the efficiency of the ladybird on this mealybug. 相似文献
30.