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1.
Previous studies using electroretinography and immunohistochemistry have shown normal cone function and structure in early stages of hereditary rod‐cone degeneration of Abyssinian cats. To further investigate the cone photoreceptors and the inner retina of dystrophic cats, antibodies against green‐ and blue‐sensitive cones and specific cell types of inner retina were used in seven cats with the recessively inherited rod‐cone degeneration, and three normal European short‐haired cats. There was a reduction in number of both types of cones early in the disease. Changes at early stages of disease also occurred among horizontal cells in which there was an extension and a thickening of their lateral processes. The regular configuration of bipolar cells was changed in the more advanced stages of disease and their apical dendrites were lost. Abnormalities were not observed in the amacrine cells and in the ganglion cell layer in any of the present cases. This study shows that the cone system is morphologically abnormal in young cats at an earlier stage of disease than previously shown. The present findings also support the assumption that the inner retina is largely preserved throughout the disease process.  相似文献   
2.
Forest fire in India: a review of the knowledge base   总被引:1,自引:0,他引:1  
Forest fire has profound impacts on atmospheric chemistry, biogeochemical cycling and ecosystem structure. This feedback interaction may be hastened in climate change scenarios. In view of this, the present day knowledge about the forest fire condition in India has been reviewed. Operational monitoring, geospatial modelling and climate change uncertainties are discussed. Indicators for forest fire assessment and the role of geoinformatics tools in developing those parameters are identified. The need for developing an adaptive management strategy from the existing experience is emphasized, and specific points are recommended sector-wise with short- and long-term visions.  相似文献   
3.
Drought indices (DI) are an useful tool for assessing different sectarian droughts. Standardized Precipitation Index (SPI) has been used worldwide to assess/monitor the onset, active phase, cessation and severity of drought. Normalized Difference Vegetation Index (NDVI) provides a comprehensive vegetation dynamics, which directly linked with rainfall received in a particular region. Indo-Gangetic Region (IGR), providing employment and livelihood to tens of millions of rural families directly or indirectly and rice (Oryza sativa L.)-wheat (Triticum aestivum L.) (RW) system of the Indo-Gangetic Plains (IGP) contributes 80% of the total cereal production and is critical to food security of the region. This study tries to verify the applicability of water-vegetative indices viz., SPI, Rainfall Index (RI) and NDVI for drought assessment of rice-wheat system productivity over IGR-India. The relationship between monsoon rainfall and NDVI shows that at around 1100 mm rainfall, the NDVI reached saturation point and no further significant increase in NDVI with increase of rainfall is noticed. Even though, there was a positive correlation of seasonal monsoon rainfall and average NDVI, conflicting results are noticed between monthly distribution of rainfall and monthly anomaly of NDVI over IGR States. It is noticed that June dif NDVI (actual NDVI-mean NDVI) contributes more to rice productivity followed by July. However, the combined effect of June, July and August, explains 15% of the variation of Kharif Rice Productivity Index (KRPI). As far as wheat is concerned, statistically significant relation was found between Wheat Productivity Index (WPI) and anomaly NDVI during December-March. This explains 35% of the variability in WPI.  相似文献   
4.
本研究以不同槟榔品种的幼嫩叶片及花序为外植体成功实现体细胞胚胎发生及植株再生.试验结果显示,不同品种及外植体均以毒莠定为最佳愈伤组织诱导剂.诱导所获愈伤组织需连续用生长素浓度由高到低的一系列培养基进行继代培养才能不断生长并诱导体细胞胚胎.当愈伤组织最终转移入无激素MS配养基后可观察到体细胞胚胎发生.胚胎萌发以附加20 ...  相似文献   
5.
Water mobility and distribution in cream cheeses with variations in fat (4, 15, and 26%), added salt (0, 0.625, and 1.25%), and pH (4.2, 4.7, and 5.2) were studied using (1)H NMR relaxometry. The cheese samples were inoculated with a mixture of Listeria innocua, Escherichia coli O157 and Staphylococcus aureus, and partial least-squares regression revealed that (1)H T(2) relaxation decay data were able to explain a large part of the variation in the survival of E. coli O157 (64-83%). However, the predictions of L. innocua and S. aureus survival were strongly dependent on the fat/water content of the samples. Consequently, the present results indicate that NMR relaxometry is a promising technique for predicting the survival of these bacteria; however, the characteristics of the sample matrix are substantial.  相似文献   
6.
Streptomyces griseus (MTCC 9723) is a chitinolytic bacterium isolated from prawn cultivated pond soil of Peddapuram Village; East Godavari District was studied in detailed. Chitinase (EC 3.2.1.14) was extracted from the culture filtrate of Streptomyces griseus and purified by ammonium sulfate precipitation, DEAE-cellulose ionexchange chromatography, Sephadex G-100 and Sephadex G-200 gel filtration chromatography. The molecular mass of the purified chitinase was estimated to be 34, 32 kDa by SDS gel electrophoresis and confirmed by activity staining with Calcofluor White M2R. Chitinase was optimally active at pH of 6.0 and at 40 degrees C. The enzyme was stable from pH 5-9 and up to 20-50 degrees C. The chitinase exhibited Km and Vmax values of 400 mg and 180 IU mL(-1) for colloidal chitin. Among the metals and inhibitors that were tested, the Hg+, Hg2+ and P-chloromercuribenzoic acid completely inhibited the chitinase activity at 1 mM concentration. The purified chitinase showed high activity on colloidal chitin, chitobiose, and chitooligosaccharide. An in vitro assay proved that the crude chitinase, actively growing cells of S. griseus having antifungal activity against all studied fungal pathogen. This result implies that characteristics of S. griseus producing endochitinase made them suitable for biotechnological purpose such as for degradation of chitin containing waste and it might be a promising biocontrol agent for plant pathogens.  相似文献   
7.
Testosterone (T) administration to maleAnabas testudineus significantly stimulated the activities of cytochrome oxidase, -glycerophosphate dehydrogenase (-GPDH) and Mg2+ adenosine triphosphatase (Mg2+ ATPase) and inhibited lactate dehydrogenase (LDH), cytosolic and mitochondrial malate dehydrogenases (MDH). The activities of succinate dehydrogenase (SDH), glucose-6-phosphate dehydrogenase (G-6-PDH) and catalase were unaffected by testosterone treatment. Administration of estradiol-17 (E2) in female fish, significantly stimulated cytochrome oxidase activity, inhibited Mg2+ ATPase, SDH, catalase and cytosolic and mitochondrial MDH activity, and was without effect on other enzymes studied.The simultaneous injections of actinomycin D or chloramphenicol and T or E2 prevented the hormonal influence on hepatic enzyme activities. The present study demonstrates that inA. testudineus sex steroids influence hepatic oxidative metabolism by a mechanism sensitive to the action of inhibitors of protein synthesis.  相似文献   
8.
The objectives of this research were to study the bioavailable calcium from widely used cereals and millets by an in vitro method and to provide data on the role of calcium inhibitors. The average total calcium content of the analyzed raw cereals and millets ranged from 10.2 to 324.6 mg/100 g (the lowest and highest values correspond to maize and finger millet, respectively), whereas the rest of the raw cereals and millets had calcium content in the range of 26.3–50.4 mg/100 g, except for rice samples (10.4 mg/100 g). Soluble percentage of calcium is the highest in maize (45.1%), and dialyzable calcium percentage is the highest in wheat (34.9%). The cooking process did not significantly affect calcium bioavailability and the contents of phytate and tannin. However, cooking reduced the oxalate content, and in the case of dietary fiber significant increase was observed. The order of oxalate content in the cereals and millets studied was found to be pearl millet > finger millet > wheat > maize > sorghum > rice. Multiple regression analysis carried out to explain the influence of oxalate, phytate, tannin, and dietary fiber on calcium bioavailability showed greater inhibitory effect of oxalate.  相似文献   
9.
Jatropha curcas L., an important biodiesel plant, has been studied for its distribution and diversity in south east coastal zone of India using DIVA-GIS. The Grid maps were generated on the distribution pattern, plant height, number of primary branches, collar length, number of fruits per cluster and oil content. Flowering in the collected accessions were grouped in to very early (35%), early (29%), medium duration (10%), late (20%), and very late (6%) types. Analysis for richness using rarefaction method of DIVA-GIS showed that Ranga Reddy district of Andhra Pradesh is the potential area for germplasm with high oil content. The present study revealed that diverse germplasm accessions of J. curcas are distributed all over the south east coastal zone and enabled us to find out gaps in collection and diversity richness from SEC zone of India for conservation.  相似文献   
10.
Normally, the data generated from farmer participatory trials (FPT) are highly unbalanced due to variation in the number of replicates of different treatments, the use of different varieties, farmers’ management of the trials, and their preferences for testing different treatments. The incomplete nature of the data makes mixed models the preferred class of models for the analysis. When assessing the relative performances of technologies, stability over a range of environments is an important attribute to consider. Most of the common models for stability may be fitted in a mixed-model framework where environments are a random factor and treatments are fixed. Data from on-farm trials conducted in the Indo-Gangetic Plain (IGP) of South Asia under the umbrella of Rice-Wheat Consortium (RWC) were analyzed for grain yield stability using different stability models. The objective was to compare improved resource management technologies with farmers’ practice. The variance components of an appropriate mixed model serve as measures of stability. Stability models were compared allowing for (i) heterogeneity of error variances and (ii) heterogeneity of variances between environments for farmers-within-environment effects. Mean comparisons of the treatments were made on the basis of the best fitting stability model. Reduced-till (non-puddled) transplanted rice (RT-TPR) and reduced-till drill-seeded wheat using a power tiller - operated seeder with integrated crop and resource management RTDSW(PTOS)ICRM ranked first in terms of both adjusted mean yield and stability.  相似文献   
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