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Uttam Kumar Sarkar Prashant Kumar Deepak Raje Singh Negi Shriprakash Singh Dhurendra Kapoor 《Biodiversity and Conservation》2006,15(11):3579-3589
Over the last few decades wild population of Chitala chitala (HamiltonBuchanan) has been declined more than 50% due to various reasons and is presently listed under endangered (EN) category
due to reduced abundance. In the present communication wild C. chitala were collected from natural habitats and induced to spawn under captivity during July 2002 by injecting three different doses
of synthetic hormone Ovaprim. Intramuscular injections were administered to fishes using three different doses (1.5, 1.0 and
0.5 ml/kg body weight). Artificial breeding pool was prepared for each set by encircling area (20 × 5 m) with mosquito net,
where wooden country boat (8 × 4 × 2.5 feet with surface area 48.5 sq. feet) was placed inside the breeding pool. Distinct
spawning behavior was noticed in the experimental sets with different hormonal dose whereas no spawning activity was noticed
in control set. The fertilization rate varied from 48.8680.2% and total numbers of spawned eggs in two sets of experiments
were estimated to be 81,034. The average number of eggs deposited 15 ± 2.1/square inches. The fertilized eggs were large in
size (4.5 ± 0.05 mm), adhesive and attached to the hard substratum. The eggs hatch out between 168192 h after fertilization
and about 33,639 hatchlings were produced. Newly hatched larvae measured 10.23 ± 0.03 mm and 0.031± 0.008 gm in weight and
the mean diameter of yolk sac was 4.1 ± 0.08 mm. The yolk sac remains attached up to a week. The percentage survival of hatchlings
varied from 42.2 to 65.60. Statistical analysis was worked out to determine the relation between the hormone dosage with different
breeding parameters like latency period, fertilization rate, egg output, hatching rate and hatchling production. 相似文献
103.
Carotenoid biosynthesis genes in rice: structural analysis, genome-wide expression profiling and phylogenetic analysis 总被引:1,自引:0,他引:1
Neetu Chaudhary Aashima Nijhawan Jitendra P. Khurana Paramjit Khurana 《Molecular genetics and genomics : MGG》2010,283(1):13-33
Carotenoids, important lipid-soluble antioxidants in photosynthetic tissues, are known to be completely absent in rice endosperm.
Many studies, involving transgenic manipulations of carotenoid biosynthesis genes, have been performed to get carotenoid-enriched
rice grain. Study of genes involved in their biosynthesis can provide further information regarding the abundance/absence
of carotenoids in different tissues. We have identified 16 and 34 carotenoid biosynthesis genes in rice and Populus genomes, respectively. A detailed analysis of the domain structure of carotenoid biosynthesis enzymes in rice, Populus and Arabidopsis has shown that highly conserved catalytic domains, along with other domains, are present in these proteins. Phylogenetic
analysis of rice genes with Arabidopsis and other characterized carotenoid biosynthesis genes has revealed that homologous genes exist in these plants, and the duplicated
gene copies probably adopt new functions. Expression of rice and Populus genes has been analyzed by full-length cDNA- and EST-based expression profiling. In rice, this analysis was complemented
by real-time PCR, microarray and signature-based expression profiling, which reveal that carotenoid biosynthesis genes are
highly expressed in light-grown tissues, have differential expression pattern during vegetative/reproductive development and
are responsive to stress. 相似文献
104.
Rajeev R. Raje Mingyong Qiao Snehasis Mukhopadhyay Mathew Palakal Shengquan Peng Javed Mostafa 《Cluster computing》2002,5(4):377-388
Recent advances in processor, networking and software technologies have made distributed computing a reality in today's world. Distributed systems offer many advantages, ranging from a higher performance to the effective utilization of physically dispersed resources. Many diverse application domains can benefit by exploiting principles of distributed computing. Information filtering is one such application domain. In this article, we present a design of a homogeneous distributed multi-agent information filtering system, called D-SIFTER. D-SIFTER is based on the language-dependent model of Java RMI. The detailed design process and various experiments carried out using D-SIFTER are also described. The results indicate that the distributed inter-agent collaboration improves the overall filtering performance. 相似文献
105.
Though the GroEL and DnaK heat shock proteins are well characterized in prokaryotes, only scanty and controversial information exist about their cellular localization. In the present study, the localization of the heat shock proteins DnaK and GroEL in normal and heat shocked cells of Vibrio cholerae, was investigated both by immunogold labeling of ultrathin sections and biochemical methods. Much of the DnaK was found to be localized at the inner membrane in unstressed cells, most probably at the Bayer's adhesion sites. Data suggested that upon heat shock, the DnaK associated with the membrane continued to remain there, but the newly synthesized DnaK appeared mostly in the cytoplasm. GroEL in both stressed and unstressed cells was found mainly in the cytoplasm. 相似文献
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We developed an ELISA-based method for rapid optimization of various tissue processing parameters in immunogold labeling for electron microscopy. The effects of aldehyde fixation, tannic acid, postfixation, dehydration, temperature, and antigen retrieval on antibody binding activity of Vitreoscilla hemoglobin (VHb) expressed in E. coli cells were assayed by ELISA and the results confirmed by quantitative immunogold labeling transmission electron microscopy (TEM). Our results demonstrated that low concentrations (0.2%) of glutaraldehyde fixation caused minimal loss in total binding compared to higher concentrations. Dehydration in up to 70% ethanol resulted in some distortion of cellular ultrastructure but better antibody binding activity compared to dehydration up to 100%. Postfixation or incorporation of tannic acid in the primary fixative caused almost total loss of activity, whereas antigen retrieval of osmium-postfixed material resulted in approximately 90-100% recovery. The sensitivity of detection of proteins by immunogold labeling electron microscopy depends on the retention of antibody binding activity during tissue processing steps, e.g., fixation and dehydration. Our study indicated that an ELISA-based screening method of various tissue processing procedures could help in rapid selection and optimization of a suitable protocol for immunogold localization and quantification of antigen by TEM. 相似文献
108.
The authors discuss the role of the Environmental Enrichment Committee in developing, implementing, assessing, and modifying a university animal enrichment program. 相似文献
109.
Group housing guinea pigs can save space and money, while improving housing standards. The authors describe enclosure design, enrichments, and husbandry techniques that facilitate group housing female guinea pigs. 相似文献
110.
Quantitation of angiogenesis and its correlation with vascular endothelial growth factor expression in astrocytic tumors 总被引:5,自引:0,他引:5
Gupta K Radotra BD Banerjee AK Nijhawan R 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》2004,26(4):223-229
OBJECTIVE: To quantitate tumor angiogenesis by establishing intratumoral microvessel density (IMD), to study vascular endothelial growth factor (VEGF) expression in different grades of astrocytomas and to correlate VEGF expression with tumor angiogenesis. STUDY DESIGN: Forty cases of astrocytic neoplasms (10 of each grade) were assessed for tumor angiogenesis and VEGF expression. The panendothelial marker CD31 was used to highlight microvessels. Tumor angiogenesis was quantitated as IMD count per square millimeter in areas of high vascularity, or "hot spots," using an image analyzer. VEGF expression was studied in sections of the tumors. IMD counts per square millimeter and VEGF expression were correlated with histologic grade. The angiogenic potential of tumors as reflected by IMD counts per square millimeter was correlated with the intensity of VEGF expression. RESULTS: Vascular proliferation in high grade gliomas was significantly higher as compared to that in low grade gliomas. IMD count per square millimeter revealed a positive correlation with histologic grade in high grade gliomas. Pilocytic astrocytoma and low grade astrocytoma as a group had comparable IMD counts per square millimeter. VEGF expression paralleled IMD counts in rare high grade gliomas only. CONCLUSION: Malignant progression in astrocytoma is heralded and accompanied by increased angiogenesis. VEGF is an important angiogenic factor in high grade gliomas since its expression parallels the increased IMD counts in these tumors. In contrast, in low grade gliomas, angiogenic factors other than VEGF may contribute to vascular proliferation. The results emphasize the role of antiangiogenic therapy as an optimal tool in therapeutic strategies as they become available. 相似文献